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Cover: Photograph of coring boat preparing to deploy gravity core in Lake 

Roosevelt at site near Whitestone Mountain, Washington (Photograph taken 

by Robert Drzymkowski, U.S. Geological Survey, September 10, 2002.)

Inset 1: Retrieval of 40 centimeter sediment core including lacustrine and 

pre-reservoir soil sediments near Marcus, Washington. (Photograph taken by 

Robert Drzymkowski, U.S. Geological Survey, September 12, 2002.)

Inset 2: Sediment core collected near Rice, Washington. (Photograph taken by 

Robert Drzymkowski, U.S. Geological Survey, September 10, 2002.)

Inset 3: Scanning electron microscope (backscatter image) of slag grain. 

(Photograph taken by J. Stewart Lowther, University of Puget Sound, 2003.)
Vertical Distribution of Trace-Element 

Concentrations and Occurrence of 

Metallurgical Slag Particles in 

Accumulated Bed Sediments of 

Lake Roosevelt, Washington, 

September 2002

By Stephen E. Cox, Peter R. Bell, J. Stewart Lowther, and Peter C. VanMetre

Prepared in cooperation with the 

Confederated Tribes of the Colville Reservation

Scientific Investigations Report 2004-5090

U.S. Department of the Interior

U.S. Geological Survey
U.S. Department of the Interior

Gale A. Norton, Secretary

U.S. Geological Survey

Charles G. Groat, Director

U.S. Geological Survey, Reston, Virginia: 2005

For sale by U.S. Geological Survey, Information Services

Box 25286, Denver Federal Center

Denver, CO 80225

For more information about the USGS and its products:

Telephone: 1-888-ASK-USGS

World Wide Web: http://www.usgs.gov/

Any use of trade, product, or firm names in this publication is for descriptive purposes only and does not imply 

endorsement by the U.S. Government.

Although this report is in the public domain, permission must be secured from the individual copyright owners to 

reproduce any copyrighted materials contained within this report.

Suggested citation:

Cox, S.E., Bell, P.R., Lowther, J.S., and VanMetre, P.C., 2005, Vertical distribution of trace-element concentrations and 

occurrence of metallurgical slag particles in accumulated bed sediments of Lake Roosevelt, Washington, September 

2002: U.S. Geological Survey Scientific Investigations Report 2004-5090, 70 p. 
iii

Contents

Abstract ................................................................................................... 1

Introduction ................................................................................................ 1

Purpose and Scope ................................................................................. 2

Description of Study Area ........................................................................ 2

Previous Studies of Trace Elements in Lake Roosevelt Bed Sediments ..................... 5

Acknowledgments ................................................................................. 7

Data Collection and Analysis ........................................................................... 7

Sample Collection and Processing ............................................................... 8

Isolation and Identification of Slag Particles ................................................... 9

Accumulated Sediments in Lake Roosevelt ............................................................ 10

Description of Cores and Accumulated Sediments .......................................... 10

Cesium-137 Concentrations and Rates of Sediment Accumulation ........................... 10

Assignment of Time Stratigraphic Horizons ................................................ 10

Sedimentation Rates ........................................................................ 13

Concentrations of Trace Elements in Accumulated Sediments .............................. 14

Trace-Element Profiles ........................................................................... 15

Patterns of Trace-Element Profiles Within Individual Cores ................................. 24

Trace Elements in Pore Water and Sediment ......................................................... 31

Metallurgical Slag in Sediments of Lake Roosevelt ................................................... 34

Relative Impacts of Slag and Liquid Effluent Discharge on Trace-Element 

Concentrations in Bed Sediment .................................................................. 46

Summary and Conclusions .............................................................................. 47

References Cited .......................................................................................... 48

Figures

 Figure 1. Map showing location of study area and sediment-core collection sites 

on Lake Roosevelt and the upper Columbia River, Washington ........................ 3

 Figure 2. Boxplots showing concentrations of selected trace elements in suspended 

sediment from the Columbia River at Northport, Washington, and in Lake 

Roosevelt shoreline bank materials ...................................................... 4

 Figure 3. Profiles showing vertical distribution of cesium-137 concentrations in 

sediment cores from Lake Roosevelt, Washington, September 2002 ............... 12

 Figure 4. Profiles showing vertical distribution of trace-element concentrations in 

selected sediment cores from Lake Roosevelt, Washington, September 2002 ...... 16

 Figure 5. Graph showing ratios of cadmium to mercury and zinc to lead in samples 

from sediment cores from Lake Roosevelt, Washington, September 2002 ......... 23

 Figure 6. Profiles showing vertical distribution of trace-element concentrations in six 

sediment cores from Lake Roosevelt, Washington, September 2002 ............... 24

 Figure 7. Graph showing history of slag and trace elements in liquid effluent discharged 

to Columbia River by Trail smelter, British Columbia, 1940-2000 ..................... 30
iv

 Figure 8. Profiles showing vertical distribution of concentrations of dissolved arsenic, 

cadmium, copper, lead, and zinc in pore waters from sediment core sampling 

sites CCR-668, CCR-692, and CCR-705, Lake Roosevelt, Washington .................. 32

 Figure 9. Graphs showing concentrations of arsenic, cadmium, copper, lead, and zinc 

in whole sediment and leached residual (following extraction with hydroxylamine 

hydrochloride) from sediment core sampling sites CCR-668 and CCR-705, 

Lake Roosevelt, Washington, July 2003 ................................................... 33

 Figure 10. Photograph showing black sand beach composed of 70 to 90 percent slag 

particles deposited near Columbia River gaging station at river mile 743, 

Washington ................................................................................. 35

 Figure 11. Photographs showing slag particles (RS-743) identified in sediment from Lake 

Roosevelt and the upper Columbia River, Washington ................................. 36

 Figure 12. Photographs showing scanning electron microscope (backscatter images) 

of unweathered slag particles from Lake Roosevelt, Washington .................. 38

 Figure 13. Boxplots showing trace-element concentrations determined by SEM/EDS of 

slag particle (sample RSS-743) and reported concentrations from previous 

studies determined by acid digestion and instrumental analysis, Lake Roosevelt, 

Washington ................................................................................. 40

 Figure 14. Boxplot showing trace-element concentrations determined by SEM/EDS of 

recently deposited slag particles and slag grains from core sediments, Lake 

Roosevelt, Washington ..................................................................... 41

 Figure 15. Photographs showing scanning electron microscopic (backscatter images) 

of weathered slag particles from Lake Roosevelt, Washington ..................... 42

 Figure 16. Boxplot showing trace-element concentrations determined by SEM/EDS of 

outer surface of slag particles and inner surface exposed by removal of 

exfoliation flake, Lake Roosevelt, Washington .......................................... 45

Tables

 Table 1. Comparison of mean (N=3) element concentrations in riverbed sediments 

from upstream and downstream of the smelter at Trail, British Columbia, 1995 

and 1999 ....................................................................................... 7

 Table 2. Location and depth of six sediment cores and samples of riverine sediment 

with slag from Lake Roosevelt, Washington, September 10–13, 2002 ............... 8

 Table 3. Time horizons and sediment accumulation rates for six cores from Lake 

Roosevelt, Washington ..................................................................... 13

 Table 4. Summary of concentrations of arsenic, cadmium, copper, lead, mercury, and 

zinc in all analyzed core subsections from Lake Roosevelt, Washington ............ 14

 Table 5. Vertical distribution of major and trace-element concentrations in sediment 

core subsections from Lake Roosevelt, Washington, September 2002 ............... 51

 Table 6. Analytical results for standard reference material and environmental duplicate 

samples for quality assurance ............................................................ 63

 Table 7. Vertical distribution of concentrations of selected trace elements and major 

ions in pore water, bulk sediment, and residual sediment from shallow cores 

from sites CCR-668, CCR-692, and CCR-705, Lake Roosevelt, Washington, 

July 2003 .................................................................................... 66
v

Conversion Factors, Datums, Abbreviations, 

and Acronyms

Conversion Factors

Multiply By To obtain

centimeter (cm) 0.3937 inch

cubic meter (m3) 264.2 gallon

gram (g) 0.03527 ounce, avoirdupois

gram per cubic centimeter (g/cm3) 64,4220 pound per cubic foot

hectare (ha) 2.471 foot

kilogam (kg) 2.205 pound, avoirdupois

meter (m) 3.281 foot

metric ton per day 1.102 ton per day

mile (mi) 1.609 kilometer

millimeter (mm) 0.03937 inch

tonnes (1,000 kg) 1.102 ton (2,000 lbs)

Temperature in degrees Celsius (°C) may be converted to degrees Fahrenheit (°F) as follows:

 °F=(1.8×°C)+32.

Datums

Vertical coordinate information is referenced to the National Geodetic Vertical Datum of 1929 

(NGVD 29).

Horizontal coordinate information is referenced to the North American Datum of 1927 (NAD27).

Abbreviations

Abbreviations Meaning

M Molar

mg/kg milligram per kilogram

mL milliliter

pCi/g picoCuries per gram

Acronyms

Acronyms Meaning

CCT Confederated Tribes of the Colville Reservation

USGS U.S. Geological Survey
vi

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Abstract

Sediment cores were collected from six locations in 

Lake Roosevelt to determine the vertical distributions of 

trace-element concentrations in the accumulated sediments of 

Lake Roosevelt. Elevated concentrations of arsenic, cadmium, 

copper, lead, mercury, and zinc occurred throughout much 

of the accumulated sediments. Concentrations varied greatly 

within the sediment core profiles, often covering a range of 

5 to 10 fold. Trace-element concentrations typically were 

largest below the surficial sediments in the lower one-half of 

each profile, with generally decreasing concentrations from 

the 1964 horizon to the surface of the core. The trace-element 

profiles reflect changes in historical discharges of trace 

elements to the Columbia River by an upstream smelter. 

All samples analyzed exceeded clean-up guidelines 

adopted by the Confederated Tribes of the Colville 

Reservation for cadmium, lead, and zinc and more than 

70 percent of the samples exceeded cleanup guidelines for 

mercury, arsenic, and copper. Although 100 percent of the 

samples exceeded sediment guidelines for cadmium, lead, and 

zinc, surficial concentrations of arsenic, copper, and mercury 

in some cores were less than the sediment-quality guidelines. 

With the exception of copper, the trace-element profiles of the 

five cores collected along the pre-reservoir Columbia River 

channel typically showed trends of decreasing concentrations 

in sediments deposited after the 1964 time horizon. The 

decreasing concentrations of trace elements in the upper half 

of cores from along the pre-reservoir Columbia River showed 

a pattern of decreasing concentrations similar to reductions 

in trace-element loading in liquid effluent from an upstream 

smelter. Except for arsenic, trace-element concentrations 

typically were smaller at downstream reservoir locations along 

the pre-reservoir Columbia River. Trace-element concentration 

in sediments from the Spokane Arm of the reservoir showed 

distinct differences compared to the similarities observed in 

cores from along the pre-reservoir Columbia River. 

Particles of slag, which have physical and chemical 

characteristics of slag discharged to the Columbia River by 

a lead-zinc smelter upstream of the reservoir at Trail, British 

Columbia, were found in sediments of Lake Roosevelt. 

Slag particles are more common in the upstream reaches 

of the reservoir. The chemical composition of the interior 

matrix of slag collected from Lake Roosevelt closely 

approximated the reported elemental concentrations of fresh 

smelter slag, although evidence of slag weathering was 

observed. Exfoliation flakes were observed on the surface 

of weathered slag particles isolated from the core sediments. 

The concentrations of zinc on the exposed surface of slag 

grains were smaller than concentrations on interior surfaces. 

Weathering rinds also were observed in the cross section of 

weathered slag grains, indicating that the glassy slag material 

was undergoing hydration and chemical weathering. 

Trace elements observed in accumulated sediments in the 

middle and lower reaches of the reservoir are more likely due 

to the input from liquid effluent discharges compared to slag 

discharges from the upstream smelter.

Introduction

Trace-element contamination is known to be widespread 

throughout surficial bed sediments of Franklin D. Roosevelt 

Lake, the reservoir created by the impoundment of the 

Columbia River behind Grand Coulee Dam. Franklin D. 

Roosevelt Lake, better known as Lake Roosevelt, was 

completed in 1941 and has developed into a major economic 

and recreational resource for the region attracting from 1 to 

1.5 million visitors each year. Lake Roosevelt also is a vital 

cultural resource for The Confederated Tribes of the Colville 

Reservation (CCT) and The Spokane Tribe of Indians whose 

combined tribal lands extend along more than one-half of the 

reservoir’s length. The reservoir is used extensively by many 

tribal members who live near the reservoir.

Vertical Distribution of Trace-Element Concentrations 

and Occurrence of Metallurgical Slag Particles in 

Accumulated Bed Sediments of Lake Roosevelt, 

Washington, September 2002

By Stephen E. Cox, Peter B. Bell, J. Stewart Lowther, and Peter C. VanMetre
Trace-element contamination of reservoir sediments 

was first reported in the mid-1980s (Lowe and others, 

1985; Johnson and others, 1988, 1990). Trace elements of 

concern include arsenic, cadmium, copper, lead, mercury, 

and zinc. Subsequent studies have shown that trace-element 

contamination of surficial sediments in the lake and adjacent 

beach deposits is widespread and follows a general pattern 

in which concentrations of trace elements typically are 

larger in the upstream reaches of the reservoir compared to 

concentrations in downstream reaches (Johnson and others, 

1990; Bortleson and others, 1994; Majewski and others, 2003; 

U.S. Environmental Protection Agency, 2003). Trace-element 

concentrations in bed sediments range from 4 to 220 times 

larger than concentrations in background reference sediments. 

In addition, contamination of sport fish with mercury and 

other trace elements has resulted in the issuance of a health 

advisory on the human consumption of several species of 

popular sport fish (Munn and others, 1995), although the 

level of sport fish contamination has decreased for some 

constituents (Munn, 2000). 

The primary source of elevated trace-element 

concentrations in bed sediments of Lake Roosevelt is 

attributed to the transport of metallurgical wastes discharged 

to the Columbia River by a smelter at Trail, British Columbia, 

located 21 km upstream of the International Boundary 

(Bortleson and others, 1994). The smelter has been in 

operation since the 1890s and historically has discharged 

wastes to the Columbia River, much of which are transported 

and deposited in the quiescent waters of Lake Roosevelt. 

Although waste discharges have occurred nearly continuously 

throughout most of Lake Roosevelt’s 60 plus years of 

existence, efforts have been underway at the smelter over the 

last several decades to reduce trace-element loading to the 

Columbia River. The reduction in effluent discharges may 

be reflected in the variations in the concentrations of trace 

elements present in the accumulated sedimentary record of 

Lake Roosevelt. Previous information on variations in the 

vertical distribution of trace elements in the accumulated 

sediments of Lake Roosevelt is limited. Additional 

information on variations in concentrations of trace elements 

in the accumulated sediments could provide a useful record of 

trace elements entering Lake Roosevelt.

Purpose and Scope

The purpose of this report is to present the results of a 

study (1) to evaluate the trace-element concentrations within 

the accumulated bed sediments of Lake Roosevelt; (2) to 

determine if the potential exists for remobilization of trace 

elements within the buried sediments; and (3) to evaluate 

sediment from selected core intervals for the occurrence 

of metallurgical slag. The study was conducted by the 

U.S. Geological Survey (USGS) in cooperation with the 

Confederated Tribes of the Colville Reservation. Sediment 

cores were collected for the determination of trace-element 

profiles at six widely spaced locations in Lake Roosevelt in 

September 2002; with additional sediments collected in July 

2003 for analysis of trace elements in pore water. Sediment 

cores were sectioned and concentrations of trace elements 

were analyzed for the individual sections, generating a profile 

of trace-element concentrations. Selected sediment intervals 

also were examined for either the occurrence of metallurgical 

slag particles or the concentration of trace elements in pore 

water.

Description of Study Area

Lake Roosevelt is in north-central Washington and is 

the largest reservoir in the State of Washington (fig. 1). The 

lake was formed by the impoundment of the Columbia River 

behind Grand Coulee Dam and, when filled to capacity, the 

reservoir extends upstream more than 237 km such that backwater conditions extend to near the International Boundary 

(Ray Smith, U.S. Geological Survey, oral commun., 2004). 

The entire reservoir covers about 32,700 ha and has a storage 

volume of about 12.8 billion m3. The maximum water depth in 

the reservoir is more than 115 m (377 ft), and averages about 

35 m (115 ft). Flow from the Columbia River makes up the 

majority (90 percent) of the inflow to Lake Roosevelt; with 

another 7 percent of inflow from the Spokane River. Flow 

in these rivers is highly regulated and depleted of suspended 

sediment by the numerous dams and reservoirs that have 

been constructed on upstream reaches. Other sources of river 

inflow to Lake Roosevelt include the Colville, Kettle, and 

Sanpoil Rivers and the numerous creeks that drain the uplands 

surrounding the reservoir. 

Bed sediments of Lake Roosevelt vary from armored 

boulders to silts and clay. To provide a framework for 

interpreting the sediment chemistry data, Bortleson and 

others (1994) divided the reservoir along the length 

of the pre-reservoir river channel into several reaches 

based predominantly on the physical characteristic and 

depositional environment. The lower reach extends from 

Grand Coulee Dam to the confluence of the Spokane River 

and is characterized by a deep wide channel with slowing 

flowing water covering extensive pre-reservoir shorelands 

and containing lacustrine sediments, which are influenced by 

inputs from the Spokane River. The mid-reach of the reservoir 

extends from the confluence of the Spokane River to Marcus 

Island and is characterized by deep-slowing moving water in 

a wide irregular channel containing lacustrine sediments. The 

upper reach of the reservoir extends from Marcus Island to 

about RM 730, which is characterized by a narrowing and 

shallowing channel with fewer embayments and flooded 

areas generally lacking lacustrine sediments from the swifter 

flowing reservoir conditions in the pre-reservoir channel. The 

transitional reach (Northport Reach) that extends from RM 

730 to near the International Boundary where flow conditions 

transition from impounded slack water of the upper reach of 

the reservoir to the swift river environment of the free flowing 

Columbia River contain primarily a cobbly-boulder streambed 

with sand-size sediments deposited only in protected areas. 

2 Vertical Distribution of Trace Elements and Metallurgical Slag in Sediments, Lake Roosevelt, Washington, 2002
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Figure 1. Location of study area and sediment-core collection sites on Lake Roosevelt and the upper Columbia River, Washington.

Introduction 3
Sediments deposited in Lake Roosevelt are derived from 

the upper basin of the Columbia River, tributary streams and 

rivers, and from landslides and erosion of unconsolidated 

sediments along the margin of the reservoir. Granulated 

slag discharged to the Columbia River from the smelter 

upstream of Lake Roosevelt is a component of sediment that 

is transported and deposited in Lake Roosevelt. Numerous 

landslides have occurred along the shores of Lake Roosevelt, 

primarily in the unconsolidated Pleistocene terrace sediments 

that occur along 80 to 90 percent of reservoir shoreline 

(Jones and others, 1961; Kiver and Stradling, 1995; and U.S. 

Bureau of Reclamation, 2001). Large landslides on the order 

of 765,000 m3 of material occurred more frequently in the 

past, particularly in the early years following completion of 

the reservoir. Between 1941 and 1954, there were more than 

500 landslides along the reservoir shoreline that related to the 

initial filling of the reservoir and the fluctuating water level 

in the reservoir (Jones and others, 1961). Landslides continue 

to occur up to the present (U.S. Bureau of Reclamation, 

2001), although they typically are smaller in magnitude and 

the severity has greatly diminished. Concentrations of trace 

elements in bank sediments prone to landslides are on the 

order of western continental averages reported by Shacklette 

and Boerngen (1984).

Trace-element concentrations in bank material typically 

were much smaller than concentrations measured in 

suspended sediment flowing into Lake Roosevelt (Bortleson 

and others, 1994; Kelly and others, 2001). A comparison of 

trace-element concentrations in bank sediments adjacent to 

Lake Roosevelt to trace-element concentrations reported in 

Columbia River suspended sediment is shown in figure 2. 

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Figure 2. Concentrations of selected trace elements in suspended sediment from the Columbia River at Northport, Washington, and in 

Lake Roosevelt shoreline bank materials.

4 Vertical Distribution of Trace Elements and Metallurgical Slag in Sediments, Lake Roosevelt, Washington, 2002
The reported concentrations of trace elements in suspended 

sediment were determined from 22 discharge-weighted 

samples collected between 1995 and 2000 at Northport 

(Kelly and others, 2001). For the trace elements of concern, 

the greatest difference was in the concentration for zinc, 

which was roughly 30 times larger in suspended sediment 

than in bank sediments. Concentrations of cadmium, copper, 

and lead were about 10 times larger in suspended-sediment 

samples than concentrations in samples of bank sediments. 

The concentrations of arsenic were the most similar; the 

concentration in suspended sediment was only about two 

times as large as arsenic concentrations in samples of bank 

sediments. Mercury concentrations in suspended sediment 

were not reported by Kelly and others (2001), however, 

Bortleson and others (1994) reported a median concentration 

of mercury in five discharge-weighted suspended-sediment 

samples of 1.7 mg/kg, which is roughly 30 times larger than 

the concentrations in typical bank deposits (<0.05 mg/kg). 

From these data, the episodic addition of bank sediments to 

relatively consistent input of suspended sediment transported 

to Lake Roosevelt by the Columbia River will dilute the 

concentration of trace elements in the resulting bed sediments. 

Thus landslides, particularly in the upper part of the reservoir, 

tend to dilute concentrations of arsenic, copper, cadmium, 

lead, mercury, and zinc in sediments carried to the reservoir by 

the Columbia River. 

Most of Lake Roosevelt is situated within the Okanogan 

Highland of north-central Washington, an area that extends 

about 250 km north into British Columbia, in which extensive 

geologic processes have resulted in a mountainous and 

highly mineralized region containing many precious and base 

metal deposits (Washington State Department of Natural 

Resources, 2003). Geologically, this region is composed of 

some of the oldest and most mineralized geologic units in 

Washington. In the area east of Lake Roosevelt, the repeated 

folded metasedimentary rocks of the Kootenay Arc contain 

hydrothermal ore deposits, particularly lead and zinc, many 

of which have been developed. Lead and zinc ores typically 

occur as the minerals galena and sphalerite that were deposited 

in veins, open space fillings, or as replacement bodies in 

limestone and dolomite deposits. Mills (1977) describes 98 

separate deposits in Stevens County alone, many of which 

also were reported to contain minor amounts of silver. 

Numerous similar sites also occur in the Kootenay Arc region 

of British Columbia although the Sullivan Mine that produced 

much of the ore for the Trail smelter was characterized as a 

sedimentary-exhalative deposit (Lydon, 2000). Other trace 

elements often associated with lead deposits composed 

of galena include antimony, copper, arsenic, and bismuth; 

elements associated with zinc deposits composed primarily 

of sphalerite include copper, tin, arsenic, silver, mercury, 

iron, manganese, and cadmium (Levinson, 1974). Precious 

metal deposits to the west of Lake Roosevelt also have been 

developed particularly in the area around Republic. In addition 

to gold and silver, there are deposits containing copper, cobalt, 

bismuth, and molybdenum. 

Metallurgical and mining wastes have been discharged 

to streams of the upper Columbia River (Orlob and Saxton, 

1950). The Trail smelter was originally built as a copper 

smelter in 1896 and was converted to smelt lead and zinc in 

1909 (G3 Consulting, Ltd., 2001). Lead and zinc production 

have been nearly continuous since that time and the facility 

has developed into one of the worlds largest integrated 

metallurgical complexes. Annual production in 2000 was 

273,000 metric tonnes of refined zinc and 91,000 tonnes 

of refined lead, with smaller quantities of silver, gold, 

cadmium, bismuth, and many other associated metal products 

(Teck-Cominco, 2002). Historically, waste materials from 

this facility, including slag and process waste water, were 

discharged directly to the Columbia River. Between the 

late 1970s and late 1990, the metallurgical complex was 

extensively modernized to improve production efficiency and 

reduce the discharge of slag and effluent to the Columbia 

River. Effluent treatment was installed in 1981 and was 

upgraded through the 1990s. The operation of the phosphate 

fertilizer plant was discontinued in 1994. The routine 

discharge of slag to the Columbia River was discontinued in 

1995 after which time reported slag discharge has been limited 

to periods when disruption in the smelting process have 

resulted in upset conditions at the smelter when the release of 

waste material has occurred.

