# Draft 2008 California 303(d)/305(b) Integrated Report

# Supporting Information

## Regional Board 5 - Central Valley Region

Water Body Name: | Willow Creek (Shasta County, below Greenhorn Mine to Clear Creek)
Water Body ID: | CAR5246301119980818110732
Water Body Type: | River & Stream

DECISION ID | 8649
Pollutant: | Escherichia coli (E. Coli)
Final Listing Decision: | List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: | New Decision
Revision Status | Revised
Sources: | Source Unknown
Expected TMDL Completion Date: | 2021
Impairment from Pollutant or Pollution: | Pollutant
Weight of Evidence: | "This pollutant is being considered for listing under sections 3.3 of the Listing Policy. Under section 3.3 a single line of evidence is necessary to assess listing status. Data is available from 2 lines of evidence for this pollutant. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification for placing this water segment-pollution combination on the section 303(d) list. The recommendation is based on staff findings that 16 of 37 available concentrations exceeded the USEPA E. Coli Guideline for Non-Contact Recreation and this does exceed the allowable frequency using Table 3.2 of the Listing Policy. The recommendation is also based on staff findings that 18 of 37 available concentrations exceeded the USEPA E. Coli Guideline for Water Contact Recreation and this does exceed the allowable frequency using Table 3.2 of the Listing Policy. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met."
RWQCB Board Decision / Staff 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.
SWRCB Board Decision / Staff Recommendation: |
USEPA Decision: |

Lines of Evidence (LOEs) for Decision ID 8649

LOE ID: | 7561
Pollutant: | Escherichia coli (E. Coli)
LOE Subgroup: | Pollutant-Water
Matrix: | Water
Fraction: | None
Beneficial Use: | Non-Contact Recreation
Number of Samples: | 37
Number of Exceedances: | 16
Data and Information Type: | Not Specified
Data Used to Asses Water Quality: | Sixteen of the 37 samples collected by the Surface Water Ambient Monitoring Program exceeded the evaluation objective for E.Coli Bacteria. The exceeded results are as follows: 7/13/2004 - a sample taken at Lower Willow Creek had a result of 461MPN/100 mL. 8/17/2004 - a sample taken at Lower Willow Creek had a result of 980MPN/100 mL. 9/14/2004 - a sample taken at Lower Willow Creek had a result of 687MPN/100 mL. 5/16/2005 - a sample taken at Lower Willow Creek had a result of >2420MPN/100 mL. 6/20/2005 - a sample taken at Lower Willow Creek had a result of 1200MPN/100 mL. 8/16/2005 - a sample taken at Lower Willow Creek had a result of >2420MPN/100 mL. 5/21/2004 - a sample taken at Middle Willow Creek had a result of 613MPN/100 mL. 6/18/2004 - a sample taken at Middle Willow Creek had a result of 1410MPN/100 mL. 7/21/2004 - a sample taken at Middle Willow Creek had a result of >=2420MPN/100 mL. 8/17/2004 - a sample taken at Middle Willow Creek had a result of 649MPN/100 mL. 8/17/2004 - a sample taken at Middle Willow Creek had a result of 816MPN/100 mL. 5/16/2005 - a sample taken at Middle Willow Creek had a result of >2420MPN/100 mL. 6/20/2005 - a sample taken at Middle Willow Creek had a result of 488MPN/100 mL. 7/18/2005 - a sample taken at Middle Willow Creek had a result of 921MPN/100 mL. 8/15/2005 - a sample taken at Middle Willow Creek had a result of 727MPN/100 mL. 1/19/2005 - a sample taken at Upper Willow Creek had a result of 613MPN/100 mL.
Data Reference: | SWAMP data entered by SWRCB into BDAT database
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. (CRWQCB, 2006)
Objective/Criterion Reference: | Central Valley Regional Water Quality Control Board. Water Quality Control Plan (Basin Plan) for the California Regional Water Quality Control Board - Central Valley Region
Evaluation Guideline: | E.Coli Bacteria levels should not exceed 409 MPN/100 mL in any single sample (USEPA E.Coli Guideline)
Guideline Reference: | Ambient Water Quality Criteria for Bacteria - 1986. EPA440/5-84-002
Spatial Representation: | Samples were collected at Lower Willow Creek. Samples were collected at Middle Willow Creek. Samples were collected at Upper Willow Creek.
Temporal Representation: | The samples were collected from May 21 2004 to Sep 19 2005
Environmental Conditions: |
QAPP Information: | Monitoring was conducted in accordance with the State Water Resources Control Board's Quality Assurance Program Plan for the State of California's Surface Water Ambient Monitoring Program.
QAPP Information Reference(s):
LOE ID: | 7534
Pollutant: | Escherichia coli (E. Coli)
LOE Subgroup: | Pollutant-Water
Matrix: | Water
Fraction: | None
Beneficial Use: | Water Contact Recreation
Number of Samples: | 37
Number of Exceedances: | 18
Data and Information Type: | Not Specified
Data Used to Asses Water Quality: | Eighteen of the 37 samples collected by the Surface Water Ambient Monitoring Program exceeded the evaluation objective for E.Coli Bacteria. The exceeded results are as follows: 6/18/2004 - a sample taken at Lower Willow Creek had a result of 276MPN/100 mL. 7/13/2004 - a sample taken at Lower Willow Creek had a result of 461MPN/100 mL. 8/17/2004 - a sample taken at Lower Willow Creek had a result of 980MPN/100 mL. 9/14/2004 - a sample taken at Lower Willow Creek had a result of 687MPN/100 mL. 5/16/2005 - a sample taken at Lower Willow Creek had a result of >2420MPN/100 mL. 6/20/2005 - a sample taken at Lower Willow Creek had a result of 1200MPN/100 mL. 7/18/2005 - a sample taken at Lower Willow Creek had a result of 387MPN/100 mL. 8/16/2005 - a sample taken at Lower Willow Creek had a result of >2420MPN/100 mL. 5/21/2004 - a sample taken at Middle Willow Creek had a result of 613MPN/100 mL. 6/18/2004 - a sample taken at Middle Willow Creek had a result of 1410MPN/100 mL. 7/21/2004 - a sample taken at Middle Willow Creek had a result of >=2420MPN/100 mL. 8/17/2004 - a sample taken at Middle Willow Creek had a result of 649MPN/100 mL. 8/17/2004 - a sample taken at Middle Willow Creek had a result of 816MPN/100 mL. 5/16/2005 - a sample taken at Middle Willow Creek had a result of >2420MPN/100 mL. 6/20/2005 - a sample taken at Middle Willow Creek had a result of 488MPN/100 mL. 7/18/2005 - a sample taken at Middle Willow Creek had a result of 921MPN/100 mL. 8/15/2005 - a sample taken at Middle Willow Creek had a result of 727MPN/100 mL. 1/19/2005 - a sample taken at Upper Willow Creek had a result of 613MPN/100 mL.
Data Reference: | SWAMP data entered by SWRCB into BDAT database
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. (CRWQCB, 2006)
Objective/Criterion Reference: | Central Valley Regional Water Quality Control Board. Water Quality Control Plan (Basin Plan) for the California Regional Water Quality Control Board - Central Valley Region
Evaluation Guideline: | E.Coli Bacteria levels should not exceed 235 MPN/100 mL in any single sample (USEPA E.Coli Guideline)
Guideline Reference: | Ambient Water Quality Criteria for Bacteria - 1986. EPA440/5-84-002
Spatial Representation: | Samples were collected at Lower Willow Creek. Samples were collected at Middle Willow Creek. Samples were collected at Upper Willow Creek.
Temporal Representation: | The samples were collected from May 21 2004 to Sep 19 2005
Environmental Conditions: |
QAPP Information: | Monitoring was conducted in accordance with the State Water Resources Control Board's Quality Assurance Program Plan for the State of California's Surface Water Ambient Monitoring Program.
QAPP Information Reference(s):

