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

# Supporting Information

## Regional Board 5 - Central Valley Region

Water Body Name: | Sacramento River ( Cottonwood Creek to Red Bluff)
Water Body ID: | CAR5042007020021209153351
Water Body Type: | River & Stream

DECISION ID | 7156
Pollutant: | Unknown Toxicity
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)(2006)
Revision Status | Revised
Sources: | Source Unknown
Expected TMDL Completion Date: | 2019
Impairment from Pollutant or Pollution: | Pollutant
Weight of Evidence: | This pollutant is being considered for removal from the 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. Six lines of evidence are available in the administrative record to assess 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 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. Nineteen of 65 samples tested with Ceriodaphnia (survival or reproductive toxicity) exceeded the narrative toxicity objective and this exceeds the allowable frequency listed in Table 4.1 of the Listing Policy. 4. Fourteen of 33 samples tested with Pimephales (survival or growth toxicity) exceeded the narrative toxicity objective and this exceeds the allowable frequency listed in Table 4.1 of the Listing Policy. 5. In addition, 1 of 23 samples tested with Selenastrum exceeded the water quality objective and this does not exceed the allowable frequency using Table 3.1 of the Listing Policy. 6. Pursuant to section 4.11 of the Listing Policy, no additional data and information are available indicating that standards are met.
RWQCB Board Decision / Staff 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.
SWRCB Board Decision / Staff Recommendation: |
USEPA Decision: |

Lines of Evidence (LOEs) for Decision ID 7156

LOE ID: | 4514
Pollutant: | Unknown Toxicity
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 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)
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):
LOE ID: | 26218
Pollutant: | Toxicity
LOE Subgroup: | Toxicity
Matrix: | Water
Fraction: | Total
Beneficial Use: | Warm Freshwater Habitat
Number of Samples: | 33
Number of Exceedances: | 6
Data and Information Type: | TOXICITY TESTING
Data Used to Assess Water Quality: | Seven-day growth toxicity tests were conducted with Pimephales promelas. Six of the 33 samples exhibited significant reduction in growth compared to the laboratory control and violated the narrative toxicity objective. Growth endpoints for P. promelas were not statistically compared to control results if survival endpoints were significantly less than the controls. The following is a summary of the test results by year. Growth Endpoint 1998-1999 Two of the 12 samples exhibited significant reduction in growth compared to the laboratory control. Toxic samples were collected on the following dates (percent of control in parentheses): 19 August 1998 (71), and 19 May 1999 (76). 2003-2004 None of the 4 samples were reported to have exhibited significant reduction in growth compared to the laboratory control. However, growth endpoints for P. promelas were not statistically compared to control results if survival endpoints were significantly less than the controls, as was the case with samples collected on 9 June 2004 and 27 July 2004. The results reported for the 20 January 2004 and 3 February 2004 are those from tests modified to control pathogen-related mortality. 2006-2007 Four of the 17 samples exhibited significant reduction in growth compared to the laboratory control. Toxic samples were collected on the following dates (percent of control in parentheses): 20 April 2006 (79), 28 March 2007 (76), 16 May 2007 (74), and 27 June 2007 (72). The test results reported for 20 September 2006 were those of a re-test (SRWP 2008). The test organisms in the site water collected on 25 April 2007 exhibited pathogen-related mortalities and were excluded from evaluation of ambient toxicity (SRWP 2008). The 25 April 2007 sampling event was not included in this assessment.
Data Reference: | Sacramento River watershed program (SRWP) water quality database. Davis, CA
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: | 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: | Statistically significant difference from control with 7-day growth toxicity tests. Significant toxicity is defined as a statistically significant (p<0.5) reduction in growth compared to the laboratory control.
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: | All samples were collected from the Sacramento River above Bend Bridge.
Temporal Representation: | 1998 -1999: Samples were collected monthly from June 1998 through May 1999. 2003 - 2004: Sampling was scheduled to correspond to the following events/dates: mid-wet season (20 January 2004); post-organophosphate pesticide dormant spray application (3 February 2004); rice field discharge season, dry weather event (9 June 2004); and dry season, low flows (27 July 2004). 2006-2007: Sampling was generally conducted on a monthly basis from April 2006 through August 2007.