Previous Studies of Trace Elements in Lake 

Roosevelt Bed Sediments

Initial assessment of the extent of trace-element 

contamination in Lake Roosevelt bed sediment (Johnson and 

others, 1988, 1990) showed that elevated concentrations of 

trace elements were widespread throughout Lake Roosevelt 

and that the concentrations of trace elements decreased 

along the longitudinal axis from upstream to downstream. 

They attributed the source of the elevated trace elements 

to the discharge of smelter wastes to the Columbia River 

at Trail. This source had been previously identified by 

British Columbia Ministry of Environment (1976, 1979) 

and Environment Canada (Sheehan and Lamb, 1987; Sigma 

Engineering Ltd., 1987; and Smith, 1987; NORECOL 

Environmental Consultants Ltd., 1989,) as a source of metals 

contamination of water, sediment, and biota in the reach of 

the Columbia River immediately upstream of the International 

Border. 

A comprehensive follow-up study was conducted in 

1992 by the U.S. Geological Survey (Bortleson and others, 

1994) that determined trace-element concentrations in 

sediment from Lake Roosevelt and its tributaries, including the 

upstream reach of the Columbia River extending to reservoirs 

in Canada. The results of that study confirmed and greatly 

extended previous findings and conclusions. The overarching 

conclusion was that although other possible sources of trace 

elements were present within the region and may have a 

localized influence on trace-element concentrations in the 

sediments of Lake Roosevelt, the primary source of the 

Introduction 5
widespread elevated trace-element concentrations in the bed 

sediments of Lake Roosevelt was the waste discharged to the 

Columbia River from the Trail smelter. This conclusion, based 

on the distribution of elevated trace-element concentrations in 

bed sediments and the hydrology of the reservoir-river system, 

was the only adequate explanation of the persistent and 

widespread distribution of trace elements in the bed sediments 

throughout Lake Roosevelt and the upstream reach of the 

Columbia River and the differences in the patterns of specific 

trace-element concentrations. 

All trace elements of concern, including arsenic, 

cadmium, copper, lead, mercury, and zinc, are known to 

be components of the liquid effluent or slag discharged to 

the Columbia River by the Trail smelter (British Columbia 

Ministry of Environment, 1976; 1979). The concentrations 

of these trace elements in bed sediments were all highly 

elevated at locations downstream of the area of smelter waste 

discharge, however, the distributional pattern of elevated 

trace elements in the sediments of Lake Roosevelt varied 

among trace elements reflecting depositional grain-size 

and mode of trace-element input. The most notable pattern 

was simultaneous presence of slag particles and very large 

concentrations of copper and zinc in bed sediments of the 

upper and transitional reaches of Lake Roosevelt and the 

upstream reach of the Columbia River. Slag, which was 

reported to contain 0.5 to 1 percent copper and 2 to 3 percent 

zinc, could be easily identified in sand-size fractions by its 

unique morphology and physical characteristics. In sediment 

samples from the International Boundary, in which slag was 

estimated to compose 48 percent of sediment grains, the 

concentrations of copper and zinc were 3,000 and 15,000 

mg/kg, respectively, while slag in bed sediments 24 km farther 

downstream was estimated to comprise 5 percent of the sandsized fraction and the concentrations of copper and zinc were 

670 and 4,100 mg/kg, respectively. In the transitional reach 

of the reservoir near Northport, bed sediments contained 

substantial percentages of sand-sized particles and the very 

large concentrations of copper and zinc were attributed to 

the presence of slag particles in these sediments. Other trace 

elements noted to follow distributional patterns similar to 

slag were antimony, arsenic, barium, chromium, iron, and 

manganese.

Bortleson and others (1994) also reported that 

concentrations of cadmium, lead, and mercury were 

larger in bed sediments farther downstream in the mid and 

lower reaches of the reservoir where depositional areas 

are predominated by silt-size particles. Cadmium, lead, 

and particularly mercury are present in slag in very small 

concentrations compared to copper and zinc but are prevalent 

in the liquid effluent discharged by the Trail smelter. The 

presence of these trace elements in bed sediments of Lake 

Roosevelt was attributed to the sorption of trace elements 

from the water column onto suspended-sediment particles, 

which are subsequently deposited in the downstream quiescent 

waters of the mid and lower reaches of Lake Roosevelt. 

Because sorption is related to the surface area of particles, 

a proportionally greater mass of trace elements is sorbed to 

smaller sized sediment particles. Thus, concentrations of these 

trace elements were larger in the downstream reaches of Lake 

Roosevelt that were dominated by fine colloidal silt and clay 

sized lacustrine sediments.

Additional information on previous studies of the water 

quality of Lake Roosevelt and trace-element contamination 

of bed sediments in Lake Roosevelt have been reviewed 

and summarized in Derewetzky and others (1994) and U.S. 

Environmental Protection Agency (2000; 2003).

The effects of the Trail-smelter discharge on water, 

sediment, and biota in the Columbia River receiving water 

was evaluated in a study conducted by the smelter between 

1995 and 1999 (G3 Consulting, Ltd., 2001). The intent of that 

study was to document the effects from modernization of the 

smelter process and improved waste-management practices 

implemented in the mid-1990s on trace-element loading to 

the Columbia River from the Trail smelter effluent discharge. 

This study examined trace-element concentrations in water, 

sediment, and biota at locations upstream and downstream of 

the effluent discharge zone of the Trail-smelter complex in the 

spring and autumn of 1995 and 1999 (G3 Consulting, Ltd., 

2001). Results from this study clearly demonstrated the large 

influence that slag and liquid effluent discharges have had on 

the trace-element concentrations in water and sediment of the 

Columbia River, and thus Lake Roosevelt. 

Very large increases in trace-element concentration in 

sediment immediately downstream of the effluent and slag 

discharge from the smelter were observed during the 1995 

sampling prior to completion of the last phases of an extensive 

modernization of the lead smelting facility. As shown in 

table 1, the measured concentrations of nearly all 29 trace 

elements measured were often many fold higher in bedsediment samples collected downstream of the smelter 

complex than the concentrations measured in samples of 

similar material collected from a background reference site 

8 km upstream of the smelter complex. Although the 

measured concentrations of trace elements in sediment 

collected at the upstream reference site did not change 

substantially between 1995 and 1999, except for iron, 

the trace-element concentrations in sediments at sites 

downstream of the metallurgical complex were much smaller 

in 1999 than in 1995. These decreases in concentrations were 

attributed to implementation of the new lead smelter and 

discontinuing the practice of discharging slag to the Columbia 

River (G3 Consulting, Ltd., 2001). Considering that historical 

discharges of slag and liquid effluent were substantially larger 

than occurred in 1995, these results demonstrate a minimum 

level of influence that Trail smelter discharge had on sediment 

chemistry in the Columbia River down stream of smelter and 

subsequently Lake Roosevelt throughout most of its existence.

6 Vertical Distribution of Trace Elements and Metallurgical Slag in Sediments, Lake Roosevelt, Washington, 2002
Table 1. Comparison of mean (N=3) element concentrations in riverbed 

sediments from upstream and downstream of the smelter at Trail, British 

Columbia, 1995 and 1999.

[Modified from Appendix 3.1.4, G3 Consulting Ltd., 2001. mg/kg, milligram 

per kilogram]

Element

Upstream

reference site

Downstream

monitoring site

1995 1999 1995 1999

Major element (mg/kg)

 Aluminum 2,820 3,290 15,700 8,600

 Calcium 1,690 1,840 49,800 21,800

 Iron 5,160 14,900 181,000 80,000

 Magnesium 2,020 1,850 5,700 3,580

 Manganese 129 146 4,840 1,870

 Titanium 281 298 1,230 641

Trace elements (mg/kg)

 Antimony 0.15 0.187 56 87.2

 Arsenic 1.14 1 41.8 23.5

 Barium 29.4 24.6 3,260 920

 Berylium <.2 .14 1.4 4

 Bismuth .05 .055 .838 .218

 Boron 6.47 5 147 24

 Cadmium .17 .147 4.1 1.19

 Chromium 8.73 16.6 265 58.6

 Cobalt 2.43 2.51 192 35.6

 Copper 10.1 13.2 3,740 1,100

 Germanium <.1 .09 34.5 9.6

 Gallium 1.55 2.22 35.3 10.2

 Indium <.05 .02 23.9 9.23

 Lead 8.48 8.29 312 237

 Lithium 7.72 5.21 21.3 7.67

 Mercury <.05 <.02 .05 .02

 Molybdenum .21 .15 68.8 16.1

 Nickel 7.05 7.3 26.4 12.9

 Selenium <1 <.05 1.3 1

 Silver .12 .076 12.7 5.48

 Strontium 22.5 22.8 732 195

 Tellerium <.2 <.01 .261 .06

 Thalium <.05 .04 .353 .215

Thorium 4.04 8.81 4.38 4.22

Tin .24 .248 44 68.7

 Tungsten .59 .24 20 4.16

 Uranium .49 .68 7.16 2.34

 Vanadium 13.3 28.7 54.5 28

 Zinc 58.1 40.3 21,400 5,660

Acknowledgments

This study was conducted with the assistance of many 

individuals and organizations. We thank Patti Bailey and the 

Confederated Tribes of the Colville Indian Reservation for 

their assistance in planning and conducting this study; Greg 

Behrans of the U.S. Bureau of Reclamation at Grand Coulee 

Dam for map coverages and information on landslides; 

Brian Hicks of the Colville Tribe and Louis Wynn of the 

Spokane Tribe for archaeological support of field activities; 

Rick Sanzalone of the U.S. Geological Survey, Geologic 

Materials Laboratory for conducting the partial extraction 

of trace-element experiment and oversight of laboratory 

analysis. Technical review of previous drafts of this report 

were provided by Don Hurst of the Confederated Tribes of 

the Colville Indian Reservation and Lauri Balistrieri, Gilbert 

Bortleson (retired), Anthony Paulson, and Gary Turney of the 

U.S. Geological Survey. 

Data Collection and Analysis

Sediment cores were collected from near the pre-reservoir 

river channel where the accumulation of reservoir sediment 

was thought to be thickest and least likely to be disturbed 

by the seasonal fluctuation in water level in the reservoir. 

Other considerations for site selection included avoiding the 

presence of large landslides along the margins of the reservoir 

and consultations with tribal archaeologists to avoid possible 

disturbances of submerged ancestral tribal areas. Lacustrine 

sediments were not found in pre-reservoir channel at the 

most upstream site, consequently, the core for this area was 

collected away from the pre-reservoir channel toward the left 

bank of the reservoir on what is likely a submerged terrace. 

Five sediment cores were collected from the lower 

and mid reaches of the reservoir and one sediment core was 

collected from the Spokane Arm of the reservoir. The locations 

of these sediment cores were determined using a Global 

Positioning System (GPS) to determine latitude and longitude 

(table 2) and are shown in figure 1. Core designations were 

assigned using the nearest river mile (RM). Cores collected 

along the pre-reservoir Columbia River channel include 

CCR-624 in the lower reach of the reservoir, and CCR-643, 

CCR-668, CCR-692, and CCR-705 in the mid-reach of the 

reservoir. Core CSA-8 was collected from the Spokane Arm 

of the reservoir. Sites of continuously accumulating sediments 

Data Collection and Analysis 7
could not be identified in the upper and Northport reaches of 

the reservoir. The three most upstream cores were in areas 

where previously reported concentrations of trace elements 

typically were high. These sediment cores were selected to 

determine if the concentrations of trace elements varied within 

the accumulated sediments of Lake Roosevelt. The other 

three sediment cores were collected farther downstream in 

the reservoir to determine if sediment concentrations might 

indicate the combined influence of inflow from both the 

Columbia and Spokane Rivers. These cores were collected 

from: (1) in the Spokane Arm of the reservoir outside of 

the general influence of inflow from the Columbia River 

(CSA-8), (2) in the mainstem of the reservoir upstream of 

the confluence with the Spokane Arm (CCR-643), and (3) 

downstream of the confluence of the Spokane Arm and the 

mainstem Columbia River (CCR-624). 

Sediment samples with readily identifiable slag particles 

were collected at three sites, designated RSS-685, RSS-724, 

and RSS-743 (table 2 and fig. 1). Slag particles from these 

samples were used to characterize slag particles in Lake 

Roosevelt. Sediments in samples from the RSS-724 and RSS743 sites were collected from beach deposits immediately 

adjacent to the reservoir and the Columbia River. Sediments 

in samples from the RSS-685 site were collected from beneath 

the reservoir sediments at a site where attempts to collect 

a sediment core to determine trace-element profiles was 

unsuccessful as less than 20 cm of lacustrine sediments were 

recovered. The slag containing sand underlying the lacustrine 

silts were interpreted to be a fluvial deposit of the prereservoir Columbia River. 

Sediment cores used to develop trace-element profiles 

were collected using a Benthos gravity core with a diameter of 

6.5 cm. The gravity core was suspended from a pontoon boat 

capable of collecting cores from depths as much as 120 m. 

The gravity cores were collected in September 2002. Because 

pore water could not be obtained from the gravity cores as 

originally planned, resampling of the three upstream sites was 

conducted in July 2003 using a box core with a 14×14-cm 

cross section. GPS coordinates were used to locate the original 

sampling sites. 

Sample Collection and Processing

At each site where gravity cores were collected, several 

attempts were made to obtain undisturbed cores greater than 

50 cm in length and that also encountered the pre-reservoir 

sediments. The least disturbed core with the greatest thickness 

of lacustrine sediments was selected for subsampling and 

analysis (fig. 1 and table 2). After collection, cores were 

subsampled by pushing the top of the core up through the 

plastic core liner and slicing the core into sections that 

were 2 to 5 cm thick. Sediment samples were packed on 

Core and 

riverine 

sediment 

sample 

designation

Length of core 

(cm)

Latitude

(

o ‘ “)

Longitude

(

o ‘ “)

Depth of 

water

(m)

Elevation of

 upper surface 

of core

(ft)

Length of 

subsection 

interval 

(cm)

Number 

of subsection 

intervals

Core along Impounded Columbia River

CCR-624 46 47 53 42 118 32 27 87.5 998 3 16

CCR-643 57 47 57 18 118 21 07 74.7 1,040 3 19

CCR-668 164 48 11 40 118 11 31 66.8 1,067 5 33

CCR-692 38 48 30 26 118 10 51 45.7 1,136 2 19

CCR-705 49 48 38 14 118 05 09 19.5 1,222 2 19

Core along Impounded Spokane River

CSA-8 90 45 56 02 118 12 03 34.4 1,172 3 28

Riverine Sediment with Slag

RSS-685 – 48 24 39 118 12 14 165 – – –

RSS-724 – 48 49 12 118 56 08 0 – – –

RSS-743 – 48 58 15 117 38 50 0 – – –

Table 2. Location and depth of six sediment cores and samples of riverine sediment with slag from Lake Roosevelt, Washington, September 10–13, 

2002.

[Core and riverine sediment sample designation indicates nearest Columbia River mile as shown on 7.5-minute USGS quadrangle maps. Locations of 

sediment cores and riverine sediment samples are shown in figure 1. Latitude and longitude are given in degrees, minutes, and seconds. Abbreviations: cm, 

centimeter; m, meter; ft, foot]

8 Vertical Distribution of Trace Elements and Metallurgical Slag in Sediments, Lake Roosevelt, Washington, 2002
ice and shipped to the laboratory to be freeze-dried prior to 

submission for chemical analysis. Elemental concentrations 

were determined on concentrated-acid digests using a mixture 

of hydrochloric-nitric-perchloric-hydrofluoric acids and 

analyzed by inductively-coupled plasma/mass spectrometry 

(ICP/MS) or, in the case of mercury, cold-vapor atomicabsorption spectrometry. Total organic carbon in the cores 

was determined as the difference between total carbon and 

carbonate carbon. These laboratory analyses were conducted 

at the USGS laboratory in Denver, Colorado, using the 

procedures described by Arbogast (1996). 

Quality-assurance and control procedures were 

incorporated into the study to assure that the resulting 

data were of a known and acceptable quality. Potential for 

contamination was minimized by using clean field procedures 

including dedicated core liners for each core. Equipment 

used for subsampling the cores into individual sections 

was thoroughly cleaned between each section using a nonphosphate soap and water. After washing, the equipment was 

thoroughly rinsed first with tap water followed by additional 

rinsing with deionized water. A variety of quality-control 

samples, generated in the laboratory and the field, were 

used including blanks, and replicate and standard reference 

materials. For each core submitted to the laboratory as a 

series of individual sections, an environmental replicate and 

the standard reference sample also were submitted as blindquality assurance samples. The standard reference materials 

used as blind QA samples submitted from the field included 

the National Institute of Standards and Technology’s Buffalo 

River Sediment number 2704 and National Research Council 

of Canada’s PACS-2. The alert criteria for the analysis of 

the standard reference material was 80 to 120 percent of the 

certified concentration.

Pore-water and sediment samples were collected from 

the three upstream sites (CCR-668, CCR-692, and CCR-705) 

using a 14-cm box core. The box core was subsampled at 

three horizons; the surface to 1 cm depth, and the intervals 

from 1 to 2 cm, and 9 to 11 cm. Core subsampling was 

done immediately after the sampler was returned to the boat 

deck minimizing exposure to the atmosphere. The sectioned 

samples were placed in polyethylene bags, which were 

flushed and purged with pure nitrogen gases to remove oxygen 

before sealing then placed in a second polyethylene bag that 

also was purged with nitrogen before sealing. Exposure 

time to the atmosphere typically was less than 5 minutes. 

Samples were returned to mobile laboratory and transferred 

to 100 mL polyethylene centrifuge tubes. The headspace in 

the centrifuge tubes was purged with nitrogen and sealed with 

polyethylene film and spun in a centrifuge for 30 minutes. 

The pore water was decanted from the centrifuge tube, filtered 

using 0.45 micron filter, and acidified with ultra-pure nitric 

acid. The sediment was frozen with dry ice and a portion was 

sent to the laboratory for analysis along with the pore-water 

samples. Pore-water samples were analyzed for trace-element 

concentrations by ICP/MS. Corresponding sediment samples 

were analyzed for trace elements as described above for the 

determination of trace-element profiles. Splits of four of the 

sediment samples, two each from CCR-668 and CCR-705, 

were treated for 30 minutes at 50oC with 0.25 M solution of 

hydroxylamine hydrochloride to remove trace elements sorbed 

to the sediment surface and in iron and manganese hydroxide 

coatings on sediment surfaces (Chao and Zhou, 1983). The 

residual sediment after leaching was then analyzed for trace 

elements in the same manner as the untreated sediment 

samples. 

Cs-137 concentrations were measured by gamma 

counting and reported as picoCuries per gram (pCi/g). In the 

laboratory, sediment samples for elemental analysis were 

weighed, frozen, freeze-dried, weighed again, and then ground 

to a fine powder. Wet and dry weights were determined and 

used along with an assumed density of solids of 2.5 g/cm3, 

to estimate porosity and bulk density used to calculate mass 

accumulation rates in the cores. As a check on assumed 

densities, measured densities were determined for 20 percent 

of samples from volumes of homogenized wet sediment, 

which were weighed, dried, and then weighed again so that 

bulk density and the density of solids could be calculated. 

Measured densities were about 2.2 to 2.5 g/cm3 and were not 

sufficiently different from the assumed density to warrant 

individual analysis.

Isolation and Identification of Slag Particles

Samples from selected intervals of the cores used to 

determine trace-element profiles were examined for slaglike particles. Intervals were selected based on elevated 

concentrations of trace elements identified in the analysis of 

slag samples, which included zinc, copper, antimony, and 

silver. Chemical and physical characteristics of relatively 

unweathered slag particles were determined from slag 

particles isolated in sample RSS-743 collected from a sand bar 

in the Columbia River (RM 743), about 1.5 km downstream 

of the International Boundary. Slag particles were more 

weathered in samples from RSS-724 and RSS-685 sites. 

Slag was characterized using a petrographic microscope and 

a Noran 660 SSI scanning-electron microscope equipped 

with an energy-dispersive X-ray spectrometer (SEM/EDS). 

Heavy mineral fragments and slag particles were separated 

from selected core sediments in which slag particles were not 

readily observable with a binocular microscope. The sediments 

were suspended in sodium-polytungstate solution (density 

of 2.9 g/cm3) and then the heavy fraction was separated by 

centrifugation (Commeau and others, 1992). Slag particles 

from the heavy fractions were selected for examination by 

petrographic microscope and semi-micro elemental analysis 

using the SEM/EDS. 

Data Collection and Analysis 9
Accumulated Sediments in 

Lake Roosevelt

Description of Cores and Accumulated 

Sediments 

Sediment cores ranging in length from 38 to 164 cm were 

collected from six sites in Lake Roosevelt (fig. 1 and table 2). 

The sediments recovered in the cores generally were grayish 

to dark olive gray in color throughout the core length. Near the 

surface (0 to 2 cm depth), sediments were often reddish-brown 

with a 0.2-0.4 cm layer of black material, and mottling was 

common in the upper 20 cm of cores. Gas vesicles from 0.1 

to 0.3 cm were common as was a sulfurous odor. A sand-size 

particle of slag was noted in the soil-sediment interface of core 

CCR-705. Organic material such as root-hairs was observed in 

some intervals. 

The pre-reservoir sediments that were encountered 

were easily distinguished by differences in sediment color 

and texture. Pre-reservoir sediments were encountered in 

only one of the six cores analyzed, site CCR-705, which 

also was the only site located away from the pre-reservoir 

channel. The base of CCR-705 below 39 cm contained black 

sediments with organic fragments, such as root hairs. While 

subsampling CCR-705, a large slag-like particle was observed 

near the interface of the soil and lacustrine sediments. Prereservoir sediments also were encountered at a site near 

RM 685. The gravity cores recovered at this site contained 

insufficient (less than 20 cm) lacustrine sediments needed for 

developing a detailed trace-element profile. About 50 cm of 

sandy material containing a significant fraction of slag-like 

particles was beneath the lacustrine sediments. The sandy 

material was interpreted to be a fluvial deposit of the prereservoir Columbia River. Although the interval of lacustrine 

sediments was insufficient to meet sampling requirements for 

subsectioning, a sample of the sandy material was retained 

for analysis of slag (RSS-685). During sampling, the coring 

equipment encountered hardrock material substantially 

denting the hardened stainless steel nose-piece of the core 

barrel at mid reservoir sites CCR-643 and CCR-692 and at 

the Spokane Arm site CSA-8. The hardrock material was 

believed to be the pre-reservoir bedrock surface indicating that 

in the locations sampled, the total thickness of accumulated 

sediments within the reservoir was less than the 3 m length of 

the coring equipment. Lake sediments greater than the 

3 m length of the coring equipment were not observed while 

collecting cores from Lake Roosevelt.

Cesium-137 Concentrations and Rates of 

Sediment Accumulation

Assignment of Time Stratigraphic Horizons

Time horizons were assigned to each core based on 

the stratigraphic position of significant changes in the 

concentration profile of Cs-137. Additional time-stratigraphic 

markers used in assignment of time horizons within the 

sediment core included (1) the upper sediment surface, 

assigned the date of sample collection and (2) the lower 

surface of the accumulated lake bed sediments assigned a time 

coincident with the initial filling of the reservoir. 

Cs-137 is a radioactive isotope of cesium whose 

presence in the hydrologic environment is directly related to 

above-ground testing of thermonuclear weapons conducted 

in the 1950s and early 1960s. Because Cs-137 is rapidly 

removed from the atmosphere by precipitation and fallout 

and has a strong affinity for fine-grained sediment particles 

that accumulate in lake bed sediments, the concentrations 

profile of Cs-137 in lake sediments can be used to identify 

sediments deposited at the beginning and end of the period of 

atmospheric testing of thermonuclear weapons. The period of 

major atmospheric testing of thermonuclear weapons began 

in November 1952 followed by increasing numbers of tests 

in the following years (U.S. Department of Energy, 2000). 

Substantial concentrations of Cs-137 greater than background 

concentrations were widely detected in lacustrine sediments 

beginning in 1954. Undisturbed sediments deposited prior to 

1954 do not contain significant measurable concentrations 

of Cs-137. Atmospheric testing of thermonuclear weapons 

increased over the years until autumn 1963 when the Limited 

Test Ban Treaty was signed and atmospheric testing of 

thermonuclear weapons was halted by most Nations that were 

testing thermonuclear weapons at that time. A substantial peak 

in Cs-137 concentrations occurs in sediment deposited during 

1963-64 as the result of nearly 100 atmospheric tests that were 

conducted in the year prior to signing the Limited Test Ban 

Treaty (U.S. Department of Energy, 2000). 

