Draft California 2018 Integrated Report (303(d) List/305(b) Report)

Supporting Information

Regional Board 6 - Lahontan Region

Water Body Name:	Amargosa River (Tecopa to Upper Canyon)
Water Body ID:	CAR6094200020080816182154
Water Body Type:	River & Stream


DECISION ID	76462	Region 6
Amargosa River (Tecopa to Upper Canyon)

Pollutant:	Arsenic
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)(2016)
Revision Status	Revised
Sources:	Source Unknown
Expected TMDL Completion Date:	2031
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Staff Conclusion:	This pollutant is being considered for removal from the CWA section 303(d) List under section 4.1 of the Listing Policy. Under this section a single line of evidence is necessary to assess listing status. Four lines of evidence are available in the administrative record to assess pollutant, three from a past cycle that assess for inland saline habitat and one that assesses for WARM. Two of four samples exceed the guideline for inland surface water, zero of one samples exceeds the sediment guideline and one of one samples exceeds the WARM criteria for arsenic. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against removing this water segment-pollutant combination from the CWA section 303(d) List. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. Two of four samples exceed the guideline for inland surface water, zero of one samples exceeds the sediment guideline and one of one samples exceeds the WARM criteria for arsenic and this exceeds the allowable frequency listed in Table 4.1 of the Listing Policy. 4. Pursuant to section 4.11 of the Listing Policy, no additional data and information are available indicating that standards are met.

Regional Board Staff Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be removed from the section 303(d) list because applicable water quality standards for the pollutant are being exceeded.

Line of Evidence (LOE) for Decision ID 76462, Arsenic	Region 6
Amargosa River (Tecopa to Upper Canyon)

LOE ID:

25007

Pollutant:

Arsenic

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Inland Saline Water Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

The U.S. Geological Survey sampled this station on March 17, 2004 and March 15, 2005 under the Region 6 SWAMP program. Two samples had dissolved arsenic concentations of 226 and 166 ug/L.

Data Reference:

2007. SWAMP Data for the Amargosa Hydrologic Unit

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The California Toxics Rule's saltwater aquatic life standards for arsenic are an acute toxicity limit of 69 ug/L and a chronic toxicity limit of 36 ug/L.

Objective/Criterion Reference:

Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

One station, Amargosa River at Upper Canyon, was sampled.

Temporal Representation:

Two samples were collected on March 17, 2004 and March 15, 2005.

Environmental Conditions:

The Amargosa River flows into California from Nevada and terminates in Death Valley. It is mostly ephemeral but there are perennial reaches. There is great seasonal and annual variability in flows. Most of the watershed is U.S. Bureau of Land Management or National Park land.

The Amargosa River is not designated for the Municipal and Domestic Supply (MUN) beneficial use. The MUN use designation was removed in Basin Plan amendments that took effect in 2002. The rationale for removing the use included naturally high salinity and levels of toxic substances such as arsenic, and fluctuating water quantity that would make the river an unreliable supply if treatment were feasible.

The perennial reaches of the Amargosa River and the associated riparian areas support a complex of rare, threatened or endangered fish and wildlife species. To Lahontan Water Board staff¿s knowledge, there are no salmonids in the river and there is no warm water fishery for human consumption.

QAPP Information:

The data meet the quality assurance requirements of the SWAMP QAPP.

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 76462, Arsenic	Region 6
Amargosa River (Tecopa to Upper Canyon)

LOE ID:

25005

Pollutant:

Arsenic

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Inland Saline Water Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

The U.S. Geological Survey sampled this station on March 17, 2004 and March 15, 2005 under the Region 6 SWAMP program. Two samples had total arsenic concentrations of 231 and 173 ug/L.

Data Reference:

2007. SWAMP Data for the Amargosa Hydrologic Unit

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

There are no applicable state or federal saltwater aquatic life standards or criteria for total arsenic in inland saline waters.

Objective/Criterion Reference:

Water Quality Control Plan for the Lahontan Region (as amended)

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

One station, Amargosa River at Upper Canyon, was sampled.

Temporal Representation:

Two samples were collected on March 17, 2004 and March 15, 2005.

Environmental Conditions:

QAPP Information:

The data meet the quality assurance requirements of the SWAMP QAPP.

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 76462, Arsenic	Region 6
Amargosa River (Tecopa to Upper Canyon)

LOE ID:

98846

Pollutant:

Arsenic

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed NWIS data for Amargosa River (Tecopa to Upper Canyon) to determine beneficial use support and results are as follows: 1 of 1 samples exceeded the water quality standard for Arsenic.

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for the USGS National Water Information System.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The dissolved arsenic criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in freshwater for dissolved arsenic is 0.150 mg/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site(s) (USGS-10251300)

Temporal Representation:

The samples were collected between the dates of 2014-03-27 and 2014-03-27

Environmental Conditions:

QAPP Information:

QAPP not required for federal data

QAPP Information Reference(s):

This is a placeholder reference for data which does not require a QAPP.

Line of Evidence (LOE) for Decision ID 76462, Arsenic	Region 6
Amargosa River (Tecopa to Upper Canyon)

LOE ID:

24855

Pollutant:

Arsenic

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

None

Beneficial Use:

Inland Saline Water Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Chemical monitoring of sediments

Data Used to Assess Water Quality:

The U.S. Geological Survey sampled sediment at this station on March 15, 2005 under the Region 6 SWAMP program. Results were reported as "bed sediment, smaller than 62.5 um, wet sieved, total digestion." The concentration of arsenic was 7.2 ug/g dry weight.

Data Reference:

2007. SWAMP Data for the Amargosa Hydrologic Unit

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

There are no state or federal standards or criteria for arsenic in sediment in inland saline waters. The Effects Range-Median for arsenic in marine and estuarine sediments is 70 ug/g dry weight; see Long et al. (1995).

Objective/Criterion Reference:

Incidence of adverse biological effects within ranges of chemical concentrations in marine and estuary sediments. Environmental Management. 19, (1): 81-97

Water Quality Control Plan for the Lahontan Region (as amended)

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

One station, Amargosa River at Upper Canyon, was sampled.

Temporal Representation:

One sediment sample was collected on March 15, 2005.

Environmental Conditions:

QAPP Information:

The data meet the quality assurance requirements of the SWAMP QAPP.

QAPP Information Reference(s):


DECISION ID	72585	Region 6
Amargosa River (Tecopa to Upper Canyon)

Pollutant:	Antimony
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2016)
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Staff Conclusion:	This pollutant is being considered for placement on the CWA section 303(d) List under section 3.1 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status. Four lines of evidence are available in the administrative record to assess this pollutant, three that assess for inland saline habitat and one that assesses for WARM. The lines of evidence from 2010 do not include an objective or criteria for antimony so the decision exceedance count is based on the 2018 line of evidence for WARM. Zero of one samples exceed the guideline for antimony. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the CWA section 303(d) List in the Water Quality Limited Segments category. This conclusion is based on the staff findings that: 1. The data used 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 one samples exceeded the guideline 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 Staff Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.

Line of Evidence (LOE) for Decision ID 72585, Antimony	Region 6
Amargosa River (Tecopa to Upper Canyon)

LOE ID:

98933

Pollutant:

Antimony

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed NWIS data for Amargosa River (Tecopa to Upper Canyon) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality standard for Antimony.

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for the USGS National Water Information System.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life (Water Quality Control Plan, Lahontan Region). The USEPA Lowest Observed Effect Levels (LOEL) criteria for protection of aquatic life include an acute antimony value of 9000 ug/L, a chronic value of 1600 ug/L and a limit for toxicity to algae of 610 ug/L. This data were compared to the most protective limit of 610 ug/L.

Objective/Criterion Reference:

Water Quality Control Plan for the Lahontan Region (as amended)

Evaluation Guideline:

The Gold Book states that toxicity to algae occurs at antimony concentrations as low as 610 ug/L.

Guideline Reference:

Quality Criteria for Water 1986. United States Environmental Protection Agency. Office of Water. Regulations and Standards. Washington D.C. EPA 440/5-86-001.

Spatial Representation:

The samples were collected at 1 monitoring site(s) (USGS-10251300)

Temporal Representation:

The samples were collected between the dates of 2014-03-27 and 2014-03-27

Environmental Conditions:

QAPP Information:

QAPP not required for federal data

QAPP Information Reference(s):

This is a placeholder reference for data which does not require a QAPP.

Line of Evidence (LOE) for Decision ID 72585, Antimony	Region 6
Amargosa River (Tecopa to Upper Canyon)

LOE ID:

24851

Pollutant:

Antimony

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

None

Beneficial Use:

Inland Saline Water Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Chemical monitoring of sediments

Data Used to Assess Water Quality:

Data Reference:

2007. SWAMP Data for the Amargosa Hydrologic Unit

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

There are no state or federal standards or criteria for antimony in sediment in inland saline waters. The Effects Range-Median for antimony in marine and estuarine sediments is 25 ug/g dry weight; see Long et al. (1995).

Objective/Criterion Reference:

Incidence of adverse biological effects within ranges of chemical concentrations in marine and estuary sediments. Environmental Management. 19, (1): 81-97

Water Quality Control Plan for the Lahontan Region (as amended)

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

One station, Amargosa River at Upper Canyon, was sampled.

Temporal Representation:

One sediment sample was collected on March 15, 2005.

Environmental Conditions:

QAPP Information:

The data meet the quality assurance requirements of the SWAMP QAPP.

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 72585, Antimony	Region 6
Amargosa River (Tecopa to Upper Canyon)

LOE ID:

24995

Pollutant:

Antimony

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Inland Saline Water Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

The U.S. Geological Survey sampled this station on March 17, 2004 and March 15, 2005 under the Region 6 SWAMP program. The concentrations of dissolved antimony in two samples were 0.6 and 0.55 ug/L.

Data Reference:

2007. SWAMP Data for the Amargosa Hydrologic Unit

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

There are no applicable state or federal saltwater aquatic life standards or criteria for dissolved antimony in inland saline waters.

Objective/Criterion Reference:

Water Quality Control Plan for the Lahontan Region (as amended)

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

One station, Amargosa River at Upper Canyon, was sampled.

Temporal Representation:

Two samples were collected on March 17, 2004 and March 15, 2005.

Environmental Conditions:

QAPP Information:

The data meet the quality assurance requirements of the SWAMP QAPP.

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 72585, Antimony	Region 6
Amargosa River (Tecopa to Upper Canyon)

LOE ID:

24994

Pollutant:

Antimony

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Inland Saline Water Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

The U.S. Geological Survey sampled this station on March 17, 2004 and March 15, 2005 under the Region 6 SWAMP program. The concentrations of total antimony in two samples were 0.5 and 0.5 ug/L.

Data Reference:

2007. SWAMP Data for the Amargosa Hydrologic Unit

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

There are no applicable state or federal saltwater aquatic life standards or criteria for total antimony in inland saline waters.

Objective/Criterion Reference:

Water Quality Control Plan for the Lahontan Region (as amended)

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

One station, Amargosa River at Upper Canyon, was sampled.

Temporal Representation:

Two samples were collected on March 17, 2004 and March 15, 2005.

Environmental Conditions:

QAPP Information:

The data meet the quality assurance requirements of the SWAMP QAPP.

QAPP Information Reference(s):


DECISION ID	72852	Region 6
Amargosa River (Tecopa to Upper Canyon)

Pollutant:	Beryllium
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2016)
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Staff Conclusion:	This pollutant is being considered for placement on the CWA section 303(d) List under section 3.1 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status. Four lines of evidence are available in the administrative record to assess this pollutant, three from a previous cycle that assess for inland saline habitat and one that assesses for WARM. The lines of evidence from 2010 do not include an assessment criteria or objective so the decision exceedance count is based on the WARM line of evidence from 2018. Zero of one samples exceed the guideline. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the CWA section 303(d) List 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. Zero of one samples exceeded the guideline 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 Staff Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.

Line of Evidence (LOE) for Decision ID 72852, Beryllium	Region 6
Amargosa River (Tecopa to Upper Canyon)

LOE ID:

98914

Pollutant:

Beryllium

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for the USGS National Water Information System.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan for the Lahontan Region (as amended)

Evaluation Guideline:

The Gold Book states that beryllium chronic toxicity to freshwater aquatic life occur at concentrations as low as 5.3 ug/L.

Guideline Reference:

Quality Criteria for Water 1986. United States Environmental Protection Agency. Office of Water. Regulations and Standards. Washington D.C. EPA 440/5-86-001.

Spatial Representation:

The samples were collected at 1 monitoring site(s) (USGS-10251300)

Temporal Representation:

The samples were collected between the dates of 2014-03-27 and 2014-03-27

Environmental Conditions:

QAPP Information:

QAPP not required for federal data

QAPP Information Reference(s):

This is a placeholder reference for data which does not require a QAPP.

Line of Evidence (LOE) for Decision ID 72852, Beryllium	Region 6
Amargosa River (Tecopa to Upper Canyon)

LOE ID:

24857

Pollutant:

Beryllium

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

None

Beneficial Use:

Inland Saline Water Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Chemical monitoring of sediments

Data Used to Assess Water Quality:

Data Reference:

2007. SWAMP Data for the Amargosa Hydrologic Unit

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

There are no state or federal standards or criteria for beryllium in sediment in inland saline waters.

Objective/Criterion Reference:

Water Quality Control Plan for the Lahontan Region (as amended)

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

One station, Amargosa River at Upper Canyon, was sampled.

Temporal Representation:

One sediment sample was collected on March 15, 2005.

Environmental Conditions:

QAPP Information:

The data meet the quality assurance requirements of the SWAMP QAPP.

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 72852, Beryllium	Region 6
Amargosa River (Tecopa to Upper Canyon)

LOE ID:

24996

Pollutant:

Beryllium

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Inland Saline Water Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

The U.S. Geological Survey sampled this station on March 17, 2004 and March 15, 2005 under the Region 6 SWAMP program. Two dissolved berylliium samples both had concentrations below the detection level.

Data Reference:

2007. SWAMP Data for the Amargosa Hydrologic Unit

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

There are no applicable state or federal saltwater aquatic life standards or criteria for dissolved beryllium in inland saline waters.

Objective/Criterion Reference:

Water Quality Control Plan for the Lahontan Region (as amended)

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

One station, Amargosa River at Upper Canyon, was sampled.

Temporal Representation:

Two samples were collected on March 17, 2004 and March 15, 2005.

Environmental Conditions:

QAPP Information:

The data meet the quality assurance requirements of the SWAMP QAPP.

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 72852, Beryllium	Region 6
Amargosa River (Tecopa to Upper Canyon)

LOE ID:

24997

Pollutant:

Beryllium

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Inland Saline Water Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

The U.S. Geological Survey sampled this station on March 17, 2004 and March 15, 2005 under the Region 6 SWAMP program. One of two samples for total beryllium was below the detection level and the other was an estimated value..

Data Reference:

2007. SWAMP Data for the Amargosa Hydrologic Unit

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

There are no applicable state or federal saltwater aquatic life standards or criteria for total beryllium in inland saline waters.

Objective/Criterion Reference:

Water Quality Control Plan for the Lahontan Region (as amended)

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

One station, Amargosa River at Upper Canyon, was sampled.

Temporal Representation:

Two samples were collected on March 17, 2004 and March 15, 2005.

Environmental Conditions:

QAPP Information:

The data meet the quality assurance requirements of the SWAMP QAPP.

QAPP Information Reference(s):


DECISION ID	73735	Region 6
Amargosa River (Tecopa to Upper Canyon)

Pollutant:	Cobalt
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2016)
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Staff Conclusion:	This pollutant is being considered for placement on the CWA section 303(d) List under section 3.2 of the Listing Policy. Under section 3.2 a single line of evidence is necessary to assess listing status. Four lines of evidence are available in the administrative record to assess this pollutant, three for inland saline habitat and one for AGR. The lines of evidence from 2010 do not include an objective or criteria to assess the cobalt data so the decision exceedance count is for the 2018 line of evidence for AGR. Zero of one samples exceed the AGR guideline for cobalt. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the CWA section 303(d) List. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. Zero of one samples exceeded the guideline and this does not exceed the allowable frequency listed in Table 3.2 of the Listing Policy. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

Regional Board Staff Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.

Line of Evidence (LOE) for Decision ID 73735, Cobalt	Region 6
Amargosa River (Tecopa to Upper Canyon)

LOE ID:

98940

Pollutant:

Cobalt

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Agricultural Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for the USGS National Water Information System.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Waters designated as AGR shall not contain concentrations of chemical constituents in amounts that adversely affect the water for beneficial uses (Water Quality Control Plan, Lahontan Region).

Objective/Criterion Reference:

Water Quality Control Plan for the Lahontan Region (as amended)

Evaluation Guideline:

Water Quality for Agriculture, published by the Food and Agriculture Organization of the United Nations in 1985, contains criteria protective of various agricultural uses of water. These criteria were used to translate narrative water quality objectives for chemical constituents that prohibit chemicals in concentrations that would impair agricultural uses of water. A 0.05 mg/L criteria is the recommended maximum concentration of cobalt in irrigation water.

Guideline Reference:

Water Quality for Agriculture, Food and Agriculture Organization of the United Nations - Irrigation and Drainage Paper No. 29, Rev 1, Rome (1985)

Spatial Representation:

The samples were collected at 1 monitoring site(s) (USGS-10251300)

Temporal Representation:

The samples were collected between the dates of 2014-03-27 and 2014-03-27

Environmental Conditions:

QAPP Information:

QAPP not required for federal data

QAPP Information Reference(s):

This is a placeholder reference for data which does not require a QAPP.

Line of Evidence (LOE) for Decision ID 73735, Cobalt	Region 6
Amargosa River (Tecopa to Upper Canyon)

LOE ID:

25013

Pollutant:

Cobalt

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Inland Saline Water Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

The U.S. Geological Survey sampled this station on March 17, 2004 and March 15, 2005 under the Region 6 SWAMP program. Two samples had total cobalt concentrations of 0.46 and 0.51 ug/L.

Data Reference:

2007. SWAMP Data for the Amargosa Hydrologic Unit

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

There are no applicable state or federal saltwater aquatic life standards or criteria for total cobalt for inland saline waters.

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

One station, Amargosa River at Upper Canyon, was sampled.

Temporal Representation:

Two samples were collected on March 17, 2004 and March 15, 2005.

Environmental Conditions:

QAPP Information:

The data meet the quality assurance requirements of the SWAMP QAPP.

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 73735, Cobalt	Region 6
Amargosa River (Tecopa to Upper Canyon)

LOE ID:

24860

Pollutant:

Cobalt

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

None

Beneficial Use:

Inland Saline Water Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Chemical monitoring of sediments

Data Used to Assess Water Quality:

Data Reference:

2007. SWAMP Data for the Amargosa Hydrologic Unit

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

There are no state or federal standards or criteria for cobalt in sediment in inland saline waters.

Objective/Criterion Reference:

Water Quality Control Plan for the Lahontan Region (as amended)

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

One station, Amargosa River at Upper Canyon, was sampled.

Temporal Representation:

One sediment sample was collected on March 15, 2005.

Environmental Conditions:

QAPP Information:

The data meet the quality assurance requirements of the SWAMP QAPP.

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 73735, Cobalt	Region 6
Amargosa River (Tecopa to Upper Canyon)

LOE ID:

25012

Pollutant:

Cobalt

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Inland Saline Water Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

The U.S. Geological Survey sampled this station on March 17, 2004 and March 15, 2005 under the Region 6 SWAMP program. Two samples had dissolved cobalt concentrations of 0.15 and 0.2 ug/L.

Data Reference:

2007. SWAMP Data for the Amargosa Hydrologic Unit

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

There are no applicable state or federal saltwater aquatic life standards or criteria for cobalt for inland saline waters.

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

One station, Amargosa River at Upper Canyon, was sampled.

Temporal Representation:

Two samples were collected on March 17, 2004 and March 15, 2005.

Environmental Conditions:

QAPP Information:

The data meet the quality assurance requirements of the SWAMP QAPP.

QAPP Information Reference(s):


DECISION ID	73703	Region 6
Amargosa River (Tecopa to Upper Canyon)

Pollutant:	Indicator Bacteria
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2016)
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Staff Conclusion:	Regional Board conclusion: This pollutant was considered for placement on the section 303(d) list in a previous assessment cycle. No new informatoin was reviewed for this current assessment cycle. Therefore, the previous conclusion remains unchanged, and is as follows: This pollutant is being considered for placement on the section 303(d) list under section 3.3 of the Listing Policy. Under section 3.3 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. The single sample is an estimated value. 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 satisfy the data quality requirements of section 6.1.4 of the Policy. 2. The single sample does not satisfy the data quantity requirements of section 6.1.5 of the Policy. 3. The single sample (an estimated value) does not meet the minimum sample number requirements of 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 Staff Decision Recommendation:	This region was not assessed this cycle. All decisions have been carried over from the previous cycle and remain the same.

Line of Evidence (LOE) for Decision ID 73703, Indicator Bacteria	Region 6
Amargosa River (Tecopa to Upper Canyon)

LOE ID:

25182

Pollutant:

Fecal Coliform

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Water Contact Recreation

Number of Samples:

Number of Exceedances:

Data and Information Type:

Water column surveys (e.g. fecal coliform)

Data Used to Assess Water Quality:

The U.S. Geological Survey sampled this station on March 17, 2004 under the Region 6 SWAMP program. The fecal coliform count in a single sample was an estimated value.

Data Reference:

2007. SWAMP Data for the Amargosa Hydrologic Unit

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The Lahontan Basin Plan's objective for coliform bacteria states: "Waters shall not contain concentrations of coliform organisms attributable to anthropogenic sources, including human and livestock wastes. The fecal coliform concentration during any 30-day period shall not exceed a log mean of 20/100 ml, nor shall more than 10 percent of all samples collected during any 30-day period exceed 40/100 ml. The log mean shall ideally be based on a minimum of not less than five samples collected as evenly spaced as practicable during any 30-day period. However, a log mean concentration exceeding 20/100 ml for any 30-day period shall indicate violation of this objective even if fewer than five samples were collected."

Objective/Criterion Reference:

Water Quality Control Plan for the Lahontan Region (as amended)

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

One station, Amargosa River at Upper Canyon, was sampled.

Temporal Representation:

One sample was taken on March 17, 2004.

Environmental Conditions:

QAPP Information:

The data meet the quality assurance requirements of the SWAMP QAPP.

QAPP Information Reference(s):


DECISION ID	73518	Region 6
Amargosa River (Tecopa to Upper Canyon)

Pollutant:	Iron
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2016)
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Staff Conclusion:	This pollutant is being considered for placement on the CWA section 303(d) List under section 3.1 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status. Four lines of evidence are available in the administrative record to assess this pollutant, three from a previous cycle that assess for inland saline habitat and one for WARM. The lines of evidence from 2010 do not include an assessment objective or criteria for iron so the decision exceedance count is based on the WARM line of evidence from 2018. Zero of one samples exceed the guideline for iron. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the CWA section 303(d) List in the Water Quality Limited Segments category. This conclusion is based on the staff findings that: 1. The data used 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 one samples exceed the guideline 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 Staff Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.

Line of Evidence (LOE) for Decision ID 73518, Iron	Region 6
Amargosa River (Tecopa to Upper Canyon)

LOE ID:

25000

Pollutant:

Iron

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Inland Saline Water Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

The U.S. Geological Survey sampled this station on March 17, 2004 and March 15, 2005 under the Region 6 SWAMP program. One of two samples for dissolved iron was an estimated value and the iron concentration in the other was 20 ug/L.

Data Reference:

2007. SWAMP Data for the Amargosa Hydrologic Unit

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

There are no applicable state or federal saltwater aquatic life standards or criteria for dissolved iron in inland saline waters.

Objective/Criterion Reference:

Water Quality Control Plan for the Lahontan Region (as amended)

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

One station, Amargosa River at Upper Canyon, was sampled.

Temporal Representation:

Two samples were collected on March 17, 2004 and March 15, 2005.

Environmental Conditions:

QAPP Information:

The data meet the quality assurance requirements of the SWAMP QAPP.

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 73518, Iron	Region 6
Amargosa River (Tecopa to Upper Canyon)

LOE ID:

98952

Pollutant:

Iron

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for the USGS National Water Information System.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan for the Lahontan Region (as amended)

Evaluation Guideline:

The Red Book states that based on field observations principally, a criterion of 1.0 mg/L iron for freshwater aquatic life is believed to be adequately protective.

Guideline Reference:

Quality Criteria for Water. USEPA Office of Water and Hazardous Materials. Washington, D.C

Spatial Representation:

The samples were collected at 1 monitoring site(s) (USGS-10251300)

Temporal Representation:

The samples were collected between the dates of 2014-03-27 and 2014-03-27

Environmental Conditions:

QAPP Information:

QAPP not required for federal data

QAPP Information Reference(s):

This is a placeholder reference for data which does not require a QAPP.

Line of Evidence (LOE) for Decision ID 73518, Iron	Region 6
Amargosa River (Tecopa to Upper Canyon)

LOE ID:

25004

Pollutant:

Iron

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Inland Saline Water Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

The U.S. Geological Survey sampled this station on March 17, 2004 and March 15, 2005 under the Region 6 SWAMP program. Two samples had total iron concentrations of 620 and 220 ug/L.

Data Reference:

2007. SWAMP Data for the Amargosa Hydrologic Unit

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

There are no applicable state or federal saltwater aquatic life standards or criteria for total iron in inland saline waters.

Objective/Criterion Reference:

Water Quality Control Plan for the Lahontan Region (as amended)

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

One station, Amargosa River at Upper Canyon, was sampled.

Temporal Representation:

Two samples were collected on March 17, 2004 and March 15, 2005.

Environmental Conditions:

QAPP Information:

The data meet the quality assurance requirements of the SWAMP QAPP.

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 73518, Iron	Region 6
Amargosa River (Tecopa to Upper Canyon)

LOE ID:

24865

Pollutant:

Iron

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

None

Beneficial Use:

Inland Saline Water Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Chemical monitoring of sediments

Data Used to Assess Water Quality:

Data Reference:

2007. SWAMP Data for the Amargosa Hydrologic Unit

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

There are no state or federal standards or criteria for iron in sediment in inland saline waters.

Objective/Criterion Reference:

Water Quality Control Plan for the Lahontan Region (as amended)

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

One station, Amargosa River at Upper Canyon, was sampled.

Temporal Representation:

One sediment sample was collected on March 15, 2005.

Environmental Conditions:

QAPP Information:

The data meet the quality assurance requirements of the SWAMP QAPP.

