### WATER QUALI'TY SURVEY FOR SELENIUM IN THE SACRAMENTO RIVER AND 

### ITS MAJOR TRIBUTARIES

Agricultural Unit California Regional Water Quality Control Board

Central Valley Region 3443 Routier Road Sacramento, California 95827-3098

February 1988CALIFORNIA REGIONAL WATER QUALITY ceNTROL BOARD CENTRAL VAlLEY REGION Board Members Karen Vercruse, Chair Clifford C. Wisdom, Vice Chair John S. Corkins Hugh V. Johns Paul 

### E. Simpson W. Steve Tompkins W. M. "Walt" Winn

William H. Crooks, Executive Officer

The staff involved in the preparation of this report are:
Jeanne E. Chilcott, Land arid Water Resources Specialist Dennis W. Westcot, Senior Land and Water ReSOL~ces Specialist

iSUMMARY

INTRODUCTION SELENIUM IN THE SACRAMENTO RIVER BASIN
TABLE OF CONTENTS
PAGE -1-
1
2 BASIN DESCRIPTION 2 Physical Characteristics 4 Beneficial Uses Pre-1984 Water Quality Data 5

SPECIAL SURVEYS STREAM MONITORING RESULTS 1984-89 14 12

14 DISCUSSION AND CONCLUSIONS
REFERENCES Appendix A Appendix B
Appendix C 18

Sampling Protocol A-I Selenium Stream Monitoring Network Locations B-1 Selenium Stream Monitoring Network Results 1984-1988 C-1

iiLIST OF TABLES PAGE

Table 1 Public Agencies Which Have Conducted Selenium Analyses

in the Sacramento River Basin 6 Table 2 Monitoring Stations with High Average Selenium

Concentrations as Measured Prior to 1984 7 Table 3 Reported (Pre-1984) Selenium Concentrations in the

Sacramento River Basin Exceeding EPA Drinking Water Criteria ( 10 ug/L) 8 Table 4 Selenium in the Sacramento Valley - Special Survey

Results 15 Table 5 Selenium in Fish Tissue as Reported in the SWRCB Toxics

Substances Monitoring Program for 1984, 1985, and 1986 17

LIST OF FIGURES Figure 1 Sacrament:o Basin of the Central Valley 3 Figure 2 Locations of Samples in Which Selenium Concentrations

Exceeded 10 ug/L as reported in Table 3 11 Figure 3 Selenium Stream Network Locations in the Sacramento

River Basin 1984-87 13

iiiSELENIUM IN THE SACRAMENTO RIVER BASIN

SUMMARY The Central Valley Regional Water Quality Control Board has completed a stream water quality survey for selenium in the Sacramento River and its tributaries to assess whether beneficial uses are being impacted. Historically, a large number of water samples, some taken as recently as 1984, showed selenium levels exceeding 10 ug/L, the present drinking water standard. Historical selenium concentrations as high as 390 ug/L were recorded in portions of the surface water in the Sacramento River Basin. This concentration is similar to the levels found in agricultural drainage water entering Kesterson Reservoir via the San Luis Drain in the San Joaquin River Basin. This survey was designed to verify historical data and locate potential sources of selenium loading. Special emphasis was placed on evaluating the contributions of point source discharges and non-point agricultural sources. Data obtained from the 1984-88 stream monitoring for total selenium in the Sacramento River Basin does not support historically recorded high selenium concentrations. During the current survey, measured selenium levels did not exceed the drinking water standard. Only eleven out of 366 water samples indicated concentrations exceeding 1 ug/L with a maximum of 1.6 ug/L. Monitoring also indicated that the major agricultural return flows and municipal and industrial discharges were not causing increased selenium levels in the Sacramento River or its tributaries and thus selenium levels were not adversely affecting existing or potential beneficial uses. Further evaluation of point and non-point source discharges is not needed at this time. Limi ted additional sampling was undertaken wi thin selected areas to verify historical data showing elevated levels in the water column and also to determine whether elevated selenium levels in the water column were responsible for elevated levels of selenium found in fish livers taken from these water bodies by the California Department of Fish and Game. No measurable results were reported except in the Black Butte Reservoir area where selenium concentrations in the water were reported as high as 0.8 ug/L.

INTRODUCTION Selenium concentrations are expected to remain low in surface waterways, however even small concentrations may have harmful effects on waterfowl and other aquatic life due to bioaccumulation through the food chain. Elevated levels of selenium are being found at certain locations in the San Joaquin Valley where subsurface agricultural drainage water is discharged into surface waterways or where natural surface runoff passes over or through known high selenium shale formations of the Tertiary or Cretaceous age. Formations in the San Joaquin Valley which are known to contain high selenium are not present in the Sacramento Valley, however other formations in the Sacramento Valley may contain high selenium shales. Such formations are like ly

1found throughout the Coast Range. Runoff

with flow from irrigated agriculture in the significant portion of the Sacramento Sacramento-San Joaquin Delta. from the Coast Range along Sacramento Valley make up a River discharge to the

Historical data on selenium concentrations in surface water of the Sacramento River Basin indicated periods of elevated selenium levels, especially from areas originating in the western portion of the basin. Selenium concentrations as high as 390 ug/L were recorded in surface water in the Sacramento River Basin. This concentration is similar to the levels found in agricultural drainage water entering Kesterson Reservoir via the San Luis Drain(USGS, 1985). Because of the concern over the effects that these selenium levels may have on aquatic life in both the River Basin and the Delta, a program of water quality monitoring was initiated to help define the sources of selenium and whether further assessment of waste discharge regulation was needed. As the historical discharges of high background level in quality monitoring following goals: data proved too limited to locate potential selenium to surface water or to define the the Sacramento River and its tributaries, a water network was developed. The program had the
a) Verify preliminary data showing high selenium concentrations in the Sacramento River tributaries flowing from the western part of the river basin; b) assess the relative significance of non-point agricultural discharges as part of the total selenium load to the River and Delta and assess whether further evaluation of non-point agricultural sources, including tile drains, in the Sacramento Valley is needed; c) assess whether further evaluation of point source discharges is needed; and d) define whether beneficial uses are being impacted by selenium concentrations in the Sacramento River, its tributaries and as it enters the Delta. This report reviews historical data and presents the selenium levels in the Sacramento River Basin as monitored during the period April 1984 to April 1988.