The resulting characteristic or ideal profile of Cs-137 

in lake sediments is that of relatively small concentrations in 

sediment at the sediment-water interface with concentrations 

gradually increasing with depth to a maximum value (which 

varies based on geographic location); below this point, the 

concentration of Cs-137 gradually decreases to a point where 

its concentrations are either undetectable or decrease sharply 

to concentrations much less than 0.1 pCi/g or background 

concentrations (Charles and Hites, 1987). Two points in this 

10 Vertical Distribution of Trace Elements and Metallurgical Slag in Sediments, Lake Roosevelt, Washington, 2002
profile are useful in assigning time stratigraphic horizons. The 

location of maximum concentration is indicative of the period 

of maximum deposition around 1964. The point in the profile 

below the maximum concentration at which Cs-137 ceases 

to be detectable or where concentrations decrease well below 

0.1 pCi/g is attributed to the beginning of Cs-137 deposition 

in 1954. Non-ideal Cs-137 profiles that result from physical 

or biological mixing of sediments as well as variations in 

sediment source material and wave-induced remobilization of 

fine-grained sediments from the shallow zones to deeper zones 

may still provide useful stratigraphic markers for the dates 

of the onset and peak Cs-137 deposition (Charles and Hites, 

1987). Cs-137 profiles in bed sediments have been widely 

used to determine sediment-accumulation rates (Ritchie and 

McHenry, 1990; Crusius and Anderson, 1995; and Van Metre 

and others, 1997).

The concentration of Cs-137 measured in core sediments 

from Lake Roosevelt ranged from <0.01 to 1.8 pCi/g. The 

concentration profiles of Cs-137 within cores CCR-643, 

CCR-668, and CCR-692 (fig. 3) were non-ideal but showed 

the basic characteristics of ideal Cs-137 profiles in lake 

sediments. Peak Cs-137 concentrations associated with the 

suspension of atmospheric weapons testing in 1964 could be 

identified in all six cores, but often contained short intervals 

in which the concentration of Cs-137 decreased substantially 

followed by a return to equal or larger concentrations. 

The pronounced decreases in Cs-137 concentrations were 

attributed to the influx of sediments from landslides. This 

effect was most readily observed in the Cs-137 profile of 

CCR-705, but also was present in the other cores. 

Concentrations of Cs-137 in the lowest sections of the 

core CCR-705 range from <0.01 to 0.02 pCi/g; this interval 

(40-46 cm) included pre-reservoir soils and can be used to 

identify the range of background Cs-137 concentrations 

in the Lake Roosevelt area. In the overlying sections 

(34-38 cm), the concentrations of Cs-137 were 0.16 and 

0.18 pCi/g, indicative of the influx of Cs-137 from 

atmospheric weapons testing. However, the concentrations 

of Cs-137 in the next three overlying intervals (22-32) 

decreased by 80 to 95 percent to concentrations of <0.01 to 

0.04 pCi/g, which were immediately overlain by a section 

(18-20 cm) containing the maximum measured Cs-137 

concentration in that core of 1.2 pCi/g. The intervals in which 

the concentrations of Cs-137 decrease markedly are indicative 

of disruption of the normal sedimentation processes and 

are believed to be the result of the episodic influx of bank 

sediments. Landslide sediments would be devoid of Cs-137 

produced from atmospheric testing of thermonuclear weapons 

and thus dilute the concentration of Cs-137 in the more steady 

influx of fluvial sediments to the reservoir from upstream 

drainage basins. The influx of the bank sediments likely is due 

to the many landslides that have occurred along the margins of 

the reservoir (Jones and others, 1961). 

The characteristic features of typical Cs-137 profiles 

in sediments from Lake Roosevelt were present in sufficient 

detail to assign time horizons to intervals associated with the 

end of atmospheric testing of thermonuclear weapons, and the 

beginning of the testing period also was observable in some 

cores. Maximum Cs-137 concentrations attributable to the 

1964 depositional period were identifiable in all cores (see 

fig. 3); however, the influx of landslide sediments substantially 

affected the Cs-137 profiles in core CCR-668 and interpolation 

between intervals containing Cs-137 concentrations of 

0.76 and 0.78 were used to estimate the depth of sediments 

deposited around 1964 (see fig. 3 and table 3). The 1954 

time horizon was assigned to the first appearance of Cs-137 

greater than 0.04 pCi/g (two times the highest concentration 

in pre-reservoir soil sediments) and was identified in two 

cores (CCR-668 and CCR-705). Additional time horizons 

used in the evaluation of the patterns of historical deposition 

of sediment and trace elements in Lake Roosevelt include 

the sediment surface at the time of sampling (2002) and the 

contact between lacustrine and pre-reservoir sediments (1941).

The sediment recovered in all six cores included at least 

60 percent of the reservoir sedimentary record, as peak Cs-137 

concentrations exceeding 0.7 pCi/g were present in all cores. 

The sedimentary record in three cores (CCR-624, CCR-668, 

and CCR-705) extended through the 1954 time horizon to 

include 80 percent or more of the sediment record. Core 

CCR-705 was the only core where the sedimentary record 

included the contact between lacustrine and pre-reservoir 

sediments (soil), thereby extending from the time of sampling 

to the time of initial filling of the reservoir. Although core 

CCR-624 did not encounter pre-reservoir sediments, the 

sediment accumulation data indicates that the sediments in the 

lowest sections of that core were deposited in the early 1940s, 

thereby providing a nearly complete sedimentary record of 

Lake Roosevelt. The sedimentary record for core CCR-668 

extended to the early 1950s, although the earliest sediments 

recovered in cores CCR-643, CCR-692, and CSA-8 were 

deposited at times between 1953 and 1964.

Accumulated Sediments in Lake Roosevelt 11
Figure 3. Vertical distribution of cesium-137 concentrations in sediment cores from Lake Roosevelt, Washington, 

September 2002.

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12 Vertical Distribution of Trace Elements and Metallurgical Slag in Sediments, Lake Roosevelt, Washington, 2002
Marker interval

Core identification No.

CCR-624 CCR-643 CCR-668 CCR-692 CCR-705 CSA-8

Depth to date horizons identifed in cores (ft)

Total core length including some sediment lost in retrieving core 48 74 173 38 49 90

Markers identified

 Undisturbed sediment surface 2002 0 0 0 0 0 0

 Depth to Cs-137 peak (1964) 28 50 100 27 19 62

 Depth to first appearance of elevated Cs-137 (1954) 38 – 147 – 37 –

 Depth to pre-reservoir surface (1941) 48est – – – 44 –

Linear estimate of sediment accumulation rate (cm/yr)

Estimate between marker horizon

 1941–2002 0.79 – – – 0.72 –

 1954–2002 .79 – 3.1 – .77 –

 1964–2002 .74 1.3 2.6 0.71 .50 1.7

 1941–1964 .87 – – – 1.1 –

 1954–1964 1.00 – 4.7 – 1.8 –

 1941–1954 .77 – – – .54 –

 Whole core minimum value .79 1.5 2.8 .79 .80 1.9

Mass estimate of sediment accumulation rate [(g/cm2))/yr]

 1941–2002 0.42 – – – 0.53 –

 1954–2002 .44 – 1.6 – .45 –

 1964–2002 .44 0.82 1.2 0.61 .24 0.00

 1941–1964 >.38 – – – 1.1 –

 1954–1964 .44 – 3.1 – 1.9 –

 1941–1954 .33 – – – .38 –

 Whole core minimum value .42 >.76 >1.4 >.63 .53 .00

Table 3. Time horizons and sediment accumulation rates for six cores from Lake Roosevelt, Washington.

[est, estimate; ft, foot; cm/yr, centimeter per year; (g/cm2)/yr, gram per square centimeter per year; >, greater than]

Sedimentation Rates 

The rates of sediment accumulation, measured as both 

the length and mass of accumulated sediments between 

two time horizons within the sediment core are shown in 

table 3. Sedimentation rates based on length of accumulated 

sediments are reported as centimeters per year (cm/yr) and 

are subject to sampling artifacts, particularly core shortening, 

moisture content, and natural compaction of buried sediments. 

Compaction of the core within the coring tool barrel caused 

by friction along the core wall during sampling may reduce 

the total length of the core as much as 30 to 40 percent (Peter 

VanMetre, U.S. Geological Survey, unpublished data, 2002). 

Mass accumulation rates are reported as grams per square 

centimeter per year [(g/cm2)/yr]. Mass accumulation rates are 

based on the dry mass of sediments per unit area between time 

horizons and are not prone to the effects of core shortening 

and compaction. 

Linear estimates of sediment accumulation rate in the 

sediment cores, based on the observed date horizons, ranged 

from 0.50 to 4.7 cm/yr, and typically were between 0.77 to 

1.8 cm/yr (table 3). Mass estimates of sediment accumulation 

rates ranged from 0.24 to 3.1 (g/cm2)/yr and typically were 

between 0.42 and 1.00 (g/cm2)/yr. Within individual cores, 

the rate of sediment accumulation varied and typically was 

largest in the lower core sections for sediment deposited 

prior to 1964. Current rates (2003) of sediment accumulation 

likely are substantially smaller because the completion of 

additional dams upstream of Lake Roosevelt on the Columbia 

[Hugh Keenleyside Dam (1968)], Kootenay [Brilliant Dam 

(1940s)], and Pend Oreille Rivers [(Waneta Dam (1950s)] 

have further reduced the sediment input to the reservoir and 

the stabilization of the reservoir shoreline has reduced the 

frequency and magnitude of landslides. 

Accumulated Sediments in Lake Roosevelt 13
Table 4. Summary of concentrations of arsenic, cadmium, copper, lead, mercury, and zinc in all sample core subsections from Lake Roosevelt, 

Washington.

[Average concentrations in crustal rocks: Data from Rose and others, 1979. Range of reference: Data from Bortleson and others, 1994, and Majewski and 

others, 2002. Clean-up guideline: Guidelines from CCT. Clean-up guidelines adopted by Confederated Tribes of the Colville Reservation (2003)]

Constituent Number of 

samples

Concentrations, in milligrams per kilogram (mg/kg)

Average Minimum Maximum Median 10th percentile 90th percentile

Arsenic 84 14 2.1 34 13 7.1 20

Cadmium 84 8.6 1.4 23 7.5 2.4 16

Copper 84 68 18 250 53 32 130

Lead 84 310 61 920 260 83 610

Mercury 82 .82 .08 2.8 .58 .1 1.9

Zinc 84 930 151 2,200 970 330 1,500

Constituent

Average 

concentration in crustal 

rocks (mg/kg)

Range of

reference 

concentration 

(mg/kg)

Percentage

of samples

exceeding 

upper 

reference

Percentage 

of samples

exceeding

3X upper 

reference

Percentage 

of samples

exceeding

10X upper 

reference

Clean-up

guideline 

(mg/kg)

Percentage 

of samples

exceeding

clean-up 

guideline

Arsenic 2 3.2–10 78 1 0 9.8 78

Cadmium .1 <0.1–0.4 100 100 77 .99 100

Copper 50 9–25 99 26 0 31.6 90

Lead 10 14–47 100 66 20 35.8 100

Mercury .02 0.01–0.07 100 70 47 .18 74

Zinc 80 50–150 100 80 8 121 100

Concentrations of Trace Elements in 

Accumulated Sediments

Concentrations of arsenic, cadmium, copper, lead, 

mercury, and zinc were high throughout the six sediment 

cores collected from Lake Roosevelt. Maximum 

concentrations in the core samples were as high as 

2,200 mg/kg for zinc, 920 mg/kg for lead, and 250 mg/kg 

for copper, with median concentrations of 970, 260, and 

53 mg/kg, respectively (table 4). Concentrations of arsenic, 

cadmium, and mercury were lower; with maximum 

concentrations as high as 34 mg/kg for arsenic, 23 mg/kg 

for cadmium, and 2.8 mg/kg for mercury, with median 

concentrations of 13, 7.5, and 0.58 mg/kg, respectively. 

Concentration data for 54 elements determined for bulksediment samples from the six cores are shown in table 5

(at back of report). The analytical results of the associated 

quality-control samples, presented in table 6 (at back of 

report), indicate acceptable levels of bias and variability in the 

sample analytical data. 

Bias and variability of the laboratory data were within 

acceptable limits. Quality-assurance samples were submitted 

as double blind samples; the laboratory was not informed 

which samples were quality-assurance samples nor the specific 

standard reference material that was used. Bias in the samples 

were assessed as a percentage of recovery by comparison of 

the reported concentrations of the standard reference material 

to the concentrations determined by the laboratory. Variability 

was assessed by comparison of the relative percentage of 

difference of replicate environmental samples. Data for the 

quality-control samples submitted from the field are shown 

in table 6. The median recovery for all trace elements for 

which certified or reference concentrations were reported 

was 99 percent; however, 5 percent of the laboratory analyses 

were outside the target recovery range of 80-120 percent. 

The median recoveries for six analyses of standard reference 

materials for arsenic, cadmium, copper, lead, mercury, and 

zinc were 94, 96, 105, 96, 100, and 96 percent, respectively. 

Variability generally was small, the median difference of the 

replicated environmental samples was 2.4 percent with 3.8 

percent of the replicated analyses outside the target range of 

less than 20 percent difference between the replicate samples. 

Of the six trace elements of concern, the analysis of lead 

showed variability ranging from 87 to 124 percent while 

variability in copper concentration of one of the environmental 

replicate pairs was different by 46 percent. Review of the 

laboratory process sheets confirmed the variability in the 

copper analysis. The deviations observed in the copper and 

lead data for these samples were not observed among the other 

quality-assurance samples and thus considered outliers that did 

not significantly affect the overall acceptability of the data. 

14 Vertical Distribution of Trace Elements and Metallurgical Slag in Sediments, Lake Roosevelt, Washington, 2002
Concentrations of trace elements in core sediments 

were compared to reported concentration of trace elements in 

reference sediments that were collected from bank material 

adjacent to the reservoir (Majewski and others, 2003) and 

river sediment collected upstream of the smelter (Bortleson 

and others, 1994). The largest concentrations in these 

reference sediments were reported as 10 mg/kg for arsenic, 

0.4 mg/kg for cadmium, 25 mg/kg for copper, 47 mg/kg for 

lead, 0.07 mg/kg for mercury, and 150 mg/kg for zinc. These 

reference values are intermediate between estimates of natural 

background concentration, determined as the 95th percentile

level, for concentrations determined in the less than 63 micron 

fraction and less than 4 mm fraction of stream sediments 

from the area surrounding Trail, British Columbia (Reyes and 

others, 2004). 

Compared to the concentration of trace elements from 

reference sites, concentrations of cadmium, copper, lead, 

mercury, and zinc were elevated in nearly 100 percent of 

core samples analyzed, and concentrations of arsenic were 

elevated in 78 percent of the samples analyzed (table 4). 

Concentrations of cadmium and mercury exceeded the 

upper range of background reference concentrations by 10 

times or more in 77 and 47 percent of the samples analyzed, 

respectively. Concentrations of lead and zinc exceeded 

reference concentrations by 10 times in less than 25 percent 

of the samples analyzed. The concentrations of arsenic and 

copper were least often elevated above concentrations in 

reference sediments. In most cores, maximum concentrations 

of arsenic and copper generally were least elevated, typically 

less than 3 to 4 times the upper range of concentrations in 

reference sediments. However, at site CCR-692, copper 

concentrations were substantially larger than in the other 

cores, with the concentration in many intervals exceeding 

reference concentrations by 5 to 10 times.

All samples exceeded cleanup guidelines adopted 

by the Confederated Tribes of the Colville Reservation

(CCT) (Colville Confederated Tribes, 2003) for cadmium, 

lead, and zinc and more than 70 percent of samples 

exceeded cleanup guidelines for mercury, arsenic, and 

copper (table 4). The sediment-quality guidelines adopted by 

the CCT were developed from the consensus based threshold 

effects concentrations for freshwater ecosystems 

(MacDonald and others, 2000). 

Trace-Element Profiles

The vertical distribution of trace elements was determined 

by generating a concentration-depth profile for each core for 

the six trace elements of concern. Similarities and differences 

can be observed in the concentration-depth profiles of arsenic, 

cadmium, copper, lead, mercury, and zinc of cores from 

different locations in Lake Roosevelt (figs. 4A-4F). These 

profiles show the extent that trace-element concentrations 

in the accumulated sediments of Lake Roosevelt exceed 

background reference concentrations and the concentration 

levels adopted as Trace-Element Clean-up Guidelines by the 

Confederated Tribes of the Colville Reservation (Colville 

Confederated Tribes, 2003). The concentration profiles 

from the sediment cores support conclusions of previous 

investigators of the widespread occurrence of trace elements 

in bed sediments of Lake Roosevelt and generally decreasing 

concentrations in sediments toward the downstream reaches of 

the reservoir.

Zinc concentrations were largest and covered the 

widest range of the six trace elements of concern (table 5 and 

fig. 4A). As found in previous studies, surficial concentrations 

of zinc were smaller at downstream locations in the reservoir. 

Concentrations of zinc exceeded the range of concentrations 

in reference sediments and clean-up guidelines throughout 

the entire core at all six sites. Eighty percent of all samples 

exceeded the upper range of reference concentrations by a 

factor of three. Maximum measured concentrations typically 

were located in the lower or middle one-third of the cores. 

In all cores along the pre-reservoir channel of the Columbia 

River, a trend of decreasing zinc concentrations was observed 

between sediments deposited near the 1964 time horizon 

and those in recently deposited sediments. Most decreases 

were about 50 to 70 percent. The largest decrease was in core 

CCR-668 where concentrations decreased from 1,500 mg/kg 

at mid-core to about 300 mg/kg at the surface. Decreasing 

zinc concentrations near the surface were not as apparent 

in the core from the Spokane Arm (CSA-8) where zinc 

concentrations appear to fluctuate about a central value of 

1,300 mg/kg throughout the entire core and do not show a 

clear trend of decreasing concentrations. The influx of bank 

material from landslides likely explains the intervals of lower 

concentrations in the middle of cores CCR-624, CCR-643, and 

CCR-705. 

The concentration of lead exceeded the range of 

concentrations in reference sediments and cleanup guideline 

throughout the entire core profile at all six core sites (fig. 4B). 

The concentrations of lead in the cores varied considerably, 

particularly in cores from the lower and mid reaches of 

the reservoir but were much less variable in the core from 

the Spokane Arm. Among all cores, lead concentrations 

ranged from those approaching concentrations in reference 

sediments to concentrations greater than 1,500 mg/kg, 

more than 30 times larger than the upper range of reference 

concentrations. Concentrations were larger in cores from the 

upstream locations, however, the concentrations of lead at 

downstream sites decreased in the more recent sediment near 

the surface, such that lead concentrations in the uppermost 

intervals of these cores approached to within several fold the 

range of clean-up guidelines and reference sediments. The 

largest concentrations of lead in cores along the pre-reservoir 

Columbia River channel were in sediments near the 1964 

horizon or deeper. Lead concentrations in cores from the lower 

and mid reaches of the reservoir typically decreased toward 

the surface by roughly 60 to 80 percent. Lead concentrations 

in the core from the Spokane Arm generally were lower than 

most samples from the lower and mid reaches of the reservoir 

and showed little variation or trend.

Accumulated Sediments in Lake Roosevelt 15
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Figure 4. Vertical distribution of trace-element concentrations in selected sediment cores from Lake Roosevelt, Washington, 

September 2002. 

16 Vertical Distribution of Trace Elements and Metallurgical Slag in Sediments, Lake Roosevelt, Washington, 2002
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18 Vertical Distribution of Trace Elements and Metallurgical Slag in Sediments, Lake Roosevelt, Washington, 2002
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20 Vertical Distribution of Trace Elements and Metallurgical Slag in Sediments, Lake Roosevelt, Washington, 2002
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The profiles of copper concentrations were unique among 

the six trace elements of concern in that an overall trend of 

increasing rather than decreasing concentrations from depth to 

the surface was observed in most of the core profiles (fig. 4C). 

Copper concentrations generally were larger than the range of 

reference concentrations and clean-up guidelines. Only core 

CCR-692 shows a definite trend of decreasing concentrations 

toward the surface, however, concentrations at this site 

were 2 to 5 times larger than at all other core sites. Copper 

concentrations in the Spokane Arm typically are lowest among 

the core profiles; however, the concentration of copper is 

increasing slightly in the more recently deposited sediments 

near the surface.

The longitudinal distribution of arsenic in bed sediments 

of Lake Roosevelt differed from other trace elements in 

that larger arsenic concentrations were more common at 

downstream locations, particularly in core CCR-643 

(fig. 4D). This distributional pattern of comparatively larger 

concentrations in surficial sediments at downstream locations 

in Lake Roosevelt is reverse of the distributional patterns 

reported by Bortleson and others (1994) and Majewski 

and others (2003), although the longitudinal concentration 

gradients in all three studies were small. For cores collected 

along the pre-reservoir Columbia River channel, arsenic 

concentrations were largest near the 1964 horizon (fig. 4D) 

and generally decrease by roughly 40 to 50 percent toward 

the surficial horizon, although the decrease in core CCR-643 

was only about 20 percent. Arsenic concentrations in the 

core collected from the Spokane Arm of the reservoir (CSA8) show a trend of increasing concentrations in the more 

recent sediment horizons. Of the trace elements of concern, 

the concentration of arsenic in sediment of Lake Roosevelt 

are the most similar to concentrations in reference sediment. 

Although arsenic concentrations generally were larger than 

the range of reference concentrations and clean-up guidelines 

at all sites, decreasing concentrations in the upper horizons 

of cores collected along the upper pre-reservoir Columbia 

River channel (CCR-668, CCR-692, and CCR-705) were 

less than CCT cleanup guidelines and within the range of 

concentrations in reference sediments. Concentration profiles 

from the lower reaches of the reservoir (CCR-624 and CCR643) were decreasing, nevertheless, the concentrations in the 

surficial sediments remained slightly elevated relative to the 

reference concentrations and CCT clean-up guidelines. 

Cadmium was the only trace element for which 

concentrations in all samples throughout each core exceeded 

the upper range of reference sediments by a factor of three or 

more and for which all samples exceeded the CCT clean-up 

guideline (fig. 4E). Sediments in the core from the Spokane 

Arm of the reservoir generally contained larger cadmium 

concentrations than sediments from the rest of the reservoir. 

Cadmium concentrations decreased from the 1964 horizon 

toward the surface in all cores. Cadmium concentrations 

in recently deposited sediments from the top of the cores 

typically were about 20 to 50 percent less than those in 

sediments deposited near the 1964 horizon.

Concentrations of mercury were consistently larger than 

the range of background reference concentrations and cleanup guidelines at all sites along the pre-reservoir Columbia 

River channel (fig. 4F). Mercury concentrations in all core 

samples from the Spokane Arm exceeded the upper range of 

concentrations in reference sediments, however, concentrations 

in only two of these samples exceeded CCT clean-up 

guidelines. In the cores from along the pre-reservoir Columbia 

River, large mercury concentrations have been widespread but 

generally have decreased in sediments above the 1964 horizon, 

particularly in the most recent sediment intervals. The profile 

in core CCR-692 shows an increase in mercury concentration 

in the two most recent sections of the profile, which may be 

associated with the concurrent large increase in total organic 

carbon in those intervals (see table 5). 

Overall, the depth concentration profiles typically show 

that concentrations of arsenic, cadmium, lead, mercury, and 

zinc often were highest in the lower to mid sections (closer 

to the bottom) and the concentrations of copper often were 

highest (closer to the surface) in the trace-element profiles. In 

several individual cores (CCR-624, CCR-643, CCR-668, and 

CCR-705), well-defined trends of decreasing concentrations 

of arsenic, lead, zinc, and to a lesser degree cadmium, were 

observed in the upper sections of cores corresponding to 

sedimentation that occurred since the 1964 horizon. The 

concentration profiles for arsenic, cadmium, lead, zinc, 

and to a lesser extent mercury also clearly show decreasing 

concentrations in more recently deposited sediments 

throughout the reservoir as reported by Majewski and others 

(2003). However, the concentration profiles for copper 

generally show trends of increasing concentrations in more 

recent sediments particularly in CCR-705. 

Trace-element profiles for the core collected from the 

Spokane Arm of the reservoir showed several pronounced 

differences compared to the trace-element profiles in cores 

collected from along the mainstem of the Columbia River. 