QAPP Information Reference(s):


DECISION ID	73682	Region 6
Amargosa River (Tecopa to Upper Canyon)

Pollutant:	Molybdenum
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2016)
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Staff Conclusion:	This pollutant is being considered for placement on the CWA section 303(d) List under section 3.1 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status. Four lines of evidence are available in the administrative record to assess this pollutant, three from a previous cycle that assess for inland saline habitat and one that assesses for AGR. The lines of evidence from 2010 do not include an assessment criteria or objective for molybdenum so the decision exceedance count is based on the 2018 AGR line of evidence. One of one samples exceed the guideline for molybdenum. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the CWA section 303(d) List in the Water Quality Limited Segments category. This conclusion is based on the staff findings that: 1. The data used 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 one samples exceeded the guideline 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 Staff Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.

Line of Evidence (LOE) for Decision ID 73682, Molybdenum	Region 6
Amargosa River (Tecopa to Upper Canyon)

LOE ID:

25026

Pollutant:

Molybdenum

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Inland Saline Water Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

The U.S. Geological Survey sampled this station on March 17, 2004 and March 15, 2005 under the Region 6 SWAMP program. The concentrations of total molybdenum in two samples were 38.2 and 39.8 ug/L

Data Reference:

2007. SWAMP Data for the Amargosa Hydrologic Unit

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

There are no applicable state or federal saltwater aquatic life standards or criteria for total molybdenum in inland saline waters.

Objective/Criterion Reference:

Water Quality Control Plan for the Lahontan Region (as amended)

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

One station, Amargosa River at Upper Canyon, was sampled.

Temporal Representation:

Two samples were collected on March 17, 2004 and March 15, 2005.

Environmental Conditions:

QAPP Information:

The data meet the quality assurance requirements of the SWAMP QAPP.

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 73682, Molybdenum	Region 6
Amargosa River (Tecopa to Upper Canyon)

LOE ID:

24869

Pollutant:

Molybdenum

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

None

Beneficial Use:

Inland Saline Water Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Chemical monitoring of sediments

Data Used to Assess Water Quality:

Data Reference:

2007. SWAMP Data for the Amargosa Hydrologic Unit

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

There are no state or federal standards or criteria for molybdenum in sediment in inland saline waters.

Objective/Criterion Reference:

Water Quality Control Plan for the Lahontan Region (as amended)

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

One station, Amargosa River at Upper Canyon, was sampled.

Temporal Representation:

One sediment sample was collected on March 15, 2005.

Environmental Conditions:

QAPP Information:

The data meet the quality assurance requirements of the SWAMP QAPP.

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 73682, Molybdenum	Region 6
Amargosa River (Tecopa to Upper Canyon)

LOE ID:

25027

Pollutant:

Molybdenum

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Inland Saline Water Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

The U.S. Geological Survey sampled this station on March 17, 2004 and March 15, 2005 under the Region 6 SWAMP program. The concentrations of dissolved molybdenum in two samples were 39.1 and 40.6 ug/L

Data Reference:

2007. SWAMP Data for the Amargosa Hydrologic Unit

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

There are no applicable state or federal saltwater aquatic life standards or criteria for dissolved molybdenum in inland saline waters.

Objective/Criterion Reference:

Water Quality Control Plan for the Lahontan Region (as amended)

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

One station, Amargosa River at Upper Canyon, was sampled.

Temporal Representation:

Two samples were collected on March 17, 2004 and March 15, 2005.

Environmental Conditions:

QAPP Information:

The data meet the quality assurance requirements of the SWAMP QAPP.

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 73682, Molybdenum	Region 6
Amargosa River (Tecopa to Upper Canyon)

LOE ID:

98901

Pollutant:

Molybdenum

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Agricultural Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for the USGS National Water Information System.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Waters designated as AGR shall not contain concentrations of chemical constituents in amounts that adversely affect the water for beneficial uses (Water Quality Control Plan, Lahontan Region).

Objective/Criterion Reference:

Water Quality Control Plan for the Lahontan Region (as amended)

Evaluation Guideline:

Water Quality for Agriculture, published by the Food and Agriculture Organization of the United Nations in 1985, contains criteria protective of various agricultural uses of water. These criteria were used to translate narrative water quality objectives for chemical constituents that prohibit chemicals in concentrations that would impair agricultural uses of water. The 0.01 mg/L criteria is the recommended maximum concentration of molybdenum in irrigation water.

Guideline Reference:

Water Quality for Agriculture, Food and Agriculture Organization of the United Nations - Irrigation and Drainage Paper No. 29, Rev 1, Rome (1985)

Spatial Representation:

The samples were collected at 1 monitoring site(s) (USGS-10251300)

Temporal Representation:

The samples were collected between the dates of 2014-03-27 and 2014-03-27

Environmental Conditions:

QAPP Information:

QAPP not required for federal data

QAPP Information Reference(s):

This is a placeholder reference for data which does not require a QAPP.


DECISION ID	73183	Region 6
Amargosa River (Tecopa to Upper Canyon)

Pollutant:	Nitrogen, Nitrite
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2016)
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Staff Conclusion:	Regional Board conclusion: This pollutant was considered for placement on the section 303(d) list in a previous assessment cycle. No new information was reviewed for this current assessment cycle. Therefore, the previous conclusion remains unchanged, and is as follows: 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 biological data are available for assessment whether any of the chemical samples exceeds 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 satisfy the data quality requirements of section 6.1.4 of the Policy. 2. The data used do not satisfy the data quantity requirements of section 6.1.5 of the Policy (only one sample per year is available). 3. No biological data are available for assessment of compliance with the objective and the data cannot be evaluated using 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 Staff Decision Recommendation:	This region was not assessed this cycle. All decisions have been carried over from the previous cycle and remain the same.

Line of Evidence (LOE) for Decision ID 73183, Nitrogen, Nitrite	Region 6
Amargosa River (Tecopa to Upper Canyon)

LOE ID:

25179

Pollutant:

Nitrite as Nitrite NO2

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Inland Saline Water Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

The U.S. Geological Survey sampled this station on March 17, 2004 and March 15, 2005 under the Region 6 SWAMP program. Two samples had nitrite concentrations of 0.001 and 0.002 mg/L.

Data Reference:

2007. SWAMP Data for the Amargosa Hydrologic Unit

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

There are no applicable state or federal saltwater aquatic life standards or criteria for nitrite. The Lahontan Basin Plan's regionwide objective for biostimulatory substances states: "Waters shall not contain biostimulatory substances in concentrations that promote aquatic growths to the extent that such growths cause nuisance or adversely affect the water for beneficial uses."

Objective/Criterion Reference:

Water Quality Control Plan for the Lahontan Region (as amended)

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

One station, Amargosa River at Upper Canyon, was sampled.

Temporal Representation:

Two samples were taken on March 17, 2004 and March 15, 2005.

Environmental Conditions:

QAPP Information:

The data meet the quality assurance requirements of the SWAMP QAPP.

QAPP Information Reference(s):


DECISION ID	73329	Region 6
Amargosa River (Tecopa to Upper Canyon)

Pollutant:	Selenium
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2016)
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Staff Conclusion:	Regional Board conclusion: This pollutant was considered for placement on the section 303(d) list in a previous assessment cycle. No new information was reviewed for this current assessment cycle. Therefore, the previous conclusion remains unchanged, and is as follows: 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. Three lines of evidence, consisting of one or two samples each, are available in the administrative record to assess this pollutant. There are no applicable saltwater aquatic life standards or criteria for selenium in inland saline waters. The California Toxics Rule standards, based on toxicity to marine/estuarine organisms, were not exceeded. 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 satisfy the data quality requirements of section 6.1.4 of the Policy. 2. The sediment data used do not satisfy the data quantity requirements of section 6.1.5 of the Policy. 3. There are no applicable water quality standards or criteria for inland saline waters. The two dissolved selenium samples did not exceed the California Toxics Rule standards, and this does not exceed the allowable frequency in Listing Policy Table 3.1. The single sediment sample did not meet the minimum sample number requirements 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 Staff Decision Recommendation:	This region was not assessed this cycle. All decisions have been carried over from the previous cycle and remain the same.

Line of Evidence (LOE) for Decision ID 73329, Selenium	Region 6
Amargosa River (Tecopa to Upper Canyon)

LOE ID:

25031

Pollutant:

Selenium

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Inland Saline Water Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

The U.S. Geological Survey sampled this station on March 17, 2004 and March 15, 2005 under the Region 6 SWAMP program. One of two samples for total selenium was below the detection level and the concentration in the other was 1.4 ug/L.

Data Reference:

2007. SWAMP Data for the Amargosa Hydrologic Unit

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

There are no applicable state or federal saltwater aquatic life standards or criteria for total selenium in inland surface waters.

Objective/Criterion Reference:

Water Quality Control Plan for the Lahontan Region (as amended)

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

One station, Amargosa River at Upper Canyon, was sampled.

Temporal Representation:

Two samples were collected on March 17, 2004 and March 15, 2005.

Environmental Conditions:

QAPP Information:

The data meet the quality assurance requirements of the SWAMP QAPP.

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 73329, Selenium	Region 6
Amargosa River (Tecopa to Upper Canyon)

LOE ID:

24873

Pollutant:

Selenium

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

None

Beneficial Use:

Inland Saline Water Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Chemical monitoring of sediments

Data Used to Assess Water Quality:

Data Reference:

2007. SWAMP Data for the Amargosa Hydrologic Unit

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

There are no state or federal standards or criteria for selenium in sediment in inland saline waters.

Objective/Criterion Reference:

Water Quality Control Plan for the Lahontan Region (as amended)

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

One station, Amargosa River at Upper Canyon, was sampled.

Temporal Representation:

One sediment sample was collected on March 15, 2005.

Environmental Conditions:

QAPP Information:

The data meet the quality assurance requirements of the SWAMP QAPP.

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 73329, Selenium	Region 6
Amargosa River (Tecopa to Upper Canyon)

LOE ID:

25030

Pollutant:

Selenium

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Inland Saline Water Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

The U.S. Geological Survey sampled this station on March 17, 2004 and March 15, 2005 under the Region 6 SWAMP program. One of two samples for dissolved selenium was an estimated value and the concentration in the other was 1 ug/L.

Data Reference:

2007. SWAMP Data for the Amargosa Hydrologic Unit

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The Califonia Toxics Rule standards for dissolved selenium include an acute toxicity limit of 290 ug/L and a chronic toxicity limit of 71 ug/L.

Objective/Criterion Reference:

Water Quality Control Plan for the Lahontan Region (as amended)

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

One station, Amargosa River at Upper Canyon, was sampled.

Temporal Representation:

Two samples were collected on March 17, 2004 and March 15, 2005.

Environmental Conditions:

QAPP Information:

The data meet the quality assurance requirements of the SWAMP QAPP.

QAPP Information Reference(s):


DECISION ID	76589	Region 6
Amargosa River (Tecopa to Upper Canyon)

Pollutant:	Sodium
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2016)
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Staff Conclusion:	This pollutant is being considered for placement on the CWA section 303(d) List under section 3.2 of the Listing Policy. Under section 3.2 a single line of evidence is necessary to assess listing status. Three lines of evidence are available in the administrative record to assess this pollutant, two from a previous cycle that assess for inland saline habitat and one that assesses for AGR. The lines of evidence for inland saline habitat from 2010 do not include an assessment guideline or objective for sodium so the decision exceedance count is based on the 2018 AGR line of evidence. One of one samples exceed the AGR guideline for sodium. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the CWA section 303(d) List. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3.One of one samples exceed the AGR guideline and this does not exceed the allowable frequency listed in Table 3.2 of the Listing Policy. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

Regional Board Staff Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.

Line of Evidence (LOE) for Decision ID 76589, Sodium	Region 6
Amargosa River (Tecopa to Upper Canyon)

LOE ID:

25169

Pollutant:

Sodium

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Inland Saline Water Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

The U.S. Geological Survey sampled this station on March 17, 2004 and March 15, 2005 under the Region 6 SWAMP program. Two samples had dissolved sodium concentrations of 878 and 660 mg/L.

Data Reference:

2007. SWAMP Data for the Amargosa Hydrologic Unit

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

There are no state or federal saltwater aquatic life standards or criteria for dissolved sodium in inland saline waters.

Objective/Criterion Reference:

Water Quality Control Plan for the Lahontan Region (as amended)

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

One station, Amargosa River at Upper Canyon, was sampled.

Temporal Representation:

Two samples were taken on March 17, 2004 and March 15, 2005.

Environmental Conditions:

QAPP Information:

The data meet the quality assurance requirements of the SWAMP QAPP.

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 76589, Sodium	Region 6
Amargosa River (Tecopa to Upper Canyon)

LOE ID:

98827

Pollutant:

Sodium

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Agricultural Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for the USGS National Water Information System.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life (Water Quality Control Plan, Lahontan Region).

Objective/Criterion Reference:

Water Quality Control Plan for the Lahontan Region (as amended)

Evaluation Guideline:

Water Quality for Agriculture, published by the Food and Agriculture Organization of the United Nations in 1985, contains criteria protective of various agricultural uses of water, including irrigation of various types of crops and stock watering. At or below the sodium threshold of 69 mg/L, agricultural uses of water should not be limited.

Guideline Reference:

Water Quality for Agriculture, Food and Agriculture Organization of the United Nations - Irrigation and Drainage Paper No. 29, Rev 1, Rome (1985)

Spatial Representation:

The samples were collected at 1 monitoring site(s) (USGS-10251300)

Temporal Representation:

The samples were collected between the dates of 2014-03-27 and 2014-03-27

Environmental Conditions:

QAPP Information:

QAPP not required for federal data

QAPP Information Reference(s):

This is a placeholder reference for data which does not require a QAPP.

Line of Evidence (LOE) for Decision ID 76589, Sodium	Region 6
Amargosa River (Tecopa to Upper Canyon)

LOE ID:

24847

Pollutant:

Sodium

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

None

Beneficial Use:

Inland Saline Water Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Chemical monitoring of sediments

Data Used to Assess Water Quality:

Data Reference:

2007. SWAMP Data for the Amargosa Hydrologic Unit

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

There are no state or federal standards or criteria for sodium in sediment in inland saline waters.

Objective/Criterion Reference:

Water Quality Control Plan for the Lahontan Region (as amended)

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

One station, Amargosa River at Upper Canyon, was sampled.

Temporal Representation:

One sediment sample was collected on March 15, 2005.

Environmental Conditions:

QAPP Information:

The data meet the quality assurance requirements of the SWAMP QAPP.

QAPP Information Reference(s):


DECISION ID	73533	Region 6
Amargosa River (Tecopa to Upper Canyon)

Pollutant:	1, 1, 2-trichloro-1, 2, 2-trifluoroethane \| 1, 1-dichloroethane \| 2, 4 D methyl ester / 2,4-Dichlorophenoxyacetic acid methyl ester \| 2, 4 DB / 4-(2,4-dichlorophenoxy) butyric acid \| 2,4-D (2,4-Dichlorophenoxy acetic acid) \| 2-Methyl-4-chlorophenoxyacetic acid (MCPA):acetic acid \| 2-chloro-4-isopropylamino-6-amino-s-triazine \| 2-chloro-6-ethylamino-4-amino-s-triazine \| 3-ketocarbofuran \| 4(4 chloro-2-methyl phenoxy (MCPB)) butanoic acid \| Aciflorfen \| Aldicarb \| Aldicarb sulfone \| Aldicarb sulfoxide \| Bendiocarb \| Benomyl \| Bensulfuron \| Bentazon \| Bromacil \| Bromoxynil \| Carbofuran \| Chloramben methyl ester \| Chlorimuron \| Chlorodiamino-s-triazine \| Chloropyralid \| Chlorothalonil \| Cycloate \| Dacthal monoacid \| Dicamba \| Dichloroprop \| Diethyl ether \| Diisopropyl ether \| Dinoseb \| Diphenamid \| Diuron \| Fenuron \| Flometuron \| Flumetsulam \| Hydroxyl carbofuran \| Imazaquin \| Imazethapyr \| Imidacloprid \| Linuron \| Metalaxyl \| Methiocarb \| Methomyl \| Methyl tert-pentyl ether \| Metsulfuron \| N-(4-Chlorophenyl) -N' methylurea / Monuron \| Neburon \| Nicosulfuron \| Norflurazon \| Oryzalin \| Oxamyl (Vydate) \| Picloram \| Propham \| Propiconazol \| Propoxur \| Siduron \| Styrene \| Sulfometuron \| Tebuthiuron \| Terbacil \| Tert-butyl ethyl ether \| Triazone \| Tribenuron \| Vinyl chloride \| meta-para xylenes \| o-Xylene
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2016)
Revision Status	Original
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Staff Conclusion:	Regional Board conclusion: This pollutant was considered for placement on the section 303(d) list in a previous assessment cycle. No new information was reviewed for this current assessment cycle. Therefore, the previous conclusion remains unchanged, and is as follows: 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. There are no applicable water quality standards or criteria for any of the listed pollutants.. 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 satisfy the data quality requirements of section 6.1.4 of the Policy. 2. The single sampling result available for each pollutant does not satisfy the data quantity requirements of section 6.1.5 of the Policy. 3. There are no applicable water quality standards or criteria and the data cannot be assessed using 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 Staff Decision Recommendation:	This region was not assessed this cycle. All decisions have been carried over from the previous cycle and remain the same.

Line of Evidence (LOE) for Decision ID 73533, Multiple Pollutants	Region 6
Amargosa River (Tecopa to Upper Canyon)

LOE ID:

25225

Pollutant:

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Inland Saline Water Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

The U.S. Geological Survey sampled organic chemicals at this station on March 17, 2004 under the Region 6 SWAMP program. One sampling result was reported for each of the listed pollutants. All of these pollutants were below the detection level.

Data Reference:

2007. SWAMP Data for the Amargosa Hydrologic Unit

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

There are no applicable state or federal saltwater standards or criteria for the listed pollutants.

Objective/Criterion Reference:

Water Quality Control Plan for the Lahontan Region (as amended)

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

One station, Amargosa River at Upper Canyon, was sampled.

Temporal Representation:

One sampling result was reported for each of the listed pollutants from a sample or samples collected on March 17, 2004

Environmental Conditions:

QAPP Information:

The data meet the quality assurance requirements of the SWAMP QAPP.

QAPP Information Reference(s):


DECISION ID	74064	Region 6
Amargosa River (Tecopa to Upper Canyon)

Pollutant:	1, 3 -dichlorobenzene \| 1, 4 -dichlorobenzene \| 1,1,1-Trichloroethane \| 1,1-Dichloroethylene (DCE)/ Vinylidene Chloride \| 1,2-Dichloroethylene,-trans \| 1,2-Dichloropropane \| Atrazine \| Benzene \| Bromoform \| Carbaryl \| Carbon tetrachloride \| Chlorobenzene (mono) \| Chlorodibromomethane \| Chloroform \| Dichlorobromomethane \| Dichlorodifluoromethane \| Dichloromethane \| Ethylbenzene \| Methyl Tertiary-Butyl Ether (MTBE) \| Tetrachloroethylene/PCE \| Toluene \| Trichloroethene \| Trichlorofluoromethane (CFC-11) \| cis-1,2-Dichloroethylene
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2016)
Revision Status	Original
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Staff Conclusion:	Regional Board conclusion: This pollutant was considered for placement on the section 303(d) list in a previous assessment cycle. No new information was reviewed for this current assessment cycle. Therefore, the previous conclusion remains unchanged, and is as follows: This pollutants are 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. All of the pollutants were at non-detectable levels. Under Section 6.1.5.5 of the Listing Policy, the appiicable standards are presumed to be attained.. 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 satisfy the data quality requirements of section 6.1.4 of the Policy. 2. The single sample available for each pollutant does not satisfy the data quantity requirements of section 6.1.5 of the Policy. 3. None of the single samples for each pollutant exceeded the applicable standards and this does not exceed the allowable frequency 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 Staff Decision Recommendation:	This region was not assessed this cycle. All decisions have been carried over from the previous cycle and remain the same.

Line of Evidence (LOE) for Decision ID 74064, Multiple Pollutants	Region 6
Amargosa River (Tecopa to Upper Canyon)

LOE ID:

25412

Pollutant:

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Inland Saline Water Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

The U.S. Geological Survey sampled this station on March 17, 2004. Concentrations of the listed pollutants were all below the detection level.

Data Reference:

2007. SWAMP Data for the Amargosa Hydrologic Unit

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

(In the following summary of criteria, when a single concentration is listed, it is the acute toxicity limit. When two concentrations are listed, the first number is the acute toxicity limit and the second is the chronic toxicity limit.
U.S. Environmental Protection Agency (USEPA) national recommended saltwater aquatic life criteria for the following pollutants are as follows: atrazine, 760 ug/L/17 ug/L; carbaryl, 0.81 ug/L/0.81 ug/L; methyl tertiary butyl ether (MTBE), 53,000 ug/L/ 18,000 ug/L. The USEPA saltwater "Lowest Observed Effect Level" (LOEL) criteria are as follows: 1, 1, 1 trichloroethane, 31,200 ug/L; 1,1 dichloroethene, 224, 000 ug/L; 1, 2 dichloropropane, 10,300 ug/L; 1, 3 dichlorobenzene, 1970 ug/L/129 ug/L; 1, 4 dichlorobenzene, 1970 ug/L/ 129 ug/L; benzene, 5100 ug/L; bromodichloromethane, 12,000 ug/L/6400 ug/L; chlorobenzene 160 ug/L/129 ug/L;

Objective/Criterion Reference:

Water Quality Control Plan for the Lahontan Region (as amended)

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

One station, Amargosa River at USGS Gage (Tecopa) was sampled.

Temporal Representation:

One sample for each of the 24 listed pollutants was collected on March 17, 2004.

Environmental Conditions:

QAPP Information:

The data meet the quality assurance requirements of the SWAMP QAPP.

QAPP Information Reference(s):


DECISION ID	70968	Region 6
Amargosa River (Tecopa to Upper Canyon)

Pollutant:	Alkalinity as CaCO3
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2016)
Revision Status	Original
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Staff Conclusion:	Regional Board conclusion: This pollutant was considered for placement on the section 303(d) list in a previous assessment cycle. No new information was reviewed for this current asessment cycle. Therefore, the previous conclusion remains unchanged, and is as follows: 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. There are no applicable water quality standards or criteria. 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 satisfy the data quality requirements of section 6.1.4 of the Policy. 2. The data used do not satisfy the data quantity requirements of section 6.1.5 of the Policy. (Only one sample per year was collected.) 3. There are no applicable water quality standards or criteria and the data cannot be assessed using 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 Staff Decision Recommendation:	This region was not assessed this cycle. All decisions have been carried over from the previous cycle and remain the same.

Line of Evidence (LOE) for Decision ID 70968, Alkalinity as CaCO3	Region 6
Amargosa River (Tecopa to Upper Canyon)

LOE ID:

27056

Pollutant:

Alkalinity as CaCO3

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Inland Saline Water Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

The U.S. Geological Survey sampled this station on March 17, 2004 and March 15, 2005 under the Region 6 SWAMP program. Two samples had alkalinities of 616 and 580 mg/L CaCO3. The criterion was not violated.

Data Reference:

2007. SWAMP Data for the Amargosa Hydrologic Unit

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The USEPA's national water quality criteria recommend a minimum hardness of 20 mg/L calcium carbonate as a chronic criterion for the protection of freshwater aquatic life, unless the natural alkalinity level is lower. There are no applicable water quality standards or criteria for alkalinity in inland saline waters.

Objective/Criterion Reference:

Water Quality Control Plan for the Lahontan Region (as amended)

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

One station, Amargosa River at Upper Canyon, was sampled.

Temporal Representation:

Two samples were taken on March 17, 2004 and March 15, 2005.

Environmental Conditions:

QAPP Information:

The data meet the quality assurance requirements of the SWAMP QAPP.

QAPP Information Reference(s):


DECISION ID	73070	Region 6
Amargosa River (Tecopa to Upper Canyon)

Pollutant:	Aluminum
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2016)
Revision Status	Original
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Staff Conclusion:	id Regional Board conclusion: This pollutant was considered for placement on the section 303(d) list in a previous assessment cycle. No new information was reviewed for this current assessment cycle. Therefore, the previous conclusion remains unchanged, and is as follows: 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. Three lines of evidence, consisting of one or two samples each, are available in the administrative record to assess this pollutant. There are no applicable saltwater aquatic life standards or criteria for aluminum in inland saline waters. 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 satisfy the data quality requirements of section 6.1.4 of the Policy. 2. The sediment data used do not satisfy the data quantity requirements of section 6.1.5 of the Policy. 3. There are no applicable water quality standards or criteria and the data cannot be assessed using 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 Staff Decision Recommendation:	This region was not assessed this cycle. All decisions have been carried over from the previous cycle and remain the same.

Line of Evidence (LOE) for Decision ID 73070, Aluminum	Region 6
Amargosa River (Tecopa to Upper Canyon)

LOE ID:

24992

Pollutant:

Aluminum

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Inland Saline Water Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

The U.S. Geological Survey sampled this station on March 17, 2004 and March 15, 2005 under the Region 6 SWAMP program. Two samples had dissolved aluminum concentrations below the detection level.

Data Reference:

2007. SWAMP Data for the Amargosa Hydrologic Unit

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

There are no applicable state or federal saltwater aquatic life standards or criteria for dissolved aluminum in inland saline waters.

Objective/Criterion Reference:

Water Quality Control Plan for the Lahontan Region (as amended)

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

One station, Amargosa River at Upper Canyon, was sampled.

Temporal Representation:

Two samples were collected on March 17, 2004 and March 15, 2005.

Environmental Conditions:

QAPP Information:

The data meet the quality assurance requirements of the SWAMP QAPP.

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 73070, Aluminum	Region 6
Amargosa River (Tecopa to Upper Canyon)

LOE ID:

24843

Pollutant:

Aluminum

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

None

Beneficial Use:

Inland Saline Water Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Chemical monitoring of sediments

Data Used to Assess Water Quality:

Data Reference:

2007. SWAMP Data for the Amargosa Hydrologic Unit

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

There are no state or federal standards or criteria for aluminum in sediment in inland saline waters.

Objective/Criterion Reference:

Water Quality Control Plan for the Lahontan Region (as amended)

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

One station, Amargosa River at Upper Canyon, was sampled.

Temporal Representation:

One sediment sample was collected on March 15, 2005.

Environmental Conditions:

QAPP Information:

The data meet the quality assurance requirements of the SWAMP QAPP.

