Final California 2010 Integrated Report (303(d) List/305(b) Report)

Supporting Information

Regional Board 9 - San Diego Region

Water Body Name: San Juan Creek
Water Body ID: CAR9012000020011025103828
Water Body Type: River & Stream
 
DECISION ID
17907
Region 9     
San Juan Creek
 
Pollutant: Benthic Community Effects
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: Benthic Community Effects is being considered for placement on the section 303(d) list under sections 3.9 and 3.2 of the Listing Policy. Under section 3.9, an additional line of evidence associating the Benthic Community Effects with a water or sediment concentration of pollutants is necessary to assess listing status.

One line of evidence is available in the administrative record to assess this indicator. 8 of 8 samples exceeded the water quality objective.

Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing Benthic Community Effects in this water segment on the section 303(d) list in the Water Quality Limited Segments category. 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. 8 of 8 samples exceeded the Index of Biological Integrity (IBI) value of "poor" water quality for this area and this exceeds the allowable frequency listed in Table 3.2 of the Listing Policy, however as required under section 3.9 of the Listing Policy, pollutant(s) could not be directly associated with the Benthic Community Effects.
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 because it cannot be determined if 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.
 
USEPA Action (if applicable):
 
 
Line of Evidence (LOE) for Decision ID 17907, Benthic Community Effects
Region 9     
San Juan Creek
 
LOE ID: 26443
 
Pollutant: Benthic Community Effects
LOE Subgroup: Adverse Biological Responses
Matrix: Water
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 8
Number of Exceedances: 8
 
Data and Information Type: Benthic macroinvertebrate surveys
Data Used to Assess Water Quality: Eight samples of IBI data were taken from September 1998 to 2007 at one sampling site. Of the total number of samples, all eight of the samples exceeded the IBI impairment threshold.
Data Reference: Fish and Game IBI Data
  Southern California Postfire Study. Index of Biotic Integrity. 2007
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: From the San Diego Basin Plan the objective is: 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. Compliance with this objective will be determined by use of indicator organisms, analyses of species diversity, population density, growth anomalies, bioassays of appropriate duration, or other appropriate methods as specified by the Regional Board. (SDRWQCB, 1995)
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline: The Index of Biological Integrity (IBI) is an analytical tool that can be used to assess the biological and physical condition of streams and rivers within a zero to one hundred scoring range: Very Poor 0-19, Poor 20-39, Fair 40-59, Good 60- 79, Very Good 80-100. The IBI score of 39 was set as an impairment threshold because it is a statistical criterion of two standard deviations below the mean reference site score which defines the boundary between 'fair' and 'poor' IBI creek conditions. (Ode, p. 9)
Guideline Reference: A Quantitative Tool for Assessing the Integrity of Southern Coastal California Streams. Environmental Management. Volume 35, number 1 (2005): pp. 1-13
 
Spatial Representation: Samples were collected at one site: 901SJC74x on San Juan Creek.
Temporal Representation: Sampling occurred during eight events over a ten year period from September 1998 to 2007.
Environmental Conditions:
QAPP Information: Quality Control for collection and identification was conducted in accordance with the Quality Assurance Project Plan for the California Stream Bioassessment Procedure and the State of California, California Monitoring an Assessment Program: "CMAP", Quality Assurance Project Plan.
QAPP Information Reference(s): State of California, California Monitoring and Assessment Program: "CMAP".
  Quality Assurance Project Plan for the California Stream Bioassessment Procedure
  The San Diego Stream Team Quality Assurance Project Plan
 
 
DECISION ID
17061
Region 9     
San Juan Creek
 
Pollutant: Diazinon
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: This pollutant is being considered for placement on the 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.

Two lines of evidence are available in the administrative record to assess this pollutant. One of the 26 samples exceed the water quality 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 section 303(d) list in the Water Quality Limited Segments category.

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. One of 26 samples exceeded the diazinon water quality objective and this does not exceed 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.
 
