Draft California 2020 Integrated Report (303(d) List/305(b) Report)

Supporting Information

Regional Board 5 - Central Valley Region

Water Body Name: Mustang Creek (Merced County)
Water Body ID: CAR5356000020080808193633
Water Body Type: River & Stream
 
DECISION ID
126981
Region 5     
Mustang Creek (Merced County)
 
Pollutant: Indicator Bacteria
Final Listing Decision: Do Not Delist from 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: List on 303(d) list (TMDL required list)(2018)
Revision Status Revised
Sources: A Source Unknown
Expected TMDL Completion Date: 2023
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: The State Water Board’s Water Quality Control Plan for Inland Surface Waters, Enclosed Bays, and Estuaries of California (the “ISWEBE Plan”) contains two bacteria water quality objectives applicable to the REC-1 beneficial use, which were adopted on August 7, 2018. Because the salinity level of this waterbody is equal to or less than 1 part per thousand 95 percent or more of the time, the E. coli bacteria objective applies Therefore, this waterbody is being considered for removal from the CWA section 303(d) List under section 4.3 of the Listing Policy, as applicable, using the E. Coli objective.

In accordance with section 6.1.5.3 of the Listing Policy, data should be representative of the critical timing that the pollutant is expected to impact the waterbody. Indicator bacteria (total coliform, fecal coliform, E. coli, enterococci) populations may fluctuate substantially on a daily, seasonal, or yearly basis. Lacking constant inputs, they do not persist in the environment for a long period and effects are of relatively short duration. As a result, the historic levels of indicator bacteria in the waterbody may be a poor indicator of current risks to human health, particularly when more recent data are available to sufficiently assess the water quality standard. Additionally, water quality conditions in waterbodies may change as a result of management actions that have been implemented to address bacteria. Unrepresentative data may result in incorrectly placing or not placing a water body segment on the list, which could result in the unnecessary expenditure of public resources or missing a human health problem.

Three lines of evidence are available based on the new E. coli objective. There are an insufficient number of samples available to apply the binomial distribution table in section 4.2 of the Listing Policy to determine beneficial use support.

Based on the readily available data and information, the weight of evidence indicates that there is insufficient justification against removing this water segment-pollutant combination from the CWA section 303(d) List.

This conclusion is based on the staff findings that:
1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy.
2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy.
3. There are insufficient samples available to determine listing status using the newly adopted E. coli objective.
4. Pursuant to section 4.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be removed from the section 303(d) list because applicable water quality standards for the pollutant are being exceeded.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.
 
 
Line of Evidence (LOE) for Decision ID 126981, Indicator Bacteria
Region 5     
Mustang Creek (Merced County)
 
LOE ID: 194468
 
Pollutant: Escherichia coli (E. coli)
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Water Contact Recreation
 
Number of Samples: 2
Number of Exceedances: 0
 
Data and Information Type: PATHOGEN MONITORING
Data Used to Assess Water Quality: Water Board staff assessed data for Mustang Creek (Merced County) to determine beneficial use support and the results are as follows: 0 of the 2 samples exceeded the Statistical Threshold Value (STV) water quality threshold for E. coli. The STV is based on a 10% exceedance rate that is calculated monthly.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The bacteria water quality objective applicable to all waters, except Lake Tahoe, where the salinity is less than 10 parts per thousand (ppth) 95 percent or more of the time is a STATISTICAL THRESHOLD VALUE (STV) of 320 cfu/100 mL not to be exceeded more than 10 percent of the time (calculated monthly).
Objective/Criterion Reference: Inland Surface Waters, Enclosed Bays, and Estuaries Plan. Part 1: Trash Provisions; Part 2: Tribal Subsistence Beneficial Uses and Mercury Provisions; Part 3: Bacteria Provisions and Variance Policy
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site(s), station(s): 535XMCAEA
Temporal Representation: The samples were collected between the days of 2013-01-08 and 2013-02-12 .
Environmental Conditions:
QAPP Information: Michael L. Johnson LLC. 2015. Quality Assurance Project Plan for Monitoring by the East San Joaquin Water Quality Coalition.
QAPP Information Reference(s): Quality Assurance Project Plan for Monitoring by the East San Joaquin Water Quality Coalition
 
Line of Evidence (LOE) for Decision ID 126981, Indicator Bacteria
Region 5     
Mustang Creek (Merced County)
 
LOE ID: 68086
 
Pollutant: Escherichia coli (E. coli)
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Water Contact Recreation
 
Number of Samples: 14
Number of Exceedances: 7
 
Data and Information Type: PATHOGEN MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Ag Waiver data for Mustang Creek (Merced County) to determine beneficial use support and results are as follows: 7 of 14 samples exceed the criterion for Escherichia coli.
Data Reference: Data for Various Pollutants in East San Joaquin, 2004-2009.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Waters shall not contain chemical constituents in concentrations that adversely affect beneficial uses. (Water Quality Control Plan, Central Valley Region, Sacramento River and San Joaquin River Basins)
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: The USEPA recommended objective for single sample maximum allowable density of E. coli in freshwater designated beach areas is 235 MPN/100mL.
Guideline Reference: Ambient Water Quality Criteria for Bacteria - 1986. EPA440/5-84-002
 
Spatial Representation: Data for this line of evidence for Mustang Creek (Merced County) was collected at 1 monitoring site [Mustang Creek @ East Ave - 535XMCAEA]
Temporal Representation: Data was collected over the time period 2/12/2007-4/20/2010.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: The Quality Assurance Project Plan by the East San Joaquin Water Quality Coalition, Revision 1.0 was followed.
QAPP Information Reference(s): Quality Assurance Project Plan by the East San Joaquin Water Quality Coalition, Revision 1.0.
 
Line of Evidence (LOE) for Decision ID 126981, Indicator Bacteria
Region 5     
Mustang Creek (Merced County)
 
LOE ID: 23147
 
Pollutant: Escherichia coli (E. coli)
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Water Contact Recreation
 
Number of Samples: 3
Number of Exceedances: 3
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: The East San Joaquin Water Quality Coalition collected 3 samples from May 2006 to August 2006. Three out of 3 samples exceeded the evaluation objective.
Data Reference: Revised Draft of the 2007 Review of the Monitoring Data for the Irrigated Lands Regulatory Conditional Waiver Program
  Monitoring and Reporting Program, Order Nos. R5-2003-0826, R5-2005-0833, and R5-2008-0005 for Coalition Groups Under Resolution No. R5-2003-0105, Conditional Waiver of Waste Discharge Requirements for Discharges From Irrigated Lands Within the Central Valley Region
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that produce detrimental physiological responses in human, plant, animal, or aquatic life. The objective applies regardless of whether the toxicity is caused by a single substance or the interactive effect of multiple substances.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
Objective/Criterion Reference: Ambient Water Quality Criteria for Bacteria - 1986. EPA440/5-84-002
 
Evaluation Guideline: The USEPA E. Coli objective of 235/100 mL in any single sample (USEPA 1986).
Guideline Reference: Ambient Water Quality Criteria for Bacteria - 1986. EPA440/5-84-002
 
Spatial Representation: Samples were collected at Mustang Creek at East Avenue.
Temporal Representation: Sampling occurred from May 2006 to August 2006.
Environmental Conditions:
QAPP Information: Data quality: Good. Monitoring was conducted in accordance with Central Valley Water Board Monitoring and Reporting Program (order number R5-2003-0826) requirements (CVRWQCB, 2003)
QAPP Information Reference(s):
 
 
DECISION ID
118702
Region 5     
Mustang Creek (Merced County)
 
Pollutant: Nitrate/Nitrite (Nitrite + Nitrate as N)
Final Listing Decision: Do Not Delist from 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: List on 303(d) list (TMDL required list)(2018)
Revision Status Revised
Sources: A Source Unknown
Expected TMDL Completion Date: 2027
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: This pollutant is being considered for removal from the CWA section 303(d) List under section 4.1 of the Listing Policy. Under this section a single line of evidence is necessary to assess listing status.

Two lines of evidence are available in the administrative record to assess pollutant. Two of the ten samples exceed the objective for Municipal & Domestic Supply.

Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against removing this water segment-pollutant combination from the CWA section 303(d) List.

This conclusion is based on the staff findings that:
1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy.
2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy.
3. Two of the ten samples exceed the objective for Municipal & Domestic Supply and this exceeds the allowable frequency listed in Table 4.1 of the Listing Policy.
4. Pursuant to section 4.11 of the Listing Policy, no additional data and information are available indicating that standards are met.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be removed from the section 303(d) list because applicable water quality standards for the pollutant are being exceeded.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.
 
 
Line of Evidence (LOE) for Decision ID 118702, Nitrate/Nitrite (Nitrite + Nitrate as N)
Region 5     
Mustang Creek (Merced County)
 
LOE ID: 191960
 
Pollutant: Nitrate/Nitrite (Nitrite + Nitrate as N)
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 2
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed East San Joaquin Water Quality Coalition data for Mustang Creek (Merced County) to determine beneficial use support and results are as follows: 0 of 2 samples exceeded the water quality threshold for Nitrate + Nitrite as N.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The California Maximum Contaminant Level for nitrate + nitrite (as N) incorporated by reference in the Water Quality Control Plan for the Sacramento and San Joaquin River Basins is 10 mg/L (California Code of Regulations, Title 22).
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (535XMCAEA)
Temporal Representation: The samples were collected between the dates of 2013-01-08 and 2013-02-12
Environmental Conditions:
QAPP Information: Michael L. Johnson LLC. 2015. Quality Assurance Project Plan for Monitoring by the East San Joaquin Water Quality Coalition.
QAPP Information Reference(s): Quality Assurance Project Plan for Monitoring by the East San Joaquin Water Quality Coalition
 
Line of Evidence (LOE) for Decision ID 118702, Nitrate/Nitrite (Nitrite + Nitrate as N)
Region 5     
Mustang Creek (Merced County)
 
LOE ID: 67990
 
Pollutant: Nitrate/Nitrite (Nitrite + Nitrate as N)
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 8
Number of Exceedances: 2
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Ag Waiver data for Mustang Creek (Merced County) to determine beneficial use support and results are as follows: 2 of 8 samples exceed the criterion for Nitrate/Nitrite as N.
Data Reference: Data for Various Pollutants in East San Joaquin, 2004-2009.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The California primary maximum contaminant level for nitrate + nitrite (as N) is 10.0 mg/L.
Objective/Criterion Reference: Maximum Contaminant Levels for organic and inorganic chemicals. CCR Title 22
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Data for this line of evidence for Mustang Creek (Merced County) was collected at 1 monitoring site [Mustang Creek @ East Ave - 535XMCAEA]
Temporal Representation: Data was collected over the time period 2/7/2009-4/20/2010.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: The Quality Assurance Project Plan by the East San Joaquin Water Quality Coalition, Revision 1.0 was followed.
QAPP Information Reference(s): Quality Assurance Project Plan by the East San Joaquin Water Quality Coalition, Revision 1.0.
 
 
DECISION ID
122993
Region 5     
Mustang Creek (Merced County)
 
Pollutant: Oxygen, Dissolved
Final Listing Decision: Do Not Delist from 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: List on 303(d) list (TMDL required list)(2018)
Revision Status Revised
Sources: A Source Unknown
Expected TMDL Completion Date: 2027
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: This pollutant is being considered for removal from the CWA section 303(d) List under section 4.2 of the Listing Policy. Under this section a single line of evidence is necessary to assess listing status.

Five lines of evidence are available in the administrative record to assess this pollutant. 19 of the 43 samples exceed the objective for aquatic Life. 7 of the 16 samples exceed the objective for Fish Spawning.

Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against removing this water segment-pollutant combination from the CWA section 303(d) List.

This conclusion is based on the staff findings that:
1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy.
2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy.
3. 19 of the 43 samples exceed the objective for aquatic Life. 7 of the 16 samples exceed the objective for Fish Spawning. These exceed the allowable frequency listed in Table 4.2 of the Listing Policy.
4. Pursuant to section 4.11 of the Listing Policy, no additional data and information are available indicating that standards are met.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be removed from the section 303(d) list because applicable water quality standards for the pollutant are being exceeded.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.
 
 
Line of Evidence (LOE) for Decision ID 122993, Oxygen, Dissolved
Region 5     
Mustang Creek (Merced County)
 
LOE ID: 209164
 
Pollutant: Oxygen, Dissolved
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 16
Number of Exceedances: 7
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed East San Joaquin Water Quality Coalition data for Mustang Creek (Merced County) to determine beneficial use support and results are as follows: 7 of 16 samples exceeded the water quality threshold for Oxygen, Dissolved.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The minimum dissolved oxygen concentration for waters designated as COLD is 7.0 mg/L. (Water Quality Control Plan, Central Valley Region, Sacramento River Basin and San Joaquin Basin)
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (535XMCAEA)
Temporal Representation: The samples were collected between the dates of 2013-01-08 and 2016-12-09
Environmental Conditions:
QAPP Information: Michael L. Johnson LLC. 2015. Quality Assurance Project Plan for Monitoring by the East San Joaquin Water Quality Coalition.
QAPP Information Reference(s): Quality Assurance Project Plan for Monitoring by the East San Joaquin Water Quality Coalition
 
Line of Evidence (LOE) for Decision ID 122993, Oxygen, Dissolved
Region 5     
Mustang Creek (Merced County)
 
LOE ID: 23132
 
Pollutant: Oxygen, Dissolved
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Warm Freshwater Habitat
Aquatic Life Use: Warm Freshwater Habitat
 
Number of Samples: 4
Number of Exceedances: 1
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Four samples were taken from Mustang Creek during 2006. One of the four samples fell below the Water Quality Objective for minimum dissolved oxygen content in surface water.
Data Reference: Revised Draft of the 2007 Review of the Monitoring Data for the Irrigated Lands Regulatory Conditional Waiver Program
  Monitoring and Reporting Program, Order Nos. R5-2003-0826, R5-2005-0833, and R5-2008-0005 for Coalition Groups Under Resolution No. R5-2003-0105, Conditional Waiver of Waste Discharge Requirements for Discharges From Irrigated Lands Within the Central Valley Region
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: From the Sacramento/San Joaquin River Basin Plan the (WARM) Warm Freshwater Habitat criterion is a Minimum Dissolved Oxygen content of 5mg/L.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Samples were collected from Mustang Creek at East Avenue in Merced County.
Temporal Representation: Samples were collected between May and August 2006. Samples were collected at monthly intervals.
Environmental Conditions:
QAPP Information: Data quality: Good. Monitoring was conducted in accordance with Central Valley Water Board Monitoring and Reporting Program (order number R5-2003-0826) requirements (CVRWQCB, 2003)
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 122993, Oxygen, Dissolved
Region 5     
Mustang Creek (Merced County)
 
LOE ID: 208626
 
Pollutant: Oxygen, Dissolved
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Fish Spawning
 
Number of Samples: 16
Number of Exceedances: 7
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed East San Joaquin Water Quality Coalition data for Mustang Creek (Merced County) to determine beneficial use support and results are as follows: 7 of 16 samples exceeded the water quality threshold for Oxygen, Dissolved.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The minimum dissolved oxygen concentration for waters designated as SPWN is 7.0 mg/L. (Water Quality Control Plan, Central Valley Region, Sacramento River Basin and San Joaquin Basin)
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (535XMCAEA)
Temporal Representation: The samples were collected between the dates of 2013-01-08 and 2016-12-09
Environmental Conditions:
QAPP Information: Michael L. Johnson LLC. 2015. Quality Assurance Project Plan for Monitoring by the East San Joaquin Water Quality Coalition.
QAPP Information Reference(s): Quality Assurance Project Plan for Monitoring by the East San Joaquin Water Quality Coalition
 
Line of Evidence (LOE) for Decision ID 122993, Oxygen, Dissolved
Region 5     
Mustang Creek (Merced County)
 
LOE ID: 23146
 
Pollutant: Oxygen, Dissolved
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Warm Freshwater Habitat
Aquatic Life Use: Warm Freshwater Habitat
 
Number of Samples: 5
Number of Exceedances: 1
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Five samples were taken from Mustang Creek between 2002 and 2004. One of the five samples fell below the Water Quality Objective for minimum dissolved oxygen content in surface water.
Data Reference: National Water Quality Assessment database, San Joaquin and Tulare Basins data
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: From the Sacramento/San Joaquin River Basin Plan the (WARM) Warm Freshwater Habitat criterion is a Minimum Dissolved Oxygen content of 5mg/L.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Samples were collected from Mustang Creek 1.1 miles South of Monte Vista Avenue and at the bifurcation structure near Ballico in Merced County.
Temporal Representation: Samples were collected between December 2002 and February 2004. Samples were collected at monthly intervals.
Environmental Conditions:
QAPP Information: Data quality: Good. In accordance with section 6.1.4 of the Listing Policy, data from major monitoring programs in California and Published USGS reports are considered of adequate quality.
QAPP Information Reference(s): National Field Manual for the Collection of Water-Quality Data, Techniques of Water-Resources Investigations, Book 9, Handbooks for Water-Resources Investigations
 
Line of Evidence (LOE) for Decision ID 122993, Oxygen, Dissolved
Region 5     
Mustang Creek (Merced County)
 
LOE ID: 67993
 
Pollutant: Oxygen, Dissolved
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 18
Number of Exceedances: 10
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Ag Waiver data to determine beneficial use support: 10 of 18 sample results exceed the criterion for Oxygen, Dissolved.
Data Reference: Data for Various Pollutants in East San Joaquin, 2004-2009.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The minimum dissolved oxygen concentration for waters designated as COLD is 7.0 mg/L. (Water Quality Control Plan, Central Valley Region, Sacramento River Basin and San Joaquin River Basin)
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Data for this line of evidence was collected at one monitoring site [Mustang Creek @ East Ave-535XMCAEA].
Temporal Representation: Data was collected monthly between 2/12/2007 and 4/20/2010.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: The Quality Assurance Project Plan by the East San Joaquin Water Quality Coalition, Revision 1.0 was followed.
QAPP Information Reference(s): Quality Assurance Project Plan by the East San Joaquin Water Quality Coalition, Revision 1.0.
 
 
DECISION ID
118706
Region 5     
Mustang Creek (Merced County)
 
Pollutant: Total Dissolved Solids
Final Listing Decision: Do Not Delist from 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: List on 303(d) list (TMDL required list)(2018)
Revision Status Revised
Sources: A Source Unknown
Expected TMDL Completion Date: 2027
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: This pollutant is being considered for removal from the CWA section 303(d) List under section 4.2 of the Listing Policy. Under this section a single line of evidence is necessary to assess listing status.

Two lines of evidence are available in the administrative record to assess this pollutant. Five of the 16 samples exceed the objective for Municipal & Domestic Supply.

Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against removing this water segment-pollutant combination from the CWA section 303(d) List.

This conclusion is based on the staff findings that:
1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy.
2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy.
3. Five of the 16 samples exceed the objective for Municipal & Domestic Supply and this exceeds the allowable frequency listed in Table 4.2 of the Listing Policy.
4. Pursuant to section 4.11 of the Listing Policy, no additional data and information are available indicating that standards are met.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be removed from the section 303(d) list because applicable water quality standards for the pollutant are being exceeded.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.
 
 
Line of Evidence (LOE) for Decision ID 118706, Total Dissolved Solids
Region 5     
Mustang Creek (Merced County)
 
LOE ID: 194023
 
Pollutant: Total Dissolved Solids
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 2
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed East San Joaquin Water Quality Coalition data for Mustang Creek (Merced County) to determine beneficial use support and results are as follows: 0 of 2 samples exceeded the water quality threshold for Total Dissolved Solids.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The California Secondary Maximum Contaminant Level for total dissolved solids incorporated by reference in the Water Quality Control Plan for the Sacramento and San Joaquin River Basins is 500 mg/L.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (535XMCAEA)
Temporal Representation: The samples were collected between the dates of 2013-01-08 and 2013-02-12
Environmental Conditions:
QAPP Information: Michael L. Johnson LLC. 2015. Quality Assurance Project Plan for Monitoring by the East San Joaquin Water Quality Coalition.
QAPP Information Reference(s): Quality Assurance Project Plan for Monitoring by the East San Joaquin Water Quality Coalition
 
Line of Evidence (LOE) for Decision ID 118706, Total Dissolved Solids
Region 5     
Mustang Creek (Merced County)
 
LOE ID: 79641
 
Pollutant: Total Dissolved Solids
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 14
Number of Exceedances: 5
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: State Water Board staff assessed ILRP data for Mustang Creek (Merced County) to determine beneficial use support and results are as follows: 5 of 14 samples exceed the criterion for Dissolved Solids.
Data Reference: Data for Various Pollutants in East San Joaquin, 2004-2009.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan, Central Valley Region Sacramento River Basin and San Joaquin River Basin: At a minimum, water designated for MUN shall not contain concentrations of chemical constituents in excess of the MCL specified in Title 22 of the California Code of Regulations. The secondary MCL for Total Dissolved Solids is 500 mg/L.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Data for this line of evidence for Mustang Creek (Merced County) was collected at 1 monitoring site [ Mustang Creek @ East Ave - 535XMCAEA]
Temporal Representation: Data was collected over the time period 2/12/2007-4/20/2010.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: The Quality Assurance Project Plan by the East San Joaquin Water Quality Coalition, Revision 1.0 was followed.
QAPP Information Reference(s):
 
 
DECISION ID
118691
Region 5     
Mustang Creek (Merced County)
 
Pollutant: Chlorpyrifos
Final Listing Decision: Do Not Delist from 303(d) list (being addressed with action other than TMDL)
Last Listing Cycle's Final Listing Decision: Do Not Delist from 303(d) list (being addressed with action other than TMDL)(2018)
Revision Status Revised
Sources: Agriculture
Expected Attainment Date: 2026
Implementation Action Other than TMDL: This water body segment-pollutant combination is being addressed through Basin Plan requirements established under CRWQCB-CVR resolution R5-20140041, and implemented through Board established Waste Discharge Requirements for agricultural discharges. The sources of chlorpyrifos to this segment have been identified as offsite movement of chlorpyrifos from chlorpyrifos applications by the agricultural dischargers regulated by the CRWQCB-CVR WDRs. The Basin Plan identifies numeric water quality objectives for diazinon and chlorpyrifos. The Basin Plan and WDRs require growers to implement management practices through the development and implementation of water quality management plans to meet water quality objectives for chlorpyrifos as soon as possible but no longer than ten years from the date of approval of the Basin Plan Amendment. These management plans are required to be developed and implemented within one year of the Basin Plan Amendment approval. Agricultural management practices to be implemented may include pest management practices, pesticide application practices, vegetation management practices and water management practices, all of which are effective in reducing offsite movement of chlorpyrifos into surface water. The Basin Plan and the Monitoring and Reporting programs in the WDRs require monitoring to determine if adequate reductions are being attained. The Basin Plan and WDRs require management practices to be iteratively improved through updates of the management plans until the water quality objectives are achieved.
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: This pollutant is being considered for removal on the CWA section 303(d) List under sections 2.2 and 4.11 of the Listing Policy. Under 4.11 of the Policy, a minimum of one line of evidence is needed to assess listing status. Four lines of evidence are available in the administrative record to assess this pollutant. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against removing this water segment-pollutant combination from the CWA section 303(d) List. There is sufficient justification to place it in the Being Addressed portion of the CWA section 303(d) List because a the RWQCB has determined that an existing regulatory program is reasonably expected to result in attainment of the standard within a reasonable, specified time frame.
This conclusion is based on the staff findings that:
1. The data used satisfies the data quality requirements of section 6,1,4 of the Policy.
2. The data used satisfies the data quantity requirements of section 6,1,5 of the Policy.
3. Ten of 37 samples exceeded the aquatic life criteria and these exceed the allowable frequency listed in Table 4.1 of the Listing Policy.
4. In 2016, the Board adopted Resolution R5-2014-0041 establishing Basin Plan amendments that primarily address the regulation of agricultural pesticide runoff and discharges of diazinon and chlorpyrifos in the Central Valley which are implemented through Board established Waste Discharge Requirements for agricultural dischargers. The amendments established numeric water quality objectives for chlorpyrifos and a control program to ensure that the objectives will be attained within a reasonable, specified time frame.
The Basin Plan and WDRs require growers to implement management practices through the development and implementation of water quality management plans to meet water quality objectives for chlorpyrifos as soon as possible but no longer than ten years from the date of approval of the Basin Plan Amendment. These management plans are required to be developed and implemented within one year of the Basin Plan Amendment approval.
5. Pursuant to section 4.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be removed from the section 303(d) list because applicable water quality standards for the pollutant are being exceeded.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.
 
 
Line of Evidence (LOE) for Decision ID 118691, Chlorpyrifos
Region 5     
Mustang Creek (Merced County)
 
LOE ID: 187298
 
Pollutant: Chlorpyrifos
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 2
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed East San Joaquin Water Quality Coalition data for Mustang Creek (Merced County) to determine beneficial use support and results are as follows: 0 of 2 samples exceeded the water quality threshold for Chlorpyrifos.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline: The freshwater criterion continuous concentration to protect aquatic organisms is 0.015 ug/L (4 day average)(Siepmann and Finlayson 2000).
Guideline Reference: Water quality criteria for diazinon and chlorpyrifos. Administrative Report 00-3. Rancho Cordova, CA: Pesticide Investigations Unit, Office of Spills and Response. CA Department of Fish and Game (with minor corrections to significant figures as described in Beaulaurier et al., 2005).
 
Spatial Representation: The samples were collected at 1 monitoring site (535XMCAEA)
Temporal Representation: The samples were collected between the dates of 2013-01-08 and 2013-02-12
Environmental Conditions:
QAPP Information: Michael L. Johnson LLC. 2015. Quality Assurance Project Plan for Monitoring by the East San Joaquin Water Quality Coalition.
QAPP Information Reference(s): Quality Assurance Project Plan for Monitoring by the East San Joaquin Water Quality Coalition
 
Line of Evidence (LOE) for Decision ID 118691, Chlorpyrifos
Region 5     
Mustang Creek (Merced County)
 
LOE ID: 23130
 
Pollutant: Chlorpyrifos
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
Aquatic Life Use: Warm Freshwater Habitat
 
Number of Samples: 2
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Three water samples were collected from Mustang Creek from May through August 2006, representing two calculated 4-day average chlorpyrifos concentrations and two 1-hour average chlorpyrifos concentrations. One water sample was not used. Zero of the two calculated 4-day average chlorpyrifos concentrations exceeded the 4-day average chlorpyrifos criterion of 0.015 ug/L. Zero of the two 1-hour average chlorpyrifos concentrations exceeded the 1-hour average chlorpyrifos criterion of 0.025 ug/L. One water sample had only estimated chlorpyrifos concnentrations and, therefore, the sample was not included in this analysis.
Data Reference: Revised Draft of the 2007 Review of the Monitoring Data for the Irrigated Lands Regulatory Conditional Waiver Program
  Monitoring and Reporting Program, Order Nos. R5-2003-0826, R5-2005-0833, and R5-2008-0005 for Coalition Groups Under Resolution No. R5-2003-0105, Conditional Waiver of Waste Discharge Requirements for Discharges From Irrigated Lands Within the Central Valley Region
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses. All waters shall be maintained free of toxic substances in concentrations that produce detrimental physiological responses in human, plant, animal, or aquatic life.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
Objective/Criterion Reference: Water quality criteria for diazinon and chlorpyrifos. Administrative Report 00-3. Rancho Cordova, CA: Pesticide Investigations Unit, Office of Spills and Response. CA Department of Fish and Game
 
Evaluation Guideline: California Department of Fish and Game (CDFG) Hazard Assessment Chlorpyrifos Criteria: 0.015 ug/L as a 4-day average chlorpyrifos concentration, and 0.025 ug/L as a 1-hour average concentration, not to be exceeded more than once every three years.
Guideline Reference: Water quality criteria for diazinon and chlorpyrifos. Administrative Report 00-3. Rancho Cordova, CA: Pesticide Investigations Unit, Office of Spills and Response. CA Department of Fish and Game
 
Spatial Representation: Samples were collected from Mustang Creek at East Avenue.
Temporal Representation: Samples were collected monthly between May, June, and August 2006.
Environmental Conditions:
QAPP Information: Data quality: Good. Monitoring was conducted in accordance with Central Valley Water Board Monitoring and Reporting Program (order number R5-2003-0826) requirements (CVRWQCB, 2003)
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 118691, Chlorpyrifos
Region 5     
Mustang Creek (Merced County)
 
LOE ID: 23131
 
Pollutant: Chlorpyrifos
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
Aquatic Life Use: Warm Freshwater Habitat
 
Number of Samples: 19
Number of Exceedances: 8
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Fifty-four water samples were collected from Mustang Creek from November 2000 to March 2004, representing nineteen calculated 4-day average chlorpyrifos concentrations and fifty-four 1-hour average chlorpyrifos concentrations. Eight of the nineteen calculated 4-day average chlorpyrifos concentrations exceeded the 4-day average chlorpyrifos criterion of 0.015 ug/L. Twenty-five of fifty-four 1-hour average chlorpyrifos concentrations exceeded the 1-hour average chlorpyrifos criterion of 0.025 ug/L.
Data Reference: National Water Quality Assessment database, San Joaquin and Tulare Basins data
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses. All waters shall be maintained free of toxic substances in concentrations that produce detrimental physiological responses in human, plant, animal, or aquatic life.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
Objective/Criterion Reference: Water quality criteria for diazinon and chlorpyrifos. Administrative Report 00-3. Rancho Cordova, CA: Pesticide Investigations Unit, Office of Spills and Response. CA Department of Fish and Game
 
Evaluation Guideline: California Department of Fish and Game Hazard Assessment Chlorpyrifos Criteria: 0.015 ug/L as a 4-day average chlorpyrifos concentration, and 0.025 ug/L as a1-hour average chlorpyrifos concentration, not to be exceeded more than once every three years.
Guideline Reference: Water quality criteria for diazinon and chlorpyrifos. Administrative Report 00-3. Rancho Cordova, CA: Pesticide Investigations Unit, Office of Spills and Response. CA Department of Fish and Game
 
Spatial Representation: Samples were collected in Mustang Creek at the bifurcation structure near Ballico, at Monte Vista near Montpelier, at Newport Road near Ballico, and at Oakdale Road near Montpelier.
Temporal Representation: Samples were collected from November 2000 to March 2004 at variable intervals (hourly, daily, and monthly).
Environmental Conditions:
QAPP Information: Data quality: Good. In accordance with section 6.1.4 of the Listing Policy, data from major monitoring programs in California and Published USGS reports are considered of adequate quality.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 118691, Chlorpyrifos
Region 5     
Mustang Creek (Merced County)
 
LOE ID: 95471
 
Pollutant: Chlorpyrifos
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 14
Number of Exceedances: 2
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Ag Waiver data for Mustang Creek (Merced County) to determine beneficial use support and results are as follows: 2 of 14 samples exceed the chronic exposure criterion for chlorpyrifos.
Data Reference: Data for Various Pollutants in East San Joaquin, 2004-2009.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses. (Water Quality Control Plan, Central Valley Region, Sacramento River Basin and San Joaquin River Basin)
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: The freshwater chronic criterion value for chlorpyrifos is 0.014 ug/L, expressed as a continuous concentration (Siepmann and Finlayson, 2000).
Guideline Reference: Water quality criteria for diazinon and chlorpyrifos. Administrative Report 00-3. Rancho Cordova, CA: Pesticide Investigations Unit, Office of Spills and Response. CA Department of Fish and Game (with minor corrections to significant figures as described in Beaulaurier et al., 2005).
 