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 73070, Aluminum	Region 6
Amargosa River (Tecopa to Upper Canyon)

LOE ID:

24993

Pollutant:

Aluminum

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Inland Saline Water Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

The U.S. Geological Survey sampled this station on March 17, 2004 and March 15, 2005 under the Region 6 SWAMP program. The concentrations of total aluminum in two samples were 528 and 228 ug/L.

Data Reference:

2007. SWAMP Data for the Amargosa Hydrologic Unit

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

There are no applicable state or federal saltwater aquatic life standards or criteria for total aluminum in inland saline waters.

Objective/Criterion Reference:

Water Quality Control Plan for the Lahontan Region (as amended)

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

One station, Amargosa River at Upper Canyon, was sampled.

Temporal Representation:

Two samples were collected on March 17, 2004 and March 15, 2005.

Environmental Conditions:

QAPP Information:

The data meet the quality assurance requirements of the SWAMP QAPP.

QAPP Information Reference(s):


DECISION ID	73410	Region 6
Amargosa River (Tecopa to Upper Canyon)

Pollutant:	Barium
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2016)
Revision Status	Original
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Staff Conclusion:	Regional Board conclusion: This pollutant was considered for placement on the section 303(d) list in a previous assessment cycle. No new information was reviewed for this current assessment cycle. Therefore, the previous conclusion remains unchanged, and is as follows: 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, consisting of a single sediment sample, is available in the administrative record to assess this pollutant. There are no applicable water quality standards or criteria for barium in sediment of inland saline waters. 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 satisfy the data quality requirements of section 6.1.4 of the Policy. 2. The data used do not satisfy the data quantity requirements of section 6.1.5 of the Policy. 3. There are no applicable water quality standards or criteria and the single sample cannot be assessed using 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 Staff Decision Recommendation:	This region was not assessed this cycle. All decisions have been carried over from the previous cycle and remain the same.

Line of Evidence (LOE) for Decision ID 73410, Barium	Region 6
Amargosa River (Tecopa to Upper Canyon)

LOE ID:

24853

Pollutant:

Barium

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

None

Beneficial Use:

Inland Saline Water Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Chemical monitoring of sediments

Data Used to Assess Water Quality:

Data Reference:

2007. SWAMP Data for the Amargosa Hydrologic Unit

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

There are no state or federal standards or criteria for barium in sediment in inland saline waters.

Objective/Criterion Reference:

Water Quality Control Plan for the Lahontan Region (as amended)

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

One station, Amargosa River at Upper Canyon, was sampled.

Temporal Representation:

One sediment sample was collected on March 15, 2005.

Environmental Conditions:

QAPP Information:

The data meet the quality assurance requirements of the SWAMP QAPP.

QAPP Information Reference(s):


DECISION ID	72634	Region 6
Amargosa River (Tecopa to Upper Canyon)

Pollutant:	Bicarbonate
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2016)
Revision Status	Original
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Staff Conclusion:	Regional Board conclusion: This pollutant was considered for placement on the section 303(d) list in a previous assessment cycle. No new information was reviewed for this current assessment cycle. Therefore, the previous conclusion remains unchanged, and is as follows: 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, consisting of two samples, is available in the administrative record to assess this pollutant. There are no applicable water quality standards or criteria for bicarbonate in inland saline waters. 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 satisfy the data quality requirements of section 6.1.4 of the Policy. 2. The data used do not satisfy the data quantity requirements of section 6.1.5 of the Policy. 3. There are no applicable water quality standards or criteria and the data cannot be assessed using 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 Staff Decision Recommendation:	This region was not assessed this cycle. All decisions have been carried over from the previous cycle and remain the same.

Line of Evidence (LOE) for Decision ID 72634, Bicarbonate	Region 6
Amargosa River (Tecopa to Upper Canyon)

LOE ID:

25183

Pollutant:

Bicarbonate

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Inland Saline Water Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

The U.S. Geological Survey sampled this station on March 17, 2004 and March 15, 2005 under the Region 6 SWAMP program. Two samples had bicarbonate concentrations of 694 and 610 mg/L.

Data Reference:

2007. SWAMP Data for the Amargosa Hydrologic Unit

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

There are no state or federal saltwater aquatic life standards or criteria for bicarbonate in inland saline waters.

Objective/Criterion Reference:

Water Quality Control Plan for the Lahontan Region (as amended)

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

One station, Amargosa River at Upper Canyon, was sampled.

Temporal Representation:

Two samples were taken on March 17, 2004 and March 15, 2005.

Environmental Conditions:

QAPP Information:

The data meet the quality assurance requirements of the SWAMP QAPP.

QAPP Information Reference(s):


DECISION ID	73411	Region 6
Amargosa River (Tecopa to Upper Canyon)

Pollutant:	Bismuth
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2016)
Revision Status	Original
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Staff Conclusion:	Regional Board conclusion: This pollutant was considered for placement on the setion 303(d) list in aprevious assessment cycle. No new information was reviewed for this current assessment cycle. Therefore the previous conclusion remains unchanged, and is as follows: 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, consisting of a single sediment sample, is available in the administrative record to assess this pollutant. There are no applicable water quality standards or criteria for bismuth in sediment of inland saline waters. 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 satisfy the data quality requirements of section 6.1.4 of the Policy. 2. The data used do not satisfy the data quantity requirements of section 6.1.5 of the Policy. 3. There are no applicable water quality standards or criteria and the single sample cannot be assessed using 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 Staff Decision Recommendation:	This region was not assessed this cycle. All decisions have been carried over from the previous cycle and remain the same.

Line of Evidence (LOE) for Decision ID 73411, Bismuth	Region 6
Amargosa River (Tecopa to Upper Canyon)

LOE ID:

24858

Pollutant:

Bismuth

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

None

Beneficial Use:

Inland Saline Water Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Chemical monitoring of sediments

Data Used to Assess Water Quality:

Data Reference:

2007. SWAMP Data for the Amargosa Hydrologic Unit

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

There are no state or federal standards or criteria for bismuth in sediment in inland saline waters.

Objective/Criterion Reference:

Water Quality Control Plan for the Lahontan Region (as amended)

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

One station, Amargosa River at Upper Canyon, was sampled.

Temporal Representation:

One sediment sample was collected on March 15, 2005.

Environmental Conditions:

QAPP Information:

The data meet the quality assurance requirements of the SWAMP QAPP.

QAPP Information Reference(s):


DECISION ID	73760	Region 6
Amargosa River (Tecopa to Upper Canyon)

Pollutant:	Boron
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2016)
Revision Status	Original
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Staff Conclusion:	Regional Board conclusion: This pollutant was considered for placement on the section 303(d) list in a previous assessment cycle. No new information was reviewed for this current assessment cycle. Therefore, the previous conclusion remains unchanged, and is as follows: 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. There are no applicable water quality standards or criteria.. 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 satisfy the data quality requirements of section 6.1.4 of the Policy. 2. The single sample does not satisfy the data quantity requirements of section 6.1.5 of the Policy. 3. There are no applicable water quality standards or criteria and the data cannot be assessed using 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 Staff Decision Recommendation:	This region was not assessed this cycle. All decisions have been carried over from the previous cycle and remain the same.

Line of Evidence (LOE) for Decision ID 73760, Boron	Region 6
Amargosa River (Tecopa to Upper Canyon)

LOE ID:

25221

Pollutant:

Boron

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Inland Saline Water Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

The U.S. Geological Survey sampled this station on March 17, 2004 and March 15, 2005 under the Region 6 SWAMP program. Two samples had dissolved boron concentrations of 9470 and 7910 ug/L.

Data Reference:

2007. SWAMP Data for the Amargosa Hydrologic Unit

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

There are no applicable state or federal saltwater aquatic life standards or criteria for boron in inland saline waters.

Objective/Criterion Reference:

Water Quality Control Plan for the Lahontan Region (as amended)

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

One station, Amargosa River at Upper Canyon, was sampled.

Temporal Representation:

Two samples were collected on March 17, 2004 and March 15, 2005.

Environmental Conditions:

The Amargosa River flows into California from Nevada and terminates in Death Valley. It is mostly ephemeral but there are perennial reaches. There is great seasonal and annual variability in flows. Most of the watershed is U.S. Bureau of Land Management or National Park land.

The Amargosa River is not designated for the Municipal and Domestic Supply (MUN) beneficial use. The MUN use designation was removed in Basin Plan amendments that took effect in 2002. The rationale for removing the use included naturally high salinity and levels of toxic substances such as arsenic, and fluctuating water quantity that would make the river an unreliable supply if treatment were feasible.

Boron in this watershed comes from natural sources and has accumulated to high concentrations through evapoconcentration in a closed basin over geologic time.

The perennial reaches of the Amargosa River and the associated riparian areas support a complex of rare, threatened or endangered fish and wildlife species. To Lahontan Water Board staff¿s knowledge, there are no salmonids in the river and there is no warm water fishery for human consumption.

QAPP Information:

The data meet the quality assurance requirements of the SWAMP QAPP.

QAPP Information Reference(s):


DECISION ID	73939	Region 6
Amargosa River (Tecopa to Upper Canyon)

Pollutant:	Cadmium
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2016)
Revision Status	Original
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Staff Conclusion:	Regional Board conclusion: This pollutant was considered for placement on the section 303(d) list in a previous assessment cycle. No new information was reviewed for this current assessment cycle. Therefore, the previous conclusion remains unchanged, and is as follows: 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. Three lines of evidence, consisting of one or two samples each, are available in the administrative record to assess this pollutant. There are no applicable saltwater aquatic life standards or criteria for cadmium in inland saline waters. The California Toxics Rule saltwater standards and a sediment criterion were not exceeded; both are based on toxicity to marine/estuarine organisms. 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 satisfy the data quality requirements of section 6.1.4 of the Policy. 2. The sediment data used do not satisfy the data quantity requirements of section 6.1.5 of the Policy. 3. There are no applicable water quality standards or criteria for inland saline waters. The CTR standards and the sediment criterion, based on marine/estuarine toxicity, were not exceeded and this does not exceed the allowable frequency in Table 3.1 of the Listing Policy. The single sediment sample does not meet the minimum sample number requirements 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 Staff Decision Recommendation:	This region was not assessed this cycle. All decisions have been carried over from the previous cycle and remain the same.

Line of Evidence (LOE) for Decision ID 73939, Cadmium	Region 6
Amargosa River (Tecopa to Upper Canyon)

LOE ID:

25008

Pollutant:

Cadmium

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Inland Saline Water Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

The U.S. Geological Survey sampled this station on March 17, 2004 and March 15, 2005 under the Region 6 SWAMP program. Two samples had dissolved cadmium concentrations of 0.1 and 0.8 ug/L.

Data Reference:

2007. SWAMP Data for the Amargosa Hydrologic Unit

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The California Toxics Rule's saltwater aquatic life standards for dissolved cadmium are an acute toxicity limit of 69 ug/L and a chronic toxicity limit of 36 ug/L.

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

One station, Amargosa River at Upper Canyon, was sampled.

Temporal Representation:

Two samples were collected on March 17, 2004 and March 15, 2005.

Environmental Conditions:

QAPP Information:

The data meet the quality assurance requirements of the SWAMP QAPP.

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 73939, Cadmium	Region 6
Amargosa River (Tecopa to Upper Canyon)

LOE ID:

24888

Pollutant:

Cadmium

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

None

Beneficial Use:

Inland Saline Water Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Chemical monitoring of sediments

Data Used to Assess Water Quality:

Data Reference:

2007. SWAMP Data for the Amargosa Hydrologic Unit

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

There are no state or federal standards or criteria for cadmium in sediment in inland saline waters. The Probable Effects Level for cadmium in marine and estuarine sediments is 4.21 ug/g dry weight; see Macdonald et al. (1996).

Objective/Criterion Reference:

Development and evaluation of sediment quality guidelines for Florida coastal waters. Ecotoxicology 5: 253-278

Water Quality Control Plan for the Lahontan Region (as amended)

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

One station, Amargosa River at Upper Canyon, was sampled.

Temporal Representation:

One sediment sample was collected on March 15, 2005.

Environmental Conditions:

QAPP Information:

The data meet the quality assurance requirements of the SWAMP QAPP.

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 73939, Cadmium	Region 6
Amargosa River (Tecopa to Upper Canyon)

LOE ID:

25009

Pollutant:

Cadmium

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Inland Saline Water Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

The U.S. Geological Survey sampled this station on March 17, 2004 and March 15, 2005 under the Region 6 SWAMP program. The concentrations of total cadmium in two samples were 0.11 and 0.11 ug/L.

Data Reference:

2007. SWAMP Data for the Amargosa Hydrologic Unit

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

There are no applicable state or federal saltwater aquatic life standards or criteria for total cadmium in in inland saline waters.

Objective/Criterion Reference:

Water Quality Control Plan for the Lahontan Region (as amended)

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

One station, Amargosa River at Upper Canyon, was sampled.

Temporal Representation:

Two samples were collected on March 17, 2004 and March 15, 2005.

Environmental Conditions:

QAPP Information:

The data meet the quality assurance requirements of the SWAMP QAPP.

QAPP Information Reference(s):


DECISION ID	73491	Region 6
Amargosa River (Tecopa to Upper Canyon)

Pollutant:	Caffeine
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2016)
Revision Status	Original
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Staff Conclusion:	Regional Board conclusion: This pollutant was considered for placement on the section 303(d) list in a previous assessment cycle. No new information was reviewed for this current assessment cycle. Therefore, the previous conclusion remains unchanged, and is as follows: 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. There are no applicable water quality standards or criteria. 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 satisfy the data quality requirements of section 6.1.4 of the Policy. 2. The single sample used does not satisfy the data quantity requirements of section 6.1.5 of the Policy. 3. There are no applicable water quality standards or criteria and the data cannot be assessed using 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 Staff Decision Recommendation:	This region was not assessed this cycle. All decisions have been carried over from the previous cycle and remain the same.

Line of Evidence (LOE) for Decision ID 73491, Caffeine	Region 6
Amargosa River (Tecopa to Upper Canyon)

LOE ID:

25584

Pollutant:

Caffeine

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Inland Saline Water Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

The U.S. Geological Survey sampled this station on March 15, 2005 under the Region 6 SWAMP program. The concentration of caffeine in one sample was 0.0143 ug/L..

Data Reference:

2007. SWAMP Data for the Amargosa Hydrologic Unit

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

There are no state or federal water quality standards or criteria for caffeine in inland saline waters.

Objective/Criterion Reference:

Water Quality Control Plan for the Lahontan Region (as amended)

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

One station, Amargosa River at Upper Canyon, was sampled.

Temporal Representation:

One sample was collected on March 15, 2005

Environmental Conditions:

QAPP Information:

The data meet the quality assurance requirements of the SWAMP QAPP.

QAPP Information Reference(s):


DECISION ID	74258	Region 6
Amargosa River (Tecopa to Upper Canyon)

Pollutant:	Calcium
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2016)
Revision Status	Original
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Staff Conclusion:	Regional Board conclusion: This pollutant was considered for placement on the section 303(d) list in a previous assessment cycle. No new information was reviewed for this current assessment cycle. Therefore, the previous conclusion remains unchanged, and is as follows: 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. Three lines of evidence, consisting of one or two samples each, are available in the administrative record to assess this pollutant. There are no applicable saltwater aquatic life standards or criteria for calcium in inland saline waters. 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 satisfy the data quality requirements of section 6.1.4 of the Policy. 2. The sediment data used do not satisfy the data quantity requirements of section 6.1.5 of the Policy. 3. There are no applicable water quality standards or criteria and the data cannot be assessed using 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 Staff Decision Recommendation:	This region was not assessed this cycle. All decisions have been carried over from the previous cycle and remain the same.

Line of Evidence (LOE) for Decision ID 74258, Calcium	Region 6
Amargosa River (Tecopa to Upper Canyon)

LOE ID:

25163

Pollutant:

Calcium

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Inland Saline Water Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

The U.S. Geological Survey sampled this station on March 17, 2004 and March 15, 2005 under the Region 6 SWAMP program. Two samples had dissolved calcium concentrations of 35.1 and 46.5 mg/L.

Data Reference:

2007. SWAMP Data for the Amargosa Hydrologic Unit

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

There are no state or federal saltwater aquatic life standards or criteria for dissolved calcium in inland saline waters.

Objective/Criterion Reference:

Water Quality Control Plan for the Lahontan Region (as amended)

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

One station, Amargosa River at Upper Canyon, was sampled.

Temporal Representation:

Two samples were taken on March 17, 2004 and March 15, 2005.

Environmental Conditions:

QAPP Information:

The data meet the quality assurance requirements of the SWAMP QAPP.

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 74258, Calcium	Region 6
Amargosa River (Tecopa to Upper Canyon)

LOE ID:

25165

Pollutant:

Calcium

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Inland Saline Water Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

The U.S. Geological Survey sampled this station on March 17, 2004 and March 15, 2005 under the Region 6 SWAMP program. Two samples had total calcium concentrations of 43.4 and 41.2 mg/L.

Data Reference:

2007. SWAMP Data for the Amargosa Hydrologic Unit

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

There are no state or federal saltwater aquatic life standards or criteria for total calcium in inland saline waters.

Objective/Criterion Reference:

Water Quality Control Plan for the Lahontan Region (as amended)

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

One station, Amargosa River at Upper Canyon, was sampled.

Temporal Representation:

Two samples were taken on March 17, 2004 and March 15, 2005.

Environmental Conditions:

QAPP Information:

The data meet the quality assurance requirements of the SWAMP QAPP.

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 74258, Calcium	Region 6
Amargosa River (Tecopa to Upper Canyon)

LOE ID:

24844

Pollutant:

Calcium

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

None

Beneficial Use:

Inland Saline Water Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Chemical monitoring of sediments

Data Used to Assess Water Quality:

Data Reference:

2007. SWAMP Data for the Amargosa Hydrologic Unit

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

There are no state or federal standards or criteria for calcium in sediment in inland saline waters.

Objective/Criterion Reference:

Water Quality Control Plan for the Lahontan Region (as amended)

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

One station, Amargosa River at Upper Canyon, was sampled.

Temporal Representation:

One sediment sample was collected on March 15, 2005.

Environmental Conditions:

QAPP Information:

The data meet the quality assurance requirements of the SWAMP QAPP.

QAPP Information Reference(s):


DECISION ID	73295	Region 6
Amargosa River (Tecopa to Upper Canyon)

Pollutant:	Carbon (inorganic)
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2016)
Revision Status	Original
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Staff Conclusion:	Regional Board conclusion: This pollutant was considered for placement on the section 303(d) list in a previous assessment cycle. No new information was reviewed for this current assessment cycle. Therefore, the previous conclusion remains unchanged, and is as follows: 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, consisting of a single sediment sample, is available in the administrative record to assess this pollutant. There are no applicable water quality standards or criteria for inorganic carbon in the sediment of inland saline waters. 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 satisfy the data quality requirements of section 6.1.4 of the Policy. 2. The data used do not satisfy the data quantity requirements of section 6.1.5 of the Policy. 3. There are no applicable water quality standards or criteria and the single sample cannot be assessed using 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 Staff Decision Recommendation:	This region was not assessed this cycle. All decisions have been carried over from the previous cycle and remain the same.

Line of Evidence (LOE) for Decision ID 73295, Carbon (inorganic)	Region 6
Amargosa River (Tecopa to Upper Canyon)

LOE ID:

24850

Pollutant:

Carbon (inorganic)

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

None

Beneficial Use:

Inland Saline Water Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Chemical monitoring of sediments

Data Used to Assess Water Quality:

Data Reference:

2007. SWAMP Data for the Amargosa Hydrologic Unit

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

There are no state or federal standards or criteria for carbon in sediment in inland saline waters.

Objective/Criterion Reference:

Water Quality Control Plan for the Lahontan Region (as amended)

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

One station, Amargosa River at Upper Canyon, was sampled.

Temporal Representation:

One sediment sample was collected on March 15, 2005.

Environmental Conditions:

QAPP Information:

The data meet the quality assurance requirements of the SWAMP QAPP.

QAPP Information Reference(s):


DECISION ID	72879	Region 6
Amargosa River (Tecopa to Upper Canyon)

Pollutant:	Carbon (organic + inorganic)
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2016)
Revision Status	Original
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Staff Conclusion:	Regional Board conclusion: This pollutant was considered for placement on the section 303(d) list in a previous assessment cycle. No new information was reviewed for this current assessment cycle. Therefore, the previous conclusion remains unchanged, and is as follows: 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, consisting of a single sediment sample, is available in the administrative record to assess this pollutant. There are no applicable water quality standards or criteria for organic plus inorganic carbon in the sediment of inland saline waters. 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 satisfy the data quality requirements of section 6.1.4 of the Policy. 2. The data used do not satisfy the data quantity requirements of section 6.1.5 of the Policy. 3. There are no applicable water quality standards or criteria and the single sample cannot be assessed using 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 Staff Decision Recommendation:	This region was not assessed this cycle. All decisions have been carried over from the previous cycle and remain the same.

Line of Evidence (LOE) for Decision ID 72879, Carbon (organic + inorganic)	Region 6
Amargosa River (Tecopa to Upper Canyon)

LOE ID:

24849

Pollutant:

Carbon (organic + inorganic)

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

None

Beneficial Use:

Inland Saline Water Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Chemical monitoring of sediments

Data Used to Assess Water Quality:

Data Reference:

2007. SWAMP Data for the Amargosa Hydrologic Unit

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

There are no state or federal standards or criteria for carbon in sediment in inland saline waters.

Objective/Criterion Reference:

Water Quality Control Plan for the Lahontan Region (as amended)

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

One station, Amargosa River at Upper Canyon, was sampled.

Temporal Representation:

One sediment sample was collected on March 15, 2005.

Environmental Conditions:

QAPP Information:

The data meet the quality assurance requirements of the SWAMP QAPP.

QAPP Information Reference(s):


DECISION ID	72930	Region 6
Amargosa River (Tecopa to Upper Canyon)

Pollutant:	Carbon (organic)
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2016)
Revision Status	Original
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Staff Conclusion:	Regional Board conclusion: This pollutant was considered for placement on the section 303(d) list in a previous assessment cycle. No new information was reviewed for this current assessment cycle. Therefore, the previous conclusion remains unchanged, and is as follows: 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, consisting of a single sediment sample, is available in the administrative record to assess this pollutant. There are no applicable water quality standards or criteria for organic carbon in the sediment of inland saline waters. 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 satisfy the data quality requirements of section 6.1.4 of the Policy. 2. The data used do not satisfy the data quantity requirements of section 6.1.5 of the Policy. 3. There are no applicable water quality standards or criteria and the single sample cannot be assessed using 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 Staff Decision Recommendation:	This region was not assessed this cycle. All decisions have been carried over from the previous cycle and remain the same.

Line of Evidence (LOE) for Decision ID 72930, Carbon (organic)	Region 6
Amargosa River (Tecopa to Upper Canyon)

LOE ID:

25185

Pollutant:

Carbon (organic)

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

None

Beneficial Use:

Inland Saline Water Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Chemical monitoring of sediments

Data Used to Assess Water Quality:

Data Reference:

2007. SWAMP Data for the Amargosa Hydrologic Unit

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

There are no state or federal standards or criteria for organic carbon in sediment in inland saline waters.

Objective/Criterion Reference:

Water Quality Control Plan for the Lahontan Region (as amended)

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

One station, Amargosa River at Upper Canyon, was sampled.

Temporal Representation:

One sediment sample was collected on March 15, 2005.

Environmental Conditions:

QAPP Information:

The data meet the quality assurance requirements of the SWAMP QAPP.

QAPP Information Reference(s):


DECISION ID	72688	Region 6
Amargosa River (Tecopa to Upper Canyon)

Pollutant:	Carbonate
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2016)
Revision Status	Original
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Staff Conclusion:	Regional Board conclusion: This pollutant was considered for placement on the section 303(d) list in a previous assessment cycle. No new information was reviewed for this current assessment cycle. Therefore, the previous conclusion remains unchanged, and is as follows: 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, consisting of two samples, is available in the administrative record to assess this pollutant. There are no applicable water quality standards or criteria for bicarbonate in inland saline waters. 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 satisfy the data quality requirements of section 6.1.4 of the Policy. 2. The data used do not satisfy the data quantity requirements of section 6.1.5 of the Policy. 3. There are no applicable water quality standards or criteria and the data cannot be assessed using 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 Staff Decision Recommendation:	This region was not assessed this cycle. All decisions have been carried over from the previous cycle and remain the same.

Line of Evidence (LOE) for Decision ID 72688, Carbonate	Region 6
Amargosa River (Tecopa to Upper Canyon)

LOE ID:

25184

Pollutant:

Carbonate

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Inland Saline Water Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

The U.S. Geological Survey sampled this station on March 17, 2004 and March 15, 2005 under the Region 6 SWAMP program. Two samples had carbonate concentrations of 24 and 48 mg/L.

Data Reference:

2007. SWAMP Data for the Amargosa Hydrologic Unit

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

There are no state or federal saltwater aquatic life standards or criteria for carbonate in inland saline waters.

Objective/Criterion Reference:

Water Quality Control Plan for the Lahontan Region (as amended)

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

One station, Amargosa River at Upper Canyon, was sampled.

Temporal Representation:

Two samples were taken on March 17, 2004 and March 15, 2005.

Environmental Conditions:

QAPP Information:

The data meet the quality assurance requirements of the SWAMP QAPP.

QAPP Information Reference(s):


DECISION ID	73544	Region 6
Amargosa River (Tecopa to Upper Canyon)

Pollutant:	Cerium
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2016)
Revision Status	Original
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Staff Conclusion:	Regional Board conclusion: This pollutant was considered for palcement on the section 303(d) list in a previous assessment cycle. No new information was reviewed for this current assessment cycle. Therefore, the previous conclusion remains unchanged, and is as follows: 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. There are no applicable water quality standards or criteria. 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 satisfy the data quality requirements of section 6.1.4 of the Policy. 2. The single sample used does not satisfy the data quantity requirements of section 6.1.5 of the Policy. 3. There are no applicable water quality standards or criteria and the data cannot be assessed using 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 Staff Decision Recommendation:	This region was not assessed this cycle. All decisions have been carried over from the previous cycle and remain the same.

Line of Evidence (LOE) for Decision ID 73544, Cerium	Region 6
Amargosa River (Tecopa to Upper Canyon)

LOE ID:

24859

Pollutant:

Cerium

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

None

Beneficial Use:

Inland Saline Water Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Chemical monitoring of sediments

Data Used to Assess Water Quality:

Data Reference:

2007. SWAMP Data for the Amargosa Hydrologic Unit

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

There are no state or federal standards or criteria for cerium in sediment in inland saline waters.