The most notable differences were the comparatively larger 

concentrations of zinc and cadmium, and lower concentrations 

of mercury, lead, and copper. There also was an increasing 

trend toward the surface in the concentration of arsenic in 

the upper one-half of the profile and a decreasing trend of 

cadmium in the upper one-third of the profile; concentrations 

of copper, lead, mercury, and zinc remained relatively constant 

throughout the core profile. These results differ from those 

of Grosbois and others (2001), who reported decreasing 

concentrations of all six of these trace elements in the upper 

sections of two sediment cores obtained from the Spokane 

Arm of the reservoir, as well as for cores from other areas 

of the Spokane River basin. They attributed the trend of 

decreasing concentrations in the upper sections of cores to 

the installation of jig-tailing settling ponds at mine sites and a 

general improvement in environmental stewardship occurring 

within the Spokane River basin over the last 20 to 30 years. 

22 Vertical Distribution of Trace Elements and Metallurgical Slag in Sediments, Lake Roosevelt, Washington, 2002
River channel. Trace-element concentrations in the core 

collected downstream of the confluence of the Spokane 

River (CCR-624) shows predominantly the influences of 

trace-element input from the Columbia River with limited 

influence from input from the Spokane River basin. The 

fact that cadmium concentrations at times exceeded arsenic 

concentrations in deeper sediments from the 1950s time 

horizons may be an example of input from the Spokane River 

basin on trace-element concentrations in bed sediments of the 

lower reach of Lake Roosevelt. 

The differences in the relative concentrations of trace 

elements in the cores collected in the Spokane Arm of the 

reservoir compared to cores collected along the Columbia 

River were most likely related to differences in the source 

areas contributing sediments to the Spokane and Columbia 

Rivers. Reservoir sediments from along the mainstem of the 

Columbia River primarily were affected by inputs from the 

Columbia River whereas sediments in the Spokane Arm of the 

reservoir were primarily affected by sediment sources from the 

Spokane River, which includes the Coeur d’Alene mining area 

(Horowitz and others, 1993). 

The differences in the trace-element concentrations in 

core sediments from along the pre-reservoir channel of the 

Columbia River compared to sediments from the Spokane 

Arm are more clearly observed by the comparison of ratios 

of the concentration of zinc to lead versus ratios of the 

concentration of cadmium to mercury (fig. 5). Data for 

sediments from all cores obtained along the Columbia River 

plot in a single close grouping whereas ratios of zinc to lead 

and cadmium to mercury were substantially larger for data 

from the Spokane Arm and are more scattered and plot away 

from the area where data from the Columbia River plot. The 

ratios of zinc to lead and cadmium to mercury typically were 

about 2 to 4 and 3 to 20, respectively, in the sediments from 

the cores collected from the reservoir locations along the 

mainstem of the Columbia River. These same ratios in the 

sediments from the Spokane Arm of the reservoir were much 

larger, typically about 10 to 14 and 70 to 100, respectively. 

Other comparisons such as plots of the relation of calciumcarbonate concentrations or aluminum-titanium concentrations 

also show substantially different patterns for sediments from 

the Spokane Arm compared to sediments from the Columbia 

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Figure 5. Ratios of cadmium to mercury and zinc to lead in samples from sediment cores from 

Lake Roosevelt, Washington, September 2002.

Accumulated Sediments in Lake Roosevelt 23
Patterns of Trace-Element Profiles Within 

Individual Cores

Concentration profiles of arsenic, cadmium, copper, 

lead, mercury, and zinc showed similar patterns of variation 

within all cores. The relative concentrations of trace elements 

remained nearly constant throughout the trace-element 

profiles. Zinc was present in the largest concentration followed 

systematically by the concentrations of lead, copper, arsenic, 

cadmium, and mercury, although there are a several instances 

in the cores from the Spokane Arm and CCR-624 where the 

concentrations of cadmium exceeded arsenic concentrations. 

Within the core sediments, the general pattern of relative 

concentrations remains constant; even as concentrations were 

decreasing in the more recent sediments in the upper one-half 

of the cores. The pattern of relative concentrations observed 

in the core profiles generally follows relative average crustal 

abundances of trace elements reported by Rose and others 

(1979) (see table 4) with the exception that in lacustrine 

sediments of Lake Roosevelt, the concentration of lead 

generally exceeds copper by 3 to 4 times.

Because within core variations in concentrations of zinc, 

lead, cadmium, and mercury were consistent, concentration 

profiles often were near parallel (figs. 6A-6F). The influx 

of bank material and its diluting effect on bed-sediment 

concentrations accentuates variation and the near parallel 

concentration profiles. Variations in concentrations of arsenic 

commonly followed the general trends of the other four 

trace elements but were not nearly as extensive or consistent. 

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Figure 6. Vertical distribution of trace-element concentrations in six sediment cores from Lake Roosevelt, Washington, September 

2002.

24 Vertical Distribution of Trace Elements and Metallurgical Slag in Sediments, Lake Roosevelt, Washington, 2002
The similar pattern of variation in the concentration of zinc, 

lead, cadmium, and mercury observed in cores from along 

the mainstem of the Columbia River channel indicates that 

a single source, such as inflow from the Columbia River, is 

dominating the depositional patterns of these trace elements 

throughout most of the reservoir. The profiles often display 

features that were distinctive to an individual core indicating 

that localized conditions, such as landslides, had a major 

influence on the concentrations of trace elements that were 

being deposited at a particular location. The concentration 

profiles for each core provide an integrated historical record 

that incorporates regional and localized influences of the 

changing depositional concentrations of trace elements at 

specific locations in the reservoir.

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Figure 6.—Continued

Accumulated Sediments in Lake Roosevelt 25
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Figure 6.—Continued

26 Vertical Distribution of Trace Elements and Metallurgical Slag in Sediments, Lake Roosevelt, Washington, 2002
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Figure 6.—Continued

Accumulated Sediments in Lake Roosevelt 27
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Figure 6.—Continued

28 Vertical Distribution of Trace Elements and Metallurgical Slag in Sediments, Lake Roosevelt, Washington, 2002
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Figure 6.—Continued

Accumulated Sediments in Lake Roosevelt 29
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Figure 7. History of slag and trace elements in liquid effluent discharged to Columbia River by Trail smelter, British Columbia, 1940–2000.

(Source of data: Cominco, 1992, 2001; U.S. Environmental Protection Agency, 2003; and William Duncan, Teck-Cominco, written commun., 

2004.)

The profiles from CCR-643 illustrate the effect of 

the episodic influx of sediments from landslides and bank 

erosion. Concentrations of zinc, lead, cadmium, and mercury 

decrease by roughly 50 to 80 percent in the intermediate 

interval between 22 to 42 cm (fig. 6B). The concentrations 

of arsenic and copper also decrease in this interval but to a 

lesser extent. Cs-137 concentrations are about 0.6 pCi/g in the 

sediment intervals near 20 and 42 cm within the profile but 

decrease to about 0.1 pCi/g in intervals between 20 and 42 cm. 

Ancillary trace-element concentrations data (table 5) show the 

concentrations of total cesium, titanium, carbonate, and to a 

lesser extent calcium, increased in the same interval as might 

be expected from the influx of landslide material composed 

of glacial sediments derived from carbonate bedrock. Similar 

patterns of a sharp decrease in trace-element concentrations 

attributed to episodic events also were observed in profiles of 

cores CCR-624, CCR-668, CCR-705, and CSA-8 (figs. 6A, 

6C, 6E, 6F).

The trace-element profiles from cores collected 

along the pre-reservoir Columbia River channel reflect the 

recorded changes in the effluent discharges from the Trail 

smelter during the last 30 years. The relative magnitude of 

trace-element concentrations observed in the core sediments, 

with zinc>lead>copper>arsenic>cadmium>mercury, generally 

matches, with the exception of arsenic, available information 

on trace-element loading rates in liquid effluent discharged 

from the Trail smelter since the mid-1970s (fig. 7). The 

concentration of cadmium is larger than arsenic in the effluent 

discharge, however, the concentration of arsenic typically is 

larger than the concentration of cadmium in core sediments. 

This difference may be due to differences in sorption 

properties of the two elements or additional natural sources of 

arsenic. Similar information on the concentration of copper 

in liquid effluent was not available. Since the mid-1970s, the 

amount of trace-element loading in liquid effluent and slag 

discharged to the Columbia River has been reduced through a 

series of improvements and modernizations. Concentrations 

of trace elements were often highest in sections of the traceelement profiles corresponding to the mid-1960s period. 

Decreasing concentrations of trace elements in the more 

recently deposited sediments of the upper one-half of the 

profiles likely reflect the substantial decreased loading of 

trace elements in the liquid effluent discharged from the Trail 

smelter. These trends also reflect the smelter’s strong influence 

on the trace-element composition of bed sediment throughout 

Lake Roosevelt.

30 Vertical Distribution of Trace Elements and Metallurgical Slag in Sediments, Lake Roosevelt, Washington, 2002
pore-water concentrations of some trace elements at depth. 

This explanation is supported by the lack of sulfate in pore 

water from cores CCR-668 and CCR-692 and the decreasing 

sulfate concentrations in the deeper intervals of core CCR705. Under reducing conditions, which are thought to be 

present in sediments with pore water iron concentrations 

greater than 1,000 mg/L, sulfate reducing bacteria can readily 

convert sulfate to sulfide ions. In the presence of sulfide ions, 

dissolved metals such as iron, lead, mercury, and cadmium 

can form highly insoluble precipitates that are removed from 

solution. 

Variability in pore-water concentrations also may occur 

seasonally due to the changing water levels in the reservoir. 

Water levels in the reservoir are lowered about 20 to 80 ft 

during April to June to provide storage volume for snowmelt 

in the upstream drainage basin. The changing lake level 

will affect the hydraulic head in the ground-water system 

discharging to the reservoir, likely increasing ground-water 

discharge during the drawdown period and possibly inducing 

the movement of surface water into the reservoir bed when 

the reservoir is returned to its normal operating water level. 

The reduction in static pressure during the drawdown period 

possibly increased the hydraulic gradient across the groundwater/surface-water interface increasing the potential for 

movement of pore water out of the bed sediments and into 

the overlying water. Following refilling of the reservoir to 

full pool elevation in June, the movement of water across the 

interface may have been reversed for a time when Columbia 

River water with relatively dilute concentration of trace 

elements may have seeped in the near-surface bed sediments. 

Pore-water samples were collected in mid-July, following 

return of the reservoir to full operating level after the seasonal 

drawdown of pool elevation to 1,265 ft the previous May. 

Information is not available to assess these potential effects on 

the pore-water concentration data. 

A larger fraction of the trace-element concentrations 

in sediments of the mid-reach of Lake Roosevelt occur 

associated with the surface of sediment grains rather than 

associated with the interior matrix of the sediment grains. 

Prior to analysis of trace-element concentrations, four 

sediment samples were treated with hydroxylamine 

hydrochloride reagent to remove trace elements that are 

weakly sorbed to the grain surface or incorporated within 

iron and manganese oxide coatings. Concentrations of trace 

elements in the residual sediment fraction of the samples 

treated with hydroxylamine hydrochloride reagent were 

substantially lower than concentrations in untreated 

sediment samples (table 7). Concentration data for the total, 

residual, and leached fractions of arsenic, cadmium, copper, 

lead, and zinc (table 7) were plotted in figure 9, which 

shows that most of cadmium, copper, lead, and zinc 

concentrations are associated with the leached fraction 

from the surface of the sediment particle or reducible oxide 

coatings that have precipitated onto sediment surfaces. 

Trace Elements in Pore Water and 

Sediment 

The concentrations of trace elements in sediment and 

pore-water matrixes were determined for samples collected 

at several depth intervals (surface to 1 cm, 1 to 2 cm, 

and 9 to 11 cm) in shallow cores collected at sites CCR668, CCR-692, and CCR-705 (table 7, at back of report ). 

Concentrations of mercury were not determined in pore water 

or sediment samples because the pore-water sample volume 

was insufficient for mercury analysis. Some uncertainty is 

associated with the dissolved concentration of trace elements 

in pore water because the concentrations of iron and zinc 

were quite different in replicate samples of pore water 

obtained from the 9 to 11 cm interval from site CCR-668. 

Concentrations of arsenic, cadmium, copper, lead, and zinc 

of the sediment matrix (table 7) also was determined for the 

sediments collected for pore-water analysis. Trace-element 

concentrations determined for pore-water sediments typically 

were within about 15 percent of trace-element concentrations 

reported for the sediments from the same or nearby horizon 

in the cores that were collected to determine concentration 

profiles within the accumulated sediments at each site 

(table 5). 

Concentrations of dissolved arsenic, cadmium, copper, 

lead, and zinc in pore waters collected from these sediments 

(fig. 8) were often larger than ambient dissolved 

concentrations measured in Columbia River water at 

the Northport sampling station between 1992 and 2000 

(Bortleson and others, 1994; Kelly and others, 2001). Thus, 

concentrations of these trace elements dissolved in pore water 

is most likely due to their close association to the elevated 

trace-element concentrations in the adjacent sediments through 

either leaching or remobilization of trace elements from the 

sediment phase to the pore-water phase. If present, slag may 

be a continuous source of zinc, and copper, which are present 

in slag in comparatively large concentrations. Recent studies 

have clearly shown that copper, lead, zinc, and other trace 

elements are readily leached from similar metallurgical slags 

(Parsons and others, 2001; Lottermoser, 2002; Piatak and 

others, 2004), although earlier studies by the Trail smelter 

report that slag was relatively inert with respect to the leaching 

of trace elements based on U.S. Environmental Protection 

Agency’s Toxicity Characteristic Leaching Procedure 

(Cominco, 1991). 

Some trace-element concentrations in pore water 

show a gradient of decreasing concentrations with depth 

that is opposite the trace-element concentration gradient 

in the sediment. Cadmium, copper, and to a lesser extent 

zinc follow this pattern. No clear pattern was noted for the 

pore-water concentration gradients of arsenic and lead. 

The precipitation of metal sulfides may explain the smaller 

Trace Elements in Pore Water and Sediment 31
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Figure 8. Vertical distribution of concentrations of dissolved arsenic, cadmium, copper, lead, and zinc in pore waters from 

sediment core sampling sites CCR-668, CCR-692, and CCR-705, Lake Roosevelt, Washington.

32 Vertical Distribution of Trace Elements and Metallurgical Slag in Sediments, Lake Roosevelt, Washington, 2002
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Figure 9. Concentrations of arsenic, cadmium, copper, lead, and zinc in whole sediment and leached residual (following extraction with 

hydroxylamine hydrochloride) from sediment core sampling sites CCR-668 and CCR-705, Lake Roosevelt, Washington, July 2003.

Trace Elements in Pore Water and Sediment 33
Thus, most of these trace elements are associated with the 

surface of the sediment particle where they are relatively 

accessible and are potentially bioavailable or susceptible to 

remobilization. Cadmium and lead were most influenced 

by sediment leaching processes as 85 to 90 percent of these 

trace elements generally are removed as indicated by residual 

sediment concentrations that were 10 to 15 percent (fig. 9) 

of the concentration in the untreated sediment samples. This 

effect is less pronounced for copper and zinc where 66 to 

78 percent of copper and zinc concentrations are removed 

by exposure to the hydroxylamine hydrochloride reagent 

yielding residual sediment fractions of copper and zinc (22 

to 33 percent), which are over twice those for cadmium and 

lead. Copper and zinc are the trace elements of concern 

that have the greatest concentration in the interior matrix of 

the slag particles, which may partially explain their higher 

concentration in the residual fraction. Arsenic was present 

mostly in the residual fraction and not as greatly associated 

with the surface of the sediment particles as were cadmium, 

copper, lead, and zinc. 

Metallurgical Slag in Sediments of 

Lake Roosevelt

Slag particles have been widely deposited in the riverbed 

and along the banks of the upper and transitional reaches 

of Lake Roosevelt, particularly between Northport and the 

International Boundary. Slag particles make up from 70 to 

90 percent by weight of the sand-sized particles of a black 

sand beach at RM 743 near the International Boundary (fig. 

10). Particles of metallurgical slag have been found farther 

downstream in sediments of the Columbia River and Lake 

Roosevelt although easily identifiable slag grains diminish in 

number and size downstream of Northport. Slag particles can 

be readily distinguished from natural sediment grains of the 

Columbia River by a combination of distinctive morphology 

and physical features. The slag particles are sand size or 

smaller, black in color, and often have an iridescent sheen (fig. 

11A). The surface texture of relatively unweathered particles is 

smooth, glassy, with a lustrous appearance while the surface of 

weathered grains has a dull-etched appearance. Slag particles 

have a distinctive morphology resulting from the combination 

of rounded and angular features often with needle-like 

projections, conchoidal fracture patterns, and small cavities 

or vugs (fig. 11B). Vugs generally are empty in unweathered 

particles while vugs in weathered particles are often filled 

with oxide precipitates, which may encrust much of weathered 

particles. Slag grains in thin section often contain large voids 

(fig. 11C); particles are opaque to transmitted light but may 

transition to amber at the extreme tip of pointed projections. 

The matrix of slag particles is a glassy calcium-iron-silicate 

with varying amounts of aluminum. Internal structures 

within the glassy matrix include various mineral phases 

and rounded metallic-sulfide blebs or prills (figs. 12A, 12B, 

12C) containing copper or lead; with associated metals such 

as antimony and arsenic (Bart Canon, Microlab Northwest, 

Seattle, Washington, written commun., 2001). The density of 

slag particles varies, generally exceeding 2.9 g/cm3, however, 

some slag particles, which may have large voids, were 

observed floating on the water surface near the shore. 

The general trace-element composition of slag discharged 

to the Columbia River is reported to vary considerably with 

typical concentrations of weight percent of <0.1 percent for 

lead, (<1,000 mg/kg); 3 percent for zinc (30,000 mg/kg); 

<0.01 percent cadmium (<100 mg/kg); and about 1 percent 

copper (10,000 mg/kg) (Cominco, 1991). G.J. Gawryletz 

(Cominco Ltd., written commun., 1998) reported substantially 

larger concentrations of zinc and lead, 12 and 2 percent, 

respectively, from residual slag deposits along the Columbia 

River following demolition of the slag launder and these 

concentrations were about three times larger than earlier 

reported concentrations. These data confirm that trace-element 

concentrations vary in Trail smelter slag. 

Readily available reported chemical analysis of slag 

including elements other than the six trace elements of concern 

include the three analyses reported by Nener (1992) in which 

the slag was sampled prior to release to the environment. 

Majewski and others (2003) provided an analyses of ‘riverine 

slag’; a sample collected along the riverbank containing both 

slag and natural river sediments. A similar sample collected 

from the beach at RM 743 (RSS-743) was analyzed for this 

study; the sample was sieved and sorted using a binocular 

microscope in an attempt to remove as much of the non-slag 

material as possible. Analysis of the sorted slag sample 

(RSS-743) is included in table 5 (after data for CCR-705). 

The slag particles collected from a beach near the 

Columbia River International Boundary Auxiliary Gage at 

RM 743 is physically and chemically similar to the 

description of metallurgical slag discharged from the Trail 

smelter (Cominco, 1991). Bulk chemical compositions were 

determined for the polished interior surface of individual 

slag particles using a scanning electron microscope equipped 

with an energy-dispersive X-ray spectrometer (SEM/EDS). 

Median element-weight percentages of the slag determined by 

SEM/EDS were 37 for iron, 10 for calcium, 2.8 for aluminum, 

2.6 for zinc, 1.3 for sodium, 0.8 for magnesium, 0.6 for 

manganese, 0.5 for copper, and 0.4 for potassium. 

34 Vertical Distribution of Trace Elements and Metallurgical Slag in Sediments, Lake Roosevelt, Washington, 2002
The SEM/EDS measurements of elemental 

concentrations RSS-743 matched closely the reported 

chemical analysis of slag discharged to the Columbia River 

by the Trail smelter (Nener, 1992) and the chemical analysis 

of the slag sample RSS-743 as shown in the boxplots in 

figure 13. The SEM/EDS analysis was determined from the 

measurement of 22 individual grains, whereas the elemental 

composition of slag from the Trail smelter was determined 

from an acid digest of three samples of fresh slag collected 

during a single day (Cominco, 1991; Nener, 1992). The 

comparison was limited to those elements determined by the 

SEM/EDS that were present in the sample at concentrations 

greater than 0.5 percent. The nine elements from all analyses 

were a close match considering differences in sample 

representation and methods of analysis (fig. 13). The close 

match between the suite of elements in the analysis of 

individual slag particles and bulk chemical analysis of slag 

also provided a method to confirm the identity of slag particles 

in downstream reaches of the reservoir.

Sediment particles isolated from selected sample intervals 

from the three upstream cores, CCR-668 interval 95-100; 

CCR-692 interval 30-32 cm, and CCR-705 interval 14-16 cm 

were classified as slag grains based on physical characteristics, 

density, and chemical composition. The largest particles, on 

the order of 1-2 mm that were most similar to those from 

the Columbia River sand bar at RM 743 (RSS-743), were 

from the interval 100-105 cm below the upper surface of 

CCR-668 (sediment-water interface). Slag particles in cores 

CCR-692 and CCR-705 were on the order of 0.05 to 0.1 mm, 

which was consistent with the predominant particle size of 

these sediments. The trace-element profiles for core CCR668 indicate that the interval in which the slag particle was 

identified was in a section of the profile affected by landslides, 

thus, the slag in this interval likely was reworked material 

that had been transported to this area of the reservoir prior to 

construction of Grand Coulee Dam. Although these particles 

had similar color, shape, and optical properties to slag material 

from the gage location at RM-743, the surface appearance 

typically was more weathered, without the glassy-lustrous 

appearance, but retained some of the iridescent sheen. 

The chemical composition determined by SEM/EDS 

of the surface of slag particles from core CCR-668 closely 

matched the slag particles from the recent beach deposit 

(sample RSS-743) except that the concentration of calcium 

typically was lower by as much as 70 percent in slag from core 

CCR-668 (fig. 14). Further SEM examination showed that the 

concentration of calcium on the surface of the slag particles 

from RSS-743 was intermediate between the relatively 

unweathered composition determined for the interior matrix of 

slag from RSS-743 and weathered surface of slag particles that 

had been buried with the reservoir sediments for some 

20 to 40 years. 

Figure 10. Black sand beach composed of 70 to 90 percent slag particles deposited near Columbia River gaging station at river 

mile 743, Washington.

Trace Elements in Pore Water and Sediment 35
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Figure 11. Slag particles (RS-743) identified in sediment from Lake Roosevelt and the upper Columbia River, Washington.

36 Vertical Distribution of Trace Elements and Metallurgical Slag in Sediments, Lake Roosevelt, Washington, 2002
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The decrease in calcium is consistent with weathering of 

basaltic-volcanic glass, as calcium is often the most readily 

leached major element from basaltic glass (Eggleton and 

others, 1987). Calcium was determined to be selectively 

mobilized from massive lead-zinc slag exposed to natural 

weathering in Czechoslovakia for more than 

100 years (Ettler and others, 2001). The surface texture and 

morphology, observed by SEM, of slag-like particles from 

the core sediments were marked by a flaky appearance and 

the precipitation of iron-oxide (figs. 15A and 15B). The 

dimensions of the surficial flakes typically were 20 to 

50 microns across and 2 to 5 microns thick and likely result 

from the development of exfoliation lamina on the surface of 

slag particles caused by the hydration of glassy slag material 

as described by Freidman and others (1966) and Morganstein 

and others (1999).

Glassy slag deposited in the sediments of Lake Roosevelt 

shows definite signs of undergoing hydration and chemical 

weathering, rather than being chemically stable as described 

by Cominco (1991). Fourteen of eighteen slag grains from 

core CCR-668 that were examined with just the SEM showed 

signs of surficial weathering by the development of exfoliation 

flakes (figs. 15A-15D). There also were differences in the 

chemical compositions of the interior and exterior surfaces 

of the weathered slag material (fig. 16). SEM/EDS was used 

to measure the chemical composition of six locations on an 

interior surface exposed by the removal of an exfoliation flake 

and exterior surfaces of the slag grain shown in figure 12B. 

On the interior surface where the flake had been removed, 

the concentrations of calcium, iron, and zinc were larger 

compared to the outer surface. Concentrations of silicon, 

oxygen, potassium, aluminum, and sodium were higher on the 

exterior surface than on the interior surface. The distribution 

of these elements is consistent with weathering processes as 

calcium and iron are often mobile elements removed during 

chemical weathering while silicon, aluminum, and oxygen 

are more recalcitrant elements whose concentrations become 

larger in the residual weathered material. Further evidence 

of slag weathering is the development of weathering rinds, 

typically about 20 to 100 microns thick, as shown in slag 

grains below the lacustrine sediments south of French Rocks, 

RSS-685 (figs. 15C and 15D). Weathering rinds were not 

observed in the polished cross section of the unweathered slag 

particles collected from the beach deposit near the gage site at 

RM 743 (RSS-743) (fig. 12B).