Environmental Conditions: |
QAPP Information: | Data quality: Good. Monitoring was conducted in accordance with the Quality Assurance Project Plan for Monitoring prepared for the Sacramento River Watershed Program (SRWP 1999a, 1999b, 2003, 2006). The test results reported for 20 September 2006 were those of a re-test (SRWP 2008). The test organisms in the site water collected on 25 April 2007 exhibited pathogen-related mortalities and were excluded from evaluation of ambient toxicity (SRWP 2008). The 25 April 2007 sampling event was not included in this assessment.
QAPP Information Reference(s):
LOE ID: | 26217
Pollutant: | Toxicity
LOE Subgroup: | Toxicity
Matrix: | Water
Fraction: | Total
Beneficial Use: | Warm Freshwater Habitat
Number of Samples: | 33
Number of Exceedances: | 8
Data and Information Type: | TOXICITY TESTING
Data Used to Assess Water Quality: | Seven-day survival toxicity tests were conducted with Pimephales promelas. Eight of the 33 samples exhibited a significant increase in mortality compared to the laboratory control and violated the narrative toxicity objective. The following is a summary of the test results by year. Survival Endpoint 1998-1999 Two of the 12 samples exhibited a significant increase in mortality compared to the laboratory control. The toxic samples were collected on the following dates (percent survival in parentheses): 22 July 1998 (70), 72% of control; and 17 November 1998 (72.5), 72.5% of the control. 2003-2004 Two of the 4 samples exhibited a significant increase in mortality compared to the laboratory control. The toxic samples were collected on the following dates (percent survival in parentheses): 9 June 2004 (35) and 27 July 2004 (25). The results reported for the 20 January 2004 and 3 February 2004 are those from tests modified to control pathogen-related mortality. 2006-2007 Four of the 17 samples exhibited a significant increase in mortality compared to the laboratory control. The toxic samples were collected on the following dates (survival reported as a percentage of control response is provided in the parentheses): 25 July 2006 (55), 9 November 2006 (35), 12 December 2006 (0), and 14 March 2007 (53). The test results reported for 20 September 2006 were those of a re-test (SRWP 2008). The test organisms in the site water collected on 25 April 2007 exhibited pathogen-related mortalities and were excluded from evaluation of ambient toxicity (SRWP 2008). The 25 April 2007 sampling event was not included in this assessment. Phase I Toxicity Identification Evaluations (TIEs) were conducted using the 9 November 2006 sample. However, pathogen-related mortality occurred in the TIE ambient water treatments, which interfered with the interpretation of the TIE (SRWP 2008). Phase I TIEs were also conducted using the 12 December 2006 sample. Although persistent during the TIEs, the toxicity was delayed and its magnitude was decreased. Toxicity was removed by the following TIE treatments: C-8 Solid Phase Extraction, Chelex column extraction, and piperonyl butoxide (PBO). This suggests that dissolved non-polar organic contaminants, divalent cations, and metabolically-activated substances, or a substance with all of these properties, caused the toxicity (SRWP 2008).
Data Reference: | Sacramento River watershed program (SRWP) water quality database. Davis, CA
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: | 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: | Statistically significant difference from control with 7-day survival toxicity tests. Significant toxicity is defined as a statistically significant (p<0.5) increase in mortality (≥20%) compared to the laboratory control.
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: | All samples were collected from the Sacramento River above Bend Bridge.
Temporal Representation: | 1998 -1999: Samples were collected monthly from June 1998 through May 1999. 2003 - 2004: Sampling was scheduled to correspond to the following events/dates: mid-wet season (20 January 2004); post-organophosphate pesticide dormant spray application (3 February 2004); rice field discharge season, dry weather event (9 June 2004); and dry season, low flows (27 July 2004). 2006-2007: Sampling was generally conducted on a monthly basis from April 2006 through August 2007.
Environmental Conditions: |
QAPP Information: | Data quality: Good. Monitoring was conducted in accordance with the Quality Assurance Project Plan for Monitoring prepared for the Sacramento River Watershed Program (SRWP 1999a, 1999b, 2003, 2006). The test results reported for 20 September 2006 were those of a re-test (SRWP 2008). The test organisms in the site water collected on 25 April 2007 exhibited pathogen-related mortalities and were excluded from evaluation of ambient toxicity (SRWP 2008). The 25 April 2007 sampling event was not included in this assessment.