USEPA Action (if applicable):
 
 
Line of Evidence (LOE) for Decision ID 17061, Diazinon
Region 9     
San Juan Creek
 
LOE ID: 21253
 
Pollutant: Diazinon
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 5
Number of Exceedances: 0
 
Data and Information Type: Fixed station physical/chemical monitoring (conventional pollutants only)
Data Used to Assess Water Quality: There were no exceedances in the five samples collected according to results in the Unified Annual Progress Report Program Effectiveness Assessment, 2007. Samples were taken on five dates: October 10, 2003; May 13, 2004; October 14, 2004; May 18, 2005; December 14, 2005.
Data Reference: Program Effectiveness Assessment Section of the Unified Annual Progress Report for the period of time 2001-2007
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall be present in the water column, sediments or biota at concentration(s) that adversely affect beneficial uses. Pesticides shall not be present at levels which will bioaccumulate in aquatic organisms to levels which are harmful to human health, wildlife or aquatic organisms (RWQCB, 2007).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline: The one-hour average concentration of diazinon should not exceed 0.17 µg/L more than once every three years on the average (acute criterion) and the four-day average concentration of diazinon should not exceed 0.17 µg/L more than once every three years on the average (chronic criterion). (U.S. EPA, 2006)
Guideline Reference: Fact Sheet: Final Recommended Aquatic Life Ambient Water Quality Criteria for Diazinon
 
Spatial Representation: Samples were collected from lower San Juan Creek at Camino Capistrano. Latitude/Longitude: 33.4978/ -117.6661.
Temporal Representation: Samples were taken on five dates: October 10, 2003; May 13, 2004; October 14, 2004; May 18, 2005; December 14, 2005.
Environmental Conditions:
QAPP Information: Quality assurance plan followed guidelines outlined by the County of Orange.
QAPP Information Reference(s): County of Orange. Quality Assurance/Quality Control Manual, February 2004 Bacteria specific
 
Line of Evidence (LOE) for Decision ID 17061, Diazinon
Region 9     
San Juan Creek
 
LOE ID: 21242
 
Pollutant: Diazinon
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 17
Number of Exceedances: 1
 
Data and Information Type: Fixed station physical/chemical monitoring (conventional pollutants only)
Data Used to Assess Water Quality: One of the 17 samples exceeded 0.17 µg/L.
Data Reference: California Stream Bioassesment Procedure: Protocol Brief for Biological and Physical/Habitat Assessment in Wadeable Streams
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall be present in the water column, sediments or biota at concentration(s) that adversely affect beneficial uses. Pesticides shall not be present at levels which will bioaccumulate in aquatic organisms to levels which are harmful to human health, wildlife or aquatic organisms (RWQCB, 2007).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline: The one-hour average concentration of diazinon should not exceed 0.17 µg/L more than once every three years on the average (acute criterion) and the four-day average concentration of diazinon should not exceed 0.17 µg/L more than once every three years on the average (chronic criterion). (U.S. EPA, 2006)
Guideline Reference: Fact Sheet: Final Recommended Aquatic Life Ambient Water Quality Criteria for Diazinon
 
Spatial Representation: Samples were collected from the lower San Juan Creek at Stonehill Drive. Latitude/Longitude: 33.4753/ -117.6790
Temporal Representation: Samples were taken on various dates starting April 8, 1999 to January 17, 2001.
Environmental Conditions:
QAPP Information: None available. Data submitted to the DPR’s Surface Water Database is subject to the document “Requirements for Inclusion of Monitoring Data in DPR’s Surface Water Database.”
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 17061, Diazinon
Region 9     
San Juan Creek
 
LOE ID: 21244
 
Pollutant: Diazinon
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 4
Number of Exceedances: 0
 
Data and Information Type: Fixed station physical/chemical monitoring (conventional pollutants only)
Data Used to Assess Water Quality: There were no exceedances in the data, the four samples taken have a mean of 0.036 µg/L. according to results in the Surface Water Ambient Monitoring Program, 2007.
Data Reference: Monitoring data for Region 9
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall be present in the water column, sediments or biota at concentration(s) that adversely affect beneficial uses. Pesticides shall not be present at levels which will bioaccumulate in aquatic organisms to levels which are harmful to human health, wildlife or aquatic organisms (RWQCB, 2007).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline: The one-hour average concentration of diazinon should not exceed 0.17 µg/L more than once every three years on the average (acute criterion) and the four-day average concentration of diazinon should not exceed 0.17 µg/L more than once every three years on the average (chronic criterion). (U.S. EPA, 2006)
Guideline Reference: Fact Sheet: Final Recommended Aquatic Life Ambient Water Quality Criteria for Diazinon
 