BASIN DESCRIPTION Physical Character i stics The Sacramento River Basin is located in the northern half of the Central Valley of California. It is composed of 19 counties, covers 27,215 square miles, and produces 32% of the annual water supply for California (SWRCB, 1980). The geographical boundaries include the Cascade Range and Klamath Mountains to the North; American River and

2AVERAGE ANNUAL PRECIPITATION - 51.590.000 acre-feet

AVERAGE ANNUAL RUNOFF - 22.390.000 acre-feet

IRRIGA TED LAND - 2.084.000 acres
POPULATION - 1.674.000



### BAS IN

o Quincy

10 

# . 20

1 1 0

I .Mlll.5



## Figure 1 SACRAMENTO BASIN--tENTRAL VALLEY
3Putah Creek basins to the south; Sierra Nevada crests to the east; and

North Coast
. Range crest to the west (Figure 1). The valley floor portion of the river basin has a Mediterranean climate with hot summers and mild winters. The average temperatures in the valley range from 44° F (January) to 80°F (July), with a mean seasonal precipitation of 23 inches, most all of which falls in the winter months. The Sacramento River serves as the main

. drainage artery for the valley. Major tributary inflows below Shasta Lake include the Bear, Yuba, Feather, and American Rivers as well as numerous s~rearns and agricultural return flows. River flow is regulated year round through the use of darns and bypasses. Major regulatory darns include Shasta and Keswick on the Sacramento River, Whiskeytown on Clear Creek, Black Butte on Stony Creek, Oroville on the Feather River, Folsom and Natomas on the American River and Englebright and Camp Far West on the Yuba and Bear Rivers, respectively. Surface water storage exceeds 10.5 million acre feet behind Whiskeytown, Folsom, Oroville and Shasta Darns alone. The Sacramento Valley is a major agricultural area, and a significant portion of the river flow is directed through farmland with only return flows reaching the river. Water, Irrigation, and Reclamation Districts operate gates which control flow to and from these districts. Major agricultural surface drainage inflows to the Sacramento River include Butte Creek at Meridian, Reclamation District 108 Drain, Colusa Basin Drain, and the Sacramento Slough. There are very few subsurface agricultural drains in the basin. Winter storm runoff can drastically increases river flow; e.g. from 9,400 cfs to 52,500 cfs at the City of Freeport during water year 1980-81. Areas such as the Sutter and Yolo Bypasses were developed to contain overflo~. This overflow eventually finds its way back into the Sacramento River or enters directly into the Sacramento-San Joaquin Delta near Rio Vista.

Beneficial Uses The Sacramento River provides a variety of beneficial uses as defined in the Water Quality Control Plan for the Sacramento River Basin (5A) including: munic i pal and domestic supply; agricultural supply; industrial supply; freshwater habitat; migration; spawning; wildlife habitat; recreation; and navigation. The major diversion for drinking water is at the City of Sacramento, supplying a population of approximately 280,000. Additional diversions occur at the cities of Redding and Red Bluff. In addition to direct diversions in the Sacramento River Basin, excess water yield from the basin is redirected through the Sacramento-San Joaquin Delta to the Delta-Mendota Canal and the California Aqueduct which supply water to agriculture and communities south of the Delta. Agriculture is the major water user in the Sacramento Basin through a highly developed system of diversions and canals. A significant use for diverted water is wildlife habitat in several federal, state and private wildlife refuges. Power development is the principal industrial use in the Sacramento River Basin. The Sacramento River and its tributaries also support a variety

4of freshwater and anadromous sport fisheries. Studies conducted by the

California Department of Fish and Game and the U.S. Fish and Wildlife Service have shown that the river and its tributaries are the principal migration routes and spawning grounds of White Sturgeon, Striped Bass, Chinook Salmon and American Shad.
Pre-1984 Water Quality Data Numerous surface water analyses for selenium have been conducted in the Sacramento River Basin by various state, local and federal agencies (Table 1). The California Department of Water Resources (DWR) has compiled the mos t extensive data base. The U.S. Forest Service annually checks for trace elements in water sources (streams, springs, and wells) supplying their campgrounds. Selenium analyses for surface water conducted by government agencies are recorded in the U.S. Environmental Protection Agency data storage system (STORET). It should be noted that some stations report duplicate data published by both DWR and the U.S. Geological Survey (USGS). There are 160 surface water monitoring stations recorded in STORET for the Sacramento Valley; 100 of these show only a one time analysis. Stations in the Sacramento Valley with a more continuous historical record are Greens Landing, Freeport, City of Sacramento Water Treatment Plant, and Keswick Reservoir on the Sacramento River, Nicolaus and Gridley on the Feather River, City of Sacramento Water Treatment Plant on the American River and several sites within the Stony Creek Watershed. Different water quality monitoring agencies conducted selenium analyses under a variety of analytical methods and quality control procedures. Most samples collected before 1984 by agencies other than the USGS were not analyzed by the hydride generation technique, the currently accepted analytical technique. In 1975, the USGS began using atomic adsorption with hydride generation for low level selenium analysis. Values reported prior to 1975 may not be reliable. DWR used the colormetric method until July 1984 when the laboratory switched to hydride generation. Selenium data for low level detection and quantification as reported by DWR before July 1984 are of questionable value unless rechecked by the hydride generation technique. Most selenium concentrations reported in surface water in the Sacramento River Basin prior to 1984 are below the drinking water standard of 10 ug / L. Stations with average concentrations approaching or exceeding this standard are listed in Table 2. In the 1700+ water samples analyzed prior to 1984, DWR reported 79 concentrations exceeding the drinking water standard of 10 ug/L for total selenium (Table " 3). The maximum measured concentrations were 390 ug/L for total selenium and 30 ug/L for dissolved selenium. Locations of extreme values a r e scattered throughout the basin (Figure 2). Most of these values were reported by DWR after 1980 but prior to 1984. Of the previous sites showing elevated selenium values, only six were monitored after 1984 and none confirmed the original results.

5TABLE 1
PUBLIC AGENCIES WHICH HAVE CONDUCTED SELENIUM ANALYSES IN THE SACRAMENTO RIVER BASIN

Federal U.S. Geological Survey U.S. Bureau of Reclamation U. S. Forest Service (El Dorado, Lassen, Mendocino, Modoc, Plumas, Shasta-Trinity, and Tahoe National Forests)
State Department of Water Resources State Water Resources Control Board Central Valley Regional Water Quality Control Board Local City of Sacramento (Water Treatment Plant) County of Sacramento (Regional Wastewater Treatment Plant)

Of the samples taken prior to 1984, the highest reported selenium concentration occurred principally along the western half of the basin. Samples taken in the Stony Creek Watershed and the Clear Lake area showed consistently high values. Between 1980 and 1981, DWR conducted a trace element survey in the Stony Creek area in conjunction with the Thomes-Newville water storage project study(DWR Files). Total selenium concentrations regularly exceeded the 10 ug/L standard with the highest reported selenium at 240 ug/L. Samples taken in the Clear Lake area have shown concentrations reaching 80 ug/L for total selenium. The Colusa Basin Drain which receives runoff from the westside streams, as well as a significant amount of irrigation return flow, showed the highest concentration at 390 ug/L total selenium in 1981. Current monthly monitoring of selenium is limited to grab samples near the confluence of the American and Sacramento Rivers by the City of Sacramento as part of its drinking water program. Monthly depth integrated, cross-sectional samples are also taken at Freeport by the USGS. Laboratory procedures and large fluctuations in selenium concentrations make the data prior to 1984 suspect. Extremely high values, such as those reaching over 100 ug/L were never verified or incorporated into a yearly trend. Since the validity of historical data is in question, a background level for selenium in the Sacramento River or its tributaries cannot be established from the existing data record. Al though overall concentrations are thought to be below 10 ug/L, instances of extremely high concentrations cannot simply be disregarded as analytical error. Their cause, whether natural or the result of

6TabLe 2. Monitoring Stations with High Average SeLenium Concentrations as Measured Prior to 1984.