Figure 11.—Continued

Trace Elements in Pore Water and Sediment 37
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Figure 12. Scanning electron microscope (backscatter images) of unweathered slag particles from Lake Roosevelt, 

Washington.

38 Vertical Distribution of Trace Elements and Metallurgical Slag in Sediments, Lake Roosevelt, Washington, 2002
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Figure 12.—Continued

Trace Elements in Pore Water and Sediment 39
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Figure 13. Trace-element concentrations determined by SEM/EDS of slag particle (sample RSS-743) and reported concentrations 

from previous studies determined by acid digestion and instrumental analysis, Lake Roosevelt, Washington.

40 Vertical Distribution of Trace Elements and Metallurgical Slag in Sediments, Lake Roosevelt, Washington, 2002
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Figure 14. Trace-element concentrations determined by SEM/EDS of recently deposited slag particles and slag grains from core 

sediments, Lake Roosevelt, Washington.

Trace Elements in Pore Water and Sediment 41
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Figure 15. Scanning electron microscopic (backscatter images) of weathered slag particles from Lake Roosevelt, 

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42 Vertical Distribution of Trace Elements and Metallurgical Slag in Sediments, Lake Roosevelt, Washington, 2002
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Trace Elements in Pore Water and Sediment 43
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44 Vertical Distribution of Trace Elements and Metallurgical Slag in Sediments, Lake Roosevelt, Washington, 2002
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Figure 16. Trace-element concentrations determined by SEM/EDS of outer surface of slag particles and inner surface 

exposed by removal of exfoliation flake, Lake Roosevelt, Washington.

Trace Elements in Pore Water and Sediment 45
Relative Impacts of Slag and Liquid 

Effluent Discharge on Trace-Element 

Concentrations in Bed Sediment

Multiple lines of evidence indicate that the influence 

of slag on trace-element concentrations in the sediments of 

the middle and lower reaches of Lake Roosevelt are likely 

secondary to the influences of liquid effluent discharges. 

First, the low percentages of cadmium and lead, and to a 

lesser degree zinc and copper, present in the residual of the 

leached sediment samples indicates that these trace elements 

are predominantly associated with the sediment grain surface 

rather than the interior matrix of the sediment grains. If slag 

were the primary source of these trace elements, most of the 

mass of the element would be in the interior matrix of the slag 

particles and not susceptible to leaching with hydroxylamine 

hydrochloride reagent. 

Second, the widespread and approximately concurrent 

decreases in trace-element concentrations observed in the 

trace-element profiles above the 1964 horizon in the Columbia 

River cores are more consistent with trace-element discharges 

in the liquid effluent than discharges in slag material. Trace 

elements sorbed to very fine-grained sediment surfaces 

typically originate as dissolved trace elements or trace 

elements bound to or associated with colloidal material such 

as that discharged in the liquid effluent of the Trail smelter. 

Dissolved and colloidally associated trace elements are more 

easily transported throughout the length of the reservoir 

than slag that is discharged as predominantly sand-size 

particles and would require more time for even the smaller 

size fractions to be transported to the lower reaches of the 

reservoir. Transport of most of the slag particle-size fractions 

within the middle and lower reaches of the reservoir is limited 

to times when flow is great enough to transport larger grain 

sizes. As a result, the effects of slag discharge on traceelement concentrations in the accumulated bed sediments 

would take longer to be observed in the lower reaches of the 

reservoir and would likely be less pronounced. 

Although slag was observed below lacustrine bed 

sediments at RM 680 and in core CCR-668, the presence of 

large slag deposits like that shown in figure 7 in or below 

the lacustrine sediments of the reservoir is most likely an 

uncommon occurrence. Direct observation of slag grains 

in reservoir sediments generally was confined to the upper 

reaches of the reservoir above RM 700. Using a point-count 

microscopic examination, Bortleson and others (1994) 

estimated that slag made up about one-half of the sediment 

sample from RM 745 near the International Boundary, about 

28 percent of the sediment at RM 738, and only about 

5 percent of the sediment at RM 730. Likewise, Bart Canon 

(Northwest Microprobe, written commun., 2002) estimated 

that while slag composed a substantial fraction of sediments 

from near RM 744 and RM 748, slag was a negligible fraction 

of sediments from near RM 723.

Third, the timing of most of the major decreases in 

trace-element concentrations occurring within the traceelement profiles occur throughout the period following the 

CS-137 peak associated with the mid-1960s. The more gradual 

reduction observed in the trace-element profiles from the 

cores also is more consistent with the trend in the reduction of 

trace-element loading in liquid effluent (fig. 7) than compared 

to trend in historical reductions of slag discharge. This is 

most clearly observed for mercury and cadmium and to a 

lesser degree lead, which are very minor components of slag 

(Cominco, 1991), but substantial components of the liquid 

effluent discharge (British Columbia Ministry of Environment, 

1976). Zinc is a substantial component of both liquid effluent 

and slag material discharged by the Trail smelter. 

The concentration of copper in bed sediments may be 

a useful indicator of the presence of slag in sediments from 

Lake Roosevelt. Copper is distinctive among the six trace 

elements of concern because it is discharged by the Trail 

smelter primarily as slag. Using estimates of slag percentage 

in sediments from the upper reach of the reservoir (Bortleson 

and others, 1994) and assuming that all copper reported in the 

measured concentration for the corresponding samples is due 

to the presence of slag, the calculated concentration of copper 

in slag at those locations would be expected to range from 

0.7 to 1.5 percent. This is consistent with the measured and 

reported range of copper concentrations in slag from the Trail 

smelter of about 0.6 to 1 percent. If the presence of elevated 

copper concentration in sediments is largely the result of slag 

particles (a conservative assumption based on the sediment 

leaching data), sediment samples with less than 125 mg/kg of 

copper would be expected to contain less than 1 percent slag 

in addition to a background concentration of about 25 mg/kg 

of copper. Applying this reasoning to the longitudinal gradient 

of copper in Lake Roosevelt sediments observed by Majewski 

and others (2003), and Bortleson and others (1994), the major 

influence of slag in sediments is limited to reaches upstream 

of about RM 687. Thus, the trace-element concentrations of 

zinc, lead, cadmium, mercury and to a lesser extent arsenic in 

sediments in the lower and middle reaches of the reservoir are 

largely due to the input from liquid effluent discharged to the 

Columbia River, which can easily be transported the length of 

the reservoir as dissolved or colloidal material. 

46 Vertical Distribution of Trace Elements and Metallurgical Slag in Sediments, Lake Roosevelt, Washington, 2002
Summary and Conclusions

In 2002, the U.S. Geological Survey conducted a study 

of Lake Roosevelt to collect information on the vertical 

distribution of trace elements within the accumulated bed 

sediments and pore water of Lake Roosevelt, the 217-kmlong impoundment of the Columbia River upstream of 

Grand Coulee Dam, Washington. Vertical distributions of 

trace-element concentrations were determined from six 

sediment cores collected in September 2002. The analysis of 

cesium-137 data indicate that two sediment cores contained 

sedimentary records extending to the initial reservoir filling in 

1941 and the remaining four cores contained at least 

60 percent of the sedimentary record. Pore-water samples 

were collected and analyzed from the top 10 cm at the three 

upstream core sites.

Concentrations of the trace elements of concern, arsenic, 

cadmium, copper, lead, mercury, and zinc, varied greatly in 

the sediment core profiles, often covering a range of 5 to 

10 fold. Maximum concentrations in sediment samples 

were as high as 2,200 milligrams per kilogram (mg/kg) 

for zinc, 920 mg/kg for lead, and 250 mg/kg for copper, 

with median concentrations of 970, 260, and 53 mg/kg, 

respectively. Concentrations of arsenic, cadmium, and 

mercury were lower. Maximum concentrations were as high 

as 34 mg/kg for arsenic, 23 mg/kg for cadmium, and 

2.8 mg/kg for mercury, with median concentrations of 13, 

7.5, and 0.58 mg/kg, respectively. Concentrations of cadmium 

and mercury exceeded the upper range of reference sediments 

by 10 times or more in 77 and 47 percent of the samples 

analyzed, respectively. 

Concentrations of lead and zinc exceeded reference 

sediments by 10 times in less than 25 percent of the samples 

analyzed. Prominent temporary decreases in the concentrations 

of cesium-137 and trace elements indicate an influx of 

sediments from landslides. Of these trace elements of concern, 

concentrations of arsenic and copper were least elevated above 

concentrations in reference sediments. All samples exceeded 

cleanup guidelines adopted by the Colville Confederated 

Tribes for cadmium, lead, and zinc and more than 70 percent 

of samples exceeded cleanup guidelines for mercury, arsenic, 

and copper. Although 100 percent of samples exceeded 

sediment guidelines for cadmium, lead, and zinc, surficial 

concentrations of arsenic, copper, lead, and mercury in some 

cores were less than the sediment-quality guidelines.

Trace-element concentrations were highest beneath 

surficial sediments, typically in the lower one-half of each 

profile. With the exception of copper, the trace-element 

profiles of the five cores collected along the pre-reservoir 

Columbia River channel typically showed trends of 

decreasing concentrations from the 1964 sediment horizon 

to the sediment-water surface. Along the longitudinal profile 

of the reservoir, surficial concentrations of zinc, copper, 

lead, cadmium, and mercury showed trends of decreasing 

concentration, while concentrations of arsenic tended to 

increase slightly downstream. Trace-element concentrations 

and profiles in sediments from the Spokane Arm of the 

reservoir showed distinct differences compared to the 

similarities observed among the cores from along the 

pre-reservoir Columbia River. These differences likely are 

due to the greater influence of sediment inflow from the 

Coeur d’Alene basin to that portion of the reservoir.

Overall, the depth concentration profiles typically show 

maximum concentrations of arsenic, cadmium, lead, mercury, 

and zinc often occurred in the lower to mid sections (closer to 

the bottom) of the trace-element profile and the concentrations 

of copper often were highest (closer to the surface) in the 

trace-element profiles. The concentration profiles for arsenic, 

cadmium, lead, zinc, and to a lesser extent mercury, also 

clearly show decreasing concentrations in more recently 

deposited sediments throughout the reservoir as reported by 

Majewski and others (2003). However, the concentration 

profiles for copper generally show trends of increasing 

concentrations in more recent sediments with the exception 

of core CCR-692. Within individual cores, the concentration 

profiles of arsenic, cadmium, copper, lead, mercury and zinc 

showed similar patterns of relative concentrations. Variation in 

the concentration of zinc, lead, cadmium, and mercury were 

consistent to the extent that concentration profiles were often 

near parallel. In some core intervals, the influx of sediments 

from bank material accentuated the near parallel concentration 

profiles.

Concentrations of dissolved arsenic, cadmium, copper, 

lead and zinc in pore waters were often higher than ambient 

dissolved concentrations measured in Columbia River water 

and thus may be a source of trace elements to the overlying 

surface water. The limited pore-water concentration data was 

inconclusive with respect to the extent of remobilization of 

trace metals from buried sediments to the overlying water. 

Additional information is needed on possible seasonal 

variation in pore concentrations that may be affected by 

the changing pool elevation in the reservoir. The leaching 

experiment indicated that most of the mass of trace elements 

associated with the contaminated sediments is associated with 

the surface of the sediment particle where it is more accessible 

to physical, chemical, and biological processes that could 

remobilize the trace element into the overlying water column. 

Summary and Conclusions 47
Selected samples were analyzed for the presence of 

metallurgical slag, a trace element-rich byproduct of metals 

smelting processes, which was discharged into the Columbia 

River by a smelter in Trail, British Columbia, upstream of 

the reservoir prior to 1995. Particles that had physical and 

chemical characteristics of slag discharged to the Columbia 

River were present in the sediments of Lake Roosevelt. 

Particles of slag were isolated from three cores based on 

their distinctive physical characteristics, appearance (smooth, 

glassy-lustrous, black in color, and being both angular and 

rounded in shape), and chemical composition measured 

using a scanning electron microscope equipped with an 

energy dispersive spectrometer (SEM/EDS). The chemical 

composition of the interior matrix of slag collected from 

a black-sandy beach near the International Border closely 

approximated the reported elemental concentrations of fresh 

smelter slag. Slag particles isolated from the core sediments 

appeared more weathered due to the lack of the glassy-lustrous 

appearance; however, their chemical composition closely 

matched the composition of unweathered particles except that 

the concentration of calcium was roughly 20 percent smaller. 

SEM/EDS examination of the morphology of the surface of 

many of the slag particles from the core sediments showed 

the development of exfoliation flakes suggesting that the 

glassy slag material was undergoing hydration and chemical 

weathering. 

Slag, while common in the uppermost reaches of the 

reservoir above river mile 720, may be present only in minor 

amounts in sediments of the lower and mid reaches of the 

reservoir. Trace elements in sediments in the lower and mid 

reaches of the reservoir are thus largely due to the liquid 

effluent discharged to the Columbia River, which can easily be 

transported the length of the reservoir. Relative concentrations 

of trace elements in the cores from those reaches of the 

reservoir resemble relative loading of trace elements from the 

liquid effluent, further supporting that conclusion. 

References Cited

Arbogast, B.F. (ed.), 1996, Analytical methods manual for 

the Mineral Resource Surveys Program: U.S. Geological 

Survey Open-File Report 96-525, 248 p.

Bortleson, G.C., Cox, S.E., Munn, M.D., Schumaker, R.J., 

Block, E.K., Bucy, L.R., and Cornelius, S.B., 1994, 

Sediment-quality assessment of Franklin D. Roosevelt Lake 

and the upstream reach of the Columbia River, Washington, 

1992: U.S. Geological Survey Open-File Report 94-315, 

130 p.

British Columbia Ministry of Environment, 1976, Kootenay 

Air and Water Quality Study Phase I: Water Quality in the 

Lower Columbia River Basin, Victoria, British Columbia, 

234 p. 

British Columbia Ministry of Environment, 1979, Kootenay 

Air and Water Quality Study Phase II: Water Quality in the 

Lower Columbia River Basin, Victoria, British Columbia, 

238 p. 

Chao, T.T., and Zhou, Liyi, 1983, Extraction techniques for 

selective dissolution of amorphous iron oxides from soils 

and sediments: Soil Science Society of America Journal, 

v. 47, no. 2, p. 225-232.

Charles, M.J., and Hites, R.A., 1987, Sediments as archives 

of environmental pollution trends: In Hites, R.A. and 

Eisenreich, S.J., eds., Sources and Fates of Aquatic 

Pollutants, Advances in Chemistry Series Number 216: 

Washington, DC, American Chemical Society, p. 365-389.

Colville Confederated Tribes, 2003, Sediment cleanup levels 

for the protection of human health and sediment dwelling 

organism: Nespelum, Washington, Colville Confederated 

Tribes, in Colville Tribe Hazardous Substances Control Act, 

Appendix C, p. 25-28.

Commeau, J.A., Poppe, L.J., and Commeau, R.J., 1992, 

Separation and identification of the silt-sized heavy-mineral 

fraction of sediments: U.S. Geological Survey Circular 

1071, 13 p.

Cominco, 1991, Slag disposal options: environmental and 

engineering studies: Trail Operations-Cominco Metals, 

Trail, British Columbia, 24 p., with 3 appendixes.

Cominco, 1992, Cominco Trail Operations Environment 

Report: Trail Operations-Cominco Metals, Trail, British 

Columbia, 24 p. 

Cominco, 2001, Trail operations environmental performance 

review of the new KIVCET lead smelter and elimination 

of slag discharge: Assessment of Columbia River receiving 

waters, Summary: Trail Operations-Cominco Metals, Trail, 

British Columbia, 11 p. 

Crusius, John, and Anderson, R.F., 1995, Sediment focusing in 

six small lakes inferred from radionuclide profiles: Journal 

of Paleolimnology, v. 13, p. 143-155.

Derewetzky, R.F., Funk, W.H., and Juul, S.T.J., 1994, Lake 

Franklin D. Roosevelt: Water Quality Retrospective 

Analysis: State of Washington Water Research CenterWashington State University, Report 90, Pullman, 

Washington, p. 152.

Eggleton, R.A., Foudoulis, Chris, and Varkevisser, Dane, 

1987, Weathering of basalt: Changes in Rock Chemistry 

and Mineralogy: Clays and Clay Minerals, v. 35, no. 3, 

p. 161-169.

Ettler, Vojtech, Legendre, Olivier, Bodenan, and Touray, JeanClaude, 2001, Primary phases and natural weathering of 

old lead-zinc pyrometallurgical slag from Czech Republic: 

Canadian Mineralogist, v. 39, p. 873-888.

Friedman, Irving, Smith, R.L., and Long, W.D., 1966, 

Hydration of natural glass and the formation of perlite: 

Geological Society of America Bulletin, v. 77, p. 323-328.

G3 Consulting, Ltd., 2001, Assessment of Columbia River 

receiving waters, Final Report: Prepared for Teck Cominco 

Metals, Ltd., Trail Operations, by G3 Consulting, Ltd., 

Burnaby, British Columbia, 183 p.

48 Vertical Distribution of Trace Elements and Metallurgical Slag in Sediments, Lake Roosevelt, Washington, 2002
Grosbois, C.A., Horowitz, A.J., Smith, J.J., and Elrick, 

K.A., 2001, The effect of mining and related activities on 

the sediment-trace element geochemistry of Lake Coeur 

d’Alene, Idaho, USA. Part III. Downstream effects: the 

Spokane River Basin: Hydrological Processes, v. 15, no. 5, 

p. 855-875. 

Horowitz, A.J., Elrick, K.A., and Cook, R.B., 1993, Effect of 

mining and related activities on the sediment-trace element 

geochemistry of Lake Coeur d’Alene, Idaho, USA. Part I. 

Surface sediments: Hydrological Processes, v. 7, p. 403-

423.

Johnson, A.J., Norton, Dale, Yake, W., and Twiss, S., 1988 

[1989], An assessment of metals contamination in Lake 

Roosevelt: Washington State Department of Ecology, 

Olympia, Washington, 71 p. 

Johnson, A., Norton, Dale, Yake, W., and Twiss, S., 1990, 

Transboundary metal pollution of the Columbia River 

(Franklin D. Roosevelt Lake): Bulletin of Environmental 

Contamination and Toxicology, v. 45, 7 p. 703-710.

Jones, F.O., Embody, D.R., Peterson, W.L., and Hazelwood, 

R.M., 1961, Landslides along the Columbia River valley, 

northeastern Washington, with a section on seismic surveys: 

U.S. Geological Survey Professional Paper 367, 98 p.

Kelly, V.J., Hooper, R.P., Aulenbach, B.T., and Janet, Mary, 

2001, Concentrations and annual fluxes for selected 

water-quality constituents from the USGS National Stream 

Quality Accounting Network (NASQAN), 1996-2000: U.S. 

Geological Survey Water-Resources Investigations Report 

01-4255 URL: http://water.usgs.gov/nasqan/progdocs/

wri014255/results/data/sed.dat, accessed March 2004.

Kiver, E.P., and Stradling, D.R., 1995, Geology of the Franklin 

D. Roosevelt Reservoir Shoreline: Glacial geology, terraces, 

landslides, and lineaments: Grand Coulee, Washington, U.S. 

Bureau of Reclamation, Pacific Northwest Region, 147 p. 

Levinson, A.A., 1974, Introduction to exploration 

geochemistry: Calgary, Canada, Applied Publishing, Ltd., 

612 p. 

Lowe, T.P., May, T.W., Brumbaugh, W.G., and Kane, D.A., 

1985, National contaminant biomonitoring program—

Concentrations of seven elements in freshwater fish, 

1978-1981: Archives of Environmental Contamination and 

Toxicology, v. 14, p. 363-388.

Lottermoser, B.G., 2002, Mobilization of heavy metals from 

historical smelting slag dumps, north Queensland, Australia:

Mineralogical Magazine, v. 66, p. 475-490.

Lydon, J.W., 2000, A synopsis of the current understanding 

of the geological environment of the Sullivan Deposit, in 

J.W. Lydon, Hoy, T., Slack, J.F., and Knapp, M.E. [eds.], 

Geological Environment of the Sullivan Deposit, British 

Columbia, Chapter 3: Geologic Association of Canada 

Mineral Deposits Division Special Publication No. 1, 

p. 12-31. 

MacDonald, D.D., Ingersoll, C.G., and Berger, T.A., 2000, 

Development and evaluation of consensus-based sedimentquality guidelines for freshwater ecosystems: Archive of 

Environmental Contamination and Toxicology, v. 39, 

p. 20-31. 

Majewski, M.S., Kahle, S.C., Ebbert, J.C., and Josberger, 

E.G., 2003, Concentrations and distribution of slag-related 

trace elements and mercury in fine-grained beach and 

bed sediments of Lake Roosevelt, Washington, AprilMay, 2001: U.S. Geological Survey Water-Resources 

Investigations Report 03-4170, 29 p. 

Mills, J.W., 1977, Zinc and lead ore deposits in carbonate 

rocks, Stevens County, Washington: Washington State 

Department of Natural Resources-Division of Geology and 

Earth Resources, Olympia, WA Bulletin 70, 171 p.

Morganstein, M.E., Wicket, C.L., and Barkatt, Aaron, 1999, 

Considerations of hydration-rind dating of glass artifacts: 

Alteration morpholodies and experimental evidence of 

hydrogeochemical soil-zone pore water control: Journal of 

Archaeological Science, v. 26, p. 1193-1210.

Munn, M.D., 2000, Contaminant trends in sport fish from 

Lake Roosevelt and the upper Columbia River, Washington, 

1994-1998: U.S. Geological Survey Water-Resources 

Investigations Report 00-4024, 12 p.

Munn, M.D., Cox, S.E., and Dean, C.J., 1995, Concentrations 

of mercury and other trace elements in walleye, smallmouth 

bass, and rainbow trout in Franklin D. Roosevelt Lake 

and the upper Columbia River, Washington, 1994: U.S. 

Geological Survey Open-File Report 95-195, 35 p.

Nener, Jennifer, 1992, Survival and water-quality results of 

bioassays on five species of aquatic organisms exposed to 

slag from Cominco’s Trail operation: Fisheries and Oceans 

Canada, Vancouver, British Columbia, Canada, 20 p. plus 

tables and appendixes. 

NORECOL Environmental Consultants Ltd,, 1989, Statistical 

analysis of metal levels in fish of the Columbia River near 

the International Boundary, 1980 to 1988: NORECOL 

Environmental Consultants Ltd,, Vancouver, British 

Columbia, p. 30.

Orlob, G.T., and Saxton, W.W., 1950, Mining and mill waste 

pollution in the Upper Columbia River Basin and Lake 

Roosevelt: Washington Pollution Control Commission, 

Olympia, 12 p.

Parsons, M.B., Bird, D.K., Einaudi, M.T., Alpers, C.N., 

2001, Geochemical and mineralogical controls of trace 

element release from the Penn Milebase-metal slag dump, 

California: Applied Geochemistry, v. 16, p. 1567-1593.

Piatak, N.M., Seal, R.R., and Hammarstorm, J.M., 2004, 

Mineralogical and geochemical controls on the release 

of trace elements from slag produced by base- and 

precious-metal smelting at abandon mine sites: Applied 

Geochemistry, v. 19, p. 1039-1064.

References Cited 49
Reyes, Julito, Goodarzi, Fari, Sanei, Hamed, Hilts, Steven, 

and Duncan, W.F., 2004, Concentrations of elements in the 

stream sediments of Trail, B.C. and surrounding area and 

the Natural Background Concentrations: Geological Survey 

of Canada, Environmental Study Group, Calgary Alberta, 

58 p. 

Ritchie, J.C., and McHenry, J.R., 1990, Application of 

radioactive cesium-137 for measuring soil erosion and 

sediment accumulation rates and patterns: A review: Journal 

of Environmental Quality, v. 19, p. 215-233.

Rose, A.W., Hawkes, H.E., and Webb, J.S., 1979, 

Geochemistry in mineral exploration: London, Academic 

Press Ltd., 2nd edition, 657 p.

Shacklette, H.T., and Boerngen, J.G., 1984, Element 

concentrations in soils and other surficial materials of 

the conterminous United States: U.S. Geological Survey 

Professional Paper 1270, 105 p.

Sheehan, S. W., and Lamb, M, 1987, Water Chemistry of the 

Columbia and Pend d’Oreille Rivers near the International 

Border: Environment Canada, Inland Waters and Lands, 

Pacific and Yukon Region, Vancouver, British Columbia, 

312 p.