Spatial Representation: The four samples were collected in the lower San Juan Creek Station; Lat/Long: 33.4847/-117.6746.
Temporal Representation: This site was monitored in 2003.
Environmental Conditions:
QAPP Information: Quality control for the chemical analysis portion of this study was conducted in accordance with the California's Surface Water Ambient Monitoring Program.
QAPP Information Reference(s): 2002. Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. California Department of Fish and Game, Monterey, CA
 
 
DECISION ID
4716
Region 9     
San Juan Creek
 
Pollutant: Phosphorus
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)(2006)
Revision Status Revised
Sources: Unknown Nonpoint Source | Unknown Point Source | Urban Runoff/Storm Sewers
Expected TMDL Completion Date: 2021
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: This pollutant is being considered for placement on the 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.

Two lines of evidence are available in the administrative record to assess this pollutant. Ten of the samples exceed the water quality objective for phosphorus.

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 section 303(d) list in the Water Quality Limited Segments category.

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 23 samples exceeded the total phosphorus water quality objective and this exceeds 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: 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.
 
USEPA Action (if applicable): USEPA approved the listing of this water body as a water quality limited segment requiring a TMDL for this pollutant.
 
 
Line of Evidence (LOE) for Decision ID 4716, Phosphorus
Region 9     
San Juan Creek
 
LOE ID: 6814
 
Pollutant: Phosphorus
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 12
Number of Exceedances: 10
 
Data and Information Type: Fixed station physical/chemical monitoring (conventional pollutants only)
Data Used to Assess Water Quality: Ten of twelve flow-weighted event mean concentrations exceeded the water quality objective according to results in the Orange County Stormwater Program Annual Progress Reports from 2004-2007. Samples were collected during two to four storm events a year from 2002-2006.
Data Reference: Orange County Stormwater Program. 2004-2007. Unified Annual Progress Reports, Program Effectiveness Assessment (San Diego Region)
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Water bodies shall not contain biostimulatory substances in concentrations that promote aquatic growth to the extent that such growths cause nuisance or adversely affect beneficial uses (RWQCB, 2007).
The Water Quality Control Plan for the San Diego Basin (9) goal is 0.1 mg/L for phosphorus in streams and other flowing waters.
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline:
Guideline Reference: Water Quality Control Plan for the San Diego Basin
 
Spatial Representation: Samples were collected at the mass loading station at La Novia Avenue at 33.5020°, 117.6482°.
Temporal Representation: Samples were collected during two to four storm events a year from 2002-2006.
Environmental Conditions: Samples were collected during wet weather.
QAPP Information: QA/QC conducted according to Federal Regulations under requirements of a NPDES permit.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 4716, Phosphorus
Region 9     
San Juan Creek
 
LOE ID: 3006
 
Pollutant: Phosphorus
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Agricultural Supply
 
Number of Samples: 11
Number of Exceedances: 0
 
Data and Information Type: Not Specified
Data Used to Assess Water Quality: Data were collected by the USDA Forest Service in 1998. Eleven samples were collected. All were at or below the standard of 0.1 mg/L. (SWRCB, 2003).
Data Reference: Placeholder reference 2006 303(d)
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: From the Basin Plan: For inland surface waters, streams, and other flowing waters
and all beneficial uses, the WQO for total phosphorus is 0.1 mg/L. This appears to be the desired goal in order to prevent plant nuisance in streams and other flowing waters; not to be exceeded more than 10% of the time.
Objective/Criterion Reference: Placeholder reference 2006 303(d)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Samples were collected in San Juan Creek (Hot Springs/San Juan Drainage).
Temporal Representation: Samples were collected 6 times on 06/26/1998 from 9:55am-11:00am and 5 times on 10/30/1998 from 9:40am to 10:30am.
Environmental Conditions:
QAPP Information: Data used in 2002 assessment.
QAPP Information Reference(s):
 
 
DECISION ID
17062
Region 9     
San Juan Creek
 
Pollutant: Selenium
Final Listing Decision: List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: New Decision
Revision Status Revised
Sources: Unknown Nonpoint Source | Unknown Point Source | Urban Runoff/Storm Sewers
Expected TMDL Completion Date: 2021
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: This pollutant is being considered for placement on the 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. Two of the samples exceed the water quality objective for selenium.