Objective/Criterion Reference:

Water Quality Control Plan for the Lahontan Region (as amended)

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

One station, Amargosa River at Upper Canyon, was sampled.

Temporal Representation:

One sediment sample was collected on March 15, 2005.

Environmental Conditions:

QAPP Information:

The data meet the quality assurance requirements of the SWAMP QAPP.

QAPP Information Reference(s):


DECISION ID	72797	Region 6
Amargosa River (Tecopa to Upper Canyon)

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)(2016)
Revision Status	Original
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Staff Conclusion:	Regional Board conclusion: This pollutant was considered for placement on the section 303(d) list in a previous assessment cycle. No new information was reviewed for this current assessment cycle. Therefore, the previous conclusion remains unchanged, and is as follows: 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, consisting of two samples, is available in the administrative record to assess this pollutant. There are no applicable water quality standards or criteria for chloride in inland saline waters. 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 satisfy the data quality requirements of section 6.1.4 of the Policy. 2. The data used do not satisfy the data quantity requirements of section 6.1.5 of the Policy. 3. There are no applicable water quality standards or criteria and the data cannot be assessed using 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 Staff Decision Recommendation:	This region was not assessed this cycle. All decisions have been carried over from the previous cycle and remain the same.

Line of Evidence (LOE) for Decision ID 72797, Chloride	Region 6
Amargosa River (Tecopa to Upper Canyon)

LOE ID:

25170

Pollutant:

Chloride

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Inland Saline Water Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

The U.S. Geological Survey sampled this station on March 17, 2004 and March 15, 2005 under the Region 6 SWAMP program. Two samples had dissolved chloride concentrations of 422 and 295 mg/L.

Data Reference:

2007. SWAMP Data for the Amargosa Hydrologic Unit

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

There are no state or federal saltwater aquatic life standards or criteria for dissolved chloride in inland saline waters.

Objective/Criterion Reference:

Water Quality Control Plan for the Lahontan Region (as amended)

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

One station, Amargosa River at Upper Canyon, was sampled.

Temporal Representation:

Two samples were taken on March 17, 2004 and March 15, 2005.

Environmental Conditions:

QAPP Information:

The data meet the quality assurance requirements of the SWAMP QAPP.

QAPP Information Reference(s):


DECISION ID	72959	Region 6
Amargosa River (Tecopa to Upper Canyon)

Pollutant:	Chromium (total)
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2016)
Revision Status	Original
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Staff Conclusion:	Regional Board conclusion: This pollutant was considered for placement on the section 303(d) list in a previous assessment cycle. No new information was reviewed for this current assessment cycle. Therefore, the previous conclusion remains unchanged, and is as follows: 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. Thred lines of evidence, consisting of one or two samples each, are available in the administrative record to assess this pollutant. There are no applicable saltwater aquatic life standards or criteria for chromium in inland saline waters. The California Toxics Rule (CTR) standard and a sediment criterion were not exceeded. These standards are based on toxicity to marine/estuarine organisms. 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 satisfy the data quality requirements of section 6.1.4 of the Policy. 2. The sediment data used do not satisfy the data quantity requirements of section 6.1.5 of the Policy. 3. There are no applicable water quality standards or criteria for inland saline waters. The CTR saltwater standards and sediment criterion were not exceeded and this does not exceed the allowable frequency in Table 3.1 of the listing policy. However, the single sediment sample did not meet the minimum sample number requirements 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 Staff Decision Recommendation:	This region was not assessed this cycle. All decisions have been carried over from the previous cycle and remain the same.

Line of Evidence (LOE) for Decision ID 72959, Chromium (total)	Region 6
Amargosa River (Tecopa to Upper Canyon)

LOE ID:

25011

Pollutant:

Chromium (total)

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Inland Saline Water Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

The U.S. Geological Survey sampled this station on March 17, 2004 and March 15, 2005 under the Region 6 SWAMP program. One of two samples for dissolved chromium was below the detection level and the other was an estimated value.

Data Reference:

2007. SWAMP Data for the Amargosa Hydrologic Unit

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The California Toxics Rule's saltwater aquatic life standards for dissolved chromium are an acute toxicity limit of 1100 ug/L and a chronic toxicity limit of 50 ug/L.

Objective/Criterion Reference:

Water Quality Control Plan for the Lahontan Region (as amended)

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

One station, Amargosa River at Upper Canyon, was sampled.

Temporal Representation:

Two samples were collected on March 17, 2004 and March 15, 2005.

Environmental Conditions:

QAPP Information:

The data meet the quality assurance requirements of the SWAMP QAPP.

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 72959, Chromium (total)	Region 6
Amargosa River (Tecopa to Upper Canyon)

LOE ID:

24885

Pollutant:

Chromium (total)

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

None

Beneficial Use:

Inland Saline Water Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Chemical monitoring of sediments

Data Used to Assess Water Quality:

Data Reference:

2007. SWAMP Data for the Amargosa Hydrologic Unit

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

There are no state or federal standards or criteria for chromium in sediment in inland saline waters. The Effects Range-Median for chromium in marine and estuarine sediments is 370 ug/g dry weight; see Long et al. (1995).

Objective/Criterion Reference:

Incidence of adverse biological effects within ranges of chemical concentrations in marine and estuary sediments. Environmental Management. 19, (1): 81-97

Water Quality Control Plan for the Lahontan Region (as amended)

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

One station, Amargosa River at Upper Canyon, was sampled.

Temporal Representation:

One sediment sample was collected on March 15, 2005.

Environmental Conditions:

QAPP Information:

The data meet the quality assurance requirements of the SWAMP QAPP.

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 72959, Chromium (total)	Region 6
Amargosa River (Tecopa to Upper Canyon)

LOE ID:

25010

Pollutant:

Chromium (total)

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Inland Saline Water Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

The U.S. Geological Survey sampled this station on March 17, 2004 and March 15, 2005 under the Region 6 SWAMP program. One of two samples for total chromium was below the detection level and the concentration in the other was 0.0 ug/L.

Data Reference:

2007. SWAMP Data for the Amargosa Hydrologic Unit

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

There are no applicable state or federal saltwater aquatic life standards or criteria for total chromium in inland saline waters.

Objective/Criterion Reference:

Water Quality Control Plan for the Lahontan Region (as amended)

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

One station, Amargosa River at Upper Canyon, was sampled.

Temporal Representation:

Two samples were collected on March 17, 2004 and March 15, 2005.

Environmental Conditions:

QAPP Information:

The data meet the quality assurance requirements of the SWAMP QAPP.

QAPP Information Reference(s):


DECISION ID	75179	Region 6
Amargosa River (Tecopa to Upper Canyon)

Pollutant:	Copper
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2016)
Revision Status	Original
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Staff Conclusion:	Regional Board conclusion: This pollutant was considered for placement on the section 303(d) list in a previous assessment cycle. No new information was reviewed for this current assessment cycle. Therefore, the previous conclusion remains unchanged, and is as follows: 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. Three lines of evidence, for total and dissolved copper in water, and copper in sediment, are available in the administrative record to assess this pollutant. None of the samples exceeds the California Toxics Rule standard or the marine/estuarine sediment criterion.. 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 satisfy the data quality requirements of section 6.1.4 of the Policy. 2. The data used do not satisfy the data quantity requirements of section 6.1.5 of the Policy. Only one water sample per year was collected. 3. Neither of two water samples nor the single sediment sample exceeded the applicable standards or criterion 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 Staff Decision Recommendation:	This region was not assessed this cycle. All decisions have been carried over from the previous cycle and remain the same.

Line of Evidence (LOE) for Decision ID 75179, Copper	Region 6
Amargosa River (Tecopa to Upper Canyon)

LOE ID:

25015

Pollutant:

Copper

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Inland Saline Water Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

The U.S. Geological Survey sampled this station on March 17, 2004 and March 15, 2005 under the Region 6 SWAMP program. Two samples dissolved total copper concentrations of 3 and 2.8 ug/L.

Data Reference:

2007. SWAMP Data for the Amargosa Hydrologic Unit

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The California Toxics Rule's saltwater aquatic life standards
for dissolved copper include an acute toxicity limit of 4.8 ug/L and a chronic toxicity limit of 3.1 ug/L.

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

One station, Amargosa River at Upper Canyon, was sampled.

Temporal Representation:

Two samples were collected on March 17, 2004 and March 15, 2005.

Environmental Conditions:

QAPP Information:

The data meet the quality assurance requirements of the SWAMP QAPP.

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 75179, Copper	Region 6
Amargosa River (Tecopa to Upper Canyon)

LOE ID:

25014

Pollutant:

Copper

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Inland Saline Water Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

The U.S. Geological Survey sampled this station on March 17, 2004 and March 15, 2005 under the Region 6 SWAMP program. Two samples had total copper concentrations of 6 and 13.2 ug/L.

Data Reference:

2007. SWAMP Data for the Amargosa Hydrologic Unit

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

There are no applicable state or federal saltwater aquatic life standards or criteria for total copper for inland saline waters.

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

One station, Amargosa River at Upper Canyon, was sampled.

Temporal Representation:

Two samples were collected on March 17, 2004 and March 15, 2005.

Environmental Conditions:

QAPP Information:

The data meet the quality assurance requirements of the SWAMP QAPP.

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 75179, Copper	Region 6
Amargosa River (Tecopa to Upper Canyon)

LOE ID:

24886

Pollutant:

Copper

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

None

Beneficial Use:

Inland Saline Water Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Chemical monitoring of sediments

Data Used to Assess Water Quality:

Data Reference:

2007. SWAMP Data for the Amargosa Hydrologic Unit

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

There are no state or federal standards or criteria for copper in sediment in inland saline waters. The Effects Range-Median for copper in marine and estuarine sediments is 270 ug/g dry weight; see Long et al. (1995).

Objective/Criterion Reference:

Incidence of adverse biological effects within ranges of chemical concentrations in marine and estuary sediments. Environmental Management. 19, (1): 81-97

Water Quality Control Plan for the Lahontan Region (as amended)

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

One station, Amargosa River at Upper Canyon, was sampled.

Temporal Representation:

One sediment sample was collected on March 15, 2005.

Environmental Conditions:

QAPP Information:

The data meet the quality assurance requirements of the SWAMP QAPP.

QAPP Information Reference(s):


DECISION ID	75443	Region 6
Amargosa River (Tecopa to Upper Canyon)

Pollutant:	Deuterium/Protium ratio
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2016)
Revision Status	Original
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Staff Conclusion:	Regional Board conclusion: This pollutant was considered for placement on the section 303(d) list in a previous assessment cycle. No new information was reviewed for this current assessment cycle. Therefore, the previous conclusion remains unchanged, and is as follows: 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. There are no applicable water quality standards or criteria. 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 satisfy the data quality requirements of section 6.1.4 of the Policy. 2. The data used do not satisfy the data quantity requirements of section 6.1.5 of the Policy. 3. There are no applicable water quality standards or criteria and the data cannot be assessed using 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 Staff Decision Recommendation:	This region was not assessed this cycle. All decisions have been carried over from the previous cycle and remain the same.

Line of Evidence (LOE) for Decision ID 75443, Deuterium/Protium ratio	Region 6
Amargosa River (Tecopa to Upper Canyon)

LOE ID:

27057

Pollutant:

Deuterium/Protium ratio

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Inland Saline Water Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

The U.S. Geological Survey sampled this station on March 17, 2004 and March 15, 2005 under the Region 6 SWAMP program. Two samples had deuterium/protium ratios of -91.7 and -91.9 per mL.

Data Reference:

2007. SWAMP Data for the Amargosa Hydrologic Unit

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

There are no state or federal saltwater aquatic life standards or criteria for deuterium/protium ratio in inland saline waters.

Objective/Criterion Reference:

Water Quality Control Plan for the Lahontan Region (as amended)

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

One station, Amargosa River at Upper Canyon, was sampled.

Temporal Representation:

Two samples were collected on March 17, 2004 and March 15, 2005.

Environmental Conditions:

QAPP Information:

The data meet the quality assurance requirements of the SWAMP QAPP.

QAPP Information Reference(s):


DECISION ID	73273	Region 6
Amargosa River (Tecopa to Upper Canyon)

Pollutant:	Dissolved oxygen saturation
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2016)
Revision Status	Original
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Staff Conclusion:	Regional Board conclusion: This pollutant was considered for placement on the section 303(d) list in a previous assessment cycle. No new information was reviewed for this current assessment cycle. Therefore, the previous conclusion remains unchanged, and is as follows: 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. Neither of the two of the samples exceeds 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 satisfy the data quality requirements of section 6.1.4 of the Policy. 2. The data used do satisfy the data quantity requirements of section 6.1.5 of the Policy. 3. Neither of two samples exceeded the water quality objective and this does not exceed the allowable frequency listed in Table 3.2 of the Listing Policy. However, the minimum sample number requirements of Table 3.2 were not met. 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 Staff Decision Recommendation:	This region was not assessed this cycle. All decisions have been carried over from the previous cycle and remain the same.

Line of Evidence (LOE) for Decision ID 73273, Dissolved oxygen saturation	Region 6
Amargosa River (Tecopa to Upper Canyon)

LOE ID:

25157

Pollutant:

Dissolved oxygen saturation

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

The U.S. Geological Survey sampled this station on March 17, 2004 and March 15, 2005 under the Region 6 SWAMP program. Two samples had percent saturation values of 121 and 118 percent dissolved oxygen.

Data Reference:

2007. SWAMP Data for the Amargosa Hydrologic Unit

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The Lahontan Basin Plan's regionwide narrative objective for dissolved oxygen provides that percent saturation shall not be depressed more than 10 percent nor shall the minimum dissolved oxygen concentration be less than 80 percent of saturation.

Objective/Criterion Reference:

Water Quality Control Plan for the Lahontan Region (as amended)

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

One station, Amargosa River at Upper Canyon, was sampled.

Temporal Representation:

Two samples were collected on March 17, 2004 and March 15, 2005.

Environmental Conditions:

QAPP Information:

The data meet the quality assurance requirements of the SWAMP QAPP.

QAPP Information Reference(s):


DECISION ID	73796	Region 6
Amargosa River (Tecopa to Upper Canyon)

Pollutant:	Europium
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2016)
Revision Status	Original
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Staff Conclusion:	Regional Board conclusion: This pollutant was considered for placement on the section 303(d) list in a previous assessment cycle. No new information was reviewed for this current assessment cycle. Therefore, the previous conclusion remains unchanged, and is as follows: 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. There are no applicable water quality standards or criteria. 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 satisfy the data quality requirements of section 6.1.4 of the Policy. 2. The single sample used does not satisfy the data quantity requirements of section 6.1.5 of the Policy. 3. There are no applicable water quality standards or criteria and the data cannot be assessed using 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 Staff Decision Recommendation:	This region was not assessed this cycle. All decisions have been carried over from the previous cycle and remain the same.

Line of Evidence (LOE) for Decision ID 73796, Europium	Region 6
Amargosa River (Tecopa to Upper Canyon)

LOE ID:

24861

Pollutant:

Europium

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

None

Beneficial Use:

Inland Saline Water Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Chemical monitoring of sediments

Data Used to Assess Water Quality:

Data Reference:

2007. SWAMP Data for the Amargosa Hydrologic Unit

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

There are no state or federal standards or criteria for europium in sediment in inland saline waters.

Objective/Criterion Reference:

Water Quality Control Plan for the Lahontan Region (as amended)

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

One station, Amargosa River at Upper Canyon, was sampled.

Temporal Representation:

One sediment sample was collected on March 15, 2005.

Environmental Conditions:

QAPP Information:

The data meet the quality assurance requirements of the SWAMP QAPP.

QAPP Information Reference(s):


DECISION ID	74018	Region 6
Amargosa River (Tecopa to Upper Canyon)

Pollutant:	Fluoride
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2016)
Revision Status	Original
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Staff Conclusion:	Regional Board conclusion: This pollutant was considered for placement on the section 303(d) list in a previous assessment cycle. No new information was reviewed for this current assessment cycle. Therefore, the previous conclusion remains unchanged, and is as follows: 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. There are no applicable water quality standards or criteria.. 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 satisfy the data quality requirements of section 6.1.4 of the Policy. 2. The data used do not satisfy the data quantity requirements of section 6.1.5 of the Policy. 3. There are no applicable water quality standards or criteria and the data cannot be assessed using 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 Staff Decision Recommendation:	This region was not assessed this cycle. All decisions have been carried over from the previous cycle and remain the same.

Line of Evidence (LOE) for Decision ID 74018, Fluoride	Region 6
Amargosa River (Tecopa to Upper Canyon)

LOE ID:

25171

Pollutant:

Fluoride

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Inland Saline Water Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

The U.S. Geological Survey sampled this station on March 17, 2004 and March 15, 2005 under the Region 6 SWAMP program. Two samples had dissolved fluoride concentrations of 4.4 and 3.7 mg/L.

Data Reference:

2007. SWAMP Data for the Amargosa Hydrologic Unit

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

There are no state or federal saltwater aquatic life standards or criteria for dissolved fluoride in inland saline waters.

Objective/Criterion Reference:

Water Quality Control Plan for the Lahontan Region (as amended)

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

One station, Amargosa River at Upper Canyon, was sampled.

Temporal Representation:

Two samples were taken on March 17, 2004 and March 15, 2005.

Environmental Conditions:

QAPP Information:

The data meet the quality assurance requirements of the SWAMP QAPP.

QAPP Information Reference(s):


DECISION ID	73154	Region 6
Amargosa River (Tecopa to Upper Canyon)

Pollutant:	Gallium
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2016)
Revision Status	Original
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Staff Conclusion:	Regional Board conclusioion: This pollutant was condisered for placement on the section 303(d) list in a previous assessment cycle. No new information was reviewed for his current assessment cycle. Therefore, the previous conclusion remains unchanged, and is as follows: 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, consisting of a single sediment sample, is available in the administrative record to assess this pollutant. There are no applicable water quality standards or criteria for gallium in sediment of inland saline waters. 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 satisfy the data quality requirements of section 6.1.4 of the Policy. 2. The data used do not satisfy the data quantity requirements of section 6.1.5 of the Policy. 3. There are no applicable water quality standards or criteria and the single sample cannot be assessed using 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 Staff Decision Recommendation:	This region was not assessed this cycle. All decisions have been carried over from the previous cycle and remain the same.

Line of Evidence (LOE) for Decision ID 73154, Gallium	Region 6
Amargosa River (Tecopa to Upper Canyon)

LOE ID:

24862

Pollutant:

Gallium

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

None

Beneficial Use:

Inland Saline Water Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Chemical monitoring of sediments

Data Used to Assess Water Quality:

Data Reference:

2007. SWAMP Data for the Amargosa Hydrologic Unit

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

There are no state or federal standards or criteria for gallium in sediment in inland saline waters.

Objective/Criterion Reference:

Water Quality Control Plan for the Lahontan Region (as amended)

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

One station, Amargosa River at Upper Canyon, was sampled.

Temporal Representation:

One sediment sample was collected on March 15, 2005.

Environmental Conditions:

QAPP Information:

The data meet the quality assurance requirements of the SWAMP QAPP.

QAPP Information Reference(s):


DECISION ID	72937	Region 6
Amargosa River (Tecopa to Upper Canyon)

Pollutant:	Gold
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2016)
Revision Status	Original
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Staff Conclusion:	Regional Board conclusion: This pollutant was considered for placement on the section 303(d) list in a previous assessment cycle. No new information was reviewed for this current assessment cycle. Therefore, the previous conclusion remains unchanged, and is as follows: 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, consisting of a single sediment sample, is available in the administrative record to assess this pollutant. There are no applicable water quality standards or criteria for gold in sediment of inland saline waters. 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 satisfy the data quality requirements of section 6.1.4 of the Policy. 2. The data used do not satisfy the data quantity requirements of section 6.1.5 of the Policy. 3. There are no applicable water quality standards or criteria and the single sample cannot be assessed using 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 Staff Decision Recommendation:	This region was not assessed this cycle. All decisions have been carried over from the previous cycle and remain the same.

Line of Evidence (LOE) for Decision ID 72937, Gold	Region 6
Amargosa River (Tecopa to Upper Canyon)

LOE ID:

24863

Pollutant:

Gold

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

None

Beneficial Use:

Inland Saline Water Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Chemical monitoring of sediments

Data Used to Assess Water Quality:

Data Reference:

2007. SWAMP Data for the Amargosa Hydrologic Unit

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

There are no state or federal standards or criteria for gold in sediment in inland saline waters.

Objective/Criterion Reference:

Water Quality Control Plan for the Lahontan Region (as amended)

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

One station, Amargosa River at Upper Canyon, was sampled.

Temporal Representation:

One sediment sample was collected on March 15, 2005.

Environmental Conditions:

QAPP Information:

The data meet the quality assurance requirements of the SWAMP QAPP.

QAPP Information Reference(s):


DECISION ID	75492	Region 6
Amargosa River (Tecopa to Upper Canyon)

Pollutant:	Gross Alpha Radioactivity
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2016)
Revision Status	Original
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Staff Conclusion:	Regional Board conclusion: This pollutant was considered for placement on the section 303(d) list in a previous assessment cycle. No new information was reviewed for this current assessment cycle. Therefore, the previous conclusion remains unchanged, and is as follows: 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 biological data are available to assess whether either of the samples exceeds 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 satisfy the data quality requirements of section 6.1.4 of the Policy. 2. The data used do not satisfy the data quantity requirements of section 6.1.5 of the Policy. (Only one sample per year was taken.) 3. No biological data are available for assessment of compliance with the objective and the two samples cannot be assessed using 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 Staff Decision Recommendation:	This region was not assessed this cycle. All decisions have been carried over from the previous cycle and remain the same.

Line of Evidence (LOE) for Decision ID 75492, Gross Alpha Radioactivity	Region 6
Amargosa River (Tecopa to Upper Canyon)

LOE ID:

27058

Pollutant:

Gross Alpha Radioactivity

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Inland Saline Water Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

The U.S. Geological Survey sampled this station on March 17, 2004 and March 15, 2005 under the Region 6 SWAMP program. Two samples had gross alpha radioactivity levels of 11 and 16.4 pCi/L. No biological data are available for assessment of compliance with the narrative water quality objective.

Data Reference:

2007. SWAMP Data for the Amargosa Hydrologic Unit

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

There are no specific state or federal saltwater aquatic life standards or criteria for gross alpha radioactivity in inland saline waters. The Lahontan Basin Plan's narrative water quality objective for radioactivity provides that: "Radionuclides shall not be present in concentrations which are deleterious to human, plant, animal, or aquatic life nor which result in the accumulation of radionuclides in the food web to an extent which presents a hazard to human, plant, animal or aquatic life." The objective also incorporates California Maximum Contaminant Levels (MUN) for radioactivity for waters designated for the MUN use. The MCLs do not apply to the Amargosa River.

Objective/Criterion Reference:

Water Quality Control Plan for the Lahontan Region (as amended)

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

One station, Amargosa River at Upper Canyon, was sampled.

Temporal Representation:

Two samples were collected on March 17, 2004 and March 15, 2005.

Environmental Conditions:

QAPP Information:

The data meet the quality assurance requirements of the SWAMP QAPP.

QAPP Information Reference(s):


DECISION ID	68324	Region 6
Amargosa River (Tecopa to Upper Canyon)

Pollutant:	Gross Beta Radioactivity
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2016)
Revision Status	Original
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Staff Conclusion:	Regional Board conclusion: This pollutant was considered for placement on the section 303(d) list in a previous assessment cycle. No new information was reviewed for this current assessment cycle. Therefore, the previous conclusion remains unchanged, and is as follows: 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 biological data are available for assessment whether either of the two samples exceeds 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 satisfy the data quality requirements of section 6.1.4 of the Policy. 2. The data used do not satisfy the data quantity requirements of section 6.1.5 of the Policy. 3. There are no biological data available for assessment of compliance with the narrative water quality objective and the data cannot be assessed using 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 Staff Decision Recommendation:	This region was not assessed this cycle. All decisions have been carried over from the previous cycle and remain the same.

Line of Evidence (LOE) for Decision ID 68324, Gross Beta Radioactivity	Region 6
Amargosa River (Tecopa to Upper Canyon)

LOE ID:

27141

Pollutant:

Gross Beta Radioactivity

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Inland Saline Water Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

The U.S. Geological Survey sampled this station on March 17, 2004 and March 15, 2005 under the Region 6 SWAMP program. Two samples had gross beta radioactivity levels of 41 and 63 pCi/L. No biological data are available for assessment of compliance with the narrative water quality objective.

Data Reference:

2007. SWAMP Data for the Amargosa Hydrologic Unit

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

There are no specific state or federal saltwater aquatic life standards or criteria for gross beta radioactivity in inland saline waters. The Lahontan Basin Plan's narrative water quality objective for radioactivity provides that: "Radionuclides shall not be present in concentrations which are deleterious to human, plant, animal, or aquatic life nor which result in the accumulation of radionuclides in the food web to an extent which presents a hazard to human, plant, animal or aquatic life." The objective also incorporates California Maximum Contaminant Levels (MUN) for radioactivity for waters designated for the MUN use. The MCLs do not apply to the Amargosa River.

Objective/Criterion Reference:

Water Quality Control Plan for the Lahontan Region (as amended)

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

One station, Amargosa River at Upper Canyon, was sampled.

Temporal Representation:

Two samples were collected on March 17, 2004 and March 15, 2005.

Environmental Conditions:

QAPP Information:

The data meet the quality assurance requirements of the SWAMP QAPP.

QAPP Information Reference(s):


DECISION ID	76532	Region 6
Amargosa River (Tecopa to Upper Canyon)

Pollutant:	Hardness as CaCO3
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2016)
Revision Status	Original
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Staff Conclusion:	Regional Board conclusion: This pollutant was considered for placement on the section 303(d) list in a previous assessment cycle. No new information was reviewed for this current assessment cycle. Therefore, the previous conclusion remains unchanged, and is as follows: 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. There are no applicable water quality standards or criteria for hardness. 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 satisfy the data quality requirements of section 6.1.4 of the Policy. 2. The data used do not satisfy the data quantity requirements of section 6.1.5 of the Policy. Only one sample per year was collected. 3. There are no applicable standards or criteria and the data cannot be assessed using 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 Staff Decision Recommendation:	This region was not assessed this cycle. All decisions have been carried over from the previous cycle and remain the same.

