U.S. Department of the Interior

U.S. Geological Survey

Scientific Investigations Report 2012–5219

Prepared in cooperation with the U.S. Army Corps of Engineers

Grain-Size Distribution and Selected Major and Trace 

Element Concentrations in Bed-Sediment Cores from the 

Lower Granite Reservoir and Snake and Clearwater Rivers, 

Eastern Washington and Northern Idaho, 2010
Front cover:

Top left, The vibracorer (laying on boat deck) and its stabilizing frame on Lower Granite Reservoir, 

Washington, May 13, 2010. Photograph by Candice B. Adkins, U.S. Geological Survey. 

Top middle, Draining overlying water from a sediment core collected at Lower Granite Reservoir, 

Washington, May 11, 2010. Photograph by Candice B. Adkins, U.S. Geological Survey. 

Top right, Hydrologic technician K. Craig Weiss on Snake River upstream from U.S. Highway 12, 

Washington, May 19, 2010. Photograph by Jennifer T. Wilson, U.S. Geological Survey.

Bottom left, Hydrologist Ryan L. Fosness (left) and Research Hydrologist Peter C. Van Metre (right) 

preparing a core liner for the vibracorer on Lower Granite Reservoir, Washington, May 12, 2010. 

Photograph by Candice B. Adkins, U.S. Geological Survey. 

Bottom middle, Section of sediment core number 50 collected from Lower Granite Reservoir, 

Washington, at river mile 136.29, May 14, 2010. Photograph by Jennifer T. Wilson, U.S. Geological Survey. 

Bottom right, Hydrologists Rhonda J. Weakland (left) and Ryan L. Fosness (right) removing sediment 

core liner from core barrel at Lower Granite Reservoir, Washington, May 11, 2010. Photograph by Candice 

B. Adkins, U.S. Geological Survey. 

Back cover: Lower Granite Reservoir near Nisqually John Landing, Washington, April, 6, 2010. Photograph 

by Jennifer T. Wilson, U.S. Geological Survey. 
Grain-Size Distribution and Selected Major 

and Trace Element Concentrations in BedSediment Cores from the Lower Granite 

Reservoir and Snake and Clearwater 

Rivers, Eastern Washington and Northern 

Idaho, 2010

By Christopher L. Braun, Jennifer T. Wilson, Peter C. Van Metre, 

Rhonda J. Weakland, Ryan L. Fosness, and Marshall L. Williams

Prepared in cooperation with the U.S. Army Corps of Engineers

Scientific Investigations Report 2012–5219

U.S. Department of the Interior

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

KEN SALAZAR, Secretary

U.S. Geological Survey

Marcia K. McNutt, Director

U.S. Geological Survey, Reston, Virginia: 2012

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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:

Braun, C.L., Wilson, J.T., Van Metre, P.C., Weakland, R.J., Fosness, R.L., and Williams, M.L., 2012, Grain-size 

distribution and selected major and trace element concentrations in bed-sediment cores from the Lower Granite 

Reservoir and Snake and Clearwater Rivers, eastern Washington and northern Idaho, 2010: U.S. Geological Survey 

Scientific Investigations Report 2012–5219, 81 p.
iii

Contents

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

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

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

Previous Studies ..................................................................................................................................2

Multibeam Echosounding Bathymetric Survey .....................................................................2

Underwater Video Map Survey ................................................................................................5

Methods ..........................................................................................................................................................5

Collection of Cores ...............................................................................................................................5

Site Selection ..............................................................................................................................5

Tool Selection ..............................................................................................................................9

Coring ..........................................................................................................................................11

Subsampling and Description of Cores .................................................................................15

Analytical Methods ............................................................................................................................15

Grain Size ...................................................................................................................................15

Major and Trace Elements ......................................................................................................16

Quality Assurance and Quality Control ..........................................................................................16

Grain-Size Distribution ...............................................................................................................................17

Major and Trace Element Concentrations ..............................................................................................22

Summary .......................................................................................................................................................26

References Cited .........................................................................................................................................27

Appendixes

1. Distance from Bank and Elevation Data for Cross Sections 17, 18, and 24 .....................29

2. Grain-Size Data from Bed-Sediment Core Samples ............................................................45

3. Analytical Data for Major and Trace Elements in Bed-Sediment Core Samples ............59

4. Quality-Assurance and Quality-Control Data for Major and Trace Elements in 

Bed-Sediment Core Samples ...................................................................................................69

Figures

1. Map showing study area and sediment coring locations in Lower Granite 

Reservoir and the Snake and Clearwater Rivers, eastern Washington and 

northern Idaho, 2010 ....................................................................................................................3

2. Map showing A, Bathymetry from river mile 130 to river mile 142 of Lower 

Granite Reservoir and the Snake River and from river mile 0 to river mile 2 of the 

Clearwater River, eastern Washington and northern Idaho, and B, multibeam 

bathymetry overlying imagery showing geomorphologic features such as sand 

dunes, a scour hole, and rock outcrop between river miles 140 and 142 .........................4

3. Map showing facies of Lower Granite Reservoir and the Snake and Clearwater 

Rivers in eastern Washington and northern Idaho derived from A, video points 

(to determine sediment size and embeddedness) from the underwater video 

mapping (UVM) survey recorded at B, discrete increments along sections and 

dredge-material deposit areas used in conjunction with C, a bathymetric map 

created using multibeam echosounding (MBES) survey results, and composite 

UVM and MBES results shown enlarged as inset D .............................................................6
iv

4. Photograph showing pontoon boat with A-frame at Lower Granite Reservoir, 2010 .....10

5. Photographs showing different bed-sediment coring tools and procedures, 

including: A, a box corer, B, a box core, C, measurement of sediment-core

 thickness, D, components of a short aluminum gravity corer, and E, draining 

water overlying a bed-sediment core by cutting the liner with a tubing cutter ..............12

6. Photographs showing U.S. Geological Survey personnel A, lowering piston corer 

into the water and B, preparing to remove a bed-sediment core from the steel 

core barrel ..................................................................................................................................13

7. Photographs showing use of vibracoring system A, use of vibracorer with steel 

core barrel and polybuterate liner, B, use of vibracorer with aluminum liner and 

no barrel, C, vibracoring frame resting on the deck of the boat, D, preparation for 

deployment of vibracorer, and E, lowering of vibracorer inside frame ............................14

8. Photograph showing bed-sediment core 38 collected at river mile (RM) 130.44 

showing two sections of the core with distinct grain sizes for core intervals 

above and below a depth of 101.4 centimeters (cm) and intervals where grain-size 

samples were collected ...........................................................................................................16

9. A, Consolidation of data from various data-collection methods, including: facies 

map (derived from underwater video map survey results), bathymetry (derived 

from multibeam echosounding survey results), and grain-size data from surficial 

sediment coring and laser projection to generate B, a composite map of these 

data layers ..................................................................................................................................18

10. Percent silt and clay in surficial-sediment samples obtained from bed-sediment 

cores collected in Lower Granite Reservoir and the Snake and Clearwater Rivers, 

eastern Washington and northern Idaho, 2010 ....................................................................19

11. Comparison of grain-size distribution (as it relates to results from bed-sediment 

accumulation surveys done by the U.S. Army Corps of Engineers in 1995 and 

2008) in bed-sediment cores collected near the confluence of the Snake and 

Clearwater Rivers at A, cross-section 17, B, cross-section 18, and C, crosssection 24, eastern Washington and northern Idaho, 2010 ................................................20

12. Graphs showing concentrations of selected major and trace elements with 

depth (where a depth of 0 centimeters is the top of the core) in selected bedsediment cores collected in Lower Granite Reservoir, the Snake and Clearwater 

Rivers, and the confluence of the Snake and Clearwater Rivers, eastern 

Washington and northern Idaho, 2010 ...................................................................................23

13. Graphs showing comparison of percent silt and clay to selected major and 

trace element concentrations from bed-sediment core samples collected in 

Lower Granite Reservoir, the Snake and Clearwater Rivers, and the confluence of 

the Snake and Clearwater Rivers, eastern Washington and northern Idaho, 2010 .......25

Table

1. Bed-sediment core samples collected from the Lower Granite Reservoir and 

Snake and Clearwater Rivers in eastern Washington and northern Idaho, 2010 .............7
v

Conversion Factors

SI to Inch/Pound

Multiply By To obtain

Length

centimeter (cm) 0.3937 inch (in.)

millimeter (mm) 0.03937 inch (in.)

meter (m) 3.281 foot (ft) 

kilometer (km) 0.6214 mile (mi)

meter (m) 1.094 yard (yd) 

Inch/Pound to SI

Multiply By To obtain

Length

inch (in.) 2.54 centimeter (cm)

inch (in.) 25.4 millimeter (mm)

foot (ft) 0.3048 meter (m)

mile (mi) 1.609 kilometer (km)

Volume

cubic yard (yd3

) 0.7646 cubic meter (m3) 

Flow rate

cubic foot per second (ft3

/s) 0.02832 cubic meter per second (m3/s)

Vertical coordinate information is referenced to the North American Vertical Datum of 1988 

(NAVD 88).

Horizontal coordinate information is referenced to North American Datum of 1983 (NAD 83).

Grain-Size Distribution and Selected Major and Trace 

Element Concentrations in Bed-Sediment Cores from 

the Lower Granite Reservoir and Snake and Clearwater 

Rivers, Eastern Washington and Northern Idaho, 2010

By Christopher L. Braun, Jennifer T. Wilson, Peter C. Van Metre, Rhonda J. Weakland, Ryan L. Fosness, and 

Marshall L. Williams

Abstract

Lower Granite Dam impounds the Snake and Clearwater 

Rivers in eastern Washington and northern Idaho, forming 

Lower Granite Reservoir. Since 1975, the U.S. Army Corps 

of Engineers has dredged sediment from the Lower Granite 

Reservoir and the Snake and Clearwater Rivers in eastern 

Washington and northern Idaho to keep navigation channels 

clear and to maintain the flow capacity. In recent years, other 

Federal agencies, Native American governments, and special 

interest groups have questioned the negative effects that 

dredging might have on threatened or endangered species. To 

help address these concerns, the U.S. Geological Survey, in 

cooperation with the U.S. Army Corps of Engineers, collected 

and analyzed bed-sediment core samples (hereinafter cores) 

in Lower Granite Reservoir and impounded or backwater 

affected parts of the Snake and Clearwater Rivers. Cores were 

collected during the spring and fall of 2010 from submerged 

sampling locations in the Lower Granite Reservoir, and Snake 

and Clearwater Rivers. A total of 69 cores were collected by 

using one or more of the following corers: piston, gravity, 

vibrating, or box. From these 69 cores, 185 subsamples 

were removed and submitted for grain size analyses, 50 of 

which were surficial-sediment subsamples. Fifty subsamples 

were also submitted for major and trace elemental analyses. 

Surficial-sediment subsamples from cores collected from sites 

at the lower end of the reservoir near the dam, where stream 

velocities are lower, generally had the largest percentages 

of silt and clay (more than 80 percent). Conversely, all of 

the surficial-sediment subsamples collected from sites in the 

Snake River had less than 20 percent silt and clay. Most of 

the surficial-sediment subsamples collected from sites in the 

Clearwater River contained less than 40 percent silt and clay. 

Surficial-sediment subsamples collected near midchannel at 

the confluence generally had more silt and clay than most 

surficial-sediment subsamples collected from sites on the 

Snake and Clearwater Rivers or even sites further downstream 

in Lower Granite Reservoir. Two cores collected at the 

confluence and all three cores collected on the Clearwater 

River immediately upstream from the confluence were 

extracted from a thick sediment deposit as shown by the cross 

section generated from the bathymetric surveys. The thick 

sediment deposits at the confluence and on the Clearwater 

River may be associated with floods in 1996 and 1997 on the 

Clearwater River. 

Fifty subsamples from 15 cores were analyzed for major 

and trace elements. Concentrations of trace elements were 

low, with respect to sediment quality guidelines, in most cores. 

Typically, major and trace element concentrations were lower 

in the subsamples collected from the Snake River compared 

to those collected from the Clearwater River, the confluence 

of the Snake and Clearwater Rivers, and Lower Granite 

Reservoir. Generally, lower concentrations of major and trace 

elements were associated with coarser sediments (larger than 

0.0625 millimeter) and higher concentrations of major and 

trace elements were associated with finer sediments (smaller 

than 0.0625 millimeter). 

Introduction

The Lower Granite Dam impounds the Snake and 

Clearwater Rivers in eastern Washington and northern Idaho. 

Backwater from Lower Granite Reservoir extends to just 

upstream from the confluence of the Snake and Clearwater 

Rivers. The Snake and Clearwater Rivers transition at their 

confluence from free-flowing water to backwater caused by 

the Lower Granite Dam, and backwater marks the upstream 

extent of the reservoir pool. Delta deposits of bed-sediment 

material form as velocity and transport capacity diminish 

where streams enter the reservoir pool. In addition to 

deltaic deposition of primarily coarse sediments, processes 

in reservoirs include deposition of fine sediments from 

homogeneous flow, and transport and deposition of sediment 

from stratified flow (Fan and Morris, 1992, p. 355). Since its 

impoundment in 1975, 2.6 million cubic yards (2.0 million 
2 Grain-Size Distribution and Selected Major and Trace Element Concentrations in Bed-Sediment Cores

cubic meters) of sediment have been deposited annually 

into Lower Granite Reservoir and the Snake and Clearwater 

Rivers that flow into the reservoir (U.S. Army Corps of 

Engineers, 2003). The Snake River continues downstream 

from Lower Granite Dam; upstream from the confluence of 

the Snake and Columbia Rivers, the USACE operates three 

additional dams on the Snake River as part of the Snake 

River System (U.S. Army Corps of Engineers, 2002) (fig. 1). 

Historically, the USACE dredged sediment from the Snake 

River System, including Lower Granite Reservoir, to keep 

navigation channels clear and to maintain the flow capacity. 

Increases in reservoir stage in Lower Granite Reservoir 

caused by sedimentation also reduce the effectiveness 

of the levees protecting Clarkston, Wash., and Lewiston, 

Idaho, from flooding (Greg Teasdale, U.S. Army Corps of 

Engineers, written commun., 2011). In recent years, other 

Federal agencies, Native American governments, and special 

interest groups have questioned the negative effects that 

dredging might have on threatened or endangered species. 

The negative effects of dredging might include biological 

effects (on distribution, behavior, migration, feeding, 

spawning, development, and fish injury), physical effects (on 

disturbance, displacement, avoidance, entrainment, burial, 

noise, sedimentation, turbidity, suspended sediments, and 

habitat and food source modification), and water-quality 

effects (on acute toxicity, bioavailability, bioaccumulation, and 

exposure pathways) (U.S. Army Corps of Engineers, 2004). 

To address these concerns, the USACE initiated a 

multiyear project to assess the current status of sediment 

deposition in the reservoir and to explore alternative sediment 

control measures. The multiyear project included surveys 

of the sedimentary structures (bedforms) of Lower Granite 

Reservoir. Bed-sediment core samples (hereinafter cores) were 

collected by the U.S. Geological Survey in cooperation with 

the USACE during the spring and fall of 2010. A multibeam 

echosounding (MBES) bathymetric survey during fall 2009 

and winter 2010 and an underwater video map (UVM) survey 

of sediment facies during fall 2009 and winter 2010, also part 

of the multiyear study (Williams and others, 2012), were used 

to help interpret surficial sedimentary structures (bedforms) in 

the study area. The MBES and UVM surveys are described in 

detail by Williams and others (2012). The data from all three 

surveys will be used to model flood hydraulics and sediment 

transport and to make biological assessments in support of 

the USACE Programmatic Sediment Management Plan (U.S. 

Army Corps of Engineers, 2003).

Purpose and Scope

This report describes the results from cores collected in 

the Lower Granite Reservoir and the Snake and Clearwater 

Rivers impounded by the reservoir during spring 2010 and 

fall 2010. Specifically, the grain-size distribution of surficialsediment subsamples from cores collected underwater in 

Lower Granite Reservoir, the Snake and Clearwater Rivers, 

and the confluence of these two rivers are described, along 

with the down-core grain-size distribution in cores collected 

at or near the confluence of the Snake and Clearwater Rivers. 

Grain-size analyzes are compared with results from previous 

surveys to assess the predominant surficial sediment grainsize classes and how they relate to bed-sediment accumulation 

history, surficial sedimentary structures (bedforms), and 

embeddedness (degree to which gravel, cobble, boulders, or 

snags are sunken into the silt, sand or clay of a river or lake 

bottom) in Lower Granite Reservoir, the Snake and Clearwater 

Rivers, and the confluence of these two rivers. Results from 

the grain-size analyses were used to provide a quantitative 

mechanism for verification of the facies map generated 

from the UVM surveys done by Williams and others (2012). 

Selected major and trace element concentrations measured in 

subsamples of cores also are discussed.

Previous Studies

Multibeam Echosounding Bathymetric Survey

During fall 2009 and winter 2010, the U.S. Geological 

Survey (USGS), in cooperation with the USACE, conducted 

a hydrographic survey using a MBES to develop a digital 

elevation dataset on 12 river miles (RM) of Lower Granite 

Reservoir and the Snake River, and 2 RM of the Clearwater 

River upstream from the confluence with the Snake River 

(figs. 1 and 2) (Williams and others, 2012). The confluence 

of the Snake and Clearwater Rivers is upstream from the 

Lower Granite Dam and is where the rivers transition from 

free-flowing to backwater. Data from the survey will be used 

by the USACE to better understand and predict sediment 

transport and deposition in the reservoir as part of its 

Programmatic Sediment Management Plan (U.S. Army Corps 

of Engineers, 2003). The digital elevation dataset also can 

be used to display river-bed elevation and geomorphology 

such as scour holes, rock outcrops, and bedforms like ripples 

and dunes. This survey represents a snapshot-in-time of 

benthic geomorphology that can rapidly change because of 

fluctuations in reservoir stage, river discharge, and boat traffic. 

The MBES bathymetric survey was conducted from 

RM 130 to RM 142 on the Lower Granite Reservoir and 

Snake River and from RM 0 to RM 2 on the Clearwater 

River (fig. 2A). The survey mapped the full width of the 

river except areas along banks that were inaccessible to 

the boat or too shallow (less than 10 meters) to be measured 

with echosounding equipment. The survey was conducted in 

1-mile segments, and the resulting datasets were composited 

to provide a continuous digital elevation dataset of the 

reservoir and rivers. The primary purpose for these data is 

to support the USACE’s sediment transport modeling effort. 

However, these data also can provide a visual representation 

of bed geomorphology, which may be used for habitat 

assessments and other purposes. Figure 2B shows a twodimensional overhead view of part of the surveyed area, 

which includes areas of sand dunes, a scour hole, basalt 

outcrop, and areas where bed material was removed for 

levee construction.
117°30' 117°20' 117°10' 117°00'

46°40'46°35'46°30'46°25'

Lewiston

Clarkston

WASHINGTON

Lower Granite Reservoir Lower Granite Reservoir

Snake River

Snake RiverSnake River

39 38

37

41

40

45

4443 48

47

46

30B

25

26

27

23

22

19

20

21

24

29

28

33 32

31

36

35

34

38A

LOWERGRANITEDAM

IDAHO

52

1

89

88

87A

81

80

78

73 

5

82

70

66

62

60

56

53

50

59

57 72

85 86 84

79

75 76

74

65

67

69

68

71

3

2

4

6

64

63

61

58

54

55

51

49

87B

77

Lower Granite Reservoir

Snake River

CC

See Inset

Confluence

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Snake

River

Clearwater River

Studyarea

WASHINGTON

OREGON IDAHO

MONTANA

WYOMING

Grande Ronde River

13342500

Snake River

PACIFIC OCEAN

Columbia River

HELLSCANYONDAM

ICE HARBOR

LOCK AND DAM

LITTLE GOOSE

LOCK AND DAM

LOWER

MONUMENTAL

DAM

Imnaha

River

Salmon

River

0 1 2 0 1 

EXPLANATION

Multibeam echo sounding survey (MBES) extent

Bed-sediment core sample site and identifier (table 1)

77

! RM 139.64 River mile

 designation 13342500

U.S. Geological Survey streamflow- gaging station and station number

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RM 0.41

RM 0.28

RM 141.21

RM 140.75

RM 139.29

RM 138.94

RM 138.52

RM 138.07

RM 140.51

RM 140.22

RM 139.64

RM 139.43

RM 137.17

RM 136.69

RM 136.29

RM 135.15

RM 133.98

RM 130.44

RM 132.05

RM 128.27

RM 108.31

RM 111.24

RM 114.92

RM 119.56

RM 121.42

RM 136.29

Base from U.S. Geological Survey 1:100,000-scale digital dataAerial imagery from National Agriculture Imagery Program, 2009Universe Transverse Mercator projection, zone 11North American Datum of 1983

Figure 1. Study area and sediment coring locations in Lower Granite Reservoir and the Snake and Clearwater Rivers, eastern Washington and north

Idaho, 2010.
Figure 2. A, Bathymetry from river mile 130 to river mile 142 of Lower Granite Reservoir and the Snake River and from river mile 0 to river mile 2 of th

Washington and northern Idaho, and B, multibeam bathymetry overlying imagery showing geomorphologic features such as sand dunes, a scour holeriver miles 140 and 142 (modified from Williams and others, 2012, p. 6). 

Lower Granite Reservoir

Snake River

Ins

A

B

Flow direction

Scour hole

pit for leveeconstruction

Basalt outcrop

Sand dunes

Prereservoir borrow

Scour hole

pit for leveeconstruction

Basalt outcrop

Sand dunes

Prereservoir borrow

0 1 2 KILOM

0 1 

RM 130

RM 131

RM 132

RM 133 RM 134

RM 135

RM 136

RM 137

RM 138

R

RM 139

RM 140

RM 14

RM 142

Base from U.S. Geological Survey 1:100,000-scale digital dataAerial imagery from National Agriculture Imagery Program, 2009Universe Transverse Mercator projection, zone 11North American Datum of 1983

Riverbed elevation, in feet 740 660

Multibeam extent and river mileU.S. Army Corps of Engineers Global Positioning System benchmark survey site

RM 135

EXPLANATION

WASHINGTON

IDAHO

N
Methods 5

Underwater Video Map Survey

UVM surveys were done by the USGS in cooperation 

with the USACE during fall 2009 and winter 2010 (Williams 

and others, 2012) to visually identify the surface substrate type 

and percent embeddedness by determining particle size and 

the extent to which coarse substrate is surrounded or covered 

by silt and clay particles less than 0.0625 mm in diameter 

(commonly referred to as “fines” [Guy, 1969]). UVM surveys 

provide georeferenced information about the type and size of 

sediment on the surface of the bed. This information was used 

to enhance the bathymetric data and create a surficial sediment 

facies map of the current sediment distribution within the 

study area. The sediment facies map provides information on 

benthic habitat characteristics, variability of surface substrate, 

sediment transition zones, and unrealized areas of preferred 

species-specific habitat.

The UVM surveys were done between RM 107.73 

and RM 141.78 on Lower Granite Reservoir and the Snake 

River and between RM 0.28 and RM 1.66 on the Clearwater 

River and at RM 139.29 at the confluence of the Snake and 

Clearwater Rivers. More than 900 video clips were recorded at 

discrete, equal-width increments (video points, fig. 3A) along 

61 historic USACE survey lines and 5 existing longitudinal 

dredge-material deposit sites established by the USACE 

(fig. 3B). Video clips were recorded using a high-resolution, 

color-video camera outfitted with two high-power laser 

pointers that had a constant 4-inch (102 millimeter) separation 

as a scale of reference to determine sediment grain size 

(fig. 3A). The camera was lowered through the water column 

until it was close to the sediment-bed surface; sediment size 

and percent embeddedness were estimated based on a visual 

inspection of the video by an experienced hydrologist.

Sediment sizes and categories were defined as bedrock, 

boulder, cobble, gravel, sand, rip-rap, and fines (silt and clay). 

Coarse substrates (boulder, cobble, and gravel) were combined 

into one category for the purposes of this study because the 

occurrence of these types of substrates can vary greatly over a 

small area (fig. 3D).

Historically, facies maps were created by collecting 

sediment samples from the bed of the water body and 

analyzing the samples for grain size and sediment type. 

The level of effort and cost for such an endeavor limits the 

number of samples that can be collected, resulting in the 

creation of a facies map with a large amount of interpolation. 

Coupling results from the UVM survey with results from 

the MBES bathymetric survey enables the creation of a high 

resolution facies map (fig. 3) superior to a map created using 

traditional methods. The video record captures the primary 

attributes of the substrate, such as bottom type, texture, 

small bedforms, disturbance indicators, unusual features, and 

embeddedness; it also provides verification of the sediment 

type identified from the MBES data. For bedforms that are 

greater than the camera’s field of view, especially in limited 

light conditions, the MBES bed-elevation data provide the 

fidelity to define larger geomorphological features. The 

bathymetric survey results can be used to identify bedform 

features that might otherwise be misinterpreted, on the basis 

of video analysis alone, such as a featureless bottom (Williams 

and others, 2012). 

Methods

Core samples were collected at 67 locations (at each 

of two locations, 2 core samples were collected) in Lower 

Granite Reservoir, the Snake and Clearwater Rivers, and 

the confluence of these two rivers using one or more of the 

following corers: piston, gravity, vibrating (also called a 

vibracore), or box. From these 69 cores, 185 subsamples 

were removed and submitted for grain size analyses, 50 of 

which were surficial-sediment subsamples. Surficial samples 

were not submitted for grain-size analysis from cores that 

had surficial layers made up of predominantly organic matter 

and detritus that were unsuitable for grain-size analysis. A 

total of 50 subsamples were also submitted for major and 

trace elemental analyses. The cores were collected in April, 

May, and October 2010 between RM 0.28 and 1.66 on the 

Clearwater River, between RM 108.31 and 138.94 on Lower 

Granite Reservoir, at RM 139.29 at the confluence of the 

Snake and Clearwater Rivers, and between RM 139.43 and 

141.21 on the Snake River (table 1). The collection of cores 

was attempted at 86 locations using a piston, gravity, box, or 

vibrating core sampler. 

Collection of Cores

All cores were collected from submerged sediment 

deposits using a 7.5-meter (m) long pontoon boat with a 

4.5-m A-frame (fig. 4). This boat has the advantages of 

(1) accommodating the use of a hydraulic winch to deploy 

box, gravity, and piston corers or a vibracorer; (2) providing 

sufficient height for recovery of long cores (up to 3.5 m); 

(3) providing plenty of workspace; and (4) providing a stable 

work environment that is minimally affected by high winds 

typical of the study area.

Site Selection

Locations for the collection of cores (fig. 1) included 

cross sections that were measured as part of the 1995 and 

2008 bed-sediment surveys done by the USACE (Greg 

Teasdale, U.S. Army Corps of Engineers, written commun., 

2010) (appendix 1). Core sampling locations were grouped 

closely together (2.9 cross sections per river mile) near the 

confluence of the Snake and Clearwater Rivers (RM 139.29). 

To investigate the relative sediment contributions from the 

Snake and Clearwater Rivers, cores samples were collected 

in the reach of the Snake River immediately downstream 

from the confluence of the Snake and Clearwater Rivers 

and in both rivers upstream from the confluence (fig. 1 

inset). Farther downstream from the confluence, extending 

through the Lower Granite Reservoir to Lower Granite Dam, 

sampling locations were more widely distributed (10 sections 

of Lower Granite Reservoir were sampled from RM 135.15 

to 108.31).
Area enlargedSnake River Lower Granite Reservoir Clearw

R

LOWER GRANITE DAM 

RM 107.73 RM 141.78 0 2.5 5 MILES

0 2.5 5 KILOMETERS

EXPLANATION

Average embeddedness, in percent

0 to 2021 to 4041 to 6061 to 8081 to 100

Discrete underwater video points along historic 

U.S. Army Corps of Engineers cross sections and transects

Video point showing boulder, cobble, and gravel 

embedded between 40 and 60 in silt and clay (fig. 3A)

Sediment categories (size, in millimeters)— Modified from Wentworth, 1922 and Guy, 1969

Bedrock

Boulder (greater than 256), cobble (greater than 64 and less than or equal to 256),

and gravel (greater than 2 and less than or equal to 64)

Sand (greater than 0.0625 and less than or equal to 2)Rip-rap (varies)Silt and clay (less than or equal to 0.0625) combined with any of the above four categoriesSilt and clay (less than or equal to 0.0625)

RM 139.64 River mile designation

RM 0.28

RM 139.29

RM 139.22

RM 139.64

RM 138.94

RM 139.43

RM 0.41

RM 053

RM 138.71

D

C

B

Base from U.S. Geological Survey 1:100,000-scale digital dataNational Elevation Dataset 10-meter digital elevation modelAerial imagery from National Agriculture Imagery Program, 2009Universe Transverse Mercator projection, zone 11North American Datum of 1983

Video point showing cobble and gravel,  embedded between 40 and 60 percent in  silt and clay

A

0 2 4 INCHES0 51 102 MILLIMETERS

N

N

N

Figure 3. Facies of Lower Granite Reservoir and the Snake and Clearwater Rivers in eastern Washington and northern Idaho derived from A, video p

sediment size and embeddedness) from the underwater video mapping (UVM) survey recorded at B, discrete increments along sections and dredge-mused in conjunction with C, a bathymetric map created using multibeam echosounding (MBES) survey results, and composite UVM and MBES results 

(modified from Williams and others, 2012).
Methods 7

Table 1. Bed-sediment core samples collected from the Lower Granite Reservoir and Snake and Clearwater Rivers in eastern 

Washington and northern Idaho, 2010. —Continued

[NAVD 88, North American Vertical Datum of 1988; m, meters; cm, centimeters; --, no USGS station number established because it was not possible to collect 

a core sample or the core sample was not submitted for analyses]

USGS station 

number

Bedsediment 

core 

sample 

site and 

core 

identifier

River 

mile

Collection 

date

Latitude

(decimal 

degrees)

Longitude

(decimal 

degrees)

Bottom 

elevation 

NAVD 88 

(m)

Type 

of core 

sampler

Core 

sample 

length 

(cm)

Water 

depth 

(m)

Number 

of grain 

size 

subsamples

Number 

of major 

and trace 

element 

subsamples

Clearwater River

462534117015500 1 0.28 5/14/2010 46.4258 117.03242 219 vibracore 21 4.5 2 0

462537117015600 2 0.28 5/13/2010 46.4269 117.03233 220 vibracore 172 4.1 3 0

462535117015700 3 0.28 5/14/2010 46.4265 117.03240 216 vibracore 134 3.8 6 0

462532117014900 4 0.41 5/13/2010 46.4256 117.03026 218 vibracore 52 5.8 2 0

462535117014800 5 0.41 5/14/2010 46.4263 117.03005 219 vibracore 55 4.5 4 0

-- 6 0.41 5/11/2010 46.4272 117.03004 217 vibracore 

and box

0 6.7 0 0

462527117011300 7 0.92 5/18/2010 46.4241 117.02025 220 box 2 4.9 1 0

462532117011101 9 0.92 5/13/2010 46.4254 117.01963 218 vibracore 55 6.4 3 3

462517117010300 10 1.16 5/13/2010 46.4214 117.01745 220 vibracore 110 4.4 4 0

462520117005900 11 1.16 5/18/2010 46.4223 117.01643 222 box1 3 2.7 1 0

462524117005900 12 1.16 5/13/2010 46.4233 117.01637 219 vibracore 37 4.6 2 0

462513117004900 13 1.36 5/18/2010 46.4204 117.01368 220 box1 4 4.2 1 0

462517117004900 14 1.36 5/18/2010 46.4213 117.01348 221 vibracore 57 3.4 3 0

462520117004700 15 1.36 5/18/2010 46.4223 117.01263 219 vibracore 61 4.2 5 0

462511117002800 16 1.66 5/18/2010 46.4197 117.00767 219 box1 3 5.3 1 0

462512117002500 17 1.66 5/18/2010 46.4201 117.00705 219 box1 3 5.0 1 0

462515117002400 18 1.66 5/18/2010 46.4208 117.00658 219 box1 3 4.4 1 0

Lower Granite Reservoir

463914117245400 19 108.31 4/7/2010 46.6538 117.41492 202 piston 213 22.9 3 0

463921117245200 20 108.31 4/7/2010 46.6558 117.41440 191 piston 308 33.5 3 0

463930117244800 21 108.31 4/7/2010 46.6585 117.41330 198 piston 49 26.2 3 0

463749117232500 22 111.24 4/7/2010 46.6304 117.39038 188 piston 172 36.0 3 0

463748117231500 23 111.24 4/7/2010 46.6301 117.38758 191 piston 169 33.5 3 0

463745117225500 24 111.24 4/6/2010 46.6292 117.38183 211 piston 32 11.3 2 0

463516117210100 25 114.92 4/7/2010 46.5877 117.35022 193 piston 49 31.7 3 0

463519117205200 26 114.92 4/7/2010 46.5886 117.34780 196 piston 179 29.0 3 0

463521117204600 27 114.92 4/7/2010 46.5892 117.34603 202 piston 264 21.9 4 0

463316117161800 28 119.56 4/6/2010 46.5543 117.27168 214 gravity 102 12.8 3 0

463318117161600 29 119.56 4/6/2010 46.5551 117.27120 202 gravity 96 21.0 3 0

463322117161000 30B 119.56 4/6/2010 46.5563 117.26935 197 gravity 19 27.1 2 0

463216117150001 31 121.42 4/6/2010 46.5378 117.24992 199 piston 167 25.9 3 13

463219117145900 32 121.42 4/6/2010 46.5387 117.24982 198 piston 91 27.7 3 0

463221117145700 33 121.42 4/6/2010 46.5393 117.24910 200 gravity 27 23.2 2 0

Table 1. Bed-sediment core samples collected from the Lower Granite Reservoir and Snake and Clearwater Rivers in eastern 

Washington and northern Idaho, 2010. 