Spatial Representation: Data for this line of evidence for Mustang Creek (Merced County) was collected at 1 monitoring site [Mustang Creek @ East Ave - 535XMCAEA]
Temporal Representation: Data was collected over the time period 2/12/2007-4/20/2010.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: The Quality Assurance Project Plan by the East San Joaquin Water Quality Coalition, Revision 1.0 was followed.
QAPP Information Reference(s): Quality Assurance Project Plan by the East San Joaquin Water Quality Coalition, Revision 1.0.
 
 
DECISION ID
118693
Region 5     
Mustang Creek (Merced County)
 
Pollutant: Diazinon
Final Listing Decision: Do Not Delist from 303(d) list (being addressed with action other than TMDL)
Last Listing Cycle's Final Listing Decision: Do Not Delist from 303(d) list (being addressed with action other than TMDL)(2018)
Revision Status Revised
Sources: Agriculture
Expected Attainment Date: 2026
Implementation Action Other than TMDL: This water body segment-pollutant combination is being addressed through Basin Plan requirements established under CRWQCB-CVR resolution R5-20140041, and implemented through Board established Waste Discharge Requirements for agricultural discharges. The sources of diazinon to this segment have been identified as offsite movement of diazinon from diazinon applications by the agricultural dischargers regulated by the CRWQCB-CVR WDRs. The Basin Plan identifies numeric water quality objectives for diazinon and chlorpyrifos. The Basin Plan and WDRs require growers to implement management practices through the development and implementation of water quality management plans to meet water quality objectives for diazinon as soon as possible but no longer than ten years from the date of approval of the Basin Plan Amendment. These management plans are required to be developed and implemented within one year of the Basin Plan Amendment approval. Agricultural management practices to be implemented may include pest management practices, pesticide application practices, vegetation management practices and water management practices, all of which are effective in reducing offsite movement of diazinon into surface water. The Basin Plan and the Monitoring and Reporting programs in the WDRs require monitoring to determine if adequate reductions are being attained. The Basin Plan and WDRs require management practices to be iteratively improved through updates of the management plans until the water quality objectives are achieved.
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: This pollutant is being considered for removal from the CWA section 303(d) List under section 4.1 of the Listing Policy. Under this section a single line of evidence is necessary to assess listing status.

Three lines of evidence are available in the administrative record to assess pollutant- two for the WARM beneficial use and one for the COLD beneficial use. Six of the 70 samples exceed the evaluation guideline for aquatic life.

Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against removing this water segment-pollutant combination from the CWA section 303(d) List.

This conclusion is based on the staff findings that:
1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy.
2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy.
3. Six of the 70 samples exceed the evaluation guideline for aquatic life and this exceeds the allowable frequency listed in Table 4.1 of the Listing Policy.
4. Pursuant to section 4.11 of the Listing Policy, no additional data and information are available indicating that standards are met.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be removed from the section 303(d) list because applicable water quality standards for the pollutant are being exceeded.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.
 
 
Line of Evidence (LOE) for Decision ID 118693, Diazinon
Region 5     
Mustang Creek (Merced County)
 
LOE ID: 23151
 
Pollutant: Diazinon
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
Aquatic Life Use: Warm Freshwater Habitat
 
Number of Samples: 54
Number of Exceedances: 6
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Fifty-four water samples were collected from Mustang Creek from November 2002 through March 2004, representing eighteen calculated 4-day average diazinon concentrations and fifty-four 1-hour average diazinon concentrations. One of the eighteen calculated 4-day average diazinon concentrations exceeded the 4-day average diazinon criterion of 0.100 ug/L. Six of the fifty-four available 1-hour average diazinon concentrations exceeded the 1-hour average diazinon criterion of 0.160 ug/L.
Data Reference: National Water Quality Assessment database, San Joaquin and Tulare Basins data
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses. All waters shall be maintained free of toxic substances in concentrations that produce detrimental physiological responses in human, plant, animal, or aquatic life.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
Objective/Criterion Reference: Water quality criteria for diazinon and chlorpyrifos. Administrative Report 00-3. Rancho Cordova, CA: Pesticide Investigations Unit, Office of Spills and Response. CA Department of Fish and Game
 
Evaluation Guideline: California Department of Fish and Game Hazard Assessment diazinon Criteria: 0.160 ug/L as a 1-hour average concentration, and 0.100 ug/L as a 4-day average concentration, not to be exceeded more than once every three years.
Guideline Reference: Water quality criteria for diazinon and chlorpyrifos. Administrative Report 00-3. Rancho Cordova, CA: Pesticide Investigations Unit, Office of Spills and Response. CA Department of Fish and Game
 
Spatial Representation: Samples were collected from Mustang Creek at: 1.1 miles south of Monte Vista Avenue near Montpelier; at Bifurcation Structure near Ballico; at Monte Vista Avenue near Montpelier; at Newport Road near Ballico; and Below Reservoir near Oakdale Road near Montpelier.
Temporal Representation: Samples were collected in November and December 2002, July and December 2003, February and March 2004.
Environmental Conditions:
QAPP Information: Data quality: Good. In accordance with section 6.1.4 of the Listing Policy, data from major monitoring programs in California and Published USGS reports are considered of adequate quality.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 118693, Diazinon
Region 5     
Mustang Creek (Merced County)
 
LOE ID: 68068
 
Pollutant: Diazinon
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 14
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Ag Waiver data for Mustang Creek (Merced County) to determine beneficial use support and results are as follows: 0 of 14 samples exceed the criterion for Diazinon.
Data Reference: Data for Various Pollutants in East San Joaquin, 2004-2009.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses. (Water Quality Control Plan, Central Valley Region, Sacramento River Basin and San Joaquin River Basin)
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: The freshwater chronic criterion value for diazinon is 0.1 ug/L, expressed as a continuous concentration (Finlayson, 2004).
Guideline Reference: Water quality for diazinon. Memorandum to J. Karkoski, Central Valley RWQCB. Rancho Cordova, CA: Pesticide Investigation Unit, CA Department of Fish and Game
 
Spatial Representation: Data for this line of evidence for Mustang Creek (Merced County) was collected at 1 monitoring site [Mustang Creek @ East Ave - 535XMCAEA]
Temporal Representation: Data was collected over the time period 2/12/2007-4/20/2010.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: The Quality Assurance Project Plan by the East San Joaquin Water Quality Coalition, Revision 1.0 was followed.
QAPP Information Reference(s): Quality Assurance Project Plan by the East San Joaquin Water Quality Coalition, Revision 1.0.
 
Line of Evidence (LOE) for Decision ID 118693, Diazinon
Region 5     
Mustang Creek (Merced County)
 
LOE ID: 188625
 
Pollutant: Diazinon
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 2
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed East San Joaquin Water Quality Coalition data for Mustang Creek (Merced County) to determine beneficial use support and results are as follows: 0 of 2 samples exceeded the water quality threshold for Diazinon.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline: The freshwater chronic value for diazinon is 0.1 ug/L (4 day average)(Finlayson, 2004).
Guideline Reference: Water quality criteria for diazinon and chlorpyrifos. Administrative Report 00-3. Rancho Cordova, CA: Pesticide Investigations Unit, Office of Spills and Response. CA Department of Fish and Game (with minor corrections to significant figures as described in Beaulaurier et al., 2005).
 
Spatial Representation: The samples were collected at 1 monitoring site (535XMCAEA)
Temporal Representation: The samples were collected between the dates of 2013-01-08 and 2013-02-12
Environmental Conditions:
QAPP Information: Michael L. Johnson LLC. 2015. Quality Assurance Project Plan for Monitoring by the East San Joaquin Water Quality Coalition.
QAPP Information Reference(s): Quality Assurance Project Plan for Monitoring by the East San Joaquin Water Quality Coalition
 
 
DECISION ID
118705
Region 5     
Mustang Creek (Merced County)
 
Pollutant: Simazine
Final Listing Decision: Do Not Delist from 303(d) list (being addressed with action other than TMDL)
Last Listing Cycle's Final Listing Decision: Do Not Delist from 303(d) list (being addressed with action other than TMDL)(2018)
Revision Status Revised
Sources: Agriculture
Expected Attainment Date: 2018
Implementation Action Other than TMDL: This listing is being addressed through the implementation of the Central Valley Regional Water Quality Control Board Irrigated Lands Regulatory program (ILRP) Waste Discharge Requirements (WDRs) for Growers within the Eastern San Joaquin River Watershed that are Members of the Third-Party Group (Order R5-2012-0016) and in Waste Discharge Requirements General Order for Discharges from Irrigated Lands within the Central Valley Region for Dischargers not Participating in a Third-party Group (Order R5-2013-0100). The sources of simazine to this waterbody segment have been identified as offsite movement of simazine from simazine applications by the agricultural dischargers regulated by the CRWQCB-CVR WDRs. The WDRs include a time schedule, milestones and a monitoring and reporting program. The WDRs require growers to develop and implement water quality management plans iteratively to attain water quality objectives as soon as possible, but no later than ten years from the identification of water quality exceedances. The WDRs monitoring and reporting program requires growers to regularly monitor water bodies with management plans to assess progress at meeting standards and regularly report monitoring results to the Regional Board. A management plan for simazine in Mustang Creek was developed in 2008 and is being implemented and monitoring is ongoing.
Agricultural management practices being used to reduce offsite movement of simazine into surface water include alternative weed management practices, pesticide application practices, vegetation management and water management practices, pesticide application practices, vegetation management and water management practices, all of which are effective in reducing offsite movement of simazine into surface water. The WDRs require management practices to be iteratively improved through updates of the management plans until water quality criteria are achieved. The simazine criteria are expected to be attained through continued implementation and improvement of management practices within the required 10-year compliance time frame.
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: This water body and pollutant combination is being reconsidered, during the 2014 Integrated Report cycle, for removal from the 303(d) list under section 2.2 of the Listing Policy. The evidence indicated that simazine concentrations are not attaining water quality standards.

This water body and pollutant combination was considered for removal from the 303(d) list under sections 2.2 and 4.11 of the Listing Policy. Under section 4.11, a single line of evidence is necessary to assess listing status.

Six lines of evidence are available to assess this waterbody-pollutant combination for Municipal and Domestic Supply (MUN) and Cold Freshwater Habitat (COLD). Thirty-six of the 79 samples, reported as a total concentration or with the fraction not reported, exceed the objective for MUN. One of the 19 samples, reported as a total concentration, exceed the guideline for COLD.

LOE 68011 has been replaced by LOE 222426 due to a reassessment of data using a U.S. EPA aquatic life benchmark.

Based on the readily available data and information, the weight of evidence indicates this water segment-pollutant combination is being addressed by an enforceable regulatory program, other than a TMDL, that is reasonably expected to result in attainment of the water quality standards within a reasonable, specified time frame.
This conclusion is based on the staff findings that:
1. The data used satisfy the data quality requirements of section 6.1.4 of the Policy.
2. The data used satisfy the data quantity requirements of section 6.1.5 of the Policy.
3. Thirty-six of the 79 samples, reported as a total concentration or with the fraction not reported, exceed the objective for MUN. One of the 19 samples, reported as a total concentration, exceed the guideline for COLD. This exceeds the allowable frequency listed in Table 4.1 of the Listing Policy.
4. This listing is being addressed through the implementation of the Central Valley Regional Water Quality Control Board Irrigated Lands Regulatory program (ILRP) Waste Discharge Requirements (WDRs) for Growers within the Eastern San Joaquin River Watershed that are Members of the Third-Party Group (Order R5-2012-0016) and in WDRs General Order for Discharges from Irrigated Lands within the Central Valley Region for Dischargers not Participating in a Third-party Group (Order R5-2013-0100).
The WDRs include a time schedule, milestones and a monitoring and reporting program. The WDRs require growers to develop and implement water quality management plans iteratively to attain water quality objectives as soon as possible, but no later than ten years from the identification of water quality exceedances. A management plan for simazine in Mustang Creek was developed in 2008 and is being implemented and monitoring is ongoing. Agricultural management practices being used to reduce offsite movement of simazine into surface water include alternative weed management practices, pesticide application practices, vegetation management and water management practices, pesticide application practices, vegetation management and water management practices, all of which are effective in reducing offsite movement of simazine into surface water. The simazine criteria are expected to be attained through continued implementation and improvement of management practices within the required 10-year compliance time frame.
5. Pursuant to section 4.11 of the Listing Policy, no additional data and information are available indicating that standards are being met.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be removed from the section 303(d) list because applicable water quality standards for the pollutant are being exceeded.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.
 
 
Line of Evidence (LOE) for Decision ID 118705, Simazine
Region 5     
Mustang Creek (Merced County)
 
LOE ID: 95601
 
Pollutant: Simazine
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 8
Number of Exceedances: 3
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: 52 water samples were collected from Mustang Creek from November 2002 to March 2004 that were averaged using a 7-day average per the evaluation guideline resulting in 8 averaged concentrations. Three out of 8 averaged concentrations exceeded the maximum concentration of 4 ug/L.
Data Reference: Correspondence between the Department of Pesticide Regulation and Central Valley Regional Water Quality Control Board regarding water quality data for waterbodies in the Central Valley
  Surface Water database (SWDB) for Central Valley waterbodies, 2000-2005
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: At a minimum, water designated for use as domestic or municipal supply (MUN) shall not contain concentrations of chemical constituents in excess of the maximum contaminant levels (MCLs) specified in the following provisions of Title 22 of the California Code of Regulations, which are incorporated by reference into this plan: Tables 64431-A (Inorganic Chemicals) and 64431-B (Fluoride) of Section 64431, Table 64444-A (Organic Chemicals) of Section 64444, and Tables 64449-A (Secondary Maximum Contaminant Levels-Consumer Acceptance Limits) and 64449-B (Secondary Maximum Contaminant Levels-Ranges) of Section 64449. The Maximum Contaminant Level (MCL) for simazine is 4 ug/L.
Objective/Criterion Reference: California Code of Regulations, Title 22, Division 4, Chapter 15. Domestic Water Quality and Monitoring
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Samples were collected from Mustang Creek at four different sites: Bifurcation Structure near Ballico, Monte Vista, Newport Road near Ballico, and Oakdale Road.
Temporal Representation: Samples were collected at variable intervals (e.g. several samples per day, daily, and weekly) from November 2002 through March 2004.
Environmental Conditions:
QAPP Information: Data quality: Good. Minimum requirements for the CDPR Surface Water Database are: Name of the sampling agency or organization, Date that each sample was collected, Date of each sample analysis, County where samples were taken, Detailed sampling location information (including latitude and longitude or township/range/section if available), detailed map or description of each sampling site (i.e., address, cross roads, etc.), Name or description of water body sampled, Name of the active ingredient analyzed for; concentration detected (with unit of measurement), and limit of quantitation, Description of analytical QA/QC plan, or statement that no formal plan exists. Additional optional requirements are included on DPR's webpage at http://www.cdpr.ca.gov/docs/emon/surfwtr/caps/req.htm
QAPP Information Reference(s): Standard Operating Procedure for Conducting Surface Water Monitoring for Pesticides
 
Line of Evidence (LOE) for Decision ID 118705, Simazine
Region 5     
Mustang Creek (Merced County)
 
LOE ID: 68012
 
Pollutant: Simazine
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 17
Number of Exceedances: 2
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Ag Waiver data for Mustang Creek (Merced County) to determine beneficial use support and results are as follows: 2 of 17 samples exceed the criterion for Simazine.
Data Reference: Data for Various Pollutants in East San Joaquin, 2004-2009.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The California primary maximum contaminant level for Simazine is 4 ug/L.
Objective/Criterion Reference: Maximum Contaminant Levels for organic and inorganic chemicals. CCR Title 22
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Data for this line of evidence for Mustang Creek (Merced County) was collected at 1 monitoring site [Mustang Creek @ East Ave - 535XMCAEA]
Temporal Representation: Data was collected over the time period 5/18/2006-4/20/2010.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: The Quality Assurance Project Plan by the East San Joaquin Water Quality Coalition, Revision 1.0 was followed.
QAPP Information Reference(s): Quality Assurance Project Plan by the East San Joaquin Water Quality Coalition, Revision 1.0.
 
Line of Evidence (LOE) for Decision ID 118705, Simazine
Region 5     
Mustang Creek (Merced County)
 
LOE ID: 23128
 
Pollutant: Simazine
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 52
Number of Exceedances: 31
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: 52 water samples were collected from Mustang Creek from November 2002 through February 2004, representing 52 concentrations.31 of 52 concentrations exceeded the MCL for drinking water standard (4 ug/L);
Data Reference: Surface Water database (SWDB) for Central Valley waterbodies, 2000-2005
  Correspondence between the Department of Pesticide Regulation and Central Valley Regional Water Quality Control Board regarding water quality data for waterbodies in the Central Valley
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: At a minimum, water designated for use as domestic or municipal supply (MUN) shall not contain concentrations of chemical constituents in excess of the maximum contaminant levels (MCLs) specified in the following provisions of Title 22 of the California Code of Regulations, which are incorporated by reference into this plan: Tables 64431-A (Inorganic Chemicals) and 64431-B (Fluoride) of Section 64431, Table 64444-A (Organic Chemicals) of Section 64444, and Tables 64449-A (Secondary Maximum Contaminant Levels-Consumer Acceptance Limits) and 64449-B (Secondary Maximum Contaminant Levels-Ranges) of Section 64449.

The Maximum Contaminant Level (MCL) for simazine is 4 ug/L.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
Objective/Criterion Reference: California Code of Regulations, Title 22, Division 4, Chapter 15. Domestic Water Quality and Monitoring
 
Evaluation Guideline:
Guideline Reference: California Code of Regulations, Title 22, Division 4, Chapter 15. Domestic Water Quality and Monitoring
 
Spatial Representation: Samples were collected from Mustang Creek at four different sites: Bifurcation Structure near Ballico, Monte Vista, Newport Road near Ballico, and Oakdale Road.
Temporal Representation: Samples were collected at variable intervals (e.g. several samples per day, daily, and weekly) from November 2002 through February 2004.
Environmental Conditions:
QAPP Information: Data quality: Good. Minimum requirements for the CDPR Surface Water Database are: Name of the sampling agency or organization, Date that each sample was collected, Date of each sample analysis, County where samples were taken, Detailed sampling location information (including latitude and longitude or township/range/section if available), detailed map or description of each sampling site (i.e., address, cross roads, etc.), Name or description of water body sampled, Name of the active ingredient analyzed for; concentration detected (with unit of measurement), and limit of quantitation, Description of analytical QA/QC plan, or statement that no formal plan exists. Additional optional requirements are included on DPR's webpage at http://www.cdpr.ca.gov/docs/emon/surfwtr/caps/req.htm
QAPP Information Reference(s): Standard Operating Procedure for Conducting Surface Water Monitoring for Pesticides
 
Line of Evidence (LOE) for Decision ID 118705, Simazine
Region 5     
Mustang Creek (Merced County)
 
LOE ID: 193687
 
Pollutant: Simazine
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 2
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed East San Joaquin Water Quality Coalition data for Mustang Creek (Merced County) to determine beneficial use support and results are as follows: 0 of 2 samples exceeded the water quality threshold for Simazine.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Water Quality Control Plan for the Sacramento and San Joaquin River Basins).
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline: The evaluation guideline for Simazine is the USEPA Aquatic Life Benchmark of 6 ug/L for a nonvascular plant (acute).
Guideline Reference: OPP Aquatic Life Benchmarks
 
Spatial Representation: The samples were collected at 1 monitoring site (535XMCAEA)
Temporal Representation: The samples were collected between the dates of 2013-01-08 and 2013-02-12
Environmental Conditions:
QAPP Information: Michael L. Johnson LLC. 2015. Quality Assurance Project Plan for Monitoring by the East San Joaquin Water Quality Coalition.
QAPP Information Reference(s): Quality Assurance Project Plan for Monitoring by the East San Joaquin Water Quality Coalition
 
Line of Evidence (LOE) for Decision ID 118705, Simazine
Region 5     
Mustang Creek (Merced County)
 
LOE ID: 222426
 
Pollutant: Simazine
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 17
Number of Exceedances: 1
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed ILRP_ESJWQC data for Mustang Creek (Merced County) to determine beneficial use support and results are as follows: 1 of 17 samples exceeded the water quality threshold for Simazine.
Data Reference: Data for Various Pollutants in East San Joaquin, 2004-2009.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Water Quality Control Plan for the Sacramento and San Joaquin River Basins).
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline: The evaluation guideline for Simazine is the USEPA Aquatic Life Benchmark of 6 ug/L for a nonvascular plant (acute).
Guideline Reference: OPP Aquatic Life Benchmarks
 
Spatial Representation: The samples were collected at 1 monitoring site (535XMCAEA)
Temporal Representation: The samples were collected between the dates of 2006-05-18 and 2010-04-20
Environmental Conditions:
QAPP Information: The Quality Assurance Project Plan by the East San Joaquin Water Quality Coalition, Revision 1.0 was followed.
QAPP Information Reference(s): Quality Assurance Project Plan by the East San Joaquin Water Quality Coalition, Revision 1.0.
 
Line of Evidence (LOE) for Decision ID 118705, Simazine
Region 5     
Mustang Creek (Merced County)
 
LOE ID: 193759
 
Pollutant: Simazine
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 2
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed East San Joaquin Water Quality Coalition data for Mustang Creek (Merced County) to determine beneficial use support and results are as follows: 0 of 2 samples exceeded the water quality threshold for Simazine.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The California Primary Maximum Contaminant Level for Simazine incorporated by reference in the Water Quality Control Plan for the Sacramento and San Joaquin River Basins is 0.004 mg/L.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (535XMCAEA)
Temporal Representation: The samples were collected between the dates of 2013-01-08 and 2013-02-12
Environmental Conditions:
QAPP Information: Michael L. Johnson LLC. 2015. Quality Assurance Project Plan for Monitoring by the East San Joaquin Water Quality Coalition.
QAPP Information Reference(s): Quality Assurance Project Plan for Monitoring by the East San Joaquin Water Quality Coalition
 
 
DECISION ID
73737
Region 5     
Mustang Creek (Merced County)
 
Pollutant: cis-permethrin
Final Listing Decision: Do Not Delist from 303(d) list (being addressed with action other than TMDL)
Last Listing Cycle's Final Listing Decision: List on 303(d) list (TMDL required list)(2016)
Revision Status Revised
Sources: A Source Unknown
Expected Attainment Date: 2037
Implementation Action Other than TMDL: Resolution R5-2017-0057, a Basin Plan Amendment for Pyrethroid Discharges, established a conditional prohibition of pyrethroids discharges. The Amendment requires agricultural dischargers of pyrethroids with known pyrethroid impairments develop and implement management plans through the Irrigated Lands Regulatory Program to reduce pyrethroid pesticides discharges. Mustang Creek (Merced County) was identified in the resolution and should obtain the narrative water quality objective for toxicity as soon as practicable, but no later than 20 years from the resolution date.
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: This pollutant is being considered for removal on the CWA section 303(d) List under sections 2.2 and of the Listing Policy. Under 4.11 of the Policy, a minimum of one line of evidence is needed to assess listing status. One line of evidence is available in the administrative record to assess this pollutant. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against removing this water segment-pollutant combination from the CWA section 303(d) List. There is sufficient justification to place it in the Being Addressed portion of the CWA section 303(d) List because a the RWQCB has determined that an existing regulatory program is reasonably expected to result in attainment of the standard within a reasonable, specified time frame.
This conclusion is based on the staff findings that:
1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy.
2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy.
3. Nine of nine samples exceeded the evaluation guideline for WARM and these exceed the allowable frequency listed in Table 4.1 of the Listing Policy.
4. This listing is being addressed through the implementation of the Central Valley Regional Water Quality Control Board, Irrigated Lands Regulatory Program (ILRP) General Orders that have been approved by the RWQCB. The ILRP will implement management plans to address the pollutant and is expected to attain applicable water quality standards before or by 2037.
5. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be removed from the section 303(d) list because applicable water quality standards for the pollutant are being exceeded.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation:
 
 
Line of Evidence (LOE) for Decision ID 73737, cis-permethrin
Region 5     
Mustang Creek (Merced County)
 
LOE ID: 21753
 
Pollutant: cis-permethrin
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 9
Number of Exceedances: 9
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Fifty-four water samples (including many replicate samples) were collected from five locations on Mustang Creek, between November 2002 and March 2004.
Thirty-eight of the 54 samples had concentrations less than quantitation limits and quantitation limits (0.0060 ug/L) greater than the Evaluation Guideline value. Therefore, the results for these samples were not used in this analysis in accordance with section 6.1.5.5 of the Listing Policy.
The sixteen remaining usable water samples were collected at either at the bifurcation structure near Ballico (8 samples) or at Monte Vista Avenue near Montpelier (8 samples). Due to replicate (duplicate and triplicate) analyses, the 16 water samples represent a total of only 9 date-averaged water sample concentrations for both locations. Nine of the 9 averaged water concentrations exceeded the Evaluation Guideline value of 0.0033 ug/L.
Data Reference: National Water Quality Assessment database, San Joaquin and Tulare Basins data
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses. All waters shall be maintained free of toxic substances in concentrations that produce detrimental physiological responses in human, plant, animal, or aquatic life.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: Where valid testing has developed 96 hour LC50 values for aquatic organisms (the concentration that kills one half of the test organisms in 96 hours), the Board will consider one tenth of this value for the most sensitive species tested as the upper limit (daily maximum) for the protection of aquatic life. Other available technical information on the pesticide (such as Lowest Observed Effect Concentrations and No Observed Effect Levels), the water bodies and the organisms involved will be evaluated to determine if lower concentrations are required to meet the narrative objectives. The 24-hour LC50 for cis-permethrin, for the most sensitive species (Tanytarsus sp., a midge) is 0.033 ug/L. Therefore, the one-tenth LC50 value for the cis-permethrin Evaluation Guideline is 0.0033 ug/L.
Guideline Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Spatial Representation: Water samples were collected from Mustang Creek at five locations: at the bifurcation structure near Ballico (19 samples); at Monte Vista Avenue near Montpelier (23 samples); at Newport Road near Ballico (7 samples); below reservoir near Oakdale Road near Montpelier (4 samples); and at 1.1 mile south of Monte Vista Avenue near Montpelier (1 sample).
Temporal Representation: The sixteen water samples with usable data were collected from Mustang Creek at the bifurcation structure near Ballico on 4, 18, 19, 25, and 26 February 2004, and at Monte Vista Avenue near Montpelier on 2, 3, 18, and 25 February 2004.
Environmental Conditions:
QAPP Information: Data quality: Good. In accordance with section 6.1.4 of the Listing Policy, data from major monitoring programs in California and Published USGS reports are considered of adequate quality.
QAPP Information Reference(s):
 
 
DECISION ID
118716
Region 5     
Mustang Creek (Merced County)
 
Pollutant: Aldicarb
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: Do Not List on 303(d) list (TMDL required list)(2018)
Revision Status Revised
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: This pollutant is being considered for placement on the CWA section 303(d) List under section 3.1 of the Listing Policy.

Zero samples exceeded the objectives, guidelines, or criteria for beneficial uses applicable to this water segment-pollutant combination, which is less than the minimum number of exceedances needed to place the water segment on the section CWA section 303(d) List for toxicants (Table 3.1 of the Listing Policy).

LOE 68028 has been replaced by LOE 221428 due to a reassessment of data using a U.S. EPA aquatic life benchmark.

The data used satisfies the data quality requirements (section 6.1.4) and data quantity requirements (section 6.1.5) of the Listing Policy.

Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the CWA section 303(d) List.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because applicable water quality standards are not being exceeded.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.
 
 
Line of Evidence (LOE) for Decision ID 118716, Aldicarb
Region 5     
Mustang Creek (Merced County)
 
LOE ID: 185934
 
Pollutant: Aldicarb
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 2
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed East San Joaquin Water Quality Coalition data for Mustang Creek (Merced County) to determine beneficial use support and results are as follows: 0 of 2 samples exceeded the water quality threshold for Aldicarb.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The California Maximum Contaminant Level for aldicarb incorporated by reference in the Water Quality Control Plan for the Sacramento and San Joaquin River Basins is 3 ug/L
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (535XMCAEA)
Temporal Representation: The samples were collected between the dates of 2013-01-08 and 2013-02-12
Environmental Conditions:
QAPP Information: Michael L. Johnson LLC. 2015. Quality Assurance Project Plan for Monitoring by the East San Joaquin Water Quality Coalition.
QAPP Information Reference(s): Quality Assurance Project Plan for Monitoring by the East San Joaquin Water Quality Coalition
 
Line of Evidence (LOE) for Decision ID 118716, Aldicarb
Region 5     
Mustang Creek (Merced County)
 
LOE ID: 185882
 
Pollutant: Aldicarb
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 2
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed East San Joaquin Water Quality Coalition data for Mustang Creek (Merced County) to determine beneficial use support and results are as follows: 0 of 2 samples exceeded the water quality threshold for Aldicarb.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Water Quality Control Plan for the Sacramento and San Joaquin River Basins).
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline: The evaluation guideline for Aldicarb is the USEPA Aquatic Life Benchmark of 0.46 ug/L for a fish (chronic).
Guideline Reference: OPP Aquatic Life Benchmarks
 
Spatial Representation: The samples were collected at 1 monitoring site (535XMCAEA)
Temporal Representation: The samples were collected between the dates of 2013-01-08 and 2013-02-12
Environmental Conditions:
QAPP Information: Michael L. Johnson LLC. 2015. Quality Assurance Project Plan for Monitoring by the East San Joaquin Water Quality Coalition.
QAPP Information Reference(s): Quality Assurance Project Plan for Monitoring by the East San Joaquin Water Quality Coalition
 
Line of Evidence (LOE) for Decision ID 118716, Aldicarb
Region 5     
Mustang Creek (Merced County)
 
LOE ID: 221428
 
Pollutant: Aldicarb
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 17
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed ILRP_ESJWQC data for Mustang Creek (Merced County) to determine beneficial use support and results are as follows: 0 of 17 samples exceeded the water quality threshold for Aldicarb.
Data Reference: Data for Various Pollutants in East San Joaquin, 2004-2009.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Water Quality Control Plan for the Sacramento and San Joaquin River Basins).
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline: The evaluation guideline for Aldicarb is the USEPA Aquatic Life Benchmark of 0.46 ug/L for a fish (chronic).
Guideline Reference: OPP Aquatic Life Benchmarks
 
Spatial Representation: The samples were collected at 1 monitoring site (535XMCAEA)
Temporal Representation: The samples were collected between the dates of 2006-05-18 and 2010-04-20
Environmental Conditions:
QAPP Information: The Quality Assurance Project Plan by the East San Joaquin Water Quality Coalition, Revision 1.0 was followed.
QAPP Information Reference(s): Quality Assurance Project Plan by the East San Joaquin Water Quality Coalition, Revision 1.0.
 