CONCENTRATION (UG/L)

TYPE.!, SAMPLE NO. AVERAGE RANGE PERIOD OF RECORD LOCATION AGENCY
Cache creek nr. Lower Lake DIJR D 10 9 0·30 5/71·5/81 Stony Creek ab. Grindstone DIJR T 17 20 0·150 8/80·3/82
Thomes Creek at Paskenta DIJR T 17 15.3 0-100 8/80-3/82
Sacramento R. ab. Stony Creek DIJR D 19 22.1 0-110 8/80-5/82
Grindstone Ck. nr. ELk Creek DIJR T 17 24.7 0-200 8/80-3/82 Stony Creek nr. Newville DWR T 15 10.7 0-50 8/80-3/82
Stony Creek bL. B Lack Butte DIJR T 17 21.8 0-60 8/80-3/82 CoLusa Basin Drain at Knights Ldg. DIJR T 14 42.9 0-390 3/72-3/82

- - - - - - - - 

### - -
.................................. - ..............................................................................................................................................................

T 

## = totaL

D 

## = dissolved

Note: Shasta Lake averaged 10 ug/L in 1983, but recorded no values exceeding 10 ug/L.

7Table 3. Reported (pre'1984) selenium concentrations in the Sacramento River Basin exceeding EPA drinking water criteria (>10 ug/L).

--------------------------------------------------------------_ .... _--------------------------- SELEN IUM CONC. (UG/L) I.D. .L STATION LOCATIONb AGENCylt DATE TOTAL DISSOLVED

...........................................................................................................................................................................................

A2130000 Sacramento R A Delta DWR 3/23/78 20 3/11/80 20

2 A2101000 Sacramento R A Keswick DWR 5/29/79 30 3/25/80 20
3 A0350000 Thomes Creek A Paskenta DWR 3/26/80 30 1/22/81 20 9/28/81 30 12/29/81 20 2/24/82 100 3/31/82 40

4 A3117500 Stony Ck NF A Newville DWR 1/22/81 20 10/28/81 20 12/29/81 50

5 A3130200 Grindstone Ck NR Elk Ck DWR 6/30/81 20 7/29/81 40 9/28/81 30 12/29/81 40 2/24/82 200

6 A3125000 Stony Creek NR Fruto DWR 10/22/80 30 1/23/81 20 7 A3125300 Stony C AB Grindstone Ck DWR 10/22/80 20 1/23/81 20 5/27/81 20 7/29/81 20 8/31/81 20 9/28/81 40 12/29/81 150 3/31/82 20

8 A3R94892205 Black Butte Reservoir DWR 6/22/81 70 8/21/81 30 12/23/81 30

8Table 3. Reported (pre·1984) selenium concentrations in the Sacramento River Basin exceeding EPA drinking water criteria (>10 ug/L) •

................. --------------- .... - ................. - ...... - ........ _--_ .... ------------------_ .. ------ ............ -- .. - .... -- SELENIUM CONC. (UG/L) I.D. .!.t STATION LOCATION.!t AGENCy1J DATE TOTAL DISSOLVED

.. -_ ........ -_ .......................... -_ ............................................ ----_ ........ -_ .................... 

### -_ .......... -_ .............................. _- 9 A311000 Stony Ck A Black Butte DIJR 10/21/80 40 Dam 1/2U81 30 4/28/81 20 7/29/81 60 9/28/81 3d 12/29/81 40 2/24/82 60 3/31/82 50
10 A0263000 Sacramento R A Hamilton DIJR 5/30/79 30 City 4/28/83 30

11 A0261000 Sac R AB Big Chico Creek D'WR 3/27/80 20

12 A026500·A Sacramento R AB Stony Ck DIJR 10/21/80 40 1/23/81 20 7/29/81 110 9/28/81 30 11/30/81 20 12/30/81 50 1/29/82 30 2/24/82 20 3/31/82 20 4/28/82 30 5/26/82 40
13 A0516500 Feather River NR Gridley DIJR 5/25/82 20

14 A0615000 Yuba River NR Marysville DIJR 4/27/82 20

15 A8R90502322 Indian Valley Res at Dam DIJR 9/15/81 20

16 A8L90072417 CL23 Oaks Arm CL4 DIJR 11/8/78 20 9/23/82 40

17 A8185792406 Clear Lake Lower Arm CL3 DIJR 11/8/78 20 9/15/81 30 9/23/82 80

9Table 3. Reported (pre·1984) selenium concentrations in the Sacramento River Basin exceeding EPA drinking water criteria (>10 ug/L).

I.D. .L STAT ION LOCATIONk AGENCYl, DATE SELENIUM CONC. (UG/L) TOTAL DISSOLVED

18 11451000 Cache Creek NR Lower Lake USGS

19 A0294710 Colusa Basin Drain NR Knights Landing DWR

20 American R BL Nimbus Dam DWR

A0718000
21 A0714010 American 

### R A Sac Water DWR Treatment Plant

22 11447810 Sacramento R A Greens Ldg USGS

B9D82071327 Sacramento R A Greens Ldg DWR

23 B9D81781448 cache slu A Vallejo Pupl DWR

.!, As depicted in Figure 2. 

## z. A 

### = at BL below AB above NR near

~ DWR 

### = Department of Water Resources. USGS 

## = U.S. Geological Survey

10 4/5/79 9/18/80
7/31/81 390 9/29/81 60 11/24/81 60 1/27/82 20 3/24/82 20
6/14/82
4/27/82 6/14/82
6/18/80

10/21/81 1/19/83
6/15/83 30 20

30
20 30
20

20 20
30

## 'et. Figure 2. 

### Locations of samples in 

### which selenium concentrations exceeded 10 ug/L as reported in Table 

### 3. (Sacramento River Basin 1971 - 1983)

Cr ove

11 MILESwaste discharges or agricultural practices, raises a concern for its

impact on existing beneficial uses, especially those associated with wildlife habitat. The following sections of this report describe efforts to assess the validity of the available data and the potential sources of high selenium concentrations in the river basin.

STREAM MONITORING RESULTS 1984-8&'
Between 24 April 1984 and 12 April 1988, 366 water samples and 6 sediment composites were collected in the Sacramento Valley by Regional Board staff and analyzed for total selenium. Sampling protocol is outlined in Appendix A. Sampling locations were chosen to characterize the major tributary flows, assess levels impacting beneficial uses, as well as identify potential loading sources. Site selection considered historical data as well as site access. Twenty-five conti nuous sites were located on maj or tributaries with four additional stations along the Sacramento River. Spot sampling was also conducted in a variety of other locations during the course of the study. Station identification and descriptions are listed in Appendix B. Locations wi thin the basin are shown in Figure 3. Samples were spli t and concentrations verified by a number of different laboratories. Additional water samples were taken at 7 sites in and near Lake Berryessa. Samples were also taken in Lake Shasta and the ~1cCloud River to determine whether elevated levels of selenium in the water column were responsible for the elevated levels of selenium found in fish livers taken from fish in this area by the California Department of Fish and Game. A special survey in Black Butte Reservoir which inc luded composite sediment sampling was conducted in October 1986 to verify historical data that showed high values in the reservoir discharge. The initial surveys were conducted in April, May, June, and July of 1984, and March 1985. The sampling periods were chosen to reflect pre-irrigation, irrigation, rice field drainage, and storm runoff periods. During August and September 1986, January 1987, and April 1988, four additional surveys were conducted. The January 1987 survey represented runoff after a storm event wh i Le the April 1988 survey represented flow under conditions of a critically dry year. Of the 366 analyses for total selenium conducted as part of this stream surv ey, only eleven values were confirmed at greater than 1 ug/L. The maximum reported value was 1.6 ug /L from a sample taken in Stony Creek above Black Butte Reservoir. Other concentrations of 1 ug/L were scattered between Stony Creek above and below Black Butte Reservoir, Kendricks and Salt Creeks above Black Butte Reservoir, Cottonwood Creek at Interstate Highway 5, Spring Creek below the debris dam, Natomas East Main Drain at Del Paso Road, and the Sacramento River at Hood. Although no statistical analysis has been conducted, it does not appear that selenium concentrations were different between the storm-runoff survey and the survey conducted under a critically dry year conditions. Actual laboratory values are listed in Appendix C.