[NAVD 88, North American Vertical Datum of 1988; m, meters; cm, centimeters; --, no USGS station number established because it was not possible to collect 

a core sample or the core sample was not submitted for analyses]
8 Grain-Size Distribution and Selected Major and Trace Element Concentrations in Bed-Sediment Cores

Table 1. Bed-sediment core samples collected from the Lower Granite Reservoir and Snake and Clearwater Rivers in eastern 

Washington and northern Idaho, 2010. —Continued

[NAVD 88, North American Vertical Datum of 1988; m, meters; cm, centimeters; --, no USGS station number established because it was not possible to collect 

a core sample or the core sample was not submitted for analyses]

USGS station 

number

Bedsediment 

core 

sample 

site and 

core 

identifier

River 

mile

Collection 

date

Latitude

(decimal 

degrees)

Longitude

(decimal 

degrees)

Bottom 

elevation 

NAVD 88 

(m)

Type 

of core 

sampler

Core 

sample 

length 

(cm)

Water 

depth 

(m)

Number 

of grain 

size 

subsamples

Number 

of major 

and trace 

element 

subsamples

Lower Granite Reservoir—Continued

462655117123600 34 128.27 4/9/2010 46.4485 117.21002 214 piston 266 9.1 5 0

-- 35 128.27 4/9/2010 46.4488 117.20862 206 box 2 18.6 0 0

-- 36 128.27 4/9/2010 46.4492 117.20662 201 box 3 22.9 0 0

-- 37 130.44 4/9/2010 46.4206 117.20688 211 box 4 12.5 0 0

462520117122001 38 130.44 5/12/2010 46.4220 117.20573 210 vibracore 178 14.6 6 6

462520117122001 38A 130.44 4/9/2010 46.4221 117.20558 210 gravity 65 14.3 3 0

462522117121800 39 130.44 5/12/2010 46.4227 117.20501 215 vibracore 164 10.1 4 0

462525117102600 40 132.05 5/12/2010 46.4238 117.1739 209 vibracore 173 12.5 4 0

462529117102800 41 132.05 5/12/2010 46.4247 117.1744 205 vibracore 8 19.1 1 0

462540117081100 43 133.98 5/12/2010 46.4278 117.13626 208 vibracore 140 16.8 4 0

462542117081100 44 133.98 5/12/2010 46.4284 117.13651 205 vibracore 4 19.1 1 0

-- 45 133.98 5/12/2010 46.4291 117.13659 206 box 0 16.2 0 0

462514117065400 46 135.15 5/13/2010 46.4205 117.11497 214 vibracore 124 9.8 4 0

462515117065401 47 135.15 5/13/2010 46.4208 117.11497 211 vibracore 124 12.8 3 3

462520117065300 48 135.15 5/12/2010 46.4223 117.11466 211 box 2 12.5 1 0

462456117052900 49 136.29 5/14/2010 46.4156 117.09128 217 vibracore 135 7.5 5 0

462501117052800 50 136.29 5/14/2010 46.4170 117.09121 216 vibracore 151 7.9 3 0

-- 51 136.29 5/14/2010 46.4184 117.09071 217 box 0 6.9 0 0

462510117053900 52 136.29 5/14/2010 46.4196 117.09420 215 vibracore 115 10.1 4 0

462506117050400 53 136.69 5/12/2010 46.4182 117.08449 215 vibracore 66 9.6 3 0

462509117050300 54 136.69 5/15/2010 46.4191 117.08418 214 vibracore 123 10.1 3 0

-- 55 136.69 5/15/2010 46.4201 117.08514 213 box 0 10.8 0 0

462520117042900 56 137.17 5/15/2010 46.4223 117.07477 217 gravity 20 7.8 1 0

462523117042900 57 137.17 5/15/2010 46.4232 117.07463 213 box 1 12.2 1 0

-- 58 137.17 5/15/2010 46.4236 117.07618 210 box 0 14.6 0 0

462540117033500 59 138.07 5/15/2010 46.4277 117.05961 218 box1 3 6.7 1 0

462542117033601 60 138.07 5/15/2010 46.4284 117.05988 217 vibracore 70 7.2 3 3

-- 61 138.07 5/11/2010 46.4299 117.06026 210 box 0 11.8 0 0

462541117030300 62 138.52 5/12/2010 46.4280 117.05092 220 vibracore 136 3.9 2 0

462546117030500 63 138.52 5/20/2010 46.4294 117.05130 216 piston 147 8.3 2 0

-- 64 138.52 5/11/2010 46.4305 117.04965 213 box 0 8.9 0 0

462536117023500 65 138.94 5/11/2010 46.4268 117.04306 220 vibracore 121 4.6 3 0

462542117024801 66 138.94 5/20/2010 46.4282 117.04665 215 piston 76 10.1 2 1

-- 67 138.94 5/11/2010 46.4291 117.04117 216 box 0 9.4 0 0
Methods 9

Three coring sites were sampled at most of the 

preselected sampling locations (table 1). Coring sites 

were positioned along each section of river or reservoir 

where samples were collected to maximize the following 

selection criteria: thickness of lacustrine sediment (based on 

bathymetric survey data), sampling of differing depositional 

environments, and spacing between coring locations. One 

of the coring locations typically was selected at or near the 

deepest point within the channel along each section sampled.

Tool Selection

The advantages and disadvantages of each coring 

tool were taken into account when determining the most 

appropriate tool for a given sample. One consideration is 

the thickness of sediment. In reservoirs with thick sediment 

deposits, such as Lower Granite Reservoir, gravity and piston 

corers as well as a vibracorer are used because they are able to 

collect a much longer core compared to a box corer. Gravity 

Table 1. Bed-sediment core samples collected from the Lower Granite Reservoir and Snake and Clearwater Rivers in eastern 

Washington and northern Idaho, 2010. —Continued

[NAVD 88, North American Vertical Datum of 1988; m, meters; cm, centimeters; --, no USGS station number established because it was not possible to collect 

a core sample or the core sample was not submitted for analyses]

USGS station 

number

Bedsediment 

core 

sample 

site and 

core 

identifier

River 

mile

Collection 

date

Latitude

(decimal 

degrees)

Longitude

(decimal 

degrees)

Bottom 

elevation 

NAVD 88 

(m)

Type 

of core 

sampler

Core 

sample 

length 

(cm)

Water 

depth 

(m)

Number 

of grain 

size 

subsamples

Number 

of major 

and trace 

element 

subsamples

Confluence

-- 68 139.29 5/19/2010 46.4247 117.03882 216 box 0 8.3 0 0

-- 69 139.29 5/11/2010 46.4252 117.03742 215 box 0 9.1 0 0

462535117020701 70 139.29 5/14/2010 46.4263 117.03522 220 vibracore 62 3.8 6 6

462537117020500 71 139.29 5/14/2010 46.4269 117.03468 220 vibracore 162 3.8 5 0

Snake River

462522117021500 72 139.43 5/19/2010 46.4228 117.03755 214 box 0.5 10.1 1 0

462522117021501 73 139.43 5/19/2010 46.4228 117.03757 213 box 2 11.3 1 1

-- 74 139.43 5/11/2010 46.4230 117.03597 216 box 0 9.3 0 0

-- 75 139.64 5/19/2010 46.4192 117.03712 218 box 0 5.9 0 0

-- 76 139.64 5/19/2010 46.4191 117.03618 214 vibracore 0 10.5 0 0

-- 77 139.64 5/19/2010 46.4192 117.03530 217 box 0 7.9 0 0

462440117021300 78 140.22 5/19/2010 46.4112 117.03693 218 box 0.5 4.4 1 0

-- 79 140.22 5/19/2010 46.4106 117.03628 212 box 0 11.4 0 0

462437117020601 80 140.22 5/19/2010 46.4104 117.03505 209 box 1 15.2 1 1

462426117021901 81 140.51 5/19/2010 46.4072 117.03855 215 box 3 9.9 1 1

462426117021600 82 140.51 10/13/2010 46.4072 117.03777 213 box1 3 11.9 1 0

462413117022101 84 140.75 10/13/2010 46.4037 117.03927 217 vibracore 110 7.3 5 5

462412117021801 85 140.75 10/13/2010 46.4036 117.03850 218 vibracore 75 7.9 4 4

-- 86 140.75 5/19/2010 46.4035 117.03692 218 box 0 6.7 0 0

462348117022801 87A 141.21 5/19/2010 46.3967 117.04110 218 vibracore 19 6.1 1 1

462348117022801 87B 141.21 10/13/2010 46.3965 117.0380 218 vibracore 84 7.3 4 0

462352117022101 88 141.21 5/19/2010 46.3978 117.03917 218 box 3 6.1 1 1

462348117021701 89 141.21 5/19/2010 46.3968 117.03803 217 box1 3 7.6 1 1

1

Box core sampler used after attempts to collect a vibracore or gravity core were unsuccessful.
10 Grain-Size Distribution and Selected Major and Trace Element Concentrations in Bed-Sediment Cores

Figure 4. Pontoon boat with A-frame at Lower Granite Reservoir, 2010.
Methods 11

and piston corers are capable of collecting a 3-m core that 

is 6.7 cm in diameter, whereas the vibracorer is capable of 

collecting a 3.2-m core that is 7.6 cm in diameter. The box 

corer, which is 14 (length) × 14 (width) × 20 (height) cm, 

provides a shorter core but collects more material for a given 

interval compared to the tubular gravity and piston corers, 

and also has the advantage of collecting a less-disturbed 

sample (figs. 5A and 5B). Box corers were used predominantly 

for reconnaissance purposes (particularly at sites that were 

not expected to have thick sediment deposits) because of 

the relative ease of use compared to the tubular samplers. 

However, in some cases, box cores were subsampled for grain 

size and major and trace elements on the boat at the coring 

location.

The choice between using a gravity or piston corer is 

influenced by multiple factors. Gravity corers likely collect 

a less disturbed core and are easier to use. As a result, 

gravity corers were used often, especially for reconnaissance 

purposes. However, gravity corers have one important 

limitation—core shortening. Core shortening refers to the 

thinning of sediment layers recovered relative to undisturbed 

sediment; it has been attributed to friction on the walls of the 

liner (Emery and Hulsemann, 1964). In addition to friction, 

the sediment in the gravity corer barrel must push water out 

the top through a check valve, which generates back pressure 

inside the liner. In 1998, a piston and a gravity core were 

collected side by side in White Rock Lake, Tex. (Van Metre 

and others, 2004). Both encountered prereservoir sediment and 

appeared to represent the complete sediment sequence on the 

basis of color banding in the cores. The thickness of lacustrine 

sediment in the gravity core was 122 cm compared to 206 cm 

in the piston core, a core shortening of 41 percent. Therefore, 

if quantifying total lacustrine thickness is a primary objective, 

as it was in this study, an alternative coring method to gravity 

coring should be used, or an accounting of core shortening 

should be done (Juracek, 1998). 

Vibrating core samplers (vibracorers) have an advantage 

over coring devices that sink (box corers), drop (gravity 

corers), or propel (piston corers) (Van Metre and others, 

2004); unlike these other samplers, the vibracorer generates 

a high frequency vibration that transfers more energy to the 

sediment—greatly reducing wall friction inside and outside of 

the tube used to collect the core. This results in longer, more 

representative cores. One disadvantage of vibracoring occurs 

when wall friction inside the tube (as the tube penetrates 

sediment) exceeds the bearing strength of the sediment 

causing the sediment inside the tube to stop moving even 

though the tube continues to penetrate the sediment. This 

can lead to intermediate layers of sediment being bypassed 

unbeknownst to the investigator; this effect is referred to 

as plugging or rodding. Additional drawbacks associated 

with vibracoring include the potential for resuspension of 

the top few centimeters of water-rich sediment and possible 

compaction of sand and organic-rich layers by the associated 

vibrations (Vibracoring Concepts, 2011).

Coring

One or more cores were collected at selected core 

sampling sites for grain size distribution analysis and for 

trace element analysis following procedures described by 

Shelton (1994). In most cases, only one core was collected 

unless the sediment thickness was less than expected based 

on the river-bed elevation and geomorphology from the 

bathymetric survey. In these instances, a second or even third 

core would often be collected, frequently using an alternative 

coring method. Latitude and longitude of the coring site were 

obtained from a global positioning system to ensure that the 

location being sampled was at or near the predetermined 

sampling location. The depth of water at each site was 

obtained using a fathometer, and the approximate thickness 

of sediment obtained in each core was measured (fig. 5C) and 

recorded.

The gravity corers used in this study had a steel barrel 

with a polybuterate liner or an aluminum core barrel with 

lead weight attached and a polybuterate liner held in place by 

a polyvinyl chloride flange and hose clamps (fig. 5D). Each 

liner had a check-valve attached to the top, which allowed 

water to escape during penetration and then closed to help 

retain sediment during recovery. A cutting head was attached 

to the bottom of the steel barrel to help protect the liner 

and penetrate firmer sediments. A core catcher was inserted 

at the bottom of the liner to help retain sediment during 

recovery. The corer typically was allowed to free fall during 

sample collection to maximize sediment recovery. During 

retrieval, the bottom of the core was immediately capped as 

it approached the water surface. The cap was taped on while 

the core was suspended vertically from the A-frame, and the 

core was removed from the barrel and stored upright until 

subsampling. Core liners were cut about 1 cm above the top 

of the sediment to drain any water overlying the sediment 

(fig. 5E) and then capped and taped to minimize disturbance 

during transport to the subsampling location. A small gravity 

corer with an aluminum core barrel (fig. 5D) was used as 

a reconnaissance tool to estimate sediment thickness and 

determine the predominant sediment type. Reconnaissance 

was particularly important in areas where little sediment 

thickness was expected.

The piston corer works like a syringe with the bottom cut 

off to create an open cylinder—the piston acts as the plunger 

and the core barrel acts as the outside of the syringe. The 

plunger (piston) is held in place just above the sediment and 

the outside of the syringe is pushed past the piston into the 

sediment. The piston corer used in this study was the same 

weight with the same barrel as the gravity corer. However, it 

contained a piston inside the liner connected to a trigger arm 

located above the corer and attached to the winch on the boat 

(figs. 6A and 6B). When the trigger weight suspended from 

the trigger arm reaches the bottom, the arm releases the corer 

allowing it to fall past the piston into the sediment. The piston 

should stop just above the top of the sediment by the cable 
12 Grain-Size Distribution and Selected Major and Trace Element Concentrations in Bed-Sediment Cores

lead weights

polybuterate

liner

check valve

aluminum 

core barrel

A B

C D

E

Figure 5. Different bed-sediment coring tools and procedures, including: A, a box corer, B, a box core, C, measurement of sedimentcore thickness, D, components of a short aluminum gravity corer, and E, draining water overlying a bed-sediment core by cutting the 

liner with a tubing cutter.
Methods 13

attached to the winch if the length of cable between the trigger 

arm and piston and the length of rope between the trigger arm 

and trigger weight were properly measured and the winch 

operator stopped lowering as soon as the trigger arm released 

the corer. As the barrel falls past the piston into the sediment, a 

strong vacuum is created below the piston, which enhances the 

recovery of sediment. The winch pulls the piston to the top of 

the corer, if it was not already there, and lifts the corer. Once 

out of water, the trigger arm and weight are disconnected from 

the cable. The methods associated with piston core retrieval 

and storage were comparable to those associated with gravity 

core retrieval and storage.

The vibracorer was used to collect cores from 

substrates with predominantly sand or larger particle sizes. 

The vibrating mechanism of the vibracorer, referred to as 

the vibrahead (fig. 7A), is powered by an external electrical 

source and generates 3,000 to 11,000 vibrations per minute. 

These vibrations cause a thin layer of material to mobilize 

along the inner and outer walls of the core barrel or liner, 

reducing friction and easing penetration into the substrate. 

Metal tubes conduct vibration energy best, with hard steel 

performing better than aluminum. Plastic tubes are poorer 

conductors than metals, but this disadvantage is partially 

offset by the reduced mass requiring vibration (Vibracoring 

trigger arm

support rope for 

trigger weight

A B

steel core 

barrel

lead weights

Figure 6. U.S. Geological Survey personnel A, lowering piston corer into the water and B, preparing to remove a bed-sediment core 

from the steel core barrel.
14 Grain-Size Distribution and Selected Major and Trace Element Concentrations in Bed-Sediment Cores

Figure 7. Use of vibracoring system A, use of vibracorer with steel core barrel and polybuterate liner, B, use of vibracorer with 

aluminum liner and no barrel, C, vibracoring frame resting on the deck of the boat, D, preparation for deployment of vibracorer, and 

E, lowering of vibracorer inside frame. 

vibrahead

steel core 

barrel

A B

D

E

aluminum 

liner

vibracorer

frame

C
Methods 15

Concepts, 2011). For this study, the same steel barrels 

and polybuterate liners used to collect the gravity and 

piston cores were used initially to collect the vibracores 

(fig. 7A). However, the vibracorer did not appear to be 

penetrating the sediment to the expected depth. This was 

likely due to a loss in vibration efficiency because of the 

small gap between the liner and the barrel. Therefore, a 

transition was made to using aluminum liners without a 

core barrel (fig. 7B). In order to keep the vibracorer from 

penetrating the sediment at an angle, a frame was constructed 

to house the vibracorer and ensure penetration perpendicular 

to the sediment surface (figs. 7A, 7B, and 7C (Vibracoring 

Concepts, 2011). The vibracorer frame was lowered from 

the front end of the pontoon boat using an onboard winch 

until the base of the frame was resting on the bottom 

sediment of the reservoir or river being sampled (figs. 7D

and 7E). Once a vibracore was collected (using an aluminum 

liner), a handsaw was used to remove most of the unused 

liner above the uppermost sediment layer in the core; any 

water that was collected above the top of the sediment in the 

core also escaped at this time. Because the aluminum core 

liner is opaque, locating the top of the sediment core was 

problematic. Therefore, using a handsaw, the liner was cut 

several centimeters above where the top of the sediment 

core was anticipated. The last few centimeters of liner above 

the top of the core were then removed using a tubing cutter 

(fig. 5E).

Subsampling and Description of Cores

Piston cores, gravity cores, and vibracores were held 

vertically during removal from the samplers and transported 

to the river bank or reservoir shore, where they were split 

lengthwise, photographed, described, and subsampled. Core 

extraction from bottom sediments is referred to as sampling, 

whereas the subdivision of each core into discrete intervals is 

referred to as subsampling. The cores were laid on the ground 

and split lengthwise using a circular saw to cut through most 

of the liner, cutting the rest of the liner with a utility knife, 

and then slicing the sediment with a stainless steel or Teflon 

spatula. The core was then split open next to a tape measure, 

photographed, and described. Descriptions included color, 

texture, odor, and the presence or absence of organic detritus 

and biota or other visible debris. Surficial sediment samples 

were designated as any sample that included some part of 

the top 5 cm of the core. Identification of the prereservoir 

land surface (if penetrated) was an important part of the 

description. Lacustrine sediments typically have a high water 

content (porosity of 70 to 90 percent) and are usually silt and 

clay, whereas prereservoir soils are drier or stickier compared 

to the overlying lacustrine sediment, and often have root hairs 

and gravel (sediment larger than 2.0 mm in diameter). The top 

of the prereservoir surface may also have a layer of decaying 

leaves and sticks.

After a core was described and photographed, one-half 

of the core was cut into sections and placed into a plastic 

core archival box. The sediment depths of each core section 

were noted on the core archival box. Archived cores were 

provided to the USACE in Walla Walla, Wash., for long-term 

storage. Samples for laboratory analyses were collected from 

the remaining one-half of the core. Samples were collected 

from each section of the core with a distinct grain size. For 

example, the sediment in core sample 38 collected on May 

12, 2010, changed at a depth of 101.4 cm from a gray colored, 

medium to fine–sized sand (0.25 to 0.125 mm in diameter) 

to dark brown silt and clay (fig. 8). Two to five samples were 

collected from most gravity cores, piston cores, and vibracores 

for grain-size analysis. One sample was collected from most 

box cores for grain-size analysis. The samples were collected 

by scooping the sediment out of the core liner at a selected 

depth interval with a Teflon spatula and transferring it to a 

sample container. Samples for grain-size analysis were placed 

in precleaned polypropylene jars. Samples for analysis of 

major and trace elements were placed in separate precleaned 

polypropylene jars. Each sample was labeled with the river 

mile, core identification, and depth interval of the core, in 

centimeters. Sampling tools were rinsed in tap water, soaked 

and washed with a brush in phosphate-free detergent, and 

rinsed again in tap water between samples.

Analytical Methods

Sediment samples were analyzed for grain size and 

selected major and trace elements. All samples selected for 

grain-size analysis were sent to the USGS Cascades Volcano 

Observatory Laboratory in Vancouver, Wash. Samples for 

major and trace element analyses were sent to the USGS 

Mineral Resources Program Analytical Laboratories in 

Denver, Colorado.

Grain Size

Two methods were used for grain-size analysis. For 

coarse material (sand-sized particle larger than 0.0625 mm in 

diameter), the wet sieve method was used (Pope and Ward, 

1998). For silt and clay sized particles, a Micromeritics 

SediGraph 5120 was used to perform a sedimentation 

technique (referred to hereinafter as the Meyer-Fisher 

sedimentation technique), which measures the gravity-induced 

settling rates of different size particles in a liquid with known 

properties as a means to provide grain-size information 

(Meyer and Fisher, 1997). Sand-fine separation and scale of 

size classes defined in Wentworth (1922) and Guy (1969) for 

gravel, sand, silt, and clay particles were followed.

A sand-fine separation was initially done to determine 

which grain-size classification method would be used. If less 

than 5 percent of the sample by weight was sand, then a total 

sand weight was reported, and the Meyer-Fisher sedimentation 

technique was used to analyze the silt and clay (fines). If the 

sample had less than 5 percent silt and clay by weight, then 

a total weight for the fines was reported, and the wet sieve 
16 Grain-Size Distribution and Selected Major and Trace Element Concentrations in Bed-Sediment Cores

method was used to analyze the coarse sediment. If the sample 

had enough material from both size classes, then a complete 

size analysis was performed. Because it was necessary to keep 

the material wet throughout the analysis, the decision for a 

complete size analysis was based on a visual determination 

by the technician performing the analysis. If the amount of 

silt and clay material was less than 5 percent, then generally 

there was not enough material to perform the Meyer-Fisher 

sedimentation technique (appendix 2). 

Major and Trace Elements

Freeze-dried sediment samples were analyzed for 

major and trace elements by the USGS Mineral Resources 

Program Analytical Laboratories in Denver, Colo., for the 

USGS National Water Quality Laboratory. Samples for 

major and trace element analyses were digested completely 

using a mixture of hydrochloric, nitric, perchloric, and 

hydrofluoric acids and analyzed by inductively coupled 

plasma–mass spectrometry (ICP–MS) (Briggs and Meier, 

2002). Concentrations of mercury were determined by 

continuous flow-cold vapor-atomic fluorescence spectrometry 

(CVAFS) (Hageman, 2007) (appendix 3).

Quality Assurance and Quality Control

Quality-control (QC) samples for the major and trace 

elements were analyzed to ensure the quality, precision, 

accuracy, and completeness of the dataset; no QC samples 

were analyzed for grain size. The QC samples for major and 

trace elements consisted of laboratory reagent blank samples, 

standard reference materials (SRMs), and replicate samples 

analyzed with each set of environmental samples (appendix 4). 

The Lower Granite Reservoir samples were analyzed for 

major and trace elements in two different sets. A “lower 

reporting limit” described by Taggart (2002, p. viii) as greater 

than or equal to “five times the standard deviation determined 

from the method blank” was used for major and trace 

elements. Major and trace element concentrations less than 

the respective lower reporting limits are hereinafter referred to 

as nondetections, and concentrations equal to or greater than 

the respective lower reporting limits are hereinafter referred to 

as detections.

At least one major or trace element was detected in 13 

percent of the blank analyses; cesium, niobium, and antimony 

were the most frequently detected trace elements. There were 

no detections in the blank analyses for 21 of the 38 elements. 

The laboratory analyzed SRMs, compared the values to 

Figure 8. Bed-sediment core 38 collected at river mile (RM) 130.44 showing two sections of the core with distinct grain sizes for core 

intervals above and below a depth of 101.4 centimeters (cm) and intervals where grain-size samples were collected.

Core description:

101.4 to 151 cm,

dark brown color,

clay with silt

Core description:

36 to 101.4 cm,

medium gray color,

fine to medium sand

Grain-size 

sample

collected at

105 to 108 cm

Grain-size 

sample

collected at

98 to 101 cm
Grain-Size Distribution 17

published or standard results, computed the percent recoveries, 

and noted unacceptable SRM recoveries that were 10 percent 

more or less than 100 percent recovery. The SRM results are 

used to assess bias for each analysis. Titanium recoveries 

were less than 90 percent in 13 of 16 SRM analyses, whereas 

gallium recoveries were greater than 110 percent in 11 of 

16 SRM analyses. Other elements with 50 percent or more 

unacceptable SRM recoveries included bismuth, cerium, 

and yttrium.

The laboratory analyzed two laboratory replicates in 

which the sample was split at the laboratory (appendix 4). 

Replicates provide information about variability in the 

analytical process, but results can be affected by sample 

heterogeneity, particularly when sediments are the sample 

media (Pirkey and Glodt, 1998). The relative percent 

difference (RPD) was computed between each pair of replicate 

analyses to provide a measure of precision using the equation: 

RPD = |C1 – C2|/((C1 + C2)/2) x 100, (1)

where 

C1 is the constituent concentration, in 

micrograms per gram, of one observed 

value; and 

C2 is the constituent concentration, in 

micrograms per gram, of a second 

observed value.

The overall average RPD for the major and trace element 

replicate analyses was 3.7 percent. The highest RPDs were for 

replicate analyses of antimony (88.8, 84.7, and 33.8 percent), 

followed by silver (29.4 percent). 

Grain-Size Distribution

Results from the three data collection techniques used 

in the multiyear study (MBES bathymetric survey map, 

facies map based on UVM survey results, and grain-size 

analyses of sediment cores) were consolidated to better 

understand the grain-size distribution. This data consolidation 

also provided information on variations in substrate type 

relative to embeddedness throughout the reach as well as 

the predominance of fines (silt and clay) in the backwateraffected area downstream from the confluence. It also 

provides an opportunity to interpret surficial sedimentary 

structures (bedforms) of Lower Granite Reservoir, the Snake 

and Clearwater Rivers, and the confluence of these two rivers 

(fig. 9).

Results from the grain-size analyses of sediment cores 

also provided a quantitative mechanism for verifying the 

facies map generated from the UVM surveys (Williams and 

others, 2012) (fig. 10). None of the 25 surficial sediment 

samples with less than 20.1 percent silt and clay (based 

on grain-size analysis) were located in areas that the facies 

map identified as having silt and clay size particles. Of the 

12 surficial sediment samples with greater than 80 percent 

silt and clay (based on grain-size analysis), 10 were located in 

areas that were identified as having silt and clay size particles 

based on the facies map; the two remaining samples were 

located in areas classified as sand on the facies map.

Percent silt and clay in surficial sediment samples 

obtained from bed-sediment cores collected in the Snake and 

Clearwater Rivers and Lower Granite Reservoir are shown in 

figure 10. Sites at the lower end of the reservoir, closest to the 

dam (sites 19–30) where stream velocities are lower, tended 

to have larger volumes of silt and clay compared to the other 

sites that were surveyed. All of the surficial sediment samples 

collected in the Snake River upstream from the confluence had 

less than 20 percent silt and clay. This is most likely because 

velocities in this reach of the Snake River are high enough to 

keep fine-grained (silt and clay) sediment particles entrained. 

Most of the surficial sediment samples collected in the 

Clearwater River (9 out of 13) contained less than 40 percent 

silt and clay; only one site (site 16) had more than 60 percent 

silt and clay, and this site was located in a near-bank, lowervelocity margin environment. Surficial sediment samples 

collected near midchannel at the confluence (site 70) tended 

to have more silt and clay than most surficial sediment sample 

collection sites on the Snake and Clearwater Rivers or even 

sites further downstream in Lower Granite Reservoir (sites 59, 

60, and 63). The turbulence and reduction in velocity induced 

by the confluence of the Snake and Clearwater Rivers likely 

caused these two rivers to drop much of their sediment load in 

this area. Of the remaining surficial sediment samples (those 

located downstream from site 70 and upstream from site 30), 

all but two (site 52, which is located in a low-velocity, nearshore environment and site 66, which is located on the inside 

of a bend in Lower Granite Reservoir) had less than 40 percent 

silt and clay.

Downcore grain-size data from cores collected near 

the confluence of the Snake and Clearwater Rivers were 

plotted (fig. 11) to explore grain-size variations in this 

transitional area from free flowing to backwater conditions. 

Of the four proposed coring locations at the confluence, 

cores could only be collected at two locations, sites 70 and 

71. Attempts at collecting box cores at the two remaining 

confluence sites, 68 and 69, resulted in nothing more than a 

trace amount of sand at site 69. Site 68 was located in an area 

identified as sand on the facies map and had visible dunes in 

the images generated from the MBES survey (Williams and 

others, 2012), so the inability to collect a core at this location 

was unexpected; rivers are dynamic systems and locations of 

dunes can change gradually over time or rapidly in response 

to storm events (Germanoski and Schumm, 1993). Site 69 was 

located in an area defined as boulder, cobble, and gravel on 

the facies map, so the inability to collect a core at this location 

was expected. 
Figure 9. A, Consolidation of data from various data-collection methods, including: facies map (derived from underwater video map survey results), 

multibeam echosounding survey results), and grain-size data from surficial sediment coring and laser projection to generate B, a composite map of th

!

!

!

EXPLANATION

Average embedde 20 to 40 40 to 60 80 to 100Discrete underwa U.S. Army Corp and transectsPercent silt and c coring location 0 to 20 40.1 to 60 60.1 to 80Video point show embedded betw clay (fig. 9A)

5

7366

Base from U.S. Geological Survey 1:100,000-scale digital dataAerial imagery from National Agriculture Imagery Program, 2009Universe Transverse Mercator projection, zone 11North American Datum of 1983

Bedrock

Boulder (greater than 256), cobble (greater than 64 and less  than or equal to 256), and gravel (greater than 2 and less  than or equal to 64)

Sand (greater than 0.0625 and less than or equal to 2)Rip-rap (varies)Silt and clay (less than or equal to 0.0625) combined with  any of the above four categoriesSilt and clay (less than or equal to 0.0625)

Sediment categories (size, in millimeters)— Modified from Wentworth, 1922 and Guy, 1969

B

1

72

73

70

66

71

3

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!

!!

1

72

5

73

70

66

71

3

!

! !

!

!

!

!

A

Lower Granite

Reservoir

Clearwater

River

Snake River!

Confluence

Confluence 0 2 4 INCHES

0 51 102 MILLIMETERS

N

N
Figure 10. Percent silt and clay in surficial-sediment samples obtained from bed-sediment cores collected in Lower Granite Reservoir and the Snake 

eastern Washington and northern Idaho, 2010.

117°30' 117°20' 117°10' 117°00

46°40'46°35'46°30'46°25'

!! !

!

!!

!

!!

!

!!!

!

!

!

!

!!

!! ! !

!!

!

! !

!!

!

!

!

! ! ! ! !

!

!

!

!

!

!

!

!

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!

!

!

!

!!

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!

1

89

88

87A

81

80

78

72 

5

82

73

70

66

60

56

53

50

59

57

71 3

54

49

52

63 !

Lower Granite Reservoir 

Snake River

See Inset

Confluence

Base from U.S. Geological Survey 1:100,000-scale digital dataAerial imagery from National Agriculture Imagery Program, 2009Universe Transverse Mercator projection, zone 11North American Datum of 1983 0 1 2 3 4 KILOMETERS

0 1 2 3 4 MILES

Lewiston

Clarkston

44

48

30B

25

26

27

23

22

19

20

21

!

43

33 !

!

WASHINGTON

IDAHO

Lower Granite Reservoir

Snake River

!!

!

!!

!!!

!

!

EXPLANATION

!!!!!

Percent silt and clay, measured at surficial  sediment-coring location, and core identifier 0 to 20 20.1 to 40 40.1 to 60 60.1 to 80 80.1 to 100

5

66

50

49

52

 Bedrock

 Boulder (greater than 256), cobble (greater than 64 and less than or equal to 256), and gravel (greater than 2 and less than or equal to 64) Sand (greater than 0.0625 and less than or  equal to 2)

 Rip-rap (varies) Silt and clay (less than or equal to 0.0625)  combined with any of the above four categories Silt and clay (less than or equal to 0.0625)Sediment categories (size, in millimeters)— Modified from Wentworth, 1922 and Guy, 1969
20 Grain-Size Distribution and Selected Major and Trace Element Concentrations in Bed-Sediment Cores

73

Gravel

Very coarse sand

Coarse sand

Medium sand

Fine sand

Very fine sand

Silt/clay

2008

1995

EXPLANATION

Bed-sediment accumulation

 survey, by year performed

Grain size in core samples

Bathymetric survey 

 line showing coring

 location 

Depth interval where grain 

 size was analyzed

0

50

100

150

Depth, in centimeters

Core 71

Bottom of core at 162

centimeters

0 50 100

Cumulative percent

0

20

40

60

Depth, in centimeters

0 50 100

Cumulative percent

Core 70

Bottom of core at 62

centimeters

212.0

214.0

216.0

218.0

220.0

222.0

224.0

0 160 360 560 760

Cross-section 17 - River mile (RM) 139.29

Proposed coring location (68)

Core 70

Core 71

Proposed coring location (69)

Elevation, in meters

Distance from left bank, in meters

A

Snake River

Lower Granite

Reservoir Clearwater

River

cross-section 17 - RM 139.29

cross-section 18

RM 139.43

cross-section 24

RM 0.28

72 73

74

1

2

3

68

69

70

71

N

Confluence

Figure 11. Comparison of grain-size distribution (as it relates to results from bed-sediment accumulation surveys done by the U.S. 

Army Corps of Engineers in 1995 and 2008) in bed-sediment cores collected near the confluence of the Snake and Clearwater Rivers at 

A, cross-section 17, B, cross-section 18, and C, cross-section 24, eastern Washington and northern Idaho, 2010.
Grain-Size Distribution 21

0

50

100

0 50 100

Cumulative percent

Core 3

Bottom of core at 134

centimeters

0

50

100

150

Depth, in centimeters

0 50 100

Cumulative percent

Core 2

Bottom of core at 172

centimeters

0

10

Depth, in

20

centimeters

0 50 100

Cumulative percent

Core 1

Bottom of core at 21

centimeters

214.0

216.0

218.0

220.0

222.0

0 100 200 300 400

Cross-section 24 - River mile 0.28 Core 1 Core 2 Core 3

Elevation, in meters

Distance from left bank, in meters

C

212.0

214.0

216.0

218.0

220.0

222.0

224.0

210.0

0 100 200 300

Cross-section 18 - River mile 139.43 Core 72 Core 73 Proposed coring location (74)

Elevation, in meters

Distance from left bank, in meters

B

0 50 100

Cumulative percent

Core 73

Bottom of core at 2

centimeters

(depth not to scale)

0 50 100

Cumulative percent

Core 72

Bottom of core at 0.5

centimeters

(depth not to scale)

Figure 11. Comparison of grain-size distribution (as it relates to results from bed-sediment accumulation surveys done by the U.S. 

Army Corps of Engineers in 1995 and 2008) in bed-sediment cores collected near the confluence of the Snake and Clearwater Rivers at 

A, cross-section 17, B, cross-section 18, and C, cross-section 24, eastern Washington and northern Idaho, 2010.—Continued
22 Grain-Size Distribution and Selected Major and Trace Element Concentrations in Bed-Sediment Cores

The cores collected at sites 70 and 71 were collected 

from a thick sediment deposit along cross-section 17 just 

downstream from the confluence. Following the bed-sediment 

survey in 1995, floods with peak discharges of more than 

80,000 ft3/s occurred in both 1996 and 1997 on the Clearwater 

River. Streamflow records from U.S. Geological Survey 

streamflow-gaging station 13342500 Clearwater River at 

Spalding, Idaho, document peak streamflows of more than 

85,000 ft3/s during 1996 and 1997 (U.S. Geological Survey, 

2011); this gaging station is about 16 miles upstream from 

the confluence of the Snake and Clearwater Rivers (fig. 1). 

The large peak streamflows likely deposited large amounts 

of sediment and substantially changed the channel geometry 

of the Clearwater River; 2008 channel-geometry surveys 

at cross-sections 17 and 24 document appreciable changes 

compared to 1995 (figs. 11A and11C, respectively). Channelgeometry surveys done at cross-section 18 on the Snake River 

upstream from the confluence with Clearwater River were 

essentially unchanged in 2008 compared to 1995 (fig. 11B). 

The core sample collected at site 71 (core 71), which was 

collected near the middle part of the sediment deposit at 

the confluence of the Clearwater River and Snake Rivers, 

consisted predominantly of silt and clay with some fine to 

very fine (0.25 to 0.0625 mm in diameter) sand, whereas the 

core sample collected at site 70 (core 70), which was collected 

closer to the margin of the sediment deposit, consisted 

predominantly of medium to fine sand (0.50 to 0.125 mm in 

diameter) (fig. 11A). Based on the results of the bed-sediment 

accumulation survey, approximately 2.6 m of bed sediment 

accumulated where core 70 was collected between 1995 and 

2008, and approximately 3.1 m of bed sediment accumulated 

at site 71 during that same period. Core shortening effects 

associated with vibracorer use likely resulted in sediment-core 

thicknesses that were approximately one-half of the measured 

sediment accumulation at these two locations. This would 

mean that core 71 penetrated to approximately the same 

bed-surface elevation that was observed in 1995, whereas 

core 70 only penetrated about one-half of the distance to the 

1995 bed surface. This may be because of the more coarsegrained material encountered in core 70 (very coarse sand 

from 1 to 2 mm in diameter) towards the bottom of the core. 

