Final California 2014 and 2016 Integrated Report (303(d) List/305(b) Report)

Supporting Information

Regional Board 1 - North Coast Region

Water Body Name: Cape Mendocino HU, Mattole River HA, Mattole River Watershed
Water Body ID: CAR1123007219980708151559
Water Body Type: River & Stream
 
DECISION ID
40543
Region 1     
Cape Mendocino HU, Mattole River HA, Mattole River Watershed
 
Pollutant: Chloride
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)(2012)
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. Under Section 3.2, a single line of evidence is necessary to assess listing status. One line of evidence is available to assess protection of the municipal and domestic supply (MUN) beneficial use. It should be noted that no new data were assessed this Integrated Report cycle, however the use rating and decision language was edit to reflect that there were an insufficient number of samples available to determine with the power and confidence of the Listing Policy if the MUN beneficial use is being protected.

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 (i.e., sufficient justification to not 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 exceed the objective, however this sample size is insufficient to determine with the power and confidence of the Listing Policy if standards are not met, as a minimum of either (1) 26 samples, or (2) greater than or equal to 5 exceedances of the objective with less than 26 samples is needed for application of 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 region was not assessed this cycle. All decisions have been carried over from the previous cycle and remain the same.
 
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 40543, Chloride
Region 1     
Cape Mendocino HU, Mattole River HA, Mattole River Watershed
 
LOE ID: 25435
 
Pollutant: Chloride
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Not Recorded
 
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: None of the 8 chloride samples collected in the Mattole River exceed the evaluation guideline. The samples were collected as part of the Surface Water Ambient Water Monitoring Program (SWAMP). The data are found in the SWAMP Summary Report for the North Coast Region for Years 2000-2006 (NCRWQCB 2008).
Data Reference: Surface Water Ambient Monitoring Program (SWAMP). Summary Report for the North Coast Region (RWQCB-1) for years 2000-2006. North Coast Regional Water Quality Control Board. March 2008
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Per the Basin Plan (NCRWQCB 2007): Waters shall not contain taste- or odor-producing substances in concentrations that impart undesirable tastes or odors to fish flesh or other edible products of aquatic origin, or that cause nuisance or adversely affect beneficial uses.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) - North Coast Region (Region 1)
 
Evaluation Guideline: Per 22 CCR 64449: The recommended Secondary Maximum Contaminant Level for chloride is 250 mg/L.
Guideline Reference: Title 22. Division 4. Chapter 15. Sections 64400 et seq. California Code of Regulations
 
Spatial Representation: Samples were collected from the Mattole River at 4 locations as follows: (1) at Ettersburg (SWAMP Station ID 112MATETT), (2) at Honeydew (SWAMP Station ID 112MATHON), (3) at Petrolia (SWAMP Station ID 112MATPET), and (4) from the North Fork Mattole River at Petrolia (SWAMP Station ID 112NFMATP). Samples were collected from well-mixed flows in glides or riffles.
Temporal Representation: Samples were collected as grab samples during 2 site visits to each of the 4 sites from April to May 2001.
Environmental Conditions: There are no known environmental conditions (e.g., seasonality, land use practices, fire events, storms, etc.) that are related to these data.
QAPP Information: Quality control was conducted in accordance with the SWAMP Quality Assurance Management Plan (SWAMP 2002).
QAPP Information Reference(s): Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)
 
 
DECISION ID
36467
Region 1     
Cape Mendocino HU, Mattole River HA, Mattole River Watershed
 
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)(2012)
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 3.1 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. None of the 8 lead 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 (i.e., sufficient justification to not 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) None of the 8 samples exceeded the lead objective, and this sample size is insufficient to determine with the power and confidence of the Listing Policy if standards are not met, as a minimum of either (A) 16 samples, or (B) greater than or equal 2 exceedances of the objective with less than 16 samples is needed for application of 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 region was not assessed this cycle. All decisions have been carried over from the previous cycle and remain the same.
 