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 section 303(d) list in the Water Quality Limited Segments category.

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 four samples exceed the selenium water quality objective 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.
 
USEPA Action (if applicable): USEPA approved the listing of this water body as a water quality limited segment requiring a TMDL for this pollutant.
 
 
Line of Evidence (LOE) for Decision ID 17062, Selenium
Region 9     
San Juan Creek
 
LOE ID: 9096
 
Pollutant: Selenium
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 4
Number of Exceedances: 2
 
Data and Information Type: Fixed station physical/chemical monitoring (conventional pollutants only)
Data Used to Assess Water Quality: Four water samples were collected at San Juan station 901SJSJC9 on October 2002, January 2003, April 2003, and May 2003. Two of the four samples showed excessive selenium concentrations according to results in California's Surface Water Ambient Monitoring Program.
Data Reference: Orange County Stormwater Program. 2004-2007. Unified Annual Progress Reports, Program Effectiveness Assessment (San Diego Region)
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: CTR Freshwater Chronic (CCC) 5 ug/L. (U.S. EPA, 2000).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline:
Guideline Reference: Water Quality Control Plan for the San Diego Basin
 
Spatial Representation: Water samples were collected at San Juan Creek station (901SJSJC9).
Temporal Representation: Samples for San Juan Creek were collected on October 2002, January 2003, April 2003, and May 2003.
Environmental Conditions:
QAPP Information: Quality control for the chemical analysis portion of this study was conducted in accordance with the California's Surface Water Ambient Monitoring Program.
QAPP Information Reference(s):
 
 
DECISION ID
17063
Region 9     
San Juan Creek
 
Pollutant: Total Nitrogen as N
Final Listing Decision: List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: New Decision
Revision Status Revised
Sources: Unknown Nonpoint Source | Unknown Point Source | Urban Runoff/Storm Sewers
Expected TMDL Completion Date: 2021
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: This pollutant is being considered for placement on the 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.

One line of evidence is available in the administrative record to assess this pollutant. Ten of the samples exceed the water quality objective for nitrogen.

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 section 303(d) list in the Water Quality Limited Segments category.

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 12 samples exceed the total nitrogen water quality objective and this exceeds 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: 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.
 
USEPA Action (if applicable): USEPA approved the listing of this water body as a water quality limited segment requiring a TMDL for this pollutant.
 
 
Line of Evidence (LOE) for Decision ID 17063, Total Nitrogen as N
Region 9     
San Juan Creek
 
LOE ID: 7759
 
Pollutant: Total Nitrogen as N
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 12
Number of Exceedances: 10
 
Data and Information Type: Fixed station physical/chemical monitoring (conventional pollutants only)
Data Used to Assess Water Quality: Ten of twelve flow-weighted event mean concentrations exceeded the water quality objective according to results in the Orange County Stormwater Program Annual Progress Report, 2004-2007. Samples were collected during two to four storm events a year from 2002-2006.
Data Reference: Orange County Stormwater Program. 2004-2007. Unified Annual Progress Reports, Program Effectiveness Assessment (San Diego Region)
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Water bodies shall not contain biostimulatory substances in concentrations that promote aquatic growth to the extent that such growths cause nuisance or adversely affect beneficial uses (RWQCB, 2007).
The Water Quality Control Plan for the San Diego Basin (9) states: “A desired goal in order to prevent plant nuisance in streams and other flowing waters appears to be 0.1 mg/L total P. These values are not to be exceeded more than 10% of the time unless studies of the specific water body in question clearly show that water quality objective changes are permissible and changes are approved by the Regional Board. Analogous threshold values have not been set for nitrogen compounds; however, natural ratios of nitrogen to phosphorus are to be determined by surveillance and monitoring and upheld. If data are lacking, a ratio of N:P = 10:1, on a weight to weight basis shall be used.” Since the goal for total phosphorus is 0.1 mg/L, then according to the ratio provided, the goal for total nitrogen is 1 mg/L.
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline:
Guideline Reference: Water Quality Control Plan for the San Diego Basin
 
