U.S. Department of the Interior

U.S. Geological Survey

Prepared in cooperation with 

U.S. Forest Service and Bureau of Land Management

Quantification of Metal Loads and Assessment of 

Metal Sources in Upper Beaver Creek Watershed, 

Shoshone County, Idaho, May and June 2002

Water-Resources Investigations Report 03–4206
U.S. Department of the Interior

U.S. Geological Survey

Quantification of Metal Loads and Assessment of 

Metal Sources in Upper Beaver Creek Watershed, 

Shoshone County, Idaho, May and June 2002

By Douglas S. Ott and David W. Clark

Water-Resources Investigations Report 03–4206

Prepared in cooperation with 

U.S. Forest Service and Bureau of Land Management

Boise, Idaho

2003
U.S. DEPARTMENT OF THE INTERIOR

Gale A. Norton, Secretary

U.S. GEOLOGICAL SURVEY

Charles G. Groat, Director

Any use of firm, trade, and brand names in this report is for identification purposes

only and does not constitute endorsement by the U.S. Government.

Additional information can be obtained from:

District Chief

U.S. Geological Survey

230 Collins Road

Boise, ID 83702-4520

http://idaho.usgs.gov

Copies of this report also are available in PDF format, 

which can be viewed using Adobe Acrobat Reader, at 

URL:

http://idaho.usgs.gov/public/reports.html 
Contents iii

CONTENTS

Contents

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

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

Purpose and scope. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4

Description of study area . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4

Acknowledgments . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5

Data collection methods . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5

Site selection. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5

Streamflow . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5

Subsurface flow. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5

Synoptic water-quality sampling . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5

Quality assurance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7

Streamflow. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8

Synoptic sampling event S1 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8

Synoptic sampling event S2 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8

Synoptic sampling event S3 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11

Water quality . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11

Quantification of metal loads . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15

Cadmium. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18

Lead . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19

Zinc . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19

Assessment of metal sources. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20

Cadmium. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20

Lead . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21

Zinc . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21

Summary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22

References cited . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23

FIGURES

1. Map showing location of Coeur d’Alene River Basin, Coeur d’Alene National Forest, and study 

area in upper Beaver Creek watershed, Shoshone County, Idaho . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2

2. Map showing location of synoptic sampling sites and selected mining structures in upper Beaver 

Creek watershed, Shoshone County, Idaho . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3

3–10. Graphs showing:

3. Instantaneous streamflow at sampling sites in upper Beaver Creek and Carbon Creek 

watersheds, Shoshone County, Idaho, May and June 2002 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7

4. Unaccounted gain or loss of streamflow and dissolved cadmium, lead, and zinc loads for each 

subreach in upper Beaver Creek, Shoshone County, Idaho, May and June 2002 . . . . . . . . . . . . . . . 9

5. Unaccounted gain or loss of streamflow and dissolved cadmium, lead, and zinc loads for each 

subreach in Carbon Creek, Shoshone County, Idaho, May and June 2002 . . . . . . . . . . . . . . . . . . . . 10

6. Dissolved concentrations of cadmium, lead, and zinc in upper Beaver Creek, Shoshone 

County, Idaho, May and June 2002 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12

7. Dissolved concentrations of cadmium, lead, and zinc in Carbon Creek, Shoshone County, 

Idaho, May and June 2002 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13
iv Quantification of Metal Loads and Assessment of Metal Sources in Upper Beaver Creek Watershed, Shoshone County, Idaho, May and June 2002

8. Dissolved concentrations of cadmium, lead, and zinc in subsurface water in upper Beaver 

Creek watershed, Shoshone County, Idaho, May and June 2002. . . . . . . . . . . . . . . . . . . . . . . . . . . . 14

9. Dissolved cadmium, lead, and zinc loads in upper Beaver Creek, Shoshone County, Idaho, 

May and June 2002 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16

10. Dissolved cadmium, lead, and zinc loads in Carbon Creek, Shoshone County, Idaho, May 

and June 2002 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17

TABLES

1. Selected water-quality data for synoptic samples and field blank samples collected in upper 

Beaver Creek watershed, Shoshone County, Idaho, May and June 2002 . . . . . . . . . . . . . . . . . . . . . . . . . 27