The thick sediment deposits at the confluence and on the 

Clearwater River may be flood-related deposits associated 

with large peak streamflows in 1996 and 1997 on the 

Clearwater River.

Neither of the cores collected on the Snake River just 

upstream from the confluence (cross-section 18, river mile 

139.43) contained silt and clay (fig. 11B). Both cores were 

very short (the core sample collected at site 72 was 0.5 cm 

long; the core sample collected at site 73 was 2 cm long) and 

made up predominantly of medium sand. An attempt also 

was made to collect a box core at site 74, but no core could 

be collected at this location because of minimal sediment 

accumulation at this location since the 1995 bathymetric 

survey (fig. 11B). The bottom material in the Snake River 

upstream from the confluence, in general, is composed 

predominantly of gravel, cobble, and boulders as a result of 

upstream reservoir trapping of fine-grained sediment by Hells 

Canyon Dam (fig. 1) (Parkinson and others, 2003) and the 

delivery of coarser grained materials from the Salmon River 

(King and others, 2004). As a result, scant silt and clay were 

found in the cores collected at sites 72 and 73.

All of the cores collected on the Clearwater River just 

upstream from the confluence (cross-section 24, river mile 

0.28) contain some silt- and clay-sized particles (fig. 11C). No 

grain-size analyses were performed on the top 60 cm of the 

bed-sediment sample collected at site 2 (core 2), but based on 

field notes, this interval was predominantly fine to medium 

sand with lenses of woody debris and clay. Cores 2 and 3 

contained an interval with a high percentage of silt and clay at 

approximately the same depth. Based on the core descriptions 

in the field notes, an interval in core 2 from 76 to 99 cm was 

classified as clay (the interval from 80 to 83 cm in this core 

was analyzed for grain size). An interval in the bed-sediment 

sample collected at site 3 (core 3) from 56 to 87 cm was 

classified as silt and clay (the interval from 62 to 65 cm in 

this core was analyzed for grain size). Based on bathymetric 

survey images (fig. 2) (Williams and others, 2012), it appears 

as though these silt and clay deposits may be flood-related 

deposits associated with large peak streamflows in 1996 and 

1997 on the Clearwater River.

Major and Trace Element 

Concentrations

Of the 69 cores collected, 50 subsamples from 15 cores 

were analyzed for major and trace elements (appendix 3). 

Concentrations of trace elements were low, with respect 

to sediment-quality guidelines (SQGs), in most cores. 

There are typically two SQGs—a lower level, below which 

adverse effects to aquatic biota are not expected, and a 

higher level, above which adverse effects are expected to 

occur. The threshold effect concentration (TEC), or lower 

level, and probable effect concentration (PEC), or higher 

level (MacDonald and others, 2000), were used to evaluate 

the concentrations of trace elements in the cores. Of the 

trace elements with TECs (arsenic, cadmium, chromium, 

copper, mercury, nickel, lead, and zinc), concentrations 

were greater than TECs in 43 percent of the analyses in the 

core sample collected at site 31 from the reservoir and 29 

percent of the analyses in the core sample collected at site 9 

from the Clearwater River (fig. 12). Chromium and copper 

concentrations most frequently exceeded the respective 

TECs. Two concentrations, 740 μg/g of copper in the bedsediment sample collected at site 9 (core 9) at 34 to 37 cm and 

2.32 μg/g of mercury in the bed-sediment sample collected at 

site 81 (core 81) at 0 to 3 cm, exceeded their respective PECs 

(150 μg/g for copper and 1.1 μg/g for mercury). The outlier 

trace element concentrations that were greater than the PECs 

were verified by the analytical laboratory (LaDonna Choate, 

U.S. Geological Survey, National Water Quality Laboratory, 

written commun., May 10, 2011). 
20406080

100120140160180

0

20406080

100120140160180

0

Depth, in centimeters Depth, in centimeters 40,000 65,000 90,000 0 30 60 0 40 80 10,000 40,000 70,000 300 

0 0.1 0.2 0.3 0 10 20 30 2,000 5,500 9,000 0 5 10 15 20 25

Aluminum, in

micrograms per gram

Chromium, in

micrograms per gram

Copper, in

micrograms per gram

mic

Iron, in

micrograms per gram

Mercury, in

micrograms per gram

Nickel, in

micrograms per gram

Titanium, in

micrograms per gram

Arsenic, in

micrograms per gram

( 740)

EXPL

T C L    C  S  

Figure 12. Concentrations of selected major and trace elements with depth (where a depth of 0 centimeters is the top of the core) in selected bed-s

Lower Granite Reservoir, the Snake and Clearwater Rivers, and the confluence of the Snake and Clearwater Rivers, eastern Washington and northern 
24 Grain-Size Distribution and Selected Major and Trace Element Concentrations in Bed-Sediment Cores

Major and trace element concentrations varied 

substantially at different coring locations and with depth in 

a single core (fig. 12). Typically, concentrations were lower 

in the samples collected from the Snake River compared to 

those collected from the Clearwater River, the confluence of 

the Snake and Clearwater Rivers, or Lower Granite Reservoir. 

Large variations in grain size occurred with depth in the 

sediment cores. The percentage of silt and clay-sized particles 

varied from 0.2 to 96.1 percent in the cores that were analyzed 

for major and trace elements. Because of the large grain-size 

variability, it is not possible to describe patterns in major and 

trace element concentrations with depth in the cores. 

Major elements in sediment generally indicate the 

minerals present. For example, high aluminum and iron 

concentrations are typically associated with clay minerals 

that, because of their finer grain size, can preferentially 

sorb trace elements (Horowitz and Elrick, 1987). All of the 

samples in the cores, except core 31, that were analyzed for 

major and trace elements were also analyzed for grain size. 

Generally, lower concentrations of major and trace elements 

were associated with coarser sediments (larger than 0.0625 

mm in diameter) and higher concentrations of major and 

trace elements were associated with finer sediments (smaller 

than 0.0625 mm in diameter) (fig. 13). Samples from the 

Clearwater River and Lower Granite Reservoir typically 

had the largest percentage of fine-grained sediments and the 

highest major and trace element concentrations. Conversely, 

the samples from the Snake River upstream from the 

confluence typically had the smallest percentage of finegrained sediments and the lowest major and trace element 

concentrations. 
2,000 3,000 4,000 5,000 6,000 7,000 8,000

10,000 20,000 30,000 40,000 50,000 60,000 70,00040,000 50,000 60,000 70,000 80,000 90,000

10 15 22 25 30

400 600 800 1,000 1,200 0 0.1 0.2 

0 2 4 6 8 

20 30 40 50 60 0 20 40 60 

0

20406080

100

0

20406080

100

0

20406080

100

Aluminum, in micrograms per gram

Iron, in micrograms per gram

Nickel, in micrograms per gram

Chromum, in micrograms per gram

Manganese, in micrograms per gram

Titanium, in micrograms per gram

Copper, in micrograms per gram

Mercury, in micrograms per gram

Arsenic, in micrograms per gram

Silt and clay smaller than 0.0625

millimeters in diameter, in percent

Silt and clay smaller than 0.0625

millimeters in diameter, in percent

Silt and clay smaller than 0.0625

millimeters in diameter, in percent

Figure 13. Comparison of percent silt and clay to selected major and trace element concentrations from bed-sediment core samples collected in Lo

Snake and Clearwater Rivers, and the confluence of the Snake and Clearwater Rivers, eastern Washington and northern Idaho, 2010. 
26 Grain-Size Distribution and Selected Major and Trace Element Concentrations in Bed-Sediment Cores

Summary

Lower Granite Reservoir is immediately downstream 

from the confluence of the Snake and Clearwater Rivers 

in eastern Washington and northern Idaho. According to 

U.S. Army Corps of Engineers (USACE), 2.6 million cubic 

yards (2.0 million cubic meters) of sediment have been 

deposited annually into Lower Granite Reservoir since its 

impoundment in 1975. Historically, the USACE dredged 

sediment to keep navigation channels clear and to maintain 

the flow capacity because increases in reservoir stage near the 

confluence reduce the effectiveness of the levees protecting 

the cities of Clarkston, Wash., and Lewiston, Idaho, against 

flooding. However, in recent years, other Federal agencies, 

Native American governments, and special interest groups 

have questioned the negative effects that dredging might 

have on threatened or endangered species. To help address 

these concerns, the U.S. Geological Survey (USGS), in 

cooperation with the USACE, collected bed-sediment core 

samples upstream from the Lower Granite Dam in the Lower 

Granite Reservoir and Snake and Clearwater Rivers. A total 

of 69 bed-sediment cores were collected at 67 locations in 

the study area, which includes Lower Granite Reservoir, the 

Snake and Clearwater Rivers, and the confluence of these 

two rivers, using one or more of the following corers: piston, 

gravity, vibrating (also called a vibracore), or box. From 

these 69 cores, 185 subsamples were removed and submitted 

for grain size analyses, 50 of which were surficial-sediment 

subsamples. A total of 50 subsamples were also submitted 

for major and trace element analyses. The multiyear project 

included surveys of the sedimentary structures (bedforms) 

of Lower Granite Reservoir using different methods. This 

report describes the results of a bed-sediment core samples 

(hereinafter cores) collected by the USGS in cooperation with 

the USACE during the spring and fall of 2010. A multibeam 

echosounding (MBES) bathymetric survey during fall 2009 

and winter 2010 and an underwater video map (UVM) survey 

of sediment facies during fall 2009 and winter 2010, also part 

of the multiyear study, are briefly described and referred to in 

the context of core sample analyses, and used to help interpret 

surficial sedimentary structures (bedforms) in the study area. 

The grain-size distribution of surficial-sediment subsamples 

from cores collected underwater in Lower Granite Reservoir, 

the Snake and Clearwater Rivers, and the confluence of these 

two rivers are described, along with the down-core grainsize distribution in cores collected at or near the confluence 

of the Snake and Clearwater Rivers. In addition, grain-size 

analyses of cores are used to provide a quantitative mechanism 

for verifying the facies map generated from previous UVM 

surveys. Percent silt and clay in surficial sediment samples 

collected from sites at the lower end of the reservoir near the 

dam, where stream velocities are lower, tended to have the 

largest proportions (more than 80 percent) of silt and clay. 

Conversely, all of the surficial sediment samples collected 

in the Snake River upstream from the confluence had less 

than 20 percent silt and clay, probably a result of velocities in 

the Snake River high enough to keep fine-grained sediment 

particles entrained. Most of the surficial sediment samples 

collected in the Clearwater River (9 out of 13) contained less 

than 40 percent silt and clay. Only one site had more than 

60 percent silt and clay, and this site was located in a nearshore, lower-velocity margin environment. Surficial sediment 

samples collected near midchannel at the confluence tended 

to have more silt and clay than most surficial sediment sample 

collection sites on the Snake and Clearwater Rivers or even 

sites further downstream in Lower Granite Reservoir. The 

turbulence and reduction in velocity induced by the confluence 

of the Snake and Clearwater Rivers likely caused these two 

rivers to drop much of their sediment load in this area.

Two core samples collected at the confluence 

were extracted from a thick sediment deposit that likely 

accumulated predominantly between 1995 and 1997; large 

peak streamflows occurred on the Clearwater River in both 

1996 and 1997. The core collected near the middle of this 

sediment deposit consisted predominantly of silt and clay with 

some fine to very fine sand, whereas the core collected closer 

to the margin of this sediment deposit consisted predominantly 

of fine to medium sand. Cores collected on the Clearwater 

River just upstream from the confluence included intervals 

with a high percentage of silt and clay at approximately the 

same depths. Based on the cross section generated from the 

bathymetric surveys, it appears as though these silt and clay 

deposits may be flood-related deposits associated with large 

peak streamflows in 1996 and 1997 on the Clearwater River. 

Both of the cores collected on the Snake River just upstream 

from the confluence were 2 cm or less in length and neither 

contained silt or clay.

Fifty samples from 15 cores were analyzed for major 

and trace elements. Concentrations of trace elements in 

most of the cores were low with respect to sediment-quality 

guidelines. Concentrations were greater than threshold 

effect concentrations in 43 percent of the analyses in core 31 

collected from the reservoir and 29 percent of the analyses 

in core 9 collected from the Clearwater River. Copper and 

chromium concentrations most frequently exceeded their 

threshold effect concentrations. Typically, major and trace 

element concentrations were lower in the samples collected 

from the Snake River upstream from the confluence as 

compared to those collected from the Clearwater River, the 

confluence of the Snake and Clearwater Rivers, and Lower 

Granite Reservoir. Large variations in grain size occurred with 

depth in the sediment cores. The percent of silt and clay-sized 

particles (smaller than 0.0625 millimeter [mm] in diameter) 

varied from 0.2 to 96.1 percent in the cores analyzed for major 

and trace elements. Because of the large grain size variability, 

it is not possible to describe trends with depth in the cores. 

Generally, lower concentrations of major and trace elements 

were associated with coarser sediments (larger than 0.0625 

mm in diameter) and higher concentrations of major and trace 

elements were associated with finer sediments (smaller than 

0.0625 mm in diameter). Samples from the Clearwater River 
References Cited 27

and Lower Granite Reservoir typically had higher proportions 

of fine-grained sediments and higher concentrations of major 

and trace elements as compared to samples collected from the 

Snake River upstream from the confluence. 

References Cited

Briggs, P.H., and Meier, A.L., 2002, The determination of 

forty-two elements in geological materials by inductively 

coupled plasma-mass spectrometry for NAWQA, in

Taggart, J.E., Jr., ed., Analytical methods for chemical 

analysis of geologic and other materials: U.S. Geological 

Survey Open-File Report 02–223–J, p. J1–J14. (Also 

available at http://pubs.usgs.gov/of/2002/ofr-02-0223/

J22NAWQAMethod_M.pdf.)

Emery, K.O., and Hulsemann, J., 1964, Shortening of 

sediment cores collected in open barrel gravity corers: 

Sedimentology, v. 3, p. 144–154.

Fan, Jiahua, and Morris, G.L., 1992, Reservoir 

sedimentation—Delta and density current deposits: Journal 

of Hydraulic Engineering, v. 118, no. 3, p. 354–369.

Germanoski, D., and Schumm, S.A., 1993, Changes in 

braided river morphology resulting from aggradation and 

degradation: The Journal of Geology, v. 101, no. 4, 

p. 451–466.

Guy, H.P., 1969, Laboratory theory and methods for sediment 

analysis: U.S. Geological Survey Techniques of WaterResources Investigations, chap. Cl, book 5, 58 p. 

Hageman, P.L., 2007, Determination of mercury in aqueous 

and geologic materials by continuous flow-cold vaporatomic fluorescence spectrometry (CVAFS): U.S. 

Geological Survey Techniques and Methods, book 5, 

chap. D2, 6 p.

Horowitz, A.J., and Elrick, K.A., 1987, The relation of stream 

sediment surface area, grain size and composition to trace 

element chemistry: Applied Geochemistry, v. 2, p. 437–451.

Juracek, K.E., 1998, Analysis of lake-bottom sediment to 

estimate historical nonpoint-source phosphorous loads: 

Journal of the American Water Resources Association, v. 34, 

no. 6, p. 1449–1463.

King, J.G., Emmett, W.W., Whiting, P.J., Kenworthy, R.P., 

and Barry, J.J., 2004, Sediment transport data and related 

information for selected coarse-bed streams and rivers 

in Idaho: U.S. Department of Agriculture Forest Service, 

Rocky Mountain Research Station General Technical 

Report RMRS–GTR–131, 26 p., accessed July 9, 2012, 

at http://www.fs.fed.us/rm/boise/publications/watershed/

rmrs_gtr131.pdf.

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

Development and evaluation of consensus-based sediment 

quality guidelines for freshwater ecosystems: Archives 

of Environmental Contamination and Toxicology, v. 39, 

p. 20–31.

Meyer, A., and Fisher, A., 1997, Data report: Grain-size 

analysis of sediments from the northern Barbados 

accretionary prism, in Shipley, T.H., Ogawa, Y., Blum, P., 

and Bahr, J.M., eds., Proceedings of the Ocean Drilling 

Program, Scientific Results, College Station, Tex., Ocean 

Drilling Program, p. 337–341.

National Agriculture Imagery Program, 2009, 1-Meter 

compressed county mosaic map: U.S. Department of 

Agriculture Farm Service Agency, Aerial Photography Field 

Office, scale 1:3,780.

National Institute of Standards and Technology, 2003a, 

Certificate of analysis, standard reference material 2709, 

San Joaquin soil—Baseline trace element concentrations: 

National Institute of Standards and Technology, accessed 

February 3, 2011, at https://www-s.nist.gov/srmors/

certificates/2709.pdf.

National Institute of Standards and Technology, 2003b, 

Certificate of analysis, standard reference material 

2711, Montana soil—Moderately elevated trace element 

concentrations: National Institute of Standards and 

Technology, accessed June 15, 2011, at https://www-s.nist.

gov/srmors/certificates/view_certPDF.cfm?certificate=2711.

National Institute of Standards and Technology, 2008, Report 

of investigation, reference material 8704, Buffalo River 

sediment: National Institute of Standards and Technology, 

accessed February 3, 2011, at https://www-s.nist.gov/

srmors/reports/8704.pdf.

Parkinson, S., Anderson, K., Conner, J., and Milligan J., 2003, 

Sediment transport, supply and stability in the Hells Canyon 

Reach of the Snake River: Idaho Power Technical Report 

for FERC No. 1971, 140 p.

Pirkey, K.D., and Glodt, S.R., 1998, Quality control at the 

U.S. Geological Survey National Water Quality Laboratory: 

U.S. Geological Survey Fact Sheet FS–026–98, 4 p.

Pope, L.R., and Ward, C.W., eds., 1998, Manual on test 

sieving methods—Guidelines for establishing sieve analysis 

procedures (4th ed.): West Conshohocken, Pa., American 

Society for Testing and Materials, 43 p.

Potts, P.J., Tindle, A.G., and Webb, P.C., 1992, Geochemical 

reference material compositions—Rocks, minerals, 

sediments, soils, carbonates, refractories, and ores used 

in research and industry: Boca Raton, Fla., CRC Press, 

313 p.
28 Grain-Size Distribution and Selected Major and Trace Element Concentrations in Bed-Sediment Cores

Shelton, L.R., 1994, Guidelines for collecting and processing 

samples of bed sediment for analysis of trace elements 

and organic contaminants for the National Water Quality 

Assessment Program: U.S. Geological Survey Open-File 

Report 94–458, 20 p.

Taggart, J.E., Jr., ed., 2002, Analytical methods for chemical 

analysis of geologic and other materials: U.S. Geological 

Survey Open-File Report 02–223 [variously paged].

U.S. Army Corps of Engineers, 2002, Lower Snake River 

juvenile salmon migration feasibility report/environmental 

impact statement—Appendix T: US Army Corps of 

Engineers, Walla Walla District, accessed September 19, 

2012, at http://www.nww.usace.army.mil/portals/28/docs/

environmental/lsrstudy/Appendix_T.pdf.

U.S. Army Corps of Engineers, 2003, Supplemental 

environmental analysis for the purposes of 2003-2004 

dredging (Lower Snake and Clearwater Rivers, Washington 

and Idaho): U.S. Army Corps of Engineers, Walla Walla 

District, Washington.

U.S. Army Corps of Engineers, 2004, Framework for 

assessment of potential effects of dredging on sensitive 

fish species in San Francisco Bay: U.S. Army Corps of 

Engineers Final Report, August 5, 2004, 001-09170-00, San 

Francisco District, California.

U.S. Geological Survey, 2011, USGS water data for Idaho: 

National Water Information System: Web interface, 

accessed on September 14, 2011, at http://waterdata.usgs.

gov/id/nwis.

Van Metre, P.C., Wilson, J.T., Fuller, C.C., Callender, Edward, 

and Mahler, B.J., 2004, Collection, analysis, and agedating of sediment cores from 56 U.S. lakes and reservoirs 

sampled by the U.S. Geological Survey, 1992–2001: U.S. 

Geological Survey Scientific Investigations Report 2004–

5184, 180 p.

Vibracoring Concepts, 2011, Core sampling basics, in 

Vibracoring a practical guide: Vibracoring Concepts, 

accessed on February 15, 2011, at http://www.vibracoring.

com/VCconcepts.html.

Wentworth, C.K., 1922, A scale of grade and class terms 

for clastic sediments: The Journal of Geology, v. 30, 

p. 377–392.

Williams, M.L., Fosness, R.L., and Weakland, R.J., 2012, 

Bathymetric and underwater video survey of Lower Granite 

Reservoir and vicinity, Washington and Idaho, 2009–10: 

U.S. Geological Survey Scientific Investigations Report 

2012–5089, 22 p.
Appendix 1—Distance from Bank and Elevation Data for Cross 

Sections 17, 18, and 24

Appendix 1
30 Grain-Size Distribution and Selected Major and Trace Element Concentrations in Bed-Sediment Cores

Appendix 1. Distance from bank and elevation data for cross sections 17, 18, and 24 measured near the confluence of the Clearwater 

and Snake Rivers in eastern Washington and and northern Idaho, 1995 and 2008.—Continued

[dist., distance; left bank, as viewed by looking downstream; m, meters; elevation above the North American Vertical Datum of 1988; NA, not applicable; 1995 

data were digitized from cross sections measured by the U.S. Army Corps of Engineers during 1995; 2008 data were from cross sections measured during 2008; 

data provided by the U.S. Army Corps of Engineers [Gregg Teasdale, U.S. Army Corps of Engineers, written commun., 2010])

Cross section 17 Cross section 18 Cross section 24

1995 2008 1995 2008 1995 2008

Dist. from 

left bank 

(m)

Elevation 

(m)

Dist. from 

left bank 

(m)

Elevation 

(m)

Dist. from 

left bank 

(m)

Elevation 

(m)

Dist. from 

left bank 

(m)

Elevation 

(m)

Dist. from 

left bank 

(m)

Elevation 

(m)

Dist. from 

left bank 

(m)

Elevation 

(m)

22.2 221.819 17.3 222.332 34.2 222.627 35.1 222.452 15.6 219.902 15.1 220.456

25.6 221.471 17.3 222.277 34.2 222.151 35.1 222.324 16.9 219.210 15.1 220.456

26.8 221.415 18.3 222.228 38.2 221.200 35.1 222.059 17.9 218.400 16.9 219.999

30.4 221.200 18.3 222.171 40.9 220.808 35.1 221.693 18.9 217.258 18.8 219.755

30.9 221.083 19.5 222.100 42.0 220.728 39.3 221.327 23.5 216.480 18.8 219.755

32.4 220.871 20.8 221.975 42.7 220.725 39.3 220.961 24.9 216.100 20.9 219.450

36.8 220.700 22.3 221.854 44.2 220.522 41.6 220.715 25.7 215.854 23.1 219.054

40.0 220.500 23.9 221.762 46.0 220.222 41.6 220.471 27.0 215.805 23.1 219.054

45.6 220.090 25.7 221.637 48.2 220.034 43.9 220.288 27.8 215.805 25.3 218.688

48.4 219.183 25.7 221.515 49.2 219.852 43.9 220.105 29.5 215.711 25.3 218.688

49.8 218.861 27.6 221.393 49.3 219.709 46.3 220.041 30.4 215.606 27.6 218.383

52.5 218.400 29.6 221.241 50.5 219.376 46.3 219.889 32.5 215.222 29.9 218.139

54.2 218.330 29.6 221.116 52.6 218.663 48.8 219.706 32.9 215.100 29.9 218.139

66.6 217.121 31.7 221.055 53.4 218.400 48.8 219.553 35.0 215.019 32.3 217.865

70.3 217.004 33.8 220.964 54.9 217.600 51.4 219.218 37.4 214.794 32.3 217.865

70.6 216.789 33.8 220.903 55.4 217.300 51.4 218.913 40.6 214.628 34.6 217.865

76.4 216.539 36.0 220.781 55.6 217.176 54.0 218.547 42.6 214.562 34.6 217.865

78.9 216.829 36.0 220.686 56.8 216.753 54.0 218.212 44.3 214.539 37.0 217.743

81.3 216.856 38.2 220.564 58.2 216.000 56.5 217.813 45.3 214.546 39.4 217.621

83.9 216.533 40.4 220.442 61.5 215.520 56.5 217.356 47.6 214.669 39.4 217.621

86.7 216.340 40.4 220.287 68.3 214.800 59.1 216.716 48.5 214.686 41.8 217.591

90.0 216.238 42.7 220.074 72.5 214.200 61.7 216.350 49.4 214.712 41.8 217.591

93.3 215.691 42.7 219.860 73.5 214.008 61.7 215.981 53.8 214.948 44.3 217.499

97.1 215.595 45.0 219.555 74.8 213.832 64.3 215.737 54.1 214.959 46.8 217.499

97.5 215.470 47.3 219.129 75.9 213.720 64.3 215.524 56.4 215.111 46.8 217.499

99.1 215.341 47.3 218.821 77.5 213.616 66.9 215.310 59.6 215.381 49.2 217.499

105.5 214.953 49.6 218.607 79.0 213.582 66.9 215.036 61.7 215.504 51.7 217.530

108.8 214.948 49.6 218.333 80.4 213.493 69.4 214.850 64.2 215.591 51.7 217.530

109.7 214.981 52.0 218.059 85.7 213.316 69.4 214.667 65.9 215.680 54.2 217.652

112.0 214.975 54.4 217.876 86.8 213.293 71.9 214.515 67.0 215.716 54.2 217.652

118.8 214.779 54.4 217.724 95.1 213.302 71.9 214.362 68.0 215.721 56.7 217.743

122.5 214.771 56.8 217.632 97.9 213.141 74.5 214.149 68.6 215.711 59.2 217.774

123.7 214.813 56.8 217.477 99.3 213.133 74.5 213.783 70.1 215.711 59.2 217.774

125.7 214.809 59.3 217.294 100.9 213.055 77.1 213.661 71.2 215.749 61.7 217.865

130.8 214.660 59.3 217.172 107.0 212.700 77.1 213.722 72.9 215.733 61.7 217.865

Appendix 1. Distance from bank and elevation data for cross sections 17, 18, and 24 measured near the confluence of the Clearwater 

and Snake Rivers in eastern Washington and and northern Idaho, 1995 and 2008.

[dist., distance; left bank, as viewed by looking downstream; m, meters; elevation above the North American Vertical Datum of 1988; NA, not applicable; 1995 

data were digitized from cross sections measured by the U.S. Army Corps of Engineers during 1995; 2008 data were from cross sections measured during 2008; 

data provided by the U.S. Army Corps of Engineers [Gregg Teasdale, U.S. Army Corps of Engineers, written commun., 2010])
Appendix 1 31

Appendix 1. Distance from bank and elevation data for cross sections 17, 18, and 24 measured near the confluence of the Clearwater 

and Snake Rivers in eastern Washington and and northern Idaho, 1995 and 2008.—Continued

[dist., distance; left bank, as viewed by looking downstream; m, meters; elevation above the North American Vertical Datum of 1988; NA, not applicable; 1995 

data were digitized from cross sections measured by the U.S. Army Corps of Engineers during 1995; 2008 data were from cross sections measured during 2008; 

data provided by the U.S. Army Corps of Engineers [Gregg Teasdale, U.S. Army Corps of Engineers, written commun., 2010])

Cross section 17 Cross section 18 Cross section 24

1995 2008 1995 2008 1995 2008

Dist. from 

left bank 

(m)

Elevation 

(m)

Dist. from 

left bank 

(m)

Elevation 

(m)

Dist. from 

left bank 

(m)

Elevation 

(m)

Dist. from 

left bank 

(m)

Elevation 

(m)

Dist. from 

left bank 

(m)

Elevation 

(m)

Dist. from 

left bank 

(m)

Elevation 

(m)

133.4 214.619 61.7 217.050 109.6 212.389 79.7 213.661 74.0 215.706 64.2 217.926

140.3 214.619 64.2 216.958 113.3 212.114 82.3 213.201 75.0 215.717 66.7 218.017

142.2 214.583 64.2 216.898 114.4 211.980 82.3 213.140 76.9 215.840 66.7 218.017

144.5 214.659 66.7 216.837 117.3 211.436 84.9 213.110 78.2 215.874 69.1 218.109

148.9 214.537 69.1 216.715 118.7 211.366 84.9 213.049 79.5 215.904 69.1 218.109

151.6 214.616 69.1 216.623 122.3 211.288 87.6 212.988 80.6 215.904 71.6 218.078

156.0 214.340 71.6 216.471 123.1 211.288 90.3 212.896 81.2 215.878 74.1 217.956

160.3 214.440 71.6 216.349 124.8 211.352 90.3 212.835 82.1 215.883 74.1 217.956

176.9 212.911 74.1 216.318 127.3 211.348 92.8 212.741 83.3 215.904 76.6 218.170

178.1 212.773 74.1 216.227 130.0 211.463 95.3 212.619 85.0 215.971 79.0 218.200

185.0 213.148 76.6 216.166 132.5 211.544 95.3 212.558 86.4 216.048 79.0 218.200

193.2 213.914 79.0 216.075 135.3 211.964 97.8 212.436 87.3 216.059 81.5 218.170

198.8 214.042 79.0 215.953 138.2 212.033 97.8 212.345 90.3 216.075 81.5 218.170

200.5 214.159 81.5 215.861 142.4 212.038 100.3 212.284 91.9 216.091 84.0 218.200

202.5 214.151 83.9 215.831 144.8 211.978 100.3 212.192 96.7 216.279 86.4 218.292

202.9 214.074 83.9 215.770 147.4 211.980 102.8 212.162 99.2 216.284 86.4 218.292

205.0 214.081 86.4 215.648 150.4 212.307 105.3 212.101 100.0 216.330 88.9 218.292

210.4 214.253 86.4 215.556 153.1 212.301 105.3 212.070 101.9 216.564 91.4 218.292

217.6 214.081 88.9 215.465 160.8 212.932 107.8 212.040 103.8 216.883 91.4 218.292

221.4 214.081 88.9 215.374 163.1 213.078 107.8 212.009 110.9 217.461 93.8 218.353

223.2 214.102 91.3 215.282 163.8 213.157 110.3 212.101 114.4 217.562 93.8 218.353

226.1 214.061 91.3 215.221 165.8 213.292 110.3 212.101 116.5 217.562 96.3 218.353

226.9 214.000 93.8 215.069 167.5 213.369 112.8 212.040 116.7 217.483 98.7 218.292

231.2 214.010 93.8 214.886 170.4 213.378 115.2 211.948 117.7 217.239 98.7 218.292

238.4 213.761 96.2 214.886 170.6 213.414 115.2 211.888 118.5 216.931 101.2 218.475

241.6 213.756 96.2 214.825 172.5 213.500 117.7 211.827 120.8 216.868 101.2 218.475

244.6 213.609 98.7 214.733 176.4 213.707 117.7 211.766 122.7 216.776 103.6 218.536

245.9 213.454 98.7 214.703 178.0 213.739 120.2 211.644 123.7 216.707 106.1 218.566

251.7 213.441 101.1 214.612 180.8 213.773 122.6 211.583 126.5 216.707 106.1 218.566

257.0 213.868 103.5 214.581 183.5 213.867 122.6 211.552 128.4 216.648 108.5 218.627

260.5 214.230 103.5 214.551 185.1 213.901 125.1 211.552 130.4 216.685 108.5 218.627

261.7 214.730 106.0 214.672 187.6 213.899 125.1 211.522 131.7 216.700 111.0 218.657

264.7 215.300 108.4 214.733 190.6 213.838 127.6 211.461 133.7 216.700 111.0 218.657

267.8 215.141 108.4 214.733 192.0 213.822 130.1 211.552 135.4 216.777 113.4 218.596

272.1 215.059 110.8 214.672 193.7 213.850 130.1 211.613 136.1 216.787 115.9 218.627
32 Grain-Size Distribution and Selected Major and Trace Element Concentrations in Bed-Sediment Cores

Appendix 1. Distance from bank and elevation data for cross sections 17, 18, and 24 measured near the confluence of the Clearwater 

and Snake Rivers in eastern Washington and and northern Idaho, 1995 and 2008.—Continued

[dist., distance; left bank, as viewed by looking downstream; m, meters; elevation above the North American Vertical Datum of 1988; NA, not applicable; 1995 

data were digitized from cross sections measured by the U.S. Army Corps of Engineers during 1995; 2008 data were from cross sections measured during 2008; 

data provided by the U.S. Army Corps of Engineers [Gregg Teasdale, U.S. Army Corps of Engineers, written commun., 2010])

Cross section 17 Cross section 18 Cross section 24

1995 2008 1995 2008 1995 2008

Dist. from 

left bank 

(m)

Elevation 

(m)

Dist. from 

left bank 

(m)

Elevation 

(m)

Dist. from 

left bank 

(m)

Elevation 

(m)

Dist. from 

left bank 

(m)

Elevation 

(m)

Dist. from 

left bank 

(m)

Elevation 

(m)

Dist. from 

left bank 

(m)

Elevation 

(m)

275.9 215.051 110.8 214.551 196.1 213.939 132.6 211.647 137.7 216.787 115.9 218.627

277.2 215.500 115.6 214.429 198.2 214.037 135.1 211.677 138.4 216.777 118.4 218.657

280.3 216.371 115.6 214.337 199.9 214.045 135.1 211.677 139.5 216.780 118.4 218.657

285.1 215.487 115.6 214.218 201.3 214.092 137.6 211.769 141.0 216.797 120.8 218.627

289.3 215.414 118.0 214.127 202.9 214.249 137.6 211.830 143.6 216.776 120.8 218.627

290.9 215.114 118.0 214.035 204.8 214.341 140.1 211.921 147.9 216.809 123.3 218.657

303.9 214.702 120.4 214.005 205.8 214.372 142.7 211.982 150.4 216.819 125.8 218.657

308.4 214.841 122.8 213.914 208.8 214.534 142.7 212.043 152.3 216.781 125.8 218.657

310.0 215.041 122.8 213.822 216.1 214.821 145.2 212.073 153.7 216.728 128.3 218.779

310.6 215.181 125.3 213.761 217.7 215.028 145.2 212.101 154.6 216.718 128.3 218.779

313.6 215.341 127.7 213.667 218.5 215.094 147.7 212.131 158.2 216.707 130.7 218.688

319.4 214.758 127.7 213.667 219.1 215.231 147.7 212.314 160.3 216.562 130.7 218.688

322.3 214.692 130.2 213.697 221.9 215.331 150.2 212.375 161.6 216.562 133.2 218.779

323.8 214.969 130.2 213.728 222.3 215.420 152.7 212.467 164.0 216.589 135.7 218.871

326.3 215.231 132.7 213.728 224.1 215.628 152.7 212.558 166.3 216.599 135.7 218.871

329.0 215.295 135.0 213.757 227.9 215.845 155.2 212.619 168.4 216.648 138.2 218.962

331.0 215.295 135.0 213.787 231.2 216.119 155.2 212.710 171.5 216.652 138.2 218.962

333.3 215.253 137.4 213.726 232.0 216.147 157.7 212.802 175.0 216.672 140.6 218.901

336.9 215.253 137.4 213.604 233.9 216.518 157.7 212.893 177.2 216.690 140.6 218.901

345.4 215.399 139.8 213.513 237.5 217.081 160.2 213.015 179.3 216.620 143.1 218.718

347.9 215.351 142.1 213.422 239.5 217.755 160.2 213.107 180.4 216.510 143.1 218.718

351.2 215.454 142.1 213.361 242.1 217.913 162.7 213.198 183.7 216.561 145.5 218.779

354.4 215.429 144.5 213.300 243.4 217.948 165.2 213.320 185.2 216.582 148.0 218.779

355.4 215.697 144.5 213.208 246.3 217.956 165.2 213.351 187.2 216.545 150.5 218.810

358.7 215.611 146.9 213.147 247.8 218.020 167.7 213.442 188.2 216.530 150.5 218.810

371.6 215.989 146.9 213.086 250.0 218.330 167.7 213.472 192.5 216.530 153.0 218.840