12

## •••••

.

## --..

. ../-- Figure 3. Selenium stream network

locations in the Sacramento R iver Ba si n as reported in AppendixB.

1984 - 1987 

## r r __"- '

_ . ,/ -- I J r.,'"..

\



# '- 5

\ 

## " \ 

# - 

# ..•

28 <.

~ 

# -
....'-

~~/ 1

ere",.

13 "I~t SSPECIAL SURVEYS

Additional water and sediment surveys were conducted in areas suspect of high selenium concentrations based either on historical data or relatively high concentrations detected in fish livers during the 1985 Toxics Substances Monitoring Program (SWRCB, 1986). Areas of concern included Lake Berry essa, Black Butte Reservoir, and the McCloud River. In July 1984, additional water samples were taken by Regional Board staff in the Lake Berryessa area to verify low positive results from Putah Creek above and below the lake found during a June 1984 surve y . The laboratory results for the June 1984 survey were subsequentl y determined to be in error. Analyses were completed by the USGS for the July 1984 samples and all results were below the 1 ug/L detection limit. Sediment samples taken during the same survey showed selenium concentrations below the detection limit of 0.1 0 mg/Kg. In October 1986, sediment and water samples were taken from the Black Butte Reserv oir area, to verify historical data reporting selenium le v els up to 240 ug / L (DWR files) and in response to selenium levels ranging from 0.7 mg / Kg to 1.9 mg/Kg detected in fish li v ers by th e California Department of Fish and Game during 1984 and 1985. Sediment samples were taken from Stony Creek entering the reservoir, from the dam overflow area, and from the lake behind the reservoir. Sed i.rue n t. concentrations ranged from 0.05 to 0.15 mg/Kg selenium. The water concentrations were 0.7 and 0.8 ug/L total selenium for Stony Creek and Black Butte Reservoir, respectively. The 1984 Toxic Substances Monitoring Program reported high selenium concentrations (25 and 35 mg/Kg) in fish flesh collected from Kesterson Reservoir, a known selenium ric h site(SWRCB, 1985). The second highest valleywid e concentration, 9.1 mg / Kg in rainbo w trout liver was collected in the Shasta Lake / McCloud Ri v er ar e a. In response to high selenium levels detected in the trout li ve r, grab samples wer e collected to determine selenium concentrations in the water column for the Shasta Lake/McCloud River area. Resulting concentrations were all below the 0.6 ug /L detection limit. Additional fish flesh analyses conducted later by the California Department of Fish and Game reported selenium concentrations at less than 0.2 mg/Kg wet weight. A summary of special stream survey data is shown in Table 4.

DISCU SSION AND CONCLUSIONS Data obtained from the 1984-88 stream monitoring for total s e lenium in the Sacramento Ri v er Basin does not support historically recorded concentrations. During this survey, reported concentrations never exceeded the 10 ug/L drinking water standard even though data prior to 1984 reported over 100 ug/L. The current data, based on 366 water analyses, indicates extremely low total selenium concentrations in the Sacramento River and its main tributaries. The maximum reported concentration was 1.6 ug/L.

14Table 4. Selenium in the Sacramento Valley Special Survey Results

Location selenium concentrations water (ug/L) sediment (mg/Kg) LAKE BERRYESSA Lake Berryessa @ Steel Canyon " " @ trailer park Pope Creek @ mouth

II " @ headwaters Putah Creek @ mouth

" II @ headwaters Capell Creek <1 «1) 1 <1 <0.10 <0.10 <-0.10 <0.10 <0.10 <0.10

BLACK BUTTE RESERVOIR Stony Creek above BBR Black Butte Reservoir OVerflow below reservoir 0.7 0.8 0.15 0.05 0.10 McCLOUD RIVER/SHASTA LAKE McCloud River @ Shasta Lake Pit River @ Shasta Lake McCloud R. @ Fowler Campground Mud Creek 

### @ HWY 89 McCloud R. ~ mile downstream of reservoir Sacramento River @ Cypress Bridge (Redding) <0.6 <0.6 <0.6 <0.6 <0.6
<0.6

15Additional water column data from a late 1984 survey conducted by the

U.S. Bureau of Reclamation (USBR) supports the findings in this report that the Sacramento River does not carry elevated levels of total selenium. From the limited USBR data collected in the Sacramento River, selenium concentrations never exceeded 0.06 ug/L. A trend of decreasing selenium concentrations moving north from the Delta is noted in the USBR report (Brown, 1985). The USBR data and the data reported here indicate extremely low background levels of total selenium in the Sacramento River but the limited data set does not allow quantification of the selenium loading from the Sacramento River Basin to the Sacramento-San Joaquin Delta. During the stream monitoring, average selenium concentrations were found to be less than 1 ug/L for coast range streams, Sierra streams, and surface agricultural drains. The low levels prove inconclusive as to whether any of the three general areas is a major selenium loading source. However, only samples from westside streams had concentrations reported at or greater than 1.0 ug/L, but due to the low levels detected, it is not possible to quantify selenium loadings. Studies conducted under the Toxic Substances Monitoring Program of the State Water Resources Control Board have shown detectable levels of selenium in fish from the Sacramento Valley (Table 5). Although a follow-up water survey and fish flesh analyses indicated low selenium concentrations, data is currently not available to isolate the source for the original high levels detected in fish livers. Current data in the San Joaquin River Basin shows agricultural subsurface drainage as a major selenium loading to both the San Joaquin River and the San Joaquin Delta. Major surface agricultural return flows in the Sacramento River Basin (i.e., the Colusa Basin Drain and Sacramento Slough) did not contain levels of selenium exceeding 1 ug / L. Subsurface drainage systems are not widespread in the Sacramento Valley, however, two areas are of special concern. The first is the open drains that serve the area upstream of the Modoc National Wildlife Refuge in the Alturas area. A survey of drainage water quality in this area is presently underway by staff of the Central Valley Regional Water Quality Control Board. The second area is in the Stony Creek-Cache Creek Fan and Interfan areas where water from the recent Tehema-Colusa Canal may cause drainage problems in some lower lying areas. Ini tial plans are underway for locali zed subsurface drainage systems in that area and initial shallow ground water samples in on e area show varying selenium levels up to 32 ug/L (Boyle Engineering, 1986) . Results from this river basin survey do not indicate that point source discharges of selenium from industrial or municipal sources are impacting beneficial uses in the Sacramento River nor are they causing elevated selenium levels in surface water. A recent survey of significant municipal discharges in the river basin was conducted by staff of the Regional Board. Only two dischargers, the cities of Woodland and Davis showed selenium concentrations above the detection level of 1 ug/L but concentrations were still below the 10 ug / L drinking water standard. Follow-up surveys and monitoring are underway at these two sites (Westcot and Gonzalez, 1988).