2. Minimum reporting level of major ion, nutrient, and trace-element concentrations analyzed in 

water-quality samples from upper Beaver Creek watershed, Shoshone County, Idaho, May and 

June 2002 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6

3. Instantaneous loads of selected metals in upper Beaver Creek watershed, Shoshone County, 

Idaho, May and June 2002. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15

CONVERSION FACTORS, OTHER ABBREVIATED UNITS, AND VERTICAL DATUM

Multiply By To obtain

cubic foot per second (ft3/s) 0.02832 cubic meter per second (m3/s)

foot (ft) 0.3048 meter (m)

inch (in.) 2.540 centimeter (cm)

mile (mi) 1.609 kilometer (km)

Temperature is given in degrees Celsius (°C), which may be converted to degrees Fahrenheit (°F) by using the 

following equation:

°F=(1.8) (°C)+32

Other abbreviated units:

L liter

μg/L microgram per liter

μm micrometer

μg/s microgram per second

mg/L milligram per liter

Sea level: In this report, “sea level” refers to the National Geodetic Vertical Datum of 1929—a geodetic datum 

derived from a general adjustment of the first-order level nets of the United States and Canada, formerly called Sea 

Level Datum of 1929.
Introduction 1

Quantification of Metal Loads and Assessment of 

Metal Sources in Upper Beaver Creek Watershed, 

Shoshone County, Idaho, May and June 2002

By Douglas S. Ott and David W. Clark

Abstract

Abandoned mine lands contribute to significant 

water-quality degradation in the Beaver Creek watershed in northern Idaho. Streams in this watershed drain 

the northern flank of the Coeur d’Alene mining district, 

one of the world’s largest producers of silver and one 

of the country’s major historical producers of lead and 

zinc for more than 100 years. Effective cleanup of 

these streams will depend on accurate characterization 

of metal concentrations in streams and various sources 

of these metals.

Cadmium, lead, and zinc loads entering Beaver 

Creek and its major tributary, Carbon Creek, were 

quantified, and source areas for these metals were 

assessed during May and June 2002. Metal loads were 

calculated for main-stem and surface-inflow sites by 

combining measured streamflow with dissolved cadmium, lead, and zinc concentrations analyzed in waterquality samples collected during three synoptic sampling events. To assess the effects of surface and shallow subsurface inflows on the gain or loss of streamflow and metal loads, Beaver and Carbon Creeks were 

divided into subreaches. Four subreaches were defined 

on Beaver Creek using five main-stem sampling sites 

(UBC3, UBC5, UBC8, BC10, and BC14); two subreaches were defined on Carbon Creek using three 

main-stem sampling sites (CC2, CC6, and CC9).

During each of the synoptic sampling events, concentrations of cadmium and zinc were highest in samples collected at the Carlisle Mine adit between sites 

CC2 and CC6. During two of the three synoptic sampling events, the concentration of lead was highest in 

samples collected from a left-bank seep downgradient 

from the Idora Mill between sites UBC3 and UBC5.

The largest identified cadmium and zinc source to 

Beaver Creek is the surface inflow from Carbon Creek 

(between sites UBC8 and BC10), which accounted for 

45 to 72 percent of the main-stem cadmium load and 

49 to 89 percent of the main-stem zinc load in Beaver 

Creek. Another large source of cadmium and zinc to 

Beaver Creek is subsurface flow through the tiered 

flotation tailings pile near Carbon Center (between 

sites BC10 and BC14) into Beaver Creek. 

Amounts of lead contributed by source areas to 

Beaver Creek vary with streamflow conditions. During 

high streamflow, the largest source of lead to Beaver 

Creek is the remobilization of fine-grained (less than 

0.45-micrometer), lead-enriched particulates from the 

streambed throughout the study area. During low 

streamflow, bank seepage of subsurface water into 

Beaver Creek in the subreach downgradient from the 

Idora Mill (between sites UBC3 and UBC5) is the 

major source of lead to Beaver Creek. During each 

synoptic sampling event, Carbon Creek is a major 

source of lead to Beaver Creek.