375.2 215.930 149.2 213.056 252.3 218.532 170.2 213.533 194.2 216.498 153.0 218.840

377.4 215.989 151.6 212.995 254.0 218.583 172.7 213.503 195.3 216.481 155.4 218.871

380.4 215.989 151.6 212.873 255.7 218.620 172.7 213.533 196.8 216.514 155.4 218.871

386.5 216.223 153.9 212.781 257.2 218.628 175.2 213.747 199.0 216.529 157.9 218.871

392.7 216.243 153.9 212.751 259.0 218.583 175.2 213.686 202.1 216.546 160.4 218.901

393.3 216.326 156.2 212.721 260.6 218.563 177.7 213.744 204.6 216.535 160.4 218.901

398.5 216.243 158.6 212.660 262.5 218.557 180.3 213.744 208.7 216.557 162.9 218.962

405.3 216.410 158.6 212.446 264.5 218.479 180.3 213.805 211.4 216.529 162.9 218.962

406.6 216.485 160.9 212.355 268.6 218.471 182.8 213.896 212.9 216.487 165.4 218.901
Appendix 1 33

Appendix 1. Distance from bank and elevation data for cross sections 17, 18, and 24 measured near the confluence of the Clearwater 

and Snake Rivers in eastern Washington and and northern Idaho, 1995 and 2008.—Continued

[dist., distance; left bank, as viewed by looking downstream; m, meters; elevation above the North American Vertical Datum of 1988; NA, not applicable; 1995 

data were digitized from cross sections measured by the U.S. Army Corps of Engineers during 1995; 2008 data were from cross sections measured during 2008; 

data provided by the U.S. Army Corps of Engineers [Gregg Teasdale, U.S. Army Corps of Engineers, written commun., 2010])

Cross section 17 Cross section 18 Cross section 24

1995 2008 1995 2008 1995 2008

Dist. from 

left bank 

(m)

Elevation 

(m)

Dist. from 

left bank 

(m)

Elevation 

(m)

Dist. from 

left bank 

(m)

Elevation 

(m)

Dist. from 

left bank 

(m)

Elevation 

(m)

Dist. from 

left bank 

(m)

Elevation 

(m)

Dist. from 

left bank 

(m)

Elevation 

(m)

409.2 216.432 160.9 212.355 270.7 218.515 185.4 213.927 214.2 216.439 167.8 218.962

412.1 216.557 163.2 212.324 273.0 218.500 185.4 213.957 214.9 216.439 167.8 218.962

416.0 216.458 165.5 212.294 275.0 218.468 187.9 213.927 216.7 216.503 170.3 219.023

417.6 216.362 165.5 212.233 276.9 218.483 187.9 213.927 218.5 216.541 172.4 218.871

422.1 216.578 167.8 212.233 278.8 218.675 190.5 213.927 221.3 216.556 172.4 218.871

424.4 216.583 170.3 212.263 281.0 218.779 190.5 213.866 223.9 216.504 175.3 218.993

427.3 216.452 170.3 212.324 283.9 218.604 193.0 213.957 224.8 216.476 175.3 218.993

428.3 216.361 172.9 212.416 285.4 218.567 193.0 213.927 226.5 216.467 177.7 218.932

431.2 216.286 172.9 212.480 286.2 218.571 195.5 213.988 228.1 216.423 180.2 218.993

435.4 216.340 175.5 212.571 288.7 218.687 198.1 214.018 229.3 216.358 180.2 218.993

441.5 216.251 178.1 212.663 294.0 218.687 198.1 214.110 231.5 216.343 182.7 218.932

448.5 216.258 178.1 212.693 296.5 218.584 200.7 214.170 233.7 216.283 182.7 218.932

453.5 216.369 180.6 212.845 298.5 218.727 203.2 214.231 240.3 216.280 185.2 218.901

456.8 216.369 180.6 212.967 300.2 218.828 203.2 214.292 241.6 216.262 187.7 218.932

462.0 216.452 183.2 213.059 302.2 218.831 205.8 214.353 242.8 216.252 187.7 218.932

465.9 216.452 183.2 213.211 304.7 218.692 205.8 214.414 248.0 216.241 189.6 218.932

471.4 216.353 185.8 213.333 305.7 218.651 208.4 214.536 249.0 216.182 192.0 219.023

474.3 216.257 185.8 213.394 308.5 218.651 208.4 214.597 250.2 216.123 192.0 219.023

477.2 216.216 188.4 213.547 309.6 218.699 213.6 214.628 255.6 216.129 194.5 219.115

481.7 215.951 188.4 213.638 314.2 218.695 213.6 214.719 257.5 216.042 194.5 219.115

487.3 215.943 190.9 213.760 316.8 218.629 213.6 214.814 260.8 216.480 196.9 219.084

490.8 215.798 190.9 213.821 318.0 218.661 216.2 214.966 263.6 216.124 199.4 218.962

496.6 216.052 193.5 213.943 320.7 218.652 218.9 215.057 266.2 216.188 199.4 218.962

500.3 216.230 196.1 213.973 322.0 218.748 218.9 215.179 268.6 216.232 201.8 218.871

505.5 216.342 196.1 213.973 322.8 218.748 221.4 215.301 270.2 216.267 204.3 218.932

509.0 216.389 198.7 214.004 324.2 218.689 221.4 215.393 271.7 216.200 204.3 218.932

511.2 216.348 201.4 214.004 325.5 218.695 224.0 215.515 272.5 216.129 206.8 219.084

516.1 216.334 201.4 214.034 326.0 218.716 224.0 215.758 273.4 216.123 209.2 219.237

518.4 216.278 204.0 214.065 326.4 218.800 226.5 215.789 274.8 216.149 209.2 219.237

520.6 216.238 204.0 214.034 327.7 219.032 226.5 215.880 276.3 216.161 211.7 219.298

525.5 216.292 206.6 214.126 328.9 219.071 229.0 216.002 276.9 216.129 211.7 219.298

530.4 216.300 206.6 214.126 329.3 219.940 229.0 216.094 278.0 216.129 214.1 219.267

533.8 216.188 209.3 214.187 NA NA 231.6 216.216 280.3 216.194 214.1 219.267

538.5 216.188 209.3 214.187 NA NA 231.6 216.246 282.0 216.213 216.6 219.176

543.0 216.111 211.9 214.217 NA NA 234.2 216.460 283.9 216.230 219.1 219.054
34 Grain-Size Distribution and Selected Major and Trace Element Concentrations in Bed-Sediment Cores

Appendix 1. Distance from bank and elevation data for cross sections 17, 18, and 24 measured near the confluence of the Clearwater 

and Snake Rivers in eastern Washington and and northern Idaho, 1995 and 2008.—Continued

[dist., distance; left bank, as viewed by looking downstream; m, meters; elevation above the North American Vertical Datum of 1988; NA, not applicable; 1995 

data were digitized from cross sections measured by the U.S. Army Corps of Engineers during 1995; 2008 data were from cross sections measured during 2008; 

data provided by the U.S. Army Corps of Engineers [Gregg Teasdale, U.S. Army Corps of Engineers, written commun., 2010])

Cross section 17 Cross section 18 Cross section 24

1995 2008 1995 2008 1995 2008

Dist. from 

left bank 

(m)

Elevation 

(m)

Dist. from 

left bank 

(m)

Elevation 

(m)

Dist. from 

left bank 

(m)

Elevation 

(m)

Dist. from 

left bank 

(m)

Elevation 

(m)

Dist. from 

left bank 

(m)

Elevation 

(m)

Dist. from 

left bank 

(m)

Elevation 

(m)

548.5 216.145 214.6 214.187 NA NA 234.2 216.764 285.9 216.210 219.1 219.054

552.4 216.082 214.6 214.156 NA NA 236.7 217.069 287.3 216.161 223.9 218.962

555.6 215.944 214.6 214.126 NA NA 239.2 217.465 290.0 215.931 223.9 218.962

562.1 215.938 217.3 214.156 NA NA 239.2 217.648 291.7 215.889 226.3 218.932

566.0 215.881 219.9 214.156 NA NA 241.8 217.801 294.9 215.889 226.3 218.932

572.9 215.881 219.9 214.156 NA NA 241.8 217.743 296.3 215.844 228.7 218.901

576.7 215.805 222.5 214.095 NA NA 244.4 217.804 297.2 215.829 228.7 218.901

579.0 215.811 225.2 214.065 NA NA 247.0 217.926 299.0 215.774 231.1 218.901

581.3 215.839 225.2 214.034 NA NA 247.0 218.044 301.1 215.722 233.5 218.871

583.5 215.749 227.9 214.004 NA NA 249.6 218.166 302.2 215.708 235.0 218.718

589.2 215.728 227.9 214.004 NA NA 249.6 218.258 304.4 215.582 235.0 218.718

591.3 215.651 230.6 214.034 NA NA 252.1 218.380 306.6 215.541 237.4 218.657

595.5 215.740 230.6 214.034 NA NA 252.1 218.471 308.2 215.556 237.4 218.657

600.6 215.423 233.3 214.037 NA NA 254.6 218.532 309.9 215.582 239.9 218.596

603.3 215.330 235.9 214.068 NA NA 257.2 218.563 312.4 215.641 242.4 218.505

606.3 215.330 235.9 214.037 NA NA 257.2 218.593 314.5 215.716 242.4 218.505

609.1 215.380 238.6 214.007 NA NA 259.9 218.502 316.3 215.797 244.8 218.383

611.1 215.392 238.6 213.946 NA NA 262.5 218.471 316.9 215.846 244.8 218.383

612.1 215.545 241.3 213.854 NA NA 262.5 218.471 318.1 215.846 247.4 218.261

613.0 215.671 241.3 213.824 NA NA 265.1 218.441 319.3 215.835 247.4 218.261

615.9 215.733 243.9 213.824 NA NA 267.7 218.471 321.0 215.931 249.9 217.865

616.8 215.837 246.6 213.854 NA NA 267.7 218.410 322.6 216.007 252.4 217.713

617.9 215.902 246.6 213.748 NA NA 270.3 218.410 323.9 216.059 252.4 217.713

622.4 215.937 249.2 213.656 NA NA 272.9 218.410 325.6 216.080 254.9 217.621

630.5 216.118 249.2 213.717 NA NA 272.9 218.471 327.9 216.059 257.3 217.499

632.9 216.113 251.9 213.748 NA NA 275.6 218.529 331.0 216.006 257.3 217.499

635.7 216.053 254.6 213.778 NA NA 278.2 218.590 334.5 215.990 259.9 217.408

638.2 216.042 254.6 213.870 NA NA 278.2 218.651 339.7 215.941 259.9 217.408

642.0 215.925 257.3 213.900 NA NA 280.7 218.651 343.8 215.931 262.4 217.255

645.4 215.867 257.3 213.900 NA NA 280.7 218.590 347.8 215.931 264.9 217.316

646.7 215.811 259.9 213.839 NA NA 283.3 218.560 349.3 215.963 264.9 217.316

650.1 215.924 259.9 213.839 NA NA 285.9 218.529 351.8 216.032 267.4 217.225

654.5 215.810 262.6 213.992 NA NA 285.9 218.499 355.1 216.032 269.8 217.194

659.3 215.742 262.6 214.053 NA NA 288.5 218.590 358.2 216.589 269.8 217.194

664.8 215.602 265.3 214.174 NA NA 288.5 218.590 359.9 217.177 272.3 216.951
Appendix 1 35

Appendix 1. Distance from bank and elevation data for cross sections 17, 18, and 24 measured near the confluence of the Clearwater 

and Snake Rivers in eastern Washington and and northern Idaho, 1995 and 2008.—Continued

[dist., distance; left bank, as viewed by looking downstream; m, meters; elevation above the North American Vertical Datum of 1988; NA, not applicable; 1995 

data were digitized from cross sections measured by the U.S. Army Corps of Engineers during 1995; 2008 data were from cross sections measured during 2008; 

data provided by the U.S. Army Corps of Engineers [Gregg Teasdale, U.S. Army Corps of Engineers, written commun., 2010])

Cross section 17 Cross section 18 Cross section 24

1995 2008 1995 2008 1995 2008

Dist. from 

left bank 

(m)

Elevation 

(m)

Dist. from 

left bank 

(m)

Elevation 

(m)

Dist. from 

left bank 

(m)

Elevation 

(m)

Dist. from 

left bank 

(m)

Elevation 

(m)

Dist. from 

left bank 

(m)

Elevation 

(m)

Dist. from 

left bank 

(m)

Elevation 

(m)

665.8 215.502 265.3 214.296 NA NA 291.1 218.621 361.7 217.960 272.3 216.951

668.7 215.436 268.1 214.662 NA NA 293.6 218.560 363.0 218.360 274.8 216.951

672.3 215.461 268.1 214.936 NA NA 293.6 218.560 365.0 218.860 274.8 216.951

676.2 215.288 270.7 215.089 NA NA 296.2 218.529 367.0 219.300 277.3 216.890

681.4 215.129 270.7 215.363 NA NA 298.8 218.590 368.5 219.600 277.3 216.890

686.4 215.169 273.4 215.455 NA NA 298.8 218.682 369.7 219.954 279.8 216.676

693.4 215.280 273.4 215.607 NA NA 301.3 218.755 370.8 220.112 279.8 216.676

695.8 215.495 276.1 215.272 NA NA 301.3 218.697 NA NA 282.2 216.341

695.4 215.742 276.1 215.512 NA NA 303.9 218.666 NA NA 284.7 216.250

698.4 215.797 278.8 215.025 NA NA 303.9 218.636 NA NA 284.7 216.250

698.6 216.051 278.8 214.964 NA NA 306.4 218.636 NA NA 287.2 215.975

705.0 215.950 281.5 215.177 NA NA 308.9 218.636 NA NA 287.2 215.975

708.8 215.882 281.5 215.604 NA NA 311.4 218.636 NA NA 289.6 215.792

711.2 215.812 284.3 215.848 NA NA 311.4 218.636 NA NA 292.0 215.609

714.7 215.865 284.3 216.214 NA NA 313.9 218.639 NA NA 292.0 215.609

718.3 216.051 287.0 216.274 NA NA 316.2 218.608 NA NA 294.4 215.457

721.4 216.284 287.0 216.122 NA NA 316.2 218.547 NA NA 296.8 215.274

726.4 217.900 289.7 215.970 NA NA 318.4 218.608 NA NA 296.8 215.274

730.6 219.318 289.7 215.787 NA NA 320.4 218.669 NA NA 299.2 215.183

730.6 219.577 292.4 215.573 NA NA 322.3 218.642 NA NA 299.2 215.183

734.2 220.089 292.4 215.540 NA NA 324.1 218.672 NA NA 301.6 215.061

737.4 220.952 295.2 215.357 NA NA 325.7 219.160 NA NA 304.0 214.939

NA NA 295.2 215.205 NA NA 327.1 219.831 NA NA 304.0 214.939

NA NA 297.9 215.051 NA NA 328.3 220.775 NA NA 306.4 214.908

NA NA 297.9 214.716 NA NA 329.2 221.388 NA NA 306.4 214.908

NA NA 300.7 214.625 NA NA NA NA NA NA 309.9 214.939

NA NA 303.4 214.594 NA NA NA NA NA NA 309.9 214.939

NA NA 303.4 214.533 NA NA NA NA NA NA 312.3 214.969

NA NA 309.0 214.533 NA NA NA NA NA NA 312.3 214.969

NA NA 309.0 214.503 NA NA NA NA NA NA 314.6 214.939

NA NA 309.0 214.533 NA NA NA NA NA NA 316.9 215.030

NA NA 311.7 214.533 NA NA NA NA NA NA 316.9 215.030

NA NA 314.5 214.533 NA NA NA NA NA NA 319.3 215.183

NA NA 314.5 214.533 NA NA NA NA NA NA 321.6 215.366

NA NA 317.2 214.564 NA NA NA NA NA NA 321.6 215.366
36 Grain-Size Distribution and Selected Major and Trace Element Concentrations in Bed-Sediment Cores

Appendix 1. Distance from bank and elevation data for cross sections 17, 18, and 24 measured near the confluence of the Clearwater 

and Snake Rivers in eastern Washington and and northern Idaho, 1995 and 2008.—Continued

[dist., distance; left bank, as viewed by looking downstream; m, meters; elevation above the North American Vertical Datum of 1988; NA, not applicable; 1995 

data were digitized from cross sections measured by the U.S. Army Corps of Engineers during 1995; 2008 data were from cross sections measured during 2008; 

data provided by the U.S. Army Corps of Engineers [Gregg Teasdale, U.S. Army Corps of Engineers, written commun., 2010])

Cross section 17 Cross section 18 Cross section 24

1995 2008 1995 2008 1995 2008

Dist. from 

left bank 

(m)

Elevation 

(m)

Dist. from 

left bank 

(m)

Elevation 

(m)

Dist. from 

left bank 

(m)

Elevation 

(m)

Dist. from 

left bank 

(m)

Elevation 

(m)

Dist. from 

left bank 

(m)

Elevation 

(m)

Dist. from 

left bank 

(m)

Elevation 

(m)

NA NA 320.0 214.533 NA NA NA NA NA NA 324.0 215.701

NA NA 320.0 214.533 NA NA NA NA NA NA 326.3 215.670

NA NA 322.7 214.533 NA NA NA NA NA NA 326.3 215.670

NA NA 322.7 214.564 NA NA NA NA NA NA 328.7 215.548

NA NA 325.4 214.777 NA NA NA NA NA NA 331.0 215.609

NA NA 325.4 214.990 NA NA NA NA NA NA 333.3 215.640

NA NA 328.1 215.143 NA NA NA NA NA NA 335.7 215.731

NA NA 328.1 215.234 NA NA NA NA NA NA 335.7 215.731

NA NA 330.8 215.292 NA NA NA NA NA NA 338.1 215.823

NA NA 333.5 215.353 NA NA NA NA NA NA 340.4 215.853

NA NA 333.5 215.505 NA NA NA NA NA NA 342.7 215.853

NA NA 336.1 215.627 NA NA NA NA NA NA 342.7 215.853

NA NA 336.1 215.688 NA NA NA NA NA NA 345.0 215.823

NA NA 336.1 215.780 NA NA NA NA NA NA 347.3 215.884

NA NA 338.8 215.841 NA NA NA NA NA NA 349.6 215.914

NA NA 341.5 215.841 NA NA NA NA NA NA 351.9 215.975

NA NA 341.5 215.902 NA NA NA NA NA NA 354.2 216.006

NA NA 344.1 215.902 NA NA NA NA NA NA 354.2 216.006

NA NA 346.8 215.932 NA NA NA NA NA NA 356.5 216.341

NA NA 346.8 215.932 NA NA NA NA NA NA 358.7 217.012

NA NA 349.4 215.932 NA NA NA NA NA NA 358.7 217.012

NA NA 352.1 215.902 NA NA NA NA NA NA 361.0 217.987

NA NA 352.1 215.902 NA NA NA NA NA NA 363.1 218.475

NA NA 354.8 215.932 NA NA NA NA NA NA 363.1 218.475

NA NA 354.8 215.993 NA NA NA NA NA NA 365.1 219.480

NA NA 357.4 215.993 NA NA NA NA NA NA 366.9 219.755

NA NA 357.4 216.024 NA NA NA NA NA NA 366.9 219.755

NA NA 360.1 215.963 NA NA NA NA NA NA 368.5 220.456

NA NA 360.1 215.993 NA NA NA NA NA NA 369.8 220.700

NA NA 362.8 216.115 NA NA NA NA NA NA 370.7 221.279

NA NA 362.8 216.420 NA NA NA NA NA NA 370.7 221.279

NA NA 365.5 216.511 NA NA NA NA NA NA NA NA 

NA NA 365.5 216.511 NA NA NA NA NA NA NA NA 

NA NA 368.2 216.542 NA NA NA NA NA NA NA NA 

NA NA 368.2 216.755 NA NA NA NA NA NA NA NA 
Appendix 1 37

Appendix 1. Distance from bank and elevation data for cross sections 17, 18, and 24 measured near the confluence of the Clearwater 

and Snake Rivers in eastern Washington and and northern Idaho, 1995 and 2008.—Continued

[dist., distance; left bank, as viewed by looking downstream; m, meters; elevation above the North American Vertical Datum of 1988; NA, not applicable; 1995 

data were digitized from cross sections measured by the U.S. Army Corps of Engineers during 1995; 2008 data were from cross sections measured during 2008; 

data provided by the U.S. Army Corps of Engineers [Gregg Teasdale, U.S. Army Corps of Engineers, written commun., 2010])

Cross section 17 Cross section 18 Cross section 24

1995 2008 1995 2008 1995 2008

Dist. from 

left bank 

(m)

Elevation 

(m)

Dist. from 

left bank 

(m)

Elevation 

(m)

Dist. from 

left bank 

(m)

Elevation 

(m)

Dist. from 

left bank 

(m)

Elevation 

(m)

Dist. from 

left bank 

(m)

Elevation 

(m)

Dist. from 

left bank 

(m)

Elevation 

(m)

NA NA 370.8 216.908 NA NA NA NA NA NA NA NA 

NA NA 370.8 216.969 NA NA NA NA NA NA NA NA 

NA NA 373.6 216.999 NA NA NA NA NA NA NA NA 

NA NA 373.6 217.029 NA NA NA NA NA NA NA NA 

NA NA 376.3 217.090 NA NA NA NA NA NA NA NA 

NA NA 376.3 217.182 NA NA NA NA NA NA NA NA 

NA NA 379.0 217.273 NA NA NA NA NA NA NA NA 

NA NA 379.0 217.395 NA NA NA NA NA NA NA NA 

NA NA 381.7 217.517 NA NA NA NA NA NA NA NA 

NA NA 381.7 217.639 NA NA NA NA NA NA NA NA 

NA NA 384.4 217.731 NA NA NA NA NA NA NA NA 

NA NA 384.4 217.700 NA NA NA NA NA NA NA NA 

NA NA 387.2 217.761 NA NA NA NA NA NA NA NA 

NA NA 387.2 217.761 NA NA NA NA NA NA NA NA 

NA NA 389.9 217.700 NA NA NA NA NA NA NA NA 

NA NA 389.9 217.700 NA NA NA NA NA NA NA NA 

NA NA 392.5 217.883 NA NA NA NA NA NA NA NA 

NA NA 395.2 218.340 NA NA NA NA NA NA NA NA 

NA NA 395.2 218.401 NA NA NA NA NA NA NA NA 

NA NA 397.9 218.371 NA NA NA NA NA NA NA NA 

NA NA 397.9 218.310 NA NA NA NA NA NA NA NA 

NA NA 400.6 218.432 NA NA NA NA NA NA NA NA 

NA NA 403.3 218.767 NA NA NA NA NA NA NA NA 

NA NA 403.3 218.950 NA NA NA NA NA NA NA NA 

NA NA 406.0 218.950 NA NA NA NA NA NA NA NA 

NA NA 406.0 218.950 NA NA NA NA NA NA NA NA 

NA NA 408.6 218.950 NA NA NA NA NA NA NA NA 

NA NA 408.6 218.950 NA NA NA NA NA NA NA NA 

NA NA 411.3 218.950 NA NA NA NA NA NA NA NA 

NA NA 414.0 219.011 NA NA NA NA NA NA NA NA 

NA NA 414.0 219.011 NA NA NA NA NA NA NA NA 

NA NA 416.7 219.041 NA NA NA NA NA NA NA NA 

NA NA 416.7 219.041 NA NA NA NA NA NA NA NA 

NA NA 419.4 219.041 NA NA NA NA NA NA NA NA 

NA NA 422.1 219.011 NA NA NA NA NA NA NA NA 
38 Grain-Size Distribution and Selected Major and Trace Element Concentrations in Bed-Sediment Cores

Appendix 1. Distance from bank and elevation data for cross sections 17, 18, and 24 measured near the confluence of the Clearwater 

and Snake Rivers in eastern Washington and and northern Idaho, 1995 and 2008.—Continued

[dist., distance; left bank, as viewed by looking downstream; m, meters; elevation above the North American Vertical Datum of 1988; NA, not applicable; 1995 

data were digitized from cross sections measured by the U.S. Army Corps of Engineers during 1995; 2008 data were from cross sections measured during 2008; 

data provided by the U.S. Army Corps of Engineers [Gregg Teasdale, U.S. Army Corps of Engineers, written commun., 2010])

Cross section 17 Cross section 18 Cross section 24

1995 2008 1995 2008 1995 2008

Dist. from 

left bank 

(m)

Elevation 

(m)

Dist. from 

left bank 

(m)

Elevation 

(m)

Dist. from 

left bank 

(m)

Elevation 

(m)

Dist. from 

left bank 

(m)

Elevation 

(m)

Dist. from 

left bank 

(m)

Elevation 

(m)

Dist. from 

left bank 

(m)

Elevation 

(m)

NA NA 422.1 218.922 NA NA NA NA NA NA NA NA 

NA NA 424.7 218.861 NA NA NA NA NA NA NA NA 

NA NA 424.7 218.922 NA NA NA NA NA NA NA NA 

NA NA 427.4 219.044 NA NA NA NA NA NA NA NA 

NA NA 427.4 219.288 NA NA NA NA NA NA NA NA 

NA NA 430.1 219.349 NA NA NA NA NA NA NA NA 

NA NA 432.8 219.349 NA NA NA NA NA NA NA NA 

NA NA 432.8 219.379 NA NA NA NA NA NA NA NA 

NA NA 435.5 219.349 NA NA NA NA NA NA NA NA 

NA NA 435.5 219.319 NA NA NA NA NA NA NA NA 

NA NA 438.2 219.319 NA NA NA NA NA NA NA NA 

NA NA 440.9 219.319 NA NA NA NA NA NA NA NA 

NA NA 440.9 219.352 NA NA NA NA NA NA NA NA 

NA NA 443.6 219.291 NA NA NA NA NA NA NA NA 

NA NA 446.3 219.047 NA NA NA NA NA NA NA NA 

NA NA 446.3 218.986 NA NA NA NA NA NA NA NA 

NA NA 446.3 219.047 NA NA NA NA NA NA NA NA 

NA NA 449.0 219.108 NA NA NA NA NA NA NA NA 

NA NA 451.7 219.352 NA NA NA NA NA NA NA NA 

NA NA 451.7 219.413 NA NA NA NA NA NA NA NA 

NA NA 454.4 219.383 NA NA NA NA NA NA NA NA 

NA NA 454.4 219.352 NA NA NA NA NA NA NA NA 

NA NA 457.1 219.230 NA NA NA NA NA NA NA NA 

NA NA 457.1 219.108 NA NA NA NA NA NA NA NA 

NA NA 459.8 219.108 NA NA NA NA NA NA NA NA 

NA NA 459.8 219.108 NA NA NA NA NA NA NA NA 

NA NA 462.5 219.107 NA NA NA NA NA NA NA NA 

NA NA 465.2 219.107 NA NA NA NA NA NA NA NA 

NA NA 465.2 219.168 NA NA NA NA NA NA NA NA 

NA NA 467.9 219.168 NA NA NA NA NA NA NA NA 

NA NA 470.6 219.229 NA NA NA NA NA NA NA NA 

NA NA 470.6 219.290 NA NA NA NA NA NA NA NA 

NA NA 473.3 219.412 NA NA NA NA NA NA NA NA 

NA NA 476.0 219.476 NA NA NA NA NA NA NA NA 

NA NA 476.0 219.476 NA NA NA NA NA NA NA NA 
Appendix 1 39

Appendix 1. Distance from bank and elevation data for cross sections 17, 18, and 24 measured near the confluence of the Clearwater 

and Snake Rivers in eastern Washington and and northern Idaho, 1995 and 2008.—Continued

[dist., distance; left bank, as viewed by looking downstream; m, meters; elevation above the North American Vertical Datum of 1988; NA, not applicable; 1995 

data were digitized from cross sections measured by the U.S. Army Corps of Engineers during 1995; 2008 data were from cross sections measured during 2008; 

data provided by the U.S. Army Corps of Engineers [Gregg Teasdale, U.S. Army Corps of Engineers, written commun., 2010])

Cross section 17 Cross section 18 Cross section 24

1995 2008 1995 2008 1995 2008

Dist. from 

left bank 

(m)

Elevation 

(m)

Dist. from 

left bank 

(m)

Elevation 

(m)

Dist. from 

left bank 

(m)

Elevation 

(m)

Dist. from 

left bank 

(m)

Elevation 

(m)

Dist. from 

left bank 

(m)

Elevation 

(m)

Dist. from 

left bank 

(m)

Elevation 

(m)

NA NA 478.6 219.446 NA NA NA NA NA NA NA NA 

NA NA 478.6 219.415 NA NA NA NA NA NA NA NA 

NA NA 481.3 219.415 NA NA NA NA NA NA NA NA 

NA NA 481.3 219.415 NA NA NA NA NA NA NA NA 

NA NA 484.0 219.415 NA NA NA NA NA NA NA NA 

NA NA 486.7 219.415 NA NA NA NA NA NA NA NA 

NA NA 486.7 219.446 NA NA NA NA NA NA NA NA 

NA NA 489.4 219.446 NA NA NA NA NA NA NA NA 

NA NA 489.4 219.415 NA NA NA NA NA NA NA NA 

NA NA 492.0 219.415 NA NA NA NA NA NA NA NA 

NA NA 492.0 219.354 NA NA NA NA NA NA NA NA 

NA NA 494.7 219.293 NA NA NA NA NA NA NA NA 

NA NA 497.4 219.232 NA NA NA NA NA NA NA NA 

NA NA 497.4 219.141 NA NA NA NA NA NA NA NA 

NA NA 500.1 219.110 NA NA NA NA NA NA NA NA 

NA NA 502.8 219.141 NA NA NA NA NA NA NA NA 

NA NA 502.8 219.232 NA NA NA NA NA NA NA NA 

NA NA 505.4 219.385 NA NA NA NA NA NA NA NA 

NA NA 505.4 219.385 NA NA NA NA NA NA NA NA 

NA NA 508.1 219.385 NA NA NA NA NA NA NA NA 

NA NA 510.8 219.324 NA NA NA NA NA NA NA NA 

NA NA 510.8 219.263 NA NA NA NA NA NA NA NA 

NA NA 513.5 219.171 NA NA NA NA NA NA NA NA 

NA NA 513.5 219.110 NA NA NA NA NA NA NA NA 

NA NA 516.2 219.049 NA NA NA NA NA NA NA NA 

NA NA 516.2 219.202 NA NA NA NA NA NA NA NA 

NA NA 518.9 219.293 NA NA NA NA NA NA NA NA 

NA NA 518.9 219.232 NA NA NA NA NA NA NA NA 

NA NA 521.6 219.171 NA NA NA NA NA NA NA NA 

NA NA 524.3 219.141 NA NA NA NA NA NA NA NA 

NA NA 524.3 219.049 NA NA NA NA NA NA NA NA 

NA NA 527.0 219.019 NA NA NA NA NA NA NA NA 

NA NA 529.7 219.229 NA NA NA NA NA NA NA NA 

NA NA 529.7 219.412 NA NA NA NA NA NA NA NA 

NA NA 529.7 219.412 NA NA NA NA NA NA NA NA 
40 Grain-Size Distribution and Selected Major and Trace Element Concentrations in Bed-Sediment Cores

Appendix 1. Distance from bank and elevation data for cross sections 17, 18, and 24 measured near the confluence of the Clearwater 

and Snake Rivers in eastern Washington and and northern Idaho, 1995 and 2008.—Continued

[dist., distance; left bank, as viewed by looking downstream; m, meters; elevation above the North American Vertical Datum of 1988; NA, not applicable; 1995 

data were digitized from cross sections measured by the U.S. Army Corps of Engineers during 1995; 2008 data were from cross sections measured during 2008; 

data provided by the U.S. Army Corps of Engineers [Gregg Teasdale, U.S. Army Corps of Engineers, written commun., 2010])

Cross section 17 Cross section 18 Cross section 24

1995 2008 1995 2008 1995 2008

Dist. from 

left bank 

(m)

Elevation 

(m)

Dist. from 

left bank 

(m)

Elevation 

(m)

Dist. from 

left bank 

(m)

Elevation 

(m)

Dist. from 

left bank 

(m)

Elevation 

(m)

Dist. from 

left bank 

(m)

Elevation 

(m)

Dist. from 

left bank 

(m)

Elevation 

(m)

NA NA 532.4 219.351 NA NA NA NA NA NA NA NA 

NA NA 535.1 219.260 NA NA NA NA NA NA NA NA 

NA NA 535.1 219.229 NA NA NA NA NA NA NA NA 

NA NA 537.8 219.168 NA NA NA NA NA NA NA NA 

NA NA 537.8 219.077 NA NA NA NA NA NA NA NA 

NA NA 540.5 219.016 NA NA NA NA NA NA NA NA 

NA NA 540.5 218.894 NA NA NA NA NA NA NA NA 

NA NA 543.2 219.138 NA NA NA NA NA NA NA NA 

NA NA 545.8 219.199 NA NA NA NA NA NA NA NA 

NA NA 545.8 219.168 NA NA NA NA NA NA NA NA 

NA NA 548.5 219.229 NA NA NA NA NA NA NA NA 

NA NA 548.5 219.199 NA NA NA NA NA NA NA NA 

NA NA 551.2 219.168 NA NA NA NA NA NA NA NA 

NA NA 551.2 219.077 NA NA NA NA NA NA NA NA 

NA NA 553.9 218.955 NA NA NA NA NA NA NA NA 

NA NA 556.5 218.803 NA NA NA NA NA NA NA NA 

NA NA 556.5 218.711 NA NA NA NA NA NA NA NA 

NA NA 559.1 218.650 NA NA NA NA NA NA NA NA 

NA NA 561.8 218.955 NA NA NA NA NA NA NA NA 

NA NA 561.8 219.077 NA NA NA NA NA NA NA NA 

NA NA 564.4 219.046 NA NA NA NA NA NA NA NA 

NA NA 564.4 218.985 NA NA NA NA NA NA NA NA 

NA NA 567.1 218.894 NA NA NA NA NA NA NA NA 

NA NA 567.1 218.891 NA NA NA NA NA NA NA NA 

NA NA 569.7 218.830 NA NA NA NA NA NA NA NA 

NA NA 572.3 218.739 NA NA NA NA NA NA NA NA 

NA NA 572.3 218.708 NA NA NA NA NA NA NA NA 

NA NA 574.9 218.708 NA NA NA NA NA NA NA NA 

NA NA 577.5 218.647 NA NA NA NA NA NA NA NA 

NA NA 577.5 218.525 NA NA NA NA NA NA NA NA 

NA NA 580.1 218.373 NA NA NA NA NA NA NA NA 

NA NA 580.1 218.251 NA NA NA NA NA NA NA NA 

NA NA 582.7 218.159 NA NA NA NA NA NA NA NA 

NA NA 585.2 218.129 NA NA NA NA NA NA NA NA 

NA NA 585.2 218.068 NA NA NA NA NA NA NA NA 
Appendix 1 41

Appendix 1. Distance from bank and elevation data for cross sections 17, 18, and 24 measured near the confluence of the Clearwater 

and Snake Rivers in eastern Washington and and northern Idaho, 1995 and 2008.—Continued

[dist., distance; left bank, as viewed by looking downstream; m, meters; elevation above the North American Vertical Datum of 1988; NA, not applicable; 1995 

data were digitized from cross sections measured by the U.S. Army Corps of Engineers during 1995; 2008 data were from cross sections measured during 2008; 

data provided by the U.S. Army Corps of Engineers [Gregg Teasdale, U.S. Army Corps of Engineers, written commun., 2010])

Cross section 17 Cross section 18 Cross section 24

1995 2008 1995 2008 1995 2008

Dist. from 

left bank 

(m)

Elevation 

(m)

Dist. from 

left bank 

(m)

Elevation 

(m)

Dist. from 

left bank 

(m)

Elevation 

(m)

Dist. from 

left bank 

(m)