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 36467, Lead
Region 1     
Cape Mendocino HU, Mattole River HA, Mattole River Watershed
 
LOE ID: 21531
 
Pollutant: Lead
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
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: None of the 8 lead samples collected in the Mattole River exceed the objectives. There were 2 samples collected at each of the 4 sites. The samples were collected as part of the Surface Water Ambient Water Monitoring Program (SWAMP). The data are found in the SWAMP Summary Report for the North Coast Region for Years 2000-2006 (NCRWQCB 2008).
Data Reference: Surface Water Ambient Monitoring Program (SWAMP). Summary Report for the North Coast Region (RWQCB-1) for years 2000-2006. North Coast Regional Water Quality Control Board. March 2008
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Per the Basin Plan (NCRWQCB 2007): Lead objective is 0.05 mg/L.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) - North Coast Region (Region 1)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Samples were collected from the Mattole River at 4 locations as follows: (1) at Ettersburg (SWAMP Station ID 112MATETT), (2) at Honeydew (SWAMP Station ID 112MATHON), (3) at Petrolia (SWAMP Station ID 112MATPET), and (4) from the North Fork Mattole River at Petrolia (SWAMP Station ID 112NFMATP). Samples were collected from well-mixed flows in glides or riffles.
Temporal Representation: Samples were collected as grab samples during 2 site visits to each of the 4 sites from April to May 2001.
Environmental Conditions: There are no known environmental conditions (e.g., seasonality, land use practices, fire events, storms, etc.) that are related to these data.
QAPP Information: Quality control was conducted in accordance with the SWAMP Quality Assurance Management Plan (SWAMP 2002).
QAPP Information Reference(s): Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)
 
 
DECISION ID
42450
Region 1     
Cape Mendocino HU, Mattole River HA, Mattole River Watershed
 
Pollutant: Nitrogen, ammonia (Total Ammonia)
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)(2012)
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 3.1 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. No new data were assessed during the current Integrated Report cycle, however it should be noted that the use rating and decision language have been altered to reflect that there are insufficient data available to make a listing determination. Also, the pollutant name was changed from "Ammonia as Nitrogen" to "Nitrogen, ammonia (Total Ammonia)".

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 (i.e., sufficient justification to not 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 8 samples exceeded the evaluation guideline, and this sample size is insufficient to determine with the power and confidence of the Listing Policy if standards are not met, as a minimum of either (A) 16 samples, or (B) greater than or equal 2 exceedances of the objective with less than 16 samples is needed for application of 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 region was not assessed this cycle. All decisions have been carried over from the previous cycle and remain the same.
 
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 42450, Nitrogen, ammonia (Total Ammonia)
Region 1     
Cape Mendocino HU, Mattole River HA, Mattole River Watershed
 
LOE ID: 26319
 
Pollutant: Ammonia as Nitrogen
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
Aquatic Life Use: Fish Migration | Fish Spawning | Freshwater Replenishment | Preservation of Rare & Endangered Species | Wildlife Habitat
 
Number of Samples: 8
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: None of the 8 ammonia as nitrogen samples collected from the Mattole River exceed the objective. The samples were collected as part of the Surface Water Ambient Water Monitoring Program (SWAMP). The data are found in the SWAMP Summary Report for the North Coast Region for Years 2000-2006 (NCRWQCB 2008).
Data Reference: Surface Water Ambient Monitoring Program (SWAMP). Summary Report for the North Coast Region (RWQCB-1) for years 2000-2006. North Coast Regional Water Quality Control Board. March 2008
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Per the Basin Plan (NCRWQCB 2007): 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.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) - North Coast Region (Region 1)
 
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: National Recommended Water Quality Criteria. United States Environmental Protection Agency. Office of Water. Office of Science and Technology
 
Spatial Representation: Samples were collected from the Mattole River at 4 locations as follows: (1) at Ettersburg (SWAMP Station ID 112MATETT), (2) at Honeydew (SWAMP Station ID 112MATHON), (3) at Petrolia (SWAMP Station ID 112MATPET), and (4) from the North Fork Mattole River at Petrolia (SWAMP Station ID 112NFMATP). Samples were collected from well-mixed flows in glides or riffles.
Temporal Representation: Samples were collected as grab samples during 2 site visits to each of the 4 sites from April to May 2001.
Environmental Conditions: There are no known environmental conditions (e.g., seasonality, land use practices, fire events, storms, etc.) that are related to these data.
QAPP Information: Quality control was conducted in accordance with the SWAMP Quality Assurance Management Plan (Puckett 2002).
QAPP Information Reference(s): Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)
 
 
DECISION ID
40496
Region 1     
Cape Mendocino HU, Mattole River HA, Mattole River Watershed
 
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)(2012)
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. Under this section 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.

It should be noted that in the Decision for this water body-pollutant pair from the 2010 Integrated Report cycle a Use Rating of "Fully Supporting" was selected, when it should have been "Insufficient Information" for the reason stated in (3) below.

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) Two of eight samples exceed the objective and this sample size is insufficient to determine with the power and confidence of the Listing Policy if standards are not met. A minimum of either (a) 26 samples, or (b) greater than or equal 5 exceedances of the MUN objective with less than 26 samples is needed for application of 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 region was not assessed this cycle. All decisions have been carried over from the previous cycle and remain the same.
 