The Carlisle Mine adit (between CC2 and CC6) 

is the largest source of cadmium and zinc to Carbon 

Creek and, ultimately, to Beaver Creek, and accounted 

for 57 to 88 percent of the total main-stem cadmium 

load and 56 to 88 percent of the total main-stem zinc 

load in Carbon Creek during each of the synoptic sampling events. Another source of cadmium and zinc to 

Carbon Creek is resurfacing cadmium- and zincenriched hyporheic flow (possibly originating from 

the Carlisle adit or the Carlisle Mill) between sites 

CC6 and CC9. 

As in Beaver Creek, amounts of lead contributed 

to Carbon Creek by source areas vary with streamflow 

conditions. During high streamflows, increased discharge from the Carlisle Mine adit appears to be the 

largest source of lead to Carbon Creek; during low 

streamflows, resurfacing lead-enriched hyporheic flow 

appears to be the major source of lead to Carbon Creek.

INTRODUCTION

Introduction

The upper Beaver Creek watershed (figs. 1 and 2), 

located in the Coeur d’Alene River Basin in north 

Idaho, drains the northern flank of the famed Coeur 
2 Quantification of Metal Loads and Assessment of Metal Sources in Upper Beaver Creek Watershed, Shoshone County, Idaho, May and June 2002

0 5 1 10 5 20 MILES

0 5 1 10 5 20 KILOMETERS

Base from U.S. Geological Survey digital data, State 1:2,000,000, 1995;

Hydrologic Unit Map 1:250,000, 1994; National Forest from Interior

Columbia Basin Ecosystem Management Project (ICBEMP) 1:100,000;

Transverse Mercator projection, Factor at central meridian: 0.9996

Longitude of central meridian: -114° 00'; Latitude of origin: 42° 00'

False easting (meters): 500,000; False northing (meters): 100,000

River

North

Fork

Coeur d'Alene

River

St Joe River

Fork

Spokane

South

Coeur

d'Alene

Lake

BONNER

BENEWAH

SHOSHONE

KOOTENAI

117° 00' 116° 45' 116° 30' 116° 15'

116° 00'

115° 45'

48° 00'

47° 45'

47° 30'

EXPLANATION

Upper Beaver Creek watershed

Coeur d'Alene National Forest

Coeur d'Alene River Basin

Study

area

IDAHO

Figure 1. Location of Coeur d'Alene River Basin, Coeur d'Alene National Forest, and study area in upper Beaver Creek watershed,

Shoshone County, Idaho.
0 

0 0

Base from U.S. Geological Survey digital dataHydrologic Unit Map 1:250,000, 1994; Streams Transverse Mercator projection, Factor at ceLongitude of central meridian: -114° 00'; Latit

False easting (meters): 500,000; False northing 

Beaver

Pioneer

Gulch

Creek

Ferguson Dobson

Gulch

Gulch

Missoula

Carbon Creek

Creek

Carlisle Mill

Carbon Center

(tailing piles)

Idora Mill

Ferguson

UBC3 UBC4

UBC5 PUBC4

UBC-A1

CC4 CC2

CC6

CC9

PCC8 UBC8 BC10 PC1

PBC10

PBC10A

BC14

BC12

PBC12

PBC11

DC1

115° 55'

115° 54'

115° 53'

115° 52'

115° 51'

47° 33'

47° 34'

47° 35'

47° 33'

4

115° 55' 115° 54'

115° 53'

115° 52'

115° 51'

EXPLANATION

Piezometer and identification numberBeaver Creek main-stem sampling site and identification numberCarbon Creek main-stem sampling site and identification numberCumulative surface-inflow sampling site and identification number

PUBC4

CC9

DC1

UBC8

Figure 2. Location of synoptic sampling sites and selected mining structures in upper Beaver Creek watershed, Shoshone County, Idaho.

Introduction 3
4 Quantification of Metal Loads and Assessment of Metal Sources in Upper Beaver Creek Watershed, Shoshone County, Idaho, May and June 2002

d’Alene mining district. From the late 1800s to the 

early 1980s, the district was one of the world’s largest 

producers of silver and one of the Nation’s major producers of lead and zinc. Mining activities over more 

than 100 years make abandoned and inactive mines, 

mining-related structures, and mine wastes and tailings 

a common sight throughout the district, as well as in 

the upper Beaver Creek watershed. These past mining 

activities have contributed significantly to the degradation of water quality, aquatic biological, and hydrological conditions throughout the entire Coeur d’Alene 

River Basin (Horowitz and others, 1995; Woods and 

Beckwith, 1997; Maret and MacCoy, 2002). Currently, 

U.S. Environmental Protection Agency Superfund 

investigations are underway throughout the Coeur 

d’Alene River Basin, and the U.S. Department of the 

Interior is conducting Natural Resource Damage 

Assessments and Abandoned Mine Lands (AML) 

monitoring and remediation in the basin. Remediation 

and cleanup actions require an accurate characterization of metal sources. Although many potential metal 

sources are known to exist in the upper Beaver Creek 

watershed, information was needed to sufficiently 

quantify metal inputs to the stream. 