 
DECISION ID
118687
Region 5     
Mustang Creek (Merced County)
 
Pollutant: Atrazine
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: Do Not List on 303(d) list (TMDL required list)(2018)
Revision Status Revised
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: This pollutant is being considered for placement on the CWA section 303(d) List under section 3.1 of the Listing Policy.

Zero samples exceeded the objectives, guidelines, or criteria for beneficial uses applicable to this water segment-pollutant combination, which is less than the minimum number of exceedances needed to place the water segment on the section CWA section 303(d) List for toxicants (Table 3.1 of the Listing Policy).

LOE 68037 has been replaced by LOE 221676 due to a reassessment of data using a U.S. EPA aquatic life benchmark.

The data used satisfies the data quality requirements (section 6.1.4) and data quantity requirements (section 6.1.5) of the Listing Policy.

Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the CWA section 303(d) List.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because applicable water quality standards are not being exceeded.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.
 
 
Line of Evidence (LOE) for Decision ID 118687, Atrazine
Region 5     
Mustang Creek (Merced County)
 
LOE ID: 186244
 
Pollutant: Atrazine
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 2
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed East San Joaquin Water Quality Coalition data for Mustang Creek (Merced County) to determine beneficial use support and results are as follows: 0 of 2 samples exceeded the water quality threshold for Atrazine.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Water Quality Control Plan for the Sacramento and San Joaquin River Basins).
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline: The evaluation guideline for Atrazine is the USEPA Aquatic Life Benchmark of <1 ug/L for a nonvascular plant (acute).
Guideline Reference: OPP Aquatic Life Benchmarks
 
Spatial Representation: The samples were collected at 1 monitoring site (535XMCAEA)
Temporal Representation: The samples were collected between the dates of 2013-01-08 and 2013-02-12
Environmental Conditions:
QAPP Information: Michael L. Johnson LLC. 2015. Quality Assurance Project Plan for Monitoring by the East San Joaquin Water Quality Coalition.
QAPP Information Reference(s): Quality Assurance Project Plan for Monitoring by the East San Joaquin Water Quality Coalition
 
Line of Evidence (LOE) for Decision ID 118687, Atrazine
Region 5     
Mustang Creek (Merced County)
 
LOE ID: 221676
 
Pollutant: Atrazine
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 17
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed ILRP_ESJWQC data for Mustang Creek (Merced County) to determine beneficial use support and results are as follows: 0 of 17 samples exceeded the water quality threshold for Atrazine.
Data Reference: Data for Various Pollutants in East San Joaquin, 2004-2009.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Water Quality Control Plan for the Sacramento and San Joaquin River Basins).
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline: The evaluation guideline for Atrazine is the USEPA Aquatic Life Benchmark of <1 ug/L for a nonvascular plant (acute).
Guideline Reference: OPP Aquatic Life Benchmarks
 
Spatial Representation: The samples were collected at 1 monitoring site (535XMCAEA)
Temporal Representation: The samples were collected between the dates of 2006-05-18 and 2010-04-20
Environmental Conditions:
QAPP Information: The Quality Assurance Project Plan by the East San Joaquin Water Quality Coalition, Revision 1.0 was followed.
QAPP Information Reference(s): Quality Assurance Project Plan by the East San Joaquin Water Quality Coalition, Revision 1.0.
 
Line of Evidence (LOE) for Decision ID 118687, Atrazine
Region 5     
Mustang Creek (Merced County)
 
LOE ID: 186397
 
Pollutant: Atrazine
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 2
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed East San Joaquin Water Quality Coalition data for Mustang Creek (Merced County) to determine beneficial use support and results are as follows: 0 of 2 samples exceeded the water quality threshold for Atrazine.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The California Primary Maximum Contaminant Level for atrazine incorporated by reference in the Water Quality Control Plan for the Sacramento and San Joaquin River Basins is 0.001 mg/L.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (535XMCAEA)
Temporal Representation: The samples were collected between the dates of 2013-01-08 and 2013-02-12
Environmental Conditions:
QAPP Information: Michael L. Johnson LLC. 2015. Quality Assurance Project Plan for Monitoring by the East San Joaquin Water Quality Coalition.
QAPP Information Reference(s): Quality Assurance Project Plan for Monitoring by the East San Joaquin Water Quality Coalition
 
Line of Evidence (LOE) for Decision ID 118687, Atrazine
Region 5     
Mustang Creek (Merced County)
 
LOE ID: 68036
 
Pollutant: Atrazine
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 14
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Ag Waiver data for Mustang Creek (Merced County) to determine beneficial use support and results are as follows: 0 of 14 samples exceed the criterion for Atrazine.
Data Reference: Data for Various Pollutants in East San Joaquin, 2004-2009.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The California primary maximum contaminant level for atrazine is 1 ug/L.
Objective/Criterion Reference: Maximum Contaminant Levels for organic and inorganic chemicals. CCR Title 22
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Data for this line of evidence for Mustang Creek (Merced County) was collected at 1 monitoring site [Mustang Creek @ East Ave - 535XMCAEA]
Temporal Representation: Data was collected over the time period 2/12/2007-4/20/2010.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: The Quality Assurance Project Plan by the East San Joaquin Water Quality Coalition, Revision 1.0 was followed.
QAPP Information Reference(s): Quality Assurance Project Plan by the East San Joaquin Water Quality Coalition, Revision 1.0.
 
 
DECISION ID
118697
Region 5     
Mustang Creek (Merced County)
 
Pollutant: Azinphos-methyl (Guthion)
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: Do Not List on 303(d) list (TMDL required list)(2018)
Revision Status Revised
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: This pollutant is being considered for placement on the CWA section 303(d) List under section 3.1 of the Listing Policy. Under section 3.1 a one line(s) of evidence are necessary to assess listing status.

One line of evidence is available in the administrative record to assess this pollutant. Zero of the zero samples exceed the Evaluation Guideline.

Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the CWA section 303(d) List.

This conclusion is based on the staff findings that:
1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy.
2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy.
3. Zero of zero samples exceeded Evaluation Guideline and this sample size is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating. A minimum of 16 samples is needed to determine if a beneficial use is fully supported using table 3.1.
4. Pursuant to Section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.
 
 
Line of Evidence (LOE) for Decision ID 118697, Azinphos-methyl (Guthion)
Region 5     
Mustang Creek (Merced County)
 
LOE ID: 68038
 
Pollutant: Azinphos-methyl (Guthion)
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 0
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Ag Waiver data for Mustang Creek (Merced County) to determine beneficial use support and results are as follows: 0 of 0 samples exceed the criterion for Azinphos methyl. Fourteen samples were not used in the assessment because the laboratory data reporting limit(s) was above the objective and therefore the results could not be quantified with the level of certainty required by the Listing Policy.
Data Reference: Data for Various Pollutants in East San Joaquin, 2004-2009.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses. (Water Quality Control Plan, Central Valley Region, Sacramento River Basin and San Joaquin River Basin)
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: The National Recommended Water Quality criterion for Azinphos Methyl (Guthion) for the protection of freshwater aquatic life is a maximum of 0.01 ug/l.
Guideline Reference: National Recommended Water Quality Criteria. United States Environmental Protection Agency. Office of Water. Office of Science and Technology
 
Spatial Representation: Data for this line of evidence for Mustang Creek (Merced County) was collected at 1 monitoring site [Mustang Creek @ East Ave - 535XMCAEA]
Temporal Representation: Data was collected over the time period 2/12/2007-4/20/2010.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: The Quality Assurance Project Plan by the East San Joaquin Water Quality Coalition, Revision 1.0 was followed.
QAPP Information Reference(s): Quality Assurance Project Plan by the East San Joaquin Water Quality Coalition, Revision 1.0.
 
Line of Evidence (LOE) for Decision ID 118697, Azinphos-methyl (Guthion)
Region 5     
Mustang Creek (Merced County)
 
LOE ID: 186491
 
Pollutant: Azinphos-methyl (Guthion)
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 0
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed East San Joaquin Water Quality Coalition data for Mustang Creek (Merced County) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Azinphos Methyl. Although a total of 2 samples were collected, 2 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline: The USEPA National Recommended Water Quality Criteria for azinphos methyl for freshwater aquatic life protection is 0.01 ug/l (instantaneous maximum)
Guideline Reference: National Recommended Water Quality Criteria. United States Environmental Protection Agency. Office of Water. Current as of 08/03/2016.
 
Spatial Representation: The samples were collected at 1 monitoring site (535XMCAEA).
Temporal Representation: Date for this waterbody was collected over the date range 2013-01-08 to 2013-02-12
Environmental Conditions:
QAPP Information: Michael L. Johnson LLC. 2015. Quality Assurance Project Plan for Monitoring by the East San Joaquin Water Quality Coalition.
QAPP Information Reference(s): Quality Assurance Project Plan for Monitoring by the East San Joaquin Water Quality Coalition
 
 
DECISION ID
125527
Region 5     
Mustang Creek (Merced County)
 
Pollutant: Bifenthrin
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: Do Not List on 303(d) list (TMDL required list)(2018)
Revision Status Revised
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: This pollutant is being considered for placement on the CWA section 303(d) List under section 3.1 of the Listing Policy. Under section 3.1a one line(s) of evidence are necessary to assess listing status.

One line of evidence is available in the administrative record to assess this pollutant. Zero of the zero samples exceed the Evaluation Guideline.

LOE 68039 has been replaced by LOE 215017 due to a reassessment of data using a U.S. EPA aquatic life benchmark.

Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the CWA section 303(d) List.

This conclusion is based on the staff findings that:
1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy.
2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy.
3. Zero of zero samples exceeded Evaluation Guideline and this sample size is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating. A minimum of 16 samples is needed to determine if a beneficial use is fully supported using table 3.1.
4. Pursuant to Section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.
 
 
Line of Evidence (LOE) for Decision ID 125527, Bifenthrin
Region 5     
Mustang Creek (Merced County)
 
LOE ID: 215017
 
Pollutant: Bifenthrin
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 0
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Six samples were collected and analyzed for Bifenthrin. The reporting level for all 6 samples is greater than the evaluation guideline value. Therefore, none of the samples were evaluated for exceedances; i.e., 0 samples, 0 exceedances.
Data Reference: Data for Various Pollutants in East San Joaquin, 2004-2009.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline: The chronic concentration goal for Bifenthrin is 0.1 ng/L (expressed as a 4-day average).  If the freely dissolved concentrations of Bifenthrin were reported or could be calculated then these values were used for this assessment.  In the absence of freely dissolved concentrations, total concentrations were used. 
Guideline Reference: Water Quality Criteria Report for Bifenthrin
Guideline Reference: Amendment to the Water Quality Control Plan for the Sacramento River and San Joaquin River Basins for the Control of Pyrethroid Pesticide Discharges
 
Spatial Representation: Data for this line of evidence for Mustang Creek (Merced County) was collected at 1 monitoring site [Mustang Creek @ East Ave - 535XMCAEA]
Temporal Representation: Data was collected over the time period 2/12/2007-2/26/2008.
Environmental Conditions:
QAPP Information: The Quality Assurance Project Plan by the East San Joaquin Water Quality Coalition, Revision 1.0 was followed.
QAPP Information Reference(s): Quality Assurance Project Plan by the East San Joaquin Water Quality Coalition, Revision 1.0.
 
 
DECISION ID
118688
Region 5     
Mustang Creek (Merced County)
 
Pollutant: Boron
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: Do Not List on 303(d) list (TMDL required list)(2018)
Revision Status Revised
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: This pollutant is being considered for placement on the CWA section 303(d) List under section 3.1 of the Listing Policy. Under section 3.1 a one line(s) of evidence are necessary to assess listing status.

Two line of evidence is available in the administrative record to assess this pollutant. Zero of the ten samples exceed the Evaluation Guideline.

Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the CWA section 303(d) List.

This conclusion is based on the staff findings that:
1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy.
2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy.
3. Zero of ten samples exceeded Evaluation Guideline and this sample size is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating. A minimum of 16 samples is needed to determine if a beneficial use is fully supported using table 3.1.
4. Pursuant to Section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.`
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of the available data and information, SWRCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because it cannot be determined if applicable water quality standards are not being exceeded.
 
 
Line of Evidence (LOE) for Decision ID 118688, Boron
Region 5     
Mustang Creek (Merced County)
 
LOE ID: 79640
 
Pollutant: Boron
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Agricultural Supply
 
Number of Samples: 8
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: State Water Board staff assessed ILRP data for Mustang Creek (Merced County) to determine beneficial use support and results are as follows: 0 of 8 samples exceed the criterion for Boron.
Data Reference: Data for Various Pollutants in East San Joaquin, 2004-2009.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Waters shall not contain chemical constituents in concentrations that adversely affect beneficial uses.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: Water Quality for Agriculture, published by the Food and Agriculture Organization of the United Nations in 1985, contains criteria protective of various agricultural uses of water, including irrigation of various types of crops and stock watering. At or below the limits presented in the Water Quality Goals tables, agricultural uses of water should not be limited. These criteria were used to translate narrative water quality objectives for chemical constituents that prohibit chemicals in concentrations that would impair agricultural uses of water. The criteria for boron is 700 ug/L (0.7 mg/L).
Guideline Reference: Water Quality for Agriculture, Food and Agriculture Organization of the United Nations - Irrigation and Drainage Paper No. 29, Rev 1, Rome (1985)
 
Spatial Representation: Data for this line of evidence for Mustang Creek (Merced County) was collected at 1 monitoring site [ Mustang Creek @ East Ave - 535XMCAEA]
Temporal Representation: Data was collected over the time period 2/7/2009-4/20/2010.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: The Quality Assurance Project Plan by the East San Joaquin Water Quality Coalition, Revision 1.0 was followed.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 118688, Boron
Region 5     
Mustang Creek (Merced County)
 
LOE ID: 186705
 
Pollutant: Boron
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Agricultural Supply
 
Number of Samples: 2
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed East San Joaquin Water Quality Coalition data for Mustang Creek (Merced County) to determine beneficial use support and results are as follows: 0 of 2 samples exceeded the water quality threshold for Boron.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Waters shall not contain chemical constituents in concentrations that adversely affect beneficial uses.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline: Water Quality for Agriculture, published by the Food and Agriculture Organization of the United Nations in 1985, contains criteria protective of various agricultural uses of water, including irrigation of various types of crops and stock watering. At or below the limits presented in the Water Quality Goals tables, agricultural uses of water should not be limited. These criteria were used to translate narrative water quality objectives for chemical constituents that prohibit chemicals in concentrations that would impair agricultural uses of water. The criteria for boron is 700 ug/L (0.7 mg/L).
Guideline Reference: Water Quality for Agriculture, Food and Agriculture Organization of the United Nations - Irrigation and Drainage Paper No. 29, Rev 1, Rome (1985)
 
Spatial Representation: The samples were collected at 1 monitoring site (535XMCAEA)
Temporal Representation: The samples were collected between the dates of 2013-01-08 and 2013-02-12
Environmental Conditions:
QAPP Information: Michael L. Johnson LLC. 2015. Quality Assurance Project Plan for Monitoring by the East San Joaquin Water Quality Coalition.
QAPP Information Reference(s): Quality Assurance Project Plan for Monitoring by the East San Joaquin Water Quality Coalition
 
 
DECISION ID
118689
Region 5     
Mustang Creek (Merced County)
 
Pollutant: Carbaryl
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: Do Not List on 303(d) list (TMDL required list)(2018)
Revision Status Revised
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available.
 
Regional Board Decision Recommendation: This decision was made by SWRCB staff.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of the available data and information, SWRCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because it cannot be determined if applicable water quality standards are not being exceeded.
 
 
Line of Evidence (LOE) for Decision ID 118689, Carbaryl
Region 5     
Mustang Creek (Merced County)
 
LOE ID: 68047
 
Pollutant: Carbaryl
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 14
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Ag Waiver data for Mustang Creek (Merced County) to determine beneficial use support and results are as follows: 0 of 14 samples exceed the criterion for Carbaryl.
Data Reference: Data for Various Pollutants in East San Joaquin, 2004-2009.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses. (Water Quality Control Plan, Central Valley Region, Sacramento River Basin and San Joaquin River Basin)
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: The USEPA recommended water quality criterion for freshwater aquatic life for carbaryl is 2.1 µg/L.
Guideline Reference: National Recommended Water Quality Criteria. United States Environmental Protection Agency. Office of Water. Office of Science and Technology
 
Spatial Representation: Data for this line of evidence for Mustang Creek (Merced County) was collected at 1 monitoring site [Mustang Creek @ East Ave - 535XMCAEA]
Temporal Representation: Data was collected over the time period 2/12/2007-4/20/2010.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: The Quality Assurance Project Plan by the East San Joaquin Water Quality Coalition, Revision 1.0 was followed.
QAPP Information Reference(s): Quality Assurance Project Plan by the East San Joaquin Water Quality Coalition, Revision 1.0.
 
Line of Evidence (LOE) for Decision ID 118689, Carbaryl
Region 5     
Mustang Creek (Merced County)
 
LOE ID: 187196
 
Pollutant: Carbaryl
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 2
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed East San Joaquin Water Quality Coalition data for Mustang Creek (Merced County) to determine beneficial use support and results are as follows: 0 of 2 samples exceeded the water quality threshold for Carbaryl.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline: The USEPA recommended water quality criteria for freshwater aquatic life for carbaryl is 2.1 µg/L.
Guideline Reference: National Recommended Water Quality Criteria. United States Environmental Protection Agency. Office of Water. Current as of 08/03/2016.
 
Spatial Representation: The samples were collected at 1 monitoring site (535XMCAEA)
Temporal Representation: The samples were collected between the dates of 2013-01-08 and 2013-02-12
Environmental Conditions:
QAPP Information: Michael L. Johnson LLC. 2015. Quality Assurance Project Plan for Monitoring by the East San Joaquin Water Quality Coalition.
QAPP Information Reference(s): Quality Assurance Project Plan for Monitoring by the East San Joaquin Water Quality Coalition
 
 
DECISION ID
118690
Region 5     
Mustang Creek (Merced County)
 
Pollutant: Carbofuran
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: Do Not List on 303(d) list (TMDL required list)(2018)
Revision Status Revised
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: This pollutant is being considered for placement on the CWA section 303(d) List under section 3.1 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status.

Four lines of evidence are available in the administrative record to assess this pollutant. Zero of the sixteen samples exceed the evaluation guideline for the Municipal and Domestic Supply beneficial use.

Insufficient information is available to evaluate the Warm and Cold Freshwater Habitat beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available.

Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the CWA section 303(d) List in the Water Quality Limited Segments category.

This conclusion is based on the staff findings that:
1. The data used for the evaluation guideline for the municipal and domestic supply beneficial use satisfies the data quality requirements of section 6.1.4 of the Policy.
2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy.
3. Zero samples exceeded the guideline for the Municipal and Domestic Supply, Warm, and Cold Freshwater habitat beneficial uses. Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy.
4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
 
Regional Board Decision Recommendation: This decision was made by SWRCB staff.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of the available data and information, SWRCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because the evaluation guideline for the Municipal and Domestic Supply beneficial use was not exceeded.

Insufficient information is available to determine Warm Freshwater Habitat and Cold Freshwater Habitat beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy.
 
 
Line of Evidence (LOE) for Decision ID 118690, Carbofuran
Region 5     
Mustang Creek (Merced County)
 
LOE ID: 68049
 
Pollutant: Carbofuran
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 14
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Ag Waiver data for Mustang Creek (Merced County) to determine beneficial use support and results are as follows: 0 of 14 samples exceed the criterion for Carbofuran.
Data Reference: Data for Various Pollutants in East San Joaquin, 2004-2009.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The California primary maximum contaminant level for Carbofuran is 18 ug/L.
Objective/Criterion Reference: Maximum Contaminant Levels for organic and inorganic chemicals. CCR Title 22
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Data for this line of evidence for Mustang Creek (Merced County) was collected at 1 monitoring site [Mustang Creek @ East Ave - 535XMCAEA]
Temporal Representation: Data was collected over the time period 2/12/2007-4/20/2010.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: The Quality Assurance Project Plan by the East San Joaquin Water Quality Coalition, Revision 1.0 was followed.
QAPP Information Reference(s): Quality Assurance Project Plan by the East San Joaquin Water Quality Coalition, Revision 1.0.
 
Line of Evidence (LOE) for Decision ID 118690, Carbofuran
Region 5     
Mustang Creek (Merced County)
 
LOE ID: 68048
 
Pollutant: Carbofuran
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 14
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Ag Waiver data for Mustang Creek (Merced County) to determine beneficial use support and results are as follows: 0 of 14 samples exceed the criterion for Carbofuran.
Data Reference: Data for Various Pollutants in East San Joaquin, 2004-2009.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses. (Water Quality Control Plan, Central Valley Region, Tulare Lake Basin)
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: The freshwater criterion maximum concentration for carbofuran is 0.5 µg/L (DFG 92-3, 1992).
Guideline Reference: Hazard Assessment of the Insecticide Carbofuran to Aquatic Organisms in the Sacramento River System
 
Spatial Representation: Data for this line of evidence for Mustang Creek (Merced County) was collected at 1 monitoring site [Mustang Creek @ East Ave - 535XMCAEA]
Temporal Representation: Data was collected over the time period 2/12/2007-4/20/2010.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: The Quality Assurance Project Plan by the East San Joaquin Water Quality Coalition, Revision 1.0 was followed.
QAPP Information Reference(s): Quality Assurance Project Plan by the East San Joaquin Water Quality Coalition, Revision 1.0.
 
Line of Evidence (LOE) for Decision ID 118690, Carbofuran
Region 5     
Mustang Creek (Merced County)
 
LOE ID: 187095
 
Pollutant: Carbofuran
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 2
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed East San Joaquin Water Quality Coalition data for Mustang Creek (Merced County) to determine beneficial use support and results are as follows: 0 of 2 samples exceeded the water quality threshold for Carbofuran.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline: The interim water quality criterion for the protection of sensitive aquatic organisms from Carbofuran is 0.5 ug/l (DFG 92-3, 1992).
Guideline Reference: Hazard Assessment of the Insecticide Carbofuran to Aquatic Organisms in the Sacramento River System
 
Spatial Representation: The samples were collected at 1 monitoring site (535XMCAEA)
Temporal Representation: The samples were collected between the dates of 2013-01-08 and 2013-02-12
Environmental Conditions:
QAPP Information: Michael L. Johnson LLC. 2015. Quality Assurance Project Plan for Monitoring by the East San Joaquin Water Quality Coalition.
QAPP Information Reference(s): Quality Assurance Project Plan for Monitoring by the East San Joaquin Water Quality Coalition
 
Line of Evidence (LOE) for Decision ID 118690, Carbofuran
Region 5     
Mustang Creek (Merced County)
 
LOE ID: 187047
 
Pollutant: Carbofuran
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 2
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed East San Joaquin Water Quality Coalition data for Mustang Creek (Merced County) to determine beneficial use support and results are as follows: 0 of 2 samples exceeded the water quality threshold for Carbofuran.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The California Primary Maximum Contaminant Level for Carbofuran incorporated by reference in the Water Quality Control Plan for the Sacramento and San Joaquin River Basins is 0.018 mg/L.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (535XMCAEA)
Temporal Representation: The samples were collected between the dates of 2013-01-08 and 2013-02-12
Environmental Conditions:
QAPP Information: Michael L. Johnson LLC. 2015. Quality Assurance Project Plan for Monitoring by the East San Joaquin Water Quality Coalition.
QAPP Information Reference(s): Quality Assurance Project Plan for Monitoring by the East San Joaquin Water Quality Coalition
 
 
DECISION ID
118714
Region 5     
Mustang Creek (Merced County)
 
Pollutant: Cyanazine
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: Do Not List on 303(d) list (TMDL required list)(2018)
Revision Status Revised
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: This pollutant is being considered for placement on the CWA section 303(d) List under section 3.1 of the Listing Policy. Under section 3.1 a two line(s) of evidence are necessary to assess listing status.

Two line of evidence is available in the administrative record to assess this pollutant. Zero of the 14 samples exceed the Evaluation Guideline for Warm Freshwater Habitat. Zero of the 2 samples exceed the Evaluation Guideline for Cold Freshwater Habitat.

Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the CWA section 303(d) List.

This conclusion is based on the staff findings that:
1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy.
2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy.
3. Zero of 14 for Warm Freshwater Habitat and 0 of 2 for Cold Freshwater Habitat samples exceeded Evaluation Guideline and this sample size is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating. A minimum of 16 samples is needed to determine if a beneficial use is fully supported using table 3.1.
4. Pursuant to Section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
 
Regional Board Decision Recommendation: This decision was made by SWRCB staff.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of the available data and information, SWRCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because it cannot be determined if applicable water quality standards are not being exceeded.
 
 
Line of Evidence (LOE) for Decision ID 118714, Cyanazine
Region 5     
Mustang Creek (Merced County)
 
LOE ID: 68057
 
Pollutant: Cyanazine
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 14
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Ag Waiver data for Mustang Creek (Merced County) to determine beneficial use support and results are as follows: 0 of 14 samples exceed the criterion for Cyanazine.
Data Reference: Data for Various Pollutants in East San Joaquin, 2004-2009.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses. (Water Quality Control Plan, Central Valley Region, Sacramento River Basin and San Joaquin River Basin)
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: The EC50 for Navicula pelliculosa (freshwater diatom) for cyanazine is 4.8 ug/L (USEPA Office of Pesticide Programs Ecotoxicity database).
Guideline Reference: OPP Pesticide Ecotoxicity Database.
 
Spatial Representation: Data for this line of evidence for Mustang Creek (Merced County) was collected at 1 monitoring site [Mustang Creek @ East Ave - 535XMCAEA]
Temporal Representation: Data was collected over the time period 2/12/2007-4/20/2010.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: The Quality Assurance Project Plan by the East San Joaquin Water Quality Coalition, Revision 1.0 was followed.
QAPP Information Reference(s): Quality Assurance Project Plan by the East San Joaquin Water Quality Coalition, Revision 1.0.
 
Line of Evidence (LOE) for Decision ID 118714, Cyanazine
Region 5     
Mustang Creek (Merced County)
 
LOE ID: 187787
 
Pollutant: Cyanazine
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 2
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed East San Joaquin Water Quality Coalition data for Mustang Creek (Merced County) to determine beneficial use support and results are as follows: 0 of 2 samples exceeded the water quality threshold for Cyanazine.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Water Quality Control Plan for the Sacramento and San Joaquin River Basins).
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline: The evaluation guideline for cyanazine is the EC50 of 4.8 ug/L for Navicula pelliculosa (freshwater diatom) (USEPA Office of Pesticide Programs Ecotoxicity database).
Guideline Reference: OPP Pesticide Ecotoxicity Database.
 
Spatial Representation: The samples were collected at 1 monitoring site (535XMCAEA)
Temporal Representation: The samples were collected between the dates of 2013-01-08 and 2013-02-12
Environmental Conditions:
QAPP Information: Michael L. Johnson LLC. 2015. Quality Assurance Project Plan for Monitoring by the East San Joaquin Water Quality Coalition.
QAPP Information Reference(s): Quality Assurance Project Plan for Monitoring by the East San Joaquin Water Quality Coalition
 
 
DECISION ID
125529
Region 5     
Mustang Creek (Merced County)
 
Pollutant: Cyfluthrin
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: Do Not List on 303(d) list (TMDL required list)(2018)
Revision Status Revised
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: Previously considered water quality data was reevaluated according to new guidelines as part of this assessment. Line of evidence #68058 was replaced by #215018.

Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.
 
 
Line of Evidence (LOE) for Decision ID 125529, Cyfluthrin
Region 5     
Mustang Creek (Merced County)
 
LOE ID: 215018
 
Pollutant: Cyfluthrin
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 0
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Ag Waiver data for Mustang Creek (Merced County) to determine beneficial use support and results are as follows: 0 of 0 samples exceed the criterion for Cyfluthrin, total. Six samples were not used in the assessment because the laboratory data reporting limit(s) was above the objective and therefore the results could not be quantified with the level of certainty required by the Listing Policy.
Data Reference: Data for Various Pollutants in East San Joaquin, 2004-2009.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline: The chronic concentration goal for Cyfluthrin is 0.2 ng/L (expressed as a 4-day average).  If the freely dissolved concentrations of Cyfluthrin were reported or could be calculated then these values were used for this assessment.  In the absence of freely dissolved concentrations, total concentrations were used.
Guideline Reference: Water Quality Criteria Report for Bifenthrin
Guideline Reference: Amendment to the Water Quality Control Plan for the Sacramento River and San Joaquin River Basins for the Control of Pyrethroid Pesticide Discharges
 
Spatial Representation: Data for this line of evidence for Mustang Creek (Merced County) was collected at 1 monitoring site [Mustang Creek @ East Ave - 535XMCAEA]
Temporal Representation: Data was collected over the time period 2/12/2007-2/26/2008.
Environmental Conditions:
QAPP Information: The Quality Assurance Project Plan by the East San Joaquin Water Quality Coalition, Revision 1.0 was followed.
QAPP Information Reference(s): Quality Assurance Project Plan by the East San Joaquin Water Quality Coalition, Revision 1.0.
 