Spatial Representation: Samples were collected at the mass loading station at La Novia Avenue at 33.5020°, 117.6482°.
Temporal Representation: Samples were collected during two to four storm events a year from 2002-2006.
Environmental Conditions: Samples were collected during wet weather.
QAPP Information: QA/QC conducted according to Federal Regulations under requirements of a NPDES permit.
QAPP Information Reference(s):
 
 
DECISION ID
17064
Region 9     
San Juan Creek
 
Pollutant: Toxicity
Final Listing Decision: List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: New Decision
Revision Status Revised
Sources: Unknown Nonpoint Source | Unknown Point Source | Urban Runoff/Storm Sewers
Expected TMDL Completion Date: 2021
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: This pollutant is being considered for placement on the section 303(d) list under section 3.6 of the Listing Policy.

Two lines of evidence are available in the administrative record to assess this pollutant. Four of the samples exceed the water quality objective for 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 section 303(d) list in the Water Quality Limited Segments category.

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. Four of 17 samples exceed the toxicity water quality objective 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.
 
USEPA Action (if applicable): USEPA approved the listing of this water body as a water quality limited segment requiring a TMDL for this pollutant.
 
 
Line of Evidence (LOE) for Decision ID 17064, Toxicity
Region 9     
San Juan Creek
 
LOE ID: 21401
 
Pollutant: Toxicity
LOE Subgroup: Toxicity
Matrix: Water
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 8
Number of Exceedances: 4
 
Data and Information Type: Ambient toxicity testing (chronic)
Data Used to Assess Water Quality: Eight samples were collected at San Juan Creek station 901SJSJC5 and 901SJSJC9 from October2002 to May 2003, they showed significant toxicity levels (SL) in the following test: Selenastrum algae growth test - Four of eight samples were toxic.

Ceriodaphnia dubia survival and reproduction: None of the samples were toxic.

Hyalella azteca: One of six samples were toxic. Two additional tests were not valid.
Data Reference: Monitoring data for Region 9
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: From the Basin Plan, all waters shall be free of toxic substances that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life.
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline: According to SWAMP, waters are considered toxic when samples show significant toxicity levels (SWAMP code ‘SL’) when compared to a negative control. Significant toxicity is determined when statistical tests result in an alpha of less than 5% and percent control values less than the evaluation threshold (EPA, 2002).
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: Water Toxicity Samples were collected at San Juan Creek stations 901SJSJC5 and 901SJSJC9
Temporal Representation: Water samples were collected on September 2002, November 2002, January 2003, April 2003, and May 2003.
Environmental Conditions:
QAPP Information: Quality control for the chemical analysis portion of this study was conducted in accordance with the California's Surface Water Ambient Monitoring Program.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 17064, Toxicity
Region 9     
San Juan Creek
 
LOE ID: 7758
 
Pollutant: Toxicity
LOE Subgroup: Toxicity
Matrix: Water
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 9
Number of Exceedances: 0
 
Data and Information Type: Ambient toxicity testing (chronic)
Data Used to Assess Water Quality: Selenastrum Algae Growth-
None of the nine samples exhibited NOEC’s less than 100%.

Ceriodaphnia dubia -Survival-
None of the nine samples exhibited NOEC’s less than 100%.

Ceriodaphnia dubia -Reproduction-
None of the nine samples collected exhibited NOEC’s less than 100%.

Hyalella azteca survival-
None of the nine samples exhibited LC50’s less than 100% according to results in the Orange County Storm Water Program Annual Progress Report, 2002 - 2007. Samples were collected from 2003 - 2005.
Data Reference: Orange County Stormwater Program. 2004-2007. Unified Annual Progress Reports, Program Effectiveness Assessment (San Diego Region)
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: From the Basin Plan, all waters shall be free of toxic substances that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life (RWQCB, 2007).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline: Samples were found to exhibit toxicity when the No Observed Effect Concentration (NOEC) or median lethal concentration (LC50) for any given species was estimated to be less than 100% of the test sample concentration.
Guideline Reference: Water Quality Control Plan for the San Diego Basin
 