Metal-loading studies by Cleasby and others 

(2000) and Nimick and Cleasby (2001) conducted in 

Montana streams have been useful for characterizing 

water quality and identifying metal source areas and 

pathways in historical mining areas. In these studies, 

streamflow data and metal-concentration data, collected at sites along a stream bracketing potential metal 

source areas, were used to create downstream profiles 

of metal loads. Downstream changes in metal load 

were attributed to influent sources along the stream, 

such as surface and subsurface inflows, or to instream 

geochemical reactions. By comparing loads among 

many sites, the relative magnitude of metal inputs to a 

stream from individual source areas was determined. 

Similar methods were used during this study to quantify metal loading in the upper Beaver Creek watershed. 

Purpose and Scope 

The purpose of this report is to present the results 

of a metal-loading study conducted in upper Beaver 

Creek and Carbon Creek (a major tributary to Beaver 

Creek) in Shoshone County during May and June 

2002. The results describe the streamflow and water 

quality in Beaver and Carbon Creeks, quantify metal 

loads entering Beaver and Carbon Creeks, and identify 

the predominant metal sources. Study results will assist 

resource managers in planning and conducting effective remediation efforts. 

Description of Study Area 

The study area comprised Beaver Creek, from a 

point just upstream from the Idora Mill downstream to 

the bridge crossing near Ferguson, and Carbon Creek, 

the largest tributary to Beaver Creek in the study area, 

from a point just upstream from the Carlisle Mine adit 

to the confluence with Beaver Creek (figs. 1 and 2).

The headwaters of Beaver Creek originate in the 

Coeur d’Alene National Forest and the Coeur d’Alene 

mining district at an altitude of about 5,250 ft above 

sea level. Beaver Creek is about 12 mi long and flows 

southwest toward the town of Ferguson, at which point 

it turns and flows to the northwest into the North Fork 

Coeur d’Alene River at an altitude of about 2,450 ft. At 

its headwaters, Beaver Creek is a steep, high-gradient, 

cascading mountain stream. The streambed in these 

upper reaches is composed mostly of cobbles and boulders. Just downstream from Carbon Creek, the valley 

broadens and the topography flattens. The streambed in 

these lower reaches is a mixture of gravel, cobbles, and 

boulders. During base flow, streamflow in different 

reaches throughout the watershed flows below the 

streambed substrate (hyporheic flow). 

The upper Beaver Creek watershed contains several mineshafts and adits, at least two ore mill sites (the 

Idora Mill on Beaver Creek and the Carlisle Mill on 

Carbon Creek) and numerous tailings piles (fig. 2). 

Several unnamed adits are located along the right 

streambank of Beaver Creek downstream from the 

Idora Mill. The Carlisle Mine adit is the largest adit 

in the study area and is located just upstream from the 

Carlisle Mill on Carbon Creek. Discharge from this 

adit flows directly into Carbon Creek and appears to be 

continuous. Field observations during base flow indicate that the adit contributes a substantial amount of 

the total streamflow in Carbon Creek. 

Historically, metal extraction and processing in 

the Beaver Creek watershed were relatively inefficient, 

yielding large volumes of metal-rich tailings that were 

deposited around the mill sites and in the streams. Beaver and Carbon Creeks, during high streamflow, cut 

through these tailings and transported them down-
Data Collection Methods 5

stream, causing aggradation of the stream channel, 

which is still evident throughout much of the study 

area. 

In the 1940s, an effort was made to move tailings 

to a central location near Carbon Center (fig. 2), where 

tailings were deposited in the channel of a small, 

perennial tributary to Beaver Creek. This large, threetiered tailings pile parallels Beaver Creek for approximately 800 ft and is within 25 ft of the left streambank. 