Line of Evidence (LOE) for Decision ID 76532, Hardness as CaCO3	Region 6
Amargosa River (Tecopa to Upper Canyon)

LOE ID:

25161

Pollutant:

Hardness as CaCO3

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Inland Saline Water Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

The U.S. Geological Survey sampled this station on March 17, 2004 and March 15, 2005 under the Region 6 SWAMP program. Two samples had hardness values of 210 and 290 ug/L CaCO3.

Data Reference:

2007. SWAMP Data for the Amargosa Hydrologic Unit

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

There are no state or federal saltwater aquatic life standards for hardness in inland saline waters.. Hardness is monitored for purposes such as determination of the applicable freshwater aquatic life criteria and standards for metals whose toxicity is hardness-dependent. The U.S. Environmental Protection Agency's 1986 "Gold Book" includes generally accepted categories of hardness. Calcium and magnesium are the major ions contributing to hardness, and hardness is generally expressed as calcium carbonate. Water with a hardness equivalent to 0-75 mg equivalent CaCO3/L is considered "soft."

Objective/Criterion Reference:

Water Quality Control Plan for the Lahontan Region (as amended)

Quality Criteria for Water 1986. United States Environmental Protection Agency. Office of Water. Regulations and Standards. Washington D.C. EPA 440/5-86-001.

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

One station, Amargosa River at Upper Canyon, was sampled.

Temporal Representation:

Two samples were taken on March 17, 2004 and March 15, 2005.

Environmental Conditions:

QAPP Information:

The data meet the quality assurance requirements of the SWAMP QAPP.

QAPP Information Reference(s):


DECISION ID	72644	Region 6
Amargosa River (Tecopa to Upper Canyon)

Pollutant:	Holmium
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2016)
Revision Status	Original
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Staff Conclusion:	Regional Board conclusion: This pollutant was considered for placement on the section 303(d) list in a previous assessment cycle. No new information was reviewed for this current assessment cycle. Therefore, the previous conclusion remains unchanged, and is as follows: 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, consisting of a single sediment sample, is available in the administrative record to assess this pollutant. There are no applicable water quality standards or criteria for holmium in the sediment of inland saline waters. 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 satisfy the data quality requirements of section 6.1.4 of the Policy. 2. The data used do not satisfy the data quantity requirements of section 6.1.5 of the Policy. 3. There are no applicable water quality standards or criteria and the single sample cannot be assessed using 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 Staff Decision Recommendation:	This region was not assessed this cycle. All decisions have been carried over from the previous cycle and remain the same.

Line of Evidence (LOE) for Decision ID 72644, Holmium	Region 6
Amargosa River (Tecopa to Upper Canyon)

LOE ID:

24864

Pollutant:

Holmium

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

None

Beneficial Use:

Inland Saline Water Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Chemical monitoring of sediments

Data Used to Assess Water Quality:

Data Reference:

2007. SWAMP Data for the Amargosa Hydrologic Unit

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

There are no state or federal standards or criteria for holmium in sediment in inland saline waters.

Objective/Criterion Reference:

Water Quality Control Plan for the Lahontan Region (as amended)

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

One station, Amargosa River at Upper Canyon, was sampled.

Temporal Representation:

One sediment sample was collected on March 15, 2005.

Environmental Conditions:

QAPP Information:

The data meet the quality assurance requirements of the SWAMP QAPP.

QAPP Information Reference(s):


DECISION ID	74216	Region 6
Amargosa River (Tecopa to Upper Canyon)

Pollutant:	Lanthanum
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2016)
Revision Status	Original
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Staff Conclusion:	Regional Board conclusion: This pollutant was considered for placement on the section 303(d) list in a previous assessment cycle. No new information was reviewed for this current assessment cycle. Therefore, the previous conclusion remains unchanged, and is as follows: 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. There are no applicable water quality standards or criteria. 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 satisfy the data quality requirements of section 6.1.4 of the Policy. 2. The single sample used does not satisfy the data quantity requirements of section 6.1.5 of the Policy. 3. There are no applicable water quality standards or criteria and the data cannot be assessed using 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 Staff Decision Recommendation:	This region was not assessed this cycle. All decisions have been carried over from the previous cycle and remain the same.

Line of Evidence (LOE) for Decision ID 74216, Lanthanum	Region 6
Amargosa River (Tecopa to Upper Canyon)

LOE ID:

24866

Pollutant:

Lanthanum

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

None

Beneficial Use:

Inland Saline Water Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Chemical monitoring of sediments

Data Used to Assess Water Quality:

Data Reference:

2007. SWAMP Data for the Amargosa Hydrologic Unit

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

There are no state or federal standards or criteria for lanthanum in sediment in inland saline waters.

Objective/Criterion Reference:

Water Quality Control Plan for the Lahontan Region (as amended)

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

One station, Amargosa River at Upper Canyon, was sampled.

Temporal Representation:

One sediment sample was collected on March 15, 2005.

Environmental Conditions:

QAPP Information:

The data meet the quality assurance requirements of the SWAMP QAPP.

QAPP Information Reference(s):


DECISION ID	73179	Region 6
Amargosa River (Tecopa to Upper Canyon)

Pollutant:	Lead
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2016)
Revision Status	Original
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Staff Conclusion:	Regional Board conclusion: This pollutant was considered for placement on the section 303(d) list in a previous assessment cycle. No new information was reviewed for this current assessment cycle. Therefore, the previous conclusion remains unchanged, and is as follows: 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. Three lines of evidence, consisting of one or two samples each, are available in the administrative record to assess this pollutant. There are no applicable saltwater aquatic life standards or criteria for lead in inland saline waters. The California Toxics Rule (CTR) saltwater standards and a sediment criterion were not exceeded. Both of these are based on toxicity to marine/estuarine organisms. 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 satisfy the data quality requirements of section 6.1.4 of the Policy. 2. The sediment data used do not satisfy the data quantity requirements of section 6.1.5 of the Policy. 3. There are no applicable water quality standards or criteria for inland saline waters. The CTR standards and the sediment criterion, based on toxicity to marine/estuarine organisms, were not exceeded and this does not exceed the allowable frequency in Table 3.1 of the Listing Policy. The single sediment sample does not meet the minimum sample number requirements 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 Staff Decision Recommendation:	This region was not assessed this cycle. All decisions have been carried over from the previous cycle and remain the same.

Line of Evidence (LOE) for Decision ID 73179, Lead	Region 6
Amargosa River (Tecopa to Upper Canyon)

LOE ID:

25020

Pollutant:

Lead

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Inland Saline Water Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

The U.S. Geological Survey sampled this station on March 17, 2004 and March 15, 2005 under the Region 6 SWAMP program. The concentrations of total lead in two samples were 0.6 and 0.41 ug/L.

Data Reference:

2007. SWAMP Data for the Amargosa Hydrologic Unit

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

There are no applicable state or federal saltwater aquatic life standards or criteria for total lead in inland saline waters.

Objective/Criterion Reference:

Water Quality Control Plan for the Lahontan Region (as amended)

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

One station, Amargosa River at Upper Canyon, was sampled.

Temporal Representation:

Two samples were collected on March 17, 2004 and March 15, 2005.

Environmental Conditions:

QAPP Information:

The data meet the quality assurance requirements of the SWAMP QAPP.

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 73179, Lead	Region 6
Amargosa River (Tecopa to Upper Canyon)

LOE ID:

24889

Pollutant:

Lead

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

None

Beneficial Use:

Inland Saline Water Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Chemical monitoring of sediments

Data Used to Assess Water Quality:

Data Reference:

2007. SWAMP Data for the Amargosa Hydrologic Unit

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

There are no state or federal standards or criteria for lead in sediment in inland saline waters. The Probable Effects Level for lead in marine and estuarine sediments is 112.18 ug/g dry weight; see Macdonald et al. (1996).

Objective/Criterion Reference:

Development and evaluation of sediment quality guidelines for Florida coastal waters. Ecotoxicology 5: 253-278

Water Quality Control Plan for the Lahontan Region (as amended)

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

One station, Amargosa River at Upper Canyon, was sampled.

Temporal Representation:

One sediment sample was collected on March 15, 2005.

Environmental Conditions:

QAPP Information:

The data meet the quality assurance requirements of the SWAMP QAPP.

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 73179, Lead	Region 6
Amargosa River (Tecopa to Upper Canyon)

LOE ID:

25021

Pollutant:

Lead

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Inland Saline Water Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

The U.S. Geological Survey sampled this station on March 17, 2004 and March 15, 2005 under the Region 6 SWAMP program. The concentrations of total lead in two samples were 0.6 and 0.41 ug/L.

Data Reference:

2007. SWAMP Data for the Amargosa Hydrologic Unit

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The California Toxics Rule saltwater aquatic life standards for lead include an acute toxicity limit of 210 ug/L and a chronic toxicity limit of 8.1 ug/L.

Objective/Criterion Reference:

Water Quality Control Plan for the Lahontan Region (as amended)

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

One station, Amargosa River at Upper Canyon, was sampled.

Temporal Representation:

Two samples were collected on March 17, 2004 and March 15, 2005.

Environmental Conditions:

QAPP Information:

The data meet the quality assurance requirements of the SWAMP QAPP.

QAPP Information Reference(s):


DECISION ID	73391	Region 6
Amargosa River (Tecopa to Upper Canyon)

Pollutant:	Lithium
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2016)
Revision Status	Original
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Staff Conclusion:	Regional Board conclusion: This pollutant was considered for placement on the section 303(d) list in a previous assessment cycle. No new information was reviewed for this current assessment cycle. Therefore, the previous conclusion remains unchanged, and is as follows: 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, consisting of a single sediment sample, is available in the administrative record to assess this pollutant. There are no applicable water quality standards or criteria for lithium in the sediment of inland saline waters. 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 satisfy the data quality requirements of section 6.1.4 of the Policy. 2. The data used do not satisfy the data quantity requirements of section 6.1.5 of the Policy. 3. There are no applicable water quality standards or criteria and the single sample cannot be assessed using 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 Staff Decision Recommendation:	This region was not assessed this cycle. All decisions have been carried over from the previous cycle and remain the same.

Line of Evidence (LOE) for Decision ID 73391, Lithium	Region 6
Amargosa River (Tecopa to Upper Canyon)

LOE ID:

24867

Pollutant:

Lithium

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

None

Beneficial Use:

Inland Saline Water Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Chemical monitoring of sediments

Data Used to Assess Water Quality:

Data Reference:

2007. SWAMP Data for the Amargosa Hydrologic Unit

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

There are no state or federal standards or criteria for lithium in sediment in inland saline waters.

Objective/Criterion Reference:

Water Quality Control Plan for the Lahontan Region (as amended)

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

One station, Amargosa River at Upper Canyon, was sampled.

Temporal Representation:

One sediment sample was collected on March 15, 2005.

Environmental Conditions:

QAPP Information:

The data meet the quality assurance requirements of the SWAMP QAPP.

QAPP Information Reference(s):


DECISION ID	74269	Region 6
Amargosa River (Tecopa to Upper Canyon)

Pollutant:	Magnesium
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2016)
Revision Status	Original
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Staff Conclusion:	Regional Board conclusion: This pollutant was considered for placement on the section 303(d) list in a previous assessment cycle. No new information was reviewed for this current assessment cycle. Therefore, the previous conclusion remains unchanged, and is as follows: 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. Three lines of evidence, consisting of one or two samples each, are available in the administrative record to assess this pollutant. There are no applicable saltwater aquatic life standards or criteria for magnesium in inland saline waters. 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 satisfy the data quality requirements of section 6.1.4 of the Policy. 2. The sediment data used do not satisfy the data quantity requirements of section 6.1.5 of the Policy. 3. There are no applicable water quality standards or criteria and the data cannot be assessed using 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 Staff Decision Recommendation:	This region was not assessed this cycle. All decisions have been carried over from the previous cycle and remain the same.

Line of Evidence (LOE) for Decision ID 74269, Magnesium	Region 6
Amargosa River (Tecopa to Upper Canyon)

LOE ID:

25167

Pollutant:

Magnesium

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Inland Saline Water Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

The U.S. Geological Survey sampled this station on March 17, 2004 and March 15, 2005 under the Region 6 SWAMP program. Two samples had total magnesium concentrations of 39 and 35.3 mg/L.

Data Reference:

2007. SWAMP Data for the Amargosa Hydrologic Unit

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

There are no state or federal saltwater aquatic life standards or criteria for total magnesium in inland saline waters.

Objective/Criterion Reference:

Water Quality Control Plan for the Lahontan Region (as amended)

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

One station, Amargosa River at Upper Canyon, was sampled.

Temporal Representation:

Two samples were taken on March 17, 2004 and March 15, 2005.

Environmental Conditions:

QAPP Information:

The data meet the quality assurance requirements of the SWAMP QAPP.

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 74269, Magnesium	Region 6
Amargosa River (Tecopa to Upper Canyon)

LOE ID:

24845

Pollutant:

Magnesium

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

None

Beneficial Use:

Inland Saline Water Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Chemical monitoring of sediments

Data Used to Assess Water Quality:

Data Reference:

2007. SWAMP Data for the Amargosa Hydrologic Unit

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

There are no state or federal standards or criteria for magnesium in sediment in inland saline waters.

Objective/Criterion Reference:

Water Quality Control Plan for the Lahontan Region (as amended)

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

One station, Amargosa River at Upper Canyon, was sampled.

Temporal Representation:

One sediment sample was collected on March 15, 2005.

Environmental Conditions:

QAPP Information:

The data meet the quality assurance requirements of the SWAMP QAPP.

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 74269, Magnesium	Region 6
Amargosa River (Tecopa to Upper Canyon)

LOE ID:

25166

Pollutant:

Magnesium

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Inland Saline Water Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

The U.S. Geological Survey sampled this station on March 17, 2004 and March 15, 2005 under the Region 6 SWAMP program. Two samples had dissolved magnesium concentrations of 30.6 and 41.9 mg/L.

Data Reference:

2007. SWAMP Data for the Amargosa Hydrologic Unit

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

There are no state or federal saltwater aquatic life standards or criteria for dissolved magnesium in inland saline waters.

Objective/Criterion Reference:

Water Quality Control Plan for the Lahontan Region (as amended)

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

One station, Amargosa River at Upper Canyon, was sampled.

Temporal Representation:

Two samples were taken on March 17, 2004 and March 15, 2005.

Environmental Conditions:

QAPP Information:

The data meet the quality assurance requirements of the SWAMP QAPP.

QAPP Information Reference(s):


DECISION ID	73681	Region 6
Amargosa River (Tecopa to Upper Canyon)

Pollutant:	Manganese
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2016)
Revision Status	Original
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Staff Conclusion:	Regional Board conclusion: This pollutant was considered for placement on the section 303(d) list in a previous assessment cycle. No new information was reviewed for this current assessment cycle. Therefore, the previous conclusion remains unchanged, and is as follows: 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. Three lines of evidence, consisting of one or two samples each, are available in the administrative record to assess this pollutant. There are no applicable saltwater aquatic life standards or criteria for manganese in inland saline waters. 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 satisfy the data quality requirements of section 6.1.4 of the Policy. 2. The sediment data used do not satisfy the data quantity requirements of section 6.1.5 of the Policy. 3. There are no applicable water quality standards or criteria and the data cannot be assessed using 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 Staff Decision Recommendation:	This region was not assessed this cycle. All decisions have been carried over from the previous cycle and remain the same.

Line of Evidence (LOE) for Decision ID 73681, Manganese	Region 6
Amargosa River (Tecopa to Upper Canyon)

LOE ID:

25023

Pollutant:

Manganese

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Inland Saline Water Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

The U.S. Geological Survey sampled this station on March 17, 2004 and March 15, 2005 under the Region 6 SWAMP program. The concentrations of dissolved manganee in two samples were 12.6 and 85.ug/L.

Data Reference:

2007. SWAMP Data for the Amargosa Hydrologic Unit

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

There are no applicable state or federal saltwater aquatic life standards or criteria for dissolved manganese in inland saline waters.

Objective/Criterion Reference:

Water Quality Control Plan for the Lahontan Region (as amended)

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

One station, Amargosa River at Upper Canyon, was sampled.

Temporal Representation:

Two samples were collected on Marh 17, 2004 and March 15, 2005.

Environmental Conditions:

QAPP Information:

The data meet the quality assurance requirements of the SWAMP QAPP.

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 73681, Manganese	Region 6
Amargosa River (Tecopa to Upper Canyon)

LOE ID:

24868

Pollutant:

Manganese

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

None

Beneficial Use:

Inland Saline Water Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Chemical monitoring of sediments

Data Used to Assess Water Quality:

Data Reference:

2007. SWAMP Data for the Amargosa Hydrologic Unit

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

There are no state or federal standards or criteria for manganese in sediment in inland saline waters.

Objective/Criterion Reference:

Water Quality Control Plan for the Lahontan Region (as amended)

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

One station, Amargosa River at Upper Canyon, was sampled.

Temporal Representation:

One sediment sample was collected on March 15, 2005.

Environmental Conditions:

QAPP Information:

The data meet the quality assurance requirements of the SWAMP QAPP.

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 73681, Manganese	Region 6
Amargosa River (Tecopa to Upper Canyon)

LOE ID:

25022

Pollutant:

Manganese

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Inland Saline Water Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

The U.S. Geological Survey sampled this station on March 17, 2004 and March 15, 2005 under the Region 6 SWAMP program. The concentrations of total manganee in two samples were 34 and 94 ug/L.

Data Reference:

2007. SWAMP Data for the Amargosa Hydrologic Unit

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

There are no applicable state or federal saltwater aquatic life standards or criteria for total manganese in inland saline waters.

Objective/Criterion Reference:

Water Quality Control Plan for the Lahontan Region (as amended)

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

One station, Amargosa River at Upper Canyon, was sampled.

Temporal Representation:

Two samples were collected on March 17, 2004 and March 15, 2005.

Environmental Conditions:

QAPP Information:

The data meet the quality assurance requirements of the SWAMP QAPP.

QAPP Information Reference(s):


DECISION ID	72812	Region 6
Amargosa River (Tecopa to Upper Canyon)

Pollutant:	Mercury
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2016)
Revision Status	Original
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Staff Conclusion:	Regional Board conclusion: This pollutant was considered for placement on the section 303(d) list in a previous assessment cycle. No new information was reviewed for this current assessment cycle. Therefore, the previous conclusion remains unchanged, and is as follows: 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. Three lines of evidence, consisting of one or two samples each, are available in the administrative record to assess this pollutant. There are no applicable saltwater aquatic life standards or criteria for mercury in inland saline waters. 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 satisfy the data quality requirements of section 6.1.4 of the Policy. 2. The sediment data used do not satisfy the data quantity requirements of section 6.1.5 of the Policy. 3. There are no applicable water quality standards or criteria for mercury in inland saline waters. However, the single sediment sample does not meet the minimum sample number requirements 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 Staff Decision Recommendation:	This region was not assessed this cycle. All decisions have been carried over from the previous cycle and remain the same.

Line of Evidence (LOE) for Decision ID 72812, Mercury	Region 6
Amargosa River (Tecopa to Upper Canyon)

LOE ID:

25025

Pollutant:

Mercury

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Inland Saline Water Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

The U.S. Geological Survey sampled this station on March 17, 2004 and March 15, 2005 under the Region 6 SWAMP program. One of two samples for total mercury was below the detection level and the other was an estimated value.

Data Reference:

2007. SWAMP Data for the Amargosa Hydrologic Unit

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

There are no state or federal standards or criteria for mercury for protection of aquatic life in inland saline waters.

Objective/Criterion Reference:

Water Quality Control Plan for the Lahontan Region (as amended)

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

One station, Amargosa River at Upper Canyon, was sampled.

Temporal Representation:

Two samples were collected on March 17, 2004 and March 15, 2005.

Environmental Conditions:

QAPP Information:

The data meet the quality assurance requirements of the SWAMP QAPP.

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 72812, Mercury	Region 6
Amargosa River (Tecopa to Upper Canyon)

LOE ID:

25024

Pollutant:

Mercury

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Inland Saline Water Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

The U.S. Geological Survey sampled this station on March 17, 2004 and March 15, 2005 under the Region 6 SWAMP program. One of two samples for dissolved mercury was below the detection level and the other was an estimated value.

Data Reference:

2007. SWAMP Data for the Amargosa Hydrologic Unit

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

There are no applicable state or federal saltwater aquatic life standards or criteria for dissolved mercury in inland saline waters.

Objective/Criterion Reference:

Water Quality Control Plan for the Lahontan Region (as amended)

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

One station, Amargosa River at Upper Canyon, was sampled.

Temporal Representation:

Two samples were collected on March 17, 2004 and March 15, 2005.

Environmental Conditions:

QAPP Information:

The data meet the quality assurance requirements of the SWAMP QAPP.

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 72812, Mercury	Region 6
Amargosa River (Tecopa to Upper Canyon)

LOE ID:

24891

Pollutant:

Mercury

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

None

Beneficial Use:

Inland Saline Water Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Chemical monitoring of sediments

Data Used to Assess Water Quality:

Data Reference:

2007. SWAMP Data for the Amargosa Hydrologic Unit

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

There are no state or federal standards or criteria for mercury in sediment in inland saline waters.

Objective/Criterion Reference:

Pollutants of concern in Puget Sound. EPA 910/9-91-003. Seattle, WA: U.S. Environmental Protection Agency

Water Quality Control Plan for the Lahontan Region (as amended)

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

One station, Amargosa River at Upper Canyon, was sampled.

Temporal Representation:

One sediment sample was collected on March 15, 2005.

Environmental Conditions:

QAPP Information:

The data meet the quality assurance requirements of the SWAMP QAPP.

QAPP Information Reference(s):


DECISION ID	73485	Region 6
Amargosa River (Tecopa to Upper Canyon)

Pollutant:	Neodymium
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2016)
Revision Status	Original
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Staff Conclusion:	Regional Board conclusion: This pollutant was considered for placement on the section 303(d) list in a previous assessment cycle. No new information was reviewed for this current assessment cycle. Therefore, the previous conclusion remains unchanged, and is as follows: 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. There are no applicable water quality standards or criteria. 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 satisfy the data quality requirements of section 6.1.4 of the Policy. 2. The single sample used does not satisfy the data quantity requirements of section 6.1.5 of the Policy. 3. There are no applicable water quality standards or criteria and the data cannot be assessed using 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 Staff Decision Recommendation:	This region was not assessed this cycle. All decisions have been carried over from the previous cycle and remain the same.

Line of Evidence (LOE) for Decision ID 73485, Neodymium	Region 6
Amargosa River (Tecopa to Upper Canyon)

LOE ID:

24870

Pollutant:

Neodymium

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

None

Beneficial Use:

Inland Saline Water Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Chemical monitoring of sediments

Data Used to Assess Water Quality:

Data Reference:

2007. SWAMP Data for the Amargosa Hydrologic Unit

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

There are no state or federal standards or criteria for neodymium in sediment in inland saline waters.

Objective/Criterion Reference:

Water Quality Control Plan for the Lahontan Region (as amended)

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

One station, Amargosa River at Upper Canyon, was sampled.

Temporal Representation:

One sediment sample was collected on March 15, 2005.

Environmental Conditions:

QAPP Information:

The data meet the quality assurance requirements of the SWAMP QAPP.

QAPP Information Reference(s):


DECISION ID	72909	Region 6
Amargosa River (Tecopa to Upper Canyon)

Pollutant:	Nickel
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2016)
Revision Status	Original
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Staff Conclusion:	Regional Board conclusion: This pollutant was considered for placement on the section 303(d) list in a previous assessment cycle. No new information was reviewed for this current assessment cycle. Therefore, the previous conclusion remains unchanged, and is as follows: 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. Three lines of evidence, consisting of one or two samples each, are available in the administrative record to assess this pollutant. There are no applicable saltwater aquatic life standards or criteria for nickel in inland saline waters. The California Toxics Rule (CTR)saltwater standards were not exceeded; however, tthey are based on toxicity to marine/estuarine organisms. 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 satisfy the data quality requirements of section 6.1.4 of the Policy. 2. The sediment data used do not satisfy the data quantity requirements of section 6.1.5 of the Policy. 3. There are no applicable water quality standards or criteria for inland saline waters. The two dissolved nickel samples did not exceed the CTR standards and this does not exceed the allowable frequency 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 Staff Decision Recommendation:	This region was not assessed this cycle. All decisions have been carried over from the previous cycle and remain the same.

Line of Evidence (LOE) for Decision ID 72909, Nickel	Region 6
Amargosa River (Tecopa to Upper Canyon)

LOE ID:

24883

Pollutant:

Nickel

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

None

Beneficial Use:

Inland Saline Water Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Chemical monitoring of sediments

Data Used to Assess Water Quality:

Data Reference:

2007. SWAMP Data for the Amargosa Hydrologic Unit

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

There are no state or federal standards or criteria for nickel in sediment in inland saline waters.

Objective/Criterion Reference:

Water Quality Control Plan for the Lahontan Region (as amended)

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

One station, Amargosa River at Upper Canyon, was sampled.

Temporal Representation:

One sediment sample was collected on March 15, 2005.

Environmental Conditions:

QAPP Information:

The data meet the quality assurance requirements of the SWAMP QAPP.

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 72909, Nickel	Region 6
Amargosa River (Tecopa to Upper Canyon)

LOE ID:

25028

Pollutant:

Nickel

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Inland Saline Water Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

The U.S. Geological Survey sampled this station on March 17, 2004 and March 15, 2005 under the Region 6 SWAMP program. The concentrations of dissolved nickel in two samples were 0.98 and 0.98 ug/L.

Data Reference:

2007. SWAMP Data for the Amargosa Hydrologic Unit

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The California Toxics Rule standards for dissolved nickel include an acute toxicity lmit of 74 ug/L and a chronic toxicity limit of 8.2 ug/L.

Objective/Criterion Reference:

Water Quality Control Plan for the Lahontan Region (as amended)

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

One station, Amargosa River at Upper Canyon, was sampled.

Temporal Representation:

Two samples were collected on March 17, 2004 and March 15, 2005.

Environmental Conditions:

QAPP Information:

The data meet the quality assurance requirements of the SWAMP QAPP.

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 72909, Nickel	Region 6
Amargosa River (Tecopa to Upper Canyon)

LOE ID:

25029

Pollutant:

Nickel

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Inland Saline Water Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

The U.S. Geological Survey sampled this station on March 17, 2004 and March 15, 2005 under the Region 6 SWAMP program. The concentrations of total nickel in two samples were 2.05 and 2.1 ug/L.