Sigma Engineering Ltd., 1987, Statistical analysis of water 

chemistry data from the Columbia and Pend D’Oreille 

Rivers: Vancouver, British Columbia, Environment Canada, 

Inland Water Directorate, Water Quality Branch, Report 

E5496, 30 p. with 5 appendixes

Smith, A.L., 1987, Levels of metals and metallothionein in 

fish of the Columbia River near the international boundary: 

Environment Canada & British Columbia Ministry of 

Environment, Victoria, British Columbia 133 p. 

Teck-Cominco, 2002, Annual Information Form: March 1, 

2002: Vancouver, British Columbia, Teck Cominco Limited, 

19 p. http://www.teckcominco.com/investors/reports/aifcirc/tc-aif-01.pdf, accessed December 2003.

U.S. Bureau of Reclamation, 2001, Franklin D. Roosevelt 

Lake—2001 Landslide Inspection Report, Grand Coulee 

Power Office: Grand Coulee, Washington, 40 p.

U.S. Department of Energy-Nevada Operations Office, 

December 2000, United States Nuclear Test July 1945 

through September 1992: DOS/NV—209-REV115, 189 p.

U.S. Environmental Protection Agency, 2000, Upper 

Columbia River/Lake Roosevelt river mile 597 to 745—

Preliminary assessment report, Washington: TDD: 99-10-

0002, U.S. Environmental Protection Agency Superfund 

Technical Assessment and Response Team, variously 

paginated.

U.S. Environmental Protection Agency, 2003, Upper 

Columbia River Expanded Site Investigation Report, 

northeast Washington: TDD: 01-02-0028, U.S. 

Environmental Protection Agency Superfund Technical 

Assessment and Response Team, variously paginated.

Van Metre, P.C., Callender, E., and Fuller, C.C., 1997, 

Historical trends in organochlorine compounds in river 

basins identified using sediment cores from reservoirs: 

Environmental Science and Technology, v. 31, no. 8, 

p. 2339-2344. 

Washington State Department of Natural Resources, 

Division of Geology and Earth Resources: The geology of 

Washington-Okanogan Highland, http://www.dnr.wa.gov/

geology/okanogan.htm, accessed November 2003.

50 Vertical Distribution of Trace Elements and Metallurgical Slag in Sediments, Lake Roosevelt, Washington, 2002
CCR-624

Depth 

interval 

(cm)

Cesium-137

(pCi/g) Aluminum Antimony Arsenic Barium Beryllium Bismuth Cadmium Calcium Carbonate(percent)

Organic

carbon

(percent)

0-3 0.15 74,000 2.4 12 840 2.2 0.53 2.2 13,000 0.02 1.4

3-6 – 73,000 3.1 10 820 2.3 .54 2.1 13,000 .03 1.4

9-12 .38 76,000 5.2 14 940 2.5 .67 7.6 11,000 .03 1.6

12-15 .46 75,000 3.3 14 950 2.4 .70 12 11,000 .04 1.6

18-21 – 74,000 4.5 14 960 2.3 .69 10 15,000 .26 1.2

21-24 .73 73,000 4.9 17 1,100 2.3 .74 11 17,000 .36 1.2

27-30 1.6 78,000 5.2 22 1,000 2.1 .82 16 18,000 .39 1.6

30-33 .62 70,000 4.4 13 760 1.9 .56 8.0 16,000 .12 1.6

33-35 .38 69,000 3.3 13 740 1.8 .49 5.4 16,000 .1 1.6

36-39 – 77,000 9.8 9.0 880 2.3 1.5 18 17,000 – –

39-42 – 80,000 6.9 11 990 2.5 1.9 23 16,000 – –

42-45 – 94,000 5.6 21 920 2.6 1.4 18 14,000 .13 1.8

45-48 – 81,000 2.9 18 840 2.5 1.1 15 12,000 .06 1.8

Depth

interval

(cm)

Cerium Cesium Chromium Cobalt Copper Gallium Iron Lanthanum Lead Lithium Magnesium

0-3 100 6.4 64 16 49 18 46,000 58 90 38 12,000

3-6 110 6.4 62 16 70 19 42,000 65 110 39 12,000

9-12 110 7.1 91 17 74 19 45,000 110 240 42 13,000

12-15 100 7.2 94 16 67 19 43,000 100 280 42 13,000

18-21 100 6.9 74 15 47 18 40,000 76 300 41 15,000

21-24 120 6.7 74 15 51 18 39,000 91 400 40 16,000

27-30 110 6.5 75 18 60 18 44,000 100 540 40 13,000

30-33 84 5.0 50 14 43 17 40,000 57 320 34 11,000

33-35 86 4.6 46 15 37 17 40,000 53 250 30 10,000

36-39 – 6.0 64 17 66 20 48,000 49 600 37 12,000

39-42 – 7.0 80 18 88 20 46,000 58 920 42 14,000

42-45 80 7.6 93 21 86 22 55,000 55 680 45 14,000

45-48 76 7.0 67 19 66 19 48,000 50 450 39 15,000

Table 5. Vertical distribution of major and trace-element concentrations in sediment core subsections from Lake Roosevelt, Washington, September 2002. 

[Concentrations of trace elements are given in micrograms per kilogram unless otherwise noted. Abbreviations: cm, centimeter; pCi/g, picoCuries per gram;

<, less than; –, no data]

Table 5 51
CCR-624—Continued

Depth 

interval 

(cm)

Manganese Mercury Molybdenum Nickel Niobium Phosphorus Potassium Rubidium Scandium Selenium Silver

0-3 1,100 0.16 0.88 36 18 1,200 19,000 110 15 0.34 <3

3-6 910 .17 .69 33 16 960 19,000 110 15 .38 <3

9-12 1,100 1.0 1.1 41 20 1,200 20,000 120 16 .77 <3

12-15 1,100 1.2 1.2 42 18 1,200 21,000 120 15 1.1 <3

18-21 940 .58 1.7 36 18 1,100 21,000 120 14 .63 <3

21-24 970 .84 2.5 37 18 1,300 21,000 120 13 .62 <3

27-30 1,300 1.1 4.5 40 18 1,600 20,000 110 15 .62 <3

30-33 980 .61 2.2 26 15 1,000 16,000 91 15 .35 <3

33-35 960 .47 2.1 25 17 940 16,000 86 14 .24 <3

36-39 1,400 – 4.8 32 20 1,400 19,000 100 16 – <3

39-42 1,500 – 4.6 39 22 1,400 22,000 120 16 – <3

42-45 1,500 1.2 2.8 40 22 1,400 25,000 120 19 .75 <3

45-48 1,200 1.0 1.5 33 24 1,100 22,000 110 16 .69 <3

Depth

 interval 

(cm)

Sodium Strontium Tantalum Thallium Thorium Titanium Uranium Vanadium Ytterbium Yttrium Zinc

0-3 13,000 270 1.2 1.0 13 4,400 3.4 120 3.2 42 380

3-6 13,000 260 1.2 1.3 13 4,400 3.1 110 3.2 38 390

9-12 11,000 250 1.7 1.9 13 4,300 3.7 120 4.3 80 680

12-15 11,000 250 1.4 1.7 13 4,200 3.8 110 4.0 78 860

18-21 12,000 260 1.7 1.1 13 4,300 3.4 100 3.2 47 1,000

21-24 12,000 280 1.8 1.1 14 4,200 3.8 100 3.3 54 1,100

27-30 9,500 240 2.1 1.6 13 4,300 5.2 120 4.6 90 1,400

30-33 13,000 260 .65 1.2 11 4,500 3.2 110 3.6 50 730

33-35 14,000 280 1.2 1.0 10 4,600 3.0 120 3.2 44 530

36-39 11,000 230 – 1.2 13 4,800 4.3 130 – 56 1,100

39-42 10,000 230 – 1.7 14 4,500 4.6 120 – 75 1,600

42-45 9,400 210 1.2 1.5 14 4,800 4.1 130 4.0 60 1,400

45-48 11,000 200 1.8 1.1 13 4,900 3.0 110 3.7 48 1,100

Table 5. Vertical distribution of major and trace-element concentrations in sediment core subsections from Lake Roosevelt, Washington, September 

2002.—Continued

[Concentrations of trace elements are given in micrograms per kilogram unless otherwise noted. Abbreviations: cm, centimeter; pCi/g, picoCuries per gram;

<, less than; –, no data]

52 Vertical Distribution of Trace Elements and Metallurgical Slag in Sediments, Lake Roosevelt, Washington, 2002
CCR-643

Depth 

interval 

(cm)

Cesium-137 

(pCi/g) Aluminum Antimony Arsenic Barium Beryllium Bismuth Cadmium Calcium Carbonate (percent)

Organic 

carbon 

(percent)

0-3 0.19 74,000 3.2 13 1,100 2.3 0.59 2.3 11,000 0.05 1.2

3-6 – 72,000 4.0 11 1,100 2.2 .62 2.6 11,000 .07 1.2

9-12 – 69,000 4.6 15 1,000 2.3 .66 7.7 11,000 .06 1.3

15-18 .58 71,000 3.3 16 1,100 2.2 .68 7.9 12,000 .10 1.1

21-24 – 71,000 4.5 23 1,100 2.1 .86 10 20,000 .54 .98

27-30 .15 83,000 2.8 16 940 2.5 .85 2.8 20,000 .48 .64

33-36 .11 78,000 2.5 14 870 2.6 .82 2.4 19,000 .47 .61

36-39 .10 74,000 2.4 14 870 2.3 .80 2.4 20,000 .50 .56

39-42 – 67,000 2.7 16 870 2.1 .72 4.0 20,000 .49 .67

42-45 .61 70,000 3.7 18 1,000 2.1 .87 7.1 18,000 .38 .75

48-51 1.2 65,000 3.1 16 1,200 2.2 .57 8.0 18,000 .36 1.9

54-57 .98 78,000 7.4 24 1,200 2.1 .97 18 22,000 .68 1.1

Depth 

interval 

(cm)

Cerium Cesium Chromium Cobalt Copper Gallium Iron Lanthanum Lead Lithium Magnesium

0-3 120 6.5 83 16 58 17 41,000 74 94 40 14,000

3-6 110 6.6 80 15 76 17 39,000 74 130 39 14,000

9-12 120 6.3 110 15 76 17 39,000 120 310 37 14,000

15-18 130 6.3 100 15 60 17 38,000 120 280 39 14,000

21-24 120 5.9 85 14 50 17 36,000 96 400 36 16,000

27-30 120 9.3 86 16 41 20 43,000 67 96 46 15,000

33-36 120 9.2 75 16 39 19 41,000 64 78 46 15,000

36-39 130 8.8 72 15 38 18 39,000 73 79 43 15,000

39-42 130 7.1 67 13 37 17 35,000 83 190 37 14,000

42-45 120 5.5 74 13 44 16 34,000 89 380 33 13,000

48-51 100 4.9 68 12 42 15 31,000 88 380 30 13,000

54-57 110 6.6 93 15 73 18 41,000 122 920 41 17,000

Table 5. Vertical distribution of major and trace-element concentrations in sediment core subsections from Lake Roosevelt, Washington, September 

2002.—Continued

[Concentrations of trace elements are given in micrograms per kilogram unless otherwise noted. Abbreviations: cm, centimeter; pCi/g, picoCuries per gram;

<, less than; –, no data]

 Table 5 53
CCR-643—Continued

Depth 

interval 

(cm)

Manganese Mercury Molybdenum Nickel Niobium Phosphorus Potassium Rubidium Scandium Selenium Silver

0-3 1,500 0.21 1.4 48 20 1,200 22,000 120 14 0.58 <3

3-6 1,000 .28 1.4 44 19 1,100 22,000 120 13 .54 <3

9-12 1,200 1.3 1.6 47 20 1,400 22,000 110 13 1.0 <3

15-18 990 1.3 1.8 45 19 1,400 22,000 120 13 .84 <3

21-24 790 1.0 3.6 40 20 1,200 22,000 110 12 .70 <3

27-30 850 .14 1.6 41 18 990 26,000 140 16 .35 <3

33-36 840 .10 1.2 40 18 930 25,000 140 14 .31 <3

36-39 840 .10 1.2 38 21 960 24,000 140 14 .38 <3

39-42 740 .34 2.0 35 17 970 21,000 120 12 .40 <3

42-45 760 .86 3.3 37 18 1,200 22,000 110 12 .49 <3

48-51 780 .88 3.9 33 20 1,100 22,000 100 10 .58 <3

54-57 1,100 1.8 9.6 44 19 1,600 23,000 120 14 .76 <3

Depth 

interval 

(cm)

Sodium Strontium Tantalum Thallium Thorium Titanium Uranium Vanadium Ytterbium Yttrium Zinc

0-3 12,000 290 1.3 1.1 14 4,200 3.4 110 2.7 32 330

3-6 12,000 280 1.4 1.5 13 4,200 3.3 100 2.8 35 370

9-12 12,000 280 1.4 1.7 14 4,200 3.7 100 3.9 75 590

15-18 12,000 290 1.4 1.3 14 4,200 3.5 100 3.4 60 710

21-24 12,000 300 1.6 1.0 13 4,200 3.7 98 3.1 52 1,100

27-30 8,900 210 1.4 .88 14 4,300 3.3 110 3.0 38 410

33-36 9,200 210 1.3 .83 14 4,200 3.1 100 3.1 40 360

36-39 9,800 220 2.2 .79 14 4,200 3.2 100 2.9 32 340

39-42 12,000 260 1.7 .85 14 4,200 3.4 90 3.0 38 470

42-45 13,000 330 1.5 1.1 12 4,200 3.7 95 3.0 49 760

48-51 15,000 380 1.1 1.1 12 4,200 4.3 88 3.1 60 770

54-57 9,800 270 1.6 1.6 13 4,200 6.8 120 4.1 92 1,500

Table 5. Vertical distribution of major and trace-element concentrations in sediment core subsections from Lake Roosevelt, Washington, September 

2002.—Continued

[Concentrations of trace elements are given in micrograms per kilogram unless otherwise noted. Abbreviations: cm, centimeter; pCi/g, picoCuries per gram;

<, less than; –, no data]

54 Vertical Distribution of Trace Elements and Metallurgical Slag in Sediments, Lake Roosevelt, Washington, 2002
CCR-668

Depth 

interval 

(cm)

Cesium137 

(pCi/g)

Aluminum Antimony Arsenic Barium Beryllium Bismuth Cadmium Calcium Carbonate 

(percent)

Organic 

carbon 

(percent)

0-5 0.16 74,000 2.9 8.3 1,100 2.5 0.44 2.2 20,000 0.23 1.1

5-10 – 73,000 1.9 6.6 1,100 2.3 .30 1.7 22,000 .25 .86

10-15 – 73,000 4.4 8.8 1,100 2.6 .47 3.3 18,000 .25 1.8

20-25 – 73,000 6.4 11 1,200 2.5 .67 5.6 17,000 .12 1.4

30-35 .42 75,000 5.3 12 1,200 2.8 .82 11 17,000 .16 1.5

40-45 – 74,000 4.3 13 1,200 2.8 .75 11 23,000 .47 1.1

45-50 .46 68,000 5.7 17 1,400 2.5 .79 12 34,000 1.1 1.6

60-65 .23 59,000 4.1 12 1,600 2.0 .38 8.8 44,000 1.5 .72

65-70 .77 69,000 6.2 16 1,500 2.7 .81 16 33,000 1.1 1.3

80-85 .31 55,000 6.6 12 1,800 2.0 .89 11 57,000 2.1 1.2

90-95 .38 55,000 7.1 13 1,700 2.0 .88 12 54,000 2.0 1.2

100-105 .34 55,000 6.0 14 1,700 2.1 .92 11 54,000 2.0 1.3

105-110 .28 53,000 3.3 7.3 1,500 1.9 .70 6.8 52,000 1.9 .79

120-125 .54 71,000 4.8 13 1,500 2.5 .56 9.3 33,000 .89 .61

130-135 .76 70,000 9.4 20 1,500 2.4 .74 14 33,000 .96 .65

140-145 .43 44,000 9.9 12 820 1.6 .36 7.4 19,000 .67 .59

150-155 <.01 72,000 2.4 9.7 1,100 2.5 .51 4.6 25,000 .42 .38

155-160 .02 72,000 2.2 13 1,100 2.5 .47 5.1 25,000 .37 .38

160-164 .01 64,000 1.6 7.1 990 2.2 .43 4.2 24,000 .44 .32

Depth 

interval 

(cm)

Cerium Cesium Chromium Cobalt Copper Gallium Iron Lanthanum Lead Lithium Magnesium

0-5 92 4.2 69 14 54 17 38,000 53 86 30 16,000

5-10 92 3.4 76 12 38 16 34,000 52 67 26 15,000

10-15 84 4.5 76 13 92 17 39,000 50 150 31 16,000

20-25 93 4.6 100 15 100 17 41,000 71 290 32 16,000

30-35 98 5.0 110 15 89 18 42,000 75 410 34 17,000

40-45 94 4.8 96 13 62 18 40,000 67 340 33 20,000

45-50 81 4.4 84 13 72 16 42,000 57 480 32 27,000

60-65 76 2.5 57 8.9 52 13 35,000 49 310 20 26,000

65-70 88 4.7 80 13 70 16 42,000 64 580 33 27,000

80-85 69 2.8 67 9.5 72 13 36,000 51 620 23 32,000

90-95 68 2.9 66 9.7 75 13 37,000 50 660 23 30,000

100-105 69 2.8 65 9.8 73 13 38,000 49 560 23 32,000

105-110 61 2.3 56 8.6 52 13 31,000 40 330 20 26,000

120-125 90 4.0 87 13 53 17 38,000 63 460 30 23,000

130-135 92 4.3 72 14 63 16 38,000 64 800 31 24,000

140-145 54 2.4 39 7.6 33 10 22,000 36 440 18 13,000

150-155 98 3.6 78 12 43 16 34,000 60 360 27 17,000

155-160 97 3.7 77 14 42 17 36,000 60 320 28 16,000

160-164 89 3.2 71 13 37 15 33,000 51 250 24 15,000

Table 5. Vertical distribution of major and trace-element concentrations in sediment core subsections from Lake Roosevelt, Washington, September 

2002.—Continued

[Concentrations of trace elements are given in micrograms per kilogram unless otherwise noted. Abbreviations: cm, centimeter; pCi/g, picoCuries per gram;

<, less than; –, no data]

 Table 5 55
CCR-668—Continued

Depth 

interval 

(cm)

Manganese Mercury Molybdenum Nickel Niobium Phosphorus Potassium Rubidium Scandium Selenium Silver

0-5 790 0.25 1.0 35 27 – 25,000 96 12 0.86 <3

5-10 630 .17 1.0 32 31 1,200 25,000 91 11 .62 <3

10-15 740 .47 1.5 33 30 1,200 24,000 96 12 .86 <3

20-25 740 1.2 1.6 37 35 1,600 25,000 98 13 1.3 5

30-35 660 2.1 1.8 38 30 1,600 25,000 100 13 1.8 <3

40-45 610 1.7 2.0 36 28 1,600 25,000 100 13 1.4 3

45-50 620 1.1 4.4 35 29 1,400 23,000 92 12 1.4 <3

60-65 570 .61 4.1 25 23 1,300 21,000 75 8.6 .74 <3

65-70 680 1.4 4.3 34 31 1,600 23,000 94 12 1.4 4

80-85 600 1.9 8.1 28 23 1,400 20,000 72 8.7 1.2 3

90-95 620 2.1 8.2 29 26 1,400 19,000 73 8.8 1.2 3

100-105 610 1.8 8.4 30 24 1,400 19,000 72 8.7 .94 4

105-110 550 .75 6.3 24 23 1,200 19,000 73 7.4 .62 <3

120-125 700 1.1 4.6 36 29 1,600 25,000 95 12 .97 <3

130-135 740 1.6 8.5 36 29 1,600 24,000 94 12 1.1 3

140-145 430 1.2 4.0 20 17 910 16,000 59 6.9 .52 <3

150-155 650 1.0 2.4 32 29 1,300 26,000 93 11 .69 <3

155-160 670 .92 3.6 34 28 1,400 25,000 94 12 .70 <3

160-164 650 .77 1.9 31 26 1,200 23,000 83 11 .53 3

Depth

 interval 

(cm)

Sodium Strontium Tantalum Thallium Thorium Titanium Uranium Vanadium Ytterbium Yttrium Zinc

0-5 21,000 420 1.5 0.94 14 4,300 3.1 100 2.4 25 320

5-10 22,000 430 1.7 .84 12 4,100 2.3 96 2.2 23 210

10-15 20,000 380 1.6 1.1 12 4,200 3.5 100 2.7 29 530

20-25 19,000 390 2.0 1.8 13 3,800 3.7 110 3.8 50 550

30-35 20,000 400 1.7 1.4 14 4,500 3.9 110 3.5 51 900

40-45 19,000 390 1.6 1.0 14 4,400 3.5 100 3.2 42 1,000

45-50 19,000 380 1.6 1.1 12 4,000 4.0 100 3.1 36 1,200

60-65 21,000 440 1.3 .89 11 3,200 3.8 78 2.2 27 1,200

65-70 18,000 370 1.6 1.2 13 4,000 4.1 100 3.3 42 1,500

80-85 18,000 400 1.3 1.0 9.8 3,100 5.0 88 3.0 34 1,300

90-95 17,000 390 1.3 1.1 9.8 3,100 4.9 88 2.6 35 1,400

100-105 18,000 420 1.4 1.0 9.7 3,000 4.9 88 2.3 32 1,300

105-110 17,000 450 1.2 1.1 8.7 2,800 4.5 77 1.9 23 1,100

120-125 20,000 420 1.6 1.0 13 4,100 4.3 110 2.9 44 940

130-135 19,000 390 1.6 1.4 14 4,100 5.8 110 3.1 45 1,400

140-145 13,000 270 1.0 .66 7.8 2,400 2.9 64 1.8 22 700

150-155 22,000 440 1.6 .87 13 4,000 2.9 98 2.8 33 450

155-160 22,000 430 1.6 .85 13 4,400 2.8 100 3.3 35 500

160-164 20,000 400 1.4 .74 12 3,800 2.4 92 2.1 25 380

Table 5. Vertical distribution of major and trace-element concentrations in sediment core subsections from Lake Roosevelt, Washington, September 

2002.—Continued

[Concentrations of trace elements are given in micrograms per kilogram unless otherwise noted. Abbreviations: cm, centimeter; pCi/g, picoCuries per gram;

<, less than; –, no data]

56 Vertical Distribution of Trace Elements and Metallurgical Slag in Sediments, Lake Roosevelt, Washington, 2002
CCR-692

Depth 

interval 

(cm)

Cesium-137

(pCi/g) Aluminum Antimony Arsenic Barium Beryllium Bismuth Cadmium Calcium Carbonate (percent)

Organic 

carbon 

(percent)

0-2 0.46 63,000 5.7 9.2 1,200 2.3 0.80 3.7 21,000 0.42 2.8

2-4 – 61,000 5.5 10 1,200 2.1 .57 3.5 28,000 .80 2.4

6-8 .21 49,000 6.1 5.6 1,400 1.8 .19 3.6 51,000 2.0 0.6

10-12 .11 59,000 10 7.2 1,400 1.9 .24 2.9 34,000 .91 0.6

14-16 .22 60,000 9.9 7.6 1,300 2.0 .27 3.0 30,000 .74 0.8

18-20 .30 62,000 12 11 1,200 2.4 .64 4.8 24,000 .44 2.6

22-24 .32 61,000 18 15 1,200 2.4 .60 5.8 22,000 .29 4.0

26-28 .88 64,000 15 17 1,200 2.2 .70 8.4 20,000 .22 2.8

30-32 – 63,000 17 18 1,200 2.4 .86 11 18,000 .20 2.8

32-34 .46 64,000 10 14 1,200 2.3 .73 12 18,000 .21 2.6

34-36 – 63,000 8.0 12 1,200 2.2 .61 10 22,000 .38 2.1

36-38 .60 60,000 6.8 9.4 1,200 2.1 .43 7.6 25,000 .42 1.6

Depth 

interval 

(cm)

Cerium Cesium Chromium Cobalt Copper Gallium Iron Lanthanum Lead Lithium Magnesium