During periods of runoff, streamflow from the unnamed tributary flows onto the tailings pile, where it 

pools and subsequently seeps downward through the 

tailings. The original tributary channel is still visible 

below the tailings pile and enters the main channel of 

Beaver Creek just upstream from the confluence with 

Dobson Gulch (fig. 2). Several seeps originate along 

the length of the tributary channel and contribute a 

small amount of surface inflow to Beaver Creek. 

Acknowledgments 

The authors acknowledge with appreciation the 

many individuals who assisted in this study. The 

authors thank Ray TeSoro of the U.S. Department of 

Agriculture, Forest Service (USFS), and Steve Box of 

the U.S. Geological Survey (USGS) for sharing their 

knowledge of the study area. Appreciation is extended 

to Rick L. Backsen, H. Russ Christensen, Sabrina A. 

Conti, John O. Gralow, Keith L. Hein, and Kevin F. 

Kirlin of the USGS for assistance in collecting and 

processing data during this study. The USFS and the 

Bureau of Land Management (BLM) provided funding 

for this study. 

DATA COLLECTION METHODS 

Data Collection Methods 

Site Selection 

Sampling sites were selected to bracket possible 

areas of metal sources such as tributary inflows, 

ground-water seeps, mine adits, mill sites, and tailings 

or waste-rock piles. Three synoptic sampling events 

were conducted during spring 2002 to represent different hydrologic conditions. Synoptic samples are those 

collected in a short amount of time to reduce the effect 

of chemical changes caused by diel variations in 

stream-flow. The first synoptic sampling event (S1) 

was conducted on May 9 and consisted of 8 main-stem 

sites and 4 surface-inflow sites. The second synoptic 

sampling event (S2) was conducted during May 21–23 

and consisted of 8 main-stem sites, 4 surface-inflow 

sites, and 6 shallow subsurface sites. The third synoptic 

sampling event (S3) was conducted during June 17–18 

and consisted of 8 main-stem sites, 3 surface-inflow 

sites, and 4 shallow subsurface sites. 

Streamflow 

Conventional methods of measuring channel 

cross-sectional area and flow velocity were used to 

determine streamflow (Rantz and others, 1982) at all 

sites except UBC–A1 and UBC4, which lacked sufficient depth and velocity needed to determine streamflow. A standard type AA or pygmy current meter 

attached to a top-setting, graduated wading rod was 

used to measure velocity and channel depth. Streamflow measurements were used to determine the streamflow gain or loss between surface-water sampling sites 

and, in conjunction with water-quality data, were used 

to calculate instantaneous metal loads at bracketed 

sampling sites. Streamflow data are presented in table 

1 (back of report).

Subsurface Flow 

Shallow piezometers were installed to determine 

the chemical quality of subsurface flow at several 

points within the study area. Piezometers were constructed from 0.75-in.-diameter stainless steel casing 

that was pinched shut at one end to create a driving 

point and capped at the other end. Above the driving 

point, a series of 0.125-in.-diameter holes were drilled 

into the casing to allow water to flow into the piezometer. After an area of possible subsurface flow was 

selected, a piezometer was installed into the ground by 

using a fencepost driver. Water from the piezometer 

was purged with a peristaltic pump, equipped with 

acid-washed tygon tubing, until the purged water was 

clear. After the well was allowed to recover, the water 

level was measured. Water-level measurements are 

presented in table 1. 

Synoptic Water-Quality Sampling 

Synoptic water samples for chemical analysis 

were collected from main-stem sites, inflows, and piezometers. Two sampling crews collected samples in 
6 Quantification of Metal Loads and Assessment of Metal Sources in Upper Beaver Creek Watershed, Shoshone County, Idaho, May and June 2002

downstream order. One crew began at the upstream 

end of Beaver Creek; the other crew began at the 

upstream end of Carbon Creek. At the confluence of 

these two creeks, the crews collected samples at alternate sites toward the downstream end of the study area. 

All samples were processed onsite.

Surface-water samples were collected in acidwashed, 3-L, polyethylene bottles at a single vertical 

near midstream. Care was taken to disrupt the streambed as little as possible between the sampling sites. 