Spatial Representation: Samples were collected at two locations in San Juan Creek. Samples were collected at the Highway 74 and between Camino Capistrano and Interstate 5.
Temporal Representation: Samples were collected from 2003-2005.
Environmental Conditions: Samples were collected during wet weather.
QAPP Information: QA/QC conducted according to the County of Orange's Quality Assurance Plan
.
QAPP Information Reference(s): County of Orange. Quality Assurance/Quality Control Manual, February 2004 Bacteria specific
 
 
DECISION ID
4776
Region 9     
San Juan Creek
 
Pollutant: Benthic-Macroinvertebrate Bioassessments
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)(2006)
Revision Status Original
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: This pollutant is being considered for listing under sections 2.1, 3.6, and 3.9 of the Listing Policy. Under section 3.6 a single line of evidence is necessary to assess listing status while under section 3.9, a minimum of two lines of evidence are needed to assess listing status.

Only one line of evidence are available in the administrative record to assess this pollutant. Based on section 3.9 and the information submitted it cannot be determined if a pollutant is likely to cause or contribute to the toxic effect.

Based on the readily available data and information, the weight of evidence indicates that there is not sufficient justification in favor of placing this water segment-pollutant combination on the section 303(d) list in the Water Quality Limited Segments category.
 
Regional Board Decision Recommendation: No new data were assessed for 2008. The decision has not changed.
 
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 exceeded.
 
USEPA Action (if applicable):
 
 
Line of Evidence (LOE) for Decision ID 4776, Benthic-Macroinvertebrate Bioassessments
Region 9     
San Juan Creek
 
LOE ID: 3008
 
Pollutant: Benthic-Macroinvertebrate Bioassessments
LOE Subgroup: Population/Community Degradation
Matrix: Not Specified
Fraction: None
 
Beneficial Use: Non-Contact Recreation
 
Number of Samples: 0
Number of Exceedances: 0
 
Data and Information Type: Benthic macroinvertebrate surveys
Data Used to Assess Water Quality: Data were collected for the San Diego Regional Water Quality Control Board 1999 Biological Assessment Annual Report. Physical habitat scores ranged from 106 to 125, relatively higher compared to other sampled waterbodies. BMI ranking scores were near average (1 below, one above, and one at) compared to other sampled waterbodies. (SWRCB, 2003).
Data Reference: Placeholder reference 2006 303(d)
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: No objective.
Objective/Criterion Reference: Placeholder reference 2006 303(d)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Samples were collected at in San Juan Creek, 5 riffles upstream of Highway 74 (SJC-74). Lat/Long coordinates are N33E31' 9.0"/W117E37' 25.4".
Temporal Representation: Samples were collected in September and November 1998 and May 1999.
Environmental Conditions:
QAPP Information: Data used in 2002 assessment.
QAPP Information Reference(s):
 
 
DECISION ID
4777
Region 9     
San Juan Creek
 
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)(2006)
Revision Status Original
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: This pollutant is being considered for placement on the section 303(d) list under section 3.2 of the Listing Policy.

One line of evidence is available in the administrative record to assess this pollutant. A single sample exceeds the water quality objective.

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

This conclusion is based on the staff findings that:
1. The data used does not satisfy the data quality requirements of section 6.1.4 of the Policy. QAQC information was not available.
2. The data used does not satisfy the data quantity requirements of section 6.1.5 of the Policy. Data was collected from one site, therefore it is not known if spatial representation is adequate.
3. One out of 11 samples exceeded the 6 - 8.5 pH Basin Plan water quality objective, and this does not exceed the allowable frequency 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: No new data were assessed for 2008. The decision has not changed.
 
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.
 