 
DECISION ID
125530
Region 5     
Mustang Creek (Merced County)
 
Pollutant: Cyhalothrin, Lambda
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: Do Not List on 303(d) list (TMDL required list)(2018)
Revision Status Revised
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available. LOE 68059 has been replaced by LOE 215015 due to a reassessment of data using a U.S. EPA aquatic life benchmark.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.
 
 
Line of Evidence (LOE) for Decision ID 125530, Cyhalothrin, Lambda
Region 5     
Mustang Creek (Merced County)
 
LOE ID: 215015
 
Pollutant: Cyhalothrin, Lambda
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 0
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Ag Waiver data for Mustang Creek (Merced County) to determine beneficial use support and results are as follows: 0 of 0 samples exceed the criterion for Cyhalothrin, lambda. Six samples were not used in the assessment because the laboratory data reporting limit(s) was above the objective and therefore the results could not be quantified with the level of certainty required by the Listing Policy.
Data Reference: Data for Various Pollutants in East San Joaquin, 2004-2009.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline: The chronic concentration goal for Lambda-cyhalothrin is 0.3 ng/L (expressed as a 4-day average).  If the freely dissolved concentrations of Lambda-cyhalothrin were reported or could be calculated then these values were used for this assessment.  In the absence of freely dissolved concentrations, total concentrations were used.
Guideline Reference: Water Quality Criteria Report for Lambda-cyhalothrin
Guideline Reference: Amendment to the Water Quality Control Plan for the Sacramento River and San Joaquin River Basins for the Control of Pyrethroid Pesticide Discharges
 
Spatial Representation: Data for this line of evidence for Mustang Creek (Merced County) was collected at 1 monitoring site [Mustang Creek @ East Ave - 535XMCAEA]
Temporal Representation: Data was collected over the time period 2/12/2007-2/26/2008.
Environmental Conditions:
QAPP Information: The Quality Assurance Project Plan by the East San Joaquin Water Quality Coalition, Revision 1.0 was followed.
QAPP Information Reference(s): Quality Assurance Project Plan by the East San Joaquin Water Quality Coalition, Revision 1.0.
 
 
DECISION ID
125528
Region 5     
Mustang Creek (Merced County)
 
Pollutant: Cypermethrin
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: Do Not List on 303(d) list (TMDL required list)(2018)
Revision Status Revised
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: Previously considered water quality data was reevaluated according to new guidelines as part of this assessment. Line of evidence #68060 was replaced by #215016.

Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.
 
 
Line of Evidence (LOE) for Decision ID 125528, Cypermethrin
Region 5     
Mustang Creek (Merced County)
 
LOE ID: 215016
 
Pollutant: Cypermethrin
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 0
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Ag Waiver data for Mustang Creek (Merced County) to determine beneficial use support and results are as follows: 0 of 0 samples exceed the criterion for Cypermethrin, total. Six samples were not used in the assessment because the laboratory data reporting limit(s) was above the objective and therefore the results could not be quantified with the level of certainty required by the Listing Policy.
Data Reference: Data for Various Pollutants in East San Joaquin, 2004-2009.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline: The chronic concentration goal for Cypermethrin is 0.3 ng/L (expressed as a 4-day average).  If the freely dissolved concentrations of Cypermethrin were reported or could be calculated then these values were used for this assessment.  In the absence of freely dissolved concentrations, total concentrations were used.
Guideline Reference: Water Quality Criteria Report for Cypermethrin
Guideline Reference: Amendment to the Water Quality Control Plan for the Sacramento River and San Joaquin River Basins for the Control of Pyrethroid Pesticide Discharges
 
Spatial Representation: Data for this line of evidence for Mustang Creek (Merced County) was collected at 1 monitoring site [Mustang Creek @ East Ave - 535XMCAEA]
Temporal Representation: Data was collected over the time period 2/12/2007-2/26/2008.
Environmental Conditions:
QAPP Information: The Quality Assurance Project Plan by the East San Joaquin Water Quality Coalition, Revision 1.0 was followed.
QAPP Information Reference(s): Quality Assurance Project Plan by the East San Joaquin Water Quality Coalition, Revision 1.0.
 
 
DECISION ID
118718
Region 5     
Mustang Creek (Merced County)
 
Pollutant: Demeton
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: New Decision
Revision Status Revised
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available.
 
Regional Board Decision Recommendation: This decision was made by SWRCB staff.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of the available data and information, SWRCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because it cannot be determined if applicable water quality standards are not being exceeded.
 
 
Line of Evidence (LOE) for Decision ID 118718, Demeton
Region 5     
Mustang Creek (Merced County)
 
LOE ID: 188527
 
Pollutant: Demeton
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 2
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed East San Joaquin Water Quality Coalition data for Mustang Creek (Merced County) to determine beneficial use support and results are as follows: 0 of 2 samples exceeded the water quality threshold for Demeton, Total.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline: The USEPA National Recommended Water Quality Criteria toxicity threshold for demeton for freshwater aquatic life protection is 0.1 ug/l (4 day average)
Guideline Reference: National Recommended Water Quality Criteria. United States Environmental Protection Agency. Office of Water. Current as of 08/03/2016.
 
Spatial Representation: The samples were collected at 1 monitoring site (535XMCAEA)
Temporal Representation: The samples were collected between the dates of 2013-01-08 and 2013-02-12
Environmental Conditions:
QAPP Information: Michael L. Johnson LLC. 2015. Quality Assurance Project Plan for Monitoring by the East San Joaquin Water Quality Coalition.
QAPP Information Reference(s): Quality Assurance Project Plan for Monitoring by the East San Joaquin Water Quality Coalition
 
 
DECISION ID
118694
Region 5     
Mustang Creek (Merced County)
 
Pollutant: Dichlorvos
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: New Decision
Revision Status Revised
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of the available data and information, SWRCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because it cannot be determined if applicable water quality standards are not being exceeded.
 
 
Line of Evidence (LOE) for Decision ID 118694, Dichlorvos
Region 5     
Mustang Creek (Merced County)
 
LOE ID: 188811
 
Pollutant: Dichlorvos
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 0
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed East San Joaquin Water Quality Coalition data for Mustang Creek (Merced County) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Dichlorvos. Although a total of 2 samples were collected, 2 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Water Quality Control Plan for the Sacramento and San Joaquin River Basins).
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline: The evaluation guideline for Dichlorvos is the USEPA Aquatic Life Benchmark of 0.0058 ug/L for a invertebrate (acute).
Guideline Reference: OPP Aquatic Life Benchmarks
 
Spatial Representation: The samples were collected at 1 monitoring site (535XMCAEA).
Temporal Representation: Date for this waterbody was collected over the date range 2013-01-08 to 2013-02-12
Environmental Conditions:
QAPP Information: Michael L. Johnson LLC. 2015. Quality Assurance Project Plan for Monitoring by the East San Joaquin Water Quality Coalition.
QAPP Information Reference(s): Quality Assurance Project Plan for Monitoring by the East San Joaquin Water Quality Coalition
 
 
DECISION ID
128785
Region 5     
Mustang Creek (Merced County)
 
Pollutant: Dicofol
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: Do Not List on 303(d) list (TMDL required list)(2018)
Revision Status Revised
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available. LOE 68069 has been replaced by LOE 221664 due to a reassessment of data using a U.S. EPA aquatic life benchmark.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.
 
 
Line of Evidence (LOE) for Decision ID 128785, Dicofol
Region 5     
Mustang Creek (Merced County)
 
LOE ID: 221664
 
Pollutant: Dicofol
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 12
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed ILRP_ESJWQC data for Mustang Creek (Merced County) to determine beneficial use support and results are as follows: 0 of 12 samples exceeded the water quality threshold for Dicofol.
Data Reference: Data for Various Pollutants in East San Joaquin, 2004-2009.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Water Quality Control Plan for the Sacramento and San Joaquin River Basins).
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline: The evaluation guideline for Dicofol is the USEPA Aquatic Life Benchmark of 4.4 ug/L for a fish (chronic).
Guideline Reference: OPP Aquatic Life Benchmarks
 
Spatial Representation: The samples were collected at 1 monitoring site (535XMCAEA)
Temporal Representation: The samples were collected between the dates of 2006-05-18 and 2009-12-15
Environmental Conditions:
QAPP Information: The Quality Assurance Project Plan by the East San Joaquin Water Quality Coalition, Revision 1.0 was followed.
QAPP Information Reference(s): Quality Assurance Project Plan by the East San Joaquin Water Quality Coalition, Revision 1.0.
 
 
DECISION ID
118713
Region 5     
Mustang Creek (Merced County)
 
Pollutant: Dimethoate
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: Do Not List on 303(d) list (TMDL required list)(2018)
Revision Status Revised
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: This pollutant is being considered for placement on the CWA section 303(d) List under section 3.1 of the Listing Policy.

Zero samples exceeded the objectives, guidelines, or criteria for beneficial uses applicable to this water segment-pollutant combination, which is less than the minimum number of exceedances needed to place the water segment on the section CWA section 303(d) List for toxicants (Table 3.1 of the Listing Policy).

LOE 68077 has been replaced by LOE 221579 due to a reassessment of data using a U.S. EPA aquatic life benchmark.

The data used satisfies the data quality requirements (section 6.1.4) and data quantity requirements (section 6.1.5) of the Listing Policy.

Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the CWA section 303(d) List.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because applicable water quality standards are not being exceeded.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.
 
 
Line of Evidence (LOE) for Decision ID 118713, Dimethoate
Region 5     
Mustang Creek (Merced County)
 
LOE ID: 221579
 
Pollutant: Dimethoate
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 17
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed ILRP_ESJWQC data for Mustang Creek (Merced County) to determine beneficial use support and results are as follows: 0 of 17 samples exceeded the water quality threshold for Dimethoate.
Data Reference: Data for Various Pollutants in East San Joaquin, 2004-2009.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Water Quality Control Plan for the Sacramento and San Joaquin River Basins).
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline: The evaluation guideline for Dimethoate is the USEPA Aquatic Life Benchmark of 0.5 ug/L for a invertebrate (acute).
Guideline Reference: OPP Aquatic Life Benchmarks
 
Spatial Representation: The samples were collected at 1 monitoring site (535XMCAEA)
Temporal Representation: The samples were collected between the dates of 2006-05-18 and 2010-04-20
Environmental Conditions:
QAPP Information: The Quality Assurance Project Plan by the East San Joaquin Water Quality Coalition, Revision 1.0 was followed.
QAPP Information Reference(s): Quality Assurance Project Plan by the East San Joaquin Water Quality Coalition, Revision 1.0.
 
Line of Evidence (LOE) for Decision ID 118713, Dimethoate
Region 5     
Mustang Creek (Merced County)
 
LOE ID: 189103
 
Pollutant: Dimethoate
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 2
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed East San Joaquin Water Quality Coalition data for Mustang Creek (Merced County) to determine beneficial use support and results are as follows: 0 of 2 samples exceeded the water quality threshold for Dimethoate.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Water Quality Control Plan for the Sacramento and San Joaquin River Basins).
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline: The evaluation guideline for Dimethoate is the USEPA Aquatic Life Benchmark of 0.5 ug/L for a invertebrate (acute).
Guideline Reference: OPP Aquatic Life Benchmarks
 
Spatial Representation: The samples were collected at 1 monitoring site (535XMCAEA)
Temporal Representation: The samples were collected between the dates of 2013-01-08 and 2013-02-12
Environmental Conditions:
QAPP Information: Michael L. Johnson LLC. 2015. Quality Assurance Project Plan for Monitoring by the East San Joaquin Water Quality Coalition.
QAPP Information Reference(s): Quality Assurance Project Plan for Monitoring by the East San Joaquin Water Quality Coalition
 
 
DECISION ID
118695
Region 5     
Mustang Creek (Merced County)
 
Pollutant: Disulfoton
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: Do Not List on 303(d) list (TMDL required list)(2018)
Revision Status Revised
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: This pollutant is being considered for placement on the CWA section 303(d) List under section 3.1 of the Listing Policy. Under section 3.1 a one line(s) of evidence are necessary to assess listing status.

Two lines of evidence is available in the administrative record to assess this pollutant. Zero of the eight samples exceed the Evaluation Guideline for WARM. Zero of zero samples exceed the Evaluation Guideline for COLD.

Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the CWA section 303(d) List.

This conclusion is based on the staff findings that:
1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy.
2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy.
3. Zero of the eight samples exceed the Evaluation Guideline for WARM. Zero of zero samples exceed the Evaluation Guideline for COLD. This sample size is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating. A minimum of 16 samples is needed to determine if a beneficial use is fully supported using table 3.1.
4. Pursuant to Section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
 
Regional Board Decision Recommendation: This decision was made by SWRCB staff.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of the available data and information, SWRCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because it cannot be determined if applicable water quality standards are not being exceeded.
 
 
Line of Evidence (LOE) for Decision ID 118695, Disulfoton
Region 5     
Mustang Creek (Merced County)
 
LOE ID: 68078
 
Pollutant: Disulfoton
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 8
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Ag Waiver data for Mustang Creek (Merced County) to determine beneficial use support and results are as follows: 0 of 8 samples exceed the criterion for Disulfoton.
Data Reference: Data for Various Pollutants in East San Joaquin, 2004-2009.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses. (Water Quality Control Plan, Central Valley Region, Sacramento River Basin and San Joaquin River Basin)
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: The USEPA National Recommended Water Quality criterion for disulfoton in freshwater (0.05 ug/L) is an aquatic life maximum (instantaneous) level.
Guideline Reference: National Recommended Water Quality Criteria. United States Environmental Protection Agency. Office of Water. Office of Science and Technology
 
Spatial Representation: Data for this line of evidence for Mustang Creek (Merced County) was collected at 1 monitoring site [Mustang Creek @ East Ave - 535XMCAEA]
Temporal Representation: Data was collected over the time period 2/12/2007-4/20/2010.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: The Quality Assurance Project Plan by the East San Joaquin Water Quality Coalition, Revision 1.0 was followed.
QAPP Information Reference(s): Quality Assurance Project Plan by the East San Joaquin Water Quality Coalition, Revision 1.0.
 
Line of Evidence (LOE) for Decision ID 118695, Disulfoton
Region 5     
Mustang Creek (Merced County)
 
LOE ID: 189132
 
Pollutant: Disulfoton
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 0
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed East San Joaquin Water Quality Coalition data for Mustang Creek (Merced County) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Disulfoton. Although a total of 2 samples were collected, 2 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline: The evaluation guideline for disulfoton is the USEPA Aquatic Life Benchmark of 0.01 ug/L for chronic toxicity in invertebrates (7 day average).
Guideline Reference: OPP Aquatic Life Benchmarks
 
Spatial Representation: The samples were collected at 1 monitoring site (535XMCAEA).
Temporal Representation: Date for this waterbody was collected over the date range 2013-01-08 to 2013-02-12
Environmental Conditions:
QAPP Information: Michael L. Johnson LLC. 2015. Quality Assurance Project Plan for Monitoring by the East San Joaquin Water Quality Coalition.
QAPP Information Reference(s): Quality Assurance Project Plan for Monitoring by the East San Joaquin Water Quality Coalition
 
 
DECISION ID
118696
Region 5     
Mustang Creek (Merced County)
 
Pollutant: Diuron
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: Do Not List on 303(d) list (TMDL required list)(2018)
Revision Status Revised
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: This pollutant is being considered for placement on the CWA section 303(d) List under section 3.1 of the Listing Policy. Under section 3.1, a single line of evidence is necessary to assess listing status. One line of evidence is available in the administrative record to assess this pollutant. Zero of 14 samples and 0 of 2 samples exceed the evaluation guideline for the Warm Freshwater Habitat and Cold Freshwater Habitat beneficial use.

Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the CWA section 303(d) List.

This conclusion is based on the staff findings that:
1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy.
2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy.
3. Zero of 14 and 0 of 2 water sample results exceed the evaluation guideline for the Warm Freshwater Habitat beneficial use, and this sample size is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating. A minimum of 16 samples is needed to determine if a beneficial use is fully supported using table 3.1.
4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
 
Regional Board Decision Recommendation: This decision was made by SWRCB staff.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of the available data and information, SWRCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because it cannot be determined if applicable water quality standards are not being exceeded.
 
 
Line of Evidence (LOE) for Decision ID 118696, Diuron
Region 5     
Mustang Creek (Merced County)
 
LOE ID: 189049
 
Pollutant: Diuron
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 2
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed East San Joaquin Water Quality Coalition data for Mustang Creek (Merced County) to determine beneficial use support and results are as follows: 0 of 2 samples exceeded the water quality threshold for Diuron.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline: Aquatic life should not be affected unacceptably if the 4-day average concentration of diuron does not exceed 1.3 ug/L (UC Davis Aquatic Life Criteria).
Guideline Reference: Aquatic life water quality criteria derived via the UC Davis method: III. Diuron. Reviews of Environmental Contamination and Toxicology 216:105-141.
 
Spatial Representation: The samples were collected at 1 monitoring site (535XMCAEA)
Temporal Representation: The samples were collected between the dates of 2013-01-08 and 2013-02-12
Environmental Conditions:
QAPP Information: Michael L. Johnson LLC. 2015. Quality Assurance Project Plan for Monitoring by the East San Joaquin Water Quality Coalition.
QAPP Information Reference(s): Quality Assurance Project Plan for Monitoring by the East San Joaquin Water Quality Coalition
 
Line of Evidence (LOE) for Decision ID 118696, Diuron
Region 5     
Mustang Creek (Merced County)
 
LOE ID: 79642
 
Pollutant: Diuron
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 14
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: State Water Board staff assessed ILRP data for Mustang Creek (Merced County) to determine beneficial use support and results are as follows: 0 of 14 samples exceed the criterion for Diuron.
Data Reference: Data for Various Pollutants in East San Joaquin, 2004-2009.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan, Central Valley Region Sacramento River Basin and San Joaquin River Basin: No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: The Basin Plan states: "Where valid testing has developed 96-hour LC50 values for aquatic organisms..., the Board will consider one tenth of this value for the most sensitive species tested as the upper limit (daily maximum) for the protection of aquatic life... or [O]ther available information on the pesticide..." Aquatic life should not be affected unacceptably if the 4-day average concentration of Diuron, 1.3 ug/L, is not exceeded more than once every three years on the average (UC Davis Aquatic Life Criterion).
Guideline Reference: Aquatic life water quality criteria derived via the UC Davis method: III. Diuron. Reviews of Environmental Contamination and Toxicology 216:105-141.
 
Spatial Representation: Data for this line of evidence for Mustang Creek (Merced County) was collected at 1 monitoring site [ Mustang Creek @ East Ave - 535XMCAEA]
Temporal Representation: Data was collected over the time period 2/12/2007-4/20/2010.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: The Quality Assurance Project Plan by the East San Joaquin Water Quality Coalition, Revision 1.0 was followed.
QAPP Information Reference(s):
 
 
DECISION ID
125531
Region 5     
Mustang Creek (Merced County)
 
Pollutant: Esfenvalerate/Fenvalerate
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: Do Not List on 303(d) list (TMDL required list)(2018)
Revision Status Revised
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: Previously considered water quality data was reevaluated according to new guidelines as part of this assessment. Line of evidence #68087 was replaced by #215032.

Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.
 
 
Line of Evidence (LOE) for Decision ID 125531, Esfenvalerate/Fenvalerate
Region 5     
Mustang Creek (Merced County)
 
LOE ID: 215032
 
Pollutant: Esfenvalerate/Fenvalerate
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 6
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Ag Waiver data for Mustang Creek (Merced County) to determine beneficial use support and results are as follows: 0 of 6 samples exceed the criterion for Esfenvalerate/Fenvalerate.
Data Reference: Data for Various Pollutants in East San Joaquin, 2004-2009.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline: The chronic concentration goal for Esfenvalerate is 0.3 ng/L (expressed as a 4-day average).  If the freely dissolved concentrations of Esfenvalerate were reported or could be calculated then these values were used for this assessment.  In the absence of freely dissolved concentrations, total concentrations were used. The evaluation guideline for fenvalerate, 0.113 ug/L, is one-tenth of the median lethal concentration (LC50 = 1.13 ug/L) as determined in a 96 hour toxicity test using the fathead minnow, Pimephales promelas. (USEPA OPP Ecotoxicity database)
Guideline Reference: OPP Pesticide Ecotoxicity Database.
Guideline Reference: Water Quality Criteria Report for Esfenvalerate
Guideline Reference: Amendment to the Water Quality Control Plan for the Sacramento River and San Joaquin River Basins for the Control of Pyrethroid Pesticide Discharges
 
Spatial Representation: Data for this line of evidence for Mustang Creek (Merced County) was collected at 1 monitoring site [Mustang Creek @ East Ave - 535XMCAEA]
Temporal Representation: Data was collected over the time period 2/12/2007-2/26/2008.
Environmental Conditions:
QAPP Information: The Quality Assurance Project Plan by the East San Joaquin Water Quality Coalition, Revision 1.0 was followed.
QAPP Information Reference(s): Quality Assurance Project Plan by the East San Joaquin Water Quality Coalition, Revision 1.0.
 
 
DECISION ID
128786
Region 5     
Mustang Creek (Merced County)
 
Pollutant: Glyphosate
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: Do Not List on 303(d) list (TMDL required list)(2018)
Revision Status Revised
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available.

LOE 68088 has been replaced by LOE 221961due to a reassessment of data using a U.S. EPA aquatic life benchmark.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.
 
 
Line of Evidence (LOE) for Decision ID 128786, Glyphosate
Region 5     
Mustang Creek (Merced County)
 
LOE ID: 221961
 
Pollutant: Glyphosate
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 12
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed ILRP_ESJWQC data for Mustang Creek (Merced County) to determine beneficial use support and results are as follows: 0 of 12 samples exceeded the water quality threshold for Glyphosate.
Data Reference: Data for Various Pollutants in East San Joaquin, 2004-2009.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Water Quality Control Plan for the Sacramento and San Joaquin River Basins).
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline: The evaluation guideline for Glyphosate is the USEPA Aquatic Life Benchmark of 11900 ug/L for a vascular plant (acute).
Guideline Reference: OPP Aquatic Life Benchmarks
 
Spatial Representation: The samples were collected at 1 monitoring site (535XMCAEA)
Temporal Representation: The samples were collected between the dates of 2006-05-18 and 2009-12-15
Environmental Conditions:
QAPP Information: The Quality Assurance Project Plan by the East San Joaquin Water Quality Coalition, Revision 1.0 was followed.
QAPP Information Reference(s): Quality Assurance Project Plan by the East San Joaquin Water Quality Coalition, Revision 1.0.
 
Line of Evidence (LOE) for Decision ID 128786, Glyphosate
Region 5     
Mustang Creek (Merced County)
 
LOE ID: 68089
 
Pollutant: Glyphosate
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 9
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Ag Waiver data for Mustang Creek (Merced County) to determine beneficial use support and results are as follows: 0 of 9 samples exceed the criterion for Glyphosate.
Data Reference: Data for Various Pollutants in East San Joaquin, 2004-2009.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The California primary maximum contaminant level for Glyphosate is 700 ug/L.
Objective/Criterion Reference: Maximum Contaminant Levels for organic and inorganic chemicals. CCR Title 22
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Data for this line of evidence for Mustang Creek (Merced County) was collected at 1 monitoring site [Mustang Creek @ East Ave - 535XMCAEA]
Temporal Representation: Data was collected over the time period 2/12/2007-12/15/2009.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: The Quality Assurance Project Plan by the East San Joaquin Water Quality Coalition, Revision 1.0 was followed.
QAPP Information Reference(s): Quality Assurance Project Plan by the East San Joaquin Water Quality Coalition, Revision 1.0.
 
 
DECISION ID
118698
Region 5     
Mustang Creek (Merced County)
 
Pollutant: Linuron
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: Do Not List on 303(d) list (TMDL required list)(2018)
Revision Status Revised
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available.

LOE 68096 has been replaced by LOE 221924 due to a reassessment of data using a U.S. EPA aquatic life benchmark.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.
 
 
Line of Evidence (LOE) for Decision ID 118698, Linuron
Region 5     
Mustang Creek (Merced County)
 
LOE ID: 221924
 
Pollutant: Linuron
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 0
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed ILRP_ESJWQC data for Mustang Creek (Merced County) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Linuron. Although a total of 17 samples were collected, 17 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference: Data for Various Pollutants in East San Joaquin, 2004-2009.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Water Quality Control Plan for the Sacramento and San Joaquin River Basins).
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline: The evaluation guideline for Linuron is the USEPA Aquatic Life Benchmark of 0.09 ug/L for a invertebrate (acute).
Guideline Reference: OPP Aquatic Life Benchmarks
 
Spatial Representation: The samples were collected at 1 monitoring site (535XMCAEA).
Temporal Representation: Date for this waterbody was collected over the date range 2006-05-18 to 2010-04-20
Environmental Conditions:
QAPP Information: The Quality Assurance Project Plan by the East San Joaquin Water Quality Coalition, Revision 1.0 was followed.
QAPP Information Reference(s): Quality Assurance Project Plan by the East San Joaquin Water Quality Coalition, Revision 1.0.
 
Line of Evidence (LOE) for Decision ID 118698, Linuron
Region 5     
Mustang Creek (Merced County)
 
LOE ID: 191228
 
Pollutant: Linuron
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 0
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed East San Joaquin Water Quality Coalition data for Mustang Creek (Merced County) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Linuron. Although a total of 2 samples were collected, 2 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Water Quality Control Plan for the Sacramento and San Joaquin River Basins).
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline: The evaluation guideline for Linuron is the USEPA Aquatic Life Benchmark of 0.09 ug/L for a invertebrate (acute).
Guideline Reference: OPP Aquatic Life Benchmarks
 
Spatial Representation: The samples were collected at 1 monitoring site (535XMCAEA).
Temporal Representation: Date for this waterbody was collected over the date range 2013-01-08 to 2013-02-12
Environmental Conditions:
QAPP Information: Michael L. Johnson LLC. 2015. Quality Assurance Project Plan for Monitoring by the East San Joaquin Water Quality Coalition.
QAPP Information Reference(s): Quality Assurance Project Plan for Monitoring by the East San Joaquin Water Quality Coalition
 
 
DECISION ID
118699
Region 5     
Mustang Creek (Merced County)
 
Pollutant: Malathion
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: Do Not List on 303(d) list (TMDL required list)(2018)
Revision Status Revised
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: This pollutant is being considered for placement on the CWA section 303(d) List under section 3.1 of the Listing Policy. Under section 3.1a one line(s) of evidence are necessary to assess listing status.

One line of evidence is available in the administrative record to assess this pollutant. Zero of the zero samples exceed the Evaluation Guideline.

Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the CWA section 303(d) List.

This conclusion is based on the staff findings that:
1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy.
2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy.
3. Zero of zero samples exceeded Evaluation Guideline and this sample size is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating. A minimum of 16 samples is needed to determine if a beneficial use is fully supported using table 3.1.
4. Pursuant to Section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.
 
 
Line of Evidence (LOE) for Decision ID 118699, Malathion
Region 5     
Mustang Creek (Merced County)
 
LOE ID: 191132
 
Pollutant: Malathion
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 0
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed East San Joaquin Water Quality Coalition data for Mustang Creek (Merced County) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Malathion. Although a total of 2 samples were collected, 2 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline: Aquatic life should not be affected unacceptably if the 4-day average concentration of malathion does not exceed 0.028 ug/L (UC Davis Aquatic Life Criteria).
Guideline Reference: Aquatic life water quality criteria derived via the UC Davis method: l. Organophosphate insecticides. Reviews of Environmental Contamination and Toxicology 216:1-48.
 
Spatial Representation: The samples were collected at 1 monitoring site (535XMCAEA).
Temporal Representation: Date for this waterbody was collected over the date range 2013-01-08 to 2013-02-12
Environmental Conditions:
QAPP Information: Michael L. Johnson LLC. 2015. Quality Assurance Project Plan for Monitoring by the East San Joaquin Water Quality Coalition.
QAPP Information Reference(s): Quality Assurance Project Plan for Monitoring by the East San Joaquin Water Quality Coalition
 
Line of Evidence (LOE) for Decision ID 118699, Malathion
Region 5     
Mustang Creek (Merced County)
 
LOE ID: 68097
 
Pollutant: Malathion
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 0
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Ag Waiver data for Mustang Creek (Merced County) to determine beneficial use support and results are as follows: 0 of 0 samples exceed the criterion for Malathion. Fourteen samples were not used in the assessment because the laboratory data reporting limit(s) was above the objective and therefore the results could not be quantified with the level of certainty required by the Listing Policy.
Data Reference: Data for Various Pollutants in East San Joaquin, 2004-2009.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses. (Water Quality Control Plan, Central Valley Region, Sacramento River Basin and San Joaquin River Basin)
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: The Basin Plan states: "Where valid testing has developed 96-hour LC50 values for aquatic organisms..., the Board will consider one tenth of this value for the most sensitive species tested as the upper limit (daily maximum) for the protection of aquatic life... or [O]ther available information on the pesticide..." Aquatic life should not be affected unacceptably if the 4-day average concentration of Malathion, 0.028 ug/L, is not exceeded more than once every three years on the average (UC Davis Aquatic Life Criterion).
Guideline Reference: OPP Pesticide Ecotoxicity Database.
 
Spatial Representation: Data for this line of evidence for Mustang Creek (Merced County) was collected at 1 monitoring site [Mustang Creek @ East Ave - 535XMCAEA]
Temporal Representation: Data was collected over the time period 2/12/2007-4/20/2010.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: The Quality Assurance Project Plan by the East San Joaquin Water Quality Coalition, Revision 1.0 was followed.
QAPP Information Reference(s): Quality Assurance Project Plan by the East San Joaquin Water Quality Coalition, Revision 1.0.
 
 
DECISION ID
118712
Region 5     
Mustang Creek (Merced County)
 
Pollutant: Methidathion
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: Do Not List on 303(d) list (TMDL required list)(2018)
Revision Status Revised
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: This pollutant is being considered for placement on the CWA section 303(d) List under section 3.1 of the Listing Policy.

Zero samples exceeded the objectives, guidelines, or criteria for beneficial uses applicable to this water segment-pollutant combination, which is less than the minimum number of exceedances needed to place the water segment on the section CWA section 303(d) List for toxicants (Table 3.1 of the Listing Policy).

The data used satisfies the data quality requirements (section 6.1.4) and data quantity requirements (section 6.1.5) of the Listing Policy.

Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the CWA section 303(d) List.

LOE 68098 has been replaced by LOE 221847 due to a reassessment of data using a U.S. EPA aquatic life benchmark.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because applicable water quality standards are not being exceeded.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.
 