0-2 100 5.0 66 12 87 15 37,000 75 170 32 16,000

2-4 100 4.2 64 12 94 15 35,000 70 190 30 18,000

6-8 84 1.8 44 7.2 82 12 25,000 53 210 17 26,000

10-12 100 1.9 56 8.8 130 14 29,000 68 150 18 16,000

14-16 88 2.8 58 9.9 140 14 30,000 66 170 21 15,000

18-20 120 4.4 74 14 190 15 39,000 94 260 31 16,000

22-24 110 4.5 79 15 240 15 40,000 95 290 32 14,000

26-28 110 4.7 92 13 250 16 39,000 130 420 34 13,000

30-32 110 5.4 110 12 220 16 40,000 160 610 36 14,000

32-34 130 4.9 99 12 160 16 39,000 150 540 33 14,000

34-36 110 4.2 81 11 140 15 38,000 110 440 30 15,000

36-38 100 3.3 66 9.9 140 14 42,000 92 380 24 14,000

Table 5. Vertical distribution of major and trace-element concentrations in sediment core subsections from Lake Roosevelt, Washington, September 

2002.—Continued

[Concentrations of trace elements are given in micrograms per kilogram unless otherwise noted. Abbreviations: cm, centimeter; pCi/g, picoCuries per gram;

<, less than; –, no data]

 Table 5 57
CR-692—Continued

Depth 

interval 

(cm)

Manganese Mercury Molybdenum Nickel Niobium Phosphorus Potassium Rubidium Scandium Selenium Silver

0-2 770 0.55 2.2 35 21 1,400 19,000 97 11 0.86 <3

2-4 700 .27 3.8 32 19 1,300 19,000 91 9.9 .93 <3

6-8 530 .19 7.6 20 16 1,200 17,000 72 6.3 .54 <3

10-12 580 .18 3.6 21 18 1,400 20,000 81 7.5 .54 <3

14-16 600 .24 3.3 23 17 1,200 20,000 86 7.8 .69 <3

18-20 770 .43 3.0 35 23 1,400 19,000 94 10 1.3 4

22-24 820 .66 2.7 34 22 1,500 18,000 92 11 1.4 5

26-28 720 1.4 3.0 36 22 1,500 20,000 94 11 1.6 4

30-32 730 2.3 2.6 38 21 1,700 19,000 100 11 2.1 8

32-34 700 2.0 2.4 38 21 1,600 20,000 98 11 2.2 <3

34-36 670 1.9 3.4 34 20 1,500 20,000 95 9.9 1.8 <3

36-38 780 1.2 4.3 26 18 1,400 20,000 88 8.5 1.3 <3

Depth 

interval 

(cm)

Sodium Strontium Tantalum Thallium Thorium Titanium Uranium Vanadium Ytterbium Yttrium Zinc

0-2 17,000 440 1.4 0.89 12 4,100 4.7 87 2.8 33 630

2-4 17,000 470 1.2 .92 12 4,100 5.0 83 2.4 30 730

6-8 18,000 520 1.5 .75 9.8 4,000 4.6 58 1.7 20 970

10-12 20,000 600 1.2 .95 9.9 4,000 3.5 65 2.1 27 960

14-16 20,000 590 1.0 1.1 10 4,000 3.8 63 2.0 32 980

18-20 17,000 480 1.5 1.5 13 4,100 4.9 87 2.9 41 1,000

22-24 16,000 460 1.3 1.8 12 4,100 5.9 88 3.0 48 1,200

26-28 15,000 440 1.5 1.8 12 4,200 5.2 93 4.0 78 1,200

30-32 15,000 420 1.4 1.5 13 4,100 5.5 100 4.4 100 1,300

32-34 16,000 450 1.3 1.5 13 4,100 5.1 89 3.8 78 1,300

34-36 18,000 500 1.3 1.2 13 4,100 4.9 84 3.0 56 1,400

36-38 19,000 520 1.2 .86 27 4,100 6.8 80 2.6 43 2,200

Table 5. Vertical distribution of major and trace-element concentrations in sediment cores subsections from Lake Roosevelt, Washington, September 

2002.—Continued

[Concentrations of trace elements are given in micrograms per kilogram unless otherwise noted. Abbreviations: cm, centimeter; pCi/g, picoCuries per gram;

<, less than; –, no data]

58 Vertical Distribution of Trace Elements and Metallurgical Slag in Sediments, Lake Roosevelt, Washington, 2002
CCR-705

Depth 

interval 

(cm)

Cesium-137

(pCi/g) Aluminum Antimony Arsenic Barium Beryllium Bismuth Cadmium Calcium Carbonate (percent)

Organic 

carbon 

(percent)

0-2 – 81,000 5.6 9.8 1,200 2.6 0.72 5.2 18,000 0.13 1.7

2-4 0.55 81,000 6.7 11 1,200 2.4 .70 6.5 18,000 .14 1.5

6-8 .72 81,000 6.1 13 1,400 2.5 .73 11 23,000 .37 1.2

14-16 .92 77,000 9.6 16 1,700 2.6 .80 15 33,000 .96 1.1

18-20 1.2 72,000 11 20 1,800 2.3 .82 18 40,000 1.4 .91

22-24 .04 84,000 5.2 11 1,400 2.6 .54 7.3 36,000 .87 .72

26-28 .03 75,000 1.9 5.4 1,100 2.2 .30 2.8 31,000 .70 .68

30-32 <.01 40,000 .98 2.1 580 1.3 .19 1.4 16,000 .68 .63

34-36 .16 59,000 1.1 3.6 870 1.9 .19 1.5 23,000 .54 .69

36-38 .19 77,000 1.7 4.4 1,100 2.3 .26 1.6 26,000 .40 .72

40-42 <.01 76,000 6.1 18 1,100 2.6 1.3 16 23,000 .47 2.3

42-44 .02 54,000 3.5 15 760 1.8 .88 10 14,000 .20 4.9

44-46 <.01 55,000 1.5 6.7 750 1.7 .30 2.7 13,000 .02 6.8

46-49 – 57,000 1.7 6.5 780 1.7 .41 4.2 15,000 .08 6.3

RSS-743 – 27,000 160 28 2,800 1.1 <0.005 0.004 99,000 – –

Depth 

interval 

(cm)

Cerium Cesium Chromium Cobalt Copper Gallium Iron Lanthanum Lead Lithium Magnesium

0-2 93 5.1 94.1 14 91 18 44,000 60 260 32 16,000

2-4 96 4.9 106 14 100 18 44,000 68 350 33 16,000

6-8 93 4.6 108 14 79 18 43,000 69 500 31 18,000

14-16 90 4.6 100 13 68 17 43,000 67 680 32 25,000

18-20 86 4.2 92.6 12 67 16 42,000 64 850 30 27,000

22-24 93 4.4 91.5 14 59 19 43,000 57 450 35 21000

26-28 90 3.8 79.6 13 37 18 37,000 51 200 31 17,000

30-32 48 2.0 41.3 6.3 18 9.2 19,000 29 85 17 9,200

34-36 72 2.5 54.7 8.2 29 13 25,000 42 86 21 12,000

36-38 77 3.2 65.3 11 26 16 30,000 45 90 25 13,000

40-42 86 4.8 89.7 12 74 18 34,000 65 850 34 19,800

42-44 75 4.5 56.2 9.8 52 12 22,000 61 500 28 11,000

44-46 47 3.6 49.1 6.5 32 12 20,000 30 61 22 7,500

46-49 56 3.7 53.9 6.7 37 13 22,000 35 130 22 8,700

RSS-743 47 0.78 250 88 3,600 35 320,000 25 400 18 8,300

Table 5. Vertical distribution of major and trace-element concentrations in sediment core subsections from Lake Roosevelt, Washington, September 

2002.—Continued

[Concentrations of trace elements are given in micrograms per kilogram unless otherwise noted. Abbreviations: cm, centimeter; pCi/g, picoCuries per gram;

<, less than; –, no data]

 Table 5 59
CCR-705—Continued

Depth 

interval 

(cm)

Manganese Mercury Molybdenum Nickel Niobium Phosphorus Potassium Rubidium Scandium Selenium Silver

0-2 1,000 0.93 1.6 37 36.1 1,600 27,000 110 13 1.1 5

2-4 860 1.2 1.6 37 35.9 1,700 27,000 100 13 1.2 4

6-8 700 2.2 2.8 37 34.9 1,800 28,000 100 13 1.5 <3

14-16 720 2.0 7.3 36 33.2 2,100 26,000 100 13 1.4 7

18-20 750 1.8 9.1 36 31.4 2,100 25,000 95 12 1.4 3

22-24 750 .88 4.0 39 36.7 1,400 29,000 110 14 .54 <3

26-28 690 .47 1.7 34 33.7 1,200 27,000 99 12 .55 <3

30-32 380 .46 .71 18 16.0 650 14,000 50 6.3 .38 <3

34-36 540 .29 .86 22 24.8 970 21,000 72 8.8 .34 <3

36-38 570 .23 1.3 28 29.0 1,100 28,000 90 11 .41 <3

40-42 530 2.8 7.0 35 32.7 1,600 26,000 110 13 1.4 <3

42-44 380 1.5 5.9 28 19.81 1,200 17,000 91 9.0 1.9 <3

44-46 310 .14 2.2 19 19.2 1,100 18,000 79 8.6 2.4 <3

46-49 350 .38 2.4 21 21.1 1,200 18,000 82 9.1 2.2 <3

RSS-743 5,400 – 54 26 5.0 570 4,800 20 6.2 – 9

Depth 

interval 

(cm)

Sodium Strontium Tantalum Thallium Thorium Titanium Uranium Vanadium Ytterbium Yttrium Zinc

0-2 18,000 430 1.9 1.3 14 4,200 3.6 110 2.9 35 560

2-4 19,000 440 1.8 1.4 14 4,100 3.7 110 3.2 46 640

6-8 19,000 450 2.6 1.4 13 4,200 3.8 110 3.1 47 960

14-16 18,000 420 2.0 1.4 13 4,100 5.5 120 3.2 48 1,400

18-20 16,000 400 2.0 1.5 12 3,800 6.5 110 3.2 48 1,600

22-24 20,000 500 2.1 1.0 14 4,400 3.4 120 2.6 32 740

26-28 19,000 480 1.9 .71 13 4,100 2.5 98 2.2 24 300

30-32 11,000 260 1.0 .38 7.4 2,100 1.4 51 1.2 13 150

34-36 18,000 420 1.3 .50 10 3,100 1.9 69 1.7 18 160

36-38 22,000 530 1.5 .74 11 3,800 2.3 90 2.2 22 170

40-42 17,000 400 1.8 1.3 13 4,000 6.0 110 3.2 49 1,200

42-44 12,000 310 1.3 .81 11 4,000 9.5 72 2.6 36 770

44-46 12,000 310 1.1 .62 8.6 2,500 13 62 1.9 19 180

46-49 12,000 310 1.2 .69 9.4 2,700 14 67 2.3 21 300

RSS-743 2,900 430 – 0.02 7.3 3,600 6.2 50 – 23 25,000

Table 5. Vertical distribution of major and trace-element concentrations in sediment core subsections from Lake Roosevelt, Washington, September 

2002.—Continued

[Concentrations of trace elements are given in micrograms per kilogram unless otherwise noted. Abbreviations: cm, centimeter; pCi/g, picoCuries per gram;

<, less than; –, no data]

60 Vertical Distribution of Trace Elements and Metallurgical Slag in Sediments, Lake Roosevelt, Washington, 2002
CSA-8

Depth 

interval 

(cm)

Cesium-137

(pCi/g) Aluminum Antimony Arsenic Barium Beryllium Bismuth Cadmium Calcium Carbonate (percent)

Organic 

carbon 

(percent)

0-3 0.17 84,000 2.6 20 770 2.8 1.1 7.0 9,800 0.06 2.4 

3-6 – 78,000 1.9 18 730 2.6 1.1 5.7 12,000 .11 1.9

6-9 – 85,000 2.6 20 760 2.7 1.1 7.8 9,200 .04 2.4

9-12 .32 76,000 8.0 24 790 2.4 .81 10 8,900 .04 2.4

15-18 .25 81,000 2.4 20 710 2.7 1.2 14 11,000 .05 1.9

21-24 .29 74,000 2.3 19 700 2.6 .94 13 13,000 .07 1.6

27-30 .36 74,000 2.8 17 700 2.5 .95 21 12,000 .05 1.8

33-36 .33 74,000 3.0 13 700 2.5 1.2 18 13,000 .05 1.7

39-42 .2 70,000 2.0 11 660 2.2 .96 8.0 15,000 .09 1.3

45-48 .24 70,000 2.1 13 660 2.2 1.9 8.0 15,000 .09 1.4

51-54 .24 71,000 2.1 12 680 2.2 1.2 7.6 15,000 .09 1.5

57-60 .33 72,000 2.4 13 690 2.5 1.5 14 13,000 .06 1.7

63-66 1.1 83,000 5.7 34 740 2.7 1.3 14 10,200 .03 2.2

69-72 .36 73,000 3.2 20 740 2.4 2.0 7.0 11,000 .03 1.2

75-78 .34 72,000 2.7 16 710 2.3 2.2 18 12,000 .06 1.6

78-81 – 74,000 2.2 10 650 2.1 .84 9.5 15,000 .07 1.5

81-84 .31 72,000 2.2 12 690 2.6 1.8 8.8 15,000 .07 1.5

86-90 – 78,000 2.8 13 700 2.3 1.4 10 14,000 .06 1.7

Depth 

interval 

(cm)

Cerium Cesium Chromium Cobalt Copper Gallium Iron Lanthanum Lead Lithium Magnesium

0-3 82 9.2 64 17 44 20 50,000 41 140 45 13,000

3-6 77 7.8 55 15 40 19 43,000 40 88 39 13,000

6-9 77 8.8 63 16 48 21 50,000 41 140 45 12,000

9-12 69 8.0 64 16 53 20 45,000 36 130 42 12,000

15-18 76 7.5 58 16 46 20 42,000 40 110 40 12,000

21-24 76 6.6 49 13 34 18 37,000 40 92 34 12,000

27-30 75 6.7 51 14 38 18 39,000 40 110 35 12,000

33-36 80 6.7 51 14 34 18 38,000 42 100 34 12,000

39-42 76 5.8 42 12 29 16 34,000 40 72 30 11,000

45-48 82 6.0 46 12 31 16 35,000 43 74 30 11,000

51-54 82 6.2 35 12 31 16 35,000 43 69 32 11,000

57-60 74 6.4 48 13 36 17 36,000 39 86 34 11,000

63-66 80 7.7 60 18 51 20 46,000 43 140 41 11,000

69-72 80 7.0 50 13 38 17 37,000 43 210 34 11,000

75-78 81 6.5 51 14 36 18 38,000 43 100 34 12,000

78-81 75 6.1 54 13 31 17 36,000 38 87 32 9,700

81-84 78 6.4 48 12 32 17 36,000 41 79 33 12,000

86-90 73 6.6 49 13 36 18 38,000 38 83 33 12,000

Table 5. Vertical distribution of major and trace-element concentrations in sediment core subsections from Lake Roosevelt, Washington, September 

2002.—Continued

[Concentrations of trace elements are given in micrograms per kilogram unless otherwise noted. Abbreviations: cm, centimeter; pCi/g, picoCuries per gram;

<, less than; –, no data]

 Table 5 61
CSA-8—Continued

Depth 

interval 

(cm)

Manganese Mercury Molybdenum Nickel Niobium Phosphorus Potassium Rubidium Scandium Selenium Silver

0-3 1,600 0.10 0.75 28 23 1,300 22,000 120 17 0.65 <3

3-6 930 .08 .65 25 18 1,000 22,000 110 16 .39 <3

6-9 1,200 .11 .80 30 23 1,400 22,000 120 18 .82 <3

9-12 940 .25 1.2 29 22 1,300 20,000 110 16 .69 <3

15-18 860 .15 .86 26 21 1,100 21,000 110 15 .74 <3

21-24 750 .15 .65 21 20 990 21,000 100 14 .46 <3

27-30 840 .19 .66 23 19 1,200 21,000 100 14 .68 <3

33-36 790 .18 .56 22 20 1,200 21,000 100 14 .38 <3

39-42 670 .09 .55 18 19 980 21,000 94 13 .40 <3

45-48 680 .09 .61 19 18 1,000 21,000 94 13 .40 <3

51-54 640 .09 .71 19 19 970 21,000 96 13 .64 <3

57-60 720 .14 .55 21 16 1,000 20,000 99 13 .49 <3

63-66 980 .30 .86 28 20 1,300 21,000 120 17 .52 <3

69-72 680 .13 .65 20 20 890 24,000 120 13 .42 <3

75-78 820 .19 .64 22 18 1,200 22,000 100 14 .42 <3

78-81 730 .10 .79 21 15 1,100 22,000 100 14 .46 <3

81-84 690 .10 .65 20 15 1,000 21,000 99 13 .32 <3

86-90 730 .13 .82 22 22 1,000 22,000 120 17 .65 <3

Depth 

interval 

(cm)

Sodium Strontium Tantalum Thallium Thorium Titanium Uranium Vanadium Ytterbium Yttrium Zinc

0-3 8,700 140 1.7 0.88 14 5,400 6.4 100 3.8 32 1,200

3-6 11,000 170 1.1 .76 13 5,300 5.7 98 3.4 29 950

6-9 8,600 140 1.8 .89 13 5,400 6.0 110 3.6 32 1,200

9-12 8,300 130 1.8 .81 12 4,900 6.4 97 3.1 28 1,600

15-18 12,000 170 1.5 1.0 12 5,200 5.6 95 3.4 31 1,500

21-24 15,000 210 1.3 .84 11 5,100 4.4 86 3.6 28 1,200

27-30 14,000 200 .96 .92 11 5,100 4.1 89 3.1 28 1,600

33-36 15,000 210 1.3 .83 12 5,300 4.0 88 3.2 28 1,400

39-42 16,000 240 1.5 .67 11 5,300 3.6 85 3.1 26 930

45-48 16,000 230 1.2 .64 12 5,200 3.5 86 3.0 26 960

51-54 15,000 230 1.4 .66 12 5,200 3.4 84 3.0 26 890

57-60 14,000 210 1.0 .73 11 5,100 3.6 85 3.1 26 1,300

63-66 9,700 160 1.6 1.0 13 5,500 4.8 98 3.7 34 1,500

69-72 12,000 210 1.4 .76 12 4,600 3.3 85 2.9 26 980

75-78 14,000 200 1.0 .86 12 5,000 4.1 88 3.2 27 1,400

78-81 12,000 220 .61 .66 11 4,300 3.2 89 2.6 25 1,100

81-84 16,000 230 1.0 .73 12 5,200 3.6 86 3.2 27 1,000

86-90 15,000 220 1.5 .73 11 5,200 3.3 88 3.0 27 1,100

Table 5. Vertical distribution of major and trace-element concentrations in sediment core subsections from Lake Roosevelt, Washington, September 

2002.—Continued

[Concentrations of trace elements are given in micrograms per kilogram unless otherwise noted. Abbreviations: cm, centimeter; pCi/g, picoCuries per gram;

<, less than; –, no data]

62 Vertical Distribution of Trace Elements and Metallurgical Slag in Sediments, Lake Roosevelt, Washington, 2002
Table 6 63

Sample designation Aluminum Antimony Arsenic Barium Beryllium Bismuth Cadmium Calcium

Standard Reference Material (SRM)—Italicized number is percentage recovery of SRM

PACS-2 66,200 11.3 26.2 – 1.0 – 2.11 119,600

Sample 1 71,000 107 12.4 110 25 95 1,000 – 1.1 110 0.37 – 2.3 109 20,000 102

Sample 2 71,000 107 12.4 110 28 107 1,000 – 1.1 110 .26 – 2.4 114 22,000 112

Sample 3 60,000 91 11.1 98 25 95 890 – .92 92 .38 – 2.2 104 18,000 92

BR-2704 61,100 3.79 23.4 414 – – 3.45 26,000

Sample 4 64,000 105 3.9 103 22 99 420 101 1.9 – .50 – 3.7 107 27,000 104

Sample 5 56,000 92 3.6 95 21 90 390 94 1.6 – .64 – 3.3 96 23,000 88

Sample 6 66,000 108 4.6 121 20 85 450 109 2.0 – .63 – 3.5 101 26,000 100

Environmental Duplicate Samples (EDS)—Italicized number is relative percentage difference of EDS

CCR624:3-6 77,000 0.0 3.1 9.8 10 9.5 820 0.0 2.3 9.1 0.54 7.1 2.1 4.9 12,800 1.6

CCR624:3-6DUP 77,000 2.9 11 820 2.1 .58 2.0 13,000

CCR-643:3-6 72,000 1.4 4.0 2.5 11 8.1 1,100 .0 2.2 .0 .62 6.7 2.6 .0 11,000 .0

CCR-643:3-6DUP 73,000 3.9 12 1,100 2.2 .58 2.6 11,000

CCR668:10-15 73,000 2.7 4.4 .0 8.8 7.6 1,100 8.7 2.6 7.4 .47 19.2 3.3 8.7 18,000 5.4

CCR668:10-15DUP 75,000 4.4 9.5 1,200 2.8 .57 3.6 19,000

CCR692:2-4 61,000 1.6 5.5 5.6 10 2.0 1,200 .0 2.1 21 .57 11.1 3.5 2.9 28,000 7.4

CCR692:2-4DUP 62,000 5.2 9.8 1,200 2.6 .51 3.4 26,000

CCR705:14-16 77,000 .0 9.6 24.6 16 .0 1,700 .0 2.6 .0 .80 4.9 15 .0 33,000 3.1

CCR705:14-16DUP 77,000 7.5 16 1,700 2.6 .84 15 32,000

CSA:3-6 80,000 2.5 2.1 10 17 5.7 750 2.7 2.7 3.8 .94 15.7 5.7 .0 12,000 .0

CSA:3-6DUP 78,000 1.9 18 730 2.6 1.1 5.7 12,000

Sample designation

Organic 

carbon 

(percent)

Total carbon 

(percent) Cerium Cesium Chromium Cobalt Copper Gallium

Standard Reference Material (SRM)—Italicized number is percentage recovery of SRM

PACS-2 – 13.3 – – 90.7 11.5 310 –

Sample 1 3.1 – 3.2 97 34 – 2.2 – 90 99 11.7 102 300 97 14 –

Sample 2 3.1 – 3.2 97 31 – 2.2 – 110 121 12.6 110 330 106 14 –

Sample 3 3.0 – 3.1 94 23 – 2.6 – 82 90 10.8 94 280 90 13 –

BR-2704 – 3.35 172 16 135 14.0 98.6 115

Sample 4 2.5 – 3.4 101 57 79 5.4 90 160 119 14.2 101 98 99 15 100

Sample 5 2.4 – 3.3 99 76 106 5.9 98 120 89 12.6 90 89 90 14 93

Sample 6 2.5 – 3.4 101 61 85 5.4 90 140 104 13.2 94 94 95 14 93

Environmental Duplicate Samples (EDS)—Italicized number is relative percentage difference of EDS

CCR624:3-6 1.4 0.0 1.4 0.0 110 0.0 6.4 1.6 62 1.6 15.8 0.6 70 19 19 5.4

CCR624:3-6DUP 1.4 1.4 110 6.3 61 15.7 58 18

CCR-643:3-6 1.2 .0 1.2 8.0 110 16.7 6.6 .0 80 2.5 14.7 .7 76 1.3 17 5.7

CCR-643:3-6DUP 1.2 1.3 130 6.6 82 14.8 75 18

CCR668:10-15 1.8 11.8 2.0 5.1 84 2.4 4.5 6.4 76 .0 13.4 4.4 92 4.3 17 5.7

CCR668:10-15DUP 1.6 1.9 86 4.8 76 14.0 96 18

CCR692:2-4 2.4 .0 3.2 3.2 100 9.5 4.2 2.4 64 .0 11.6 1.7 94 5.5 15 .0

CCR692:2-4DUP 2.4 3.1 110 4.1 64 11.4 90 15

CCR705:14-16 1.1 .0 2.0 .0 90 2.2 4.6 .0 100 .0 12.6 .8 68 1.5 17 .0

CCR705:14-16DUP 1.1 2.0 92 4.6 100 12.7 67 17

CSA8:3-6 1.9 .0 2.0 .0 79 2.6 8.1 3.8 56 1.8 15.4 2.0 64 46 19 .0

CSA8:3-6DUP 1.9 2.0 77 7.8 55 15.1 40 19

Table 6. Analytical results for standard reference material and environmental duplicate samples for quality assurance.

[Concentrations are in micrograms per kilogram unless otherwise noted. Sample designation: PACS-2: Standard reference material (SRM) from the National 

Research Council of Canada. SRMs are reported. BR-2704: SRM from the U.S. National Institute of Standards and Testing, Special Publication 260 (1990–91). 

<, less than; –, no data]
Table 6. Analytical results for standard reference material and environmental duplicate samples for quality assurance.—Continued

[Concentrations are in micrograms per kilogram unless otherwise noted. Sample designation: PACS-2: Standard reference material (SRM) from the National 

Research Council of Canada. SRMs are reported. BR-2704: SRM from the U.S. National Institute of Standards and Testing, Special Publication 260 (1990–91). 