QAPP Information Reference(s):
LOE ID: | 22766
Pollutant: | Toxicity
LOE Subgroup: | Toxicity
Matrix: | Water
Fraction: | Total
Beneficial Use: | Warm Freshwater Habitat
Number of Samples: | 65
Number of Exceedances: | 13
Data and Information Type: | TOXICITY TESTING
Data Used to Assess Water Quality: | Seven-day reproduction toxicity tests were conducted with Ceriodaphnia dubia in association with Sacramento River Watershed Program annual monitoring activities. Thirteen of the 65 samples exhibited significant reduction in reproduction compared to the laboratory control and violated the narrative toxicity objective. The following is a summary of toxicity test results by year.Reproduction Endpoint1998-1999Three of the 12 samples exhibited significant reduction in reproduction compared to the laboratory control. Toxic samples were collected on the following dates (percent of control in parentheses): 22 July 1998 (79), 19 August 1998 (58), and 16 September 1998 (56).1999-2000Two of the 12 samples exhibited significant reduction in reproduction compared to the laboratory control. Toxic samples were collected on the following dates (percent of control in parentheses): 16 November 1999 (68) and 16 February 2000 (75). 2000-2001Three of the 9 samples exhibited significant reduction in reproduction compared to the laboratory control. Toxic samples were collected on the following dates: 30 October 2000, 26 January 2001, and 7 February 2001. The data summary does not provide the corresponding data for the control associated with each test, but rather provides the range of data for separate controls associated multiple tests. Therefore, percent of control was not calculated.2001-2002One of the 4 samples exhibited significant reduction in reproduction compared to the laboratory control. The toxic sample was collected on 19 February 2002. Percent of control not included for same reason as 2000-2001 monitoring summary. 2002-2003None of the 6 samples exhibited significant reduction in reproduction compared to the laboratory control. 2003-2004One of the 4 samples exhibited significant reduction in reproduction compared to the laboratory control. The toxic sample was collected on 27 July 2004. Percent of control not included for same reason as 2000-2001 monitoring summary.2006-2007Three of the 18 samples exhibited significant reduction in reproduction compared to the laboratory control. The toxic samples were collected on the following dates (percentage of control response provided in parentheses): 25 October 2006 (77), 14 March 2007 (86), and 25 April 2007 (60).
Data Reference: | Sacramento River watershed program (SRWP) water quality database. Davis, CA
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: | 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: | Statistically significant difference from control with 7-day reproduction toxicity tests. Significant toxicity is defined as decreased reproduction that is statistically different from controls at the 95% confidence level.
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: | All samples were collected from the Sacramento River above Bend Bridge.
Temporal Representation: | 1998 - 1999: Samples were collected monthly from June 1998 through May 1999. 1999 - 2000: Samples were collected monthly from June 1999 through May 2000. 2000 - 2001: Samples were collected on 19 July 2000, 19 September 2000, 17 October 2000, 30 October 2000, 26 January 2001, 7 February 2001, 8 April 2001, 29 May 2001, and 21 June 2001. 2001 - 2002: Sampling was scheduled to correspond to the following events/dates: late dry season, low flows (24 September 2001); seasonal first-flush storm (2 November 2001); significant rainfall of >0.5 inches, organophosphate pesticide application period (19 February 2002); and rice field discharge period, late wet season (14 May 2002). 2002 - 2003: Sampling was scheduled to correspond to the following events/dates: late dry season, low flows (1 October 2002); first significant storm event of season (9 November 2002); significant rain event (15 February 2003), late wet season, rain events (14 March 2003 and 4 April 2003); and rice field discharge season, dry weather event (9 June 2003). 2003 - 2004: Sampling was scheduled to correspond to the following events/dates: mid-wet season (20 January 2004); post-organophosphate pesticide dormant spray application (3 February 2004); rice field discharge season, dry weather event (9 June 2004); and dry season, low flows (27 July 2004). 2006 - 2007: Sampling was generally conducted on a monthly basis from April 2006 through August 2007.
Environmental Conditions: |
QAPP Information: | Data quality: Good. Monitoring was conducted in accordance with the Quality Assurance Project Plan for Monitoring prepared for the Sacramento River Watershed Program (SRWP 1999a, 1999b, 2000b, 2001b, 2002b, 2003b, 2006).
