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 1988

CALIFORNIA 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

i

SUMMARY

INTRODUCTION

SELENIUM IN THE SACRAMENTO RIVER BASIN

TABLE OF CONTENTS

PAGE

-1-

1

BASIN DESCRIPTION 2

Physical Characteristics 2

Beneficial Uses 4

Pre-1984 Water Quality Data 5

SPECIAL SURVEYS

STREAM MONITORING RESULTS 1984-89

14

12

DISCUSSION AND CONCLUSIONS 14

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

ii
LIST 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

iii
SELENIUM 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

1
found 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 Characteristics

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

2
AVERAGE 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

10

I

.Mlll.5

Figure 1

SACRAMENTO BASIN--tENTRAL VALLEY

3
Putah 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: municipal 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

4
of 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 most 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 are 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.

5
TABLE 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

6
TabLe 2. Monitoring Stations with High Average

SeLenium Concentrations as Measured

Prior to 1984.

CONCENTRATION (UG/L)

TYPE.!, SAMPLE NO. AVERAGE RANGE

PERIOD OF

LOCATION AGENCY RECORD

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.

7
Table 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

8
Table 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

9
Table 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 A0718000 American R BL Nimbus Dam DWR

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 MILES
waste 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 continuous 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 whi 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 survey,

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 River Basin

as reported in AppendixB.

1984 - 1987

r r

__"-'_.,/ -- I

J r.,'"..

\

'- 5

\

" \

-..• 28 <.

~ -....'-

~~/

1

ere",.

13 "I~t S
SPECIAL 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 Berryessa, 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 survey.

The laboratory results for the June 1984 survey were subsequently

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 0.10 mg/Kg.

In October 1986, sediment and water samples were taken from the Black

Butte Reservoir area, to verify historical data reporting selenium

levels 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 livers by the

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. Sedi.rue nt.

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 rich site(SWRCB, 1985). The second highest

valleywide concentration, 9.1 mg/Kg in rainbow trout liver was

collected in the Shasta Lake/McCloud River area. In response to high

selenium levels detected in the trout liver, grab samples were

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.

DISCUSSION AND CONCLUSIONS

Data obtained from the 1984-88 stream monitoring for total selenium in

the Sacramento River 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.

14
Table 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

15
Additional 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 one

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).

16
Table 5.

Selenium in fish tissueas reported in the SWRCB

Toxics Substances Monitoring Program for

1984, 1985, and 1986

selenium concentration (mg/Kg wet weight)!/

1984 1985 1986

Location Flesh Liver Flesh Liver Flesh Liver

9.1

i-'

-J

McCloud River/Shasta Lake

Sac River @ Shasta Dam

Sac River @ Keswick

Black Butte Reservoir

Stony Gorge Reservoir

East Park Reservoir

Rollins Reservoir

Indian Valley Reservoir

Lake Berryessa @ Pope Creek

Lake Berryessa @ Putah Creek

Lake Berryessa @ Capell Creek

Feather River @ Nicolaus

Sacramento Slough

Natomas East Main Drain

Sac River @ Clarksburg

Beach Lake

Sac River @ Hood 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 reportedby the californiaDepartmentof Fish and Game.

?:J

All values representconcentrationsin fish flesh.
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 checks 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

Quality Analyses Made for the Seepage/Drainage Investigation of Colusa

Zone of Benefit 2, November 1986. Delivery 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 Kesterson National Wildlife

Refuge and the 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 Water Resources Control Board. 1987. Toxic 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 Protocol

Two methods were used for collecting water samples for total selenium

analysiss direct collection from stream 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 plastic bottles and

preserved with acid to a pH<2.

~4hen using the bucket, water was collected from the center of a bridge on

the downs tr eam side. The bucket \'/asrinsed two times wi th sample before

final collection. The sample was then poured directly from the bucket to

the acid-washed sampling bottle. Care was taken to avoid disturbing bottom

sediments and to collect each sample as close to the center of flow as

possible.

In addition to water samples taken for total selenium analysis, field data

was collected for electrical conductivity (EC) and temperature. EC was

measured using a Myron OS Meter, model 532 MI. Standard procedures were

followed which included calibration at each site and rinsing the cell cup

three times with sample before taking the reading.

A standard Fahrenheit thermometer was used to measure temperature either by

direct placement into stream flow or into the bucket. Temperature measurements wer e taken after selenium sampling and EC analysis were completed.

In all cases, order of collection were as follows:

1. water sample for selenium analysis;

2. electrical conductivity;

3. temperature.

For each sampling run, a travel blank was prepared by filling a 6 oz.

acid-washed linear polyethylene plastic container with deionized water and

acidifying with acid to pH<2. At each site, the travel blank was opened

and placed in the vicinity during water collection for selenium analysis.

The blank Vias closed before EC and temperature measurements were taken.

Sediment

Most sediments were collected using a modified brass Eckman sampler. For

sediments collected within lakes, the Eckman was dropped from a boat and

each "s amp le ' was a composite of four collections. Each collection

consisted of approximately 100 grams from the top two inches of bottom

sediment. The sampler vias acid-washed and rinsed with surrounding surface

water between Each site.

For sediments collected in shallow streams, a modified soil auger was used.

For each site, the top two inches of bottom sediment was collected in

A-I
Append ix P.

e c id-washed two-inch PVC pipe. Six collections taken as a random transect

of the stream \"tere composited for each site sample.

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

contracted laboratory.

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.

SV-2B Putah Creek at left bank of HWY 29 bridge.

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 tream 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
10. Description

SV-12 Clear Creek below Whiskeytown Reservoir. Midstream sample dovmstream of Paige Bar Road

Bridge.

SV-13 Right bank of Spri ng Creek at Debri s Dam spi11.

SV-l~ Mill Creek at H\~Y 99 bridge. Bucket sample,

downstream side.

SV-1S Left bank of Big Chico Creek at 6th Street bridge

in Chico.

SV-16 Big Chico Creek above the Sacramento River.

Bucket sample, downstream of River Road bridge.

SV-17 Feather River near East Gridley Road. Right bank,

above bridge.

SV-IB Yuba River in Marysville. Left bank above Ramirez

Street Bridge.

SV-19 Butte Creek above Sacramento River. Bucket sample

taken from gate release we lkway off Butte Slough

Road.

SV-20 Colusa Basin Drain at Road 99E. Bucket sample,

downs tream of bri dge.

SV-21 Feather River downstr-eam of HWY 99 bridge. Left

bank.

SV-22 Natomas East Drainage Canal from Elkhorn Blvd.

Bridge. Bucket sample, upstream of bridge.

Natomas East Drainage Canal from Del Paso Road

Bridge. Bucket sample, downstream side.

SV-22,fJ,

SV-23 American River below Nimbus Fish Hatchery along

left bank.

SV-23A American River at Sunrise Blvd. foot bridge.

Bucket sample downstream side.

SV-2~ Sacramento Slough above RO 1000 discharge. Bucket

sample, downstream side of bridge.

SV-25

SV-26

Toe Drain above Cache Slough by boat.

RD 108 discharge 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 C

SELENIUM 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-l
SELENIUM 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-2
SELENIUM 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-3
SELENIUM 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-4
SELENIUM 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-5
SELENIUM 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-6
SELENIUM 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