Elevation 

(m)

Dist. from 

left bank 

(m)

Elevation 

(m)

Dist. from 

left bank 

(m)

Elevation 

(m)

NA NA 587.8 218.037 NA NA NA NA NA NA NA NA 

NA NA 590.3 217.977 NA NA NA NA NA NA NA NA 

NA NA 590.3 217.885 NA NA NA NA NA NA NA NA 

NA NA 592.8 217.824 NA NA NA NA NA NA NA NA 

NA NA 592.8 217.733 NA NA NA NA NA NA NA NA 

NA NA 595.3 217.702 NA NA NA NA NA NA NA NA 

NA NA 595.3 217.611 NA NA NA NA NA NA NA NA 

NA NA 597.8 217.550 NA NA NA NA NA NA NA NA 

NA NA 600.3 217.611 NA NA NA NA NA NA NA NA 

NA NA 600.3 217.580 NA NA NA NA NA NA NA NA 

NA NA 602.8 217.489 NA NA NA NA NA NA NA NA 

NA NA 602.8 217.367 NA NA NA NA NA NA NA NA 

NA NA 605.3 217.275 NA NA NA NA NA NA NA NA 

NA NA 605.3 217.275 NA NA NA NA NA NA NA NA 

NA NA 607.8 217.489 NA NA NA NA NA NA NA NA 

NA NA 607.8 217.489 NA NA NA NA NA NA NA NA 

NA NA 610.3 217.397 NA NA NA NA NA NA NA NA 

NA NA 612.8 217.306 NA NA NA NA NA NA NA NA 

NA NA 612.8 217.154 NA NA NA NA NA NA NA NA 

NA NA 615.3 217.001 NA NA NA NA NA NA NA NA 

NA NA 615.3 216.757 NA NA NA NA NA NA NA NA 

NA NA 617.8 216.574 NA NA NA NA NA NA NA NA 

NA NA 620.3 216.544 NA NA NA NA NA NA NA NA 

NA NA 620.3 216.513 NA NA NA NA NA NA NA NA 

NA NA 622.7 216.178 NA NA NA NA NA NA NA NA 

NA NA 625.2 216.453 NA NA NA NA NA NA NA NA 

NA NA 625.2 216.574 NA NA NA NA NA NA NA NA 

NA NA 630.1 216.574 NA NA NA NA NA NA NA NA 

NA NA 630.1 216.482 NA NA NA NA NA NA NA NA 

NA NA 632.6 216.330 NA NA NA NA NA NA NA NA 

NA NA 635.0 216.208 NA NA NA NA NA NA NA NA 

NA NA 635.0 216.086 NA NA NA NA NA NA NA NA 

NA NA 637.4 215.933 NA NA NA NA NA NA NA NA 

NA NA 637.4 215.842 NA NA NA NA NA NA NA NA 

NA NA 639.9 215.781 NA NA NA NA NA NA NA NA 
42 Grain-Size Distribution and Selected Major and Trace Element Concentrations in Bed-Sediment Cores

Appendix 1. Distance from bank and elevation data for cross sections 17, 18, and 24 measured near the confluence of the Clearwater 

and Snake Rivers in eastern Washington and and northern Idaho, 1995 and 2008.—Continued

[dist., distance; left bank, as viewed by looking downstream; m, meters; elevation above the North American Vertical Datum of 1988; NA, not applicable; 1995 

data were digitized from cross sections measured by the U.S. Army Corps of Engineers during 1995; 2008 data were from cross sections measured during 2008; 

data provided by the U.S. Army Corps of Engineers [Gregg Teasdale, U.S. Army Corps of Engineers, written commun., 2010])

Cross section 17 Cross section 18 Cross section 24

1995 2008 1995 2008 1995 2008

Dist. from 

left bank 

(m)

Elevation 

(m)

Dist. from 

left bank 

(m)

Elevation 

(m)

Dist. from 

left bank 

(m)

Elevation 

(m)

Dist. from 

left bank 

(m)

Elevation 

(m)

Dist. from 

left bank 

(m)

Elevation 

(m)

Dist. from 

left bank 

(m)

Elevation 

(m)

NA NA 642.3 215.933 NA NA NA NA NA NA NA NA 

NA NA 642.3 215.994 NA NA NA NA NA NA NA NA 

NA NA 644.7 215.964 NA NA NA NA NA NA NA NA 

NA NA 647.1 215.994 NA NA NA NA NA NA NA NA 

NA NA 647.1 216.025 NA NA NA NA NA NA NA NA 

NA NA 649.6 215.994 NA NA NA NA NA NA NA NA 

NA NA 649.6 215.964 NA NA NA NA NA NA NA NA 

NA NA 652.0 215.872 NA NA NA NA NA NA NA NA 

NA NA 652.0 215.751 NA NA NA NA NA NA NA NA 

NA NA 654.4 215.598 NA NA NA NA NA NA NA NA 

NA NA 656.9 215.385 NA NA NA NA NA NA NA NA 

NA NA 656.9 215.415 NA NA NA NA NA NA NA NA 

NA NA 656.9 215.415 NA NA NA NA NA NA NA NA 

NA NA 661.9 215.537 NA NA NA NA NA NA NA NA 

NA NA 661.9 215.659 NA NA NA NA NA NA NA NA 

NA NA 661.9 215.629 NA NA NA NA NA NA NA NA 

NA NA 664.3 215.537 NA NA NA NA NA NA NA NA 

NA NA 666.8 215.443 NA NA NA NA NA NA NA NA 

NA NA 666.8 215.321 NA NA NA NA NA NA NA NA 

NA NA 669.3 215.229 NA NA NA NA NA NA NA NA 

NA NA 669.3 215.138 NA NA NA NA NA NA NA NA 

NA NA 671.7 214.985 NA NA NA NA NA NA NA NA 

NA NA 674.2 214.894 NA NA NA NA NA NA NA NA 

NA NA 674.2 214.772 NA NA NA NA NA NA NA NA 

NA NA 676.6 214.711 NA NA NA NA NA NA NA NA 

NA NA 676.6 214.589 NA NA NA NA NA NA NA NA 

NA NA 679.1 214.498 NA NA NA NA NA NA NA NA 

NA NA 681.6 214.437 NA NA NA NA NA NA NA NA 

NA NA 681.6 214.315 NA NA NA NA NA NA NA NA 

NA NA 684.1 214.196 NA NA NA NA NA NA NA NA 

NA NA 686.6 214.105 NA NA NA NA NA NA NA NA 

NA NA 686.6 214.074 NA NA NA NA NA NA NA NA 

NA NA 689.1 214.196 NA NA NA NA NA NA NA NA 

NA NA 691.6 214.288 NA NA NA NA NA NA NA NA 

NA NA 691.6 214.288 NA NA NA NA NA NA NA NA 
Appendix 1 43

Appendix 1. Distance from bank and elevation data for cross sections 17, 18, and 24 measured near the confluence of the Clearwater 

and Snake Rivers in eastern Washington and and northern Idaho, 1995 and 2008.—Continued

[dist., distance; left bank, as viewed by looking downstream; m, meters; elevation above the North American Vertical Datum of 1988; NA, not applicable; 1995 

data were digitized from cross sections measured by the U.S. Army Corps of Engineers during 1995; 2008 data were from cross sections measured during 2008; 

data provided by the U.S. Army Corps of Engineers [Gregg Teasdale, U.S. Army Corps of Engineers, written commun., 2010])

Cross section 17 Cross section 18 Cross section 24

1995 2008 1995 2008 1995 2008

Dist. from 

left bank 

(m)

Elevation 

(m)

Dist. from 

left bank 

(m)

Elevation 

(m)

Dist. from 

left bank 

(m)

Elevation 

(m)

Dist. from 

left bank 

(m)

Elevation 

(m)

Dist. from 

left bank 

(m)

Elevation 

(m)

Dist. from 

left bank 

(m)

Elevation 

(m)

NA NA 694.1 214.288 NA NA NA NA NA NA NA NA 

NA NA 696.5 214.653 NA NA NA NA NA NA NA NA 

NA NA 696.5 214.958 NA NA NA NA NA NA NA NA 

NA NA 699.0 215.354 NA NA NA NA NA NA NA NA 

NA NA 699.0 215.507 NA NA NA NA NA NA NA NA 

NA NA 701.5 215.751 NA NA NA NA NA NA NA NA 

NA NA 701.5 215.933 NA NA NA NA NA NA NA NA 

NA NA 704.0 215.903 NA NA NA NA NA NA NA NA 

NA NA 706.5 215.872 NA NA NA NA NA NA NA NA 

NA NA 706.5 215.812 NA NA NA NA NA NA NA NA 

NA NA 708.9 215.690 NA NA NA NA NA NA NA NA 

NA NA 711.4 215.568 NA NA NA NA NA NA NA NA 

NA NA 713.9 215.568 NA NA NA NA NA NA NA NA 

NA NA 713.9 215.632 NA NA NA NA NA NA NA NA 

NA NA 713.9 215.601 NA NA NA NA NA NA NA NA 

NA NA 718.8 215.601 NA NA NA NA NA NA NA NA 

NA NA 718.8 215.632 NA NA NA NA NA NA NA NA 

NA NA 721.2 215.662 NA NA NA NA NA NA NA NA 

NA NA 723.7 215.754 NA NA NA NA NA NA NA NA 

NA NA 726.0 216.028 NA NA NA NA NA NA NA NA 

NA NA 726.0 216.180 NA NA NA NA NA NA NA NA 

NA NA 728.4 216.485 NA NA NA NA NA NA NA NA 

NA NA 728.4 216.820 NA NA NA NA NA NA NA NA 

NA NA 730.6 217.369 NA NA NA NA NA NA NA NA 

NA NA 732.7 217.704 NA NA NA NA NA NA NA NA 

NA NA 732.7 218.314 NA NA NA NA NA NA NA NA 

NA NA 734.7 218.893 NA NA NA NA NA NA NA NA 

NA NA 736.5 219.106 NA NA NA NA NA NA NA NA 

NA NA 738.2 219.536 NA NA NA NA NA NA NA NA 

NA NA 738.2 219.871 NA NA NA NA NA NA NA NA 

NA NA 739.7 220.329 NA NA NA NA NA NA NA NA 

NA NA 741.0 220.938 NA NA NA NA NA NA NA NA 

Appendix 2—Grain-Size Data from Bed-Sediment Core Samples

Appendix 2
46 Grain-Size Distribution and Selected Major and Trace Element Concentrations in Bed-Sediment Cores

Appendix 2. Grain-size data from bed-sediment core samples collected in Lower Granite Reservoir and the Clearwater and Snake 

Rivers just above their confluence, 2010.—Continued

[# , number; cm, centimeter; mm, millimeter; --, not analyzed]

USGS station 

number

Core 

identifier

Core 

sample 

interval 

analyzed

(cm)

Sample 

identifier Date

Percent 

finer than 

16 mm; 

coarse/

medium 

pebbles

Percent 

finer than 

8 mm; 

medium/fine 

pebbles

Percent 

finer than 

4 mm; 

fine/

very fine 

pebbles

Percent 

finer than 

2 mm; 

very fine 

pebbles/

very coarse 

sand

Percent 

finer than 

1 mm; very 

coarse 

sand/

coarse 

sand

Percent 

finer than 

0.50 mm; 

coarse/

medium 

sand

Clearwater River

462534117015500 1 0–5 Core #1 0–5 5/14/10 -- -- -- 100.0 97.9 94.9

462534117015500 1 9–12 Core #1 9–12 5/14/10 -- -- -- -- 99.7 94.2

462537117015600 2 60–63 Core #2 60–63 5/13/10 -- -- -- -- 100.0 98.0

462537117015600 2 80–83 Core #2 80–83 5/13/10 -- -- -- 100.0 99.9 99.9

462537117015600 2 105–108 Core #2 105–108 5/13/10 -- -- -- -- 100.0 99.7

462535117015700 3 2–5 Core #3 2–5 5/14/10 -- -- -- 100.0 99.9 98.2

462535117015700 3 28–31 Core #3 28–31 5/14/10 -- -- -- 100.0 99.8 98.5

462535117015700 3 62–65 Core #3 62–65 5/14/10 -- -- -- -- -- 100.0

462535117015700 3 90–93 Core #3 90–93 5/14/10 -- -- -- -- 100.0 99.9

462535117015700 3 114–117 Core #3 114–117 5/14/10 -- -- -- -- -- 100.0

462535117015700 3 123–126 Core #3 123–126 5/14/10 -- -- -- -- 100.0 99.5

462532117014900 4 22–25 Core #4 22–25 5/13/10 -- -- -- 100.0 99.7 94.8

462532117014900 4 44–47 Core #4 44–47 5/13/10 -- -- -- 100.0 99.8 94.4

462535117014800 5 0–2 Core #5 0–2 5/14/10 -- -- -- 100.0 99.6 97.8

462535117014800 5 4–6 Core #5 4–6 5/14/10 -- -- -- 100.0 99.7 96.6

462535117014800 5 20–22 Core #5 20–22 5/14/10 -- -- -- 100.0 99.8 96.0

462535117014800 5 43–45 Core #5 43–45 5/14/10 -- -- -- 100.0 99.2 96.7

462527117011300 7 0–2 Core #7 0–2 5/18/10 -- 100.0 99.5 98.7 98.3 76.4

462532117011101 9 18–21 Core #9 18–21 5/13/10 -- -- -- -- 100.0 99.9

462532117011101 9 34–37 Core #9 34–37 5/13/10 -- -- -- -- 100.0 99.7

462532117011101 9 50–53 Core #9 50–53 5/13/10 -- -- -- -- -- 100.0

462517117010300 10 0–1 Core #10 0–1 5/13/10 -- -- -- 100.0 99.7 90.2

462517117010300 10 20–23 Core #10 20–23 5/13/10 -- -- 100.0 99.6 98.5 67.8

462517117010300 10 80–83 Core #10 80–83 5/13/10 -- -- -- -- 100.0 99.3

462517117010300 10 108–110 Core #10 108–110 5/13/10 -- 100.0 99.6 99.3 97.9 47.8

462520117005900 11 0–3 Core #11 0–3 5/18/10 -- -- -- 100.0 99.9 81.8

462524117005900 12 0–2 Core #12 0–2 5/13/10 -- -- -- 100.0 99.0 91.7

462524117005900 12 29–32 Core #12 29–32 5/13/10 -- -- -- 100.0 99.9 91.3

462513117004900 13 0–4 Core #13 0–4 5/18/10 -- -- 100.0 99.6 98.5 50.5

462517117004900 14 0–1 Core #14 0–1 5/18/10 -- -- -- 100.0 99.6 84.5

462517117004900 14 2–5 Core #14 2–5 5/18/10 -- -- -- 100.0 99.8 68.9

462517117004900 14 54–56 Core #14 54–56 5/18/10 -- -- -- 100.0 99.9 98.0

462520117004700 15 2–5 Core #15 2–5 5/18/10 -- -- -- -- 100.0 87.8

462520117004700 15 17–20 Core #15 17–20 5/18/10 -- -- -- 100.0 99.3 80.5

462520117004700 15 22–25 Core #15 22–25 5/18/10 -- -- -- 100.0 99.6 91.5

Appendix 2. Grain-size data from bed-sediment core samples collected in Lower Granite Reservoir and the Clearwater and Snake 

Rivers just above their confluence, 2010.

[# , number; cm, centimeter; mm, millimeter; --, not analyzed]
Appendix 2 47

Appendix 2. Grain-size data from bed-sediment core samples collected in Lower Granite Reservoir and the Clearwater and Snake 

Rivers just above their confluence, 2010.—Continued

[# , number; cm, centimeter; mm, millimeter; --, not analyzed]

Sample 

identifier Date

Percent 

finer than 

0.25 mm; 

medium/ 

fine sand

Percent 

finer than 

0.125 mm; 

fine/very 

fine sand

Percent 

finer than 

0.0625 mm; 

very fine 

sand/

coarse 

silt

Percent 

finer than 

0.031 mm; 

coarse/

medium 

silt

Percent 

finer than 

0.016 mm; 

medium/

fine silt

Percent 

finer than 

0.008 mm; 

fine/very 

fine silt

Percent 

finer than 

0.004 mm; 

very fine 

silt/clay

Percent 

finer than 

0.002 mm; 

silt/clay 

for mineral 

analysis

Percent 

finer than 

0.001 mm; 

finer than 

clay

Clearwater River

Core #1 0–5 5/14/10 62.2 48.2 17.2 16.1 12.8 9.8 7.6 5.8 3.6

Core #1 9–12 5/14/10 16.9 1.4 0.7 -- -- -- -- -- --

Core #2 60–63 5/13/10 40.5 3.4 1.2 -- -- -- -- -- --

Core #2 80–83 5/13/10 99.2 97.8 83.0 55.1 32.3 24.8 19.3 15.5 11.3

Core #2 105–108 5/13/10 93.8 12.6 3.1 -- -- -- -- -- --

Core #3 2–5 5/14/10 48.7 2.3 0.6 -- -- -- -- -- --

Core #3 28–31 5/14/10 62.2 10.7 3.0 -- -- -- -- -- --

Core #3 62–65 5/14/10 99.9 99.5 94.0 70.7 45.7 34.4 27.0 21.5 17.8

Core #3 90–93 5/14/10 95.1 14.7 2.8 -- -- -- -- -- --

Core #3 114–117 5/14/10 99.8 97.5 90.2 72.0 45.8 34.4 25.8 21.1 20.3

Core #3 123–126 5/14/10 97.1 59.5 38.1 29.4 19.6 14.6 11.2 8.4 7.9

Core #4 22–25 5/13/10 8.9 1.2 0.6 -- -- -- -- -- --

Core #4 44–47 5/13/10 20.0 2.9 1.8 -- -- -- -- -- --

Core #5 0–2 5/14/10 75.4 61.4 53.1 49.6 40.6 30.9 23.8 18.7 11.7

Core #5 4–6 5/14/10 27.0 1.5 0.6 -- -- -- -- -- --

Core #5 20–22 5/14/10 25.1 1.6 0.6 -- -- -- -- -- --

Core #5 43–45 5/14/10 48.9 8.3 2.5 -- -- -- -- -- --

Core #7 0–2 5/18/10 23.2 8.5 5.4 5.0 3.8 2.6 1.9 1.4 0.6

Core #9 18–21 5/13/10 98.8 95.7 87.7 66.4 42.5 32.4 25.5 20.5 14.2

Core #9 34–37 5/13/10 72.5 29.0 20.5 16.2 11.4 9.4 7.5 6.0 4.1

Core #9 50–53 5/13/10 99.8 98.7 94.9 78.9 51.3 36.1 26.9 20.9 14.9

Core #10 0–1 5/13/10 60.5 55.4 49.4 45.4 35.7 27.3 21.9 17.5 15.8

Core #10 20–23 5/13/10 9.9 0.9 0.4 -- -- -- -- -- --

Core #10 80–83 5/13/10 98.0 97.2 93.5 78.0 51.1 38.2 28.9 23.8 18.4

Core #10 108–110 5/13/10 10.5 2.9 0.5 -- -- -- -- -- --

Core #11 0–3 5/18/10 12.7 3.8 1.8 -- -- -- -- -- --

Core #12 0–2 5/13/10 37.5 27.4 20.7 18.9 14.3 10.6 8.2 6.3 5.0

Core #12 29–32 5/13/10 13.0 1.7 0.3 -- -- -- -- -- --

Core #13 0–4 5/18/10 15.0 11.1 7.4 6.7 5.0 4.0 3.1 2.5 2.5

Core #14 0–1 5/18/10 50.5 38.7 29.8 28.0 20.8 14.7 10.9 8.6 6.7

Core #14 2–5 5/18/10 5.1 0.8 0.4 -- -- -- -- -- --

Core #14 54–56 5/18/10 83.0 70.9 66.9 62.9 50.2 35.3 26.5 20.4 17.1

Core #15 2–5 5/18/10 11.5 1.1 0.3 -- -- -- -- -- --

Core #15 17–20 5/18/10 8.5 2.1 0.6 -- -- -- -- -- --

Core #15 22–25 5/18/10 12.2 1.8 0.4 -- -- -- -- -- --
48 Grain-Size Distribution and Selected Major and Trace Element Concentrations in Bed-Sediment Cores

Appendix 2. Grain-size data from bed-sediment core samples collected in Lower Granite Reservoir and the Clearwater and Snake 

Rivers just above their confluence, 2010.—Continued

[# , number; cm, centimeter; mm, millimeter; --, not analyzed]

USGS station 

number

Core 

identifier

Core 

sample 

interval 

analyzed

(cm)

Sample 

identifier Date

Percent 

finer than 

16 mm; 

coarse/

medium 

pebbles

Percent 

finer than 

8 mm; 

medium/fine 

pebbles

Percent 

finer than 

4 mm; 

fine/

very fine 

pebbles

Percent 

finer than 

2 mm; 

very fine 

pebbles/

very coarse 

sand

Percent 

finer than 

1 mm; very 

coarse 

sand/

coarse 

sand

Percent 

finer than 

0.50 mm; 

coarse/

medium 

sand

Clearwater River—Continued

462520117004700 15 45–48 Core #15 45–48 5/18/10 -- -- -- 100.0 98.4 86.8

462520117004700 15 58–61 Core #15 58–61 5/18/10 -- -- -- 100.0 99.9 95.7

462511117002800 16 0–3 Core #16 0–3 5/18/10 -- -- -- -- -- --

462512117002500 17 0–3 Core #17 0–3 5/18/10 -- -- -- -- 100.0 90.8

462515117002400 18 0–3 Core #18 0–3 5/18/10 -- -- -- 100.0 99.9 90.6

Lower Granite Reservoir

463914117245400 19 0–5 Core #19 0–5 4/7/10 -- -- -- -- -- --

463914117245400 19 65–70 Core #19 65–70 4/7/10 -- -- -- -- -- --

463914117245400 19 170–175 Core #19 170–175 4/7/10 -- -- -- -- -- --

463921117245200 20 0–10 Core #20 0–10 4/7/10 -- -- -- -- -- --

463921117245200 20 147–157 Core #20 147–157 4/7/10 -- -- -- -- -- --

463921117245200 20 224–229 Core #20 224–229 4/7/10 -- -- -- -- -- --

463930117244800 21 0–10 Core #21 0–10 4/7/10 -- -- -- -- -- --

463930117244800 21 21–27 Core #21 21–27 4/7/10 -- -- -- -- 100.0 99.8

463930117244800 21 30–35 Core #21 30–35 4/7/10 -- -- -- 100.0 99.7 98.3

463749117232500 22 0–5 Core #22 0–5 4/7/10 -- -- -- -- -- --

463749117232500 22 92–97 Core #22 92–97 4/7/10 -- -- -- -- -- --

463749117232500 22 158–162 Core #22 158–162 4/7/10 -- -- -- -- -- 100.0

463748117231500 23 0–5 Core #23 0–5 4/7/10 -- -- -- -- -- --

463748117231500 23 50–55 Core #23 50–55 4/7/10 -- -- -- -- 100.0 99.3

463748117231500 23 161–164 Core #23 161–164 4/7/10 -- -- -- 100.0 99.7 95.7

463745117225500 24 sample 1 Core #24 sample 1 4/6/10 100.0 92.8 76.8 73.7 69.7 66.7

463745117225500 24 sample 2 Core #24 sample 2 4/6/10 100.0 61.6 36.7 35.6 33.4 31.7

463516117210100 25 0–5 Core #25 0–5 4/7/10 -- -- -- -- -- --

463516117210100 25 20–25 Core #25 20–25 4/7/10 -- -- -- -- -- --

463516117210100 25 41–46 Core #25 41–46 4/7/10 -- -- -- -- -- --

463519117205200 26 0–5 Core #26 0–5 4/7/10 -- -- -- -- -- --

463519117205200 26 60–65 Core #26 60–65 4/7/10 -- -- -- -- -- --

463519117205200 26 120–125 Core #26 120–125 4/7/10 -- -- -- -- -- --

463521117204600 27 0–5 Core #27 0–5 4/7/10 -- -- -- -- -- --

463521117204600 27 90–95 Core #27 90–95 4/7/10 -- -- -- -- -- --

463521117204600 27 150–155 Core #27 150–155 4/7/10 -- -- -- -- -- --

463521117204600 27 239–244 Core #27 239–244 4/7/10 -- -- -- -- -- --

463316117161800 28 15–20 Core #28 15–20 4/6/10 -- -- -- -- -- --

463316117161800 28 55–60 Core #28 55–60 4/6/10 -- -- -- -- -- --

463316117161800 28 98–102 Core #28 98–102 4/6/10 -- -- -- -- -- --
Appendix 2 49

Appendix 2. Grain-size data from bed-sediment core samples collected in Lower Granite Reservoir and the Clearwater and Snake 

Rivers just above their confluence, 2010.—Continued

[# , number; cm, centimeter; mm, millimeter; --, not analyzed]

Sample 

identifier Date

Percent 

finer than 

0.25 mm; 

medium/ 

fine sand

Percent 

finer than 

0.125 mm; 

fine/very 

fine sand

Percent 

finer than 

0.0625 mm; 

very fine 

sand/

coarse 

silt

Percent 

finer than 

0.031 mm; 

coarse/

medium 

silt

Percent 

finer than 

0.016 mm; 

medium/

fine silt

Percent 

finer than 

0.008 mm; 

fine/very 

fine silt

Percent 

finer than 

0.004 mm; 

very fine 

silt/clay

Percent 

finer than 

0.002 mm; 

silt/clay 

for mineral 

analysis

Percent 

finer than 

0.001 mm; 

finer than 

clay

Clearwater River—Continued

Core #15 45–48 5/18/10 20.8 2.3 1.0 -- -- -- -- -- --

Core #15 58–61 5/18/10 34.0 13.5 10.4 9.6 7.9 6.2 4.9 3.8 3.2

Core #16 0–3 5/18/10 -- -- 97.2 93.3 72.3 59.9 45.4 34.7 21.3

Core #17 0–3 5/18/10 66.6 61.7 59.0 56.8 42.0 31.9 24.5 19.7 17.2

Core #18 0–3 5/18/10 18.3 7.9 4.6 -- -- -- -- -- --

Lower Granite Reservoir

Core #19 0–5 4/7/10 -- -- 98.8 96.8 80.1 52.9 33.3 22.9 16.7

Core #19 65–70 4/7/10 -- -- 99.9 97.1 82.6 54.9 36.3 26.8 17.1

Core #19 170–175 4/7/10 -- -- 99.7 95.6 77.1 44.9 26.0 17.1 14.1

Core #20 0–10 4/7/10 -- -- 99.7 97.9 83.5 56.4 33.3 22.5 13.8

Core #20 147–157 4/7/10 -- -- 99.8 97.8 85.0 52.5 28.3 17.8 10.9

Core #20 224–229 4/7/10 -- -- 99.7 97.0 79.1 51.8 31.7 22.5 14.1

Core #21 0–10 4/7/10 -- -- 96.4 88.8 66.7 42.9 27.2 18.9 13.1

Core #21 21–27 4/7/10 98.6 89.6 62.3 51.1 37.2 24.5 16.0 11.8 8.5

Core #21 30–35 4/7/10 92.9 80.2 55.0 46.6 35.6 23.7 16.0 11.5 7.5

Core #22 0–5 4/7/10 -- -- 99.1 95.9 78.2 49.7 31.2 22.8 16.0

Core #22 92–97 4/7/10 -- -- 99.7 97.0 83.1 57.4 36.8 24.8 17.3

Core #22 158–162 4/7/10 99.9 99.8 99.2 94.9 77.3 50.1 31.2 21.3 13.2

Core #23 0–5 4/7/10 -- -- 98.4 92.1 67.2 40.8 27.0 20.1 14.1

Core #23 50–55 4/7/10 97.1 96.8 96.1 90.5 67.1 44.3 30.2 22.5 16.6

Core #23 161–164 4/7/10 83.8 78.4 71.8 62.8 47.6 31.0 20.2 14.3 9.2

Core #24 sample 1 4/6/10 63.5 60.1 55.0 44.6 30.0 19.9 13.4 8.9 5.8

Core #24 sample 2 4/6/10 29.7 27.8 25.2 19.6 12.6 7.8 4.9 3.2 2.1

Core #25 0–5 4/7/10 -- -- 97.4 90.2 67.4 39.5 25.1 17.7 11.1

Core #25 20–25 4/7/10 -- -- 97.8 91.7 65.0 41.7 28.7 21.4 14.2

Core #25 41–46 4/7/10 -- -- 98.5 91.6 69.6 43.2 27.8 19.9 12.3

Core #26 0–5 4/7/10 -- -- 97.4 87.9 60.2 36.5 23.6 17.7 15.2

Core #26 60–65 4/7/10 -- -- 98.5 89.2 64.5 39.2 27.5 19.6 17.4

Core #26 120–125 4/7/10 -- -- 98.5 88.7 63.0 38.9 25.1 19.6 14.1

Core #27 0–5 4/7/10 -- -- 98.9 94.1 71.0 43.5 28.9 20.3 10.9

Core #27 90–95 4/7/10 -- -- 98.8 90.5 63.9 37.5 24.7 17.1 12.0

Core #27 150–155 4/7/10 -- -- 97.3 81.4 52.5 30.3 22.3 14.1 5.4

Core #27 239–244 4/7/10 -- -- 99.1 92.1 70.0 43.3 28.5 21.5 17.2

Core #28 15–20 4/6/10 -- -- 98.1 86.9 57.3 36.9 26.8 18.7 15.0

Core #28 55–60 4/6/10 -- -- 99.0 93.0 64.7 43.3 31.5 25.4 20.7

Core #28 98–102 4/6/10 -- -- 94.5 76.9 48.0 29.4 21.5 16.8 12.2
50 Grain-Size Distribution and Selected Major and Trace Element Concentrations in Bed-Sediment Cores

Appendix 2. Grain-size data from bed-sediment core samples collected in Lower Granite Reservoir and the Clearwater and Snake 

Rivers just above their confluence, 2010.—Continued

[# , number; cm, centimeter; mm, millimeter; --, not analyzed]

USGS station 

number

Core 

identifier

Core 

sample 

interval 

analyzed

(cm)

Sample 

identifier Date

Percent 

finer than 

16 mm; 

coarse/

medium 

pebbles

Percent 

finer than 

8 mm; 

medium/fine 

pebbles

Percent 

finer than 

4 mm; 

fine/

very fine 

pebbles

Percent 

finer than 

2 mm; 

very fine 

pebbles/

very coarse 

sand

Percent 

finer than 

1 mm; very 

coarse 

sand/

coarse 

sand

Percent 

finer than 

0.50 mm; 

coarse/

medium 

sand

Lower Granite Reservoir—Continued

463318117161600 29 10–15 Core #29 10–15 4/6/10 -- -- -- -- -- --

463318117161600 29 70–75 Core #29 70–75 4/6/10 -- -- -- -- -- --

463318117161600 29 87–91 Core #29 87–91 4/6/10 -- -- -- -- -- --

463322117161000 30B 0–3 Core #30B 0–3 4/6/10 -- -- -- -- -- --

463322117161000 30B 10–12 Core #30B 10–12 4/6/10 -- -- -- -- -- --

463216117150001 31 10–14 Core #31 10–14 4/6/10 -- -- -- -- 100.0 99.9

463216117150001 31 115–119 Core #31 115–119 4/6/10 -- -- -- -- -- --

463216117150001 31 157–161 Core #31 157–161 4/6/10 -- -- -- -- -- 100.0

463219117145900 32 5–12 Core #32 5–12 4/6/10 -- -- -- -- 100.0 99.5

463219117145900 32 30–35 Core #32 30–35 4/6/10 -- -- -- -- -- --

463219117145900 32 60–64 Core #32 60–64 4/6/10 -- -- -- -- 100.0 99.9

463221117145700 33 3–7 Core #33 3–7 4/6/10 -- -- -- -- -- 100.0

463221117145700 33 14–18 Core #33 14–18 4/6/10 -- -- -- -- -- 100.0

462655117123600 34 8–11 Core #34 8–11 4/9/10 -- -- -- -- 100.0 99.8

462655117123600 34 66–69 Core #34 66–69 4/9/10 -- -- -- -- 100.0 99.9

462655117123600 34 122–125 Core #34 122–125 4/9/10 -- -- -- -- -- 100.0

462655117123600 34 144–147 Core #34 144–147 4/9/10 -- -- -- -- -- --

462655117123600 34 173–176 Core #34 173–176 4/9/10 -- -- -- -- -- 100.0

462520117122001 38 7–10 Core #38 7–10 5/12/10 -- -- -- -- 100.0 99.9

462520117122001 38 12–15 Core #38 12–15 5/12/10 -- -- -- -- -- 100.0

462520117122001 38 60–63 Core #38 60–63 5/12/10 -- -- -- -- 100.0 99.8

462520117122001 38 98–101 Core #38 98–101 5/12/10 -- -- -- -- 100.0 99.9

462520117122001 38 105–108 Core #38 105–108 5/12/10 -- -- -- -- 100.0 99.9

462520117122001 38 155–158 Core #38 155–158 5/12/10 -- -- -- -- -- --

462520117122001 38A 6–8 Core #38A 6–8 4/9/10 -- -- -- 100.0 99.9 99.8

462520117122001 38A 34–36 Core #38A 34–36 4/9/10 -- -- -- -- 100.0 99.7

462520117122001 38A 41–43 Core #38A 41–43 4/9/10 -- -- -- -- 100.0 99.9

462522117121800 39 12–15 Core #39 12–15 5/12/10 -- -- -- -- 100.0 99.6

462522117121800 39 20–23 Core #39 20–23 5/12/10 -- -- -- -- 100.0 99.9

462522117121800 39 87–90 Core #39 87–90 5/12/10 -- -- -- -- 100.0 99.7

462522117121800 39 136–139 Core #39 136–139 5/12/10 -- -- -- -- -- 100.0

462526117102600 40 67–70 Core #40 67–70 5/12/10 -- -- -- -- -- 100.0

462526117102600 40 116–119 Core #40 116–119 5/12/10 -- -- -- -- -- 100.0

462526117102600 40 122–125 Core #40 122–125 5/12/10 -- -- -- -- 100.0 99.9

462526117102600 40 140–143 Core #40 140–143 5/12/10 -- -- -- -- 100.0 99.9
Appendix 2 51

Appendix 2. Grain-size data from bed-sediment core samples collected in Lower Granite Reservoir and the Clearwater and Snake 

Rivers just above their confluence, 2010.—Continued

[# , number; cm, centimeter; mm, millimeter; --, not analyzed]