QAPP Information Reference(s):
LOE ID: | 22632
Pollutant: | Toxicity
LOE Subgroup: | Toxicity
Matrix: | Water
Fraction: | Total
Beneficial Use: | Warm Freshwater Habitat
Aquatic Life Use: | Warm Freshwater Habitat
Number of Samples: | 65
Number of Exceedances: | 6
Data and Information Type: | TOXICITY TESTING
Data Used to Assess Water Quality: | Seven-day survival toxicity tests were conducted with Ceriodaphnia dubia in association with Sacramento River Watershed Program annual monitoring activities. Six of the 65 samples exhibited a significant increase in mortality compared to the laboratory control and violated the narrative toxicity objective. The following is a summary of toxicity test results by year.Survival Endpoint1998-1999None of the 12 samples exhibited a significant increase in mortality compared to the laboratory control.1999-2000None of the 12 samples exhibited a significant increase in mortality compared to the laboratory control. 2000-2001One of the 9 samples exhibited a significant increase in mortality compared to the laboratory control. The toxic sample was collected on 19 September 2000 (100% mortality). 2001-2002Two of the 4 samples exhibited a significant increase in mortality compared to the laboratory control. Toxic samples were collected on 24 September 2001 (100% mortality) and 14 May 2002 (40% mortality).2002-2003One of the 6 samples exhibited a significant increase in mortality compared to the laboratory control. The toxic sample was collected on 14 March 2003 (100% mortality). 2003-2004One of the 4 samples exhibited a significant increase in mortality compared to the laboratory control. The toxic sample was collected on 9 June 2004 (100% mortality).Targeted Toxicity Identification Evaluations (TIEs) were initiated using Ceriodaphnia with the toxic sample from the Sacramento River at Bend, but toxicity was not persistent in the original sample at the time of re-testing. No further evaluations were conducted with this sample. 2006-2007One of the 18 samples exhibited a significant increase in mortality compared to the laboratory control. The toxic sample was collected on 12 December 2006 (initial test: 0% of control, immediate re-test: 50% of control). It should be noted that of the 12 water samples collected from across the watershed during this sampling event (December 2006), 11 caused complete mortality of the test organisms in the initial test.Phase I Toxicity Identification Evaluations (TIEs) were conducted using the 12 December 2006 sample. Although persistent during the TIEs, the toxicity was delayed and its magnitude was decreased. Toxicity was removed by the following TIE treatments: C-8 Solid Phase Extraction and piperonyl butoxide (PBO). This suggests that dissolved non-polar organic contaminants and metabolically-activated substances, or a substance with both properties, caused the toxicity (SRWP 2008).
Data Reference: | Sacramento River watershed program (SRWP) water quality database. Davis, CA
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: | 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: | Statistically significant difference from control with 7-day survival toxicity tests. Significant toxicity is defined as mortality (=20%) that is statistically different from controls at the 95% confidence level.
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: | All samples were collected from the Sacramento River above Bend Bridge.
Temporal Representation: | 1998 -1999: Samples were collected monthly from June 1998 through May 1999. 1999 - 2000: Samples were collected monthly from June 1999 through May 2000. 2000 - 2001: Samples were collected on 19 July 2000, 19 September 2000, 17 October 2000, 30 October 2000, 26 January 2001, 7 February 2001, 8 April 2001, 29 May 2001, and 21 June 2001. 2001 - 2002: Sampling was scheduled to correspond to the following events/dates: late dry season, low flows (24 September 2001); seasonal first-flush storm (2 November 2001); significant rainfall of >0.5 inches, organophosphate pesticide application period (19 February 2002); and rice field discharge period, late wet season (14 May 2002). 2002 - 2003: Sampling was scheduled to correspond to the following events/dates: late dry season, low flows (1 October 2002); first significant storm event of season (9 November 2002); significant rain event (15 February 2003), late wet season, rain events (14 March 2003 and 4 April 2003); and rice field discharge season, dry weather event (9 June 2003). 2003 - 2004: Sampling was scheduled to correspond to the following events/dates: mid-wet season (20 January 2004); post-organophosphate pesticide dormant spray application (3 February 2004); rice field discharge season, dry weather event (9 June 2004); and dry season, low flows (27 July 2004). 2006 - 2007: Sampling was generally conducted on a monthly basis from April 2006 through August 2007.
Environmental Conditions: |
QAPP Information: | Data quality: Good. Monitoring was conducted in accordance with the Quality Assurance Project Plan for Monitoring prepared for the Sacramento River Watershed Program (SRWP 1999a, 1999b, 2000b, 2001b, 2002b, 2003b, 2006).