16Tabl e 5. Selenium in fish tiss u e a s re po r ted in the SWRCB Toxics Subs t anc e s Moni to r i ng P r ogram for

1 984, 1985, and 1986

sel e nium c on c ent r at i on (mg/Kg w e t we i gh t )!/ 1984 1985 1986 Fl e sh Liv er Fl e sh Liver Flesh Liver Lo c a t ion 9.1

i-' -J McCloud Riv e r/Shas t a Lak e Sac Riv e r @ Shas t a Dam Sac Riv e r @ K es wick Black Bu tte R ese rvoir Stony G or g e R eservo ir Eas t Pa r k R e s ervo ir Rollin s R eservo ir Indian Vall ey R e s ervoir Lake B er rye s s a @ Pop e Cre e k Lake B er ry es sa @ Pu t ah Cr e ek Lak e B e rry ess a @ C ap e ll Cr ee k Fea t her R i v er @ N ic olaus Sacrame n t o S lough Natomas Eas t Main Drain Sac Riv er @ Cl ar ksburg B e ach Lak e Sac R i v e r @ H o od 1.5 0.6(0.6) 1.1 <0.2 0.4(0.4) 6.5(2.6) 3.1 4.2 0.3(0.4) 0.7(0.9)

1.3(2.1) 4 1.3(1.9)

1.4(1.2) 1.3 1.3 1.1 0.5 1.2 0.26

~~38(0.3;)(0.21)~/

0.29 0.17 -- 0.17(0.14XO.39)]/



## 11 All data as re p o r t edby the californiaDepartmen tof Fish and Game . 

## ?:J All values r e p re sentconcentrationsin fish fl e sh.A similar survey was conducted by staff of the Regional Board for

selected industrial discharges. None of those sampled showed selenium concentrations above the detection level of 1 ug/L. Because of the low levels encountered with both municipal and industrial discharges, further investigations are not warranted at this time. Certain activities however, do have a high potential for encountering selenium deposits. The most likely are the mining and geothermal activities in the coastal foothills. Periodic chec k s of these wastewater discharges should be conducted to ensure continued protection of beneficial uses (Westcot and Gonzalez, 1988).

REFERENCES Boyle Engineering Corporation. A Report on Monitoring and Water Qualit y Analyses Made for the Seepage/Drainage Inv estigation of Colusa Zone of Benefit 2, November 1986. Deli v ery Order No. 5-CS-20-03270. Brown, R., 1985. Selenium in the Sacramento-San Joaquin Estuary - A Summary of Available Data. Department of Water Resources File Report. Burau, R. G. 1985. Preliminary Report to the Central Valley Regional Water Quality Control Board on Laboratory Performance for Selenium Analyses of Reference Water Samples. Central Valley Regional Board files. Presser, T. S. and Barnes, I. 1985. Dissolved Constituents Including Selenium in Waters in the Vicinity of Kest e rson National Wildlife Refuge and th e West Grassland, Fresno and Merced Counties, California. U. S. Geological Survey, Water Resources Investigations Report No. 85-4220. State Department of Fish and Game. 1987. Program 1986 Data Report. Toxic Substances Monitoring
State Water Resources Control Board. 1984. Toxic Substances Monitoring Program. Press Release. State Water Resources Control Board. 1986. Toxic Substances Monitoring Program, 1984. ~vater Quality Monitoring Report No. 86-4WQ.
State Wat e r Resources Control Board. 1987. To x ic Substances Monitoring Program, 1985. Water Quality Monitoring Report No. 87-1WQ. State Water Resources Control Board. 1975. Report for the Sacramento River Basin (SA). Water Quality Control Plan Volume I and Volume II. Westcot, D. W. and Gonzalez, J. L. 1988. Municipal and Industrial Discharge Survey for Selenium. Central Valley Regional Water Quality Control Board Report, October, 1988.

18

## APPENDIX A

## APPENDIX A

Sampling Pr o t oc ol Two methods we r e u s ed for c ollecting water samp les for t o tal s elenium analysis s 

## direct collection from stre am flow and collection using a 2.5 gallon acid-rinsed stainless steel bucket. In both cases, final samples were stored in acid-washed 6 oz. linear polyethylene plasti c bottles and p reserved with a c i d to a pH < 2.

~ 4 hen us ing t he bu cke t, wat e r wa s c olle ct ed fr om the c enter o f a bridge on the downs tr e am si de. The bu cket \'/asri ns ed two times wi 

## th s ampl e bef o re final collection

. The sample wa s then poured directly from the bucket to the acid-washed sampling bottle. Care was taken to avoid disturbing bottom s ediments and to collect e ach sample as clos e to the center of flow a s po ss i b le
. In add i t ion t o wa ter s ample s t aken f o r t o tal selenium ana l ysi s , fiel d data was c olle c ted for electrical c onductivity (EC) and temper a ture. EC was measured using a Myr on OS Meter, model 5 32 MI. Standard procedures were followed which included calibration at each site and rinsing the cell cup three times with samp le before taking the reading

. A s tanda rd Fahrenhei t thermometer was us ed t o measure temp er a ture either by di r e c t pla c emen t i nto str eam flow or int o the buc ke t. Temperature me a surements wer e taken after s elenium sampling and EC analysis were c ompleted
. In all c a se s , order of collection were as follow s : 1. water sampl e for s eleni um analys i s; 2 . ele c tri c al conductivity; 3. temper a ture. F or e ach s amp ling run, a travel blank was p repa red by 

## filli ng a 6 o z . ac i d

- washed l ine a r p ol yethy lene pl a sti c c ontaine r w ith deionized water and ac idif y i ng w ith a c i d to pH <2 . At e ach s ite , the tr avel blank wa s op ened and pl ac ed in t he vicinity during wa ter collection for selenium ana lysis. The blank Vias c losed before EC and t emperature me a surements were taken. Sediment Mo st sedimen t s we r e c ollec t ed u s ing a mod ified brass E c kman samp le r . F or sediments c olle c ted withi n l akes, the Eckman was dropped from a boa t and each " s amp le ' was a c omposite of four colle c tions. Ea ch colle c tion c onsisted of approximately 100 grams from the top two inches of bottom sediment

. The sampler vias ac i 

## d-washed and rinsed with surrounding surface wa ter between E ach site. F o r sediments c olle ct ed in sha ll ow s tre ams, a mod ified so il aug er was used. For e ach s ite , the top two inche s of bottom s ed iment wa s co lle c ted in

A-I

### Appen d i x P.



### e c i 

### d

-washed two

-inch PVC 

### pipe. Six collections taken as a random transect of the stream \"tere composited f or each site s ample

. All soil samples were frozen in plastic bags until analysis by the 

## con t racted l aboratory.

A - 2

## APPENDIX B

## SELENIUM STREAM NETWORK SAMPLING SITES

10. 

## Description
T8-100 Travel blank. De-ionized water taken from the CVWQCB laboratory. SV-l Putah Creek at HWY 128 bridge below Monticello Dam (Lake Berryessa). Sample taken from shore at northwest corner of bridge. SV-2 Upper arm of Lake Berryessa. Taken from west bank at the end of Stage Coach Road. Putah Creek at left bank of HWY 29 bridge. SV-2B 

## SV-3 Cache Creek bel ow 

## Clear Lake at Dam Road Bri dge (off HWY 53). Bucket sample taken from center of bridge, downstream side. SV-~ Cole and Kelsey Creeks confluence above Clear Lake. Bucket sample taken from bridge leading to Clear Lake State Park boat launch. 

