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

Supporting Information

Regional Board 6 - Lahontan Region

Water Body Name:	Keough Hot Springs
Water Body ID:	CAW6032018319990129104958
Water Body Type:	Wetland, Freshwater


DECISION ID	76689	Region 6
Keough Hot Springs

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:	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. Four of the datapoints exceed the water quality objective. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the section 303(d) list in the Water Quality Limited Segments category. This conclusion is based on the staff findings that: 1. The data used 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 collected monthly or twice monthly do not capture diel and day to day variations in dissolved oxygen concentrations. 3. Four out of 203 datapoints exceeded the water quality objective 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:	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 76689, Oxygen, Dissolved	Region 6
Keough Hot Springs

LOE ID:

28012

Pollutant:

Oxygen, Dissolved

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

203

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical monitoring (conventional pollutants only)

Data Used to Assess Water Quality:

The Owens Valley Indian Water Commission submitted data for Keough Hot Ditch during the 2006-2007 solicitation process. Dissolved oxygen concentrations were measured approximately twice monthly in 2000 and approximately monthly from 2001 to early 2007 For 2000 through 2003, results were reported as low and high concentrations for the same sample, with a few samples reported as average values. For 2004 through 2007, only average concentrations were reported. Including averages of the high and low concentrations reported in the early years, the lowest average dissolved oxygen concentration was ____mg/L for _____, 2003, and the highest average concentration was ____ for ____2000. Four average datapoints for _____ 2003 were below the 3.0 mg/L minimum concentration allowed by the water quality objective.

Data Reference:

2007. Data for Keough Hot Ditch

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The water quality objective (Lahontan Basin Plan Table 3-6) is a 1-ay minimum dissolved oxygen concentration of 3.0 mg/L to protect the Warm Freshwater Habitat beneficial use. (Although the springs are designated for both the WARM and COLD uses, measured temperatures are consistently above ___ degrees Fahrenheit and the WARM use is more appropriate to assess dissolved oxygen conditions for indigenous aquatic life.)

Objective/Criterion Reference:

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

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Two pools on Keough Hot Ditch (called "Upper" and "Lower" in the data) were sampled.

Temporal Representation:

Samples were collected at each station approximately twice monthly in 2000 and approximately monthly between 2001 and early 2007.

Environmental Conditions:

Due to difficulties in georeferencing, this LOE has been prepared for "Keough Hot Springs." The Owens Valley Indian Water Commission monitored "Keough Hot Ditch" downstream from the source springs and and swimming pool discharge.

The Keough Hot Springs are natural geothermal springs with temperatures over 120 degrees F. Part of the flow from the springs is directed to a swimming pool at a resort. When the resort is open, the operator uses a cooling system for water supplied to the pool. Water released from the swimming pool blends with the remainder of the outflow from the springs that has been piped around the resort and enters a ditch with a series of pools. The hot ditch is used for public recreation, and the springs and ditch are culturally important to Native Americans.

Keough Hot Springs is designated for the both the Warm Freshwater Habitat and Cold Freshwater Habitat beneficial uses. No data on aquatic life in the springs and their outflow are available. The previously designated (but not existing) Municipal and Domestic Supply beneficial use was removed through Basin Plan amendments effective in 2002.

QAPP Information:

The data submittal included descriptions of the instruments used and noted that calibration records are available on request.

QAPP Information Reference(s):


DECISION ID	76274	Region 6
Keough Hot Springs

Pollutant:	Salinity
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:	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 satisfy the data quantity requirements of section 6.1.5 of the Policy. 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 76274, Salinity	Region 6
Keough Hot Springs

LOE ID:

28011

Pollutant:

Salinity

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

197

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical monitoring (conventional pollutants only)

Data Used to Assess Water Quality:

The Owens Valley Indian Water Commission submitted salinity data for Keough Hot Ditch during the 2006-2007 solicitation process. Salinity was measured approxmately twice monthly in 2000 and approximately monthly between 2001 and early 2007. Results reported as "percent salinity," for 2000 to mid-2004 ranged from 0.03 to 0.05 percent. Results reported as parts per thousand (ppt) from mid 2004 to early 2007 ranged from 0.39 to 0.43 ppt. In oceanographic terms water with salinity less than 0.05 percent or less than 0.5 ppt is considered fresh.

Data Reference:

2007. Data for Keough Hot Ditch

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

There are no state or federal standards or criteria for salinity for the protection of the Warm Freshwater Habitat beneficial use.

Objective/Criterion Reference:

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

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Two pools on Keough Hot Ditch (called "Upper" and "Lower" in the data) were sampled.