QAPP Information Reference(s):
LOE ID: | 22781
Pollutant: | Toxicity
LOE Subgroup: | Toxicity
Matrix: | Water
Fraction: | Total
Beneficial Use: | Warm Freshwater Habitat
Aquatic Life Use: | Warm Freshwater Habitat
Number of Samples: | 23
Number of Exceedances: | 1
Data and Information Type: | TOXICITY TESTING
Data Used to Assess Water Quality: | Four-day growth tests were conducted with Selenastrum capricornutum in association with Sacramento River Watershed Program annual monitoring activities. One of the 23 samples exhibited a significant decrease in growth as compared to the laboratory control and violated the narrative toxicity objective.The following is a summary of monitoring results by year.1999-2000A single sample was collected on 19 January 2000. The sample did not exhibit a significant decrease in growth (cell numbers) as compared to the laboratory control. 2003-2004None of the 4 samples exhibited a significant decrease in growth (cell numbers) as compared to the laboratory control. 2006-2007One of the 18 samples exhibited a significant decrease in growth as compared to the laboratory control. The toxic sample (growth response reported as a percentage of control response is provided in parentheses) was collected on 23 August 2006 (76). The results reported for the sample collected on 6 July 2006 were those of a re-test (SRWP 2008).
Data Reference: | Sacramento River watershed program (SRWP) water quality database. Davis, CA
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: | 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: | Statistically significant difference from control with a short-term chronic (4-day) growth test.
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: | All samples were collected from the Sacramento River above Bend Bridge.
Temporal Representation: | 1999-2000: A single sample was collected on 19 January 2000. 2003-2004: Sampling was scheduled to correspond to the following events/dates: mid-wet season (20 January 2004); post-organophosphate pesticide dormant spray application (3 February 2004); rice field discharge season, dry weather event (9 June 2004); and dry season, low flows (27 July 2004). 2006-2007: Sampling was generally conducted on a monthly basis from April 2006 through August 2007.
Environmental Conditions: |
QAPP Information: | Data quality: Good. Monitoring was conducted in accordance with the Quality Assurance Project Plan for Monitoring prepared for the Sacramento River Watershed Program (SRWP 1999a, 1999b, 2000b, 2001b, 2002b, 2003b, 2006).
QAPP Information Reference(s):

DECISION ID | 15763
Pollutant: | Mercury
Final Listing Decision: | List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: | New Decision
Revision Status | Revised
Sources: | Resource Extraction
Expected TMDL Completion Date: | 2021
Impairment from Pollutant or Pollution: | Pollutant
Weight of Evidence: | 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. Four lines of evidence are available in the administrative record to assess this pollutant. Ten of the samples exceed the water quality objective. 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 86 samples exceed the USEPA fish tissue criterion for human health 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.
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 15763

LOE ID: | 26363
Pollutant: | Mercury
LOE Subgroup: | Pollutant-Tissue
Matrix: | Tissue
Fraction: | Total
Beneficial Use: | Commercial or recreational collection of fish, shellfish, or organisms
Number of Samples: | 37
Number of Exceedances: | 6
Data and Information Type: | PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: | Fish were sampled for tissue analysis at one location from this reach. A total of 6 out of 37 samples exceeded the USEPA fish tissue criterion for human health. The average wet weight mercury concentration in fish tissue was 0.15 ppm for the 37 samples collected. The number of fish collected per sample, the measured mercury concentrations in fish tissue, and the number of exceedences are, by species: Hardhead- 5 samples, 0.13-0.55 ppm (average 0.32 ppm), 3 exceedences; Rainbow Trout- 12 samples, 0.01-0.07 ppm (average 0.03 ppm), no exceedences; Sacramento Pikeminnow- 10 samples, 0.14-0.91 ppm (average 0.31 ppm), 3 exceedences; Sacramento Sucker- 10 samples, 0.03-0.10 ppm (average 0.05 ppm), no exceedences. All 37 samples were collected from fish with total lengths greater than 150 mm, which represent fish most commonly caught and consumed by sport fishers and their families.