## SV-5 Middle Creek above Clear Lake, downstream of HWY 20. Sampled from road running along left bank of creek. SV-58 Scotts Creek above Clear Lake from HWY 29 bridge. Bucket sample, downs t 

## ream side. 

## SV-6 Cache Creek from right bank at 

## HWY 20 bridge. SV-7 Stony Creek above Black Butte Reservoir. Bucket sample from downstream side of Black Butte Road bridge

. SV-8 Stony Creek below Black Butte Reservoir. From left bank dovns 

## tream of Newville Road bridge. SV-9 Kendricks and Salt Creeks above Black Butte Reservoir. Bucket sample, downstream side of Newville Road bridge. SV-10 Thomes Creek at Road A9 

## bridge near Paskenta. Bucket sample, downstream side of Newville Road bridge. Cottonwood Creek near HWY 5. Left bank off dirt road leading to railroad tracks under H~!Y 5 bridge. 

# sv-n

B-1

### 1 0. 

## Description

SV

- 12 Clear Creek below Whiskeytown Reservoir. Mid

stream s amp l e dovmst r eam of Paige Bar Road Br i dge
. SV

- 13 R i ght bank of Spr i ng Creek a t D ebr i s Dam spi 11. 

## SV-l ~ Mill Creek at H\~Y 99 

## br i dge. Bucket sample, downstream s i de
. SV

- 1S Lef t bank of Bi g Chic o Creek at 6th Str eet br idge in Chi co . SV-16 Big 

## Chico Creek above the Sac ramento River

. Bucket samp le , downstream of Ri ve r Road bridge. SV-1 7 Fe a the r Ri ver ne a r E a s t Grid l ey Road . Righ t bank , above bri dg e. SV- IB Yuba River i n Ma rys v ille . L eft bank above Ramirez Street Bridge. SV -1 9 Butte Cr e ek above Sacramento Rive r . Bucket s amp l e taken from ga te re l ease we 

## l kway o ff But te Slough Road. SV- 20 Colusa Bas i n Drain at Road 9 9 E
. Bucke t samp l e , d owns 

## tream of bri dg e . SV

- 21 Fe ather Ri ver downstr
- eam 

## o f HWY 99 

## br i dg e. L e f t bank. SV- 22 Nat oma s E ast Dr a i nage Cana l f rom Elkhorn Bl vd
. Bridge. Bu c ke t sample, upst ream o f bridge. Natomas E ast Dra i nage C ana l f rom Del Paso Road Bridge. Bu c ket samp le, downstream s ide. SV-22, fJ,

SV

- 23 Amer i can R iver be l ow Nimbu s Fi sh Hatche ry along le f t bank
. SV- 23A American Ri ver at S unri s e B l vd
. fo o t bridge

. Bu cket sample downst r e am s i de. SV- 2 ~ Sacramento Slough above RO 1000 di scharg e. Bucket s ample, downstream side of br i dge. SV

- 25 SV

- 2 6 Toe Dr a in above Ca che S l ough by bo a t
. RD 108 dis charge above pump house
.

B-2

## rD.

SV-27 SV-28
Sacramento River Sites SR-P, 

## SR-B

SR-C SR-O SR-E SR-F SR-G SR-H Description Feather River at West Catlett Rd. Sutter Bypass at Tarke Rd.

Sacramento River below Keswick Dam - right bank. Sacramento River below Hamilton City. Left bank where River Road becomes gravel. Sacramento River at Hamilton City. Sacramento River at Colusa. Sacramento River at Grimes Boat Marina from pier. Sacramento River at Vi 11 

## age Mari na Sacramento River at Hood. Sacramento River below Rio Vista Bridge. (By boat, mid-channel

. )

B-3

## APPENDIX CSELENIUM STREAM NETWORK SAMPLING RESULTS

-------------------------------------------------------------- .... - .. ------------------ ....• ---------------- .... ---- RWQCB TEMP EC SELENIUM CONCENTRATIONS (ug/L) 

### * LOCATION ID DATE TIME ( F) umhos/cm ANLAB CAL USGS DWR SDSU

.................................................... -_ ......................................•.......... 

### --_ .......................................... "' ...................... -_ ............ 

### -_ .................. TRAVEL BLANK TB100 4/24/84 1535 <2 <2 5/17/84 0630 70 2 <2 5/30/84 1900 70 2 <2 <2 6/25/84 0645 68 3 <2 7/17/84 1530 83 7 <1 3/8/85 1500 70 5 <.6 8/20/86 0700 <0.2 1/5/87 0600 <0.2

PUTAH CREEK BELOW SV·1 4/25/84 0730 50 285 4 <2 LAKE BERRYESSA 5/17/84 0745 52 250 <2 5/31/84 0720 52 245 <2 <2 6/25/84 0755 54 260 <2 7/18/84 0720 53 255 <1 3/8/85 1600 50 280 <.6 8/20/86 0815 0.2 1/5/87 0710 56 300 0.4 4/11/88 1113 54 300 <0.2

UPPER ARM SV·2 4/25/84 0900 60 370 2 <2 LAKE BERRYESSA 5/17/84 0850 67 365 <2 5/31/84 0835 74 340 <2 <2 6/25/84 0900 79 355 <2 7/18/84 0830 85 370 <1 3/8/85 1700 48 275 <.6

PUTAH CREEK ABOVE SV·2B 5/17/84 0925 60 250 <2 LAKE BERRYESSA 5/31/84 0905 65 235 <2 <2 6/25/84 0935 70 250 <2 7/18/84 0905 76 265 <1 3/8/85 1730 50 190 <.6 8/20/86 0940 <0.2 1/5/87 0835 48 215 <0.2 4/11/88 1240 73 320 0.4

CACHE CREEK BELOW SV·3 4/25/84 1000 57 210 <2 <2 CLEAR LAKE 5/17/84 0950 61 195 <2 5/31/84 0930 71 185 <2 <2 6/25/84 1005 74 190 <2 7/18/84 0925 83 190 <1 3/8/85 1750 48 260 <.6 8/20/86 1000 <0.2 1/5/87 0900 49 500 0.5 4/11/88 1310 68 300 0.5



### C-lSELENIUM STREAM NETWORK SAMPLING RESULTS



### ......................................................................................................................................................................................... . .............................. RWQCB TEMP EC SELENIUM CONCENTRATIONS (ug/L) * LOCATION ID DATE TIME ( F) umhos/cm ANLAB CAL USGS DWR SDSU

----- .. -- .. --- .... -- .......................... - ...................................... -- .. - .......... - ...... ----- .............. - ....• ----------------- ...... ------- ...... COLE & KELSEY CREEKS SY·4 4/25/84 1100 60 170 <2 5/17/84 1030 65 175 <2 5/31/84 1010 73 180 <2 6/25/84 1045 74 175 <2 7/18/84 0955 83 190 <1 3/8/85 1825 49 120 <.6 8/20/86 1035 0.2 1/5/87 0940 46 185 0.3 4/11/88 1400 74 260 <0.2

MIDDLE CREEK ABOYE SY·5 4/25/84 1215 59 170 <2 CLEAR LAKE 5/17/84 1120 61 180 <2 5/31/84 1050 65 170 <2 6/25/84 1130 70 190 <2 7/18/84 1035 DRY 3/8/85 1850 50 150 <.6 8/20/86 1115 DRY 1/5/87 1020 50 230 0.4 4/11/88 1455 68 250 0.2