USEPA Action (if applicable):
 
 
Line of Evidence (LOE) for Decision ID 4777, pH
Region 9     
San Juan Creek
 
LOE ID: 3007
 
Pollutant: pH
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Agricultural Supply
 
Number of Samples: 11
Number of Exceedances: 1
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Data were collected by the USDA Forest Service in 1998. One of 11 samples were in exceedance. (SWRCB, 2003).
Data Reference: Placeholder reference 2006 303(d)
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: From the Basin Plan: For inland surface waters and all beneficial uses, the WQO for pH is 6.5 (minimum) and 8.5 (maximum).
Objective/Criterion Reference: Placeholder reference 2006 303(d)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Samples were collected at San Juan Creek (San Juan/Hot Springs Drainage).
Temporal Representation: Samples were collected 6 times on 06/26/1998 from 9:55am to 11:00am and 5 times on 10/30/1998 from 9:40am to 10:30am.
Environmental Conditions:
QAPP Information: Data used in 2002 assessment.
QAPP Information Reference(s):
 
 
DECISION ID
5343
Region 9     
San Juan Creek
 
Pollutant: DDE (Dichlorodiphenyldichloroethylene)
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)(2006)
Revision Status Original
Sources: Source Unknown
Expected TMDL Completion Date: 2019
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: This pollutant is being considered for placement on the 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. A sufficient number of samples exceed the California Toxic Rule: Human Health-FW (water & organisms) criterion of 0.00059 µg/L.

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 section 303(d) list in the Water Quality Limited Segments category.

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 4 samples exceeded the California Toxic Rule: Human Health-FW (water & organisms) criterion of 0.00059 µg/L 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: No new data were assessed for 2008. The decision has not changed.
 
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.
 
USEPA Action (if applicable): USEPA approved the listing of this water body as a water quality limited segment requiring a TMDL for this pollutant.
 
 
Line of Evidence (LOE) for Decision ID 5343, DDE (Dichlorodiphenyldichloroethylene)
Region 9     
San Juan Creek
 
LOE ID: 3009
 
Pollutant: DDE (Dichlorodiphenyldichloroethylene)
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Not Recorded
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 4
Number of Exceedances: 2
 
Data and Information Type: Not Specified
Data Used to Assess Water Quality: Two of 4 samples exceeded the CTR (SWAMP, 2004).
Data Reference: Placeholder reference 2006 303(d)
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: San Diego RWQCB Basin Plan: No individual pesticide or combination of pesticides shall be present in the water column, sediments, or biota at concentration(s) that adversely affect beneficial uses.

California Toxic Rule: Human Health-FW (water & organisms) .00059 µg/L.
Objective/Criterion Reference: Placeholder reference 2006 303(d)
 
Evaluation Guideline: California Toxic Rule: Human Health-FW (water & organisms) 0.00059 µg/L.
Guideline Reference: Placeholder reference 2006 303(d)
 
Spatial Representation: One station at San Juan Creek: 33.484429 -117.67577.
Temporal Representation: Four samples collected from October 2002 through May of 2003.
Environmental Conditions: San Juan Creek Watershed: 901.27.
QAPP Information: SWAMP Quality Assurance Plan.
QAPP Information Reference(s):
 
 
DECISION ID
5959
Region 9     
San Juan Creek
 
Pollutant: Indicator Bacteria
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)(2006)
Revision Status Original
Sources: Nonpoint Source | Point Source
Expected TMDL Completion Date: 2019
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: 303(d) listing decisions made prior to 2006 were not held in an assessment database. The Regional Boards will update this decision when new data and information become available and are assessed.
 
Regional Board Decision Recommendation: No new data were assessed for 2008. The decision has not changed.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: N/A
 
USEPA Action (if applicable): USEPA approved the listing of this water body as a water quality limited segment requiring a TMDL for this pollutant.
 
 
Line of Evidence (LOE) for Decision ID 5959, Indicator Bacteria
Region 9     
San Juan Creek
 
LOE ID: 4726
 
Pollutant: Indicator Bacteria
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Not Recorded
 
Beneficial Use: Water Contact Recreation
 
Number of Samples: 0
Number of Exceedances: 0
 
Data and Information Type: PATHOGEN MONITORING
Data Used to Assess Water Quality: Unspecified--This LOE is a placeholder to support a 303(d) listing decision made prior to 2006.
Data Reference: Placeholder reference pre-2006 303(d)
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Unspecified
Objective/Criterion Reference: Placeholder reference pre-2006 303(d)
 
Evaluation Guideline: Unspecified
Guideline Reference: Placeholder reference pre-2006 303(d)
 
Spatial Representation: Unspecified
Temporal Representation: Unspecified
Environmental Conditions: Unspecified
QAPP Information: Unspecified
QAPP Information Reference(s):