Data Reference: | Fish Mercury Project, Year 1 Annual Report, Sport Fish Sampling and Analysis. Collaborating parties: San Francisco Estuary Institute, California Department of Fish and Game, Moss Landing Marine Laboratories, California Office of Environmental Health Hazard Assessment. Final Technical Report. CBDA Project # ERP 02D-P6729. May 2007
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: | 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: | The USEPA Fish Tissue Residue Criterion for methylmercury in fish is 0.3 mg/kg (0.3 ppm) for the protection of human health. This is the concentration in fish tissue that should not be exceeded based on a total fish and shellfish consumption-weighted rate of 0.0175 kg fish/day. (USEPA, 2001)
Guideline Reference: | Water Quality Criterion for the Protection of Human Health: Methylmercury. Final. United States Environmental Protection Agency Office of Science and Technology Office of Water. EPA-823-R-01-001. January 2001
Spatial Representation: | Samples were collected at one location from this reach of the Sacramento River approximately 0.5 miles downstream from the Bend Bridge crossing.
Temporal Representation: | Fish samples were collected during one sampling event on 8/16/2005.
Environmental Conditions: | Significant gold mining activity occurred during the Gold Rush era within the Sacramento River watershed (USGS, 2005).
QAPP Information: | Data quality: Excellent.. Puckett, H.M. and B.H. van Buuren. 2000. Quality Assurance Project Plan for the CALFED Mercury Project. California Department of Fish and Game, Granite Canyon Marine Pollution Studies Laboratories, Monterey, CA; and Frontier Geosciences, Inc., Seattle, WA. March 2000.
QAPP Information Reference(s):
LOE ID: | 26353
Pollutant: | Mercury
LOE Subgroup: | Pollutant-Tissue
Matrix: | Tissue
Fraction: | Total
Beneficial Use: | Commercial or recreational collection of fish, shellfish, or organisms
Number of Samples: | 26
Number of Exceedances: | 2
Data and Information Type: | PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: | Fish were sampled for tissue analysis at one location from this reach. A total of 2 out of 26 samples exceeded the USEPA fish tissue criterion for human health. The average wet weight mercury concentration in fish tissue was 0.13 ppm for all 26 samples collected. The number of fish collected per sample, the measured mercury concentrations in fish tissue, and the number of exceedences are, by species: Rainbow Trout- 10 samples, 0.01-0.12 ppm (average 0.03 ppm), no exceedences; Sacramento Pikeminnow- 6 samples, 0.13-1.24 ppm (average 0.42 ppm), 2 exceedences; Sacramento Sucker- 10 samples, 0.01-0.10 ppm (average 0.06 ppm), no exceedences. All 26 samples were collected from fish with total lengths greater than 150 mm, which represent fish most commonly caught and consumed by sport fishers and their families.
Data Reference: | CVRWQCB. 2004. TMDL Fish Tissue Sampling- Cache Creek and Sacramento River Watersheds. Central Valley Regional Water Quality Control Board; and California Department of Fish and Game. Unpublished Data. August 2004.
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: | 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: | The USEPA Fish Tissue Residue Criterion for methylmercury in fish is 0.3 mg/kg (0.3 ppm) for the protection of human health. This is the concentration in fish tissue that should not be exceeded based on a total fish and shellfish consumption-weighted rate of 0.0175 kg fish/day. (USEPA, 2001)
Guideline Reference: | Water Quality Criterion for the Protection of Human Health: Methylmercury. Final. United States Environmental Protection Agency Office of Science and Technology Office of Water. EPA-823-R-01-001. January 2001
Spatial Representation: | Samples were collected at one location from this reach of the Sacramento River at the Bend Bridge crossing.
Temporal Representation: | Fish samples were collected during one sampling event on 11/5/2003.
Environmental Conditions: | Significant gold mining activity occurred during the Gold Rush era within the Sacramento River watershed (USGS, 2005).
QAPP Information: | Data quality: Excellent. Quality Control for all of the elements described in section 6.1.4 of the Policy was conducted in accordance with the CALFED Mercury Project QAPP (Puckett and van Buuren, 2000).
QAPP Information Reference(s):
LOE ID: | 26355
Pollutant: | Mercury
LOE Subgroup: | Pollutant-Tissue
Matrix: | Tissue
Fraction: | Total
Beneficial Use: | Commercial or recreational collection of fish, shellfish, or organisms
Number of Samples: | 19
Number of Exceedances: | 2
Data and Information Type: | PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: | Fish were sampled for tissue analysis at one location from this reach. A total of 2 out of 19 samples exceeded the USEPA fish tissue criterion for human health. The average wet weight mercury concentration in fish tissue was 0.09 ppm for the 19 samples collected. The number of fish collected per sample, the measured mercury concentrations in fish tissue, and the number of exceedences are, by species: Rainbow Trout- 12 samples, 0.02-0.06 ppm (average 0.04 ppm), no exceedences; Sacramento Pikeminnow- 2 samples, 0.38 and 0.52 ppm, 2 exceedences; Sacramento Sucker- 5 samples, 0.03-0.12 ppm (average 0.08 ppm), no exceedences. All 19 samples were collected from fish with total lengths greater than 150 mm, which represent fish most commonly caught and consumed by sport fishers and their families.