Data Reference:

2007. SWAMP Data for the Amargosa Hydrologic Unit

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

There are no applicable state or federal saltwater aquatic life standards or criteria for total nickel in inland saline waters.

Objective/Criterion Reference:

Water Quality Control Plan for the Lahontan Region (as amended)

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

One station, Amargosa River at Upper Canyon, was sampled.

Temporal Representation:

Two samples were collected on March 17, 2004 and March 15, 2005.

Environmental Conditions:

QAPP Information:

The data meet the quality assurance requirements of the SWAMP QAPP.

QAPP Information Reference(s):


DECISION ID	72787	Region 6
Amargosa River (Tecopa to Upper Canyon)

Pollutant:	Niobium
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2016)
Revision Status	Original
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Staff Conclusion:	Regional Board conclusion: This pollutant was considered for placement on the section 303(d) list in a previous assessment cycle. No new information was reviewed for this current assessment cycle. Therefore, the previous conclusion remains unchanged, and is as follows: 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, consisting of a single sediment sample, is available in the administrative record to assess this pollutant. There are no applicable water quality standards or criteria for niobium in the sediment of inland saline waters. 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 satisfy the data quality requirements of section 6.1.4 of the Policy. 2. The data used do not satisfy the data quantity requirements of section 6.1.5 of the Policy. 3. There are no applicable water quality standards or criteria and the single sample cannot be assessed using 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 Staff Decision Recommendation:	This region was not assessed this cycle. All decisions have been carried over from the previous cycle and remain the same.

Line of Evidence (LOE) for Decision ID 72787, Niobium	Region 6
Amargosa River (Tecopa to Upper Canyon)

LOE ID:

24871

Pollutant:

Niobium

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

None

Beneficial Use:

Inland Saline Water Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Chemical monitoring of sediments

Data Used to Assess Water Quality:

Data Reference:

2007. SWAMP Data for the Amargosa Hydrologic Unit

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

There are no state or federal standards or criteria for niobium in sediment in inland saline waters.

Objective/Criterion Reference:

Water Quality Control Plan for the Lahontan Region (as amended)

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

One station, Amargosa River at Upper Canyon, was sampled.

Temporal Representation:

One sediment sample was collected on March 15, 2005.

Environmental Conditions:

QAPP Information:

The data meet the quality assurance requirements of the SWAMP QAPP.

QAPP Information Reference(s):


DECISION ID	72706	Region 6
Amargosa River (Tecopa to Upper Canyon)

Pollutant:	Nitrate/Nitrite (Nitrite + Nitrate as N)
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2016)
Revision Status	Original
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Staff Conclusion:	Regional Board conclusion: This pollutant was considered for placement on the section 303(d) list in a previous assessment cycle. No new information was reviewed for this current assessment cycle. Therefore, the previous conclusion remains unchanged, and is as follows: 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 biological data are available for assessment whether any of the chemical samples exceeds 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 satisfy the data quality requirements of section 6.1.4 of the Policy. 2. The data used do not satisfy the data quantity requirements of section 6.1.5 of the Policy (only one sample per year is available). 3. No biological data are available for assessment of compliance with the objective and the data cannot be evaluated using 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 Staff Decision Recommendation:	This region was not assessed this cycle. All decisions have been carried over from the previous cycle and remain the same.

Line of Evidence (LOE) for Decision ID 72706, Nitrate/Nitrite (Nitrite + Nitrate as N)	Region 6
Amargosa River (Tecopa to Upper Canyon)

LOE ID:

25178

Pollutant:

Nitrate/Nitrite (Nitrite + Nitrate as N)

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Inland Saline Water Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

The U.S. Geological Survey sampled this station on March 17, 2004 and March 15, 2005 under the Region 6 SWAMP program. Two samples had nitrite plus nitrate concentrations of 0.009 and 0.002 mg/L.

Data Reference:

2007. SWAMP Data for the Amargosa Hydrologic Unit

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

There are no applicable state or federal saltwater aquatic life standards or criteria for nitrite plus nitrate. The Lahontan Basin Plan's regionwide objective for biostimulatory substances states: "Waters shall not contain biostimulatory substances in concentrations that promote aquatic growths to the extent that such growths cause nuisance or adversely affect the water for beneficial uses."

Objective/Criterion Reference:

Water Quality Control Plan for the Lahontan Region (as amended)

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

One station, Amargosa River at Upper Canyon, was sampled.

Temporal Representation:

Two samples were taken on March 17, 2004 and March 15, 2005.

Environmental Conditions:

QAPP Information:

The data meet the quality assurance requirements of the SWAMP QAPP.

QAPP Information Reference(s):


DECISION ID	70621	Region 6
Amargosa River (Tecopa to Upper Canyon)

Pollutant:	Oxygen 18/Oxygen 16 ratio
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2016)
Revision Status	Original
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Staff Conclusion:	Regional Board conclusion: This pollutant was considered for placement on the section 303(d) list in a previous assessment cycle. No new information was reviewed for this current assessment cycle. Therefore, the previous conclusion remains unchanged, and is as follows: 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. There are no applicable water quality objectives or criteria.. 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 satisfy the data quality requirements of section 6.1.4 of the Policy. 2. The data used do not satisfy the data quantity requirements of section 6.1.5 of the Policy. (Only one sample per year was collected.) 3. There are no applicable water quality standards or criteria and the data cannot be assessed using 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 Staff Decision Recommendation:	This region was not assessed this cycle. All decisions have been carried over from the previous cycle and remain the same.

Line of Evidence (LOE) for Decision ID 70621, Oxygen 18/Oxygen 16 ratio	Region 6
Amargosa River (Tecopa to Upper Canyon)

LOE ID:

27059

Pollutant:

Oxygen 18/Oxygen 16 ratio

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Inland Saline Water Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

The U.S. Geological Survey sampled this station on March 17, 2004 and March 15, 2005 under the Region 6 SWAMP program. Two samples had oxygen 18/oxygen 16 ratios of -11.82 and -11.98.

Data Reference:

2007. SWAMP Data for the Amargosa Hydrologic Unit

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

There are no specific state or federal saltwater aquatic life standards or criteria for oxygen 18/oxygen 16 ratio in inland saline waters.

Objective/Criterion Reference:

Water Quality Control Plan for the Lahontan Region (as amended)

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

One station, Amargosa River at Upper Canyon, was sampled.

Temporal Representation:

Two samples were collected on March 17, 2004 and March 15, 2005.

Environmental Conditions:

QAPP Information:

The data meet the quality assurance requirements of the SWAMP QAPP.

QAPP Information Reference(s):


DECISION ID	73274	Region 6
Amargosa River (Tecopa to Upper Canyon)

Pollutant:	Oxygen, Dissolved
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2016)
Revision Status	Original
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Staff Conclusion:	Regional Board conclusion: This pollutant was considered for placement on the section 303(d) list in a previous assessment cycle. No new information was reviewed for this current assessment cycle. Therefore, the previous conclusion remains unchanged, and is as follows: 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. Neither of the two samples exceeds 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 satisfy the data quality requirements of section 6.1.4 of the Policy. 2. The data used do not satisfy the data quantity requirements of section 6.1.5 of the Policy. 3. Neither of 2 samples exceeded the water quality objective and this does not exceed the allowable frequency listed in Table 3.2 of the Listing Policy. However, the minimum sample number requirements of Table 3.2 are not met. 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 Staff Decision Recommendation:	This region was not assessed this cycle. All decisions have been carried over from the previous cycle and remain the same.

Line of Evidence (LOE) for Decision ID 73274, Oxygen, Dissolved	Region 6
Amargosa River (Tecopa to Upper Canyon)

LOE ID:

25156

Pollutant:

Oxygen, Dissolved

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

The U.S. Geological Survey sampled this station on March 17, 2004 and March 15, 2005 under the Region 6 SWAMP program. The concentrations of dissolved oxygen in two samples were 10.4 and 10 mg/L.

Data Reference:

2007. SWAMP Data for the Amargosa Hydrologic Unit

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The applicable water quality objective, from Lahontan Basin Plan Table 3-16, is a one-day minimum of 5 ug/L.

Objective/Criterion Reference:

Water Quality Control Plan for the Lahontan Region (as amended)

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

One station, Amargosa River at Upper Canyon, was sampled.

Temporal Representation:

Two samples were collected on March 17, 2004 and March 15, 2005.

Environmental Conditions:

QAPP Information:

The data meet the quality assurance requirements of the SWAMP QAPP.

QAPP Information Reference(s):


DECISION ID	76460	Region 6
Amargosa River (Tecopa to Upper Canyon)

Pollutant:	Percent Sodium
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2016)
Revision Status	Original
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Staff Conclusion:	Regional Board conclusion: This pollutant was considered for placement on the section 303(d) list in a previous assessment cycle. No new information was reviewed for this current assessment cycle. Therefore, the previous conclusion remains unchanged, and is as follows: 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. The single sample exceeds the water quality criterion for irrigation water. To Water Board staff's knowledge the surface waters of the Amargosa River are not used for irrigation. The definition of the Agricultural Supply beneficial use includes both irrigation and livestock watering. The extent to which livestock watering is an existing use is unknown. 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 satisfy the data quality requirements of section 6.1.4 of the Policy. 2. The data used do not satisfy the data quantity requirements of section 6.1.5 of the Policy. 3. The single sample exceeded the irrigation water criterion and this does not exceed the allowable frequency listed in Table 3.2 of the Listing Policy. The minimum sample number requirement of Table 3.2 was not met. 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 Staff Decision Recommendation:	This region was not assessed this cycle. All decisions have been carried over from the previous cycle and remain the same.

Line of Evidence (LOE) for Decision ID 76460, Percent Sodium	Region 6
Amargosa River (Tecopa to Upper Canyon)

LOE ID:

25226

Pollutant:

Percent Sodium

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Agricultural Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

The U.S. Geological Survey sampled this station on March 15, 2005 under the Region 6 SWAMP program. Percent sodium in one sample was 81 percent.

Data Reference:

2007. SWAMP Data for the Amargosa Hydrologic Unit

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

There is no site-specific water quality objective for Percent Sodium in the Amargosa River. Percent sodium is an older and now obsolete criterion for irrigation waters. It is an index for the percentage of sodium ion in the sum of the concentrations of sodium, calcium, magnesium and potassium ions. Water with percent sodium greater than 70 to 75 percent is considered to be unsuitable for irrigation.

Objective/Criterion Reference:

Water Quality Control Plan for the Lahontan Region (as amended)

Water Quality Criteria. Second Edition. California State Water Resources Control Board. Publication 3-A

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

One station, Amargosa River at Upper Canyon, was sampled.

Temporal Representation:

One sample was collected on March 15, 2005

Environmental Conditions:

The Amargosa River flows into California from Nevada and terminates in Death Valley. It is mostly ephemeral but there are perennial reaches. There is great seasonal and annual variability in flows. Most of the watershed is U.S. Bureau of Land Management or National Park land.

To Lahontan Water Board staff's knowledge, the Amargosa River is not used for irrigated agriculture.

The Amargosa River is not designated for the Municipal and Domestic Supply (MUN) beneficial use. The MUN use designation was removed in Basin Plan amendments that took effect in 2002. The rationale for removing the use included naturally high salinity and levels of toxic substances such as arsenic, and fluctuating water quantity that would make the river an unreliable supply if treatment were feasible.

The perennial reaches of the Amargosa River and the associated riparian areas support a complex of rare, threatened or endangered fish and wildlife species. To Lahontan Water Board staff¿s knowledge, there are no salmonids in the river and there is no warm water fishery for human consumption.

QAPP Information:

The data meet the quality assurance requirements of the SWAMP QAPP.

QAPP Information Reference(s):


DECISION ID	73182	Region 6
Amargosa River (Tecopa to Upper Canyon)

Pollutant:	Phosphate
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2016)
Revision Status	Original
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Staff Conclusion:	Regional Board conclusion: This pollutant was considered for placement on the section 303(d) list in a previous assessment cycle. No new information was reviewed for this current assessment cycle. Therefore, the previous conclusion remains unchanged, and is as follows: 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 biological data are available for assessment whether any of the chemical samples exceeds 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 satisfy the data quality requirements of section 6.1.4 of the Policy. 2. The data used do not satisfy the data quantity requirements of section 6.1.5 of the Policy (only one sample per year is available). 3. No biological data are available for assessment of compliance with the objective and the data cannot be evaluated using 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 Staff Decision Recommendation:	This region was not assessed this cycle. All decisions have been carried over from the previous cycle and remain the same.

Line of Evidence (LOE) for Decision ID 73182, Phosphate	Region 6
Amargosa River (Tecopa to Upper Canyon)

LOE ID:

25180

Pollutant:

Phosphate

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Inland Saline Water Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

The U.S. Geological Survey sampled this station on March 17, 2004 and March 15, 2005 under the Region 6 SWAMP program. Two samples had dissolved phosphate concentrations of 0.255 and 0.185 mg/L.

Data Reference:

2007. SWAMP Data for the Amargosa Hydrologic Unit

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

There are no applicable state or federal saltwater aquatic life standards or criteria for dissolved phosphate. The Lahontan Basin Plan's regionwide objective for biostimulatory substances states: "Waters shall not contain biostimulatory substances in concentrations that promote aquatic growths to the extent that such growths cause nuisance or adversely affect the water for beneficial uses."

Objective/Criterion Reference:

Water Quality Control Plan for the Lahontan Region (as amended)

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

One station, Amargosa River at Upper Canyon, was sampled.

Temporal Representation:

Two samples were taken on March 17, 2004 and March 15, 2005.

Environmental Conditions:

QAPP Information:

The data meet the quality assurance requirements of the SWAMP QAPP.

QAPP Information Reference(s):


DECISION ID	72594	Region 6
Amargosa River (Tecopa to Upper Canyon)

Pollutant:	Phosphorus
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2016)
Revision Status	Original
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Staff Conclusion:	Regional Board conclusion: This pollutant was considered for placement on the section 303(d) list in a previous assessment cycle. No new information was reviewed for this current assessment cycle. Therefore, the previous conclusion remains unchanged, and is as follows: 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. There are no applicable water quality standards or criteria for phosphorus in sediment. No biological data are available for assessment whether any of the total phosphorus samples in water exceeds the water quality objective for biostimulatory substances. 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 do not satisfy the data quality requirements of section 6.1.4 of the Policy due to an error in the SWAMP QAPP regarding holding times for total phosphorus samples. 2. The data used do not satisfy the data quantity requirements of section 6.1.5 of the Policy. 3. There are no applicable standards for phosphorus in sediment and there are no biological data available for assessment of compliance with the wate quality objective. The data cannot be assessed using 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 Staff Decision Recommendation:	This region was not assessed this cycle. All decisions have been carried over from the previous cycle and remain the same.

Line of Evidence (LOE) for Decision ID 72594, Phosphorus	Region 6
Amargosa River (Tecopa to Upper Canyon)

LOE ID:

25181

Pollutant:

Phosphorus

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Inland Saline Water Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

The U.S. Geological Survey sampled this station on March 17, 2004 and March 15, 2005 under the Region 6 SWAMP program. Two samples had total phosphorus concentrations of 0.312 and 0.246 mg/L.

Data Reference:

2007. SWAMP Data for the Amargosa Hydrologic Unit

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

There are no applicable state or federal saltwater aquatic life standards or criteria for total phosphorus for inland surface waters. The Lahontan Basin Plan's regionwide objective for biostimulatory substances states: "Waters shall not contain biostimulatory substances in concentrations that promote aquatic growths to the extent that such growths cause nuisance or adversely affect the water for beneficial uses."

Objective/Criterion Reference:

Water Quality Control Plan for the Lahontan Region (as amended)

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

One station, Amargosa River at Upper Canyon, was sampled.

Temporal Representation:

Two samples were taken on March 17, 2004 and March 15, 2005.

Environmental Conditions:

QAPP Information:

Sampling and analysis were done according to the SWAMP QAPP. However, in July 2009 an error was discovered in the QAPP related to holding times for total phosphorus samples that affects the validity of data for the Lahontan Region The holding time for samples that are not acid-preserved.should be 48 hours rather than 28 days as indicated in the QAPP. "Low level" phosphorus analyses, without acid preservation, are used in the Lahontan Region's SWAMP program. .

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 72594, Phosphorus	Region 6
Amargosa River (Tecopa to Upper Canyon)

LOE ID:

24848

Pollutant:

Phosphorus

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

None

Beneficial Use:

Inland Saline Water Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Chemical monitoring of sediments

Data Used to Assess Water Quality:

Data Reference:

2007. SWAMP Data for the Amargosa Hydrologic Unit

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

There are no state or federal standards or criteria for phosphorus in sediment in inland saline waters.

Objective/Criterion Reference:

Water Quality Control Plan for the Lahontan Region (as amended)

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

One station, Amargosa River at Upper Canyon, was sampled.

Temporal Representation:

One sediment sample was collected on March 15, 2005.

Environmental Conditions:

QAPP Information:

QAPP Information Reference(s):


DECISION ID	74206	Region 6
Amargosa River (Tecopa to Upper Canyon)

Pollutant:	Potassium
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2016)
Revision Status	Original
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Staff Conclusion:	Regional Board conclusion: This pollutant was considered for placement on the section 303(d) list in a previous assessment cycle. No new information was reviewed for this current assessment cycle. Therefore, the previous conclusion remains unchanged, and is as follows: 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. There are no applicable water quality standards or criteria for this pollutant in inland saline waters. 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 satisfy the data quality requirements of section 6.1.4 of the Policy. 2. The data used do not satisfy the data quantity requirements of section 6.1.5 of the Policy. 3. There are no applicable water quality standards or criteria, and the data do not meet the minimum sample number requirements of 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 Staff Decision Recommendation:	This region was not assessed this cycle. All decisions have been carried over from the previous cycle and remain the same.

Line of Evidence (LOE) for Decision ID 74206, Potassium	Region 6
Amargosa River (Tecopa to Upper Canyon)

LOE ID:

24846

Pollutant:

Potassium

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

None

Beneficial Use:

Inland Saline Water Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Chemical monitoring of sediments

Data Used to Assess Water Quality:

Data Reference:

2007. SWAMP Data for the Amargosa Hydrologic Unit

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

There are no state or federal standards or criteria for potassium in sediment in inland saline waters.

Objective/Criterion Reference:

Water Quality Control Plan for the Lahontan Region (as amended)

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

One station, Amargosa River at Upper Canyon, was sampled.

Temporal Representation:

One sediment sample was collected on March 15, 2005.

Environmental Conditions:

QAPP Information:

The data meet the quality assurance requirements of the SWAMP QAPP.

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 74206, Potassium	Region 6
Amargosa River (Tecopa to Upper Canyon)

LOE ID:

25168

Pollutant:

Potassium

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Inland Saline Water Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

The U.S. Geological Survey sampled this station on March 17, 2004 and March 15, 2005 under the Region 6 SWAMP program. Two samples had dissolved potassium concentrations of 43.2 and 40.7 mg/L.

Data Reference:

2007. SWAMP Data for the Amargosa Hydrologic Unit

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

There are no state or federal saltwater aquatic life standards or criteria for dissolved potassium in inland saline waters.

Objective/Criterion Reference:

Water Quality Control Plan for the Lahontan Region (as amended)

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

One station, Amargosa River at Upper Canyon, was sampled.

Temporal Representation:

Two samples were taken on March 17, 2004 and March 15, 2005.

Environmental Conditions:

QAPP Information:

The data meet the quality assurance requirements of the SWAMP QAPP.

QAPP Information Reference(s):


DECISION ID	75543	Region 6
Amargosa River (Tecopa to Upper Canyon)

Pollutant:	Radium 226
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2016)
Revision Status	Original
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Staff Conclusion:	Regional Board conclusion: This pollutant was considered for placement on the section 303(d) list in a previous assessment cycle. No new information was reviewed for this current assessment cycle. Therefore, the previous conclusion remains unchanged, and is as follows: 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 biological data are available for assessment whether either of the two samples exceeds 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 satisfy the data quality requirements of section 6.1.4 of the Policy. 2. The data used do not satisfy the data quantity requirements of section 6.1.5 of the Policy. 3. No biological data are available for assessment of compliance with the water quality objective and the data cannot be assessed using 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 Staff Decision Recommendation:	This region was not assessed this cycle. All decisions have been carried over from the previous cycle and remain the same.

Line of Evidence (LOE) for Decision ID 75543, Radium 226	Region 6
Amargosa River (Tecopa to Upper Canyon)

LOE ID:

27060

Pollutant:

Radium 226

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Inland Saline Water Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

The U.S. Geological Survey sampled this station on March 17, 2004 and March 15, 2005 under the Region 6 SWAMP program. Two samples had radium 226 levels of 0.06 and 0.093 pCi/L. No biological data are available for assessment of compliance with the narrative water quality objective.

Data Reference:

2007. SWAMP Data for the Amargosa Hydrologic Unit

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

There are no specific state or federal saltwater aquatic life standards or criteria for radium 226 in inland saline waters. The Lahontan Basin Plan's narrative water quality objective for radioactivity provides that: "Radionuclides shall not be present in concentrations which are deleterious to human, plant, animal, or aquatic life nor which result in the accumulation of radionuclides in the food web to an extent which presents a hazard to human, plant, animal or aquatic life." The objective also incorporates California Maximum Contaminant Levels (MUN) for radioactivity for waters designated for the MUN use. The MCLs do not apply to the Amargosa River.

Objective/Criterion Reference:

Water Quality Control Plan for the Lahontan Region (as amended)

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

One station, Amargosa River at Upper Canyon, was sampled.

Temporal Representation:

Two samples were collected on March 17, 2004 and March 15, 2005.

Environmental Conditions:

QAPP Information:

The data meet the quality assurance requirements of the SWAMP QAPP.

QAPP Information Reference(s):


DECISION ID	72989	Region 6
Amargosa River (Tecopa to Upper Canyon)

Pollutant:	Scandium
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2016)
Revision Status	Original
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Staff Conclusion:	Regional Board conclusion: This pollutant was considered for placement on the section 303(d) list in a previous assessment cycle. No new information was reviewed for this current assessment cycle. Therefore, the previous conclusion remains unchanged, and is as follows: 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, consisting of a single sediment sample, is available in the administrative record to assess this pollutant. There are no applicable water quality standards or criteria for scandium in the sediment of inland saline waters. 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 satisfy the data quality requirements of section 6.1.4 of the Policy. 2. The data used do not satisfy the data quantity requirements of section 6.1.5 of the Policy. 3. There are no applicable water quality standards or criteria and the single sample cannot be assessed using 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 Staff Decision Recommendation:	This region was not assessed this cycle. All decisions have been carried over from the previous cycle and remain the same.

Line of Evidence (LOE) for Decision ID 72989, Scandium	Region 6
Amargosa River (Tecopa to Upper Canyon)

LOE ID:

24872

Pollutant:

Scandium

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

None

Beneficial Use:

Inland Saline Water Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Chemical monitoring of sediments

Data Used to Assess Water Quality:

Data Reference:

2007. SWAMP Data for the Amargosa Hydrologic Unit

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

There are no state or federal standards or criteria for scandium in sediment in inland saline waters.

Objective/Criterion Reference:

Water Quality Control Plan for the Lahontan Region (as amended)

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

One station, Amargosa River at Upper Canyon, was sampled.

Temporal Representation:

One sediment sample was collected on March 15, 2005.

Environmental Conditions:

QAPP Information:

The data meet the quality assurance requirements of the SWAMP QAPP.

QAPP Information Reference(s):


DECISION ID	76048	Region 6
Amargosa River (Tecopa to Upper Canyon)

Pollutant:	Sediment
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2016)
Revision Status	Original
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Staff Conclusion:	Regional Board conclusion: This pollutant was considered for placement on the section 303(d) list in a previous assessment cycle. No new information was reviewed for this current assessment cycle. Therefore, the previous conclusion remains unchanged, and is as follows: The Lahontan Basin Plan's narrative water quality objective is an antidegradation based objective that provides that there shall be no increases in suspended sediment concentrations or loads. This pollutant is being considered for placement on the section 303(d) list under section 3.10 of the Listing Policy, which deals with trends in water quality. One line of evidence, based on two annual samples, is available in the administrative record to assess this pollutant. It includes two suspended sediment concentration values and two suspended sediment load values calculated from instantaneous discharge measurements. Suspended sediment concentrations and loads are dependent on flows and can change rapidly over a short time during storm runoff events. Annual samples are insufficient to capture these short term events and therefore are insufficient to define natural background suspended sediment concentrations and loads, or to detect trends. Listing Policy Section 3.10 requires that natural background conditions be established. 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 satisfy the data quality requirements of section 6.1.4 of the Policy. 2. Sampling frequency was insufficient to establish natural background conditions and therefore does not meet the requirements of Listing Policy Section 3.10. 3. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

Regional Board Staff Decision Recommendation:	This region was not assessed this cycle. All decisions have been carried over from the previous cycle and remain the same.

Line of Evidence (LOE) for Decision ID 76048, Sediment	Region 6
Amargosa River (Tecopa to Upper Canyon)

LOE ID:

27063

Pollutant:

Sediment

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Inland Saline Water Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

The U.S. Geological Survey sampled this station on March 17, 2004 and March 15, 2005 under the Region 6 SWAMP program. Suspended sediment concentrations in two samples were 22 and 15 mg/L. One of the instantaneous flow figures was an estimate and the other was 3 cubic feet per second. One of the calculated suspended sediment loads was an estimate and the other was 0.12 tons per day.

Data Reference:

2007. SWAMP Data for the Amargosa Hydrologic Unit

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The Lahontan Basin Plan's narrative objective states:
"The suspended sediment load and suspended sediment discharge rate of surface waters shall not be altered in such a manner as to cause nuisance or adversely affect the water for beneficial uses."

Objective/Criterion Reference:

Water Quality Control Plan for the Lahontan Region (as amended)

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

One station, Amargosa River at Upper Canyon, was sampled.

Temporal Representation:

Two samples were collected on March 17, 2004 and March 15, 2005.

Environmental Conditions:

QAPP Information:

The data meet the quality assurance requirements of the SWAMP QAPP.