Temporal Representation:

Samples were collected at each station approximately twic monthly in 2000 and approximately monthly between 2000 and early 2007.

Environmental Conditions:

QAPP Information:

The data submittal included descriptions of the instruments used and noted that calibration records are available on request.

QAPP Information Reference(s):


DECISION ID	72793	Region 6
Keough Hot Springs

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:	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 satisfy the data quantity requirements of section 6.1.5 of the Policy. 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 72793, Specific Conductance	Region 6
Keough Hot Springs

LOE ID:

28010

Pollutant:

Specific Conductance

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

187

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical monitoring (conventional pollutants only)

Data Used to Assess Water Quality:

The Owens Valley Indian Water Commission submitted data for Keough Hot Ditch during the 2006-2007 solicitation process. Specific conductance was measured approximately twice a month in 2000 and approximately monthly between 2001 and early 2007. Specific conductance in 187 measurements ranged from 0.810 to 1.07 millisiemens per centimeter (mS/cm). Between 2005 and 2007, 50 duplicate samples were taken, ranging from 0.967 to 0.1014 mS/cm. Naturally high specific conductance is expected in geothermal waters of the Lahontan Region.

Data Reference:

2007. Data for Keough Hot Ditch

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

There are no state or federal standards or criteria for specific conductance for the protection of the Warm Freshwater Habitat beneficial use.

Objective/Criterion Reference:

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

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Two pools on Keough Hot Ditch (called "Upper" and "Lower" in the data) were sampled.

Temporal Representation:

Measurements were taken at each station approximately twice monthly in 2000 and approximately monthly between 2001 and early 2007.

Environmental Conditions:

QAPP Information:

The data submittal included descriptions of the instruments used and noted that calibration records are available on request.

QAPP Information Reference(s):


DECISION ID	76092	Region 6
Keough Hot Springs

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:	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 (LOEs) are available in the administrative record to assess this pollutant. These LOEs are not directly comparable because samples were taken at different locations and one of the datasets was collected after the implementation of management measures meant to increase the temperature of Keough Hot Ditch. Eleven sets of temperature samples by the Owens Valley Indian Water Commission showed that temperatures in two pools the ditch were more than 5 degrees Fahrenheit lower when the resort cooling system was operating than in previous samples taken when it was not operating. Twenty-six sets of temperature measurements taken by the resort operator showed that the temperature of the swimming pool outflow is generally lower than the temperature at the resort's property line, after the outflow mixes with hot water piped from the source springs, and after the mixed water is exposed to ambient air temperatures. The resort operator has not yet submitted all of the information requested by the Water Board's regulatory staff. Section 303(d) listing is not recommended at this time because more information and data are needed to evaluate the impacts of the resort cooling system operation on temperatures in Keough Hot Ditch.

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 76092, Temperature, water	Region 6
Keough Hot Springs

LOE ID:

28262

Pollutant:

Temperature, water

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Water Contact Recreation

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical monitoring (conventional pollutants only)

Data Used to Assess Water Quality:

The operator of the Keough's Hot Springs resort, Brown's Supply, Inc., measured temperature at each of four stations 14 times between October 2007 and April 2008. Temperature was measured at each of five stations 12 times between December 2008 and February 2009.

The ranges of temperatures were as follows. The first set of numbers is for October 2007 through April 2008; the second set is for December 2008 through February 2009.

For the piped discharge from the source springs, 113 to 122 degrees F and 104 to 118.5 degrees F.

For the swimming pool outflow, temperatures were 85 to 91. 5 degrees F and 83 to 88 degrees F.

For a "mix" station below the confluence of the source and swimming pool discharges, temperatures were 89.5 to 112.5 degrees F. (Temperature was measured only from December 2008 to February 2009.)

For a "flume" station below the "mix" station and above the property line, temperatures were 97.5 to 112 degrees F and 89.5 to 97.5 degrees F.

For the "property line" station, temperatures were 93.5 to 102 degrees F and 81 to 97/5 degrees F.

Except for one sample, temperatures were higher at the "property line" station than in the swimming pool outflow.

Data Reference:

2009. Temperature data for stations at Keough's Hot Springs Resort

SWAMP Data:

Non-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:

Temperature was measured in the swimming pool outflow, in the piped discharge from the source springs, at a "flume" station downstream of the junction of the pool discharge and source spring discharge, and at the "property line" of the resort. Between December 2008 and February 2009, temperature was also measured at a "mix" station below the junction of the pool and source discharges and above the "flume" station.