Sample 

identifier Date

Percent 

finer than 

0.25 mm; 

medium/ 

fine sand

Percent 

finer than 

0.125 mm; 

fine/very 

fine sand

Percent 

finer than 

0.0625 mm; 

very fine 

sand/

coarse 

silt

Percent 

finer than 

0.031 mm; 

coarse/

medium 

silt

Percent 

finer than 

0.016 mm; 

medium/

fine silt

Percent 

finer than 

0.008 mm; 

fine/very 

fine silt

Percent 

finer than 

0.004 mm; 

very fine 

silt/clay

Percent 

finer than 

0.002 mm; 

silt/clay 

for mineral 

analysis

Percent 

finer than 

0.001 mm; 

finer than 

clay

Lower Granite Reservoir—Continued

Core #29 10–15 4/6/10 -- -- 96.4 87.0 62.4 43.0 29.9 22.1 14.9

Core #29 70–75 4/6/10 -- -- 97.6 87.9 64.6 42.3 30.5 23.2 19.4

Core #29 87–91 4/6/10 -- -- 93.5 77.6 47.9 29.7 19.8 14.8 11.4

Core #30B 0–3 4/6/10 -- -- 93.1 79.0 58.8 39.8 26.9 20.3 18.8

Core #30B 10–12 4/6/10 -- -- 92.3 86.8 42.6 46.0 28.6 20.2 17.2

Core #31 10–14 4/6/10 99.8 99.4 85.6 62.1 38.3 26.8 20.5 15.7 14.7

Core #31 115–119 4/6/10 -- -- 95.3 82.4 56.8 38.9 27.4 21.3 19.2

Core #31 157–161 4/6/10 99.8 99.0 77.8 63.4 44.4 31.8 23.2 18.7 11.9

Core #32 5–12 4/6/10 99.2 97.3 83.1 69.7 50.9 36.8 26.5 20.2 11.1

Core #32 30–35 4/6/10 -- -- 96.4 90.2 70.7 49.8 34.6 25.3 22.4

Core #32 60–64 4/6/10 99.4 96.3 61.6 47.2 31.6 21.9 15.9 12.6 8.8

Core #33 3–7 4/6/10 99.7 94.7 56.3 36.9 22.5 15.5 11.5 8.5 5.3

Core #33 14–18 4/6/10 99.8 98.2 76.9 54.1 32.2 22.2 15.9 12.5 9.0

Core #34 8–11 4/9/10 99.2 90.7 70.2 56.9 40.5 28.9 19.9 14.9 11.3

Core #34 66–69 4/9/10 99.2 83.5 38.5 29.8 22.8 18.9 10.1 10.5 9.9

Core #34 122–125 4/9/10 99.9 96.0 75.6 -- -- -- -- -- --

Core #34 144–147 4/9/10 -- -- 92.4 81.7 57.6 42.3 31.9 23.0 18.4

Core #34 173–176 4/9/10 99.9 97.8 85.1 63.9 41.3 28.8 20.6 15.5 9.6

Core #38 7–10 5/12/10 98.9 51.6 37.2 30.1 22.4 17.7 13.6 11.0 10.1

Core #38 12–15 5/12/10 99.7 91.9 84.5 75.3 58.6 48.7 38.2 31.2 26.8

Core #38 60–63 5/12/10 96.1 11.6 1.7 -- -- -- -- -- --

Core #38 98–101 5/12/10 97.4 12.1 1.3 -- -- -- -- -- --

Core #38 105–108 5/12/10 99.6 88.9 79.1 63.8 42.5 31.1 22.9 17.8 11.7

Core #38 155–158 5/12/10 100.0 99.2 96.1 87.7 62.3 42.6 31.8 25.1 17.2

Core #38A 6–8 4/9/10 98.5 60.5 39.5 28.6 19.8 14.5 10.6 7.8 4.9

Core #38A 34–36 4/9/10 99.2 79.1 55.2 37.4 24.2 17.9 13.1 9.4 6.0

Core #38A 41–43 4/9/10 99.7 92.8 86.1 76.1 56.6 40.0 28.2 21.4 15.2

Core #39 12–15 5/12/10 85.9 24.3 4.8 -- -- -- -- -- --

Core #39 20–23 5/12/10 99.5 96.4 58.0 40.9 29.4 24.5 18.6 15.3 13.4

Core #39 87–90 5/12/10 89.2 9.2 2.7 -- -- -- -- -- --

Core #39 136–139 5/12/10 99.9 99.2 90.0 63.3 45.7 35.5 25.4 20.2 16.2

Core #40 67–70 5/12/10 99.4 22.9 1.7 -- -- -- -- -- --

Core #40 116–119 5/12/10 99.9 92.3 86.7 78.0 60.0 44.3 32.8 25.3 21.4

Core #40 122–125 5/12/10 98.4 11.8 3.3 -- -- -- -- -- --

Core #40 140–143 5/12/10 99.7 97.3 75.3 59.3 41.4 30.3 23.3 18.4 14.3
52 Grain-Size Distribution and Selected Major and Trace Element Concentrations in Bed-Sediment Cores

Appendix 2. Grain-size data from bed-sediment core samples collected in Lower Granite Reservoir and the Clearwater and Snake 

Rivers just above their confluence, 2010.—Continued

[# , number; cm, centimeter; mm, millimeter; --, not analyzed]

USGS station 

number

Core 

identifier

Core 

sample 

interval 

analyzed

(cm)

Sample 

identifier Date

Percent 

finer than 

16 mm; 

coarse/

medium 

pebbles

Percent 

finer than 

8 mm; 

medium/fine 

pebbles

Percent 

finer than 

4 mm; 

fine/

very fine 

pebbles

Percent 

finer than 

2 mm; 

very fine 

pebbles/

very coarse 

sand

Percent 

finer than 

1 mm; very 

coarse 

sand/

coarse 

sand

Percent 

finer than 

0.50 mm; 

coarse/

medium 

sand

Lower Granite Reservoir—Continued

462529117102800 41 6–8 Core #41 6–8 5/12/10 -- -- 100.0 99.9 99.5 97.2

462540117081100 43 3–5 Core #43 3–5 5/12/10 -- -- -- 100.0 99.9 99.7

462540117081100 43 15–18 Core #43 15–18 5/12/10 -- -- -- -- 100.0 99.7

462540117081100 43 53–56 Core #43 53–56 5/12/10 -- -- -- -- 100.0 100.0

462540117081100 43 120–123 Core #43 120–123 5/12/10 -- -- -- 100.0 99.4 99.0

462542117081100 44 0–4 Core #44 0–4 5/12/10 -- -- -- 100.0 99.0 96.6

462514117065400 46 50–53 Core #46 50–53 5/13/10 -- -- -- -- 100.0 99.9

462514117065400 46 55–58 Core #46 55–58 5/13/10 -- -- -- -- -- 100.0

462514117065400 46 80–83 Core #46 80–83 5/13/10 -- -- -- -- 100.0 99.8

462514117065400 46 97–100 Core #46 97–100 5/13/10 -- -- -- -- 100.0 99.9

462515117065401 47 5–8 Core #47 5–8 5/13/10 -- -- -- -- 100.0 96.9

462515117065401 47 51–54 Core #47 51–54 5/13/10 -- -- -- 100.0 99.3 98.3

462515117065401 47 109–112 Core #47 109–112 5/13/10 -- -- -- -- 100.0 99.8

462520117065300 48 0–2 Core #48 0–2 5/12/10 -- -- -- 100.0 99.7 95.7

462456117052900 49 2–5 Core #49 2–5 5/14/10 -- -- -- -- 100.0 99.9

462456117052900 49 30–33 Core #49 30–33 5/14/10 -- -- -- -- -- 100.0

462456117052900 49 86–89 Core #49 86–89 5/14/10 -- -- -- -- 100.0 99.6

462456117052900 49 98–101 Core #49 98–101 5/14/10 -- -- -- -- -- 100.0

462456117052900 49 128–131 Core #49 128–131 5/14/10 -- -- -- -- 100.0 99.9

462501117052800 50 0–2 Core #50 0–2 5/14/10 -- -- -- -- 100.0 99.2

462501117052800 50 20–23 Core #50 20–23 5/14/10 -- -- -- -- 100.0 99.6

462501117052800 50 62–65 Core #50 62–65 5/14/10 -- -- -- -- 100.0 99.7

462510117053900 52 0–14 Core #52 0–14 5/14/10 -- -- -- -- -- --

462510117053900 52 16–19 Core #52 16–19 5/14/10 -- -- -- -- -- --

462510117053900 52 54–57 Core #52 54–57 5/14/10 -- -- -- -- -- --

462510117053900 52 104–107 Core #52 104–107 5/14/10 -- -- -- -- -- --

462506117050400 53 0–2 Core #53 0–2 5/12/10 -- -- -- 100.0 99.9 99.5

462506117050400 53 27–30 Core #53 27–30 5/12/10 -- -- -- -- 100.0 99.7

462506117050400 53 63–66 Core #53 63–66 5/12/10 -- -- -- -- 100.0 98.3

462509117050300 54 2–5 Core #54 2–5 5/15/10 -- -- -- 100.0 99.7 94.7

462509117050300 54 73–75 Core #54 73–75 5/15/10 -- -- -- -- 100.0 89.7

462509117050300 54 103–106 Core #54 103–106 5/15/10 -- -- -- 100.0 99.6 94.7

462520117042900 56 0–5 Core #56 0–5 5/15/10 -- -- -- -- 100.0 99.7

462523117042900 57 0–1 Core #57 0–1 5/15/10 -- -- -- -- 100.0 99.7
Appendix 2 53

Appendix 2. Grain-size data from bed-sediment core samples collected in Lower Granite Reservoir and the Clearwater and Snake 

Rivers just above their confluence, 2010.—Continued

[# , number; cm, centimeter; mm, millimeter; --, not analyzed]

Sample 

identifier Date

Percent 

finer than 

0.25 mm; 

medium/ 

fine sand

Percent 

finer than 

0.125 mm; 

fine/very 

fine sand

Percent 

finer than 

0.0625 mm; 

very fine 

sand/

coarse 

silt

Percent 

finer than 

0.031 mm; 

coarse/

medium 

silt

Percent 

finer than 

0.016 mm; 

medium/

fine silt

Percent 

finer than 

0.008 mm; 

fine/very 

fine silt

Percent 

finer than 

0.004 mm; 

very fine 

silt/clay

Percent 

finer than 

0.002 mm; 

silt/clay 

for mineral 

analysis

Percent 

finer than 

0.001 mm; 

finer than 

clay

Lower Granite Reservoir—Continued

Core #41 6–8 5/12/10 51.8 2.4 0.7 -- -- -- -- -- --

Core #43 3–5 5/12/10 99.4 97.6 93.6 88.3 70.5 57.5 46.6 37.8 23.9

Core #43 15–18 5/12/10 82.6 4.7 1.0 -- -- -- -- -- --

Core #43 53–56 5/12/10 99.7 96.9 73.3 53.6 34.9 25.6 20.1 16.3 14.4

Core #43 120–123 5/12/10 93.9 60.1 46.4 39.8 32.2 25.5 20.5 16.8 14.9

Core #44 0–4 5/12/10 22.6 3.0 1.1 -- -- -- -- -- --

Core #46 50–53 5/13/10 97.2 16.6 6.0 -- -- -- -- -- --

Core #46 55–58 5/13/10 99.5 83.8 72.0 59.8 43.1 31.8 24.1 18.9 16.2

Core #46 80–83 5/13/10 98.4 46.8 32.2 28.6 23.0 18.6 14.4 11.5 8.2

Core #46 97–100 5/13/10 96.4 11.1 1.7 -- -- -- -- -- --

Core #47 5–8 5/13/10 88.9 12.2 3.6 -- -- -- -- -- --

Core #47 51–54 5/13/10 93.2 13.8 2.3 -- -- -- -- -- --

Core #47 109–112 5/13/10 81.4 9.2 1.7 -- -- -- -- -- --

Core #48 0–2 5/12/10 13.6 1.8 0.6 -- -- -- -- -- --

Core #49 2–5 5/14/10 98.2 7.1 0.8 -- -- -- -- -- --

Core #49 30–33 5/14/10 99.8 99.0 88.1 67.5 45.5 31.5 24.7 19.7 17.9

Core #49 86–89 5/14/10 98.7 80.0 22.4 14.2 10.3 8.0 5.9 4.8 3.4

Core #49 98–101 5/14/10 99.8 96.5 89.9 79.9 60.0 41.6 29.4 21.9 18.8

Core #49 128–131 5/14/10 99.2 60.1 12.6 -- -- -- -- -- --

Core #50 0–2 5/14/10 69.5 36.8 27.7 25.0 21.4 17.8 14.3 11.3 10.0

Core #50 20–23 5/14/10 46.1 1.4 0.4 -- -- -- -- -- --

Core #50 62–65 5/14/10 37.7 2.0 0.6 -- -- -- -- -- --

Core #52 0–14 5/14/10 -- -- 96.5 81.8 55.9 39.2 28.6 21.1 15.8

Core #52 16–19 5/14/10 -- -- 96.7 81.2 54.4 42.0 32.9 27.2 19.2

Core #52 54–57 5/14/10 -- -- 96.5 78.2 55.7 40.9 32.0 26.8 16.8

Core #52 104–107 5/14/10 -- -- 98.2 85.0 59.3 41.9 32.2 25.8 19.6

Core #53 0–2 5/12/10 84.8 52.4 39.1 33.6 26.2 20.4 15.9 12.2 7.0

Core #53 27–30 5/12/10 67.8 2.5 0.5 -- -- -- -- -- --

Core #53 63–66 5/12/10 49.0 5.7 2.8 -- -- -- -- -- --

Core #54 2–5 5/15/10 10.0 0.8 0.2 -- -- -- -- -- --

Core #54 73–75 5/15/10 29.5 23.3 16.3 14.4 12.0 9.4 7.5 6.1 3.8

Core #54 103–106 5/15/10 29.7 25.8 20.7 15.8 10.5 7.7 6.0 4.8 3.6

Core #56 0–5 5/15/10 78.7 42.4 34.0 32.7 26.5 20.7 15.9 12.1 7.1

Core #57 0–1 5/15/10 15.0 0.8 0.3 -- -- -- -- -- --
54 Grain-Size Distribution and Selected Major and Trace Element Concentrations in Bed-Sediment Cores

Appendix 2. Grain-size data from bed-sediment core samples collected in Lower Granite Reservoir and the Clearwater and Snake 

Rivers just above their confluence, 2010.—Continued

[# , number; cm, centimeter; mm, millimeter; --, not analyzed]

USGS station 

number

Core 

identifier

Core 

sample 

interval 

analyzed

(cm)

Sample 

identifier Date

Percent 

finer than 

16 mm; 

coarse/

medium 

pebbles

Percent 

finer than 

8 mm; 

medium/fine 

pebbles

Percent 

finer than 

4 mm; 

fine/

very fine 

pebbles

Percent 

finer than 

2 mm; 

very fine 

pebbles/

very coarse 

sand

Percent 

finer than 

1 mm; very 

coarse 

sand/

coarse 

sand

Percent 

finer than 

0.50 mm; 

coarse/

medium 

sand

Lower Granite Reservoir—Continued

462540117033500 59 0–3 Core #59 0–3 5/15/10 -- -- -- -- 100.0 99.7

462542117033601 60 0–2 Core #60 0–2 5/15/10 -- -- -- -- 100.0 93.3

462542117033601 60 6–9 Core #60 6–9 5/15/10 -- -- -- 100.0 99.9 99.1

462542117033601 60 50–53 Core #60 50–53 5/15/10 -- -- -- 100.0 99.9 99.3

462541117030300 62 84–87 Core #62 84–87 5/12/10 -- -- -- 100.0 99.9 99.6

462541117030300 62 94–97 Core #62 94–97 5/12/10 -- -- -- 100.0 99.9 99.2

462546117030500 63 0–2 Core #63 0–2 5/20/10 -- -- -- 100.0 98.3 92.3

462546117030500 63 10–13 Core #63 10–13 5/20/10 -- -- -- 100.0 99.7 83.7

462536117023500 65 60–63 Core #65 60–63 5/11/10 -- -- -- -- 100.0 99.2

462536117023500 65 65–68 Core #65 65–68 5/11/10 -- -- -- -- 100.0 99.4

462536117023500 65 85–88 Core #65 85–88 5/11/10 -- -- -- -- 100.0 98.3

462542117024801 66 0–1 Core #66 0–1 5/20/10 -- -- -- -- 100.0 99.7

462542117024801 66 10–13 Core #66 10–13 5/20/10 -- -- -- 100.0 99.9 97.7

Confluence

462535117020701 70 0–2 Core #70 0–2 5/14/10 -- -- -- -- 100.0 99.4

462535117020701 70 4–7 Core #70 4–7 5/14/10 -- -- -- 100.0 99.9 97.3

462535117020701 70 26–28 Core #70 26–28 5/14/10 -- -- -- -- 100.0 98.7

462535117020701 70 35–36 Core #70 35–36 5/14/10 -- -- -- -- 100.0 98.4

462535117020701 70 38–41 Core #70 38–41 5/14/10 -- -- -- 100.0 99.8 98.9

462535117020701 70 50–52 Core #70 50–52 5/14/10 -- -- 100.0 99.5 98.9 96.0

462537117020500 71 2–5 Core #71 2–5 5/14/10 -- -- -- 100.0 99.9 99.3

462537117020500 71 43–46 Core #71 43–46 5/14/10 -- -- -- -- 100.0 99.8

462537117020500 71 90–93 Core #71 90–93 5/14/10 -- -- -- -- -- --

462537117020500 71 135–137 Core #71 135–137 5/14/10 -- -- -- -- 100.0 99.4

462537117020500 71 144–146 Core #71 144–146 5/14/10 -- -- 100.0 99.3 99.1 98.7

Snake River

462522117021500 72 0–0.5 Core #72 0–0.5 5/19/10 -- -- -- 100.0 99.7 97.6

462522117021501 73 0–2 Core #73 0–2 5/19/10 -- -- -- -- 100.0 98.4

462440117021300 78 0–0.5 Core #78 0–0.5 5/19/10 -- -- -- -- 100.0 99.7

462437117020601 80 0–1 Core #80 0–1 5/19/10 -- -- -- -- 100.0 98.3

462426117021901 81 0–3 Core #81 0–3 5/19/10 -- -- -- 100.0 99.2 96.3

462426117021600 82 0–3 Core #82 0–3 10/13/10 -- 100.0 99.8 99.7 99.2 81.5

462413117022100 84 5–15 Core #84 5–15 10/13/10 -- -- -- 100.0 99.9 90.6

462413117022100 84 25–35 Core #84 25–35 10/13/10 -- 100.0 99.8 99.7 99.4 89.5
Appendix 2 55

Appendix 2. Grain-size data from bed-sediment core samples collected in Lower Granite Reservoir and the Clearwater and Snake 

Rivers just above their confluence, 2010.—Continued

[# , number; cm, centimeter; mm, millimeter; --, not analyzed]

Sample 

identifier Date

Percent 

finer than 

0.25 mm; 

medium/ 

fine sand

Percent 

finer than 

0.125 mm; 

fine/very 

fine sand

Percent 

finer than 

0.0625 mm; 

very fine 

sand/

coarse 

silt

Percent 

finer than 

0.031 mm; 

coarse/

medium 

silt

Percent 

finer than 

0.016 mm; 

medium/

fine silt

Percent 

finer than 

0.008 mm; 

fine/very 

fine silt

Percent 

finer than 

0.004 mm; 

very fine 

silt/clay

Percent 

finer than 

0.002 mm; 

silt/clay 

for mineral 

analysis

Percent 

finer than 

0.001 mm; 

finer than 

clay

Lower Granite Reservoir—Continued

Core #59 0–3 5/15/10 55.4 18.1 3.9 2.9 2.2 1.8 1.5 1.2 0.9

Core #60 0–2 5/15/10 80.4 67.0 36.7 33.0 27.1 22.2 18.4 15.5 10.9

Core #60 6–9 5/15/10 22.8 2.3 0.3 -- -- -- -- -- --

Core #60 50–53 5/15/10 23.2 1.5 0.4 -- -- -- -- -- --

Core #62 84–87 5/12/10 50.6 2.3 0.3 -- -- -- -- -- --

Core #62 94–97 5/12/10 74.0 3.5 1.0 -- -- -- -- -- --

Core #63 0–2 5/20/10 26.0 7.6 2.8 -- -- -- -- -- --

Core #63 10–13 5/20/10 5.9 0.7 0.1 -- -- -- -- -- --

Core #65 60–63 5/11/10 26.0 1.1 0.3 -- -- -- -- -- --

Core #65 65–68 5/11/10 43.6 1.6 0.3 -- -- -- -- -- --

Core #65 85–88 5/11/10 14.2 1.1 0.4 -- -- -- -- -- --

Core #66 0–1 5/20/10 96.7 90.8 71.7 58.4 44.6 34.8 28.0 24.2 21.7

Core #66 10–13 5/20/10 14.0 2.0 0.4 -- -- -- -- -- --

Confluence

Core #70 0–2 5/14/10 84.5 66.7 58.1 52.0 41.5 33.4 27.4 23.2 21.4

Core #70 4–7 5/14/10 44.1 3.6 1.0 -- -- -- -- -- --

Core #70 26–28 5/14/10 59.6 3.4 0.9 -- -- -- -- -- --

Core #70 35–36 5/14/10 74.7 31.9 28.1 26.5 23.6 20.0 16.5 14.0 12.8

Core #70 38–41 5/14/10 77.2 6.6 2.2 -- -- -- -- -- --

Core #70 50–52 5/14/10 45.0 6.8 2.6 -- -- -- -- -- --

Core #71 2–5 5/14/10 69.9 3.8 1.2 -- -- -- -- -- --

Core #71 43–46 5/14/10 98.1 89.6 81.6 67.1 45.7 34.6 28.0 23.8 19.6

Core #71 90–93 5/14/10 -- -- 95.1 76.0 49.1 36.9 29.9 25.2 20.5

Core #71 135–137 5/14/10 94.3 20.0 5.2 4.6 3.7 2.4 1.6 1.3 0.9

Core #71 144–146 5/14/10 97.9 93.5 71.1 52.9 36.2 27.9 21.8 17.4 14.2

Snake River

Core #72 0–0.5 5/19/10 16.2 1.0 0.1 -- -- -- -- -- --

Core #73 0–2 5/19/10 26.8 3.6 0.3 -- -- -- -- -- --

Core #78 0–0.5 5/19/10 48.3 3.1 0.2 -- -- -- -- -- --

Core #80 0–1 5/19/10 41.9 6.3 0.8 -- -- -- -- -- --

Core #81 0–3 5/19/10 26.5 1.5 0.2 -- -- -- -- -- --

Core #82 0–3 10/13/10 8.6 0.8 0.3 -- -- -- -- -- --

Core #84 5–15 10/13/10 8.5 1.0 0.4 -- -- -- -- -- --

Core #84 25–35 10/13/10 7.9 0.6 0.3 -- -- -- -- -- --
56 Grain-Size Distribution and Selected Major and Trace Element Concentrations in Bed-Sediment Cores

Appendix 2. Grain-size data from bed-sediment core samples collected in Lower Granite Reservoir and the Clearwater and Snake 

Rivers just above their confluence, 2010.—Continued

[# , number; cm, centimeter; mm, millimeter; --, not analyzed]

USGS station 

number

Core 

identifier

Core 

sample 

interval 

analyzed

(cm)

Sample 

identifier Date

Percent 

finer than 

16 mm; 

coarse/

medium 

pebbles

Percent 

finer than 

8 mm; 

medium/fine 

pebbles

Percent 

finer than 

4 mm; 

fine/

very fine 

pebbles

Percent 

finer than 

2 mm; 

very fine 

pebbles/

very coarse 

sand

Percent 

finer than 

1 mm; very 

coarse 

sand/

coarse 

sand

Percent 

finer than 

0.50 mm; 

coarse/

medium 

sand

Snake River—Continued

462413117022100 84 45–55 Core #84 45–55 10/13/10 -- -- -- 100.0 99.7 91.2

462413117022100 84 65–75 Core #84 65–75 10/13/10 -- -- 100.0 99.6 96.8 70.0

462413117022100 84 85–95 Core #84 85–95 10/13/10 -- -- -- 100.0 99.9 90.0

462413117021900 85 5–15 Core #85 5–15 10/13/10 -- -- -- 100.0 99.6 82.6

462413117021900 85 25–35 Core #85 25–35 10/13/10 -- 100.0 99.9 99.5 83.1 6.2

462413117021900 85 45–55 Core #85 45–55 10/13/10 -- -- -- 100.0 98.3 67.2

462413117021900 85 55–65 Core #85 55–65 10/13/10 -- -- 100.0 99.7 98.8 79.3

462348117022801 87 0–19 Core #87 0–19 5/19/10 -- -- -- 100.0 97.9 75.1

462348117022801 87 16–20 Core #87 16–20 10/13/10 -- 100.0 99.8 99.8 99.8 96.3

462348117022801 87 50–55 Core #87 50–55 10/13/10 -- -- -- 100.0 99.6 94.0

462348117022801 87 68–72 Core #87 68–72 10/13/10 -- -- -- -- -- --

462348117022801 87 77–82 Core #87 77–82 10/13/10 -- -- -- -- 100.0 99.5

462352117022101 88 0–3 Core #88 0–3 5/19/10 -- -- -- 100.0 99.9 97.8

462348117021701 89 0–3 Core #89 0–3 5/19/10 -- -- -- 100.0 99.9 99.0
Appendix 2 57

Appendix 2. Grain-size data from bed-sediment core samples collected in Lower Granite Reservoir and the Clearwater and Snake 

Rivers just above their confluence, 2010.—Continued

[# , number; cm, centimeter; mm, millimeter; --, not analyzed]

Sample 

identifier Date

Percent 

finer than 

0.25 mm; 

medium/ 

fine sand

Percent 

finer than 

0.125 mm; 

fine/very 

fine sand

Percent 

finer than 

0.0625 mm; 

very fine 

sand/

coarse 

silt

Percent 

finer than 

0.031 mm; 

coarse/

medium 

silt

Percent 

finer than 

0.016 mm; 

medium/

fine silt

Percent 

finer than 

0.008 mm; 

fine/very 

fine silt

Percent 

finer than 

0.004 mm; 

very fine 

silt/clay

Percent 

finer than 

0.002 mm; 

silt/clay 

for mineral 

analysis

Percent 

finer than 

0.001 mm; 

finer than 

clay

Snake River—Continued

Core #84 45–55 10/13/10 6.8 0.7 0.3 -- -- -- -- -- --

Core #84 65–75 10/13/10 4.0 0.7 0.4 -- -- -- -- -- --

Core #84 85–95 10/13/10 5.9 0.7 0.3 -- -- -- -- -- --

Core #85 5–15 10/13/10 2.8 0.3 0.2 -- -- -- -- -- --

Core #85 25–35 10/13/10 0.7 0.2 0.2 -- -- -- -- -- --

Core #85 45–55 10/13/10 1.7 0.3 0.2 -- -- -- -- -- --

Core #85 55–65 10/13/10 6.2 0.8 0.2 -- -- -- -- -- --

Core #87 0–19 5/19/10 13.4 4.3 0.6 -- -- -- -- -- --

Core #87 16–20 10/13/10 17.3 0.8 0.2 -- -- -- -- -- --

Core #87 50–55 10/13/10 53.5 40.5 35.4 32.5 24.4 16.9 12.3 9.8 8.1

Core #87 68–72 10/13/10 -- 100.0 94.0 85.0 62.2 43.5 32.3 25.5 17.7

Core #87 77–82 10/13/10 91.2 52.4 21.7 18.4 14.8 12.6 10.7 9.0 7.6

Core #88 0–3 5/19/10 73.7 7.9 0.5 -- -- -- -- -- --

Core #89 0–3 5/19/10 57.8 13.6 1.1 -- -- -- -- -- --

Appendix 3—Analytical Data for Major and Trace Elements in 

Bed-Sediment Core Samples

Appendix 3
60 Grain-Size Distribution and Selected Major and Trace Element Concentrations in Bed-Sediment Cores

Appendix 3. Analytical data for major and trace elements in bed-sediment core samples collected in Lower Granite Reservoir and the 

Clearwater and Snake Rivers just above their confluence, 2010.—Continued

[Concentrations in micrograms per gram unless otherwise noted; #, number; <, less than lower reporting limit]

USGS station 

number

Sample 

identifier Date Set number Calcium Magnesium

Potassium Sodium

Total 

carbon

(percent)

Inorganic 

carbon

(percent)

PhosphorusAluminum

Clearwater River

462532117011101 Core #9 18–21 5/13/2010 11150 21,800 10,600 13,300 16,100 1.92 0.02 950 80,400

462532117011101 Core #9 34–37 5/13/2010 11150 24,200 10,700 15,100 20,600 1.02 0.01 818 74,500

462532117011101 Core #9 50–53 5/13/2010 11150 20,200 9,920 13,400 15,600 2.84 0.01 956 80,100

Lower Granite Reservoir

463216117150001 Core #31 0–3 4/6/2010 11150 22,400 10,200 16,500 15,700 6.02 0.04 1,090 67,900

463216117150001 Core #31 14–17 4/6/2010 11150 22,600 10,700 19,700 18,900 3.76 0.03 1,020 73,900

463216117150001 Core #31 28–31 4/6/2010 11150 21,400 11,100 19,000 14,400 6.55 0.06 1,230 74,200

463216117150001 Core #31 42–45 4/6/2010 11150 22,900 11,300 16,300 13,700 7.62 0.05 1,320 68,300

463216117150001 Core #31 56–59 4/6/2010 11150 23,700 11,700 14,600 13,700 7.90 0.06 1,420 66,300

463216117150001 Core #31 70–73 4/6/2010 11150 22,800 11,900 18,900 16,000 5.07 0.05 1,060 69,300

463216117150001 Core #31 84–87 4/6/2010 11150 24,100 12,300 18,000 14,900 6.82 0.09 1,260 70,700

463216117150001 Core #31 98–101 4/6/2010 11150 25,700 12,000 17,900 18,200 4.44 0.04 1,060 72,300

463216117150001 Core #31 112–115 4/6/2010 11150 22,900 11,500 17,100 15,900 5.00 0.04 1,120 70,700

463216117150001 Core #31 126–129 4/6/2010 11150 25,300 12,600 16,900 16,300 4.88 0.05 1,180 72,500

463216117150001 Core #31 140–143 4/6/2010 11150 22,600 11,400 16,400 14,100 6.28 0.05 1,250 70,500

463216117150001 Core #31 154–157 4/6/2010 11150 25,400 11,400 16,500 17,100 4.15 0.03 1,090 72,400

463216117150001 Core #31 164–167 4/6/2010 11150 27,800 12,700 16,600 18,800 2.78 0.04 1,020 74,800

462520117122001 Core #38 7–10 5/12/2010 11150 26,200 10,700 18,500 20,100 2.04 0.01 864 70,400

462520117122001 Core #38 12–15 5/12/2010 11150 22,600 10,200 13,800 13,600 6.11 0.04 1,340 64,900

462520117122001 Core #38 60–63 5/12/2010 11150 21,900 10,600 20,100 23,500 0.22 0.01 611 74,300

462520117122001 Core #38 98–101 5/12/2010 11150 25,000 11,300 19,500 24,100 0.17 0.02 722 76,200

462520117122001 Core #38 105–108 5/12/2010 11150 30,500 12,300 12,800 17,100 3.29 0.07 1,070 72,900

462520117122001 Core #38 155–158 5/12/2010 11150 25,900 11,000 12,300 14,700 3.65 0.07 1,180 71,700

462515117065401 Core #47 5–8 5/13/2010 11150 18,900 8,340 22,500 22,600 4.43 0.02 561 72,100

462515117065401 Core #47 51–54 5/13/2010 11150 18,900 9,030 23,000 24,500 0.94 0.02 529 78,200

462515117065401 Core #47 109–112 5/13/2010 11150 22,600 9,880 19,900 24,800 0.16 0.01 602 74,600

462542117033601 Core #60 0–2 5/15/2010 11150 18,600 7,280 13,400 11,400 17.10 0.06 831 45,500

462542117033601 Core #60 6–9 5/15/2010 11150 18,600 6,120 23,300 22,900 0.12 <0.01 432 66,400

462542117033601 Core #60 50–53 5/15/2010 11150 26,300 9,640 18,900 21,900 0.12 0.01 521 65,600

462542117024801 Core #66 10–13 5/20/2010 11150 19,600 6,540 21,300 22,400 0.14 <0.01 413 64,900

Appendix 3. Analytical data for major and trace elements in bed-sediment core samples collected in Lower Granite Reservoir and the 

Clearwater and Snake Rivers just above their confluence, 2010.