 
Line of Evidence (LOE) for Decision ID 118712, Methidathion
Region 5     
Mustang Creek (Merced County)
 
LOE ID: 221847
 
Pollutant: Methidathion
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 17
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed ILRP_ESJWQC data for Mustang Creek (Merced County) to determine beneficial use support and results are as follows: 0 of 17 samples exceeded the water quality threshold for Methidathion.
Data Reference: Data for Various Pollutants in East San Joaquin, 2004-2009.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Water Quality Control Plan for the Sacramento and San Joaquin River Basins).
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline: The evaluation guideline for Methidathion is the USEPA Aquatic Life Benchmark of 0.66 ug/L for a invertebrate (acute).
Guideline Reference: OPP Aquatic Life Benchmarks
 
Spatial Representation: The samples were collected at 1 monitoring site (535XMCAEA)
Temporal Representation: The samples were collected between the dates of 2006-05-18 and 2010-04-20
Environmental Conditions:
QAPP Information: The Quality Assurance Project Plan by the East San Joaquin Water Quality Coalition, Revision 1.0 was followed.
QAPP Information Reference(s): Quality Assurance Project Plan by the East San Joaquin Water Quality Coalition, Revision 1.0.
 
Line of Evidence (LOE) for Decision ID 118712, Methidathion
Region 5     
Mustang Creek (Merced County)
 
LOE ID: 191287
 
Pollutant: Methidathion
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 2
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed East San Joaquin Water Quality Coalition data for Mustang Creek (Merced County) to determine beneficial use support and results are as follows: 0 of 2 samples exceeded the water quality threshold for Methidathion.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Water Quality Control Plan for the Sacramento and San Joaquin River Basins).
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline: The evaluation guideline for Methidathion is the USEPA Aquatic Life Benchmark of 0.66 ug/L for a invertebrate (acute).
Guideline Reference: OPP Aquatic Life Benchmarks
 
Spatial Representation: The samples were collected at 1 monitoring site (535XMCAEA)
Temporal Representation: The samples were collected between the dates of 2013-01-08 and 2013-02-12
Environmental Conditions:
QAPP Information: Michael L. Johnson LLC. 2015. Quality Assurance Project Plan for Monitoring by the East San Joaquin Water Quality Coalition.
QAPP Information Reference(s): Quality Assurance Project Plan for Monitoring by the East San Joaquin Water Quality Coalition
 
 
DECISION ID
118710
Region 5     
Mustang Creek (Merced County)
 
Pollutant: Methiocarb
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: Do Not List on 303(d) list (TMDL required list)(2018)
Revision Status Revised
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: This pollutant is being considered for placement on the CWA section 303(d) List under section 3.1 of the Listing Policy.

Zero samples exceeded the objectives, guidelines, or criteria for beneficial uses applicable to this water segment-pollutant combination, which is less than the minimum number of exceedances needed to place the water segment on the section CWA section 303(d) List for toxicants (Table 3.1 of the Listing Policy).

The data used satisfies the data quality requirements (section 6.1.4) and data quantity requirements (section 6.1.5) of the Listing Policy.

Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the CWA section 303(d) List.

LOE 68099 has been replaced by LOE 222060 due to a reassessment of data using a U.S. EPA aquatic life benchmark.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because applicable water quality standards are not being exceeded.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.
 
 
Line of Evidence (LOE) for Decision ID 118710, Methiocarb
Region 5     
Mustang Creek (Merced County)
 
LOE ID: 191562
 
Pollutant: Methiocarb
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 2
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed East San Joaquin Water Quality Coalition data for Mustang Creek (Merced County) to determine beneficial use support and results are as follows: 0 of 2 samples exceeded the water quality threshold for Methiocarb.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Water Quality Control Plan for the Sacramento and San Joaquin River Basins).
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline: The evaluation guideline for Methiocarb is the USEPA Aquatic Life Benchmark of 2.75 ug/L for a invertebrate (chronic).
Guideline Reference: OPP Aquatic Life Benchmarks
 
Spatial Representation: The samples were collected at 1 monitoring site (535XMCAEA)
Temporal Representation: The samples were collected between the dates of 2013-01-08 and 2013-02-12
Environmental Conditions:
QAPP Information: Michael L. Johnson LLC. 2015. Quality Assurance Project Plan for Monitoring by the East San Joaquin Water Quality Coalition.
QAPP Information Reference(s): Quality Assurance Project Plan for Monitoring by the East San Joaquin Water Quality Coalition
 
Line of Evidence (LOE) for Decision ID 118710, Methiocarb
Region 5     
Mustang Creek (Merced County)
 
LOE ID: 222060
 
Pollutant: Methiocarb
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 17
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed ILRP_ESJWQC data for Mustang Creek (Merced County) to determine beneficial use support and results are as follows: 0 of 17 samples exceeded the water quality threshold for Methiocarb.
Data Reference: Data for Various Pollutants in East San Joaquin, 2004-2009.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Water Quality Control Plan for the Sacramento and San Joaquin River Basins).
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline: The evaluation guideline for Methiocarb is the USEPA Aquatic Life Benchmark of 2.75 ug/L for a invertebrate (chronic).
Guideline Reference: OPP Aquatic Life Benchmarks
 
Spatial Representation: The samples were collected at 1 monitoring site (535XMCAEA)
Temporal Representation: The samples were collected between the dates of 2006-05-18 and 2010-04-20
Environmental Conditions:
QAPP Information: The Quality Assurance Project Plan by the East San Joaquin Water Quality Coalition, Revision 1.0 was followed.
QAPP Information Reference(s): Quality Assurance Project Plan by the East San Joaquin Water Quality Coalition, Revision 1.0.
 
 
DECISION ID
118711
Region 5     
Mustang Creek (Merced County)
 
Pollutant: Methomyl
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: Do Not List on 303(d) list (TMDL required list)(2018)
Revision Status Revised
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available.
 
Regional Board Decision Recommendation: This decision was made by SWRCB staff.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of the available data and information, SWRCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because it cannot be determined if applicable water quality standards are not being exceeded.
 
 
Line of Evidence (LOE) for Decision ID 118711, Methomyl
Region 5     
Mustang Creek (Merced County)
 
LOE ID: 67969
 
Pollutant: Methomyl
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 14
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Ag Waiver data for Mustang Creek (Merced County) to determine beneficial use support and results are as follows: 0 of 14 samples exceed the criterion for Methomyl.
Data Reference: Data for Various Pollutants in East San Joaquin, 2004-2009.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses. (Water Quality Control Plan, Central Valley Region, Sacramento River Basin and San Joaquin River Basin)
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: The Basin Plan states: "Where valid testing has developed 96-hour LC50 values for aquatic organisms..., the Board will consider one tenth of this value for the most sensitive species tested as the upper limit (daily maximum) for the protection of aquatic life... or [O]ther available information on the pesticide..." The criteria continuous concentration for Methomyl in the San Joaquin River system is 0.5 ug/L (4-day average). (CDFG, 1996)
Guideline Reference: OPP Pesticide Ecotoxicity Database.
 
Spatial Representation: Data for this line of evidence for Mustang Creek (Merced County) was collected at 1 monitoring site [Mustang Creek @ East Ave - 535XMCAEA]
Temporal Representation: Data was collected over the time period 2/12/2007-4/20/2010.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: The Quality Assurance Project Plan by the East San Joaquin Water Quality Coalition, Revision 1.0 was followed.
QAPP Information Reference(s): Quality Assurance Project Plan by the East San Joaquin Water Quality Coalition, Revision 1.0.
 
Line of Evidence (LOE) for Decision ID 118711, Methomyl
Region 5     
Mustang Creek (Merced County)
 
LOE ID: 191480
 
Pollutant: Methomyl
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 2
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed East San Joaquin Water Quality Coalition data for Mustang Creek (Merced County) to determine beneficial use support and results are as follows: 0 of 2 samples exceeded the water quality threshold for Methomyl.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline: The Basin Plan states: \Where valid testing has developed 96-hour LC50 values for aquatic organisms..., the Board will consider one tenth of this value for the most sensitive species tested as the upper limit (daily maximum) for the protection of aquatic life... or [O]ther available information on the pesticide...\" The criteria continuous concentration for Methomyl in the San Joaquin River system is 0.5 ug/L (4-day average). "
Guideline Reference: OPP Pesticide Ecotoxicity Database.
 
Spatial Representation: The samples were collected at 1 monitoring site (535XMCAEA)
Temporal Representation: The samples were collected between the dates of 2013-01-08 and 2013-02-12
Environmental Conditions:
QAPP Information: Michael L. Johnson LLC. 2015. Quality Assurance Project Plan for Monitoring by the East San Joaquin Water Quality Coalition.
QAPP Information Reference(s): Quality Assurance Project Plan for Monitoring by the East San Joaquin Water Quality Coalition
 
 
DECISION ID
118700
Region 5     
Mustang Creek (Merced County)
 
Pollutant: Methyl Parathion
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: Do Not List on 303(d) list (TMDL required list)(2018)
Revision Status Revised
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: This pollutant is being considered for placement on the CWA section 303(d) List under section 3.1 of the Listing Policy. Under section 3.1 a one line(s) of evidence are necessary to assess listing status.

One line of evidence is available in the administrative record to assess this pollutant. Zero of the zero samples exceed the Evaluation Guideline.

Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the CWA section 303(d) List.

This conclusion is based on the staff findings that:
1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy.
2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy.
3. Zero of zero samples exceeded Evaluation Guideline and this sample size is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating. A minimum of 16 samples is needed to determine if a beneficial use is fully supported using table 3.1.
4. Pursuant to Section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.
 
 
Line of Evidence (LOE) for Decision ID 118700, Methyl Parathion
Region 5     
Mustang Creek (Merced County)
 
LOE ID: 67972
 
Pollutant: Methyl Parathion
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 0
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Ag Waiver data for Mustang Creek (Merced County) to determine beneficial use support and results are as follows: 0 of 0 samples exceed the criterion for Parathion, Methyl. Fourteen samples were not used in the assessment because the laboratory data reporting limit(s) was above the objective and therefore the results could not be quantified with the level of certainty required by the Listing Policy.
Data Reference: Data for Various Pollutants in East San Joaquin, 2004-2009.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses. (Water Quality Control Plan, Central Valley Region, Sacramento River Basin and San Joaquin River Basin)
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: The California Department of Fish and Game instantaneous aquatic life criterion for Methyl Parathion is 0.08 ug/L.
Guideline Reference: Hazard Assessment of the Insecticide Methyl Parathion to Aquatic Organisms in the Sacramento River System. California Department of Fish and Game. Environmental Services Division. Administrative Report 92-1
 
Spatial Representation: Data for this line of evidence for Mustang Creek (Merced County) was collected at 1 monitoring site [Mustang Creek @ East Ave - 535XMCAEA]
Temporal Representation: Data was collected over the time period 2/12/2007-4/20/2010.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: The Quality Assurance Project Plan by the East San Joaquin Water Quality Coalition, Revision 1.0 was followed.
QAPP Information Reference(s): Quality Assurance Project Plan by the East San Joaquin Water Quality Coalition, Revision 1.0.
 
Line of Evidence (LOE) for Decision ID 118700, Methyl Parathion
Region 5     
Mustang Creek (Merced County)
 
LOE ID: 192838
 
Pollutant: Methyl Parathion
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 0
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed East San Joaquin Water Quality Coalition data for Mustang Creek (Merced County) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Parathion, Methyl. Although a total of 2 samples were collected, 2 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline: The California Department of Fish and Game instantaneous aquatic life criterion for Methyl Parathion is 0.08 ug/L.
Guideline Reference: Hazard Assessment of the Insecticide Methyl Parathion to Aquatic Organisms in the Sacramento River System. California Department of Fish and Game. Environmental Services Division. Administrative Report 92-1
 
Spatial Representation: The samples were collected at 1 monitoring site (535XMCAEA).
Temporal Representation: Date for this waterbody was collected over the date range 2013-01-08 to 2013-02-12
Environmental Conditions:
QAPP Information: Michael L. Johnson LLC. 2015. Quality Assurance Project Plan for Monitoring by the East San Joaquin Water Quality Coalition.
QAPP Information Reference(s): Quality Assurance Project Plan for Monitoring by the East San Joaquin Water Quality Coalition
 
 
DECISION ID
128787
Region 5     
Mustang Creek (Merced County)
 
Pollutant: Molinate
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: Do Not List on 303(d) list (TMDL required list)(2018)
Revision Status Revised
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available.

LOE 67973 has been replaced by LOE 222395 due to a reassessment of data using a U.S. EPA aquatic life benchmark.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.
 
 
Line of Evidence (LOE) for Decision ID 128787, Molinate
Region 5     
Mustang Creek (Merced County)
 
LOE ID: 222395
 
Pollutant: Molinate
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 9
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed ILRP_ESJWQC data for Mustang Creek (Merced County) to determine beneficial use support and results are as follows: 0 of 9 samples exceeded the water quality threshold for Molinate.
Data Reference: Data for Various Pollutants in East San Joaquin, 2004-2009.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Water Quality Control Plan for the Sacramento and San Joaquin River Basins).
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline: The California Department of Fish and Wildlife hazard assessment instantaneous criterion (1-hour average) for the protection of aquatic life for Molinate is 13 ug/L.
Guideline Reference: Hazard Assessment of the Rice Herbicides Molinate and Thiobencarb to Aquatic Organisms in the Sacramento River System. Administrative Report 90-1. California Department of Fish and Game, Environmental Services Division
 
Spatial Representation: The samples were collected at 1 monitoring site (535XMCAEA)
Temporal Representation: The samples were collected between the dates of 2006-05-18 and 2008-02-26
Environmental Conditions:
QAPP Information: The Quality Assurance Project Plan by the East San Joaquin Water Quality Coalition, Revision 1.0 was followed.
QAPP Information Reference(s): Quality Assurance Project Plan by the East San Joaquin Water Quality Coalition, Revision 1.0.
 
Line of Evidence (LOE) for Decision ID 128787, Molinate
Region 5     
Mustang Creek (Merced County)
 
LOE ID: 67987
 
Pollutant: Molinate
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 6
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Ag Waiver data for Mustang Creek (Merced County) to determine beneficial use support and results are as follows: 0 of 6 samples exceed the criterion for Molinate.
Data Reference: Data for Various Pollutants in East San Joaquin, 2004-2009.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The California primary maximum contaminant level for Molinate is 20 ug/L .
Objective/Criterion Reference: Maximum Contaminant Levels for organic and inorganic chemicals. CCR Title 22
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Data for this line of evidence for Mustang Creek (Merced County) was collected at 1 monitoring site [Mustang Creek @ East Ave - 535XMCAEA]
Temporal Representation: Data was collected over the time period 2/12/2007-2/26/2008.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: The Quality Assurance Project Plan by the East San Joaquin Water Quality Coalition, Revision 1.0 was followed.
QAPP Information Reference(s): Quality Assurance Project Plan by the East San Joaquin Water Quality Coalition, Revision 1.0.
 
 
DECISION ID
118701
Region 5     
Mustang Creek (Merced County)
 
Pollutant: Nickel
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: Do Not List on 303(d) list (TMDL required list)(2018)
Revision Status Revised
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.
 
 
Line of Evidence (LOE) for Decision ID 118701, Nickel
Region 5     
Mustang Creek (Merced County)
 
LOE ID: 67988
 
Pollutant: Nickel
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 8
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Ag Waiver data for Mustang Creek (Merced County) to determine beneficial use support and results are as follows: 0 of 8 samples exceed the criterion for Nickel.
Data Reference: Data for Various Pollutants in East San Joaquin, 2004-2009.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The California primary maximum contaminant level for nickel is 0.1 mg/L.
Objective/Criterion Reference: Maximum Contaminant Levels for organic and inorganic chemicals. CCR Title 22
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Data for this line of evidence for Mustang Creek (Merced County) was collected at 1 monitoring site [Mustang Creek @ East Ave - 535XMCAEA]
Temporal Representation: Data was collected over the time period 2/7/2009-4/20/2010.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: The Quality Assurance Project Plan by the East San Joaquin Water Quality Coalition, Revision 1.0 was followed.
QAPP Information Reference(s): Quality Assurance Project Plan by the East San Joaquin Water Quality Coalition, Revision 1.0.
 
Line of Evidence (LOE) for Decision ID 118701, Nickel
Region 5     
Mustang Creek (Merced County)
 
LOE ID: 191806
 
Pollutant: Nickel
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Commercial or recreational collection of fish, shellfish, or organisms
 
Number of Samples: 2
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed East San Joaquin Water Quality Coalition data for Mustang Creek (Merced County) to determine beneficial use support and results are as follows: 0 of 2 samples exceeded the water quality threshold for Nickel.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The Nickel criteria for the protection of human health from consumption of organisms only is 4,600 ug/L (California Toxics Rule, 2000).
Objective/Criterion Reference: Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (535XMCAEA)
Temporal Representation: The samples were collected between the dates of 2013-01-08 and 2013-02-12
Environmental Conditions:
QAPP Information: Michael L. Johnson LLC. 2015. Quality Assurance Project Plan for Monitoring by the East San Joaquin Water Quality Coalition.
QAPP Information Reference(s): Quality Assurance Project Plan for Monitoring by the East San Joaquin Water Quality Coalition
 
Line of Evidence (LOE) for Decision ID 118701, Nickel
Region 5     
Mustang Creek (Merced County)
 
LOE ID: 191893
 
Pollutant: Nickel
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 2
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed East San Joaquin Water Quality Coalition data for Mustang Creek (Merced County) to determine beneficial use support and results are as follows: 0 of 2 samples exceeded the water quality threshold for Nickel.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The California Primary Maximum Contaminant Level for nickel incorporated by reference in the Water Quality Control Plan for the Sacramento and San Joaquin River Basins is 0.1 mg/L.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (535XMCAEA)
Temporal Representation: The samples were collected between the dates of 2013-01-08 and 2013-02-12
Environmental Conditions:
QAPP Information: Michael L. Johnson LLC. 2015. Quality Assurance Project Plan for Monitoring by the East San Joaquin Water Quality Coalition.
QAPP Information Reference(s): Quality Assurance Project Plan for Monitoring by the East San Joaquin Water Quality Coalition
 
Line of Evidence (LOE) for Decision ID 118701, Nickel
Region 5     
Mustang Creek (Merced County)
 
LOE ID: 191952
 
Pollutant: Nickel
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Commercial or recreational collection of fish, shellfish, or organisms
 
Number of Samples: 2
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed East San Joaquin Water Quality Coalition data for Mustang Creek (Merced County) to determine beneficial use support and results are as follows: 0 of 2 samples exceeded the water quality threshold for Nickel.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The Nickel criteria for the protection of human health from consumption of organisms only is 4,600 ug/L (California Toxics Rule, 2000).
Objective/Criterion Reference: Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (535XMCAEA)
Temporal Representation: The samples were collected between the dates of 2013-01-08 and 2013-02-12
Environmental Conditions:
QAPP Information: Michael L. Johnson LLC. 2015. Quality Assurance Project Plan for Monitoring by the East San Joaquin Water Quality Coalition.
QAPP Information Reference(s): Quality Assurance Project Plan for Monitoring by the East San Joaquin Water Quality Coalition
 
Line of Evidence (LOE) for Decision ID 118701, Nickel
Region 5     
Mustang Creek (Merced County)
 
LOE ID: 191895
 
Pollutant: Nickel
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 2
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed East San Joaquin Water Quality Coalition data for Mustang Creek (Merced County) to determine beneficial use support and results are as follows: 0 of 2 samples exceeded the water quality threshold for Nickel.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: California Toxics Rule (CTR) lists criterion continuous concentrations to protect aquatic life in freshwater. The criterion in freshwater is hardness dependent for each sample and varies based on the ambient hardness during sampling. Section (b)(1) in CTR contains the hardness dependent formula for the metals criterion.
Objective/Criterion Reference: Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (535XMCAEA)
Temporal Representation: The samples were collected between the dates of 2013-01-08 and 2013-02-12
Environmental Conditions:
QAPP Information: Michael L. Johnson LLC. 2015. Quality Assurance Project Plan for Monitoring by the East San Joaquin Water Quality Coalition.
QAPP Information Reference(s): Quality Assurance Project Plan for Monitoring by the East San Joaquin Water Quality Coalition
 
Line of Evidence (LOE) for Decision ID 118701, Nickel
Region 5     
Mustang Creek (Merced County)
 
LOE ID: 191912
 
Pollutant: Nickel
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 2
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed East San Joaquin Water Quality Coalition data for Mustang Creek (Merced County) to determine beneficial use support and results are as follows: 0 of 2 samples exceeded the water quality threshold for Nickel.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The California Primary Maximum Contaminant Level for nickel incorporated by reference in the Water Quality Control Plan for the Sacramento and San Joaquin River Basins is 0.1 mg/L.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (535XMCAEA)
Temporal Representation: The samples were collected between the dates of 2013-01-08 and 2013-02-12
Environmental Conditions:
QAPP Information: Michael L. Johnson LLC. 2015. Quality Assurance Project Plan for Monitoring by the East San Joaquin Water Quality Coalition.
QAPP Information Reference(s): Quality Assurance Project Plan for Monitoring by the East San Joaquin Water Quality Coalition
 
Line of Evidence (LOE) for Decision ID 118701, Nickel
Region 5     
Mustang Creek (Merced County)
 
LOE ID: 67989
 
Pollutant: Nickel
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 8
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed AgWaiver data for Mustang Creek (Merced County) to determine beneficial use support and results are as follows: 0 of 8 samples exceed the criterion for Nickel.
Data Reference: Data for Various Pollutants in East San Joaquin, 2004-2009.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The California Toxics Rule (CTR) lists criterion continuous concentrations (4-day average) to protect aquatic life in freshwater. The chromium criterion in freshwater is hardness-dependent for each sample and varies based on the ambient hardness during sampling. Section (b)(1) in CTR contains the hardness-dependent formula for metals criteria.
Objective/Criterion Reference: Code of Federal Regulations 40 part 131.38 Establishment of numeric criteria for priority toxic pollutants for the State of California. 7/1/2011 Edition
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Data for this line of evidence for Mustang Creek (Merced County) was collected at 1 monitoring site [ Mustang Creek @ East Ave - 535XMCAEA]
Temporal Representation: Data was collected over the time period 2/7/2009-4/20/2010.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: The Quality Assurance Project Plan by the East San Joaquin Water Quality Coalition, Revision 1.0 was followed.
QAPP Information Reference(s): Quality Assurance Project Plan by the East San Joaquin Water Quality Coalition, Revision 1.0.
 
 
DECISION ID
118703
Region 5     
Mustang Creek (Merced County)
 
Pollutant: Oxamyl (Vydate)
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: Do Not List on 303(d) list (TMDL required list)(2018)
Revision Status Revised
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: This pollutant is being considered for placement on the CWA section 303(d) List under section 3.1 of the Listing Policy. Under section 3.1 a one line(s) of evidence are necessary to assess listing status.

Three lines of evidence are available in the administrative record to assess this pollutant.
Zero of 14 and 0 of 2 samples exceed the guideline for the Municipal and Domestic Supply beneficial use.
Zero of 2 samples exceed the Cold Freshwater Habitat beneficial use.

Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the CWA section 303(d) List.

This conclusion is based on the staff findings that:
1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy.
2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy.
3. Zero of the samples exceed the guidelines for the Municipal and Domestic Supply and Warm Freshwater Habitat beneficial uses with the statistical power and confidence required by the Listing Policy..
4. Pursuant to Section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
 
Regional Board Decision Recommendation: This decision was made by SWRCB staff.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of the available data and information, SWRCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because the evaluation guideline for the Municipal and Domestic Supply beneficial use was not exceeded.

Insufficient information is available to determine Cold Freshwater Habitat beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy.
 
 
Line of Evidence (LOE) for Decision ID 118703, Oxamyl (Vydate)
Region 5     
Mustang Creek (Merced County)
 
LOE ID: 192687
 
Pollutant: Oxamyl (Vydate)
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 2
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed East San Joaquin Water Quality Coalition data for Mustang Creek (Merced County) to determine beneficial use support and results are as follows: 0 of 2 samples exceeded the water quality threshold for Oxamyl.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The California Primary Maximum Contaminant Level for Oxamyl incorporated by reference in the Water Quality Control Plan for the Sacramento and San Joaquin River Basins is 0.05 mg/L
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (535XMCAEA)
Temporal Representation: The samples were collected between the dates of 2013-01-08 and 2013-02-12
Environmental Conditions:
QAPP Information: Michael L. Johnson LLC. 2015. Quality Assurance Project Plan for Monitoring by the East San Joaquin Water Quality Coalition.
QAPP Information Reference(s): Quality Assurance Project Plan for Monitoring by the East San Joaquin Water Quality Coalition
 
Line of Evidence (LOE) for Decision ID 118703, Oxamyl (Vydate)
Region 5     
Mustang Creek (Merced County)
 
LOE ID: 192714
 
Pollutant: Oxamyl (Vydate)
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 2
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed East San Joaquin Water Quality Coalition data for Mustang Creek (Merced County) to determine beneficial use support and results are as follows: 0 of 2 samples exceeded the water quality threshold for Oxamyl.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline: The evaluation guideline for oxamyl is the USEPA Aquatic Life Benchmark of 27 ug/L for chronic toxicity in invertebrates (7 day average).
Guideline Reference: OPP Aquatic Life Benchmarks
 
Spatial Representation: The samples were collected at 1 monitoring site (535XMCAEA)
Temporal Representation: The samples were collected between the dates of 2013-01-08 and 2013-02-12
Environmental Conditions:
QAPP Information: Michael L. Johnson LLC. 2015. Quality Assurance Project Plan for Monitoring by the East San Joaquin Water Quality Coalition.
QAPP Information Reference(s): Quality Assurance Project Plan for Monitoring by the East San Joaquin Water Quality Coalition
 
Line of Evidence (LOE) for Decision ID 118703, Oxamyl (Vydate)
Region 5     
Mustang Creek (Merced County)
 
LOE ID: 79643
 
Pollutant: Oxamyl (Vydate)
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 14
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: State Water Board staff assessed ILRP data for Mustang Creek (Merced County) to determine beneficial use support and results are as follows: 0 of 14 samples exceed the criterion for Oxamyl.
Data Reference: Data for Various Pollutants in East San Joaquin, 2004-2009.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The California Maximum Contaminant Level for Oxamyl incorporated by reference in the Water Quality Control Plan, Central Valley Region, Sacramento and San Joaquin Basins is 50 ug/L (Water Quality Control Plan, Central Valley Region, Sacramento and San Joaquin Basins).
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Data for this line of evidence for Mustang Creek (Merced County) was collected at 1 monitoring site [ Mustang Creek @ East Ave - 535XMCAEA]
Temporal Representation: Data was collected over the time period 2/12/2007-4/20/2010.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: The Quality Assurance Project Plan by the East San Joaquin Water Quality Coalition, Revision 1.0 was followed.
QAPP Information Reference(s):
 
 
DECISION ID
128788
Region 5     
Mustang Creek (Merced County)
 
Pollutant: Paraquat
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: Do Not List on 303(d) list (TMDL required list)(2018)
Revision Status Revised
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: Previously considered water quality data was reevaluated according to new guidelines as part of this assessment. Line of evidence #68000 was replaced by #222377.

Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.
 
 
Line of Evidence (LOE) for Decision ID 128788, Paraquat
Region 5     
Mustang Creek (Merced County)
 
LOE ID: 222377
 
Pollutant: Paraquat
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 0
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed ILRP_ESJWQC data for Mustang Creek (Merced County) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Paraquat. Although a total of 12 samples were collected, 12 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference: Data for Various Pollutants in East San Joaquin, 2004-2009.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Water Quality Control Plan for the Sacramento and San Joaquin River Basins).
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline: The evaluation guideline for Paraquat is the USEPA Aquatic Life Benchmark of 0.396 ug/L for a nonvascular plant (acute) for Paraquat dichloride.
Guideline Reference: OPP Aquatic Life Benchmarks
 
Spatial Representation: The samples were collected at 1 monitoring site (535XMCAEA).
Temporal Representation: Date for this waterbody was collected over the date range 2006-05-18 to 2009-12-15
Environmental Conditions:
QAPP Information: The Quality Assurance Project Plan by the East San Joaquin Water Quality Coalition, Revision 1.0 was followed.
QAPP Information Reference(s): Quality Assurance Project Plan by the East San Joaquin Water Quality Coalition, Revision 1.0.
 
 
DECISION ID
130395
Region 5     
Mustang Creek (Merced County)
 
Pollutant: Permethrin
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: Do Not List on 303(d) list (TMDL required list)(2018)
Revision Status Revised
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: Previously assessed data was re-evaluated according to new guidelines. Line of evidence #68001 was replaced by #215033.

Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of the available data and information, SWRCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because it cannot be determined if applicable water quality standards are not being exceeded.
 
 
Line of Evidence (LOE) for Decision ID 130395, Permethrin
Region 5     
Mustang Creek (Merced County)
 
LOE ID: 215033
 
Pollutant: Permethrin
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 0
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Ag Waiver data for Mustang Creek (Merced County) to determine beneficial use support and results are as follows: 0 of 0 samples exceed the criterion for Permethrin, Total. Six samples were not used in the assessment because the laboratory data reporting limit(s) was above the objective and therefore the results could not be quantified with the level of certainty required by the Listing Policy.
Data Reference: Data for Various Pollutants in East San Joaquin, 2004-2009.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline: The chronic concentration goal for Permethrin is 1 ng/L (expressed as a 4-day average).  If the freely dissolved concentrations of Permethrin were reported or could be calculated then these values were used for this assessment.  In the absence of freely dissolved concentrations, total concentrations were used.
Guideline Reference: Water Quality Criteria Report for Permethrin
Guideline Reference: Amendment to the Water Quality Control Plan for the Sacramento River and San Joaquin River Basins for the Control of Pyrethroid Pesticide Discharges
 
Spatial Representation: Data for this line of evidence for Mustang Creek (Merced County) was collected at 1 monitoring site [Mustang Creek @ East Ave - 535XMCAEA]
Temporal Representation: Data was collected over the time period 2/12/2007-2/26/2008.
Environmental Conditions:
QAPP Information: The Quality Assurance Project Plan by the East San Joaquin Water Quality Coalition, Revision 1.0 was followed.
QAPP Information Reference(s): Quality Assurance Project Plan by the East San Joaquin Water Quality Coalition, Revision 1.0.
 