QAPP Information Reference(s):


DECISION ID	73243	Region 6
Amargosa River (Tecopa to Upper Canyon)

Pollutant:	Silica
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2016)
Revision Status	Original
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Staff Conclusion:	Regional Board conclusion: This pollutant was considered for placement on the section 303(d) list in a previous assessment cycle. No new information was reviewed for this current assessment cycle. Therefore, the previous conclusion remains unchanged, and is as follows: 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, consisting of two samples, is available in the administrative record to assess this pollutant. There are no applicable water quality standards or criteria for silica in inland saline waters. 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 satisfy the data quality requirements of section 6.1.4 of the Policy. 2. The data used do not satisfy the data quantity requirements of section 6.1.5 of the Policy. 3. There are no applicable water quality standards or criteria and the data cannot be assessed using 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 Staff Decision Recommendation:	This region was not assessed this cycle. All decisions have been carried over from the previous cycle and remain the same.

Line of Evidence (LOE) for Decision ID 73243, Silica	Region 6
Amargosa River (Tecopa to Upper Canyon)

LOE ID:

25174

Pollutant:

Silica

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Inland Saline Water Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

The U.S. Geological Survey sampled this station on March 17, 2004 and March 15, 2005 under the Region 6 SWAMP program. Two samples had dissolved silica concentrations of 60.8 and 58 mg/L.

Data Reference:

2007. SWAMP Data for the Amargosa Hydrologic Unit

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

There are no state or federal saltwater aquatic life standards or criteria for dissolved silica in inland saline waters.

Objective/Criterion Reference:

Water Quality Control Plan for the Lahontan Region (as amended)

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

One station, Amargosa River at Upper Canyon, was sampled.

Temporal Representation:

Two samples were taken on March 17, 2004 and March 15, 2005.

Environmental Conditions:

QAPP Information:

The data meet the quality assurance requirements of the SWAMP QAPP.

QAPP Information Reference(s):


DECISION ID	73575	Region 6
Amargosa River (Tecopa to Upper Canyon)

Pollutant:	Silver
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2016)
Revision Status	Original
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Staff Conclusion:	Regional Board conclusion: This pollutant was considered for placement on the section 303(d) list in a previous assessment cycle. No new information was reviewed for this current assessment cycle. Therefore, the previous conclusion remains unchanged, and is as follows: 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. Three lines of evidence, consisting of one or two samples each, are available in the administrative record to assess this pollutant. There are no applicable saltwater aquatic life standards or criteria for silver in inland saline waters. The California Toxics Rule saltwater standard and a sediment criterion were not exceeded. However, both are based on toxicity to marine/estuarine organisms. 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 satisfy the data quality requirements of section 6.1.4 of the Policy. 2. The sediment data used do not satisfy the data quantity requirements of section 6.1.5 of the Policy. 3. There are no applicable water quality standards or criteria for inland saline waters. The saltwater standard and criterion, based on toxicity to marine/estuarine organisms, were not exceeded, and this does not exceed the allowable frequency in Table 3.1 of the Listing Policy. However, the single sediment sample does not meet the minimum sample number requirements 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 Staff Decision Recommendation:	This region was not assessed this cycle. All decisions have been carried over from the previous cycle and remain the same.

Line of Evidence (LOE) for Decision ID 73575, Silver	Region 6
Amargosa River (Tecopa to Upper Canyon)

LOE ID:

24890

Pollutant:

Silver

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

None

Beneficial Use:

Inland Saline Water Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Chemical monitoring of sediments

Data Used to Assess Water Quality:

Data Reference:

2007. SWAMP Data for the Amargosa Hydrologic Unit

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

There are no state or federal standards or criteria for silver in sediment in inland saline waters. The Probable Effects Level for silver in marine and estuarine sediments is 1.77 ug/g dry weight; see Macdonald et al. (1996).

Objective/Criterion Reference:

Development and evaluation of sediment quality guidelines for Florida coastal waters. Ecotoxicology 5: 253-278

Water Quality Control Plan for the Lahontan Region (as amended)

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

One station, Amargosa River at Upper Canyon, was sampled.

Temporal Representation:

One sediment sample was collected on March 15, 2005.

Environmental Conditions:

QAPP Information:

The data meet the quality assurance requirements of the SWAMP QAPP.

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 73575, Silver	Region 6
Amargosa River (Tecopa to Upper Canyon)

LOE ID:

25033

Pollutant:

Silver

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Inland Saline Water Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

The U.S. Geological Survey sampled this station on March 17, 2004 and March 15, 2005 under the Region 6 SWAMP program. Concentrations of dissolved silver in two samples were both below the detection level.

Data Reference:

2007. SWAMP Data for the Amargosa Hydrologic Unit

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The California Toxics Rule standard for dissolved silver is an acute toxicity limit of 1.9 ug/L.

Objective/Criterion Reference:

Water Quality Control Plan for the Lahontan Region (as amended)

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

One station, Amargosa River at Upper Canyon, was sampled.

Temporal Representation:

Two samples were collected on March 17, 2004 and March 15, 2005.

Environmental Conditions:

QAPP Information:

The data meet the quality assurance requirements of the SWAMP QAPP.

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 73575, Silver	Region 6
Amargosa River (Tecopa to Upper Canyon)

LOE ID:

25032

Pollutant:

Silver

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Inland Saline Water Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

The U.S. Geological Survey sampled this station on March 17, 2004 and March 15, 2005 under the Region 6 SWAMP program. Concentrations of total silver in two samples were both below the detection level.

Data Reference:

2007. SWAMP Data for the Amargosa Hydrologic Unit

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

There are no state or federal saltwater aquatic life standards or criteria for total silver.

Objective/Criterion Reference:

Water Quality Control Plan for the Lahontan Region (as amended)

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

One station, Amargosa River at Upper Canyon, was sampled.

Temporal Representation:

Two samples were collected on March 17, 2004 and March 15, 2005.

Environmental Conditions:

QAPP Information:

The data meet the quality assurance requirements of the SWAMP QAPP.

QAPP Information Reference(s):


DECISION ID	72938	Region 6
Amargosa River (Tecopa to Upper Canyon)

Pollutant:	Specific Conductance
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2016)
Revision Status	Original
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Staff Conclusion:	Regional Board conclusion: This pollutant was considered for placement on the section 303(d) list in a previous assessment cycle. No new information was reviewed for this current assessment cycle. Therefore, the previous conclusion remains unchanged, and is as follows: 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, consisting of two samples, is available in the administrative record to assess this pollutant. There are no applicable water quality standards or criteria for specific conductance in inland saline waters that are not designated for the MUN beneficial use. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the section 303(d) list in the Water Quality Limited Segments category. This conclusion is based on the staff findings that: 1. The data used satisfy the data quality requirements of section 6.1.4 of the Policy. 2. The data used do not satisfy the data quantity requirements of section 6.1.5 of the Policy. 3. There are no applicable water quality standards or criteria and the data cannot be assessed using 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 Staff Decision Recommendation:	This region was not assessed this cycle. All decisions have been carried over from the previous cycle and remain the same.

Line of Evidence (LOE) for Decision ID 72938, Specific Conductance	Region 6
Amargosa River (Tecopa to Upper Canyon)

LOE ID:

25160

Pollutant:

Specific Conductance

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Inland Saline Water Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

The U.S. Geological Survey sampled this station on March 17, 2004 and March 15, 2005 under the Region 6 SWAMP program. Specific conductance values in two measurements were 3820 and 3260 microsiemens per centimeter (uS/cm)..

Data Reference:

2007. SWAMP Data for the Amargosa Hydrologic Unit

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

There are no state or federal saltwater aquatic life standards or criteria for specific conductance in inland saline waters.

Objective/Criterion Reference:

Water Quality Control Plan for the Lahontan Region (as amended)

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

One station, Amargosa River at Upper Canyon, was sampled.

Temporal Representation:

Two measurements of specific conductance were taken on March 17, 2004 and March 15, 2005.

Environmental Conditions:

QAPP Information:

The data meet the quality assurance requirements of the SWAMP QAPP.

QAPP Information Reference(s):


DECISION ID	74171	Region 6
Amargosa River (Tecopa to Upper Canyon)

Pollutant:	Strontium
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2016)
Revision Status	Original
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Staff Conclusion:	Regional Board conclusion: This pollutant was considered for placement on the section 303(d) list in a previous assessment cycle. No new information was reviewed for this current assessment cycle. Therefore, the previous conclusion remains unchanged, and is as follows: 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. There are no applicable water quality standards or criteria. 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 satisfy the data quality requirements of section 6.1.4 of the Policy. 2. The single sample used does not satisfy the data quantity requirements of section 6.1.5 of the Policy. 3. There are no applicable water quality standards or criteria and the data cannot be assessed using 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 Staff Decision Recommendation:	This region was not assessed this cycle. All decisions have been carried over from the previous cycle and remain the same.

Line of Evidence (LOE) for Decision ID 74171, Strontium	Region 6
Amargosa River (Tecopa to Upper Canyon)

LOE ID:

24874

Pollutant:

Strontium

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

None

Beneficial Use:

Inland Saline Water Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Chemical monitoring of sediments

Data Used to Assess Water Quality:

Data Reference:

2007. SWAMP Data for the Amargosa Hydrologic Unit

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

There are no state or federal standards or criteria for strontium in sediment in inland saline waters.

Objective/Criterion Reference:

Water Quality Control Plan for the Lahontan Region (as amended)

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

One station, Amargosa River at Upper Canyon, was sampled.

Temporal Representation:

One sediment sample was collected on March 15, 2005.

Environmental Conditions:

QAPP Information:

The data meet the quality assurance requirements of the SWAMP QAPP.

QAPP Information Reference(s):


DECISION ID	72687	Region 6
Amargosa River (Tecopa to Upper Canyon)

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)(2016)
Revision Status	Original
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Staff Conclusion:	Regional Board conclusion: This pollutant was considered for placement on the section 303(d) list in a previous assessment cycle. No new information was reviewed for this current assessment cycle. Therefore, the previous conclusion remains unchanged, and is as follows: 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, consisting of two samples, is available in the administrative record to assess this pollutant. There are no applicable water quality standards or criteria for sulfate in inland saline waters. 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 satisfy the data quality requirements of section 6.1.4 of the Policy. 2. The data used do not satisfy the data quantity requirements of section 6.1.5 of the Policy. 3. There are no applicable water quality standards or criteria and the data cannot be assessed using 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 Staff Decision Recommendation:	This region was not assessed this cycle. All decisions have been carried over from the previous cycle and remain the same.

Line of Evidence (LOE) for Decision ID 72687, Sulfates	Region 6
Amargosa River (Tecopa to Upper Canyon)

LOE ID:

25175

Pollutant:

Sulfates

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Inland Saline Water Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

The U.S. Geological Survey sampled this station on March 17, 2004 and March 15, 2005 under the Region 6 SWAMP program. Two samples had dissolved sulfate concentrations of 690 and 680 mg/L.

Data Reference:

2007. SWAMP Data for the Amargosa Hydrologic Unit

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

There are no state or federal saltwater aquatic life standards or criteria for dissolved sulfate in inland saline waters.

Objective/Criterion Reference:

Water Quality Control Plan for the Lahontan Region (as amended)

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

One station, Amargosa River at Upper Canyon, was sampled.

Temporal Representation:

Two samples were taken on March 17, 2004 and March 15, 2005.

Environmental Conditions:

QAPP Information:

The data meet the quality assurance requirements of the SWAMP QAPP.

QAPP Information Reference(s):


DECISION ID	73246	Region 6
Amargosa River (Tecopa to Upper Canyon)

Pollutant:	Sulfur
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2016)
Revision Status	Original
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Staff Conclusion:	Regional Board conclusion: This pollutant was considered for placement on the section 303(d) list in a previous assessment cycle. No new information was reviewed for this current assessment cycle. Therefore, the previous conclusion remains unchanged, and is as follows: 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, consisting of a single sediment sample, is available in the administrative record to assess this pollutant. There are no applicable water quality standards or criteria for sulfur in the sediment of inland saline waters. 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 satisfy the data quality requirements of section 6.1.4 of the Policy. 2. The data used do not satisfy the data quantity requirements of section 6.1.5 of the Policy. 3. There are no applicable water quality standards or criteria and the single sample cannot be assessed using 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 Staff Decision Recommendation:	This region was not assessed this cycle. All decisions have been carried over from the previous cycle and remain the same.

Line of Evidence (LOE) for Decision ID 73246, Sulfur	Region 6
Amargosa River (Tecopa to Upper Canyon)

LOE ID:

25186

Pollutant:

Sulfur

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

None

Beneficial Use:

Inland Saline Water Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Chemical monitoring of sediments

Data Used to Assess Water Quality:

Data Reference:

2007. SWAMP Data for the Amargosa Hydrologic Unit

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

There are no state or federal saltwater standards or criteria for sulfur in sediment in inland saline waters.

Objective/Criterion Reference:

Water Quality Control Plan for the Lahontan Region (as amended)

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

One station, Amargosa River at Upper Canyon, was sampled.

Temporal Representation:

One sediment sample was collected on March 15, 2005.

Environmental Conditions:

QAPP Information:

The data meet the quality assurance requirements of the SWAMP QAPP.

QAPP Information Reference(s):


DECISION ID	74161	Region 6
Amargosa River (Tecopa to Upper Canyon)

Pollutant:	Tantalum
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2016)
Revision Status	Original
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Staff Conclusion:	Regional Board conclusion: This pollutant was considered for placement on the section 303(d) list in a previous assessment cycle. No new information was reviewed for this current assessment cycle. Therefore, the previous conclusion remains unchanged, and is as follows: 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. There are no applicable water quality standards or criteria. 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 satisfy the data quality requirements of section 6.1.4 of the Policy. 2. The single sample used does not satisfy the data quantity requirements of section 6.1.5 of the Policy. 3. There are no applicable water quality standards or criteria and the data cannot be assessed using 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 Staff Decision Recommendation:	This region was not assessed this cycle. All decisions have been carried over from the previous cycle and remain the same.

Line of Evidence (LOE) for Decision ID 74161, Tantalum	Region 6
Amargosa River (Tecopa to Upper Canyon)

LOE ID:

24875

Pollutant:

Tantalum

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

None

Beneficial Use:

Inland Saline Water Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Chemical monitoring of sediments

Data Used to Assess Water Quality:

Data Reference:

2007. SWAMP Data for the Amargosa Hydrologic Unit

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

There are no state or federal standards or criteria for tantalum in sediment in inland saline waters.

Objective/Criterion Reference:

Water Quality Control Plan for the Lahontan Region (as amended)

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

One station, Amargosa River at Upper Canyon, was sampled.

Temporal Representation:

One sediment sample was collected on March 15, 2005.

Environmental Conditions:

QAPP Information:

The data meet the quality assurance requirements of the SWAMP QAPP.

QAPP Information Reference(s):


DECISION ID	74093	Region 6
Amargosa River (Tecopa to Upper Canyon)

Pollutant:	Temperature, water
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2016)
Revision Status	Original
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Staff Conclusion:	Regional Board conclusion: This pollutant was considered for placement on the section 303(d) list in a previous assessment cycle. No new information was reviewed for this current assessment cycle. Therefore, the previous conclusion remains unchanged, and is as follows: The Lahontan Basin Plan's narrative temperature objective is an antidegradation-based objective that requires that there be no change in temperature in waters designated for the Warm Freshwater Habitat (WARM) beneficial use. The objective does not include specific numerical limits for protection of the WARM use. Listing Policy Section 3.10 contains directions for assessment based on trends in water quality. These directions include requirements to establish specific baseline conditions and specify the influence of seasonal and interannual effects. One line of evidence, consisting of two annual samples, is available to support this decision. There are not enough temperature samples to establish baseline conditions (including diel, seasonal, annual and interannual variations in temperature) or to detect declining trends in the temperature regime if such trends exist.

Regional Board Staff Decision Recommendation:	This region was not assessed this cycle. All decisions have been carried over from the previous cycle and remain the same.

Line of Evidence (LOE) for Decision ID 74093, Temperature, water	Region 6
Amargosa River (Tecopa to Upper Canyon)

LOE ID:

25159

Pollutant:

Temperature, water

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

The U.S. Geological Survey sampled this station on March 17, 2004 and March 15 2005 under the Region 6 SWAMP program. Temperatures in two measurements were 20 and 20.5 degrees Celsius.

Data Reference:

2007. SWAMP Data for the Amargosa Hydrologic Unit

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The temperature objective in the Lahontan Basin Plan states: "The natural receiving water temperature of all waters shall not be altered unless it can be demonstrated to the satisfaction of the Regional Board that such an alteration in temperature does not adversely affect the water for beneficial uses.

For waters designated WARM, water temperature shall not be altered by more than five degrees Fahrenheit ... above or below the natural temperature. For waters designated COLD, the temperature shall not be altered.

Temperature objectives for COLD interstate waters and WARM interstate waters are as specified in the 'Water Quality Control Plan for Control of Temperature in The Coastal and Interstate Waters and Enclosed Bays and Estuaries of California' including any revisions."

Objective/Criterion Reference:

Water Quality Control Plan for the Lahontan Region (as amended)

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

One station, Amargosa River at Upper Canyon, was sampled.

Temporal Representation:

Two temperature measurements were taken on March 17, 2004 and March 15, 2005.

Environmental Conditions:

QAPP Information:

The data meet the quality assurance requirements of the SWAMP QAPP.

QAPP Information Reference(s):


DECISION ID	73683	Region 6
Amargosa River (Tecopa to Upper Canyon)

Pollutant:	Thallium
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2016)
Revision Status	Original
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Staff Conclusion:	Regional Board conclusion: This pollutant was considered for placement on the section 303(d) list in a previous assessment cycle. No new information was reviewed for this current assessment cycle. Therefore, the previous conclusion remains unchanged, and is as follows: 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. Three lines of evidence, consisting of one or two samples each, are available in the administrative record to assess this pollutant. There are no applicable saltwater aquatic life standards or criteria for thallium in inland saline waters. 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 satisfy the data quality requirements of section 6.1.4 of the Policy. 2. The sediment data used do not satisfy the data quantity requirements of section 6.1.5 of the Policy. 3. There are no applicable water quality standards or criteria and the data cannot be assessed using 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 Staff Decision Recommendation:	This region was not assessed this cycle. All decisions have been carried over from the previous cycle and remain the same.

Line of Evidence (LOE) for Decision ID 73683, Thallium	Region 6
Amargosa River (Tecopa to Upper Canyon)

LOE ID:

24999

Pollutant:

Thallium

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Inland Saline Water Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

The U.S. Geological Survey sampled this station on March 17, 2004 and March 15, 2005 under the Region 6 SWAMP program. Two samples for dissolved thallium were both below the detection level..

Data Reference:

2007. SWAMP Data for the Amargosa Hydrologic Unit

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

There are no applicable state or federal saltwater aquatic life standards or criteria for dissolved thallium in inland saline waters.

Objective/Criterion Reference:

Water Quality Control Plan for the Lahontan Region (as amended)

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

One station, Amargosa River at Upper Canyon, was sampled.

Temporal Representation:

Two samples were collected on March 17, 2004 and March 15, 2005.

Environmental Conditions:

QAPP Information:

The data meet the quality assurance requirements of the SWAMP QAPP.

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 73683, Thallium	Region 6
Amargosa River (Tecopa to Upper Canyon)

LOE ID:

24876

Pollutant:

Thallium

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

None

Beneficial Use:

Inland Saline Water Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Chemical monitoring of sediments

Data Used to Assess Water Quality:

Data Reference:

2007. SWAMP Data for the Amargosa Hydrologic Unit

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

There are no state or federal standards or criteria for thallium in sediment in inland saline waters.

Objective/Criterion Reference:

Water Quality Control Plan for the Lahontan Region (as amended)

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

One station, Amargosa River at Upper Canyon, was sampled.

Temporal Representation:

One sediment sample was collected on March 15, 2005.

Environmental Conditions:

QAPP Information:

The data meet the quality assurance requirements of the SWAMP QAPP.

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 73683, Thallium	Region 6
Amargosa River (Tecopa to Upper Canyon)

LOE ID:

24998

Pollutant:

Thallium

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Inland Saline Water Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

The U.S. Geological Survey sampled this station on March 17, 2004 and March 15, 2005 under the Region 6 SWAMP program. Two samples for total thallium were both below the detection level..

Data Reference:

2007. SWAMP Data for the Amargosa Hydrologic Unit

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

There are no applicable state or federal saltwater aquatic life standards or criteria for total thallium in inland saline waters.

Objective/Criterion Reference:

Water Quality Control Plan for the Lahontan Region (as amended)

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

One station, Amargosa River at Upper Canyon, was sampled.

Temporal Representation:

Two samples were collected on March 17, 2004 and March 15, 2005.

Environmental Conditions:

QAPP Information:

The data meet the quality assurance requirements of the SWAMP QAPP.

QAPP Information Reference(s):


DECISION ID	73139	Region 6
Amargosa River (Tecopa to Upper Canyon)

Pollutant:	Thorium
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2016)
Revision Status	Original
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Staff Conclusion:	Regional Board conclusion: This pollutant was considered for placement on the section 303(d) list in a previous assessment cycle. No new information was reviewed for this current assessment cycle. Therefore, the previous conclusion remains unchanged, and is as follows: 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, consisting of a single sediment sample, is available in the administrative record to assess this pollutant. There are no applicable water quality standards or criteria for thorium in the sediment of inland saline waters. 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 satisfy the data quality requirements of section 6.1.4 of the Policy. 2. The data used do not satisfy the data quantity requirements of section 6.1.5 of the Policy. 3. There are no applicable water quality standards or criteria and the single sample cannot be assessed using 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 Staff Decision Recommendation:	This region was not assessed this cycle. All decisions have been carried over from the previous cycle and remain the same.

Line of Evidence (LOE) for Decision ID 73139, Thorium	Region 6
Amargosa River (Tecopa to Upper Canyon)

LOE ID:

24877

Pollutant:

Thorium

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

None

Beneficial Use:

Inland Saline Water Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Chemical monitoring of sediments

Data Used to Assess Water Quality:

Data Reference:

2007. SWAMP Data for the Amargosa Hydrologic Unit

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

There are no state or federal standards or criteria for thorium in sediment in inland saline waters.

Objective/Criterion Reference:

Water Quality Control Plan for the Lahontan Region (as amended)

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

One station, Amargosa River at Upper Canyon, was sampled.

Temporal Representation:

One sediment sample was collected on March 15, 2005.

Environmental Conditions:

QAPP Information:

The data meet the quality assurance requirements of the SWAMP QAPP.

QAPP Information Reference(s):


DECISION ID	72935	Region 6
Amargosa River (Tecopa to Upper Canyon)

Pollutant:	Tin
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2016)
Revision Status	Original
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Staff Conclusion:	Regional Board conclusion: This pollutant was considered for placement on the section 303(d) list in a previous assessment cycle. No new information was reviewed for this current assessment cycle. Therefore, the previous conclusion remains unchanged, and is as follows: 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, consisting of a single sediment sample, is available in the administrative record to assess this pollutant. There are no applicable water quality standards or criteria for tin in the sediment of inland saline waters. 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 satisfy the data quality requirements of section 6.1.4 of the Policy. 2. The data used do not satisfy the data quantity requirements of section 6.1.5 of the Policy. 3. There are no applicable water quality standards or criteria and the single sample cannot be assessed using 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 Staff Decision Recommendation:	This region was not assessed this cycle. All decisions have been carried over from the previous cycle and remain the same.

Line of Evidence (LOE) for Decision ID 72935, Tin	Region 6
Amargosa River (Tecopa to Upper Canyon)

LOE ID:

24878

Pollutant:

Tin

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

None

Beneficial Use:

Inland Saline Water Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Chemical monitoring of sediments

Data Used to Assess Water Quality:

Data Reference:

2007. SWAMP Data for the Amargosa Hydrologic Unit

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

There are no state or federal standards or criteria for tin in sediment in inland saline waters.

Objective/Criterion Reference:

Water Quality Control Plan for the Lahontan Region (as amended)

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

One station, Amargosa River at Upper Canyon, was sampled.

Temporal Representation:

One sediment sample was collected on March 15, 2005.

Environmental Conditions:

QAPP Information:

The data meet the quality assurance requirements of the SWAMP QAPP.

QAPP Information Reference(s):


DECISION ID	72883	Region 6
Amargosa River (Tecopa to Upper Canyon)

Pollutant:	Titanium
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2016)
Revision Status	Original
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Staff Conclusion:	Regional Board conclusion: This pollutant was considered for placement on the section 303(d) list in a previous assessment cycle. No new information was reviewed for this current assessment cycle. Therefore, the previous conclusion remains unchanged, and is as follows: 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, consisting of a single sediment sample, is available in the administrative record to assess this pollutant. There are no applicable water quality standards or criteria for titanium in the sediment of inland saline waters. 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 satisfy the data quality requirements of section 6.1.4 of the Policy. 2. The data used do not satisfy the data quantity requirements of section 6.1.5 of the Policy. 3. There are no applicable water quality standards or criteria and the single sample cannot be assessed using 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 Staff Decision Recommendation:	This region was not assessed this cycle. All decisions have been carried over from the previous cycle and remain the same.

Line of Evidence (LOE) for Decision ID 72883, Titanium	Region 6
Amargosa River (Tecopa to Upper Canyon)

LOE ID:

24879

Pollutant:

Titanium

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

None

Beneficial Use:

Inland Saline Water Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Chemical monitoring of sediments

Data Used to Assess Water Quality:

Data Reference:

2007. SWAMP Data for the Amargosa Hydrologic Unit

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

There are no state or federal standards or criteria for titanium in sediment in inland saline waters.

Objective/Criterion Reference:

Water Quality Control Plan for the Lahontan Region (as amended)

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

One station, Amargosa River at Upper Canyon, was sampled.

Temporal Representation:

One sediment sample was collected on March 15, 2005.

Environmental Conditions:

QAPP Information:

The data meet the quality assurance requirements of the SWAMP QAPP.

QAPP Information Reference(s):


DECISION ID	72742	Region 6
Amargosa River (Tecopa to Upper Canyon)

Pollutant:	Total Dissolved Solids
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2016)
Revision Status	Original
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Staff Conclusion:	Regional Board conclusion: This pollutant was considered for placement on the section 303(d) list in a previous assessment cycle. No new information was reviewed for this current assessment cycle. Therefore, the previous conclusion remains unchanged, and is as follows: 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, consisting of two samples expressed as TDS and one sample expressed as "Residue", is available in the administrative record to assess this pollutant. There are no applicable water quality standards or criteria for total dissolved solids in inland saline waters. 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 satisfy the data quality requirements of section 6.1.4 of the Policy. 2. The data used do not satisfy the data quantity requirements of section 6.1.5 of the Policy. 3. There are no applicable water quality standards or criteria and the data cannot be assessed using 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 Staff Decision Recommendation:	This region was not assessed this cycle. All decisions have been carried over from the previous cycle and remain the same.