Temporal Representation:

. The operator of the Keough's Hot Springs resort, Brown's Supply, Inc., measured temperature at each of four stations 14 times between October 2007 and April 2008. Temperature was measured at each of five stations 12 times between December 2008 and February 2009.

Environmental Conditions:

Due to difficulties in georeferencing, this LOE has been prepared for "Keough Hot Springs." The Keough Hot Springs are natural geothermal springs with temperatures over 120 degrees F. Part of the flow from the springs is directed to a swimming pool at a resort. When the resort is open, the operator uses a cooling system for water supplied to the pool. Water released from the swimming pool blends with the remainder of the outflow from the springs that has been piped around the resort and enters a ditch with a series of pools. The hot ditch is used for public recreation, and the springs and ditch are culturally important to Native Americans.

Keough Hot Springs is designated for the both the Warm Freshwater Habitat and Cold Freshwater Habitat beneficial uses. No data on aquatic life in the springs and their outflow are available. The previously designated (but not existing) Municipal and Domestic Supply beneficial use was removed through Basin Plan amendments effective in 2002.

QAPP Information:

Details on quality assurance were not provided with the data submittal.

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 76092, Temperature, water	Region 6
Keough Hot Springs

LOE ID:

27984

Pollutant:

Temperature, water

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Water Contact Recreation

Number of Samples:

198

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical monitoring (conventional pollutants only)

Data Used to Assess Water Quality:

The Owens Valley Indian Water Commission submitted data during the 2006-2007 solicitation process showing decreases in temperature in the ditch and pools as a result of changes in management of the cooling system used by the resort, and requested listing for violation of the water quality objective. The commission identified samples collected on dates when the resort cooling system was not operating and requested that they be considered to represent background conditions. For 2000, the data include nine samples collected when the resort cooling system was operating with temperatures more than 5 degrees F lower than temperatures at the same stations 1 to 9 days earlier when the cooling system was not operating. The Commission's letter states: "During the period of time from 10/22/06-10/26/06 Keough¿s Hot Springs Resort was closed for repair of the resort pools. Commission staff was able to take water temperature measurements at the Keough¿s Hot Ditch sites on 10/25/06 during the period when the resort cooling system had been off for several days. The October and November 2006 data shows that water temperatures at Keough¿s Hot Ditch changed significantly during the period when the Hot Springs Resort pools were closed for repairs and the cooling system was off (temperature measured on October 25th,
highlighted in yellow) as compared to the water temperatures measured 10-days before (October 5th) and 21-days after (November 15th), when the resort cooling system was operating. Comparing the October 5th (resort cooling system operating) and October 25th (resort cooling system off) water temperature (all measured between 10:00-10:15 am PST) the water at Keough¿s Hot Ditch was 5.4-8.1... [degrees] C (9.7-14.6...[degrees] F) cooler when the resort cooling system was operating than when it was shut off. A similar comparison between the temperatures measured on 10/25/06 (cooling system off) and 11/15/06 (cooling system operating) again shows that the water temperatures were again significantly cooler (4.8-7.8...[degrees] C; 8.7-14.0 ...[degrees] F) when the cooling system was operating." (This quotation has been edited to avoid problems with database formatting.) A total of 11 samples documented decreases in temperature greater than 5 degrees when the cooling system was operating compared to the previous samples takenwhen it was not operating.

Data Reference:

2007. Data for Keough Hot Ditch

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

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

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Two pools on Keough Hot Ditch (called "Upper" and "Lower" in the data) were sampled.

Temporal Representation:

Samples were collected at each station approximately twice monthly in 2000 and approximately monthly between 2001 and early 2007. During some years, concurrent samples were collected with two different instruments on some or all of the sampling runs. In addition to the 198 samples noted above, 47 concurrent samples were taken.

Environmental Conditions:

QAPP Information:

The data submittal included descriptions of the instruments used and noted that calibration records are available on request.