Line of Evidence (LOE) for Decision ID 130395, Permethrin
Region 5     
Mustang Creek (Merced County)
 
LOE ID: 192916
 
Pollutant: Permethrin
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 0
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed East San Joaquin Water Quality Coalition data for Mustang Creek (Merced County) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Permethrin. Although a total of 2 samples were collected, 2 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline: The chronic concentration goal for Permethrin is 1 ng/L (expressed as a 4-day average).  If the freely dissolved concentrations of Permethrin were reported or could be calculated then these values were used for this assessment.  In the absence of freely dissolved concentrations, total concentrations were used.
Guideline Reference: Water Quality Criteria Report for Permethrin
Guideline Reference: Amendment to the Water Quality Control Plan for the Sacramento River and San Joaquin River Basins for the Control of Pyrethroid Pesticide Discharges
 
Spatial Representation: The samples were collected at 1 monitoring site (535XMCAEA).
Temporal Representation: Date for this waterbody was collected over the date range 2013-01-08 to 2013-02-12
Environmental Conditions:
QAPP Information: Michael L. Johnson LLC. 2015. Quality Assurance Project Plan for Monitoring by the East San Joaquin Water Quality Coalition.
QAPP Information Reference(s): Quality Assurance Project Plan for Monitoring by the East San Joaquin Water Quality Coalition
 
 
DECISION ID
118715
Region 5     
Mustang Creek (Merced County)
 
Pollutant: Phorate
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: Do Not List on 303(d) list (TMDL required list)(2018)
Revision Status Revised
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: This pollutant is being considered for placement on the CWA section 303(d) List under section 3.1 of the Listing Policy.

Zero samples exceeded the objectives, guidelines, or criteria for beneficial uses applicable to this water segment-pollutant combination, which is less than the minimum number of exceedances needed to place the water segment on the section CWA section 303(d) List for toxicants (Table 3.1 of the Listing Policy).

The data used satisfies the data quality requirements (section 6.1.4) and data quantity requirements (section 6.1.5) of the Listing Policy.

Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the CWA section 303(d) List.

LOE 68002 has been replaced by LOE 222347 due to a reassessment of data using a U.S. EPA aquatic life benchmark.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because applicable water quality standards are not being exceeded.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.
 
 
Line of Evidence (LOE) for Decision ID 118715, Phorate
Region 5     
Mustang Creek (Merced County)
 
LOE ID: 192999
 
Pollutant: Phorate
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 2
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed East San Joaquin Water Quality Coalition data for Mustang Creek (Merced County) to determine beneficial use support and results are as follows: 0 of 2 samples exceeded the water quality threshold for Phorate.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Water Quality Control Plan for the Sacramento and San Joaquin River Basins).
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline: The evaluation guideline for Phorate is the USEPA Aquatic Life Benchmark of 0.21 ug/L for a invertebrate (acute).
Guideline Reference: OPP Aquatic Life Benchmarks
 
Spatial Representation: The samples were collected at 1 monitoring site (535XMCAEA)
Temporal Representation: The samples were collected between the dates of 2013-01-08 and 2013-02-12
Environmental Conditions:
QAPP Information: Michael L. Johnson LLC. 2015. Quality Assurance Project Plan for Monitoring by the East San Joaquin Water Quality Coalition.
QAPP Information Reference(s): Quality Assurance Project Plan for Monitoring by the East San Joaquin Water Quality Coalition
 
Line of Evidence (LOE) for Decision ID 118715, Phorate
Region 5     
Mustang Creek (Merced County)
 
LOE ID: 222347
 
Pollutant: Phorate
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 17
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed ILRP_ESJWQC data for Mustang Creek (Merced County) to determine beneficial use support and results are as follows: 0 of 17 samples exceeded the water quality threshold for Phorate.
Data Reference: Data for Various Pollutants in East San Joaquin, 2004-2009.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Water Quality Control Plan for the Sacramento and San Joaquin River Basins).
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline: The evaluation guideline for Phorate is the USEPA Aquatic Life Benchmark of 0.21 ug/L for a invertebrate (acute).
Guideline Reference: OPP Aquatic Life Benchmarks
 
Spatial Representation: The samples were collected at 1 monitoring site (535XMCAEA)
Temporal Representation: The samples were collected between the dates of 2006-05-18 and 2010-04-20
Environmental Conditions:
QAPP Information: The Quality Assurance Project Plan by the East San Joaquin Water Quality Coalition, Revision 1.0 was followed.
QAPP Information Reference(s): Quality Assurance Project Plan by the East San Joaquin Water Quality Coalition, Revision 1.0.
 
 
DECISION ID
118717
Region 5     
Mustang Creek (Merced County)
 
Pollutant: Phosmet
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: Do Not List on 303(d) list (TMDL required list)(2018)
Revision Status Revised
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.

LOE 68003 has been replaced by LOE 222316 due to a reassessment of data using a U.S. EPA aquatic life benchmark.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.
 
 
Line of Evidence (LOE) for Decision ID 118717, Phosmet
Region 5     
Mustang Creek (Merced County)
 
LOE ID: 193278
 
Pollutant: Phosmet
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 2
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed East San Joaquin Water Quality Coalition data for Mustang Creek (Merced County) to determine beneficial use support and results are as follows: 0 of 2 samples exceeded the water quality threshold for Phosmet.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Water Quality Control Plan for the Sacramento and San Joaquin River Basins).
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline: The evaluation guideline for Phosmet is the USEPA Aquatic Life Benchmark of 0.8 ug/L for a invertebrate (acute).
Guideline Reference: OPP Aquatic Life Benchmarks
 
Spatial Representation: The samples were collected at 1 monitoring site (535XMCAEA)
Temporal Representation: The samples were collected between the dates of 2013-01-08 and 2013-02-12
Environmental Conditions:
QAPP Information: Michael L. Johnson LLC. 2015. Quality Assurance Project Plan for Monitoring by the East San Joaquin Water Quality Coalition.
QAPP Information Reference(s): Quality Assurance Project Plan for Monitoring by the East San Joaquin Water Quality Coalition
 
Line of Evidence (LOE) for Decision ID 118717, Phosmet
Region 5     
Mustang Creek (Merced County)
 
LOE ID: 222316
 
Pollutant: Phosmet
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 17
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed ILRP_ESJWQC data for Mustang Creek (Merced County) to determine beneficial use support and results are as follows: 0 of 17 samples exceeded the water quality threshold for Phosmet.
Data Reference: Data for Various Pollutants in East San Joaquin, 2004-2009.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Water Quality Control Plan for the Sacramento and San Joaquin River Basins).
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline: The evaluation guideline for Phosmet is the USEPA Aquatic Life Benchmark of 0.8 ug/L for a invertebrate (acute).
Guideline Reference: OPP Aquatic Life Benchmarks
 
Spatial Representation: The samples were collected at 1 monitoring site (535XMCAEA)
Temporal Representation: The samples were collected between the dates of 2006-05-18 and 2010-04-20
Environmental Conditions:
QAPP Information: The Quality Assurance Project Plan by the East San Joaquin Water Quality Coalition, Revision 1.0 was followed.
QAPP Information Reference(s): Quality Assurance Project Plan by the East San Joaquin Water Quality Coalition, Revision 1.0.
 
 
DECISION ID
118709
Region 5     
Mustang Creek (Merced County)
 
Pollutant: Pyrethroids
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: New Decision
Revision Status Revised
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of the available data and information, SWRCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because it cannot be determined if applicable water quality standards are not being exceeded.
 
 
Line of Evidence (LOE) for Decision ID 118709, Pyrethroids
Region 5     
Mustang Creek (Merced County)
 
LOE ID: 193103
 
Pollutant: Pyrethroids
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 0
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed East San Joaquin Water Quality Coalition data for Mustang Creek (Merced County) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Pyrethroids. Although a total of 2 samples were collected, 2 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline: The summed ratios of the pyrethroid pesticides bifenthrin, cyfluthrin, cypermethrin, esfenvalerate, lambda-cyhalothrin, permethrin and their respective chronic concentration goals are not to exceed 1. If the freely dissolved concentrations of these pesticides were reported or could be calculated then these values were used for this assessment.  In the absence of freely dissolved concentrations, total concentrations were used.
Guideline Reference: Amendment to the Water Quality Control Plan for the Sacramento River and San Joaquin River Basins for the Control of Pyrethroid Pesticide Discharges
 
Spatial Representation: The samples were collected at 1 monitoring site (535XMCAEA).
Temporal Representation: Date for this waterbody was collected over the date range 2013-01-08 to 2013-02-12
Environmental Conditions:
QAPP Information: Michael L. Johnson LLC. 2015. Quality Assurance Project Plan for Monitoring by the East San Joaquin Water Quality Coalition.
QAPP Information Reference(s): Quality Assurance Project Plan for Monitoring by the East San Joaquin Water Quality Coalition
 
 
DECISION ID
118704
Region 5     
Mustang Creek (Merced County)
 
Pollutant: Selenium
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: Do Not List on 303(d) list (TMDL required list)(2018)
Revision Status Revised
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.
 
 
Line of Evidence (LOE) for Decision ID 118704, Selenium
Region 5     
Mustang Creek (Merced County)
 
LOE ID: 68009
 
Pollutant: Selenium
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 8
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Ag Waiver data for Mustang Creek (Merced County) to determine beneficial use support and results are as follows: 0 of 8 samples exceed the criterion for Selenium.
Data Reference: Data for Various Pollutants in East San Joaquin, 2004-2009.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The California primary maximum contaminant level for selenium is 0.05 mg/L.
Objective/Criterion Reference: Maximum Contaminant Levels for organic and inorganic chemicals. CCR Title 22
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Data for this line of evidence for Mustang Creek (Merced County) was collected at 1 monitoring site [Mustang Creek @ East Ave - 535XMCAEA]
Temporal Representation: Data was collected over the time period 2/7/2009-4/20/2010.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: The Quality Assurance Project Plan by the East San Joaquin Water Quality Coalition, Revision 1.0 was followed.
QAPP Information Reference(s): Quality Assurance Project Plan by the East San Joaquin Water Quality Coalition, Revision 1.0.
 
Line of Evidence (LOE) for Decision ID 118704, Selenium
Region 5     
Mustang Creek (Merced County)
 
LOE ID: 193271
 
Pollutant: Selenium
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 2
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed East San Joaquin Water Quality Coalition data for Mustang Creek (Merced County) to determine beneficial use support and results are as follows: 0 of 2 samples exceeded the water quality threshold for Selenium.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The California Primary Maximum Contaminant Level for selenium incorporated by reference in the Water Quality Control Plan for the Sacramento and San Joaquin River Basins is 0.05 mg/L.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (535XMCAEA)
Temporal Representation: The samples were collected between the dates of 2013-01-08 and 2013-02-12
Environmental Conditions:
QAPP Information: Michael L. Johnson LLC. 2015. Quality Assurance Project Plan for Monitoring by the East San Joaquin Water Quality Coalition.
QAPP Information Reference(s): Quality Assurance Project Plan for Monitoring by the East San Joaquin Water Quality Coalition
 
Line of Evidence (LOE) for Decision ID 118704, Selenium
Region 5     
Mustang Creek (Merced County)
 
LOE ID: 193394
 
Pollutant: Selenium
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 2
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed East San Joaquin Water Quality Coalition data for Mustang Creek (Merced County) to determine beneficial use support and results are as follows: 0 of 2 samples exceeded the water quality threshold for Selenium.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The selenium criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in freshwater is 5 ug/L (California Toxics Rule, 2000).
Objective/Criterion Reference: Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (535XMCAEA)
Temporal Representation: The samples were collected between the dates of 2013-01-08 and 2013-02-12
Environmental Conditions:
QAPP Information: Michael L. Johnson LLC. 2015. Quality Assurance Project Plan for Monitoring by the East San Joaquin Water Quality Coalition.
QAPP Information Reference(s): Quality Assurance Project Plan for Monitoring by the East San Joaquin Water Quality Coalition
 
Line of Evidence (LOE) for Decision ID 118704, Selenium
Region 5     
Mustang Creek (Merced County)
 
LOE ID: 68010
 
Pollutant: Selenium
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 8
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Ag Waiver data for Mustang Creek (Merced County) to determine beneficial use support and results are as follows: 0 of 8 samples exceed the criterion for Selenium.
Data Reference: Data for Various Pollutants in East San Joaquin, 2004-2009.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The selenium criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in freshwater is 0.005 mg/L (California Toxics Rule, 2000).
Objective/Criterion Reference: Code of Federal Regulations 40 part 131.38 Establishment of numeric criteria for priority toxic pollutants for the State of California. 7/1/2011 Edition
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Data for this line of evidence for Mustang Creek (Merced County) was collected at 1 monitoring site [Mustang Creek @ East Ave - 535XMCAEA]
Temporal Representation: Data was collected over the time period 2/7/2009-4/20/2010.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: The Quality Assurance Project Plan by the East San Joaquin Water Quality Coalition, Revision 1.0 was followed.
QAPP Information Reference(s): Quality Assurance Project Plan by the East San Joaquin Water Quality Coalition, Revision 1.0.
 
 
DECISION ID
129484
Region 5     
Mustang Creek (Merced County)
 
Pollutant: Specific Conductivity
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: Do Not List on 303(d) list (TMDL required list)(2018)
Revision Status Revised
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available.
 
Regional Board Decision Recommendation: This decision was made by SWRCB staff.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of the available data and information, SWRCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because it cannot be determined if applicable water quality standards are not being exceeded.
 
 
Line of Evidence (LOE) for Decision ID 129484, Specific Conductivity
Region 5     
Mustang Creek (Merced County)
 
LOE ID: 229971
 
Pollutant: Specific Conductivity
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 16
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed East San Joaquin Water Quality Coalition data for Mustang Creek (Merced County) to determine beneficial use support and results are as follows: 0 of 16 samples exceeded the water quality threshold for SpecificConductivity.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The California Secondary MCL that is incorporated by reference in the Water Quality Control Plan, Central Valley Region Sacramento River Basin and San Joaquin River Basin for specific conductance is 900 uS/cm.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (535XMCAEA)
Temporal Representation: The samples were collected between the dates of 2013-01-08 and 2016-12-09
Environmental Conditions:
QAPP Information: Michael L. Johnson LLC. 2015. Quality Assurance Project Plan for Monitoring by the East San Joaquin Water Quality Coalition.
QAPP Information Reference(s): Quality Assurance Project Plan for Monitoring by the East San Joaquin Water Quality Coalition
 
Line of Evidence (LOE) for Decision ID 129484, Specific Conductivity
Region 5     
Mustang Creek (Merced County)
 
LOE ID: 68079
 
Pollutant: Specific Conductivity
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 21
Number of Exceedances: 3
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Ag Waiver data for Mustang Creek (Merced County) to determine beneficial use support and results are as follows: 3 of 21 samples exceed the criterion for Conductivity(Us).
Data Reference: Data for Various Pollutants in East San Joaquin, 2004-2009.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The California secondary maximum contaminant levels for electrical conductivity provide a range of values including a recommended level (900 uS/cm), an upper level (1,600 uS/cm) and a short-term level (2,200 uS/cm). The recommended level of 900 uS/cm was used as it is protective of all drinking water uses.
Objective/Criterion Reference: Secondary Maximum Contaminant Levels and Compliance. CCR Title 22 section 64449.
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Data for this line of evidence for Mustang Creek (Merced County) was collected at 1 monitoring site [Mustang Creek @ East Ave - 535XMCAEA]
Temporal Representation: Data was collected over the time period 2/12/2007-7/20/2010.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: The Quality Assurance Project Plan by the East San Joaquin Water Quality Coalition, Revision 1.0 was followed.
QAPP Information Reference(s): Quality Assurance Project Plan by the East San Joaquin Water Quality Coalition, Revision 1.0.
 
 
DECISION ID
122995
Region 5     
Mustang Creek (Merced County)
 
Pollutant: Temperature, water
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: Do Not List on 303(d) list (TMDL required list)(2018)
Revision Status Revised
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: This pollutant is being considered for placement on the CWA section 303(d) List under section 3.2 of the Listing Policy. Under section 3.2 a single line of evidence is necessary to assess listing status.

4 lines of evidence are available in the administrative record to assess this pollutant. 3 of the 36 samples exceed the OBJECTIVE for COLD. 0 of the 16 samples exceed the OBJECTIVE for Fish Migration and Fish Spawning.

Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the CWA section 303(d) List.

This conclusion is based on the staff findings that:
1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy.
2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy.
3. 3 of the 36 samples exceeded the OBJECTIVE for COLD. 0 of the 16 samples exceeded the OBJECTIVE for Fish Migration and Fish Spawning. This does not exceed the allowable frequency listed in Table 3.2 of the Listing Policy.
4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
 
Regional Board Decision Recommendation: This decision was made by SWRCB staff.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of the available data and information, SWRCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because applicable water quality standards for the pollutant are not exceeded.
 
 
Line of Evidence (LOE) for Decision ID 122995, Temperature, water
Region 5     
Mustang Creek (Merced County)
 
LOE ID: 230332
 
Pollutant: Temperature, water
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Not Recorded
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 16
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed East San Joaquin Water Quality Coalition data for Mustang Creek (Merced County) to determine beneficial use support and results are as follows: 0 of 16 samples exceeded the water quality threshold for Temperature.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The natural receiving water temperature of intrastate waters shall not be altered unless it can be demonstrated to the satisfaction of the Regional Water Board that such alteration in temperature does not adversely affect beneficial uses (Sacramento-San Joaquin River Basin Plans.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline: Inland Fishes of California (Moyle 1976) states that for rainbow trout the optimum range for growth and completion of most life stages is 13-21 degrees C (page 129).
Guideline Reference: Inland Fishes of California
 
Spatial Representation: The samples were collected at 1 monitoring site (535XMCAEA)
Temporal Representation: The samples were collected between the dates of 2013-01-08 and 2016-12-09
Environmental Conditions:
QAPP Information: Michael L. Johnson LLC. 2015. Quality Assurance Project Plan for Monitoring by the East San Joaquin Water Quality Coalition.
QAPP Information Reference(s): Quality Assurance Project Plan for Monitoring by the East San Joaquin Water Quality Coalition
 
Line of Evidence (LOE) for Decision ID 122995, Temperature, water
Region 5     
Mustang Creek (Merced County)
 
LOE ID: 230293
 
Pollutant: Temperature, water
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Not Recorded
 
Beneficial Use: Fish Migration
 
Number of Samples: 16
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed East San Joaquin Water Quality Coalition data for Mustang Creek (Merced County) to determine beneficial use support and results are as follows: 0 of 16 samples exceeded the water quality threshold for Temperature.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The natural receiving water temperature of intrastate waters shall not be altered unless it can be demonstrated to the satisfaction of the Regional Water Board that such alteration in temperature does not adversely affect beneficial uses (Sacramento-San Joaquin River Basin Plans.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline: Inland Fishes of California (Moyle 1976) states that for rainbow trout the optimum range for growth and completion of most life stages is 13-21 degrees C (page 129).
Guideline Reference: Inland Fishes of California
 
Spatial Representation: The samples were collected at 1 monitoring site (535XMCAEA)
Temporal Representation: The samples were collected between the dates of 2013-01-08 and 2016-12-09
Environmental Conditions:
QAPP Information: Michael L. Johnson LLC. 2015. Quality Assurance Project Plan for Monitoring by the East San Joaquin Water Quality Coalition.
QAPP Information Reference(s): Quality Assurance Project Plan for Monitoring by the East San Joaquin Water Quality Coalition
 
Line of Evidence (LOE) for Decision ID 122995, Temperature, water
Region 5     
Mustang Creek (Merced County)
 
LOE ID: 68013
 
Pollutant: Temperature, water
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 20
Number of Exceedances: 3
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Ag Waiver data for Mustang Creek (Merced County) to determine beneficial use support and results are as follows: 3 of 20 samples exceed the criterion for Water Temperature.
Data Reference: Data for Various Pollutants in East San Joaquin, 2004-2009.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The natural receiving water temperature of intrastate waters shall not be altered unless it can be demonstrated to the satisfaction of the Regional Water Board that such alteration in temperature does not adversely affect beneficial uses (Sacramento-San Juoaquin River Basin Plans).
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: Inland Fishes of California (Moyle 1976) states that for rainbow trout the optimum range for growth and completion of most life stages is 13-21 degrees C (page 129).
Guideline Reference: Inland Fishes of California (1976)
 
Spatial Representation: Data for this line of evidence for Mustang Creek (Merced County) was collected at 1 monitoring site [Mustang Creek @ East Ave - 535XMCAEA]
Temporal Representation: Data was collected over the time period 2/12/2007-7/20/2010.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: The Quality Assurance Project Plan by the East San Joaquin Water Quality Coalition, Revision 1.0 was followed.
QAPP Information Reference(s): Quality Assurance Project Plan by the East San Joaquin Water Quality Coalition, Revision 1.0.
 
Line of Evidence (LOE) for Decision ID 122995, Temperature, water
Region 5     
Mustang Creek (Merced County)
 
LOE ID: 230603
 
Pollutant: Temperature, water
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Not Recorded
 
Beneficial Use: Fish Spawning
 
Number of Samples: 16
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed East San Joaquin Water Quality Coalition data for Mustang Creek (Merced County) to determine beneficial use support and results are as follows: 0 of 16 samples exceeded the water quality threshold for Temperature.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The natural receiving water temperature of intrastate waters shall not be altered unless it can be demonstrated to the satisfaction of the Regional Water Board that such alteration in temperature does not adversely affect beneficial uses (Sacramento-San Joaquin River Basin Plans.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline: Inland Fishes of California (Moyle 1976) states that for rainbow trout the optimum range for growth and completion of most life stages is 13-21 degrees C (page 129).
Guideline Reference: Inland Fishes of California
 
Spatial Representation: The samples were collected at 1 monitoring site (535XMCAEA)
Temporal Representation: The samples were collected between the dates of 2013-01-08 and 2016-12-09
Environmental Conditions:
QAPP Information: Michael L. Johnson LLC. 2015. Quality Assurance Project Plan for Monitoring by the East San Joaquin Water Quality Coalition.
QAPP Information Reference(s): Quality Assurance Project Plan for Monitoring by the East San Joaquin Water Quality Coalition
 
 
DECISION ID
128789
Region 5     
Mustang Creek (Merced County)
 
Pollutant: Thiobencarb
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: New Decision
Revision Status Revised
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation:
 
 
Line of Evidence (LOE) for Decision ID 128789, Thiobencarb
Region 5     
Mustang Creek (Merced County)
 
LOE ID: 222578
 
Pollutant: Thiobencarb
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 9
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed ILRP_ESJWQC data for Mustang Creek (Merced County) to determine beneficial use support and results are as follows: 0 of 9 samples exceeded the water quality threshold for Thiobencarb.
Data Reference: Data for Various Pollutants in East San Joaquin, 2004-2009.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Water Quality Control Plan for the Sacramento and San Joaquin River Basins).
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline: The evaluation guideline for Thiobencarb is the USEPA Aquatic Life Benchmark of 1 ug/L for a invertebrate (acute).
Guideline Reference: OPP Aquatic Life Benchmarks
 
Spatial Representation: The samples were collected at 1 monitoring site (535XMCAEA)
Temporal Representation: The samples were collected between the dates of 2006-05-18 and 2008-02-26
Environmental Conditions:
QAPP Information: The Quality Assurance Project Plan by the East San Joaquin Water Quality Coalition, Revision 1.0 was followed.
QAPP Information Reference(s): Quality Assurance Project Plan by the East San Joaquin Water Quality Coalition, Revision 1.0.
 
 
DECISION ID
118707
Region 5     
Mustang Creek (Merced County)
 
Pollutant: Trifluralin
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: Do Not List on 303(d) list (TMDL required list)(2018)
Revision Status Revised
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available.

LOE 68022 has been replaced by LOE 222513 due to a reassessment of data using a U.S. EPA aquatic life benchmark.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because applicable water quality standards are not being exceeded.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.
 
 
Line of Evidence (LOE) for Decision ID 118707, Trifluralin
Region 5     
Mustang Creek (Merced County)
 
LOE ID: 194254
 
Pollutant: Trifluralin
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 2
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed East San Joaquin Water Quality Coalition data for Mustang Creek (Merced County) to determine beneficial use support and results are as follows: 0 of 2 samples exceeded the water quality threshold for Trifluralin.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Water Quality Control Plan for the Sacramento and San Joaquin River Basins).
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline: The evaluation guideline for Trifluralin is the USEPA Aquatic Life Benchmark of 1.9 ug/L for a fish (chronic).
Guideline Reference: OPP Aquatic Life Benchmarks
 
Spatial Representation: The samples were collected at 1 monitoring site (535XMCAEA)
Temporal Representation: The samples were collected between the dates of 2013-01-08 and 2013-02-12
Environmental Conditions:
QAPP Information: Michael L. Johnson LLC. 2015. Quality Assurance Project Plan for Monitoring by the East San Joaquin Water Quality Coalition.
QAPP Information Reference(s): Quality Assurance Project Plan for Monitoring by the East San Joaquin Water Quality Coalition
 
Line of Evidence (LOE) for Decision ID 118707, Trifluralin
Region 5     
Mustang Creek (Merced County)
 
LOE ID: 222513
 
Pollutant: Trifluralin
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 8
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed ILRP_ESJWQC data for Mustang Creek (Merced County) to determine beneficial use support and results are as follows: 0 of 8 samples exceeded the water quality threshold for Trifluralin.
Data Reference: Data for Various Pollutants in East San Joaquin, 2004-2009.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Water Quality Control Plan for the Sacramento and San Joaquin River Basins).
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline: The evaluation guideline for Trifluralin is the USEPA Aquatic Life Benchmark of 1.9 ug/L for a fish (chronic).
Guideline Reference: OPP Aquatic Life Benchmarks
 
Spatial Representation: The samples were collected at 1 monitoring site (535XMCAEA)
Temporal Representation: The samples were collected between the dates of 2009-02-07 and 2010-04-20
Environmental Conditions:
QAPP Information: The Quality Assurance Project Plan by the East San Joaquin Water Quality Coalition, Revision 1.0 was followed.
QAPP Information Reference(s): Quality Assurance Project Plan by the East San Joaquin Water Quality Coalition, Revision 1.0.
 
 
DECISION ID
118708
Region 5     
Mustang Creek (Merced County)
 
Pollutant: Zinc
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: Do Not List on 303(d) list (TMDL required list)(2018)
Revision Status Revised
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.
 
 
Line of Evidence (LOE) for Decision ID 118708, Zinc
Region 5     
Mustang Creek (Merced County)
 
LOE ID: 194382
 
Pollutant: Zinc
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 2
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed East San Joaquin Water Quality Coalition data for Mustang Creek (Merced County) to determine beneficial use support and results are as follows: 0 of 2 samples exceeded the water quality threshold for Zinc.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: California Toxics Rule (CTR) lists criterion continuous concentrations to protect aquatic life in freshwater. The criterion in freshwater is hardness dependent for each sample and varies based on the ambient hardness during sampling. Section (b)(1) in CTR contains the hardness dependent formula for the metals criterion.
Objective/Criterion Reference: Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (535XMCAEA)
Temporal Representation: The samples were collected between the dates of 2013-01-08 and 2013-02-12
Environmental Conditions:
QAPP Information: Michael L. Johnson LLC. 2015. Quality Assurance Project Plan for Monitoring by the East San Joaquin Water Quality Coalition.
QAPP Information Reference(s): Quality Assurance Project Plan for Monitoring by the East San Joaquin Water Quality Coalition
 
Line of Evidence (LOE) for Decision ID 118708, Zinc
Region 5     
Mustang Creek (Merced County)
 
LOE ID: 194358
 
Pollutant: Zinc
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 2
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed East San Joaquin Water Quality Coalition data for Mustang Creek (Merced County) to determine beneficial use support and results are as follows: 0 of 2 samples exceeded the water quality threshold for Zinc.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The California Secondary Maximum Contaminant Level for zinc incorporated by reference in the Water Quality Control Plan for the Sacramento and San Joaquin River Basins is 5.0 mg/L.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (535XMCAEA)
Temporal Representation: The samples were collected between the dates of 2013-01-08 and 2013-02-12
Environmental Conditions:
QAPP Information: Michael L. Johnson LLC. 2015. Quality Assurance Project Plan for Monitoring by the East San Joaquin Water Quality Coalition.
QAPP Information Reference(s): Quality Assurance Project Plan for Monitoring by the East San Joaquin Water Quality Coalition
 
Line of Evidence (LOE) for Decision ID 118708, Zinc
Region 5     
Mustang Creek (Merced County)
 
LOE ID: 68031
 
Pollutant: Zinc
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 8
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed AgWaiver data for Mustang Creek (Merced County) to determine beneficial use support and results are as follows: 0 of 8 samples exceed the criterion for Zinc.
Data Reference: Data for Various Pollutants in East San Joaquin, 2004-2009.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The California Toxics Rule (CTR) lists criterion continuous concentrations (4-day average) to protect aquatic life in freshwater. The chromium criterion in freshwater is hardness-dependent for each sample and varies based on the ambient hardness during sampling. Section (b)(1) in CTR contains the hardness-dependent formula for metals criteria.
Objective/Criterion Reference: Code of Federal Regulations 40 part 131.38 Establishment of numeric criteria for priority toxic pollutants for the State of California. 7/1/2011 Edition
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Data for this line of evidence for Mustang Creek (Merced County) was collected at 1 monitoring site [ Mustang Creek @ East Ave - 535XMCAEA]
Temporal Representation: Data was collected over the time period 2/7/2009-4/20/2010.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: The Quality Assurance Project Plan by the East San Joaquin Water Quality Coalition, Revision 1.0 was followed.
QAPP Information Reference(s): Quality Assurance Project Plan by the East San Joaquin Water Quality Coalition, Revision 1.0.
 
Line of Evidence (LOE) for Decision ID 118708, Zinc
Region 5     
Mustang Creek (Merced County)
 
LOE ID: 68023
 
Pollutant: Zinc
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 8
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Ag Waiver data for Mustang Creek (Merced County) to determine beneficial use support and results are as follows: 0 of 8 samples exceed the criterion for Zinc.
Data Reference: Data for Various Pollutants in East San Joaquin, 2004-2009.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The California secondary maximum contaminant level for zinc is 5.0 mg/L.
Objective/Criterion Reference: Secondary Maximum Contaminant Levels and Compliance. CCR Title 22 section 64449.
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Data for this line of evidence for Mustang Creek (Merced County) was collected at 1 monitoring site [Mustang Creek @ East Ave - 535XMCAEA]
Temporal Representation: Data was collected over the time period 2/7/2009-4/20/2010.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: The Quality Assurance Project Plan by the East San Joaquin Water Quality Coalition, Revision 1.0 was followed.
QAPP Information Reference(s): Quality Assurance Project Plan by the East San Joaquin Water Quality Coalition, Revision 1.0.
 