Line of Evidence (LOE) for Decision ID 72742, Total Dissolved Solids	Region 6
Amargosa River (Tecopa to Upper Canyon)

LOE ID:

25176

Pollutant:

Total Dissolved Solids

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total Dissolved

Beneficial Use:

Inland Saline Water Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

The U.S. Geological Survey sampled this station on March 17, 2004 and March 15, 2005 under the Region 6 SWAMP program. Two samples had TDS concentrations of 2640 and 2210 mg/L. Another sample was reported as "residue" (the sum of constituents); itsconcentration was 2180 mg/L.

Data Reference:

2007. SWAMP Data for the Amargosa Hydrologic Unit

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

There are no state or federal saltwater aquatic life standards or criteria for total dissolved solids (TDS) in inland saline waters.

Objective/Criterion Reference:

Water Quality Control Plan for the Lahontan Region (as amended)

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

One station, Amargosa River at Upper Canyon, was sampled.

Temporal Representation:

Three samples were taken on March 17, 2004 and March 15, 2005.

Environmental Conditions:

QAPP Information:

The data meet the quality assurance requirements of the SWAMP QAPP.

QAPP Information Reference(s):


DECISION ID	72607	Region 6
Amargosa River (Tecopa to Upper Canyon)

Pollutant:	Total Kjeldahl Nitrogen (TKN)
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2016)
Revision Status	Original
Impairment from Pollutant or Pollution:	Pollution

Regional Board Staff Conclusion:	Regional Board conclusion: This pollutant was considered for placement on the section 303(d) list in a previous assessment cycle. No new information was reviewed for this current assessment cycle. Therefore, the previous conclusion remains unchanged, and is as follows: 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 biological data are available for assessment whether the chemical data exceed the water quality objective for biostimulatory substances. 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 satisfy the data quality requirements of section 6.1.4 of the Policy. 2. The data used do not satisfy the data quantity requirements of section 6.1.5 of the Policy. Only one sample per year was collected. 3. No biological data are available for assessment of compliance with the objective and the data cannot be assessed using 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 Staff Decision Recommendation:	This region was not assessed this cycle. All decisions have been carried over from the previous cycle and remain the same.

Line of Evidence (LOE) for Decision ID 72607, Total Kjeldahl Nitrogen (TKN)	Region 6
Amargosa River (Tecopa to Upper Canyon)

LOE ID:

25177

Pollutant:

Total Kjeldahl Nitrogen (TKN)

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Inland Saline Water Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

The U.S. Geological Survey sampled this station on March 17, 2004 and March 15, 2005 under the Region 6 SWAMP program. Two samples had TKN concentrations of 0.63 and 0.36 mg/L.

Data Reference:

2007. SWAMP Data for the Amargosa Hydrologic Unit

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

There are no applicable state or federal saltwater aquatic life standards or criteria for total Kjeldahl nitrogen (TKN). The Lahontan Basin Plan's regionwide objective for biostimulatory substances states: "Waters shall not contain biostimulatory substances in concentrations that promote aquatic growths to the extent that such growths cause nuisance or adversely affect the water for beneficial uses."

Objective/Criterion Reference:

Water Quality Control Plan for the Lahontan Region (as amended)

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

One station, Amargosa River at Upper Canyon, was sampled.

Temporal Representation:

Two samples were taken on March 17, 2004 and March 15, 2005.

Environmental Conditions:

QAPP Information:

The data meet the quality assurance requirements of the SWAMP QAPP.

QAPP Information Reference(s):


DECISION ID	70745	Region 6
Amargosa River (Tecopa to Upper Canyon)

Pollutant:	Triclopyr
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2016)
Revision Status	Original
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Staff Conclusion:	Regional Board conclusion: This pollutant was considered for placement on the section 303(d) list in a previous assessment cycle. No new information was reviewed for this current assessment cycle. Therefore, the previous conclusion remains unchanged, and is as follows: 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. The single sample shows detectable triclopyr and therefore exceeds 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 satisfy the data quality requirements of section 6.1.4 of the Policy. 2. The data used do not satisfy the data quantity requirements of section 6.1.5 of the Policy. 3. The single sample exceeded the water quality objective and this does not exceed the allowable frequency listed in Table 3.1 of the Listing Policy. The minimum sample number requirements of Table 3.1 are not met. 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 Staff Decision Recommendation:	This region was not assessed this cycle. All decisions have been carried over from the previous cycle and remain the same.

Line of Evidence (LOE) for Decision ID 70745, Triclopyr	Region 6
Amargosa River (Tecopa to Upper Canyon)

LOE ID:

27049

Pollutant:

Triclopyr

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Inland Saline Water Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

The U.S. Geological Survey sampled this station on March 17, 2004 under the Region 6 SWAMP program. The single sample had a detectable triclopyr concentration of 0.07 ug/L.

Data Reference:

2007. SWAMP Data for the Amargosa Hydrologic Unit

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

There are no state or federal saltwater aquatic life standards or criteria for the herbicide triclopyr in inland saline waters. The Lahontan Basin Plan's narrative objective for pesticides provides that:
"Pesticide concentrations, individually or collectively, shall not exceed the lowest detectable levels, using the most recent detection procedures available."

Objective/Criterion Reference:

Water Quality Control Plan for the Lahontan Region (as amended)

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

One station, Amargosa River at Upper Canyon, was sampled.

Temporal Representation:

One sample was collected on March 17, 2004.

Environmental Conditions:

QAPP Information:

The data meet the quality assurance requirements of the SWAMP QAPP.

QAPP Information Reference(s):


DECISION ID	75544	Region 6
Amargosa River (Tecopa to Upper Canyon)

Pollutant:	Tritium
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2016)
Revision Status	Original
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Staff Conclusion:	Regional Board conclusion: This pollutant was considered for placement on the section 303(d) list in a previous assessment cycle. No new information was reviewed for this current assessment cycle. Therefore, the previous conclusion remains unchanged, and is as follows: 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 biological data are available for assessment whether either of the samples exceeds the narrative 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 satisfy the data quality requirements of section 6.1.4 of the Policy. 2. The data used do not satisfy the data quantity requirements of section 6.1.5 of the Policy. 3. No biological data are available to evaluate compliance with the objective and the data cannot be assessed using 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 Staff Decision Recommendation:	This region was not assessed this cycle. All decisions have been carried over from the previous cycle and remain the same.

Line of Evidence (LOE) for Decision ID 75544, Tritium	Region 6
Amargosa River (Tecopa to Upper Canyon)

LOE ID:

27062

Pollutant:

Tritium

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Inland Saline Water Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

The U.S. Geological Survey sampled this station on March 17, 2004 and March 15, 2005 under the Region 6 SWAMP program. Two samples had tritium levels of 0.8 and 1.1 pCi/L. The tritium 2 sigma combined uncertainties were 0.58 and 0.58 pCi/L. No biological data are available for assessment of compliance with the narrative water quality objective.

Data Reference:

2007. SWAMP Data for the Amargosa Hydrologic Unit

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

There are no specific state or federal saltwater aquatic life standards or criteria for tritium in inland saline waters. The Lahontan Basin Plan's narrative water quality objective for radioactivity provides that: "Radionuclides shall not be present in concentrations which are deleterious to human, plant, animal, or aquatic life nor which result in the accumulation of radionuclides in the food web to an extent which presents a hazard to human, plant, animal or aquatic life." The objective also incorporates California Maximum Contaminant Levels (MUN) for radioactivity for waters designated for the MUN use. The MCLs do not apply to the Amargosa River.

Objective/Criterion Reference:

Water Quality Control Plan for the Lahontan Region (as amended)

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

One station, Amargosa River at Upper Canyon, was sampled.

Temporal Representation:

Two samples were collected on March 17, 2004 and March 15, 2005.

Environmental Conditions:

QAPP Information:

The data meet the quality assurance requirements of the SWAMP QAPP.

QAPP Information Reference(s):


DECISION ID	75490	Region 6
Amargosa River (Tecopa to Upper Canyon)

Pollutant:	Turbidity
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2016)
Revision Status	Original
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Staff Conclusion:	Regional Board conclusion: This pollutant was considered for placement on the section 303(d) list in a previous assessment cycle. No new information was reviewed for this current assessment cycle. Therefore, the previous conclusion remains unchanged, and is as follows: Two lines of evidence are available in the administrative record to assess this pollutant. The narrative water quality objective for turbidity is an antidegradation-based objective and the two available samples are insufficient to document baseline and trend conditions as required under Listing Policy Section 3.10. Both samples are reported as NTU but one may actually be for NTRU. If this is the case the two samples are not comparable. 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 satisfy the data quality requirements of section 6.1.4 of the Policy. 2. The data used do not satisfy the data quantity requirements of section 6.1.5 of the Policy. Samples were collected only once a year. 3. The requirements of Listing Policy section 3.10 to document baseline and trend conditions are not met in relation to the narrative water quality objective. 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 Staff Decision Recommendation:	This region was not assessed this cycle. All decisions have been carried over from the previous cycle and remain the same.

Line of Evidence (LOE) for Decision ID 75490, Turbidity	Region 6
Amargosa River (Tecopa to Upper Canyon)

LOE ID:

25155

Pollutant:

Turbidity

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Inland Saline Water Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

The U.S. Geological Survey sampled this station on March 17, 2004 under the Region 6 SWAMP program. Turbidity values in one measurement was 12 NTU. (Note: a second turbidity measurement from 2005 was reported as NTU but includes the method number associated with NTRU in data for a different Amargosa River station.)

Data Reference:

2007. SWAMP Data for the Amargosa Hydrologic Unit

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The regionwide turbidity objective in the Lahontan Basin Plan states: "Waters shall be free of changes in turbidity that cause nuisance or adversely affect the water for beneficial uses. Increases in turbidity shall not exceed natural levels by more than 10 percent."

Objective/Criterion Reference:

Water Quality Control Plan for the Lahontan Region (as amended)

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

One station, Amargosa River at Upper Canyon, was sampled.

Temporal Representation:

One turbidity measurement expressed as NTU was taken on March 17, 2004.

Environmental Conditions:

QAPP Information:

The data meet the quality assurance requirements of the SWAMP QAPP.

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 75490, Turbidity	Region 6
Amargosa River (Tecopa to Upper Canyon)

LOE ID:

27155

Pollutant:

Turbidity

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Inland Saline Water Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

The U.S. Geological Survey sampled this station on March 15, 2005 under the Region 6 SWAMP program. Turbidity in one measurement was reported as 6.4 NTU. The USGS has recently begun measuring turbidity as NTRU, using equipment different than that used for NTU. The 2005 measurement has the same method number as a March 2005 NTRU measurement for a different Amargosa River station and should probably be interpreted as NTRU.

Data Reference:

2007. SWAMP Data for the Amargosa Hydrologic Unit

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan for the Lahontan Region (as amended)

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

One station, Amargosa River at Upper Canyon, was sampled.

Temporal Representation:

One turbidity measurement expressed as NTU (but probably for NTRU) was taken on March 15, 2005.

Environmental Conditions:

QAPP Information:

The data meet the quality assurance requirements of the SWAMP QAPP.

QAPP Information Reference(s):


DECISION ID	75031	Region 6
Amargosa River (Tecopa to Upper Canyon)

Pollutant:	Uranium
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2016)
Revision Status	Original
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Staff Conclusion:	Regional Board conclusion: This pollutant was considered for placement on the section 303(d) list in a previous assessment cycle. No new information was reviewed for this current assessment cycle. Therefore, the previous conclusion remains unchanged, and is as follows: 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. There are no applicable water quality standards or criteria for this pollutant in sediment of inland saline waters. 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 satisfy the data quality requirements of section 6.1.4 of the Policy. 2. The data used (only one sample) do not satisfy the data quantity requirements of section 6.1.5 of the Policy. 3. There are no applicable water quality standards or criteria and the minimum sample number requirements of Table 3.1 of the Listing Policy are not met. 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 Staff Decision Recommendation:	This region was not assessed this cycle. All decisions have been carried over from the previous cycle and remain the same.

Line of Evidence (LOE) for Decision ID 75031, Uranium	Region 6
Amargosa River (Tecopa to Upper Canyon)

LOE ID:

24884

Pollutant:

Uranium

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

None

Beneficial Use:

Inland Saline Water Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Chemical monitoring of sediments

Data Used to Assess Water Quality:

Data Reference:

2007. SWAMP Data for the Amargosa Hydrologic Unit

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

There are no state or federal standards or criteria for uranium in sediment in inland saline waters.

Objective/Criterion Reference:

Water Quality Control Plan for the Lahontan Region (as amended)

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

One station, Amargosa River at Upper Canyon, was sampled.

Temporal Representation:

One sediment sample was collected on March 15, 2005.

Environmental Conditions:

QAPP Information:

The data meet the quality assurance requirements of the SWAMP QAPP.

QAPP Information Reference(s):


DECISION ID	75902	Region 6
Amargosa River (Tecopa to Upper Canyon)

Pollutant:	Vanadium
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2016)
Revision Status	Original
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Staff Conclusion:	Regional Board conclusion: This pollutant was considered for placement on the section 303(d) list in a previous assessment cycle. No new information was reviewed for this current assessment cycle. Therefore, the previous conclusion remains unchanged, and is as follows: 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. Three lines of evidence, consisting of one or two samples each, are available in the administrative record to assess this pollutant. There are no applicable saltwater aquatic life standards or criteria for vanadium in inland saline waters. 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 satisfy the data quality requirements of section 6.1.4 of the Policy. 2. The sediment data used do not satisfy the data quantity requirements of section 6.1.5 of the Policy. 3. There are no applicable water quality standards or criteria and the data cannot be assessed using 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 Staff Decision Recommendation:	This region was not assessed this cycle. All decisions have been carried over from the previous cycle and remain the same.

Line of Evidence (LOE) for Decision ID 75902, Vanadium	Region 6
Amargosa River (Tecopa to Upper Canyon)

LOE ID:

24880

Pollutant:

Vanadium

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

None

Beneficial Use:

Inland Saline Water Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Chemical monitoring of sediments

Data Used to Assess Water Quality:

Data Reference:

2007. SWAMP Data for the Amargosa Hydrologic Unit

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

There are no state or federal standards or criteria for vanadium in sediment in inland saline waters.

Objective/Criterion Reference:

Water Quality Control Plan for the Lahontan Region (as amended)

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

One station, Amargosa River at Upper Canyon, was sampled.

Temporal Representation:

One sediment sample was collected on March 15, 2005.

Environmental Conditions:

QAPP Information:

The data meet the quality assurance requirements of the SWAMP QAPP.

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 75902, Vanadium	Region 6
Amargosa River (Tecopa to Upper Canyon)

LOE ID:

25040

Pollutant:

Vanadium

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Inland Saline Water Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

The U.S. Geological Survey sampled this station on March 17, 2004 and March 15, 2005 under the Region 6 SWAMP program. Two samples had dissolved vanadium concentrations of 13.2 and 14.2 ug/L.

Data Reference:

2007. SWAMP Data for the Amargosa Hydrologic Unit

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

There are no applicable state or federal saltwater aquatic life standards or criteria for dissolved vanadium in inland saline waters.

Objective/Criterion Reference:

Water Quality Control Plan for the Lahontan Region (as amended)

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

One station, Amargosa River at Upper Canyon, was sampled.

Temporal Representation:

Two samples were collected on March 17, 2004 and March 15, 2005.

Environmental Conditions:

QAPP Information:

The data meet the quality assurance requirements of the SWAMP QAPP.

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 75902, Vanadium	Region 6
Amargosa River (Tecopa to Upper Canyon)

LOE ID:

25006

Pollutant:

Vanadium

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Inland Saline Water Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

The U.S. Geological Survey sampled this station on March 17, 2004 and March 15, 2005 under the Region 6 SWAMP program. Two samples had total vanadium concentrations of 10 and 6 ug/L.

Data Reference:

2007. SWAMP Data for the Amargosa Hydrologic Unit

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

There are no applicable state or federal saltwater aquatic life standards or criteria for total vanadium in inland saline waters.

Objective/Criterion Reference:

Water Quality Control Plan for the Lahontan Region (as amended)

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

One station, Amargosa River at Upper Canyon, was sampled.

Temporal Representation:

Two samples were collected on March 17, 2004 and March 15, 2005.

Environmental Conditions:

QAPP Information:

The data meet the quality assurance requirements of the SWAMP QAPP.

QAPP Information Reference(s):


DECISION ID	73196	Region 6
Amargosa River (Tecopa to Upper Canyon)

Pollutant:	Ytterbium
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2016)
Revision Status	Original
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Staff Conclusion:	Regional Board conclusion: This pollutant was considered for placement on the section 303(d) list in a previous assessment cycle. No new information was reviewed for this current assessment cycle. Therefore, the previous conclusion remains unchanged, and is as follows: 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, consisting of a single sediment sample, is available in the administrative record to assess this pollutant. There are no applicable water quality standards or criteria for ytterbium in the sediment of inland saline waters. 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 satisfy the data quality requirements of section 6.1.4 of the Policy. 2. The data used do not satisfy the data quantity requirements of section 6.1.5 of the Policy. 3. There are no applicable water quality standards or criteria and the single sample cannot be assessed using 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 Staff Decision Recommendation:	This region was not assessed this cycle. All decisions have been carried over from the previous cycle and remain the same.

Line of Evidence (LOE) for Decision ID 73196, Ytterbium	Region 6
Amargosa River (Tecopa to Upper Canyon)

LOE ID:

24881

Pollutant:

Ytterbium

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

None

Beneficial Use:

Inland Saline Water Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Chemical monitoring of sediments

Data Used to Assess Water Quality:

Data Reference:

2007. SWAMP Data for the Amargosa Hydrologic Unit

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

There are no state or federal standards or criteria for ytterbium in sediment in inland saline waters.

Objective/Criterion Reference:

Water Quality Control Plan for the Lahontan Region (as amended)

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

One station, Amargosa River at Upper Canyon, was sampled.

Temporal Representation:

One sediment sample was collected on March 15, 2005.

Environmental Conditions:

QAPP Information:

The data meet the quality assurance requirements of the SWAMP QAPP.

QAPP Information Reference(s):


DECISION ID	73059	Region 6
Amargosa River (Tecopa to Upper Canyon)

Pollutant:	Yttrium
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2016)
Revision Status	Original
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Staff Conclusion:	Regional Board conclusion: This pollutant was considered for placement on the section 303(d) list in a previous assessment cycle. No new information was reviewed for this current assessment cycle. Therefore, the previous conclusion remains unchanged, and is as follows: 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, consisting of a single sediment sample, is available in the administrative record to assess this pollutant. There are no applicable water quality standards or criteria for yttrium in the sediment of inland saline waters. 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 satisfy the data quality requirements of section 6.1.4 of the Policy. 2. The data used do not satisfy the data quantity requirements of section 6.1.5 of the Policy. 3. There are no applicable water quality standards or criteria and the single sample cannot be assessed using 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 Staff Decision Recommendation:	This region was not assessed this cycle. All decisions have been carried over from the previous cycle and remain the same.

Line of Evidence (LOE) for Decision ID 73059, Yttrium	Region 6
Amargosa River (Tecopa to Upper Canyon)

LOE ID:

24882

Pollutant:

Yttrium

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

None

Beneficial Use:

Inland Saline Water Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Chemical monitoring of sediments

Data Used to Assess Water Quality:

Data Reference:

2007. SWAMP Data for the Amargosa Hydrologic Unit

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

There are no state or federal standards or criteria for yttrium in sediment in inland saline waters.

Objective/Criterion Reference:

Water Quality Control Plan for the Lahontan Region (as amended)

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

One station, Amargosa River at Upper Canyon, was sampled.

Temporal Representation:

One sediment sample was collected on March 15, 2005.

Environmental Conditions:

QAPP Information:

The data meet the quality assurance requirements of the SWAMP QAPP.

QAPP Information Reference(s):


DECISION ID	74211	Region 6
Amargosa River (Tecopa to Upper Canyon)

Pollutant:	Zinc
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2016)
Revision Status	Original
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Staff Conclusion:	Regional Board conclusion: This pollutant was considered for placement on the section 303(d) list in a previous assessment cycle. No new information was reviewed for this current assessment cycle. Therefore, the previous conclusion remains unchanged, and is as follows: 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. Three lines of evidence, consisting of one or two samples each, are available in the administrative record to assess this pollutant. There are no applicable saltwater aquatic life standards or criteria for zinc in inland saline waters. The California Toxic Rule standards and a sediment criterion were not exceeded. Both are based on toxicity to marine/estuarine organisms. 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 satisfy the data quality requirements of section 6.1.4 of the Policy. 2. The sediment data used do not satisfy the data quantity requirements of section 6.1.5 of the Policy. 3. There are no applicable water quality standards or criteria for zinc in inland saline waters. The California Toxics Rule standards and sediment criterion were not exceeded and this does not exceed the allowable frequency in Listing Policy Table 3.1. However, the single sediment sample does not meet the minimum sample number requirements 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 Staff Decision Recommendation:	This region was not assessed this cycle. All decisions have been carried over from the previous cycle and remain the same.

Line of Evidence (LOE) for Decision ID 74211, Zinc	Region 6
Amargosa River (Tecopa to Upper Canyon)

LOE ID:

25041

Pollutant:

Zinc

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Inland Saline Water Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

The U.S. Geological Survey sampled this station on March 17, 2004 and March 15, 2005 under the Region 6 SWAMP program. Two samples had dissolved zinc concentrations of 1.8 and 2.2 ug/L.

Data Reference:

2007. SWAMP Data for the Amargosa Hydrologic Unit

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The California Toxics Rule standards for dissolved zinc include an acute toxicity limit of 90 ug/L and a chronic toxicity limit of 81 ug/L.

Objective/Criterion Reference:

Water Quality Control Plan for the Lahontan Region (as amended)

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

One station, Amargosa River at Upper Canyon, was sampled.

Temporal Representation:

Two samples were collected on March 17, 2004 and March 15, 2005.

Environmental Conditions:

QAPP Information:

The data meet the quality assurance requirements of the SWAMP QAPP.

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 74211, Zinc	Region 6
Amargosa River (Tecopa to Upper Canyon)

LOE ID:

25042

Pollutant:

Zinc

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Inland Saline Water Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

The U.S. Geological Survey sampled this station on March 17, 2004 and March 15, 2005 under the Region 6 SWAMP program. The concentrations of total zinc in 2 samples were both estimated values.

Data Reference:

2007. SWAMP Data for the Amargosa Hydrologic Unit

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

There are no applicable state or federal saltwater aquatic life standards or criteria for total zinc in inland surface waters.

Objective/Criterion Reference:

Water Quality Control Plan for the Lahontan Region (as amended)

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

One station, Amargosa River at Upper Canyon, was sampled.

Temporal Representation:

Two samples were collected on March 17, 2004 and March 15, 2005.

Environmental Conditions:

QAPP Information:

The data meet the quality assurance requirements of the SWAMP QAPP.

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 74211, Zinc	Region 6
Amargosa River (Tecopa to Upper Canyon)

LOE ID:

24887

Pollutant:

Zinc

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

None

Beneficial Use:

Inland Saline Water Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Chemical monitoring of sediments

Data Used to Assess Water Quality:

Data Reference:

2007. SWAMP Data for the Amargosa Hydrologic Unit

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

There are no state or federal standards or criteria for zinc in sediment in inland saline waters. The Effects Range-Median for zinc in marine and estuarine sediments is 410 ug/g dry weight; see Long et al. (1995).

Objective/Criterion Reference:

Incidence of adverse biological effects within ranges of chemical concentrations in marine and estuary sediments. Environmental Management. 19, (1): 81-97

Water Quality Control Plan for the Lahontan Region (as amended)

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

One station, Amargosa River at Upper Canyon, was sampled.

Temporal Representation:

One sediment sample was collected on March 15, 2005.

Environmental Conditions:

QAPP Information:

The data meet the quality assurance requirements of the SWAMP QAPP.

QAPP Information Reference(s):


DECISION ID	73645	Region 6
Amargosa River (Tecopa to Upper Canyon)

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)(2016)
Revision Status	Original
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Staff Conclusion:	Regional Board conclusion: This pollutant was considered for placement on the section 303(d) list in a previous assessment cycle. No new information was reviewed for this current assessment cycle. Therefore, the previous conclusion remains unchanged, and is as follows: The Lahontan Basin Plan's narrative pH objective is an antidegradation-based objective that requires that there be no change greater than 0.5 pH units in waters designated for the Cold Freshwater Habitat (COLD) or Warm Freshwater Habitat (WARM) beneficial uses. (A pH range of 6.5 to 8.5 units applies to "all other waters.") Listing Policy Section 3.10 contains directions for assessment based on trends in water quality. These directions include requirements to establish specific baseline conditions and specify the influence of seasonal and interannual effects. One line of evidence, consisting of only two annual samples, is available to support this decision. There are not enough pH samples to establish baseline conditions (including diel, seasonal, annual and interannual variations) or to detect changes in the pH regime due to controllable factors, if such trends exist.

Regional Board Staff Decision Recommendation:	This region was not assessed this cycle. All decisions have been carried over from the previous cycle and remain the same.

Line of Evidence (LOE) for Decision ID 73645, pH	Region 6
Amargosa River (Tecopa to Upper Canyon)

LOE ID:

25158

Pollutant:

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

The U.S. Geological Survey sampled this station on March 17, 2004 and March 15, 2005 under the Region 6 SWAMP program. In two measurements, pH was 8.6 and 8.7 units.

Data Reference:

2007. SWAMP Data for the Amargosa Hydrologic Unit

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

.The Lahontan Basin Plan's objective for pH states: "In fresh waters with designated beneficial uses of COLD or WARM, changes in normal ambient pH levels shall not exceed 0.5 pH units. For all other waters of the region, the pH shall not be depressed below 6.5 nor raised above 8.5 units.

The Regional Board recognizes that some waters of the Region may have natural pH levels outside of the 6.5 to 8.5 range. Compliance with the pH objective for these waters will be determined on a case-by-case basis."

Objective/Criterion Reference:

Water Quality Control Plan for the Lahontan Region (as amended)

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

One station, Amargosa River at Upper Canyon, was sampled.

Temporal Representation:

Two pH measurements were taken on March 17, 2004 and March 15, 2005.

Environmental Conditions:

QAPP Information:

The data meet the quality assurance requirements of the SWAMP QAPP.

QAPP Information Reference(s):