[Concentrations in micrograms per gram unless otherwise noted; #, number; <, less than lower reporting limit]
Appendix 3 61

Appendix 3. Analytical data for major and trace elements in bed-sediment core samples collected in Lower Granite Reservoir and the 

Clearwater and Snake Rivers just above their confluence, 2010.—Continued

[Concentrations in micrograms per gram unless otherwise noted; #, number; <, less than lower reporting limit]

USGS station 

number

Sample 

identifier Date Set number Calcium Magnesium

Potassium Sodium

Total 

carbon

(percent)

Inorganic 

carbon

(percent)

PhosphorusAluminum

Confluence

462535117020701 Core #70 0–2 5/14/2010 11150 17,400 8,470 14,900 15,900 5.69 0.03 1,040 71,300

462535117020701 Core #70 4–7 5/14/2010 11150 18,900 6,810 20,400 23,700 0.21 <0.01 420 71,700

462535117020701 Core #70 26–28 5/14/2010 11150 21,400 8,260 19,300 23,400 0.18 <0.01 474 73,200

462535117020701 Core #70 35–36 5/14/2010 11150 17,300 8,270 13,700 14,900 5.64 0.04 1,080 68,600

462535117020701 Core #70 38–41 5/14/2010 11150 22,200 8,960 19,200 23,900 0.42 <0.01 544 76,900

462535117020701 Core #70 50–52 5/14/2010 11150 19,100 8,130 20,000 22,900 0.74 <0.01 514 75,600

Snake River

462522117021501 Core #73 0–2 5/19/2010 11150 19,500 7,410 20,700 23,500 0.14 <0.01 440 69,000

462437117020601 Core #80 0–1 5/19/2010 11150 20,500 8,720 20,800 23,700 0.26 0.01 529 70,500

462426117021901 Core #81 0–3 5/19/2010 11150 17,500 6,840 23,200 23,000 0.13 <0.01 384 70,700

462413117022101 Core #84 5–15 10/13/2010 11637 20,200 7,600 19,300 21,000 0.11 <0.01 471 61,200

462413117022101 Core #84 25–35 10/13/2010 11637 18,700 7,140 18,600 20,100 0.11 <0.01 468 59,300

462413117022101 Core #84 45–55 10/13/2010 11637 19,400 7,060 21,000 22,100 0.10 <0.01 453 65,500

462413117022101 Core #84 65–75 10/13/2010 11637 15,000 6,690 21,900 19,500 0.12 0.01 400 60,300

462413117022101 Core #84 85–95 10/13/2010 11637 15,900 5,890 19,500 19,600 0.11 0.01 402 57,700

462412117021801 Core #85 5–15 10/13/2010 11637 17,500 6,120 19,900 20,000 0.17 0.01 397 58,200

462412117021801 Core #85 25–35 10/13/2010 11637 18,300 6,740 18,000 19,400 0.12 <0.01 438 56,400

462412117021801 Core #85 45–55 10/13/2010 11637 21,800 8,770 18,600 20,500 0.12 <0.01 506 61,300

462412117021801 Core #85 55–65 10/13/2010 11637 19,300 7,180 18,600 20,000 0.11 <0.01 477 58,800

462348117022801 Core #87 0–19 5/19/2010 11150 18,500 7,330 19,400 21,400 0.59 0.01 472 63,700

462352117022101 Core #88 0–3 5/19/2010 11150 19,400 7,770 23,500 24,600 0.16 0.01 520 75,200

462348117021701 Core #89 0–3 5/19/2010 11150 19,200 7,640 23,900 24,000 0.17 0.01 499 72,800
62 Grain-Size Distribution and Selected Major and Trace Element Concentrations in Bed-Sediment Cores

Appendix 3. Analytical data for major and trace elements in bed-sediment core samples collected in Lower Granite Reservoir and the 

Clearwater and Snake Rivers just above their confluence, 2010.—Continued

[Concentrations in micrograms per gram unless otherwise noted; #, number; <, less than lower reporting limit]

Sample 

identifier Date Barium Beryllium

BismuthCadmium Cerium Cesium Chromium Cobalt Copper Gallium Iron

Clearwater River

Core #9 18–21 5/13/2010 684 1.7 5.48 0.18 64.4 2.7 46.7 25.2 33.5 20.0 54,000

Core #9 34–37 5/13/2010 735 1.2 4.78 0.12 48.0 1.8 35.4 17.4 740 17.3 40,600

Core #9 50–53 5/13/2010 676 1.5 5.63 0.21 67.3 3.1 44.8 23.3 38.2 19.9 52,800

Lower Granite Reservoir

Core #31 0–3 4/6/2010 673 1.8 6.70 0.34 60.9 4.2 42.1 18.1 33.1 19.4 40,900

Core #31 14–17 4/6/2010 765 2.0 6.80 0.29 68.2 4.1 48.7 17.3 30.2 20.1 38,400

Core #31 28–31 4/6/2010 689 2.6 9.61 0.41 91.1 6.8 46.4 23.7 46.9 22.5 43,500

Core #31 42–45 4/6/2010 664 2.1 8.50 0.46 75.4 5.2 49.1 22.2 43.4 21.0 44,500

Core #31 56–59 4/6/2010 644 2.1 7.70 0.42 71.1 4.6 44.9 23.2 46.1 19.9 47,100

Core #31 70–73 4/6/2010 775 2.1 14.3 0.37 76.8 5.3 52.9 18.9 38.6 20.6 40,800

Core #31 84–87 4/6/2010 684 2.2 9.01 0.45 83.3 5.6 53.6 21.4 44.5 21.2 44,900

Core #31 98–101 4/6/2010 714 1.7 6.49 0.32 65.5 4.3 52.9 21.2 36.7 19.8 42,000

Core #31 112–115 4/6/2010 667 1.8 7.08 0.41 69.9 4.7 51.8 19.6 39.9 20.1 42,300

Core #31 126–129 4/6/2010 688 1.9 7.38 0.37 65.7 4.6 54.1 22.8 44.8 20.8 45,600

Core #31 140–143 4/6/2010 655 2.2 8.81 0.42 74.3 5.4 51.0 22.8 44.6 20.7 44,400

Core #31 154–157 4/6/2010 697 1.7 6.64 0.36 59.2 3.9 51.7 22.4 36.2 19.7 42,900

Core #31 164–167 4/6/2010 723 1.5 5.90 0.27 58.1 3.2 52.4 20.9 36.7 19.8 45,000

Core #38 7–10 5/12/2010 762 1.6 5.21 0.19 60.3 2.7 48.1 16.9 24.5 18.7 37,400

Core #38 12–15 5/12/2010 619 1.8 6.41 0.34 56.4 4.0 44.9 20.0 35.0 18.5 41,800

Core #38 60–63 5/12/2010 822 1.6 4.62 0.10 46.8 2.2 43.8 15.7 18.5 17.3 32,400

Core #38 98–101 5/12/2010 804 1.7 4.56 0.11 56.6 2.1 49.0 16.3 18.2 17.7 33,400

Core #38 105–108 5/12/2010 674 1.4 4.66 0.24 52.9 2.5 38.5 27.6 42.5 20.1 63,400

Core #38 155–158 5/12/2010 679 1.4 5.10 0.25 63.7 2.8 42.4 26.4 39.2 20.3 58,600

Core #47 5–8 5/13/2010 868 2.0 5.02 0.17 41.2 2.7 34.3 12.8 17.1 17.2 26,800

Core #47 51–54 5/13/2010 869 1.7 4.82 0.09 43.2 2.8 35.7 12.1 17.0 17.6 26,800

Core #47 109–112 5/13/2010 824 1.6 4.51 0.09 39.6 2.0 40.6 13.5 16.0 16.9 29,500

Core #60 0–2 5/15/2010 547 1.7 5.07 0.32 43.1 2.9 31.6 13.6 41.2 13.3 27,200

Core #60 6–9 5/15/2010 886 1.5 4.57 0.06 31.7 1.9 27.2 9.9 13.0 15.8 19,900

Core #60 50–53 5/15/2010 771 1.3 4.17 0.09 62.0 1.5 56.4 13.6 16.7 16.5 34,000

Core #66 10–13 5/20/2010 838 1.4 4.38 0.06 38.5 1.6 28.0 10.0 13.4 15.5 21,200
Appendix 3 63

Appendix 3. Analytical data for major and trace elements in bed-sediment core samples collected in Lower Granite Reservoir and the 

Clearwater and Snake Rivers just above their confluence, 2010.—Continued

[Concentrations in micrograms per gram unless otherwise noted; #, number; <, less than lower reporting limit]

Sample 

identifier Date Barium Beryllium

BismuthCadmium Cerium Cesium Chromium Cobalt Copper Gallium Iron

Confluence

Core #70 0–2 5/14/2010 700 1.5 5.60 0.18 48.5 2.9 40.4 14.6 39.6 17.4 37,800

Core #70 4–7 5/14/2010 891 1.3 5.08 0.06 36.7 1.5 23.3 8.7 10.7 15.8 22,400

Core #70 26–28 5/14/2010 853 1.4 4.94 0.06 43.4 1.5 28.8 9.9 12.3 16.4 27,100

Core #70 35–36 5/14/2010 666 1.5 5.27 0.20 50.7 2.4 41.9 16.5 27.4 17.0 36,500

Core #70 38–41 5/14/2010 848 1.4 5.05 0.07 37.3 1.7 32.4 11.8 12.9 17.1 30,100

Core #70 50–52 5/14/2010 886 1.4 4.96 0.08 32.7 1.8 26.5 12.2 33.8 16.7 29,800

Snake River

Core #73 0–2 5/19/2010 839 1.6 4.24 0.07 36.3 1.7 31.9 9.5 11.4 15.3 21,300

Core #80 0–1 5/19/2010 828 1.4 4.38 0.09 55.6 1.8 39.9 11.1 12.4 16.2 25,400

Core #81 0–3 5/19/2010 920 1.6 4.64 0.07 51.7 2.0 35.1 11.1 12.6 16.5 27,200

Core #84 5–15 10/13/2010 943 1.5 4.11 0.08 30.9 1.6 28.7 11.1 14.8 15.2 24,300

Core #84 25–35 10/13/2010 910 1.6 4.34 0.06 32.3 1.6 27.1 10.3 15.4 14.5 23,100

Core #84 45–55 10/13/2010 1,040 1.8 4.50 0.07 29.4 1.9 24.6 10.8 14.4 16.0 22,600

Core #84 65–75 10/13/2010 1,040 1.8 10.4 0.02 34.7 2.5 22.9 11.1 18.9 16.3 22,300

Core #84 85–95 10/13/2010 1,000 1.7 4.38 0.06 30.1 1.9 20.3 9.7 74.6 14.5 19,500

Core #85 5–15 10/13/2010 936 1.3 5.06 0.07 31.2 1.7 23.1 9.2 12.4 14.4 20,000

Core #85 25–35 10/13/2010 855 1.4 4.03 0.06 39.2 1.6 20.1 10.0 13.2 13.9 22,700

Core #85 45–55 10/13/2010 923 1.5 4.40 0.09 31.0 1.6 31.0 12.3 17.2 15.2 27,500

Core #85 55–65 10/13/2010 886 1.5 4.02 0.07 35.4 1.6 25.0 10.4 14.9 14.6 23,900

Core #87 0–19 5/19/2010 776 1.3 4.08 0.07 34.8 1.6 26.6 10.8 17.7 14.7 24,000

Core #88 0–3 5/19/2010 879 1.8 4.80 0.08 56.2 2.3 36.2 10.4 12.7 17.4 25,100

Core #89 0–3 5/19/2010 883 1.6 4.81 0.08 43.5 2.3 35.7 10.4 12.4 17.1 24,500
64 Grain-Size Distribution and Selected Major and Trace Element Concentrations in Bed-Sediment Cores

Appendix 3. Analytical data for major and trace elements in bed-sediment core samples collected in Lower Granite Reservoir and the 

Clearwater and Snake Rivers just above their confluence, 2010.—Continued

[Concentrations in micrograms per gram unless otherwise noted; #, number; <, less than lower reporting limit]

Sample 

identifier Date Lanthanum

Lead Lithium Manganese Mercury Molybdenum Nickel Niobium Rubidium Scandium

Clearwater River

Core #9 18–21 5/13/2010 31.8 14.5 20.7 970 0.03 0.76 23.4 13 62.9 20.2

Core #9 34–37 5/13/2010 24.5 12.5 14.8 746 0.02 0.55 17.0 10 56.1 15.1

Core #9 50–53 5/13/2010 33.3 14.6 22.2 998 0.03 0.80 22.1 13 65.7 19.9

Lower Granite Reservoir

Core #31 0–3 4/6/2010 32.8 17.5 26.8 817 0.08 1.2 20.2 14 80.0 15.3

Core #31 14–17 4/6/2010 36.2 17.4 25.4 735 0.08 1.1 20.9 15 90.4 14.1

Core #31 28–31 4/6/2010 49.4 24.3 33.2 1,090 0.14 1.6 22.0 18 101.0 15.2

Core #31 42–45 4/6/2010 38.9 21.7 32.5 1,160 0.28 1.8 24.0 16 83.9 16.1

Core #31 56–59 4/6/2010 38.2 19.9 27.2 1,110 0.14 1.5 23.8 14 74.5 17.6

Core #31 70–73 4/6/2010 40.6 38.7 27.4 852 0.20 2.1 27.4 17 92.7 14.7

Core #31 84–87 4/6/2010 43.6 23.7 29.2 1,100 0.24 1.9 28.2 18 90.6 16.0

Core #31 98–101 4/6/2010 34.4 16.9 24.2 853 0.08 1.2 25.4 17 85.4 15.4

Core #31 112–115 4/6/2010 36.4 18.4 26.6 787 0.09 1.9 25.9 16 86.2 15.7

Core #31 126–129 4/6/2010 34.9 19.4 26.8 964 0.15 2.8 27.5 16 81.7 16.9

Core #31 140–143 4/6/2010 39.7 22.6 28.7 984 0.14 3.4 25.5 16 84.5 16.2

Core #31 154–157 4/6/2010 31.6 17.5 24.5 783 0.09 2.1 24.0 14 75.6 16.2

Core #31 164–167 4/6/2010 30.0 15.5 20.7 790 0.09 0.86 26.2 14 70.8 17.5

Core #38 7–10 5/12/2010 31.9 13.9 19.1 694 0.05 0.69 19.9 13 75.1 14.6

Core #38 12–15 5/12/2010 30.5 16.8 23.6 930 0.08 1.0 22.5 12 67.5 16.2

Core #38 60–63 5/12/2010 24.7 12.4 17.5 532 0.02 1.3 18.1 12 76.1 12.1

Core #38 98–101 5/12/2010 31.0 12.0 15.9 571 0.02 0.58 17.3 13 71.1 13.5

Core #38 105–108 5/12/2010 25.8 12.3 17.8 1,230 0.04 1.0 21.8 12 57.4 23.5

Core #38 155–158 5/12/2010 31.3 13.6 20.6 1,220 0.04 0.96 22.4 13 61.0 22.9

Core #47 5–8 5/13/2010 22.9 13.5 20.0 482 0.03 0.88 15.1 12 88.6 9.1

Core #47 51–54 5/13/2010 22.9 12.9 21.0 437 0.02 0.47 14.9 13 93.7 9.3

Core #47 109–112 5/13/2010 20.6 12.1 14.9 509 0.04 0.51 16.8 11 72.4 11.6

Core #60 0–2 5/15/2010 24.5 13.5 18.2 798 0.07 1.3 17.2 10 64.0 8.3

Core #60 6–9 5/15/2010 17.0 12.4 13.2 349 0.01 0.42 11.8 9.2 84.7 7.6

Core #60 50–53 5/15/2010 33.4 11.1 11.7 753 0.26 0.64 17.6 16 65.8 13.7

Core #66 10–13 5/20/2010 20.1 11.7 12.1 394 0.02 0.54 12.8 8.8 76.0 8.4
Appendix 3 65

Appendix 3. Analytical data for major and trace elements in bed-sediment core samples collected in Lower Granite Reservoir and the 

Clearwater and Snake Rivers just above their confluence, 2010.—Continued

[Concentrations in micrograms per gram unless otherwise noted; #, number; <, less than lower reporting limit]

Sample 

identifier Date Lanthanum

Lead Lithium Manganese Mercury Molybdenum Nickel Niobium Rubidium Scandium

Confluence

Core #70 0–2 5/14/2010 27.2 14.5 21.5 673 0.05 0.63 20.1 10 69.3 13.1

Core #70 4–7 5/14/2010 19.9 13.6 13.1 346 0.01 0.31 10.0 7.0 66.9 8.1

Core #70 26–28 5/14/2010 23.0 13.1 13.0 437 0.01 0.32 11.5 9.5 64.4 9.8

Core #70 35–36 5/14/2010 27.3 14.1 20.0 734 0.06 0.76 21.1 8.7 58.1 13.4

Core #70 38–41 5/14/2010 19.3 13.0 14.1 480 0.01 0.37 13.0 8.5 65.6 11.0

Core #70 50–52 5/14/2010 17.7 12.9 15.0 478 0.01 0.35 12.6 7.9 70.8 9.9

Snake River

Core #73 0–2 5/19/2010 18.4 11.7 13.3 411 0.01 0.46 12.7 8.2 72.4 8.8

Core #80 0–1 5/19/2010 30.6 11.7 14.0 553 0.02 0.56 15.2 11 75.7 10.6

Core #81 0–3 5/19/2010 28.6 12.2 15.0 574 2.32 0.50 12.9 15 85.3 8.5

Core #84 5–15 10/13/2010 15.9 11.3 13.7 491 0.01 0.44 12.4 9.7 71.7 9.7

Core #84 25–35 10/13/2010 16.6 11.8 13.4 418 0.01 0.43 11.7 8.5 69.9 8.9

Core #84 45–55 10/13/2010 15.6 12.3 15.6 394 0.03 0.44 11.7 8.8 80.2 8.7

Core #84 65–75 10/13/2010 18.8 28.6 20.8 389 0.02 0.47 12.7 12 92.3 7.6

Core #84 85–95 10/13/2010 15.8 11.8 14.4 346 0.01 0.40 10.0 8.7 79.5 7.2

Core #85 5–15 10/13/2010 16.7 13.7 11.8 368 0.01 0.42 10.6 8.7 76.2 7.5

Core #85 25–35 10/13/2010 21.4 11.1 11.4 410 0.01 0.44 10.0 7.8 68 8.7

Core #85 45–55 10/13/2010 15.8 12.0 12.5 535 0.15 0.50 13.1 8.2 69.1 11.4

Core #85 55–65 10/13/2010 19.0 11.0 12.4 439 0.01 0.53 11.2 8.3 70.3 9.3

Core #87 0–19 5/19/2010 18.7 10.9 12.6 470 0.01 0.49 12.5 8.2 71.3 9.5

Core #88 0–3 5/19/2010 30.4 13.0 17.1 562 0.02 0.45 13.8 12 90.4 9.0

Core #89 0–3 5/19/2010 24.8 12.9 15.7 500 0.02 0.44 14.4 13 90.3 8.9
66 Grain-Size Distribution and Selected Major and Trace Element Concentrations in Bed-Sediment Cores

Appendix 3. Analytical data for major and trace elements in bed-sediment core samples collected in Lower Granite Reservoir and the 

Clearwater and Snake Rivers just above their confluence, 2010.—Continued

[Concentrations in micrograms per gram unless otherwise noted; #, number; <, less than lower reporting limit]

Sample 

identifier Date Silver Strontium

ThalliumTitaniumVanadium Yttrium Zinc Antimony

Arsenic

Organic 

carbon, 

percent

Thorium Uranium

Clearwater River

Core #9 18–21 5/13/2010 <0.01 281 0.38 7,760 201 27.6 98.2 0.39 3.2 1.90 7.95 2.29

Core #9 34–37 5/13/2010 <0.01 355 0.31 5,720 146 19.9 390 0.23 2.1 1.01 5.71 1.60

Core #9 50–53 5/13/2010 <0.01 265 0.40 7,280 191 28.7 99.3 0.45 3.8 2.83 8.45 2.46

Lower Granite Reservoir

Core #31 0–3 4/6/2010 <0.01 295 0.45 4,990 130 27.8 107 1.0 9.7 5.98 8.71 5.57

Core #31 14–17 4/6/2010 <0.01 333 0.47 4,750 122 24.6 113 1.1 8.8 3.73 9.76 4.65

Core #31 28–31 4/6/2010 0.094 278 0.54 4,630 122 36.0 117 1.5 23.5 6.49 13.2 17.0

Core #31 42–45 4/6/2010 0.099 286 0.49 5,040 135 32.2 119 1.9 18.1 7.57 10.4 15.5

Core #31 56–59 4/6/2010 0.020 283 0.44 5,450 150 33.5 116 1.1 13.3 7.84 9.88 12.9

Core #31 70–73 4/6/2010 0.095 297 0.52 4,620 124 29.4 108 1.7 10.6 5.02 11.6 11.7

Core #31 84–87 4/6/2010 0.037 291 0.50 5,110 134 33.1 117 1.5 11.6 6.73 12.7 14.1

Core #31 98–101 4/6/2010 <0.01 328 0.47 5,210 131 26.9 103 0.81 7.5 4.40 10.7 4.93

Core #31 112–115 4/6/2010 <0.01 295 0.48 5,100 129 29.7 109 0.85 8.6 4.96 11.2 6.11

Core #31 126–129 4/6/2010 <0.01 310 0.46 5,480 147 29.2 111 1.8 11.1 4.83 9.82 11.1

Core #31 140–143 4/6/2010 <0.01 274 0.48 5,180 136 32.4 117 1.2 12.1 6.23 11.2 12.8

Core #31 154–157 4/6/2010 <0.01 318 0.42 5,470 141 26.1 107 0.80 8.7 4.12 8.58 6.04

Core #31 164–167 4/6/2010 <0.01 349 0.40 6,170 160 25.2 102 0.81 6.1 2.74 7.62 3.73

Core #38 7–10 5/12/2010 <0.01 365 0.40 5,150 134 21.7 85.2 0.59 4.2 2.03 8.57 3.22

Core #38 12–15 5/12/2010 0.033 272 0.40 4,980 136 29.3 108 0.77 7.4 6.07 7.83 5.86

Core #38 60–63 5/12/2010 <0.01 383 0.40 4,540 117 15.6 68.9 0.77 2.7 0.21 6.38 1.54

Core #38 98–101 5/12/2010 <0.01 390 0.38 5,000 130 17.5 69.5 0.70 2.6 0.15 7.07 1.56

Core #38 105–108 5/12/2010 <0.01 309 0.36 8,320 241 32.1 113 0.45 3.5 3.22 6.36 2.45

Core #38 155–158 5/12/2010 <0.01 277 0.38 8,030 225 32.6 115 0.46 3.9 3.58 6.96 2.81

Core #47 5–8 5/13/2010 <0.01 369 0.45 3,250 83.1 15.6 63.1 0.66 4.1 4.41 6.06 3.47

Core #47 51–54 5/13/2010 <0.01 381 0.46 3,290 81.8 13.6 61.9 0.46 3.0 0.92 6.42 2.37

Core #47 109–112 5/13/2010 <0.01 396 0.37 4,060 109 14.7 62.8 0.53 2.5 0.15 5.76 1.49

Core #60 0–2 5/15/2010 <0.01 239 0.35 2,560 80.8 20.3 79.5 1.1 9.0 17.04 5.34 8.17

Core #60 6–9 5/15/2010 <0.01 395 0.41 2,320 70.2 10.7 46.1 0.40 2.4 0.12 5.05 1.17

Core #60 50–53 5/15/2010 <0.01 394 0.33 5,720 141 19.2 61.4 0.47 2.7 0.11 7.41 1.59

Core #66 10–13 5/20/2010 <0.01 371 0.39 2,730 78.3 11.5 45.2 0.56 2.5 0.14 5.13 1.29
Appendix 3 67

Appendix 3. Analytical data for major and trace elements in bed-sediment core samples collected in Lower Granite Reservoir and the 

Clearwater and Snake Rivers just above their confluence, 2010.—Continued

[Concentrations in micrograms per gram unless otherwise noted; #, number; <, less than lower reporting limit]

Sample 

identifier Date Silver Strontium

ThalliumTitaniumVanadium Yttrium Zinc Antimony

Arsenic

Organic 

carbon, 

percent

Thorium Uranium

Confluence

Core #70 0–2 5/14/2010 <0.01 302 0.39 4,500 112 22.2 92.5 0.38 4.1 5.66 5.72 3.28

Core #70 4–7 5/14/2010 <0.01 414 0.35 2,720 72.1 9.8 47.4 0.10 1.1 0.21 4.96 0.98

Core #70 26–28 5/14/2010 <0.01 423 0.32 3,910 89.7 13.6 54.6 0.20 1.0 0.18 5.34 1.20

Core #70 35–36 5/14/2010 <0.01 277 0.35 4,280 114 22.7 83.2 0.36 5.0 5.60 5.49 3.42

Core #70 38–41 5/14/2010 <0.01 420 0.33 3,910 101 13.0 64.6 0.10 1.5 0.42 4.63 1.41

Core #70 50–52 5/14/2010 <0.01 405 0.36 3,580 93.6 12.8 69.3 0.20 1.6 0.74 3.79 1.26

Snake River

Core #73 0–2 5/19/2010 <0.01 373 0.36 2,700 76.4 11.3 44.2 0.36 2.4 0.14 6.69 1.36

Core #80 0–1 5/19/2010 <0.01 370 0.38 3,420 92.6 14.7 50.8 0.42 2.2 0.25 7.57 1.36

Core #81 0–3 5/19/2010 <0.01 372 0.42 3,970 98.7 14.1 53.2 0.40 2.3 0.13 7.82 1.42

Core #84 5–15 10/13/2010 0.039 361 0.35 3,190 88.5 14.0 49.0 0.10 2.2 0.11 4.22 1.10

Core #84 25–35 10/13/2010 0.030 344 0.36 3,010 86.0 13.0 49.1 0.22 2.5 0.11 4.63 1.17

Core #84 45–55 10/13/2010 0.031 388 0.41 2,850 80.9 12.7 47.5 0.20 2.8 0.10 4.73 1.21

Core #84 65–75 10/13/2010 0.029 324 0.47 2,640 71.4 13.1 54.0 0.38 3.1 0.11 5.88 1.59

Core #84 85–95 10/13/2010 0.069 342 0.40 2,470 69.5 11.9 72.4 0.22 2.3 0.10 4.76 1.21

Core #85 5–15 10/13/2010 0.075 341 0.39 2,500 70.9 11.6 45.2 0.75 2.4 0.16 4.80 1.13

Core #85 25–35 10/13/2010 0.035 323 0.35 2,830 82.5 12.9 47.5 0.28 2.5 0.12 5.95 1.11

Core #85 45–55 10/13/2010 0.027 348 0.35 3,470 105 15.1 54.7 0.25 2.5 0.12 4.38 1.21

Core #85 55–65 10/13/2010 0.026 329 0.34 3,020 87.4 13.3 48.6 0.20 2.4 0.11 5.42 1.17

Core #87 0–19 5/19/2010 <0.01 327 0.37 3,030 88.1 12.5 51.2 0.66 2.7 0.58 5.17 1.26

Core #88 0–3 5/19/2010 <0.01 380 0.44 3,410 84.7 14.6 72.5 0.47 2.9 0.15 7.65 1.44

Core #89 0–3 5/19/2010 <0.01 379 0.45 3,370 81.8 13.1 53.4 0.44 2.2 0.16 6.42 1.43

Appendix 4—Quality-Assurance and Quality-Control Data for 

Major and Trace Elements in Bed-Sediment Core Samples

Appendix 4
70 Grain-Size Distribution and Selected Major and Trace Element Concentrations in Bed-Sediment Cores

Appendix 4. Quality-assurance and quality-control data for major and trace elements in bed-sediment core samples collected in 

Lower Granite Reservoir and the Clearwater and Snake Rivers just above their confluence, 2010.—Continued

[Concentrations in micrograms per gram unless otherwise noted; #, number; <, less than lower reporting limit; %, percent; NIST, National Institute of Standards 

and Technology; --, not analyzed]

Type of qualitycontrol sampleSample 

identifier

Set 

number Calcium Magnesium Potassium Sodium Phosphorus

Aluminum

Environmental Core #31 164–167 11150 27,800 12,700 16,600 18,800 1,020 74,800

Laboratory replicate Core #31 164–167 replicate 11150 27,400 12,600 16,200 18,600 1,010 75,000

Laboratory replicate Core #31 164–167 replicate 11150 27,500 12,600 16,500 18,900 1,040 73,700

Blank Blank 11150 <100 <6 <15 <25 <5 <50

Blank Blank 11150 <100 <6 <15 44.2 <5 <50

Blank Blank 11150 <100 <6 <15 <25 <5 <50

Blank Blank 11150 <100 <6 <15 <25 <5 <50

Blank Blank 11150 <100 <6 <15 <25 <5 <50

Blank Blank 11150 <100 <6 <15 <25 <5 <50

Standard reference material MAG-1 found 11150 10,600 17,900 30,900 28,100 693 84,200

Standard reference material MAG-1 true 

(Potts and others, 1992)

11150 9,790 18,090 29,500 28,400 711 86,660

Standard reference material Percent recovery 11150 108.3% 98.9% 104.7% 98.9% 97.5% 97.2%

Standard reference material NIST 8704 found 11150 27,600 11,300 20,400 5,800 955 60,200

Standard reference material NIST 8704 true (National 

Institute of Standards and 

Technology, 2008)

11150 26,410 12,000 20,010 5,530 -- 61,000

Standard reference material Percent recovery 11150 104.5% 94.2% 101.9% 104.9% -- 98.7%

Standard reference material SCO-1 found 11150 19,800 15,500 23,100 6,800 869 71,800

Standard reference material SCO-1 true 

(Potts and others, 1992)

11150 18,700 16,400 23,000 6,670 899 72,370

Standard reference material Percent recovery 11150 105.9% 94.5% 100.4% 101.9% 96.7% 99.2%

Standard reference material NIST 2709 found 11150 20,900 15,900 21,500 12,400 644 79,500

Standard reference material NIST 2709 true (National 

Institute of Standards and 

Technology, 2003a)

11150 18,900 15,100 20,300 11,600 620 75,000

Standard reference material Percent recovery 11150 110.6% 105.3% 105.9% 106.9% 103.9% 106.0%

Standard reference material GSD-8 found 11150 2,290 2,040 36,300 4,590 180 61,900

Standard reference material GSD-8 true 

(Potts and others, 1992)

11150 1,790 1,510 23,500 3,490 130 40,800

Standard reference material Percent recovery 11150 127.9% 135.1% 154.5% 131.5% 138.5% 151.7%

Standard reference material NIST-2711 found 11150 27,100 10,100 24,300 11,600 807 65,200

Standard reference material NIST-2711 true (National 

Institute of Standards and 

Technology, 2003b)

11150 28,800 10,500 24,500 11,400 860 65,300

Standard reference material Percent recovery 11150 94.1% 96.2% 99.2% 101.8% 93.8% 99.8%

Standard reference material GSD-5 found 11150 39,500 5,510 18,200 2,580 596 81,900

Standard reference material GSD-5 true 

(Potts and others, 1992)

11150 38,200 5,900 17,400 2,970 610 81,300

Standard reference material Percent recovery 11150 103.4% 93.4% 104.6% 86.9% 97.7% 100.7%

Standard reference material GSD-3 found 11150 1,550 3,950 20,900 2,130 602 66,600

Standard reference material GSD-3 true 

(Potts and others, 1992)

11150 1,570 4,200 20,400 2,370 610 63,700

Standard reference material Percent recovery 11150 98.7% 94.0% 102.5% 89.9% 98.7% 104.6%

Appendix 4. Quality-assurance and quality-control data for major and trace elements in bed-sediment core samples collected in 

Lower Granite Reservoir and the Clearwater and Snake Rivers just above their confluence, 2010.

[Concentrations in micrograms per gram unless otherwise noted; #, number; <, less than lower reporting limit; %, percent; NIST, National Institute of Standards 

and Technology; --, not analyzed]
Appendix 4 71

Appendix 4. Quality-assurance and quality-control data for major and trace elements in bed-sediment core samples collected in 

Lower Granite Reservoir and the Clearwater and Snake Rivers just above their confluence, 2010.—Continued

[Concentrations in micrograms per gram unless otherwise noted; #, number; <, less than lower reporting limit; %, percent; NIST, National Institute of Standards 

and Technology; --, not analyzed]

Type of qualitycontrol sampleSample 

identifier

Set 

number Calcium Magnesium Potassium Sodium Phosphorus

Aluminum

Standard reference material MAG-1 found 11150 10,500 17,800 29,800 29,000 680 87,800

Standard reference material MAG-1 true 

(Potts and others, 1992)

11150 9,790 18,090 29,500 28,400 711 86,660

Standard reference material Percent recovery 11150 107.3% 98.4% 101.0% 102.1% 95.6% 101.3%

Standard reference material NIST 8704 found 11150 26,400 11,600 19,500 5,910 917 62,000

Standard reference material NIST 8704 true (National 

Institute of Standards and 

Technology, 2008)

11150 26,410 12,000 20,010 5,530 -- 61,000

Standard reference material Percent recovery 11150 100.0% 96.7% 97.5% 106.9% -- 101.6%

Environmental Core #84 65–75 11637 15,000 6,690 21,900 19,500 400 60,300

Laboratory replicate Core #84 65–75 replicate 11637 14,500 6,590 21,100 19,500 401 59,200

Blank Blank 11637 <100 13.4 <15 <25 <5 <50

Blank Blank 11637 <100 <6 <15 <25 7.6 <50

Blank Blank 11637 <100 <6 <15 112 21 <50

Blank Blank 11637 <100 <6 <15 <25 6 <50

Blank Blank 11637 <100 <6 <15 <25 <5 <50

Standard reference material MAG-1 found 11637 10,900 18,900 32,100 30,300 739 88,800

Standard reference material MAG-1 true 

(Potts and others, 1992)

11637 9,790 18,090 29,500 28,400 711 86,660

Standard reference material Percent recovery 11637 111.3% 104.5% 108.8% 106.7% 103.9% 102.5%

Standard reference material NIST 8704 found 11637 29,400 12,900 21,900 6,340 1,040 66,100

Standard reference material NIST 8704 true (National 

Institute of Standards and 

Technology, 2008)

11637 26,410 12,000 20,010 5,530 -- 61,000

Standard reference material Percent recovery 11637 111.3% 107.5% 109.4% 114.6% -- 108.4%

Standard reference material SCO-1 found 11637 19,500 16,500 23,700 6,900 912 74,300

Standard reference material SCO-1 true 

(Potts and others, 1992)

11637 18,700 16,400 23,000 6,670 899 72,370

Standard reference material Percent recovery 11637 104.3% 100.6% 103.0% 103.4% 101.4% 102.7%

Standard reference material NIST 2709 found 11637 21,200 16,100 21,900 12,400 670 80,700

Standard reference material NIST 2709 true (National 

Institute of Standards and 

Technology, 2003a)

11637 18,900 15,100 20,300 11,600 620 75,000

Standard reference material Percent recovery 11637 112.2% 106.6% 107.9% 106.9% 108.1% 107.6%

Standard reference material GSD-8 found 11637 1,510 1,390 24,000 3,130 127 40,300

Standard reference material GSD-8 true 

(Potts and others, 1992)

11637 1,790 1,510 23,500 3,490 130 40,800

Standard reference material Percent recovery 11637 84.4% 92.1% 102.1% 89.7% 97.7% 98.8%

Standard reference material NIST 2709 found 11637 19,000 14,500 19,700 11,300 595 71,500

Standard reference material NIST 2709 true (National 

Institute of Standards and 

Technology, 2003a)

11637 18,900 15,100 20,300 11,600 620 75,000

Standard reference material Percent recovery 11637 100.5% 96.0% 97.0% 97.4% 96.0% 95.3%
72 Grain-Size Distribution and Selected Major and Trace Element Concentrations in Bed-Sediment Cores

Appendix 4. Quality-assurance and quality-control data for major and trace elements in bed-sediment core samples collected in 

Lower Granite Reservoir and the Clearwater and Snake Rivers just above their confluence, 2010.—Continued

[Concentrations in micrograms per gram unless otherwise noted; #, number; <, less than lower reporting limit; %, percent; NIST, National Institute of Standards 

and Technology; --, not analyzed]

Type of qualitycontrol sampleSample 

identifier

Set 

number Barium Beryllium Bismuth Cadmium Cerium Cesium

Environmental Core #31 164–167 11150 723 1.5 5.90 0.27 58.1 3.2

Laboratory replicate Core #31 164–167 replicate 11150 712 1.6 6.42 0.28 58.9 3.3

Laboratory replicate Core #31 164–167 replicate 11150 715 1.5 5.97 0.27 58.9 3.2

Blank Blank 11150 <0.25 <0.03 <0.06 <0.007 <0.1 0.003

Blank Blank 11150 <0.25 <0.03 <0.06 <0.007 <0.1 0.008

Blank Blank 11150 0.73 <0.03 1.27 <0.007 0.26 0.007

Blank Blank 11150 <0.25 <0.03 <0.06 <0.007 <0.1 0.005

Blank Blank 11150 <0.25 <0.03 <0.06 <0.007 <0.1 <0.003

Blank Blank 11150 <0.25 0.03 <0.06 <0.007 <0.1 <0.003

Standard reference material MAG-1 found 11150 489 2.5 9.15 0.19 75.6 8.8

Standard reference material MAG-1 true 

(Potts and others, 1992)

11150 479 3.2 0.34 0.202 88 8.6

Standard reference material Percent recovery 11150 102.1% 78.1% 2,691.2% 94.1% 85.9% 102.3%

Standard reference material NIST 8704 found 11150 415 1.5 55.2 3.1 55.9 5.9

Standard reference material NIST 8704 true (National 

Institute of Standards and 

Technology, 2008)

11150 413 -- -- 2.94 66.5 5.83

Standard reference material Percent recovery 11150 100.5% -- -- 105.4% 84.1% 101.2%

Standard reference material SCO-1 found 11150 577 1.4 11.7 0.14 54.5 8.1

Standard reference material SCO-1 true 

(Potts and others, 1992)

11150 570 1.84 0.37 0.14 62 7.8

Standard reference material Percent recovery 11150 101.2% 76.1% 3,162.2% 100.0% 87.9% 103.8%

Standard reference material NIST 2709 found 11150 985 3.1 7.18 0.4 46.4 6

Standard reference material NIST 2709 true (National 

Institute of Standards and 

Technology, 2003a)

11150 968 -- -- 0.38 42 5.3

Standard reference material Percent recovery 11150 101.8% -- -- 105.3% 110.5% 113.2%

Standard reference material GSD-8 found 11150 653 2.1 11.5 <0.007 77.5 5

Standard reference material GSD-8 true 

(Potts and others, 1992)

11150 480 2 0.19 0.081 54 3.6

Standard reference material Percent recovery 11150 136.0% 105.0% 6,052.6% -- 143.5% 138.9%

Standard reference material NIST-2711 found 11150 726 1.9 415 40.5 73.2 7

Standard reference material NIST-2711 true (National 

Institute of Standards and 

Technology, 2003b)

11150 726 -- -- 41.7 69 6.1

Standard reference material Percent recovery 11150 100.0% -- -- 97.1% 106.1% 114.8%

Standard reference material GSD-5 found 11150 435 1.8 44 0.9 88.8 9.3

Standard reference material GSD-5 true 

(Potts and others, 1992)

11150 440 2.3 2.4 0.82 89 9.4

Standard reference material Percent recovery 11150 98.9% 78.3% 1,833.3% 109.8% 99.8% 98.9%

Standard reference material GSD-3 found 11150 616 1.1 15.9 0.2 61.8 7.9

Standard reference material GSD-3 true 

(Potts and others, 1992)

11150 615 1.5 0.79 0.1 64 7.8

Standard reference material Percent recovery 11150 100.2% 73.3% 2,012.7% 200.0% 96.6% 101.3%
Appendix 4 73

Appendix 4. Quality-assurance and quality-control data for major and trace elements in bed-sediment core samples collected in 

Lower Granite Reservoir and the Clearwater and Snake Rivers just above their confluence, 2010.—Continued

[Concentrations in micrograms per gram unless otherwise noted; #, number; <, less than lower reporting limit; %, percent; NIST, National Institute of Standards 

and Technology; --, not analyzed]