SCOTTS CREEK ABOVE SY·5B 4/25/84 1230 56 230 <2 CLEAR LAKE 5/17/84 1105 61 335 <2 5/31/84 1010 73 315 <2 6/25/84 1115 78 210 <2 7/18/84 1025 83 220 <1 8/20/86 1130 225 0.2 1/5/87 1010 48 570 0.5 4/11/88 1445 70 450 0.2

CACHE CREEK AT HWY 20 SV·6 5/17/84 1210 <2 5/31/84 1135 61 200 <2 <2 6/15/84 1215 60 190 <2 7/18/84 1115 58 170 <1 8/20/86 1230 215 <.2«.2) 1/5/87 1110 48 460 0.9 4/11/88 1540 66 250 0.2

STONY CREEK ABOVE SY·7 4/25/84 1500 60 280 <2 <2 BLACK BUTTE RESERYOIR 5/17/84 1400 70 240 <2 5/31/84 1330 71 260 <2 <2 6/25/84 1415 80 280 <2 7/18/84 1315 85 270 <1 3/9/85 0745 44 260 8/20/86 1430 270 0.3 10/8/86 1400 390 0.7 1/5/87 1300 52 320 1.6(1.1) 4/11/88 1740 74 300 1.0

C-2SELENIUM STREAM NETYORK SAMPLING RESULTS

.... ------------- .•. ------------------------------------------------------------- ..... --------------------------- RWQCB TEMP EC SELENIUM CONCENTRATIONS (ug/L) * LOCATION ID DATE TIME ( F) umhos/cm ANLAB CAL USGS DIIR SDSU

---------------------- .•. --------------------------- .... ---------------- .. --- .. -------- .. -- .... -- .•... -- .. - .. ------------- STONY CREEK BELOW SV-8 4/25/84 1535
. 58 300 <2 <2 BLACK BUTTE RESERVOIR 5/17/84 1430 65 260 <2 5/31/84 1400 63 260 <2 <2 6/25/84 1435 74 270 <2 7/18/84 1335 75 275 <1 3/9/85 0810 46 250 8/20/86 1500 245 0_4(0.4) 10/8/86 1515 80 390 0.8 1/5/87 1325 50 430 0.7 4/11/88 1810 64 300 0.8

KENDRICKS & SALT CREEKS SV-9 4/25/84 1600 64 500 <2 <2 ABOVE BLACK BUTTE 5/17/84 1450 76 465 <2 RESERVOIR 5/31/84 1415 78 450 <2 <2 6/25/84 1455 85 435 <2 7/18/84 1345 DRY 3/9/85 0820 45 470 8/20/86 1525 360 0.3 1/5/87 1340 54 600 0.6 4/11/88 1830 72 675 0.9

THOMES CREEK AT SV-10 4/25/84 1640 54 160 <2 <2 PASKENTA 5/17/84 1530 67 125 <2 5/31/84 1445 71 155 <2 <2 6/25/84 1530 84 220 <2 7/18/84 1410 89 250 <1 3/9/85 0845 44 145 <.6 8/20/86 1555 280 0.3 1/5/87 1405 51 220 0.6 4/11/88 1900 68 170 0.2
COTTONI/OOD CREEK AT SV-11 4/26/84 1015 54 230 <2 INTERSTATE 5 5/17/84 1700 74 175 <2 5/31/84 1600 73 180 <2 6/25/84 1630 75 150 <2 7/18/84 1500 79 140 3/9/85 0950 46 220 <.6 8/20/86 1655 150 <0.2 1/5/87 1505 50 320 1.0 4/12/88 0915 63 270 <0.2

CLEAR CREEK BELOW SV-12 4/26/84 0630 47 65 <2 IIHISKEYTOWN RESERVOIR 5/17/84 1745 60 65 <2 5/31/84 1645 62 60 <2 6/25/84 1720 66 65 <2 7/18/84 1545 65

- 60



### C-3SELENIUM STREAM NETWORK SAMPLING RESULTS

- ........................... -- .... --_ ................................. 

### _- ........•...................................... _----_ .................... ------------------_ .. _---_ .. RWQCB TEMP EC SELENIUM CONCENTRATIONS (ug/L) 

### * LOCATION ID DATE TIME ( F) umhos/cm ANLAB CAL USGS DWR SDSU

.................................................. --_ .......... ---_ ............................................ --_ ...... -_ .. -_ .... -_ .. -_ ...... -_ ............ 

### -_ .................................... CLEAR CREEK BELOW SV-12 3/9/85 1040 44 55 <.6 WHISKEYTOWN RESERVOIR 8/20/86 1740 55 0.2 1/5/87 1550 50 100 <0.2 4/12/88 0740 48 100 0.3

SPRING CREEK AT SV-13 4/26/84 0900 54 1100 <2 <2 DEBRIS DAM 5/17/84 1815 66 1200 <2 5/31/84 1710 68 1350 <2 <2 6/26/84 0935 72 1500 <2 7/18/84 1600 88 2000 3/9/85 1100 42 650 8/20/86 1845 2300 0.6 1/5/87 1610 50 1200 1.2 4/12/88 0815 55 1250 1.2

MILL CREEK AT HWY 99 SV-14 4/26/84 1115 52 110 <2 5/18/84 0700 54 100 <2 6/1/84 0655 56 80 <2 6/26/84 1130 68 105 <2 7/18/84 1725 83 125 <1 3/9/85 1230 49 110 <.6 8/21/86 0755 190 0.2 4/12/88 1010 59 160 <0.2

CHICO CREEK IN CHICO SV-15 4/26/84 1200 52 130 <2

BIG CHICO CREEK AT SV-16 4/26/84 1245 54 160 <2 RIVER ROAD 5/18/84 0810 63 200 <2 6/1/84 0735 50 115 <2 6/26/84 1220 69 105 <2 7/18/84 1815 75 100 3/9/85 1330 47 120 <.6 8/21/86 0840 105 <0.2 1/20/87 0900 0.2 4/12/88 1125 68 240 0.4

FEATHER RIVER AT EAST SV-17 4/26/84 1400 57 70 <2 GRIDLEY ROAD 5/18/84 1105 62 70 <2 6/1/84 0905 65 75 <2 6/26/84 1330 69 65 <2 7/18/84 1900 70 70 3/9/85 1430 50 60 <.6 8/21/86 0945 70 <0.2 1/6/87 0920 52 90 0.3 4/12/88 1240 63 90 0.4



### C-4SELENIUM STREAM NETWORK SAMPLING RESULTS

------------------------- ...... -- ................ --- .. ---- ...................... 