DECISION ID | 7151
Pollutant: | Acid Mine Drainage
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: | Resource Extraction
Expected TMDL Completion Date: | 2019
Impairment from Pollutant or Pollution: | Pollutant
Weight of Evidence: | 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.
RWQCB Board Decision / Staff Recommendation: | No new data were assessed for 2008. The Regional Board will update this decision when new data and information become available and are assessed.
SWRCB Board Decision / Staff Recommendation: | N/A
USEPA Decision: |

Lines of Evidence (LOEs) for Decision ID 7151

LOE ID: | 4581
Pollutant: | Acid Mine Drainage
LOE Subgroup: | Pollutant-Water
Matrix: | Water
Fraction: | Not Recorded
Beneficial Use: | Cold Freshwater Habitat
Number of Samples: | 0
Number of Exceedances: | 0
Data and Information Type: | Not Specified
Data Used to Asses 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)
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):

DECISION ID | 7193
Pollutant: | Copper
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: | Resource Extraction
Expected TMDL Completion Date: | 2019
Impairment from Pollutant or Pollution: | Pollutant
Weight of Evidence: | 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.
RWQCB Board Decision / Staff Recommendation: | No new data were assessed for 2008. The Regional Board will update this decision when new data and information become available and are assessed.
SWRCB Board Decision / Staff Recommendation: | N/A
USEPA Decision: |

Lines of Evidence (LOEs) for Decision ID 7193

LOE ID: | 4582
Pollutant: | Copper
LOE Subgroup: | Pollutant-Water
Matrix: | Water
Fraction: | Not Recorded
Beneficial Use: | Cold Freshwater Habitat
Number of Samples: | 0
Number of Exceedances: | 0
Data and Information Type: | Not Specified
Data Used to Asses 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)
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):

DECISION ID | 7194
Pollutant: | Zinc
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: | Resource Extraction
Expected TMDL Completion Date: | 2019
Impairment from Pollutant or Pollution: | Pollutant
Weight of Evidence: | 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.
RWQCB Board Decision / Staff Recommendation: | No new data were assessed for 2008. The Regional Board will update this decision when new data and information become available and are assessed.
SWRCB Board Decision / Staff Recommendation: | N/A
USEPA Decision: |

Lines of Evidence (LOEs) for Decision ID 7194

LOE ID: | 4583
Pollutant: | Zinc
LOE Subgroup: | Pollutant-Water
Matrix: | Water
Fraction: | Not Recorded
Beneficial Use: | Cold Freshwater Habitat
Number of Samples: | 0
Number of Exceedances: | 0
Data and Information Type: | Not Specified
Data Used to Asses 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)
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):