Type of qualitycontrol sampleSample 

identifier

Set 

number Barium Beryllium Bismuth Cadmium Cerium Cesium

Standard reference material MAG-1 found 11150 489 2.7 9.53 0.19 74.9 9

Standard reference material MAG-1 true 

(Potts and others, 1992)

11150 479 3.2 0.34 0.202 88 8.6

Standard reference material Percent recovery 11150 102.1% 84.4% 2,802.9% 94.1% 85.1% 104.7%

Standard reference material NIST 8704 found 11150 423 1.7 55.3 3 53.5 6.2

Standard reference material NIST 8704 true (National 

Institute of Standards and 

Technology, 2008)

11150 413 -- -- 2.94 66.5 5.83

Standard reference material Percent recovery 11150 102.4% -- -- 102.0% 80.5% 106.3%

Environmental Core #84 65–75 11637 1,040 1.8 10.4 0.02 34.7 2.5

Laboratory replicate Core #84 65–75 replicate 11637 1,010 1.9 10.4 0.02 35.6 2.4

Blank Blank 11637 <0.25 <0.03 <0.06 <0.007 <0.1 0.004

Blank Blank 11637 <0.25 <0.03 <0.06 <0.007 <0.1 0.004

Blank Blank 11637 0.27 <0.03 0.15 <0.007 <0.1 0.004

Blank Blank 11637 <0.25 <0.03 <0.06 <0.007 <0.1 <0.003

Blank Blank 11637 <0.25 <0.03 <0.06 <0.007 <0.1 <0.003

Standard reference material MAG-1 found 11637 544 2.9 10.7 0.31 91.7 9.6

Standard reference material MAG-1 true 

(Potts and others, 1992)

11637 479 3.20 0.34 0.20 88.0 8.60 

Standard reference material Percent recovery 11637 113.6% 90.6% 3,147.1% 153.5% 104.2% 111.6%

Standard reference material NIST 8704 found 11637 481 1.8 60.6 3.4 65.1 6.8

Standard reference material NIST 8704 true (National 

Institute of Standards and 

Technology, 2008)

11637 413 -- -- 2.94 66.5 5.83 

Standard reference material Percent recovery 11637 116.5% -- -- 115.6% 97.9% 116.6%

Standard reference material SCO-1 found 11637 628 1.6 12.4 0.15 60.1 8.7

Standard reference material SCO-1 true 

(Potts and others, 1992)

11637 570 1.84 0.37 0.14 62.0 7.80 

Standard reference material Percent recovery 11637 110.2% 87.0% 3,351.4% 107.1% 96.9% 111.5%

Standard reference material NIST 2709 found 11637 1,060 2.9 7.44 0.41 49.1 6.3

Standard reference material NIST 2709 true (National 

Institute of Standards and 

Technology, 2003a)

11637 968 -- -- 0.38 42.0 5.30 

Standard reference material Percent recovery 11637 109.5% -- -- 107.9% 116.9% 118.9%

Standard reference material GSD-8 found 11637 484 1.6 8.15 0.03 55.2 3.6

Standard reference material GSD-8 true 

(Potts and others, 1992)

11637 480 2.00 0.19 0.08 54.0 3.60 

Standard reference material Percent recovery 11637 100.8% 80.0% 4,289.5% 37.0% 102.2% 100.0%

Standard reference material NIST 2709 found 11637 905 2.9 6.58 0.34 42 5.4

Standard reference material NIST 2709 true (National 

Institute of Standards and 

Technology, 2003a)

11637 968 -- -- 0.38 42.0 5.30 

Standard reference material Percent recovery 11637 93.5% -- -- 89.5% 100.0% 101.9%
74 Grain-Size Distribution and Selected Major and Trace Element Concentrations in Bed-Sediment Cores

Appendix 4. Quality-assurance and quality-control data for major and trace elements in bed-sediment core samples collected in 

Lower Granite Reservoir and the Clearwater and Snake Rivers just above their confluence, 2010.—Continued

[Concentrations in micrograms per gram unless otherwise noted; #, number; <, less than lower reporting limit; %, percent; NIST, National Institute of Standards 

and Technology; --, not analyzed]

Type of qualitycontrol sampleSample 

identifier

Set 

number

Chromium Cobalt Copper Gallium Iron Lanthanum

Lead

Environmental Core #31 164–167 11150 52.4 20.9 36.7 19.8 45,000 30.0 15.5

Laboratory replicate Core #31 164–167 replicate 11150 52.4 20.8 39.3 19.6 44,800 30.4 16.8

Laboratory replicate Core #31 164–167 replicate 11150 52.9 20.7 36.6 19.8 45,300 30.1 15.8

Blank Blank 11150 <0.5 <0.03 <2 <0.015 <50 <0.05 <0.4

Blank Blank 11150 <0.5 <0.03 <2 <0.015 <50 <0.05 <0.4

Blank Blank 11150 <0.5 <0.03 <2 <0.015 <50 0.16 3.35

Blank Blank 11150 <0.5 <0.03 <2 <0.015 <50 <0.05 <0.4

Blank Blank 11150 <0.5 <0.03 <2 <0.015 <50 <0.05 <0.4

Blank Blank 11150 <0.5 <0.03 <2 <0.015 <50 <0.05 <0.4

Standard reference material MAG-1 found 11150 104 23.1 30.2 24.5 49,100 36.8 24.3

Standard reference material MAG-1 true 

(Potts and others, 1992)

11150 97 20.4 30 20.4 47,600 43 24

Standard reference material Percent recovery 11150 107.2% 113.2% 100.7% 120.1% 103.2% 85.6% 101.3%

Standard reference material NIST 8704 found 11150 121 14 91.4 16.7 40,200 26.6 146

Standard reference material NIST 8704 true (National 

Institute of Standards and 

Technology, 2008)

11150 121.9 13.6 -- -- 39,700 -- 150

Standard reference material Percent recovery 11150 99.3% 102.9% -- -- 101.3% -- 97.3%

Standard reference material SCO-1 found 11150 71.9 11.9 32.4 18.4 35,800 27.6 31.2

Standard reference material SCO-1 true 

(Potts and others, 1992)

11150 68 10.5 28.7 15 35,900 29.5 31

Standard reference material Percent recovery 11150 105.7% 113.3% 112.9% 122.7% 99.7% 93.6% 100.6%

Standard reference material NIST 2709 found 11150 122 14.4 37.8 18 36,900 23.5 18.7

Standard reference material NIST 2709 true (National 

Institute of Standards and 

Technology, 2003a)

11150 130 13.4 34.6 14 35,000 23 18.9

Standard reference material Percent recovery 11150 93.8% 107.5% 109.2% 128.6% 105.4% 102.2% 98.9%

Standard reference material GSD-8 found 11150 7.9 5 8.8 16.7 22,200 37.9 30.9

Standard reference material GSD-8 true 

(Potts and others, 1992)

11150 7.6 3.6 4.1 10.8 15,380 30 21

Standard reference material Percent recovery 11150 103.9% 138.9% 214.6% 154.6% 144.3% 126.3% 147.1%

Standard reference material NIST-2711 found 11150 43.1 10.1 112 17.2 28,400 38.4 1100

Standard reference material NIST-2711 true (National 

Institute of Standards and 

Technology, 2003b)

11150 47 10 114 15 28,900 40 1162

Standard reference material Percent recovery 11150 91.7% 101.0% 98.2% 114.7% 98.3% 96.0% 94.7%

Standard reference material GSD-5 found 11150 69.1 20.3 140 22.4 41,200 39.4 115

Standard reference material GSD-5 true 

(Potts and others, 1992)

11150 70 18.9 137 20.3 41,000 46 112

Standard reference material Percent recovery 11150 98.7% 107.4% 102.2% 110.3% 100.5% 85.7% 102.7%

Standard reference material GSD-3 found 11150 80.2 11.6 183 16.7 45,900 32.7 42

Standard reference material GSD-3 true 

(Potts and others, 1992)

11150 87 11.7 177 15.9 45,500 39 40

Standard reference material Percent recovery 11150 92.2% 99.1% 103.4% 105.0% 100.9% 83.8% 105.0%
Appendix 4 75

Appendix 4. Quality-assurance and quality-control data for major and trace elements in bed-sediment core samples collected in 

Lower Granite Reservoir and the Clearwater and Snake Rivers just above their confluence, 2010.—Continued

[Concentrations in micrograms per gram unless otherwise noted; #, number; <, less than lower reporting limit; %, percent; NIST, National Institute of Standards 

and Technology; --, not analyzed]

Type of qualitycontrol sampleSample 

identifier

Set 

number

Chromium Cobalt Copper Gallium Iron Lanthanum

Lead

Standard reference material MAG-1 found 11150 97.6 22 29.7 23.6 47,600 37.4 24.6

Standard reference material MAG-1 true 

(Potts and others, 1992)

11150 97 20.4 30 20.4 47,600 43 24

Standard reference material Percent recovery 11150 100.6% 107.8% 99.0% 115.7% 100.0% 87.0% 102.5%

Standard reference material NIST 8704 found 11150 115 13.6 89.7 16.2 38,600 25.7 145

Standard reference material NIST 8704 true (National 

Institute of Standards and 

Technology, 2008)

11150 121.9 13.6 -- -- 39,700 -- 150

Standard reference material Percent recovery 11150 94.3% 100.0% -- -- 97.2% -- 96.7%

Environmental Core #84 65–75 11637 22.9 11.1 18.9 16.3 22,300 18.8 28.6

Laboratory replicate Core #84 65–75 replicate 11637 21.3 10.9 19.7 16.1 21,700 19.4 28.7

Blank Blank 11637 <0.5 <0.03 <2 <0.015 <50 <0.05 <0.4

Blank Blank 11637 <0.5 <0.03 <2 <0.015 <50 <0.05 <0.4

Blank Blank 11637 <0.5 <0.03 <2 <0.015 <50 <0.05 0.41

Blank Blank 11637 <0.5 <0.03 <2 <0.015 <50 <0.05 <0.4

Blank Blank 11637 <0.5 <0.03 <2 0.02 <50 <0.05 <0.4

Standard reference material MAG-1 found 11637 107 23.8 32 25.9 51,300 44 28.3

Standard reference material MAG-1 true 

(Potts and others, 1992)

11637 97 20.4 30.0 20.4 47,600 43.0 24.0 

Standard reference material Percent recovery 11637 110.3% 116.7% 106.7% 127.0% 107.8% 102.3% 117.9%

Standard reference material NIST 8704 found 11637 127 15 98.1 18.1 43,600 31.1 162

Standard reference material NIST 8704 true (National 

Institute of Standards and 

Technology, 2008)

11637 122 13.6 -- -- 39,700 -- 150.0 

Standard reference material Percent recovery 11637 104.2% 110.3% -- -- 109.8% -- 108.0%

Standard reference material SCO-1 found 11637 72.2 12.1 30.2 19 37,100 30.3 33.1

Standard reference material SCO-1 true 

(Potts and others, 1992)

11637 68.0 10.5 28.7 15.0 35,900 29.5 31.0 

Standard reference material Percent recovery 11637 106.2% 115.2% 105.2% 126.7% 103.3% 102.7% 106.8%

Standard reference material NIST 2709 found 11637 120 14.8 38.8 19.2 38,300 24.3 19.9

Standard reference material NIST 2709 true (National 

Institute of Standards and 

Technology, 2003a)

11637 130 13.4 34.6 14.0 35,000 23.0 18.9 

Standard reference material Percent recovery 11637 92.3% 110.4% 112.1% 137.1% 109.4% 105.7% 105.3%

Standard reference material GSD-8 found 11637 9.7 3.4 5 11.1 15,000 26.7 22

Standard reference material GSD-8 true 

(Potts and others, 1992)

11637 7.60 3.6 4.1 10.8 15,380 30.0 21.0 

Standard reference material Percent recovery 11637 127.6% 94.4% 122.0% 102.8% 97.5% 89.0% 104.8%

Standard reference material NIST 2709 found 11637 104 12.7 33.4 16.1 33,800 21 17.5

Standard reference material NIST 2709 true (National 

Institute of Standards and 

Technology, 2003a)

11637 130 13.4 34.6 14.0 35,000 23.0 18.9 

Standard reference material Percent recovery 11637 80.0% 94.8% 96.5% 115.0% 96.6% 91.3% 92.6%
76 Grain-Size Distribution and Selected Major and Trace Element Concentrations in Bed-Sediment Cores

Appendix 4. Quality-assurance and quality-control data for major and trace elements in bed-sediment core samples collected in 

Lower Granite Reservoir and the Clearwater and Snake Rivers just above their confluence, 2010.—Continued

[Concentrations in micrograms per gram unless otherwise noted; #, number; <, less than lower reporting limit; %, percent; NIST, National Institute of Standards 

and Technology; --, not analyzed]

Type of qualitycontrol sampleSample 

identifier

Set 

number Lithium Manganese

Molybdenum

Nickel Niobium Rubidium

Environmental Core #31 164–167 11150 20.7 790 0.86 26.2 14 70.8

Laboratory replicate Core #31 164–167 replicate 11150 22.0 798 0.88 25.6 14 70.2

Laboratory replicate Core #31 164–167 replicate 11150 21.3 806 0.91 25.9 14 70.4

Blank Blank 11150 <0.3 <0.7 <0.05 <0.3 0.2 <0.014

Blank Blank 11150 0.3 <0.7 <0.05 <0.3 0.7 <0.014

Blank Blank 11150 <0.3 <0.7 <0.05 <0.3 0.48 <0.014

Blank Blank 11150 <0.3 <0.7 <0.05 <0.3 0.34 <0.014

Blank Blank 11150 <0.3 <0.7 <0.05 <0.3 0.1 <0.014

Blank Blank 11150 <0.3 <0.7 <0.05 <0.3 <0.1 <0.014

Standard reference material MAG-1 found 11150 74.3 780 1.1 51.9 14 158

Standard reference material MAG-1 true 

(Potts and others, 1992)

11150 79 760 1.6 53 12 149

Standard reference material Percent recovery 11150 94.1% 102.6% 68.8% 97.9% 116.7% 106.0%

Standard reference material NIST 8704 found 11150 44.3 585 4.6 43.2 7.6 107

Standard reference material NIST 8704 true (National 

Institute of Standards and 

Technology, 2008)

11150 -- 544 -- 42.9 -- --

Standard reference material Percent recovery 11150 -- 107.5% -- 100.7% -- --

Standard reference material SCO-1 found 11150 42 409 1.3 27.7 10 119

Standard reference material SCO-1 true 

(Potts and others, 1992)

11150 45 410 1.37 27 11 112

Standard reference material Percent recovery 11150 93.3% 99.8% 94.9% 102.6% 90.9% 106.3%

Standard reference material NIST 2709 found 11150 55.5 594 2.2 88 11 103

Standard reference material NIST 2709 true (National 

Institute of Standards and 

Technology, 2003a)

11150 -- 538 2 88 -- 96

Standard reference material Percent recovery 11150 -- 110.4% 110.0% 100.0% -- 107.3%

Standard reference material GSD-8 found 11150 17.6 510 0.82 2.4 51 198

Standard reference material GSD-8 true 

(Potts and others, 1992)

11150 13.2 310 0.54 2.7 35 132

Standard reference material Percent recovery 11150 133.3% 164.5% 151.9% 88.9% 145.7% 150.0%

Standard reference material NIST-2711 found 11150 26.5 655 1.7 20 16 120

Standard reference material NIST-2711 true (National 

Institute of Standards and 

Technology, 2003b)

11150 -- 638 1.6 20.6 -- 110

Standard reference material Percent recovery 11150 -- 102.7% 106.3% 97.1% -- 109.1%

Standard reference material GSD-5 found 11150 43.3 1,220 1.3 37.6 11 128

Standard reference material GSD-5 true 

(Potts and others, 1992)

11150 45 1,160 1.2 34 19 118

Standard reference material Percent recovery 11150 96.2% 105.2% 108.3% 110.6% 57.9% 108.5%

Standard reference material GSD-3 found 11150 32.4 424 96.9 27.2 6.8 83.2

Standard reference material GSD-3 true 

(Potts and others, 1992)

11150 33 390 92 25.6 16 79

Standard reference material Percent recovery 11150 98.2% 108.7% 105.3% 106.3% 42.5% 105.3%
Appendix 4 77

Appendix 4. Quality-assurance and quality-control data for major and trace elements in bed-sediment core samples collected in 

Lower Granite Reservoir and the Clearwater and Snake Rivers just above their confluence, 2010.—Continued

[Concentrations in micrograms per gram unless otherwise noted; #, number; <, less than lower reporting limit; %, percent; NIST, National Institute of Standards 

and Technology; --, not analyzed]

Type of qualitycontrol sampleSample 

identifier

Set 

number Lithium Manganese

Molybdenum

Nickel Niobium Rubidium

Standard reference material MAG-1 found 11150 74.8 743 1.1 50.5 12 149

Standard reference material MAG-1 true 

(Potts and others, 1992)

11150 79 760 1.6 53 12 149

Standard reference material Percent recovery 11150 94.7% 97.8% 68.8% 95.3% 100.0% 100.0%

Standard reference material NIST 8704 found 11150 44.3 559 4.5 42.6 7 102

Standard reference material NIST 8704 true (National 

Institute of Standards and 

Technology, 2008)

11150 -- 544 -- 42.9 -- --

Standard reference material Percent recovery 11150 -- 102.8% -- 99.3% -- --

Environmental Core #84 65–75 11637 0.02 389 0.47 12.7 12 92.3

Laboratory replicate Core #84 65–75 replicate 11637 -- 375 0.47 12 12 91.7

Blank Blank 11637 <0.3 2.3 <0.05 <0.3 <0.1 <0.014

Blank Blank 11637 <0.3 <0.7 <0.05 <0.3 2 <0.014

Blank Blank 11637 <0.3 <0.7 <0.05 <0.3 0.58 <0.014

Blank Blank 11637 <0.3 <0.7 <0.05 <0.3 0.31 <0.014

Blank Blank 11637 0.8 <0.7 <0.05 <0.3 0.2 <0.014

Standard reference material MAG-1 found 11637 79.2 809 1.2 54.5 15 161

Standard reference material MAG-1 true 

(Potts and others, 1992)

11637 79.0 760 1.60 53.0 12.0 149 

Standard reference material Percent recovery 11637 100.3% 106.4% 75.0% 102.8% 125.0% 108.1%

Standard reference material NIST 8704 found 11637 48 625 4.1 47.8 9.7 114

Standard reference material NIST 8704 true (National 

Institute of Standards and 

Technology, 2008)

11637 -- 544 -- 42.9 -- --

Standard reference material Percent recovery 11637 -- 114.9% -- 111.4% -- --

Standard reference material SCO-1 found 11637 44.9 413 1.2 27.9 10 120

Standard reference material SCO-1 true 

(Potts and others, 1992)

11637 45.0 410 1.37 27.0 11.0 112 

Standard reference material Percent recovery 11637 99.8% 100.7% 87.6% 103.3% 90.9% 107.1%

Standard reference material NIST 2709 found 11637 56.3 610 2.2 90 9.4 105

Standard reference material NIST 2709 true (National 

Institute of Standards and 

Technology, 2003a)

11637 -- 538 2 88.0 -- 96 

Standard reference material Percent recovery 11637 -- 113.4% 110.0% 102.3% -- 109.4%

Standard reference material GSD-8 found 11637 11.8 336 0.56 1.6 33 135

Standard reference material GSD-8 true 

(Potts and others, 1992)

11637 13.2 310 0.54 2.7 35.0 132 

Standard reference material Percent recovery 11637 89.4% 108.4% 103.7% 59.3% 94.3% 102.3%

Standard reference material NIST 2709 found 11637 52 540 1.9 77.8 8.9 90.7

Standard reference material NIST 2709 true (National 

Institute of Standards and 

Technology, 2003a)

11637 -- 538 2 88.0 -- 96 

Standard reference material Percent recovery 11637 -- 100.4% 95.0% 88.4% -- 94.5%
78 Grain-Size Distribution and Selected Major and Trace Element Concentrations in Bed-Sediment Cores

Appendix 4. Quality-assurance and quality-control data for major and trace elements in bed-sediment core samples collected in 

Lower Granite Reservoir and the Clearwater and Snake Rivers just above their confluence, 2010.—Continued

[Concentrations in micrograms per gram unless otherwise noted; #, number; <, less than lower reporting limit; %, percent; NIST, National Institute of Standards 

and Technology; --, not analyzed]

Type of qualitycontrol sampleSample 

identifier

Set 

number Scandium Silver Strontium Thallium Titanium Vanadium

Environmental Core #31 164–167 11150 17.5 <0.01 349 0.40 6,170 160

Laboratory replicate Core #31 164–167 replicate 11150 17.3 <0.01 343 0.40 6,090 158

Laboratory replicate Core #31 164–167 replicate 11150 17.5 <0.01 347 0.41 6,180 161

Blank Blank 11150 <0.04 12.3 <0.8 <0.08 <40 <0.15

Blank Blank 11150 <0.04 <0.01 <0.8 <0.08 <40 <0.15

Blank Blank 11150 <0.04 <0.01 <0.8 <0.08 <40 <0.15

Blank Blank 11150 <0.04 <0.01 <0.8 <0.08 <40 <0.15

Blank Blank 11150 <0.04 2.17 <0.8 <0.08 <40 <0.15

Blank Blank 11150 <0.04 0.816 <0.8 <0.08 <40 <0.15

Standard reference material MAG-1 found 11150 18 <0.01 148 0.71 3,400 153

Standard reference material MAG-1 true 

(Potts and others, 1992)

11150 17.2 0.08 146 0.59 4,500 140

Standard reference material Percent recovery 11150 104.7% -- 101.4% 120.3% 75.6% 109.3%

Standard reference material NIST 8704 found 11150 11.4 <0.01 137 1.06 2,200 97.8

Standard reference material NIST 8704 true (National 

Institute of Standards and 

Technology, 2008)

11150 11.26 -- -- -- 4,570 94.6

Standard reference material Percent recovery 11150 101.2% -- -- -- 48.1% 103.4%

Standard reference material SCO-1 found 11150 11.9 <0.01 175 0.69 2,880 145

Standard reference material SCO-1 true 

(Potts and others, 1992)

11150 10.8 0.134 174 0.72 3,760 131

Standard reference material Percent recovery 11150 110.2% -- 100.6% 95.8% 76.6% 110.7%

Standard reference material NIST 2709 found 11150 12.8 <0.01 248 0.68 3,250 127

Standard reference material NIST 2709 true (National 

Institute of Standards and 

Technology, 2003a)

11150 12 -- 231 0.74 3,420 112

Standard reference material Percent recovery 11150 106.7% -- 107.4% 91.9% 95.0% 113.4%

Standard reference material GSD-8 found 11150 7.5 <0.01 74.9 1.08 4,270 36

Standard reference material GSD-8 true 

(Potts and others, 1992)

11150 5.7 0.062 52 0.78 3,660 26

Standard reference material Percent recovery 11150 131.6% -- 144.0% 138.5% 116.7% 138.5%

Standard reference material NIST-2711 found 11150 9.3 2.64 253 2.55 2,300 85.8

Standard reference material NIST-2711 true (National 

Institute of Standards and 

Technology, 2003b)

11150 9 4.63 245.3 2.47 3,060 81.6

Standard reference material Percent recovery 11150 103.3% 57.0% 103.1% 103.2% 75.2% 105.1%

Standard reference material GSD-5 found 11150 13.9 <0.01 219 1.19 3,370 114

Standard reference material GSD-5 true 

(Potts and others, 1992)

11150 14.5 0.36 204 1.16 5,400 109

Standard reference material Percent recovery 11150 95.9% -- 107.4% 102.6% 62.4% 104.6%

Standard reference material GSD-3 found 11150 12.9 <0.01 93.7 0.48 3,200 124

Standard reference material GSD-3 true 

(Potts and others, 1992)

11150 14.3 0.59 90 0.58 6,360 120

Standard reference material Percent recovery 11150 90.2% -- 104.1% 82.8% 50.3% 103.3%
Appendix 4 79

Appendix 4. Quality-assurance and quality-control data for major and trace elements in bed-sediment core samples collected in 

Lower Granite Reservoir and the Clearwater and Snake Rivers just above their confluence, 2010.—Continued

[Concentrations in micrograms per gram unless otherwise noted; #, number; <, less than lower reporting limit; %, percent; NIST, National Institute of Standards 

and Technology; --, not analyzed]

Type of qualitycontrol sampleSample 

identifier

Set 

number Scandium Silver Strontium Thallium Titanium Vanadium

Standard reference material MAG-1 found 11150 17.5 <0.01 141 0.73 3,150 145

Standard reference material MAG-1 true 

(Potts and others, 1992)

11150 17.2 0.08 146 0.59 4,500 140

Standard reference material Percent recovery 11150 101.7% -- 96.6% 123.7% 70.0% 103.6%

Standard reference material NIST 8704 found 11150 11.6 <0.01 133 1.06 2,080 94.9

Standard reference material NIST 8704 true (National 

Institute of Standards and 

Technology, 2008)

11150 11.26 -- -- -- 4,570 94.6

Standard reference material Percent recovery 11150 103.0% -- -- -- 45.5% 100.3%

Environmental Core #84 65–75 11637 7.6 0.029 324 0.47 2,640 71.4

Laboratory replicate Core #84 65–75 replicate 11637 7.4 0.039 323 0.47 2,580 69.9

Blank Blank 11637 <0.04 0.029 <0.8 <0.08 <40 <0.15

Blank Blank 11637 <0.04 <0.01 <0.8 <0.08 <40 <0.15

Blank Blank 11637 <0.04 <0.01 <0.8 <0.08 <40 <0.15

Blank Blank 11637 <0.04 <0.01 <0.8 <0.08 <40 <0.15

Blank Blank 11637 <0.04 <0.01 <0.8 <0.08 <40 <0.15

Standard reference material MAG-1 found 11637 18.6 0.065 155 0.75 3,640 155

Standard reference material MAG-1 true 

(Potts and others, 1992)

11637 17.2 0.08 146 0.59 4,500 140 

Standard reference material Percent recovery 11637 108.1% 81.3% 106.2% 127.1% 80.9% 110.7%

Standard reference material NIST 8704 found 11637 12.8 0.317 152 1.14 2,670 103

Standard reference material NIST 8704 true (National 

Institute of Standards and 

Technology, 2008)

11637 11.3 -- -- -- 4,570 94.6 

Standard reference material Percent recovery 11637 113.7% -- -- -- 58.4% 108.9%

Standard reference material SCO-1 found 11637 12.5 0.103 181 0.72 2,850 143

Standard reference material SCO-1 true 

(Potts and others, 1992)

11637 10.8 0.134 174 0.72 3,760 131

Standard reference material Percent recovery 11637 115.7% 76.9% 104.0% 100.0% 75.8% 109.2%

Standard reference material NIST 2709 found 11637 13.3 0.339 255 0.66 3,190 126

Standard reference material NIST 2709 true (National 

Institute of Standards and 

Technology, 2003a)

11637 12.0 -- 231 0.74 3,420 112.0 

Standard reference material Percent recovery 11637 110.8% -- 110.4% 89.2% 93.3% 112.5%

Standard reference material GSD-8 found 11637 5 <0.01 51.4 0.72 2,750 24.6

Standard reference material GSD-8 true 

(Potts and others, 1992)

11637 5.7 0.062 52.0 0.78 3,660 26

Standard reference material Percent recovery 11637 87.7% -- 98.8% 92.3% 75.1% 94.6%

Standard reference material NIST 2709 found 11637 11.3 0.306 218 0.65 2,840 109

Standard reference material NIST 2709 true (National 

Institute of Standards and 

Technology, 2003a)

11637 12.0 -- 231 0.74 3,420 112.0 

Standard reference material Percent recovery 11637 94.2% -- 94.4% 87.8% 83.0% 97.3%
80 Grain-Size Distribution and Selected Major and Trace Element Concentrations in Bed-Sediment Cores

Appendix 4. Quality-assurance and quality-control data for major and trace elements in bed-sediment core samples collected in 

Lower Granite Reservoir and the Clearwater and Snake Rivers just above their confluence, 2010.—Continued

[Concentrations in micrograms per gram unless otherwise noted; #, number; <, less than lower reporting limit; %, percent; NIST, National Institute of Standards 

and Technology; --, not analyzed]

Type of qualitycontrol sampleSample 

identifier

Set 

number Yttrium Zinc Antimony Arsenic Thorium Uranium

Environmental Core #31 164–167 11150 25.2 102 0.81 6.1 7.62 3.73

Laboratory replicate Core #31 164–167 replicate 11150 24.7 102 2.0 6.2 8.36 3.81

Laboratory replicate Core #31 164–167 replicate 11150 25.0 103 0.77 6.0 7.82 3.85

Blank Blank 11150 <0.05 <3 0.32 <1 <0.1 <0.02

Blank Blank 11150 <0.05 <3 <0.04 <1 <0.1 <0.02

Blank Blank 11150 <0.05 <3 <0.04 <1 <0.1 <0.02

Blank Blank 11150 <0.05 <3 <0.04 <1 <0.1 <0.02

Blank Blank 11150 <0.05 <3 0.23 <1 <0.1 <0.02

Blank Blank 11150 <0.05 <3 0.22 <1 <0.1 <0.02

Standard reference material MAG-1 found 11150 19.8 136 1 9.8 11 2.47

Standard reference material MAG-1 true 

(Potts and others, 1992)

11150 28 130 0.96 9.2 11.9 2.7

Standard reference material Percent recovery 11150 70.7% 104.6% 104.2% 106.5% 92.4% 91.5%

Standard reference material NIST 8704 found 11150 20 393 2.9 17 8.44 2.72

Standard reference material NIST 8704 true (National 

Institute of Standards and 

Technology, 2008)

11150 -- 408 3.07 -- 9.07 3.09

Standard reference material Percent recovery 11150 -- 96.3% 94.5% -- 93.1% 88.0%

Standard reference material SCO-1 found 11150 17.8 107 2.6 12.7 8.92 2.7

Standard reference material SCO-1 true 

(Potts and others, 1992)

11150 26 103 2.5 12.4 9.7 3

Standard reference material Percent recovery 11150 68.5% 103.9% 104.0% 102.4% 92.0% 90.0%

Standard reference material NIST 2709 found 11150 16.2 111 7.4 19.2 11.1 3.06

Standard reference material NIST 2709 true (National 

Institute of Standards and 

Technology, 2003a)

11150 18 106 7.9 17.7 11 3

Standard reference material Percent recovery 11150 90.0% 104.7% 93.7% 108.5% 100.9% 102.0%

Standard reference material GSD-8 found 11150 19.2 65.9 0.39 4 19.5 4.37

Standard reference material GSD-8 true 

(Potts and others, 1992)

11150 18 43 0.24 2.4 13.4 3

Standard reference material Percent recovery 11150 106.7% 153.3% 162.5% 166.7% 145.5% 145.7%

Standard reference material NIST-2711 found 11150 24.7 340 19.6 103 13.5 2.49

Standard reference material NIST-2711 true (National 

Institute of Standards and 

Technology, 2003b)

11150 25 350.4 19.4 105 14 2.6

Standard reference material Percent recovery 11150 98.8% 97.0% 101.0% 98.1% 96.4% 95.8%

Standard reference material GSD-5 found 11150 16.9 257 4.2 78.1 14.7 2.37

Standard reference material GSD-5 true 

(Potts and others, 1992)

11150 26 243 3.9 75 15.2 2.6

Standard reference material Percent recovery 11150 65.0% 105.8% 107.7% 104.1% 96.7% 91.2%

Standard reference material GSD-3 found 11150 12 52.6 6.5 18.6 8.54 1.43

Standard reference material GSD-3 true 

(Potts and others, 1992)

11150 22 52 5.4 17.6 9.2 1.86

Standard reference material Percent recovery 11150 54.5% 101.2% 120.4% 105.7% 92.8% 76.9%
Appendix 4 81

Appendix 4. Quality-assurance and quality-control data for major and trace elements in bed-sediment core samples collected in 

Lower Granite Reservoir and the Clearwater and Snake Rivers just above their confluence, 2010.—Continued

[Concentrations in micrograms per gram unless otherwise noted; #, number; <, less than lower reporting limit; %, percent; NIST, National Institute of Standards 

and Technology; --, not analyzed]

Type of qualitycontrol sampleSample 

identifier

Set 

number Yttrium Zinc Antimony Arsenic Thorium Uranium

Standard reference material MAG-1 found 11150 19.2 132 1 9.2 11.5 2.63

Standard reference material MAG-1 true 

(Potts and others, 1992)

11150 28 130 0.96 9.2 11.9 2.7

Standard reference material Percent recovery 11150 68.6% 101.5% 104.2% 100.0% 96.6% 97.4%

Standard reference material NIST 8704 found 11150 19.6 385 2.9 16.5 8.3 2.81

Standard reference material NIST 8704 true (National 

Institute of Standards and 

Technology, 2008)

11150 -- 408 3.07 -- 9.07 3.09

Standard reference material Percent recovery 11150 -- 94.4% 94.5% -- 91.5% 90.9%

Environmental Core #84 65–75 11637 13.1 54.0 0.38 3.1 5.88 1.59

Laboratory replicate Core #84 65–75 replicate 11637 12.2 53.4 0.27 3.0 5.93 1.44

Blank Blank 11637 <0.05 <3 0.2 <1 <0.1 <0.02

Blank Blank 11637 <0.05 <3 0.05 <1 <0.1 <0.02

Blank Blank 11637 <0.05 <3 <0.04 <1 <0.1 <0.02

Blank Blank 11637 <0.05 <3 <0.04 <1 <0.1 <0.02

Blank Blank 11637 <0.05 <3 0.34 <1 <0.1 <0.02

Standard reference material MAG-1 found 11637 22.2 142 0.91 9.9 12.9 2.92

Standard reference material MAG-1 true 

(Potts and others, 1992)

11637 28.0 130 0.96 9.2 11.9 2.70 

Standard reference material Percent recovery 11637 79.3% 109.2% 94.8% 107.6% 108.4% 108.1%

Standard reference material NIST 8704 found 11637 22.8 431 3.4 18.2 9.57 3.14

Standard reference material NIST 8704 true (National 

Institute of Standards and 

Technology, 2008)

11637 -- 408 3.07 -- 9.1 3.09 

Standard reference material Percent recovery 11637 -- 105.6% 110.7% -- 105.5% 101.6%

Standard reference material SCO-1 found 11637 18.7 108 2.6 12.8 10.1 3.02

Standard reference material SCO-1 true 

(Potts and others, 1992)

11637 26.0 103 2.50 12.4 9.7 3.00 

Standard reference material Percent recovery 11637 71.9% 104.9% 104.0% 103.2% 104.1% 100.7%

Standard reference material NIST 2709 found 11637 16.6 114 7.1 19.4 12.1 3.12

Standard reference material NIST 2709 true (National 

Institute of Standards and 

Technology, 2003a)

11637 18.0 106 7.90 17.7 11.0 3.00 

Standard reference material Percent recovery 11637 92.2% 107.5% 89.9% 109.6% 110.0% 104.0%

Standard reference material GSD-8 found 11637 13.3 47 0.05 2.7 13.5 3.05

Standard reference material GSD-8 true 

(Potts and others, 1992)

11637 18.0 43.0 0.24 2.4 13.4 3.00 

Standard reference material Percent recovery 11637 73.9% 109.3% 20.8% 112.5% 100.7% 101.7%

Standard reference material NIST 2709 found 11637 14.3 99.3 6.7 16.8 10.4 2.78

Standard reference material NIST 2709 true (National 

Institute of Standards and 

Technology, 2003a)

11637 18.0 106 7.90 17.7 11.0 3.00 

Standard reference material Percent recovery 11637 79.4% 93.7% 84.8% 94.9% 94.5% 92.7%
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Braun and others—Grain-Size Distribution and Selected Major and Trace Element Concentrations in Bed-Sediment Cores—SIR 2012–5219

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