QAPP Information Reference(s):


DECISION ID	68584	Region 6
Keough Hot Springs

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:	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. Three annual average datapoints exceed the site-specific water quality objective for the Owens River, which is applicable through the Tributary Rule.. 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 in that one of the annual average datapoints is based on data for only two winter months. 3. Three of 3 annual average datapoints exceeded the water quality objective 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:	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 68584, Total Dissolved Solids	Region 6
Keough Hot Springs

LOE ID:

28046

Pollutant:

Total Dissolved Solids

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 monitoring (conventional pollutants only)

Data Used to Assess Water Quality:

The Owens Valley Indian Water Commission submitted data for Keough Hot Ditch during the 2006-2007 solicitation process. TDS was sampled approximately monthly in 2005, 2006 and early 2007. Concentrations of TDS in 52 samples ranged from 531 to 1192 mg/L. The annual average objective was violated in 3 of 3 years. (The third year included only two sampling events)

Data Reference:

2007. Data for Keough Hot Ditch

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

There is no site-specific water quality objective (SSO) for Total Dissolved Solids (TDS) in Keough Hot Springs. The objective for the Owens River (Station 23 in Lahontan Basin Plan Table 3-17 ) applies upstream through the tributary rule. It includes an annual average of 207 mg/L and a 90th percentile value of 343 mg/L.

Objective/Criterion Reference:

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

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Two pools on Keough Hot Ditch (called "Upper" and "Lower" in the data) were sampled.

Temporal Representation:

Samples were collected at each station approximately monthly between 2000 and early 2007.

Environmental Conditions:

QAPP Information:

The data submittal included descriptions of the instruments used and noted that calibration records are available on request.

QAPP Information Reference(s):


DECISION ID	77830	Region 6
Keough Hot Springs

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:	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 3.10 of the Listing Policy. Under section 3.10 a single line of evidence is necessary to assess listing status. One line of evidence are available in the administrative record to assess this pollutant. The applicable water quality objective is antidegradation based. Turbidity data are generally very low values and there is no obvious trend over time. No biological data are available for assessment of impacts on support of the Warm Freshwater Habitat beneficial use. Section 6.1.5.3 of the Listing Policy provides that if management measures have been implemented, only data collected after their implementation should be assessed. The resort operator at Keough Hot Springs has changed the operation of the resort cooling system since these turbidity data were collected. Changes in the temperature regime could affect biological and chemical processes that in turn affect turbidity. The available data do not necessarily reflect current conditions. . 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 satisfy the data quantity requirements of section 6.1.5 of the Policy. 3. The data do not show any trend toward degradation as would be required for listing under Section 3.10 of the Listing Policy. 4. No data collected since the implementation of management measures are available, and Section 6.1.5.3 of the Listing Policy provides that the older data should not be used for assessment. 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 77830, Turbidity	Region 6
Keough Hot Springs

LOE ID:

28017

Pollutant:

Turbidity

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

185

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical monitoring (conventional pollutants only)

Data Used to Assess Water Quality:

The Owens Valley Indian Water Commission submitted data for Keough Hot Ditch during the 2006-2007 solicitation process. Measurements of turbidity taken approximately twice monthly in 2000 and approximately monthly between 2001 and early 2007 (185 samples) ranged from 0 to 48 NTU. Most measurements were between 0 and 2 NTU.

Data Reference:

2007. Data for Keough Hot Ditch

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The Lahontan Basin Plan's regionwide objective for turbidity 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:

Two pools on Keough Hot Ditch (called "Upper" and "Lower" in the data) were sampled.

Temporal Representation:

Samples were collected at each station approximately twice a month in 2000 and approximately monthly between 2001 and early 2007.

Environmental Conditions:

QAPP Information:

The data submittal included descriptions of the instruments used and noted that calibration records are available on request.

QAPP Information Reference(s):


DECISION ID	75548	Region 6
Keough Hot Springs

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:	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. Sixteen of the samples exceed the provision of the water quality objective regarding change in pH. 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 satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. Sixteen of 190 samples exceeded the water quality objective 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:	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 75548, pH	Region 6
Keough Hot Springs

LOE ID:

28013

Pollutant:

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

190

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical monitoring (conventional pollutants only)

Data Used to Assess Water Quality:

The Owens Valley Indian Water Commission submitted data for Keough Hot Ditch during the 2006-2007 solicitation process. Measurements of pH taken approximately twice a month in 2000 and approximately monthly between 2001 and early 2007 (190 measurements) ranged from 7.91 to 9.61 units . There were 16 cases where pH changed more than a half unit in a given pool between one month and another. Naturally alkaline pH is to be expected in geothermal waters of the Lahontan Region.

Data Reference:

2007. Data for Keough Hot Ditch

SWAMP Data:

Non-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:

Two pools on Keough Hot Ditch (called "Upper" and "Lower" in the data) were sampled.

Temporal Representation:

Samples were collected at each station approximately twice a a month in 2000 and approximately monthly between 2001 and early 2007.

Environmental Conditions:

QAPP Information:

The data submittal included descriptions of the instruments used and noted that calibration records are available on request.

QAPP Information Reference(s):