### --- ...... ----- .... --- .. -- ........ - .... --- .... 

### -- .... 

### -- ... ----- ............ - RWQCB TEMP EC SELENIUM CONCENTRATIONS (ug/L) * LOCATION ID DATE TIME ( F) umhos/cm ANLAB CAL USGS DWR SDSU

...... '" 

### ................................................................................................................................................................................................................ YUBA RIVER AT SV-18 4/26/84 1440 58 70 <2 MARYSVILLE 5/18/84 1145 56 65 <2 6/1/84 0950 55 50 <2 6/26/84 1400 64 55 <2 7/18/84 1930 65 50 <1(<1) 3/9/85 1450 50 60 <_6 8/21/86 1025 70 0.2 1/6/87 1000 52 100 0.2 4/12/88 1320 63 100 0_2

BUTTE CREEK ABOVE SV-19 4/26/84 1530 60 175 <2 <2 SACRAMENTO RIVER 5/18/84 1240 70 200 <2 6/1/84 1035 75 250 <2 <2 6/27/84 1055 <2 7/19/84 0805 79 245 <1 3/9/85 1530 51 185 <.6 8/21/86 1100 240 0.2 9/2/86 0845 74 230 0.4 1/6/87 1040 52 210 0.3 4/12/88 1430 61 160 0.3

COLUSA BASIN DRAIN AT SV-20 4/26/84 1630 59 420 <2 <2 ROAD 99E 5/18/84 1400 69 355 <2 6/1/84 1110 71 465 <2 <2 6/27/84 1200 <2 7/19/84 0900 73 360 <1 3/9/85 1640 53 200 <.6 8/21/86 1200 330 0.3(0.3) 9/2/86 1020 72 330 0.6 1/6/87 1135 900 0.7 4/12/88 1600 69 400 0.8

FEATHER RIVER AT HWY 99 SV-21 4/27/84 0930 58 80 <2 <2 5/18/84 1600 70 80 <2 6/1/84 1355 68 65 <2 <2 6/26/84 1440 74 <2 7/19/84 1015 69 70 <1 3/9/85 1800 51 60 <.6

NATOMAS EAST DRAIN AT SV-22 4/27/84 1010 57 255 <2 <2 .- ELKHORN BLVD

NATOMAS EAST DRAIN AT SV-22A 5/18/84 1635 72 330 <2 DEL PASO ROAD 6/1/84 1430 77 445 <2 <2 6/26/84 1515 86 455 <2 7/19/84 1215 77 395 <1



### C-5SELENIUM STREAM NETWORK SAMPLING RESULTS

------- - --- - ------------------- - -- - ---- - ---- - -------- - -- - ------ - ------------- - -------- - ------ - -------- - -- - -- RWQCB TEMP EC SELENIUM CONCENTRATIONS (ug/L) 

### * LOCATION ID DATE TIME ( F) umhos/cm ANLAB CAL USGS DWR SDSU

... . ...... ---------- . . . . .. -- . ...... 

### - ..... - . . .. - ......... . . . . . .. . .. . ... . ... . . . 

### --- ... . .. -- .... -- ....... ------ ..... . . . -- . . . .... ..... ---- ...... .. . . ... . - .. ------------- NATOMAS EAST DRAIN " AT SV

- 22A 3/9/85 1820 58 650 <_6 DEL PASO ROAD 8/21/86 1350 410 0.2 9/2/86 1235 76 400 0_5 1/6/87 1320 820 0.5 4/12/88 1745 65 250 1.2

AMERICAN RIVER BELOW SV-23 4/27/84 1115 54 39 <2 NIMBUS DAM
AMERICAN RIVER AT SV-23A 5/19/84 0930 55 39 <2 SUNRISE BLVD 6/1/84 1515 57 45 <2 <2 6/26/84 1600 60 37 <2 7/19/84 1250 63 32 <1 3/13/85 0735 47 31 <.6 8/21/86 1455 40 <0.2 9/2/86 1420 72 35 0.3 1/6/87 1405 60 0.2 4/11/88 0845 57 80 0.5

SACRAMENTO SLOUGH ABOVE SV-24 5/18/84 1425 72 300 <2 RD 1500 DISCHARGE 6/1/84 1225 76 260 <2 6/27/84 1230 <2 7/19/84 0920 79 300 3/9/85 1655 57 325 <.6 8/21/86 1225 290 0.2 9/2/86 1050 76 280 0.3 1/6/87 1155 320 0.4 4/12/88 1625 68 260 0.4

TOE DRAIN ABOVE SV-25 5/21/84 1040 68 340 <2 CACHE SLOUGH
RD 108 DISCHARGE SV-26 9/2/86 1000 75 450 0.4(0.6) 4/12/88 1540 74 490 0.8
FEATHER RIVER AT WEST SV-27 8/21/86 1330 70 <0.2 CATLETT ROAD 9/2/86 1200 72 70 0.4(0.8) 1/6/87 1250 120 0.4 4/12/88 1720 65 90 0.3

SUTTER BYPASS AT SV-28 9/2/86 0910 75 240 0.3 TARKE ROAD 4/12/88 1400 69 240 0.3



### * All selenium values reported as total selenium in ug/L. Laboratories conducting analyses are ANLAB (ANLAB of Sacramento), CAL (California Analytical Laboratories, Sacramento) USGS (United States Geological Survey Laboratory, Denver), DWR (California Department of Water Resour, Bryte Laboratory, Sacramento) and SDSU (South Dakota State University, Brookings). 

## () = duplicate sample 

### C-6SELENIUM STREAM NETWORK SAMPLING RESULTS CONCENTRATIONS IN THE SACRAMENTO RIVER

. ... ---- ........................ ------- ...... --------------- .. ---------- ...................... --- ....... . -- .. --- .... 

### --- .... --- ...... -- ...... - ............ - .. . . - RWQCB TEMP EC SELENIUM CONCENTRATIONS (UG/L) 

### * LOCATION 10 DATE TIME ( F) umos/cm ANLAB CAL USGS DWR SDSU

-- .... -------- .. ----- .. -- .. - ........... . ... ... . . - . . .... -- . . ....... . ..... . . . .. . . - ...... ---------------- .... --- .... -- ............ -- ...... --- .. -------- ............ BELOW KESWICK DAM SR·A 4/26/84 0720 46 390 <2 5/17/84 1830 49 100 <2 5/31/84 1720 50 100 <2 <2 6/26/84 0945 50 100 <2 7/18/84 1615 53 85 3/9/85 1110 45 80 <.6 1/6/87 1620 50 130 0.2 4/12/88 0835 48 130 <0.2

OFF RIVER ROAD ABOVE SR·B 5/18/84 0800 58 125 <2 BIG CHICO CREEK 6/1/84 0735 50 115 <2 <2 6/26/84 1210 64 100 <2 7/18/84 1805 64 95 <1(<1) 3/9/85 1315 48 100 <.6

AT HAMILTON SR·C 1/20/87 0915 0.2 4/12/88 1100 58 140 0.2

AT COLUSA SR·D 9/2/86 0820 0.2

AT GRIMES SR·E 5/18/84 1315 63 120 <2 6/1/84 1110 66 120 <2 <2 6/27/84 1115 <2 7/19/84 0830 66 105 3/9/85 1600 49 100 <.6 1/6/87 1100 120 0.4 4/12/88 1500 62 140 0.4

AT VILLAGE MARINA SR·F 9/2/86 1305 74 160 0.5 1/6/87 1330 170 0.2

AT HOOD SR·G 9/2/86 1340 75 140 1.4 1/6/87 1455 52 160 0.5(0.2) 4/11/88 1000 64 150 0.6

AT RIO VISTA BRIDGE SR·H 5/21/84 1230 66 150 <2



### * All selenium values reported as total selenium in ug/L. Laboratories conducting analyses are AN LAB (ANLAB of Sacramento), CAL (California Analytical Laboratories, Sacramento), USGS (United States Geological Survey Laboratory, Denver, DWR (California Department of Water Resources, Bryte Laboratory, Sacramento) and SDS) and SDSU (South Dakota State Univerookings). 

## () = duplicate sample



### C-7