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 40496, Specific Conductivity
Region 1     
Cape Mendocino HU, Mattole River HA, Mattole River Watershed
 
LOE ID: 21304
 
Pollutant: Specific Conductivity
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: Two of the 8 specific conductivity grab samples collected from the Mattole River exceed the objective. The samples were collected as part of the Surface Water Ambient Water Monitoring Program (SWAMP). The data are found in the SWAMP Summary Report for the North Coast Region for Years 2000-2006 (NCRWQCB 2008).
Data Reference: Surface Water Ambient Monitoring Program (SWAMP). Summary Report for the North Coast Region (RWQCB-1) for years 2000-2006. North Coast Regional Water Quality Control Board. March 2008
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Per the Basin Plan (NCRWQCB 2007): The 90% upper limit specific conductance objective at 77 F is 300 micromhos (or mS/cm2). The 50% upper limit specific conductance objective at 77 F is 170 micromhos (or mS/cm2). The 90% and 50% upper limits represent the 90/50 percentile values for a calendar year. 90% or 50% or more of the values must be less than or equal to the upper limit.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) - North Coast Region (Region 1)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Samples were collected from the Mattole River at 4 locations as follows: (1) at Ettersburg (SWAMP Station ID 112MATETT), (2) at Honeydew (SWAMP Station ID 112MATHON), (3) at Petrolia (SWAMP Station ID 112MATPET), and (4) from the North Fork Mattole River at Petrolia (SWAMP Station ID 112NFMATP). Samples were collected from well-mixed flows in glides or riffles.
Temporal Representation: Samples were collected as grab samples during 2 site visits to each of the 4 sites from April to May 2001.
Environmental Conditions: There are no known environmental conditions (e.g., seasonality, land use practices, fire events, storms, etc.) that are related to these data.
QAPP Information: Quality control was conducted in accordance with the SWAMP Quality Assurance Management Plan (Puckett 2002).
QAPP Information Reference(s): Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)
 
 
DECISION ID
38911
Region 1     
Cape Mendocino HU, Mattole River HA, Mattole River Watershed
 
Pollutant: Sulfates
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)(2012)
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. Under Section 3.2, a single line of evidence is necessary to assess listing status. One line of evidence is available to assess protection of the municipal and domestic supply (MUN) beneficial use. It should be noted that no new data were assessed this Integrated Report cycle, however the use rating and decision language was edit to reflect that there were an insufficient number of samples available to determine with the power and confidence of the Listing Policy if the MUN beneficial use is being protected.

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 (i.e., sufficient justification to not 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 8 samples exceed the objective, however this sample size is insufficient to determine with the power and confidence of the Listing Policy if standards are not met, as a minimum of either (1) 26 samples, or (2) greater than or equal to 5 exceedances of the objective with less than 26 samples is needed for application of 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 region was not assessed this cycle. All decisions have been carried over from the previous cycle and remain the same.
 
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 38911, Sulfates
Region 1     
Cape Mendocino HU, Mattole River HA, Mattole River Watershed
 
LOE ID: 25544
 
Pollutant: Sulfates
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Not Recorded
 
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: None of the 8 sulfate samples collected in the Mattole River exceed the evaluation guideline. The samples were collected as part of the Surface Water Ambient Water Monitoring Program (SWAMP). The data are found in the 5-Year Monitoring Report (NCRWQCB 2008).
Data Reference: Surface Water Ambient Monitoring Program (SWAMP). Summary Report for the North Coast Region (RWQCB-1) for years 2000-2006. North Coast Regional Water Quality Control Board. March 2008
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Per the Basin Plan (NCRWQCB 2007, p. 3-3.00): Waters shall not contain taste- or odor-producing substances in concentrations that impart undesirable tastes or odors to fish flesh or other edible products of aquatic origin, or that cause nuisance or adversely affect beneficial uses.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) - North Coast Region (Region 1)
 
Evaluation Guideline: Per 22 CCR 64449 (Table 64449-B): The recommended secondary maximum contaminant level for sulfate is 250 mg/L.
Guideline Reference: Title 22. Division 4. Chapter 15. Sections 64400 et seq. California Code of Regulations
 