Data Reference: | Fish Mercury Project, Year 2 Annual Report, Sport Fish Sampling and Analysis. Final Report. October 2007
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: | 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: | The USEPA Fish Tissue Residue Criterion for methylmercury in fish is 0.3 mg/kg (0.3 ppm) for the protection of human health. This is the concentration in fish tissue that should not be exceeded based on a total fish and shellfish consumption-weighted rate of 0.0175 kg fish/day. (USEPA, 2001)
Guideline Reference: | Water Quality Criterion for the Protection of Human Health: Methylmercury. Final. United States Environmental Protection Agency Office of Science and Technology Office of Water. EPA-823-R-01-001. January 2001
Spatial Representation: | Samples were collected at one location from this reach of the Sacramento River approximately 0.5 miles downstream from the Bend Bridge crossing.
Temporal Representation: | Fish samples were collected during one sampling event on 7/19/2006.
Environmental Conditions: | Significant gold mining activity occurred during the Gold Rush era within the Sacramento River watershed (USGS, 2005).
QAPP Information: | Data quality: Excellent.. Puckett, H.M. and B.H. van Buuren. 2000. Quality Assurance Project Plan for the CALFED Mercury Project. California Department of Fish and Game, Granite Canyon Marine Pollution Studies Laboratories, Monterey, CA; and Frontier Geosciences, Inc., Seattle, WA. March 2000.
QAPP Information Reference(s):
LOE ID: | 26354
Pollutant: | Mercury
LOE Subgroup: | Pollutant-Tissue
Matrix: | Tissue
Fraction: | Total
Beneficial Use: | Commercial or recreational collection of fish, shellfish, or organisms
Number of Samples: | 4
Number of Exceedances: | 0
Data and Information Type: | PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: | Fish were sampled for tissue analysis at two locations near the Bend Bridge crossing. A total of 0 out of 4 samples exceeded the USEPA fish tissue criterion for human health. The average wet weight mercury concentration in fish tissue was 0.07 ppm for all 4 samples collected. The number of fish collected per sample, the measured mercury concentrations in fish tissue, and the number of exceedences are, by species: Rainbow Trout- 2 composite samples, 0.03 and 0.04 ppm, no exceedences; Sacramento Pikeminnow- one 5-fish composite sample, 0.12 ppm, no exceedences; Sacramento Sucker- one 5-fish composite sample, 0.10 ppm, no exceedences. All 4 composite samples were collected from fish with average total lengths greater than 150 mm, which represent fish most commonly caught and consumed by sport fishers and their families.
Data Reference: | Sacramento River Watershed Program Annual Reports for 1999-2000, 2000-2001, 2001-2002, 2002-2003, and 2003-2004; and BDAT data 1998-2003
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: | 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: | The USEPA Fish Tissue Residue Criterion for methylmercury in fish is 0.3 mg/kg (0.3 ppm) for the protection of human health. This is the concentration in fish tissue that should not be exceeded based on a total fish and shellfish consumption-weighted rate of 0.0175 kg fish/day. (USEPA, 2001)
Guideline Reference: | Water Quality Criterion for the Protection of Human Health: Methylmercury. Final. United States Environmental Protection Agency Office of Science and Technology Office of Water. EPA-823-R-01-001. January 2001
Spatial Representation: | Samples were collected at two locations from this reach of the Sacramento River: at the Bend Bridge crossing; and approximately 2.6 miles upstream of the Bend Bridge crossing.
Temporal Representation: | Fish samples were collected during three sampling events conducted during 1997, 1998 and 2000.
Environmental Conditions: | Significant gold mining activity occurred during the Gold Rush era within the Sacramento River watershed (USGS, 2005).
QAPP Information: | Data quality: Excellent.. Monitoring was conducted in accordance with the Quality Assurance Project Plan for Monitoring prepared for the Sacramento River Watershed Program (SRWP 1998, 2000b)
QAPP Information Reference(s): | Quality Assurance Project Plans prepared for Sacramento River Watershed Program