Line of Evidence (LOE) for Decision ID 118708, Zinc
Region 5     
Mustang Creek (Merced County)
 
LOE ID: 194210
 
Pollutant: Zinc
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 2
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed East San Joaquin Water Quality Coalition data for Mustang Creek (Merced County) to determine beneficial use support and results are as follows: 0 of 2 samples exceeded the water quality threshold for Zinc.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The California Secondary Maximum Contaminant Level for zinc incorporated by reference in the Water Quality Control Plan for the Sacramento and San Joaquin River Basins is 5.0 mg/L.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (535XMCAEA)
Temporal Representation: The samples were collected between the dates of 2013-01-08 and 2013-02-12
Environmental Conditions:
QAPP Information: Michael L. Johnson LLC. 2015. Quality Assurance Project Plan for Monitoring by the East San Joaquin Water Quality Coalition.
QAPP Information Reference(s): Quality Assurance Project Plan for Monitoring by the East San Joaquin Water Quality Coalition
 
 
DECISION ID
122994
Region 5     
Mustang Creek (Merced County)
 
Pollutant: pH
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: Do Not List on 303(d) list (TMDL required list)(2018)
Revision Status Revised
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: This pollutant is being considered for placement on the CWA section 303(d) List under section 3.2 of the Listing Policy. Under section 3.2 a single line of evidence is necessary to assess listing status.

Four lines of evidence are available in the administrative record to assess this pollutant. Zero of the 16 samples exceeded the OBJECTIVE for COLD, REC-1, and REC-2. Zero of the 18 samples exceeded the OBJECTIVE for MUN.

Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the CWA section 303(d) List.

This conclusion is based on the staff findings that:
1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy.
2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy.
3. Zero of the 16 samples exceeded the OBJECTIVE for COLD, REC-1, and REC-2. Zero of the 18 samples exceeded the OBJECTIVE for MUN. This sample size is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating. A minimum of 26 samples is needed to determine if a beneficial use is fully supported using table 3.2.
4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
 
Regional Board Decision Recommendation: This decision was made by SWRCB staff.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of the available data and information, SWRCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because it cannot be determined if applicable water quality standards are not being exceeded.
 
 
Line of Evidence (LOE) for Decision ID 122994, pH
Region 5     
Mustang Creek (Merced County)
 
LOE ID: 79644
 
Pollutant: pH
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 18
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: State Water Board staff assessed ILRP data for Mustang Creek (Merced County) to determine beneficial use support and results are as follows: 3 of 21 samples exceed the criterion for pH.
Data Reference: Data for Various Pollutants in East San Joaquin, 2004-2009.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan, Central Valley Region Sacramento River Basin and San Joaquin River Basin: pH should not be lower than 6.5 or higher than 8.5.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Data for this line of evidence for Mustang Creek (Merced County) was collected at 1 monitoring site [ Mustang Creek @ East Ave - 535XMCAEA]
Temporal Representation: Data was collected over the time period 2/12/2007-7/20/2010.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: The Quality Assurance Project Plan by the East San Joaquin Water Quality Coalition, Revision 1.0 was followed.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 122994, pH
Region 5     
Mustang Creek (Merced County)
 
LOE ID: 229413
 
Pollutant: pH
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 16
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed East San Joaquin Water Quality Coalition data for Mustang Creek (Merced County) to determine beneficial use support and results are as follows: 0 of 16 samples exceeded the water quality threshold for pH.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan, Central Valley Region Sacramento River Basin and San Joaquin River Basin: pH should not be lower than 6.5 or higher than 8.5.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (535XMCAEA)
Temporal Representation: The samples were collected between the dates of 2013-01-08 and 2016-12-09
Environmental Conditions:
QAPP Information: Michael L. Johnson LLC. 2015. Quality Assurance Project Plan for Monitoring by the East San Joaquin Water Quality Coalition.
QAPP Information Reference(s): Quality Assurance Project Plan for Monitoring by the East San Joaquin Water Quality Coalition
 
Line of Evidence (LOE) for Decision ID 122994, pH
Region 5     
Mustang Creek (Merced County)
 
LOE ID: 229021
 
Pollutant: pH
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Water Contact Recreation
 
Number of Samples: 16
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed East San Joaquin Water Quality Coalition data for Mustang Creek (Merced County) to determine beneficial use support and results are as follows: 0 of 16 samples exceeded the water quality threshold for pH.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan, Central Valley Region Sacramento River Basin and San Joaquin River Basin: pH should not be lower than 6.5 or higher than 8.5.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (535XMCAEA)
Temporal Representation: The samples were collected between the dates of 2013-01-08 and 2016-12-09
Environmental Conditions:
QAPP Information: Michael L. Johnson LLC. 2015. Quality Assurance Project Plan for Monitoring by the East San Joaquin Water Quality Coalition.
QAPP Information Reference(s): Quality Assurance Project Plan for Monitoring by the East San Joaquin Water Quality Coalition
 
Line of Evidence (LOE) for Decision ID 122994, pH
Region 5     
Mustang Creek (Merced County)
 
LOE ID: 228801
 
Pollutant: pH
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Non-Contact Recreation
 
Number of Samples: 16
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed East San Joaquin Water Quality Coalition data for Mustang Creek (Merced County) to determine beneficial use support and results are as follows: 0 of 16 samples exceeded the water quality threshold for pH.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan, Central Valley Region Sacramento River Basin and San Joaquin River Basin: pH should not be lower than 6.5 or higher than 8.5.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (535XMCAEA)
Temporal Representation: The samples were collected between the dates of 2013-01-08 and 2016-12-09
Environmental Conditions:
QAPP Information: Michael L. Johnson LLC. 2015. Quality Assurance Project Plan for Monitoring by the East San Joaquin Water Quality Coalition.
QAPP Information Reference(s): Quality Assurance Project Plan for Monitoring by the East San Joaquin Water Quality Coalition
 
 
DECISION ID
118692
Region 5     
Mustang Creek (Merced County)
 
Pollutant: Copper
Final Listing Decision: List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: Do Not List on 303(d) list (TMDL required list)(2018)
Revision Status Revised
Sources: A Source Unknown
Expected TMDL Completion Date: 2035
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: This pollutant is being considered for placement on the CWA section 303(d) List under section 3.1 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status.

Five lines of evidence are available in the administrative record to assess this pollutant. Nine of 19 water samples reported as a dissolved concentration exceed the criteria for COLD, zero of 19 water samples reported as a dissolved concentration exceed the water quality objective for MUN and zero of eight water samples exceed the criteria for WARM.

Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification in favor of placing this water segment-pollutant combination on the CWA section 303(d) List.

This conclusion is based on the staff findings that:
1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy.
2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy.
3. Nine of 19 water samples reported as a dissolved concentration exceed the criteria for COLD and this exceeds the allowable frequency listed in Table 3.1 of the Listing Policy.
4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should be placed on the section 303(d) list because applicable water quality standards are exceeded and a pollutant contributes to or causes the problem.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.
 
 
Line of Evidence (LOE) for Decision ID 118692, Copper
Region 5     
Mustang Creek (Merced County)
 
LOE ID: 187776
 
Pollutant: Copper
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 19
Number of Exceedances: 9
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed East San Joaquin Water Quality Coalition data for Mustang Creek (Merced County) to determine beneficial use support and results are as follows: 9 of 19 samples exceeded the water quality threshold for Copper.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: California Toxics Rule (CTR) lists criterion continuous concentrations to protect aquatic life in freshwater. The criterion in freshwater is hardness dependent for each sample and varies based on the ambient hardness during sampling. Section (b)(1) in CTR contains the hardness dependent formula for the metals criterion.
Objective/Criterion Reference: Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (535XMCAEA)
Temporal Representation: The samples were collected between the dates of 2013-01-08 and 2018-03-05
Environmental Conditions:
QAPP Information: Michael L. Johnson LLC. 2015. Quality Assurance Project Plan for Monitoring by the East San Joaquin Water Quality Coalition.
QAPP Information Reference(s): Quality Assurance Project Plan for Monitoring by the East San Joaquin Water Quality Coalition
 
Line of Evidence (LOE) for Decision ID 118692, Copper
Region 5     
Mustang Creek (Merced County)
 
LOE ID: 68050
 
Pollutant: Copper
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 8
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Ag Waiver data for Mustang Creek (Merced County) to determine beneficial use support and results are as follows: 0 of 8 samples exceed the criterion for Copper.
Data Reference: Data for Various Pollutants in East San Joaquin, 2004-2009.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The California secondary maximum contaminant level for copper is 1.0 mg/L.
Objective/Criterion Reference: Secondary Maximum Contaminant Levels and Compliance. CCR Title 22 section 64449.
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Data for this line of evidence for Mustang Creek (Merced County) was collected at 1 monitoring site [Mustang Creek @ East Ave - 535XMCAEA]
Temporal Representation: Data was collected over the time period 2/7/2009-4/20/2010.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: The Quality Assurance Project Plan by the East San Joaquin Water Quality Coalition, Revision 1.0 was followed.
QAPP Information Reference(s): Quality Assurance Project Plan by the East San Joaquin Water Quality Coalition, Revision 1.0.
 
Line of Evidence (LOE) for Decision ID 118692, Copper
Region 5     
Mustang Creek (Merced County)
 
LOE ID: 68051
 
Pollutant: Copper
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 8
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed AgWaiver data for Mustang Creek (Merced County) to determine beneficial use support and results are as follows: 0 of 8 samples exceed the criterion for Copper.
Data Reference: Data for Various Pollutants in East San Joaquin, 2004-2009.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The California Toxics Rule (CTR) lists criterion continuous concentrations (4-day average) to protect aquatic life in freshwater. The chromium criterion in freshwater is hardness-dependent for each sample and varies based on the ambient hardness during sampling. Section (b)(1) in CTR contains the hardness-dependent formula for metals criteria.
Objective/Criterion Reference: Code of Federal Regulations 40 part 131.38 Establishment of numeric criteria for priority toxic pollutants for the State of California. 7/1/2011 Edition
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Data for this line of evidence for Mustang Creek (Merced County) was collected at 1 monitoring site [ Mustang Creek @ East Ave - 535XMCAEA]
Temporal Representation: Data was collected over the time period 2/7/2009-4/20/2010.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: The Quality Assurance Project Plan by the East San Joaquin Water Quality Coalition, Revision 1.0 was followed.
QAPP Information Reference(s): Quality Assurance Project Plan by the East San Joaquin Water Quality Coalition, Revision 1.0.
 
Line of Evidence (LOE) for Decision ID 118692, Copper
Region 5     
Mustang Creek (Merced County)
 
LOE ID: 187757
 
Pollutant: Copper
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 19
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed East San Joaquin Water Quality Coalition data for Mustang Creek (Merced County) to determine beneficial use support and results are as follows: 0 of 19 samples exceeded the water quality threshold for Copper.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The California Secondary Maximum Contaminant Level for copper incorporated by reference in the Water Quality Control Plan for the Sacramento and San Joaquin River Basins is 1.0 mg/L.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (535XMCAEA)
Temporal Representation: The samples were collected between the dates of 2013-01-08 and 2018-03-05
Environmental Conditions:
QAPP Information: Michael L. Johnson LLC. 2015. Quality Assurance Project Plan for Monitoring by the East San Joaquin Water Quality Coalition.
QAPP Information Reference(s): Quality Assurance Project Plan for Monitoring by the East San Joaquin Water Quality Coalition
 
Line of Evidence (LOE) for Decision ID 118692, Copper
Region 5     
Mustang Creek (Merced County)
 
LOE ID: 187948
 
Pollutant: Copper
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 5
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed East San Joaquin Water Quality Coalition data for Mustang Creek (Merced County) to determine beneficial use support and results are as follows: 0 of 5 samples exceeded the water quality threshold for Copper.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The California Secondary Maximum Contaminant Level for copper incorporated by reference in the Water Quality Control Plan for the Sacramento and San Joaquin River Basins is 1.0 mg/L.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (535XMCAEA)
Temporal Representation: The samples were collected between the dates of 2013-01-08 and 2014-04-08
Environmental Conditions:
QAPP Information: Michael L. Johnson LLC. 2015. Quality Assurance Project Plan for Monitoring by the East San Joaquin Water Quality Coalition.
QAPP Information Reference(s): Quality Assurance Project Plan for Monitoring by the East San Joaquin Water Quality Coalition
 
 
DECISION ID
94783
Region 5     
Mustang Creek (Merced County)
 
Pollutant: Ammonia as N, Total
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: Do Not List on 303(d) list (TMDL required list)(2016)
Revision Status Original
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: This pollutant is being considered for placement on the CWA section 303(d) List under section 3.1 of the Listing Policy. Under section 3.1 one line of evidence is necessary to assess listing status.

One line of evidence is available in the administrative record to assess this pollutant. Zero of the eight samples exceed the Evaluation Guideline.

Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the CWA section 303(d) List.

This conclusion is based on the staff findings that:
1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy.
2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy.
3. Zero of eight samples exceeded Evaluation Guideline, and this sample size is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating. A minimum of 16 samples is needed to determine if a beneficial use is fully supported using table 3.1.
4. Pursuant to Section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.
 
 
Line of Evidence (LOE) for Decision ID 94783, Ammonia as N, Total
Region 5     
Mustang Creek (Merced County)
 
LOE ID: 79018
 
Pollutant: Ammonia as N, Total
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
Aquatic Life Use: Warm Freshwater Habitat
 
Number of Samples: 8
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Eight water samples collected from Mud Slough, North (upstream of San Luis Drain) East San Joaquin Water Quality Coalition were analyzed for ammonia, pH and temperature. None of the eight samples exceeded the calculated ammonia CMC values.
Data Reference: Data for Various Pollutants in Southern San Joaquin Water Quality Coalition, 2004-2009.
 
SWAMP Data:
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that produce detrimental physiological responses in human, plant, animal, or aquatic life. This objective applies regardless of whether the toxicity is caused by a single substance or the interactive effect of multiple substances.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: Per the National Recommended Water Quality Criteria (USEPA 2006): The 1-hour average concentration (acute criterion or CMC) of total ammonia nitrogen (in mg N/L) for freshwater where salmonid fish are present, which is not to be exceeded more than once every three years on average, is calculated using the following equation: CMC=0.275/(1+10^(7.204 - pH)) + 39.0/(1+10^(pH - 7.204)).
Guideline Reference: Data for Various Pollutants in South San Joaquin Irrigation District, 2004-2008.
Guideline Reference: National Recommended Water Quality Criteria. United States Environmental Protection Agency. Office of Water. Office of Science and Technology
 
Spatial Representation: The eight water samples were collected from Mustang Creek (Merced County) at one monitoring site [Mustang Creek @ East Ave - 535XMCAEA]
Temporal Representation: Eight water samples were collected from Mustang Creek (Merced County) between 2/7/2009 and 4/20/2010
Environmental Conditions:
QAPP Information: Data for this line of evidence was collected as part of the Irrigated Lands Regulatory Program.
QAPP Information Reference(s):
 
 
DECISION ID
67657
Region 5     
Mustang Creek (Merced County)
 
Pollutant: Arsenic
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: Do Not List on 303(d) list (TMDL required list)(2016)
Revision Status Original
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: This pollutant is being considered for placement on the CWA section 303(d) List under section 3.1 of the Listing Policy. Under section 3.1a two line(s) of evidence are necessary to assess listing status.

Two lines of evidence are available in the administrative record to assess this pollutant. Zero of the three samples exceed each of the MUN and WARM water quality objectives.

Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the CWA section 303(d) List.

This conclusion is based on the staff findings that:
1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy.
2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy.
3. Zero of three samples exceed each of the MUN and WARM water quality objectives, and this sample size is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating. A minimum of 16 samples is needed to determine if a beneficial use is fully supported using table 3.1.
4. Pursuant to Section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.
 
 
Line of Evidence (LOE) for Decision ID 67657, Arsenic
Region 5     
Mustang Creek (Merced County)
 
LOE ID: 68029
 
Pollutant: Arsenic
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 3
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Ag Waiver data for Mustang Creek (Merced County) to determine beneficial use support and results are as follows: 0 of 3 samples exceed the criterion for Arsenic.
Data Reference: Data for Various Pollutants in East San Joaquin, 2004-2009.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The California primary maximum contaminant level for arsenic is 0.010 mg/L.
Objective/Criterion Reference: Maximum Contaminant Levels for organic and inorganic chemicals. CCR Title 22
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Data for this line of evidence for Mustang Creek (Merced County) was collected at 1 monitoring site [Mustang Creek @ East Ave - 535XMCAEA]
Temporal Representation: Data was collected over the time period 2/7/2009-12/15/2009.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: The Quality Assurance Project Plan by the East San Joaquin Water Quality Coalition, Revision 1.0 was followed.
QAPP Information Reference(s): Quality Assurance Project Plan by the East San Joaquin Water Quality Coalition, Revision 1.0.
 
Line of Evidence (LOE) for Decision ID 67657, Arsenic
Region 5     
Mustang Creek (Merced County)
 
LOE ID: 68030
 
Pollutant: Arsenic
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 3
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Ag Waiver data for Mustang Creek (Merced County) to determine beneficial use support and results are as follows: 0 of 3 samples exceed the criterion for Arsenic.
Data Reference: Data for Various Pollutants in East San Joaquin, 2004-2009.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The dissolved arsenic criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in freshwater for dissolved arsenic is 0.150 mg/L (California Toxics Rule, 2000).
Objective/Criterion Reference: Code of Federal Regulations 40 part 131.38 Establishment of numeric criteria for priority toxic pollutants for the State of California. 7/1/2011 Edition
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Data for this line of evidence for Mustang Creek (Merced County) was collected at 1 monitoring site [Mustang Creek @ East Ave - 535XMCAEA]
Temporal Representation: Data was collected over the time period 2/7/2009-12/15/2009.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: The Quality Assurance Project Plan by the East San Joaquin Water Quality Coalition, Revision 1.0 was followed.
QAPP Information Reference(s): Quality Assurance Project Plan by the East San Joaquin Water Quality Coalition, Revision 1.0.
 
 
DECISION ID
67606
Region 5     
Mustang Creek (Merced County)
 
Pollutant: Cadmium
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: Do Not List on 303(d) list (TMDL required list)(2016)
Revision Status Original
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: This pollutant is being considered for placement on the CWA section 303(d) List under section 3.1 of the Listing Policy. Under section 3.1a two line(s) of evidence are necessary to assess listing status.

Two lines of evidence are available in the administrative record to assess this pollutant. Zero of the three samples exceed each of the MUN and WARM water quality objectives.

Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the CWA section 303(d) List.

This conclusion is based on the staff findings that:
1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy.
2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy.
3. Zero of three samples exceed each of the MUN and WARM water quality objectives, and this sample size is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating. A minimum of 16 samples is needed to determine if a beneficial use is fully supported using table 3.1.
4. Pursuant to Section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.
 
 
Line of Evidence (LOE) for Decision ID 67606, Cadmium
Region 5     
Mustang Creek (Merced County)
 
LOE ID: 68040
 
Pollutant: Cadmium
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 3
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Ag Waiver data for Mustang Creek (Merced County) to determine beneficial use support and results are as follows: 0 of 3 samples exceed the criterion for Cadmium.
Data Reference: Data for Various Pollutants in East San Joaquin, 2004-2009.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The California primary maximum contaminant level for cadmium is 5 ug/L.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Data for this line of evidence for Mustang Creek (Merced County) was collected at 1 monitoring site [Mustang Creek @ East Ave - 535XMCAEA]
Temporal Representation: Data was collected over the time period 2/7/2009-12/15/2009.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: The Quality Assurance Project Plan by the East San Joaquin Water Quality Coalition, Revision 1.0 was followed.
QAPP Information Reference(s): Quality Assurance Project Plan by the East San Joaquin Water Quality Coalition, Revision 1.0.
 
Line of Evidence (LOE) for Decision ID 67606, Cadmium
Region 5     
Mustang Creek (Merced County)
 
LOE ID: 68046
 
Pollutant: Cadmium
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 3
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed AgWaiver data for Mustang Creek (Merced County) to determine beneficial use support and results are as follows: 0 of 3 samples exceed the criterion for Cadmium.
Data Reference: Data for Various Pollutants in East San Joaquin, 2004-2009.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The California Toxics Rule (CTR) lists criterion continuous concentrations (4-day average) to protect aquatic life in freshwater. The cadmium criterion in freshwater is hardness-dependent for each sample and varies based on the ambient hardness during sampling. Section (b)(1) in CTR contains the hardness dependent formula for the metals criterion.
Objective/Criterion Reference: Code of Federal Regulations 40 part 131.38 Establishment of numeric criteria for priority toxic pollutants for the State of California. 7/1/2011 Edition
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Data for this line of evidence for Mustang Creek (Merced County) was collected at 1 monitoring site [ Mustang Creek @ East Ave - 535XMCAEA]
Temporal Representation: Data was collected over the time period 2/7/2009-12/15/2009.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: The Quality Assurance Project Plan by the East San Joaquin Water Quality Coalition, Revision 1.0 was followed.
QAPP Information Reference(s): Quality Assurance Project Plan by the East San Joaquin Water Quality Coalition, Revision 1.0.
 
 
DECISION ID
93098
Region 5     
Mustang Creek (Merced County)
 
Pollutant: DDD (Dichlorodiphenyldichloroethane)
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: Do Not List on 303(d) list (TMDL required list)(2016)
Revision Status Original
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: This pollutant is being considered for placement on the CWA section 303(d) List under section 3.1 of the Listing Policy. Under section 3.1 a one line(s) of evidence are necessary to assess listing status.

One line of evidence is available in the administrative record to assess this pollutant. Zero of the zero samples exceed the Criteria/Objective.

Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the CWA section 303(d) List.

This conclusion is based on the staff findings that:
1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy.
2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy.
3. Zero of zero samples exceeded Criteria/Objective and this sample size is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating. A minimum of 16 samples is needed to determine if a beneficial use is fully supported using table 3.1.
4. Pursuant to Section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.
 
 
Line of Evidence (LOE) for Decision ID 93098, DDD (Dichlorodiphenyldichloroethane)
Region 5     
Mustang Creek (Merced County)
 
LOE ID: 78842
 
Pollutant: DDD (Dichlorodiphenyldichloroethane)
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 0
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: The DDD method detection limit for all nine analytical sample results collected from Mustang Creek (Merced County) is greater than the criterion; therefore, the data could not be assessed with the accuracy required by the Listing Policy.
Data Reference: Data for Various Pollutants in Sacramento Valley Water Quality Coalition, 2005-2009.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Sacramento/San Joaquin River Basin Plan (CVRWQCB, 2007) Pesticides: Total identifiable persistent chlorinated hydrocarbon pesticides shall not be present in the water column at concentrations detectable within the accuracy of analytical methods approved by the Environmental Protection Agency or the Executive Officer.- California Toxics Rule Criteria (USEPA, 2000), for Inland Surface Waters based on drinking water and aquatic organism consumption. The criteria are based on human health protection for carcinogenicity at 1-in-a-million risk level (30-day average) with a limit of 0.00083 ug/L for DDD
Objective/Criterion Reference: Code of Federal Regulations 40 part 131.38 Establishment of numeric criteria for priority toxic pollutants for the State of California. 7/1/2011 Edition
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Nine water samples were collected from one monitoring site on Mustang Creek (Merced County) [Mustang Creek @ East Ave - 535XMCAEA] and they were analyzed for DDD(p,p').
Temporal Representation: Data was collected intermittently between 2/12/2007 and 12/15/2009.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: The Quality Assurance Project Plan for Sacramento Valley Water Quality Coalition was followed.
QAPP Information Reference(s): Quality Assurance Project Plan for Sacramento Valley Water Quality Coalition.
 
 
DECISION ID
67662
Region 5     
Mustang Creek (Merced County)
 
Pollutant: DDE (Dichlorodiphenyldichloroethylene)
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: Do Not List on 303(d) list (TMDL required list)(2016)
Revision Status Original
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: This pollutant is being considered for placement on the CWA section 303(d) List under section 3.1 of the Listing Policy. Under section 3.1a one line(s) of evidence are necessary to assess listing status.

One line of evidence is available in the administrative record to assess this pollutant. Zero of the zero samples exceed the Criteria/Objective.

Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the CWA section 303(d) List.

This conclusion is based on the staff findings that:
1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy.
2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy.
3. Zero of zero samples exceeded Criteria/Objective and this sample size is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating. A minimum of 16 samples is needed to determine if a beneficial use is fully supported using table 3.1.
4. Pursuant to Section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.
 
 
Line of Evidence (LOE) for Decision ID 67662, DDE (Dichlorodiphenyldichloroethylene)
Region 5     
Mustang Creek (Merced County)
 
LOE ID: 78894
 
Pollutant: DDE (Dichlorodiphenyldichloroethylene)
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 0
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: The DDE method detection limit for all nine analytical sample results collected from Mustang Creek (Merced County) is greater than the criterion; therefore, the data could not be assessed with the accuracy required by the Listing Policy.
Data Reference: Data for Various Pollutants in Sacramento Valley Water Quality Coalition, 2005-2009.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Sacramento/San Joaquin River Basin Plan (CVRWQCB, 2007) Pesticides: Total identifiable persistent chlorinated hydrocarbon pesticides shall not be present in the water column at concentrations detectable within the accuracy of analytical methods approved by the Environmental Protection Agency or the Executive Officer.- California Toxics Rule Criteria (USEPA, 2000), for Inland Surface Waters based on drinking water and aquatic organism consumption. The criteria are based on human health protection for carcinogenicity at 1-in-a-million risk level (30-day average) with a limit of 0.00059 ug/L for DDE
Objective/Criterion Reference: Code of Federal Regulations 40 part 131.38 Establishment of numeric criteria for priority toxic pollutants for the State of California. 7/1/2011 Edition
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Nine water samples were collected from one monitoring site on Mustang Creek (Merced County) [Mustang Creek @ East Ave - 535XMCAEA] and they were analyzed for DDE(p,p').
Temporal Representation: Data was collected intermittently between 2/12/2007 and 12/15/2009.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: The Quality Assurance Project Plan for Sacramento Valley Water Quality Coalition was followed.
QAPP Information Reference(s): Quality Assurance Project Plan for Sacramento Valley Water Quality Coalition.
 
 
DECISION ID
93099
Region 5     
Mustang Creek (Merced County)
 
Pollutant: DDT (Dichlorodiphenyltrichloroethane)
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: Do Not List on 303(d) list (TMDL required list)(2016)
Revision Status Original
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: This pollutant is being considered for placement on the CWA section 303(d) List under section 3.1 of the Listing Policy. Under section 3.1 a one line(s) of evidence are necessary to assess listing status.

Two lines of evidence are available in the administrative record to assess this pollutant. Zero of the zero samples exceed each of the MUN and WARM water Criteria/Objective.

Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the CWA section 303(d) List.

This conclusion is based on the staff findings that:
1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy.
2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy.
3. Zero of the zero samples exceed each of the MUN and WARM water Criteria/Objective and this sample size is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating. A minimum of 16 samples is needed to determine if a beneficial use is fully supported using table 3.1.
4. Pursuant to Section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.
 
 
Line of Evidence (LOE) for Decision ID 93099, DDT (Dichlorodiphenyltrichloroethane)
Region 5     
Mustang Creek (Merced County)
 
LOE ID: 68066
 
Pollutant: DDT (Dichlorodiphenyltrichloroethane)
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 0
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Ag Waiver data for Mustang Creek (Merced County) to determine beneficial use support and results are as follows: 0 of 0 samples exceed the criterion for DDT(p,p). Nine samples were not used in the assessment because the laboratory data reporting limit was above the objective and therefore the results could not be quantified with the level of certainty required by the Listing Policy.
Data Reference: Data for Various Pollutants in East San Joaquin, 2004-2009.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The DDT criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in freshwater is 0.001 ug/L (California Toxics Rule, 2000).
Objective/Criterion Reference: Code of Federal Regulations 40 part 131.38 Establishment of numeric criteria for priority toxic pollutants for the State of California. 7/1/2011 Edition
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Data for this line of evidence for Mustang Creek (Merced County) was collected at 1 monitoring site [Mustang Creek @ East Ave - 535XMCAEA]
Temporal Representation: Data was collected over the time period 2/12/2007-12/15/2009.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: The Quality Assurance Project Plan by the East San Joaquin Water Quality Coalition, Revision 1.0 was followed.
QAPP Information Reference(s): Quality Assurance Project Plan by the East San Joaquin Water Quality Coalition, Revision 1.0.
 
Line of Evidence (LOE) for Decision ID 93099, DDT (Dichlorodiphenyltrichloroethane)
Region 5     
Mustang Creek (Merced County)
 
LOE ID: 68067
 
Pollutant: DDT (Dichlorodiphenyltrichloroethane)
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 0
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Ag Waiver data for Mustang Creek (Merced County) to determine beneficial use support and results are as follows: 0 of 0 samples exceed the criterion for DDT(p,p). Nine samples were not used in the assessment because the laboratory data reporting limit was above the objective and therefore the results could not be quantified with the level of certainty required by the Listing Policy.
Data Reference: Data for Various Pollutants in East San Joaquin, 2004-2009.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The criterion for total DDT to protect human health from consumption of water and organisms is 0.00059 ug/L (California Toxics Rule).
Objective/Criterion Reference: Code of Federal Regulations 40 part 131.38 Establishment of numeric criteria for priority toxic pollutants for the State of California. 7/1/2011 Edition
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Data for this line of evidence for Mustang Creek (Merced County) was collected at 1 monitoring site [Mustang Creek @ East Ave - 535XMCAEA]
Temporal Representation: Data was collected over the time period 2/12/2007-12/15/2009.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: The Quality Assurance Project Plan by the East San Joaquin Water Quality Coalition, Revision 1.0 was followed.
QAPP Information Reference(s): Quality Assurance Project Plan by the East San Joaquin Water Quality Coalition, Revision 1.0.
 
 
DECISION ID
93158
Region 5     
Mustang Creek (Merced County)
 
Pollutant: Dieldrin
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: Do Not List on 303(d) list (TMDL required list)(2016)
Revision Status Original
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: This pollutant is being considered for placement on the CWA section 303(d) List under section 3.1 of the Listing Policy. Under section 3.1 a one line(s) of evidence are necessary to assess listing status.

Two lines of evidence are available in the administrative record to assess this pollutant. Zero of zero samples exceed the MUN, and zero of nine samples exceed the WARM water Criteria/Objective.

Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the CWA section 303(d) List.

This conclusion is based on the staff findings that:
1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy.
2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy.
3. Zero of zero water samples exceed the MUN objective, and zero of nine water samples exceed the WARM water objective, and this sample size is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating. A minimum of 16 samples is needed to determine if a beneficial use is fully supported using table 3.1.
4. Pursuant to Section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.
 
 
Line of Evidence (LOE) for Decision ID 93158, Dieldrin
Region 5     
Mustang Creek (Merced County)
 
LOE ID: 68070
 
Pollutant: Dieldrin
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 0
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Ag Waiver data for Mustang Creek (Merced County) to determine beneficial use support and results are as follows: 0 of 0 samples exceed the criterion for Dieldrin. Nine samples were not used in the assessment because the laboratory data reporting limit(s) was above the objective and therefore the results could not be quantified with the level of certainty required by the Listing Policy.
Data Reference: Data for Various Pollutants in East San Joaquin, 2004-2009.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The criterion for Dieldrin to protect human health from the consumption of water and organisms is 0.00014 ug/L (California Toxics Rule).
Objective/Criterion Reference: Code of Federal Regulations 40 part 131.38 Establishment of numeric criteria for priority toxic pollutants for the State of California. 7/1/2011 Edition
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Data for this line of evidence for Mustang Creek (Merced County) was collected at 1 monitoring site [Mustang Creek @ East Ave - 535XMCAEA]
Temporal Representation: Data was collected over the time period 2/12/2007-12/15/2009.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: The Quality Assurance Project Plan by the East San Joaquin Water Quality Coalition, Revision 1.0 was followed.
QAPP Information Reference(s): Quality Assurance Project Plan by the East San Joaquin Water Quality Coalition, Revision 1.0.
 
Line of Evidence (LOE) for Decision ID 93158, Dieldrin
Region 5     
Mustang Creek (Merced County)
 
LOE ID: 68076
 
Pollutant: Dieldrin
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 9
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Ag Waiver data for Mustang Creek (Merced County) to determine beneficial use support and results are as follows: 0 of 9 samples exceed the criterion for Dieldrin.
Data Reference: Data for Various Pollutants in East San Joaquin, 2004-2009.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The Dieldrin criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in freshwater is 0.056 ug/L (California Toxics Rule, 2000).
Objective/Criterion Reference: Code of Federal Regulations 40 part 131.38 Establishment of numeric criteria for priority toxic pollutants for the State of California. 7/1/2011 Edition
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Data for this line of evidence for Mustang Creek (Merced County) was collected at 1 monitoring site [Mustang Creek @ East Ave - 535XMCAEA]
Temporal Representation: Data was collected over the time period 2/12/2007-12/15/2009.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: The Quality Assurance Project Plan by the East San Joaquin Water Quality Coalition, Revision 1.0 was followed.
QAPP Information Reference(s): Quality Assurance Project Plan by the East San Joaquin Water Quality Coalition, Revision 1.0.
 
 
DECISION ID
91626
Region 5     
Mustang Creek (Merced County)
 
Pollutant: Endrin
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: Do Not List on 303(d) list (TMDL required list)(2016)
Revision Status Original
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: This pollutant is being considered for placement on the CWA section 303(d) List under section 3.1 of the Listing Policy. Under section 3.1 a one line(s) of evidence are necessary to assess listing status.

Two lines of evidence are available in the administrative record to assess this pollutant. Zero of the nine water samples exceed either the MUN or WARM objectives.

Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the CWA section 303(d) List.

This conclusion is based on the staff findings that:
1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy.
2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy.
3. Zero of the nine samples exceed each of the MUN and WARM water Criteria/Objective and this sample size is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating. A minimum of 16 samples is needed to determine if a beneficial use is fully supported using table 3.1.
4. Pursuant to Section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.
 
 
Line of Evidence (LOE) for Decision ID 91626, Endrin
Region 5     
Mustang Creek (Merced County)
 
LOE ID: 68081
 
Pollutant: Endrin
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 9
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Ag Waiver data for Mustang Creek (Merced County) to determine beneficial use support and results are as follows: 0 of 9 samples exceed the criterion for Endrin.
Data Reference: Data for Various Pollutants in East San Joaquin, 2004-2009.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The Endrin criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in freshwater is 0.036 ug/L. (California Toxics Rule, 2000)
Objective/Criterion Reference: Code of Federal Regulations 40 part 131.38 Establishment of numeric criteria for priority toxic pollutants for the State of California. 7/1/2011 Edition
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Data for this line of evidence for Mustang Creek (Merced County) was collected at 1 monitoring site [Mustang Creek @ East Ave - 535XMCAEA]
Temporal Representation: Data was collected over the time period 2/12/2007-12/15/2009.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: The Quality Assurance Project Plan by the East San Joaquin Water Quality Coalition, Revision 1.0 was followed.
QAPP Information Reference(s): Quality Assurance Project Plan by the East San Joaquin Water Quality Coalition, Revision 1.0.
 
Line of Evidence (LOE) for Decision ID 91626, Endrin
Region 5     
Mustang Creek (Merced County)
 
LOE ID: 68080
 
Pollutant: Endrin
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 9
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Ag Waiver data for Mustang Creek (Merced County) to determine beneficial use support and results are as follows: 0 of 9 samples exceed the criterion for Endrin.
Data Reference: Data for Various Pollutants in East San Joaquin, 2004-2009.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The Endrin criterion for the protection of human health from the consumption of water and organisms is 0.76 ug/L. (California Toxics Rule, 2000)
Objective/Criterion Reference: Code of Federal Regulations 40 part 131.38 Establishment of numeric criteria for priority toxic pollutants for the State of California. 7/1/2011 Edition
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Data for this line of evidence for Mustang Creek (Merced County) was collected at 1 monitoring site [Mustang Creek @ East Ave - 535XMCAEA]
Temporal Representation: Data was collected over the time period 2/12/2007-12/15/2009.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: The Quality Assurance Project Plan by the East San Joaquin Water Quality Coalition, Revision 1.0 was followed.
QAPP Information Reference(s): Quality Assurance Project Plan by the East San Joaquin Water Quality Coalition, Revision 1.0.
 
 
DECISION ID
67670
Region 5     
Mustang Creek (Merced County)
 
Pollutant: Lead
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: Do Not List on 303(d) list (TMDL required list)(2016)
Revision Status Original
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: This pollutant is being considered for placement on the CWA section 303(d) List under section 3.1 of the Listing Policy. Under section 3.1a one line(s) of evidence are necessary to assess listing status.

One line of evidence is available in the administrative record to assess this pollutant. Zero of the three samples exceed the calculated WARM evaluation guideline.

Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the CWA section 303(d) List.

This conclusion is based on the staff findings that:
1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy.
2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy.
3. Zero of three samples exceeded Criteria/Objective and this sample size is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating. A minimum of 16 samples is needed to determine if a beneficial use is fully supported using table 3.1.
4. Pursuant to Section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.
 
 
Line of Evidence (LOE) for Decision ID 67670, Lead
Region 5     
Mustang Creek (Merced County)
 
LOE ID: 68090
 
Pollutant: Lead
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 3
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed AgWaiver data for Mustang Creek (Merced County) to determine beneficial use support and results are as follows: 0 of 3 samples exceed the criterion for Lead.
Data Reference: Data for Various Pollutants in East San Joaquin, 2004-2009.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The California Toxics Rule (CTR) lists criterion continuous concentrations (4-day average) to protect aquatic life in freshwater. The chromium criterion in freshwater is hardness-dependent for each sample and varies based on the ambient hardness during sampling. Section (b)(1) in CTR contains the hardness-dependent formula for metals criteria.
Objective/Criterion Reference: Code of Federal Regulations 40 part 131.38 Establishment of numeric criteria for priority toxic pollutants for the State of California. 7/1/2011 Edition
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Data for this line of evidence for Mustang Creek (Merced County) was collected at 1 monitoring site [ Mustang Creek @ East Ave - 535XMCAEA]
Temporal Representation: Data was collected over the time period 2/7/2009-12/15/2009.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: The Quality Assurance Project Plan by the East San Joaquin Water Quality Coalition, Revision 1.0 was followed.
QAPP Information Reference(s): Quality Assurance Project Plan by the East San Joaquin Water Quality Coalition, Revision 1.0.
 
 
DECISION ID
93216
Region 5     
Mustang Creek (Merced County)
 
Pollutant: Methoxychlor
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: Do Not List on 303(d) list (TMDL required list)(2016)
Revision Status Original
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: This pollutant is being considered for placement on the CWA section 303(d) List under section 3.1 of the Listing Policy. Under section 3.1 a one line(s) of evidence are necessary to assess listing status.

Two lines of evidence are available in the administrative record to assess this pollutant. Zero of the nine water samples exceed either the MUN objective or the WARM evaluation guideline.

Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the CWA section 303(d) List.

This conclusion is based on the staff findings that:
1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy.
2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy.
3. Zero of the nine samples exceed each of the MUN and WARM water Criteria/Objective and this sample size is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating. A minimum of 16 samples is needed to determine if a beneficial use is fully supported using table 3.1.
4. Pursuant to Section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.
 
 
Line of Evidence (LOE) for Decision ID 93216, Methoxychlor
Region 5     
Mustang Creek (Merced County)
 
LOE ID: 67971
 
Pollutant: Methoxychlor
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 9
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Ag Waiver data for Mustang Creek (Merced County) to determine beneficial use support and results are as follows: 0 of 9 samples exceed the criterion for Methoxychlor.
Data Reference: Data for Various Pollutants in East San Joaquin, 2004-2009.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Total identifiable persistent chlorinated hydrocarbon pesticides shall not be present in the water column at concentrations detectable within the accuracy of analytical methods approved by the Environmental Protection Agency or the Executive Officer (Water Quality Control Plan, Central Valley Region, Sacramento River Basin and San Joaquin River Basin)
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Data for this line of evidence for Mustang Creek (Merced County) was collected at 1 monitoring site [Mustang Creek @ East Ave - 535XMCAEA]
Temporal Representation: Data was collected over the time period 2/12/2007-12/15/2009.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: The Quality Assurance Project Plan by the East San Joaquin Water Quality Coalition, Revision 1.0 was followed.
QAPP Information Reference(s): Quality Assurance Project Plan by the East San Joaquin Water Quality Coalition, Revision 1.0.
 
Line of Evidence (LOE) for Decision ID 93216, Methoxychlor
Region 5     
Mustang Creek (Merced County)
 
LOE ID: 67970
 
Pollutant: Methoxychlor
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 9
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Ag Waiver data for Mustang Creek (Merced County) to determine beneficial use support and results are as follows: 0 of 9 samples exceed the criterion for Methoxychlor.
Data Reference: Data for Various Pollutants in East San Joaquin, 2004-2009.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The California primary maximum contaminant level for Methoxychlor, 30 ug/L, is incorporated by reference into the (Water Quality Control Plan, Central Valley Region, Sacramento and San Joaquin Basins).
Objective/Criterion Reference: Maximum Contaminant Levels for organic and inorganic chemicals. CCR Title 22
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Data for this line of evidence for Mustang Creek (Merced County) was collected at 1 monitoring site [Mustang Creek @ East Ave - 535XMCAEA]
Temporal Representation: Data was collected over the time period 2/12/2007-12/15/2009.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: The Quality Assurance Project Plan by the East San Joaquin Water Quality Coalition, Revision 1.0 was followed.
QAPP Information Reference(s): Quality Assurance Project Plan by the East San Joaquin Water Quality Coalition, Revision 1.0.
 
 
DECISION ID
67668
Region 5     
Mustang Creek (Merced County)
 
Pollutant: Nitrogen, Nitrate
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: Do Not List on 303(d) list (TMDL required list)(2016)
Revision Status Original
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: This pollutant is being considered for placement on the CWA section 303(d) List under section 3.1 of the Listing Policy. Under section 3.1a one line(s) of evidence are necessary to assess listing status.

One line of evidence is available in the administrative record to assess this pollutant. The single water sample does not exceed the water quality objective for the MUN beneficial use.

Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the CWA section 303(d) List.

This conclusion is based on the staff findings that:
1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy.
2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy.
3. The single water sample does not exceed the water quality objective, and this sample size is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating. A minimum of 16 samples is needed to determine if a beneficial use is fully supported using table 3.1.
4. Pursuant to Section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.
 
 
Line of Evidence (LOE) for Decision ID 67668, Nitrogen, Nitrate
Region 5     
Mustang Creek (Merced County)
 
LOE ID: 67991
 
Pollutant: Nitrogen, Nitrate
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Ag Waiver data for Mustang Creek (Merced County) to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Nitrate as N.
Data Reference: Data for Various Pollutants in East San Joaquin, 2004-2009.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The California primary maximum contaminant level for nitrate (NO3 as N) is 10.0 mg/L.
Objective/Criterion Reference: Maximum Contaminant Levels for organic and inorganic chemicals. CCR Title 22
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Data for this line of evidence for Mustang Creek (Merced County) was collected at 1 monitoring site [Mustang Creek @ East Ave - 535XMCAEA]
Temporal Representation: Data was collected on a single day 6/19/2007.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: The Quality Assurance Project Plan by the East San Joaquin Water Quality Coalition, Revision 1.0 was followed.
QAPP Information Reference(s): Quality Assurance Project Plan by the East San Joaquin Water Quality Coalition, Revision 1.0.
 
 
DECISION ID
93218
Region 5     
Mustang Creek (Merced County)
 
Pollutant: Nitrogen, Nitrite
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: Do Not List on 303(d) list (TMDL required list)(2016)
Revision Status Original
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: This pollutant is being considered for placement on the CWA section 303(d) List under section 3.1 of the Listing Policy. Under section 3.1 a one line(s) of evidence are necessary to assess listing status.

One line of evidence is available in the administrative record to assess this pollutant. The single water sample does not exceed the water quality objective for MUN.

Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the CWA section 303(d) List.

This conclusion is based on the staff findings that:
1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy.
2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy.
3. The single water sample does not exceed the water quality objective for MUN, and this sample size is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating. A minimum of 16 samples is needed to determine if a beneficial use is fully supported using table 3.1.
4. Pursuant to Section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.
 
 
Line of Evidence (LOE) for Decision ID 93218, Nitrogen, Nitrite
Region 5     
Mustang Creek (Merced County)
 
LOE ID: 67992
 
Pollutant: Nitrogen, Nitrite
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Ag Waiver data for Mustang Creek (Merced County) to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Nitrite as N.
Data Reference: Data for Various Pollutants in East San Joaquin, 2004-2009.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The California primary maximum contaminant level for nitrite (as N) is 1 mg/L.
Objective/Criterion Reference: Maximum Contaminant Levels for organic and inorganic chemicals. CCR Title 22
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Data for this line of evidence for Mustang Creek (Merced County) was collected at 1 monitoring site [Mustang Creek @ East Ave - 535XMCAEA]
Temporal Representation: Data was collected on a single day 6/19/2007.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: The Quality Assurance Project Plan by the East San Joaquin Water Quality Coalition, Revision 1.0 was followed.
QAPP Information Reference(s): Quality Assurance Project Plan by the East San Joaquin Water Quality Coalition, Revision 1.0.
 
 
DECISION ID
93105
Region 5     
Mustang Creek (Merced County)
 
Pollutant: Thiobencarb/Bolero
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: Do Not List on 303(d) list (TMDL required list)(2016)
Revision Status Original
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: This pollutant is being considered for placement on the CWA section 303(d) List under section 3.1 of the Listing Policy. Under section 3.1 a one line(s) of evidence are necessary to assess listing status.

Two lines of evidence are available in the administrative record to assess this pollutant. Zero of the six water samples exceed either the MUN objective or the WARM objective.

Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the CWA section 303(d) List.

This conclusion is based on the staff findings that:
1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy.
2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy.
3. Zero of six water samples exceed either the MUN evaluation guideline or the WARM water water quality objective, and this sample size is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating. A minimum of 16 samples is needed to determine if a beneficial use is fully supported using table 3.1.
4. Pursuant to Section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.
 
 
Line of Evidence (LOE) for Decision ID 93105, Thiobencarb/Bolero
Region 5     
Mustang Creek (Merced County)
 
LOE ID: 68019
 
Pollutant: Thiobencarb/Bolero
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 6
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Ag Waiver data for Mustang Creek (Merced County) to determine beneficial use support and results are as follows: 0 of 6 samples exceed the criterion for Thiobencarb.
Data Reference: Data for Various Pollutants in East San Joaquin, 2004-2009.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses. (Water Quality Control Plan, Central Valley Region, Sacramento River Basin and San Joaquin River Basin)
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: The Basin Plan states: "Where valid testing has developed 96-hour LC50 values for aquatic organisms..., the Board will consider one tenth of this value for the most sensitive species tested as the upper limit (daily maximum) for the protection of aquatic life... or [O]ther available information on the pesticide..." The evaluation guideline for Thiobencarb, 1.4 ug/L, is a maximum acceptable toxicicant concentration (MATC) calculated for Daphnia magna (Water flea). (USEPA Office of Pesticide Programs Ecotoxicity database)
Guideline Reference: OPP Pesticide Ecotoxicity Database.
 
Spatial Representation: Data for this line of evidence for Mustang Creek (Merced County) was collected at 1 monitoring site [Mustang Creek @ East Ave - 535XMCAEA]
Temporal Representation: Data was collected over the time period 2/12/2007-2/26/2008.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: The Quality Assurance Project Plan by the East San Joaquin Water Quality Coalition, Revision 1.0 was followed.
QAPP Information Reference(s): Quality Assurance Project Plan by the East San Joaquin Water Quality Coalition, Revision 1.0.
 
Line of Evidence (LOE) for Decision ID 93105, Thiobencarb/Bolero
Region 5     
Mustang Creek (Merced County)
 
LOE ID: 68020
 
Pollutant: Thiobencarb/Bolero
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 6
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Ag Waiver data for Mustang Creek (Merced County) to determine beneficial use support and results are as follows: 0 of 6 samples exceed the criterion for Thiobencarb.
Data Reference: Data for Various Pollutants in East San Joaquin, 2004-2009.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Waters designated for use as domestic or municipal supply (MUN) shall not contain concentrations of Thiobencarb in excess of 1.0 µg/L. (Water Quality Control Plan, Central Valley Region, Sacramento River Basin and San Joaquin River Basin)
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Data for this line of evidence for Mustang Creek (Merced County) was collected at 1 monitoring site [Mustang Creek @ East Ave - 535XMCAEA]
Temporal Representation: Data was collected over the time period 2/12/2007-2/26/2008.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: The Quality Assurance Project Plan by the East San Joaquin Water Quality Coalition, Revision 1.0 was followed.
QAPP Information Reference(s): Quality Assurance Project Plan by the East San Joaquin Water Quality Coalition, Revision 1.0.
 
 
DECISION ID
94813
Region 5     
Mustang Creek (Merced County)
 
Pollutant: Toxicity
Final Listing Decision: List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: List on 303(d) list (TMDL required list)(2016)
Revision Status Original
Sources: A Source Unknown
Expected TMDL Completion Date: 2027
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: This pollutant is being considered for placement on the CWA section 303(d) List under section 3.1 and 3.6 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status.

Two lines of evidence are available in the administrative record to assess this pollutant. Three of nineteen water samples exhibited significant toxicity. The toxicity tests included survival of Ceriodaphnia dubia, survival of Pimephales promelas, and total cell count of Selenastrum capricornutum. One of six sediment samples tested with Hyalella azteca exhibited significant toxicity.

Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification in favor of placing this water segment-pollutant combination on the CWA section 303(d) List.

This conclusion is based on the staff findings that:
1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy.
2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy.
3. Three of nineteen water samples exhibited significant toxicity and this exceeds the allowable frequency listed in Table 3.1 of the Listing Policy.
4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should be placed on the section 303(d) list because applicable water quality standards are exceeded and a pollutant contributes to or causes the problem.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.
 
 
Line of Evidence (LOE) for Decision ID 94813, Toxicity
Region 5     
Mustang Creek (Merced County)
 
LOE ID: 23129
 
Pollutant: Toxicity
LOE Subgroup: Toxicity
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
Aquatic Life Use: Warm Freshwater Habitat
 
Number of Samples: 3
Number of Exceedances: 0
 
Data and Information Type: TOXICITY TESTING
Data Used to Assess Water Quality: Zero of the 3 samples tested with Ceriodaphnia dubia were toxic and violated the narrative toxicity objective.
Data Reference: Revised Draft of the 2007 Review of the Monitoring Data for the Irrigated Lands Regulatory Conditional Waiver Program
  Monitoring and Reporting Program, Order Nos. R5-2003-0826, R5-2005-0833, and R5-2008-0005 for Coalition Groups Under Resolution No. R5-2003-0105, Conditional Waiver of Waste Discharge Requirements for Discharges From Irrigated Lands Within the Central Valley Region
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that produce detrimental physiological responses in human, plant, animal, or aquatic life. This objective applies regardless of whether the toxicity is caused by a single substance or the interactive effect of multiple substances. (CVRWQCB, 2007)
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: Statistically significant difference from control using a t-test with 4-day acute-style toxicity tests.
Guideline Reference: Methods for Measuring the Acute Toxicity of Effluents and Receiving Waters to Freshwater and Marine Organisms, Fifth Edition. U.S. Environmental Protection Agency Office of Water, Washington, DC EPA-821-R-02-012
 
Spatial Representation: Sample was collected from Mustang Creek at East Avenue.
Temporal Representation: Samples were collected from May 2006 to August 2006.
Environmental Conditions:
QAPP Information: Data quality: Excellent. Monitoring was conducted in accordance with Central Valley Water Board Monitoring and Reporting Program (order number R5-2003-0826) requirements (CVRWQCB, 2003)
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 94813, Toxicity
Region 5     
Mustang Creek (Merced County)
 
LOE ID: 59148
 
Pollutant: Toxicity
LOE Subgroup: Toxicity
Matrix: Sediment
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 6
Number of Exceedances: 1
 
Data and Information Type: TOXICITY TESTING
Data Used to Assess Water Quality: Six samples were collected to evaluate sediment toxicity. One of the samples exhibited significant toxicity. The toxicity tests included survival of Hyalella azteca. One sample can have multiple toxicity test results but will be counted only once. One sample is defined as being collected on the same day at the same location with the same lab sample id (if provided).
Data Reference: Data for Various Pollutants in East San Joaquin, 2004-2009.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in, human, plant, animal, or aquatic life. Region 5 Basin Plan.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: Toxicity is defined as a statistically significant effect in the sample exposure compared to the control using EPA-recommended hypothesis testing. For SWAMP data exceedances are counted using the significant effect code: S equals significant, SG equals significantly greater and SL equals significantly lower. If a sample has any one of these codes, it will be considered an exceedance.
Guideline Reference: Methods for Measuring the Toxicity and Bioaccumulation of Sediment-associated Contaminants with Freshwater Invertebrates, Second Edition. U.S. Environmental Protection Agency Office of Research and Development, Duluth, MI , U.S. Environmental Protection Agency Office of Water, Washington, DC EPA-600/R-99/064
 
Spatial Representation: The samples were collected at Mustang Creek at East Ave.
Temporal Representation: The samples were collected from August 2006 to March 2010.
Environmental Conditions:
QAPP Information: Data was collected under the Quality Assurance Project Plan For Monitoring By The East San Joaquin Water Quality Coalition.
QAPP Information Reference(s): Quality Assurance Project Plan by the East San Joaquin Water Quality Coalition, Revision 1.0.
 
Line of Evidence (LOE) for Decision ID 94813, Toxicity
Region 5     
Mustang Creek (Merced County)
 
LOE ID: 68021
 
Pollutant: Toxicity
LOE Subgroup: Toxicity
Matrix: Water
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 19
Number of Exceedances: 3
 
Data and Information Type: TOXICITY TESTING
Data Used to Assess Water Quality: Nineteen samples were collected to evaluate water toxicity. Three of the samples exhibited significant toxicity(Ceriodaphnia dubia, 1/24/08, 1/30/08, and Selenastrum capricornutum, 2/26/08). The toxicity tests included survival of Ceriodaphnia dubia, survival of Pimephales promelas, and total cell count of Selenastrum capricornutum. One sample can have multiple toxicity test results but will be counted only once.
Data Reference: Data for Various Pollutants in East San Joaquin, 2004-2009.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in, human, plant, animal, or aquatic life. Region 5 Basin Plan.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: Toxicity is defined as a statistically significant effect in the sample exposure compared to the control using EPA-recommended hypothesis testing. For SWAMP data exceedances are counted with the significant effect code SL. SL is defined as the result being significant compared to the negative control based on a statistical test, less than stated the alpha level, AND less than the evaluation threshold. This data set reports a simple pass/fail (Yes/NO) code to report toxicity that is equivalent to the SWAMP SL code.
Guideline Reference: Short-term Methods for Estimating the Chronic Toxicity of Effluents and Receiving Waters to Freshwater Organisms. Fourth Edition. Office of Water, U.S. Environmental Protection Agency. Washington, D.C. EPA-821-R-02-013
 
Spatial Representation: The samples were collected at Mustang Creek at East Ave.
Temporal Representation: The samples were collected from May 2006 to April 2010.
Environmental Conditions:
QAPP Information: Data was collected under the Quality Assurance Project Plan For Monitoring By The East San Joaquin Water Quality Coalition.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 94813, Toxicity
Region 5     
Mustang Creek (Merced County)
 
LOE ID: 23148
 
Pollutant: Toxicity
LOE Subgroup: Toxicity
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
Aquatic Life Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: TOXICITY TESTING
Data Used to Assess Water Quality: Only one sample tested with Hyalella azteca survival.
Data Reference: Revised Draft of the 2007 Review of the Monitoring Data for the Irrigated Lands Regulatory Conditional Waiver Program
  Monitoring and Reporting Program, Order Nos. R5-2003-0826, R5-2005-0833, and R5-2008-0005 for Coalition Groups Under Resolution No. R5-2003-0105, Conditional Waiver of Waste Discharge Requirements for Discharges From Irrigated Lands Within the Central Valley Region
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that produce detrimental physiological responses in human, plant, animal, or aquatic life. This objective applies regardless of whether the toxicity is caused by a single substance or the interactive effect of multiple substances. (CVRWQCB, 2007)
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: Statistically significant difference from control using a t-test with 10-day Hyalella azteca sediment toxicity tests.
Guideline Reference: Methods for Measuring the Toxicity and Bioaccumulation of Sediment-associated Contaminants with Freshwater Invertebrates, Second Edition. U.S. Environmental Protection Agency Office of Research and Development, Duluth, MI , U.S. Environmental Protection Agency Office of Water, Washington, DC EPA-600/R-99/064
 
Spatial Representation: Sample was collected from Mustang Creek at East Avenue.
Temporal Representation: Sample was collected on August 10, 2006.
Environmental Conditions:
QAPP Information: Data quality: Fair. Monitoring was conducted in accordance with Central Valley Water Board Monitoring and Reporting Program (order number R5-2003-0826) requirements (CVRWQCB, 2003)
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 94813, Toxicity
Region 5     
Mustang Creek (Merced County)
 
LOE ID: 23150
 
Pollutant: Toxicity
LOE Subgroup: Toxicity
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
Aquatic Life Use: Warm Freshwater Habitat
 
Number of Samples: 2
Number of Exceedances: 0
 
Data and Information Type: TOXICITY TESTING
Data Used to Assess Water Quality: Zero of 2 samples tested with Selenastrum capricornutum were toxic and violated the narrative toxicity objective.
Data Reference: Revised Draft of the 2007 Review of the Monitoring Data for the Irrigated Lands Regulatory Conditional Waiver Program
  Monitoring and Reporting Program, Order Nos. R5-2003-0826, R5-2005-0833, and R5-2008-0005 for Coalition Groups Under Resolution No. R5-2003-0105, Conditional Waiver of Waste Discharge Requirements for Discharges From Irrigated Lands Within the Central Valley Region
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that produce detrimental physiological responses in human, plant, animal, or aquatic life. This objective applies regardless of whether the toxicity is caused by a single substance or the interactive effect of multiple substances. (CVRWQCB, 2007)
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: Statistically significant difference from control using a t-test with 4-day chronic-style toxicity tests.
Guideline Reference: Short-term Methods for Estimating the Chronic Toxicity of Effluents and Receiving Waters to Freshwater and Marine Organisms, Fourth Edition. U.S. Environmental Protection Agency Office of Water, Washington, DC EPA-821-R-02-013
 
Spatial Representation: Sample was collected from Mustang Creek at East Avenue.
Temporal Representation: Samples were collected from May 2006 to August 2006.
Environmental Conditions:
QAPP Information: Data quality: Excellent. Monitoring was conducted in accordance with Central Valley Water Board Monitoring and Reporting Program (order number R5-2003-0826) requirements (CVRWQCB, 2003)
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 94813, Toxicity
Region 5     
Mustang Creek (Merced County)
 
LOE ID: 23149
 
Pollutant: Toxicity
LOE Subgroup: Toxicity
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
Aquatic Life Use: Warm Freshwater Habitat
 
Number of Samples: 3
Number of Exceedances: 0
 
Data and Information Type: TOXICITY TESTING
Data Used to Assess Water Quality: Zero of the 3 samples tested with Pimephales promelas were toxic and violated the narrative toxicity objective.
Data Reference: Revised Draft of the 2007 Review of the Monitoring Data for the Irrigated Lands Regulatory Conditional Waiver Program
  Monitoring and Reporting Program, Order Nos. R5-2003-0826, R5-2005-0833, and R5-2008-0005 for Coalition Groups Under Resolution No. R5-2003-0105, Conditional Waiver of Waste Discharge Requirements for Discharges From Irrigated Lands Within the Central Valley Region
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that produce detrimental physiological responses in human, plant, animal, or aquatic life. This objective applies regardless of whether the toxicity is caused by a single substance or the interactive effect of multiple substances. (CVRWQCB, 2007)
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: Statistically significant difference from control using a t-test with 4-day acute-style toxicity tests.
Guideline Reference: Methods for Measuring the Acute Toxicity of Effluents and Receiving Waters to Freshwater and Marine Organisms, Fifth Edition. U.S. Environmental Protection Agency Office of Water, Washington, DC EPA-821-R-02-012
 
Spatial Representation: Sample was collected from Mustang Creek at East Avenue.
Temporal Representation: Samples were collected from May 2006 to August 2006.
Environmental Conditions:
QAPP Information: Data quality: Excellent. Monitoring was conducted in accordance with Central Valley Water Board Monitoring and Reporting Program (order number R5-2003-0826) requirements (CVRWQCB, 2003)
QAPP Information Reference(s):