Spatial Representation: Samples were collected from the Mattole River at 4 locations as follows: (1) at Ettersburg (SWAMP Station ID 112MATETT), (2) at Honeydew (SWAMP Station ID 112MATHON), (3) at Petrolia (SWAMP Station ID 112MATPET), and (4) from the North Fork Mattole River at Petrolia (SWAMP Station ID 112NFMATP). Samples were collected from well-mixed flows in glides or riffles.
Temporal Representation: Samples were collected as grab samples during 2 site visits to each of the 4 sites from April to May 2001.
Environmental Conditions: There are no known environmental conditions (e.g., seasonality, land use practices, fire events, storms, etc.) that are related to these data.
QAPP Information: Quality control was conducted in accordance with the SWAMP Quality Assurance Management Plan (SWAMP 2002).
QAPP Information Reference(s): Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)
 
 
DECISION ID
35148
Region 1     
Cape Mendocino HU, Mattole River HA, Mattole River Watershed
 
Pollutant: Sedimentation/Siltation
Final Listing Decision: List on 303(d) list (being addressed by USEPA approved TMDL)
Last Listing Cycle's Final Listing Decision: List on 303(d) list (being addressed by USEPA approved TMDL)(2012)
Revision Status Original
Sources: Flow Alteration/Regulation/Modification | Grazing-Related Sources | Logging Road Construction/Maintenance | Natural Sources | Removal of Riparian Vegetation | Road Construction | Silviculture
TMDL Name: Mattole Sediment
TMDL Project Code: 100
Date TMDL Approved by USEPA: 12/30/2003
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: Regional Water Board Conclusion:

This pollutant was considered for placement on the section 303(d) List in a previous Integrated Report cycle.

No new information was reviewed for this current Integrated Report cycle. Therefore, the previous conclusion remains unchanged, and is as follows:

This pollutant is being considered for listing under Section 2.2 of the Listing Policy. Under this section of the Policy, a minimum of one line of evidence is needed to assess listing status.

The Mattole River Total Maximum Daily Loads for Sediment and Temperature was approved by the USEPA on December 30, 2004.

Based on the readily available information, the weight of evidence indicates that there is sufficient justification in favor of placing this water segment-pollutant combination in the Water Quality Limited Segments Being Addressed portion of the Section 303(d) List.
 
Regional Board Decision Recommendation: This region was not assessed this cycle. All decisions have been carried over from the previous cycle and remain the same.
 
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 35148, Sedimentation/Siltation
Region 1     
Cape Mendocino HU, Mattole River HA, Mattole River Watershed
 
LOE ID: 1683
 
Pollutant: Sedimentation/Siltation
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 0
Number of Exceedances: 0
 
Data and Information Type: Not Specified
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 2006 303(d)
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion:
Objective/Criterion Reference:
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation:
Temporal Representation:
Environmental Conditions:
QAPP Information: QA Info Missing
QAPP Information Reference(s):
 
 
DECISION ID
32446
Region 1     
Cape Mendocino HU, Mattole River HA, Mattole River Watershed
 
Pollutant: Temperature, water
Final Listing Decision: List on 303(d) list (being addressed by USEPA approved TMDL)
Last Listing Cycle's Final Listing Decision: List on 303(d) list (being addressed by USEPA approved TMDL)(2012)
Revision Status Original
Sources: Flow Alteration/Regulation/Modification | Removal of Riparian Vegetation
TMDL Name: Mattole Temperature
TMDL Project Code: 101
Date TMDL Approved by USEPA: 12/30/2003
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: Regional Water Board Conclusion:

This pollutant was considered for placement on the section 303(d) List in a previous Integrated Report cycle.

No new information was reviewed for this current Integrated Report cycle. Therefore, the previous conclusion remains unchanged, and is as follows:

This pollutant is being considered for listing under Section 2.2 of the Listing Policy. Under this section of the Policy, a minimum of one line of evidence is needed to assess listing status.

The Mattole River Total Maximum Daily Loads for Sediment and Temperature was approved by the USEPA on December 30, 2004.

Based on the readily available information, the weight of evidence indicates that there is sufficient justification in favor of placing this water segment-pollutant combination in the Water Quality Limited Segments Being Addressed portion of the Section 303(d) List.
 
Regional Board Decision Recommendation: This region was not assessed this cycle. All decisions have been carried over from the previous cycle and remain the same.
 
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 32446, Temperature, water
Region 1     
Cape Mendocino HU, Mattole River HA, Mattole River Watershed
 
LOE ID: 3659
 
Pollutant: Temperature, water
LOE Subgroup: Pollutant-Water
Matrix: Not Specified
Fraction: None
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 0
Number of Exceedances: 0
 
Data and Information Type: Not Specified
Data Used to Assess Water Quality: 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:
Objective/Criterion Reference:
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Unknown
Temporal Representation: Unknown
Environmental Conditions: Unknown
QAPP Information: Unknown
QAPP Information Reference(s):