<, less than; –, no data]

Sample designation Iron Lanthanum Lead Lithium Magnesium Manganese Mercury

Standard Reference Material (SRM)—Italicized number is percentage recovery of SRM

PACS-2 40,900 – 183 32.2 14,700 440 3.04

Sample 1 44,000 108 18 – 160 87 30 93 16,000 109 440 100 2.8 92

Sample 2 45,000 110 16 – 180 98 32 99 14,000 95 470 107 2.9 95

Sample 3 38,000 93 2.9 – 180 98 32 99 14,000 95 440 100 2.8 92

BR-2704 41,100 129 161 150 12,000 555 1.44

Sample 4 43,000 105 30 103 150 93 45 90 12,000 100 600 108 1.4 97

Sample 5 37,000 90 33 114 160 99 44 88 11,000 92 580 104 1.5 104

Sample 6 43,000 105 31 107 200 124 42 84 13,000 108 580 104 1.4 97

Environmental Duplicate Samples (EDS)—Italicized number is relative percentage difference of EDS

CCR624:3-6 42,000 0.0 65 1.5 110 9.5 39 2.6 12,000 8.7 910 1.1 0.17 6.1

CCR624:3-6DUP 42,000 66 100 38 11,000 900 .16

CCR-643:3-6 39,000 .0 74 13.8 130 7.4 39 2.5 14,000 .0 1,000 .0 .28 6.9

CCR-643:3-6DUP 39,000 85 140 40 14,000 1,000 .30

CCR668:10-15 39,000 2.5 50 7.7 150 6.4 31 9.2 16,000 .1 740 2.7 .47 26

CCR668:10-15DUP 40,000 54 160 34 17,000 760 .36

CCR692:2-4 35,000 .0 70 5.6 190 11 30 3.4 18,000 12 700 1.4 .27 3.8

CCR692:2-4DUP 35,000 74 170 29 16,000 690 .26

CCR705:14-16 43,000 .0 67 2.9 680 .0 32 .0 25,000 .0 720 .0 2.0 .0

CCR705:14-16DUP 43,000 69 680 32 25,000 720 2.0

CSA:3-6 44,000 2.3 41 2.5 88 .0 40 .2.5 14,000 7.4 960 3.2 .08 .0

CSA:3-6DUP 43,000 40 88 39 13,000 930 .08

Sample designation Molybdenum Nickel Niobium Phosphorus Potassium Rubidium Scandium

Standard Reference Material (SRM)—Italicized number is percentage recovery of SRM

PACS-2 5.43 39.5 – 960 12,400 – –

Sample 1 6.1 112 37 94 13 – 1,000 104 14,000 113 42 – 15 –

Sample 2 5.9 109 42 106 11 – 1,200 125 14,000 113 43 – 16 –

Sample 3 6.4 118 40 101 8.5 – 920 96 11,000 89 44 – 13 –

BR-2704 – 44.1 – 998 20,000 1100 112

Sample 4 4.6 – 43 98 15 – 1,100 110 21,000 105 98 98 13 108

Sample 5 4.7 – 45 102 9.3 – 920 92 18,000 90 100 100 11 92

Sample 6 4.6 – 41 93 15 – 1,000 102 22,000 110 96 96 12 100

Environmental Duplicate Samples (EDS)—Italicized number is relative percentage difference of EDS

CCR624:3-6 0.69 35 33 0.0 16 6.1 960 4.3 19,000 0.0 108 0.9 15 0.0

CCR624:3-6DUP 1.0 33 17 920 19,000 107 15

CCR-643:3-6 1.4 .0 44 .0 19 .0 1,100 .0 22,000 .0 117 .9 13 .0

CCR-643:3-6DUP 1.4 44 19 1,100 22,000 118 13

CCR668:10-15 1.5 12 33 3.0 30 18 1,200 8.0 24,000 4.1 96.0 4.1 12 8

CCR668:10-15DUP 1.7 34 25 1,300 25,000 100 13

CCR692:2-4 3.8 2.7 32 .0 19 5.1 1,300 .0 19,000 .3 91.2 .2 9.9 2.0

CCR692:2-4DUP 3.7 32 20 1,200 19,000 91.0 9.7

CCR705:14-16 7.3 15 36 .0 33 3.0 2,100 .0 26,000 .0 101 .0 13 .0

CCR705:14-16DUP 6.3 36 34 2,100 26,000 101 13

CSA:3-6 .86 28 25 .0 23 24 1,000 .0 23,000 4.4 113 1.8 16 .0

CSA:3-6DUP .65 25 18 1,000 22,000 111 16

64 Vertical Distribution of Trace Elements and Metallurgical Slag in Sediments, Lake Roosevelt, Washington, 2002
Sample designation Selenium Silver Sodium Strontium Tantalum Thallium Thorium

Standard Reference Material (SRM)—Italicized number is percentage recovery of SRM

PACS-2 0.92 1.22 34,500 276 – – 10.6 –

Sample 1 1.0 109 <3 – 38,000 110 290 105 0.92 – .70 117 4.1 –

Sample 2 1.2 130 <3 – 33,000 96 290 105 .39 – .65 108 4.0 –

Sample 3 .81 88 <3 – 31,000 90 290 105 .25 .60 100 6.1 –

BR-2704 11.1 – 5,470 1130 – – 1.2 9.2

Sample 4 1.2 109 <3 – 5,500 101 130 100 .74 – 1.1 92 8.6 93

Sample 5 1.1 100 <3 – 5,400 99 130 100 <.20 – 1.1 92 9.6 104

Sample 6 1.1 100 <3 – 6,400 117 140 108 1.1 1.2 100 8.6 93

Environmental Duplicate Samples (EDS)—Italicized number is relative percentage difference of EDS

CCR624:3-6 0.38 14 <3 0.0 13,000 8.0 260 0.0 1.2 15 1.3 8.0 13 0.0

CCR624:3-6DUP .33 <3 12,000 260 1.4 1.2 13

CCR-643:3-6 .54 18 <3 .0 12,000 .0 280 3.5 1.4 .0 1.5 .0 13 7.4

CCR-643:3-6DUP .65 <3 12,000 290 1.4 1.5 14

CCR668:10-15 .86 3.6 <3 .0 20,000 .0 380 2.6 1.6 6.4 1.1 .0 12 8

CCR668:10-15DUP .83 <3 20,000 390 1.5 1.1 13

CCR692:2-4 .93 18 <3 .0 17,000 6.1 470 .0 1.2 8 .92 6.7 12 .0

CCR692:2-4DUP .78 <3 16,000 470 1.3 .86 12

CCR705:14-16 1.4 15 7 55 18,000 .0 420 .0 2.0 18 1.4 6.9 13 .0

CCR705:14-16DUP 1.2 4 18,000 420 2.4 1.5 13

CSA:3-6 .55 34 <3 .0 12,000 8.0 170 .0 1.6 37 .80 5.1 12 8

CSA:3-6DUP .39 <3 11,000 170 1.1 .76 13

Field No. Titanium Uranium Vanadium Ytterbium Yttrium Zinc

Standard Reference Material (SRM)—Italicized number is percentage recovery of SRM

PACS-2 4,430 13 133 – – 364

Sample 1 5,100 115 2.2 73 140 105 2.0 – 18 – 352 97

Sample 2 4,400 99 2.2 73 150 113 1.9 – 18 – 411 113

Sample 3 4,300 97 2.2 73 120 90 1.9 – 20 – 343 94

BR-2704 4,570 3.13 95 – – 438

Sample 4 3,600 79 2.8 89 100 105 2.8 – 24 – 465 106

Sample 5 4,100 90 2.8 89 86 91 3.1 – 31 – 404 92

Sample 6 3,800 83 2.7 86 93 98 3.2 – 26 – 405 92

Environmental Duplicate Samples (EDS)—Italicized number is relative percentage difference of EDS

CCR624:3-6 4,400 0.0 3.1 0.0 110 0.0 3.2 3.2 38 0.0 390 8

CCR624:3-6DUP 4,400 3.1 110 3.1 38 360

CCR-643:3-6 4,200 .0 3.3 5.9 100 .0 2.8 13 35 .0 370 2.7

CCR-643:3-6DUP 4,200 3.5 100 3.2 35 380

CCR668:10-15 3,800 10 3.2 9.0 97 3.0 2.5 7.7 28 3.5 480 9.9

CCR668:10-15DUP 4,200 3.5 100 2.7 29 530

CCR692:2-4 4,100 .0 5.0 6.2 83 1.2 2.4 4.1 30 15 730 4.2

CCR692:2-4DUP 4,100 4.7 82 2.5 35 700

CCR705:14-16 4,100 2.5 5.5 .0 120 8.7 3.2 .0 48 .0 1,400 .0

CCR705:14-16DUP 4,000 5.5 110 3.2 48 1,400

CSA:3-6 5,200 1.9 5.6 1.8 98 .0 3.6 5.7 31 5.7 920 3.2

CSA:3-6DUP 5,300 5.7 98 3.4 29 950

1Value is uncertified and is included for reference only.

Table 6. Analytical results for standard reference material and environmental duplicate samples for quality assurance.—Continued

[Concentrations are in micrograms per kilogram unless otherwise noted. Sample designation: PACS-2: Standard reference material (SRM) from the National 

Research Council of Canada. SRMs are reported. BR-2704: SRM from the U.S. National Institute of Standards and Testing, Special Publication 260 (1990–91). 

<, less than; –, no data]

Table 6 65
Table 7. Vertical distribution of concentrations of selected trace elements and major ions in pore water, bulk sediment, and residual sediment from shallow 

cores from sites CCR-668, CCR-692, and CCR-705, Lake Roosevelt, Washington, July 2003.

[Bulk and Residual Sediment Analysis: Replicate analysis of bulk sediment. Residual Sediment: Concentrations of residual sediment following 30 minute 

leach with 0.25 Molar hydroxylamine hydrochloride. Residual Percent: Residual as percentage of unleached bulk-sediment concentration. Abbreviations: cm, 

centimeter; mg/L, milligram per liter; <, less than; –, no data]

Sediment core 

sampling site

Depth 

interval 

(cm)

Aluminum Antimony Arsenic Barium Beryllium Bismuth Cadmium Calcium

(mg/L) Cerium Cesium

Pore Water Analysis (microgram per liter unless otherwise noted)

CCR-668 0-1 70 0.85 15 96 <0.05 <0.2 0.08 22 0.23 0.13

1-2 63 .67 24 91 <.05 <.2 .04 22 .24 .15

9-11 50 1.0 20 140 <.05 <.2 .03 31 .19 .23

9-11 28 .68 24 140 <.05 <.2 .03 30 .15 .20

18-20 18 .50 11 190 <.05 <.2 <.02 44 .08 .22

CCR-692 0-1 150 .61 26 87 <.05 <.2 .26 31 .59 .15

1-2 60 1.1 16 110 <.05 <.2 .08 33 .21 .16

9-11 45 2.0 15 180 <.05 <.2 .06 38 .20 .15

CCR-705 0-1 58 1.2 4.1 64 <.05 <.2 .68 19 .23 .06

1-2 100 1.0 6.0 68 <.05 <.2 .25 19 .44 .06

9-11 43 1.4 18 80 <.05 <.2 .07 20 .17 .04

Bulk Sediment Analysis (milligram per kilogram)

CCR-668 1-2 76,000 3.9 7.2 1,100 2.6 0.53 2.5 15,000 87 5.2

9-11 75,000 6.2 9.2 1,100 2.3 .54 4.1 16,000 87 4.8

CCR-692 1-2 70,000 4.2 5.2 1,200 2.5 .46 3.0 21,000 83 4.1

9-11 66,000 7.2 7.7 1,500 2.2 .46 4.6 36,000 72 4.1

CCR-705 1-2 76,000 5.3 7 1,200 2.5 .61 5.0 17,000 88 4.9

9-11 74,000 7.2 10 1,300 2.6 .64 9.2 20,000 92 4.5

Bulk and Residual Sediment Analysis (milligram per kilogram)

CCR-668

 Bulk sediment 1-2 74,000 3.8 9.0 1,100 2.6 0.30 2.6 15,000 96 5.1

 Residual sediment 67,000 3.6 6.7 902 1.80 .16 .44 10,000 52 4.6

 Residual (percent) 91 94 74 83 69 55 17 67 54 90

 Bulk sediment 9-11 72,000 6.1 12 1,100 2.5 .32 4.2 16,000 97 4.7

 Residual sediment 68,000 5.5 7.4 950 2.0 .15 .64 10,000 52 4.2

 Residual (percent) 94 90 64 83 80 47 15 66 53 89

CCR-705

 Bulk sediment 1-2 73,000 5.1 8.5 1,200 2.4 .41 5.2 17,000 96 4.8

 Residual sediment 64,000 4.4 5.2 940 1.8 .13 .52 9,700 52 4.2

 Residual (percent) 89 86 61 80 76 31 10 57 54 87

 Bulk sediment 9-11 73,000 7.2 14 1,300 2.7 .44 9.6 20,000 100 4.6

 Residual sediment 70,000 6.3 6.5 1,100 2.1 170 1.4 11,000 57 4.1

 Residual (percent) 96 88 48 87 78 39 14 58 57 90

66 Vertical Distribution of Trace Elements and Metallurgical Slag in Sediments, Lake Roosevelt, Washington, 2002
Table 7 67

Sediment core 

sampling site

Depth 

interval 

(cm)

Chromium Cobalt Copper Gallium Iron Lanthanun Lead Lithium Magnesium Manganese

Pore Water Analysis (microgram per liter unless otherwise noted)

CCR-668 0-1 <1 1.1 1.6 0.20 180 0.15 1.4 1.6 5.0 6,000

1-2 <1 .82 1.3 .20 1,300 .16 2.0 1.6 4.8 4,100

9-11 <1 .70 1.1 .10 1,400 .22 2.0 1.5 6.0 4,300

9-11 <1 .61 1.0 .10 5,600 .16 1.4 1.8 6.3 4,200

18-20 <1 .52 1.8 .08 3,400 .08 1.3 1.8 8.6 4,100

CCR-692 0-1 <1 1.0 4.2 .07 3,000 .42 6.5 1.4 9.0 2,100

1-2 <1 .45 1.9 <.05 160 .16 3.0 1.5 11 750

9-11 <1 .21 2.1 <.05 990 .17 3.8 1.2 15 260

CCR-705 0-1 <1 .62 3.8 <.05 120 .20 2.9 1.6 5.1 1,200

1-2 <1 .54 2.7 <.05 250 .44 8.0 1.8 5.2 890

9-11 <1 .39 1.0 <.05 410 .25 4.6 1.8 5.9 690

Bulk Sediment Analysis (milligram per kilogram)

CCR-668 1-2 83 15 69 18 41,000 51 110 33 14,000 1,100

9-11 91 15 110 17 40,000 60 210 32 14,000 1,000

CCR-692 1-2 68 20 75 16 37,000 50 130 28 15,000 620

9-11 73 12 130 15 38,000 47 250 28 21,000 550

CCR-705 1-2 92 14 91 17 42,000 57 230 33 14,000 860

9-11 110 13 100 17 39,000 74 430 32 16,000 700

Bulk and Residual Sediment Analysis (milligram per kilogram)

CCR-668

 Sediment 1-2 81.1 15 69 18 41,000 56 120 34 16,000 1,200

 Residual sediment 70.2 8.8 24 16 29,000 30 22 29 12,000 440

 Residual (percent) 86.56 59 34 90 71 53 19 86 75 39

 Sediment 9-11 88.0 15 110 17 40,000 66 220 33 15,000 1,000

 Residual sediment 77.9 8.2 32 16 28,000 31 27 28 12,000 410

 Residual (percent) 88.52 56 29 91 71 47 12 85 76 39

CCR-705

 Bulk sediment 1-2 88 14 90 17 42,000 63 250 33 16,000 850

 Residual sediment 75 7 20 15 26,000 30 22 28 11,000 360

 Residual (percent) 85 53 22 86 64 48 9.0 84 68 42

 Bulk sediment 9-11 110 13 100 17 40,000 81 460 32 17,000 710

 Residual sediment 99 8.0 28 16 28,000 35 41 28 12,000 396

 Residual (percent) 92 60 26 94 71 43 8.8 88 69 56

Table 7. Vertical distribution of concentrations of selected trace elements and major ions in pore water, bulk sediment, and residual sediment from shallow 

cores from sites CCR-668, CCR-692, and CCR-705, Lake Roosevelt, Washington, July 2003.—Continued

[Bulk and Residual Sediment Analysis: Replicate analysis of bulk sediment. Residual Sediment: Concentrations of residual sediment following 30 minute 

leach with 0.25 Molar hydroxylamine hydrochloride. Residual Percent: Residual as percentage of unleached bulk-sediment concentration. Abbreviations: cm, 

centimeter; mg/L, milligram per liter; <, less than; –, no data]
Sediment core

sampling site

Depth 

interval 

(cm)

Molybdenum Nickel Niobium Phosphorus Potassium Rubidium Scandlum Sodium Silver

Pore Water Analysis (micrograms er liter unless otherwise noted)

CCR-668 0-1 3.5 2.5 <0.2 0.1 1.6 5.0 5.9 3.4 <3

1-2 2.6 2.0 <.2 .1 1.7 5.0 6.6 2.4 <3

9-11 1.9 2.1 <.2 .02 2.3 6.7 7.5 3.3 <3

9-11 2.3 2.0 <.2 .04 2.1 6.1 9.4 3.4 <3

18-20 2.0 2.4 <.2 .01 2.9 7.7 9.0 4.6 <3

CCR-692 0-1 <2.0 3.0 <.2 .2 1.9 4.7 6.8 3.3 <3

1-2 <2.0 1.8 <.2 .04 2.3 4.8 7.4 3.2 <3

9-11 <2.0 2.0 <.2 .2 3.2 3.8 8.0 3.5 <3

CCR-705 0-1 <2.0 1.9 <.2 .05 1.1 3.7 4.6 2.2 <3

1-2 <2.0 1.6 <.2 .07 1.2 3.6 5.1 2.2 <3

9-11 2.8 1.3 <.2 .09 1.3 2.3 5.7 2.7 <3

Bulk Sediment Analysis (milligram per kilogram)

CCR-668 1-2 1.4 39 30 1,400 23,000 100 13 16,000 1.5

9-11 2.0 38 30 1,500 23,000 98 13 16,000 2.7

CCR-692 1-2 1.4 30 29 1,600 22,000 88 11 18,000 1.1

9-11 4.4 30 26 1,500 21,000 85 11 16,000 2.6

CCR-705 1-2 1.4 37 34 1,700 24,000 100 13 16,000 2.0

9-11 3.8 37 33 1,700 24,000 99 13 17,000 .16

Bulk and Residual Sediment Analysis (milligram per kilogram)

CCR-668

 Bulk sediment 1-2 1.7 42 29 1,400 24,000 99 13 17,000 –

 Residual sediment 1.3 27 17 400 21,000 94 12 15,000 –

 Residual (percent) 78 65 58 28 88 95 94 85 –

 Bulk sediment 9-11 2.2 40 29 1,600 24,000 97 12 18,000 –

 Residual sediment 1.5 26 16. 340 22,000 93 12 16,000 –

 Residual (percent) 68 65 57 22 92 96 97 90 –

CCR-705

 Bulk sediment 1-2 1.9 39 32 1,700 24,000 100 12 18,000 –

 Residual sediment 1.5 24 17 310 20,000 90 11 15,000 –

 Residual (percent) 79 61 52 18 84 90 91 83 –

 Bulk sediment 9-11 4.5 39 32 1,800 24,000 99 12 19,000 –

 Residual sediment 2.4 25 19 310 23,000 98 12 17,000 –

 Residual (percent) 53 64 58 17 94 98 98 90 –

Table 7. Vertical distribution of concentrations of selected trace elements and major ions in pore water, bulk sediment, and residual sediment from shallow 

cores from sites CCR-668, CCR-692, and CCR-705, Lake Roosevelt, Washington, July 2003.—Continued

[Bulk and Residual Sediment Analysis: Replicate analysis of bulk sediment. Residual Sediment: Concentrations of residual sediment following 30 minute 

leach with 0.25 Molar hydroxylamine hydrochloride. Residual Percent: Residual as percentage of unleached bulk-sediment concentration. Abbreviations: cm, 

centimeter; mg/L, milligram per liter; <, less than; –, no data]

68 Vertical Distribution of Trace Elements and Metallurgical Slag in Sediments, Lake Roosevelt, Washington, 2002
Sediment core

sampling site

Depth 

interval 

(cm)

Sulfate Tantalium Thallium Thorium Titanium Uranium Vanadium Yttrium Zinc

Pore Water Analysis (microgram per liter unless otherwise noted)

CCR-668 0-1 3 <0.02 <0.1 <0.2 1.2 0.33 1.3 0.19 6.6

1-2 <2 <.02 <.1 <.2 1.0 .26 1.9 .22 3.8

9-11 <2 <.02 .2 <.2 .50 .35 1.1 .44 26

9-11 <2 .05 .1 <.2 .90 .30 1.4 .39 3.4

18-20 <2 .05 <.1 <.2 .80 .33 .60 .26 40

CCR-692 0-1 <2 <.02 <.1 <.2 3.7 .59 1.2 .41 13

1-2 <2 <.02 <.1 <.2 1.3 .50 1.1 .20 3.7

9-11 <2 <.02 <.1 <.2 1.4 .54 1.6 .35 4.2

CCR 705 0-1 7 < .02 .1 <.2 1.2 .16 .7 .20 12

1-2 <2 <.02 .1 <.2 1.7 .17 1.0 .42 10

9-11 <2 <.02 <.1 <.2 <.50 .22 1.0 .30 4.9

Bulk Sediment Analysis (milligram per kilogram)

CCR-668 1-2 – 1.6 0.97 14 3,600 3.8 100 26 430

9-11 1.7 1.7 14 3,600 4.0 100 39 540

CCR-692 1-2 – 1.5 .91 12 3,300 3.9 90 25 540

9-11 – 1.4 1.2 11 3,000 5.3 91 27 960

CCR-705 1-2 – 1.8 1.0 14 3,500 3.9 110 33 650

9-11 – 1.9 1.4 14 3,500 4.4 110 50 980

Bulk and Residual Sediment Analysis (milligram per kilogram)

 CCR-668

 Bulk sediment 1-2 – – 1.0 16 3,900 4.0 100 29 420

 Residual sediment – – .72 14 3,700 2.1 88 16 140

 Residual (percent) – – 70 88 96 53 84 55 32

 Bulk sediment 9-11 – – 1.8 15 3,800 4.3 110 43 520

 Residual sediment – – .87 13 3,700 2.2 91 13 150

 Residual (percent) – – 50 87 96 51 86 31 28

CCR-705

 Bulk sediment 1-2 – – 1.1 15 3,700 4.1 110 37 600

 Residual sediment – – .76 14 3,400 2.3 85 11 140 

 Residual (percent) – – 70 89 92 56 81 30 23

 Bulk sediment 9-11 – – 1.5 15 3,900 4.4 110 58 900

 Residual sediment – – .84 14 3,800 2.6 96 15 230

 Residual (percent) – – 57 95 97 57 88 25 26

Table 7. Vertical distribution of concentrations of selected trace elements and major ions in pore water, bulk sediment, and residual sediment from shallow 

cores from sites CCR-668, CCR-692, and CCR-705, Lake Roosevelt, Washington, July 2003.—Continued

[Bulk and Residual Sediment Analysis: Replicate analysis of bulk sediment. Residual Sediment: Concentrations of residual sediment following 30 minute 

leach with 0.25 Molar hydroxylamine hydrochloride. Residual Percent: Residual as percentage of unleached bulk-sediment concentration. Abbreviations: cm, 

centimeter; mg/L, milligram per liter; <, less than; –, no data]

Table 7 69
70 Vertical Distribution of Trace Elements and Metallurgical Slag in Sediments, Lake Roosevelt, Washington, 2002

This page is intentionally blank.
Manuscript approved for publication, January 25, 2005

Prepared by the Publishing Group, U.S. Geological Survey, 

Washington Water Science Center, Tacoma, Washington

USGS Publishing staff

Bill Gibbs 

Bob Crist

Linda Rogers

Sharon Wahlstrom

For more information concerning the research in this report, contact the 

Washington Water Science Center Director, 

U.S. Geological Survey, 1201 Pacific Avenue – Suite 600 

Tacoma, Washington 98402

http://wa.water.usgs.gov
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