Values of specific conductance and pH were determined onsite using an unfiltered aliquot of sample 

water. Alkalinity was determined onsite using a second 

aliquot of sample water. Water temperature was measured instream. Samples for analysis of major ions and 

trace elements were filtered through a 0.45-μm capsule 

filter preconditioned with deionized water. Aliquots for 

analysis of dissolved trace-element concentrations 

were preserved with ultra-pure nitric acid to a pH of 

less than 2. 

Subsurface-water samples from piezometers were 

collected using a peristaltic pump, equipped with acidwashed tygon tubing, to purge the volume of standing 

water until onsite measurements of water temperature, 

pH, and specific conductance stabilized and values 

were recorded. Alkalinity, major ions, and trace elements were analyzed using the same procedures and 

equipment as for surface-water samples.

Samples were processed, filtered, preserved, and 

shipped according to procedures outlined by Wilde and 

Radtke (1998) and Wilde and others (1999). Water 

samples were analyzed by the USGS Geologic Division Laboratory using methods described by Taggart 

(2002). Minimum reporting levels for major ion, nutrient, and trace-element concentrations are listed in table 

2. Selected water-quality data are presented in table 1. 

Table 2. Minimum reporting level of major ion, nutrient, and trace-element concentrations analyzed in water-quality samples from 

upper Beaver Creek watershed, Shoshone County, Idaho, May and June 2002

[mg/L, milligrams per liter; μg/L, micrograms per liter]

Constituent

Minimum 

reporting

level Constituent

Minimum 

reporting

level Constituent

Minimum 

reporting

level Constituent

Minimum 

reporting

level

Calcium, mg/L 0.05 Arsenic, μg/L 1 Iron, μg/L 50 Strontium, μg/L 0.5

Magnesium,

mg/L .01 Barium, μg/L .1

Lanthanum, 

μg/L .01 Thallium, μg/L .05

Sodium, mg/L .01 Beryllium, μg/L .05 Lead, μg/L .05 Thorium, μg/L .005

Potassium, mg/L .03 Bismuth, μg/L .005 Lithium, μg/L .1 Titanium, μg/L .1

Chloride, mg/L .08 Cadmium, μg/L .02

Manganese,

μg/L .01 Uranium, μg/L .005

Sulfate, mg/L 1.6 Cerium, μg/L .01

Molybdenum,

μg/L .2 Vanadium, μg/L .1

Fluoride, mg/L .08 Cesium, μg/L .01 Nickel, μg/L .1 Ytterbium, μg/L .01

Silica, mg/L .2 Chromium, μg/L 1 Niobium, μg/L .02 Zinc, μg/L .5

Nitrate, mg/L .08 Cobalt, μg/L .02 Rubidium, μg/L .01 Zirconium, μg/L .05

Phosphorus, 

mg/L .01 Copper, μg/L .5 Scandium, μg/L .1

Aluminum, μg/L .1 Gallium, μg/L .02 Selenium, μg/L 1

Antimony, μg/L .1

Germanium,

μg/L .02 Silver, μg/L 3
Data Collection Methods 7

Quality Assurance 

Quality assurance data to document possible sample contamination and reproducibility of analytical 

results consisted of field equipment blank samples and 

sequential replicate environmental samples (considered 

to be essentially identical in composition). To assess 

possible contamination from sampling and processing 

equipment, pre- and post-sample field equipment blank 

samples were collected and analyzed for major ion, 

nutrient, and trace-element concentrations (table 1). 

Water used for each blank was certified free of inorganic constituents and was passed through the same 

field equipment that was used to collect and process 

the environmental samples. Constituent concentrations in the blanks were all less than the minimum 

reporting level (MRL), with the exception of a zinc 

value (0.9 μg/L), which was about two times the MRL. 

A zinc concentration larger than the MRL indicates 

zinc contamination in the blank sample; however, the 

amount is small compared with zinc concentrations in 

nearly all the environmental samples. Analytical 

results for the field equipment blank samples are presented in table 1.

Two sets of replicates were collected for this 

study; one set at BC10 and one set at PBC11 (table 1). 

Precision of analytical results for a constituent can be 

described by calculating the relative percent difference 

(RPD) of the concentration in replicate sample analyses. The RPD is computed as the absolute value of the 

difference in concentration between the two replicates, 

divided by the mean concentration of the two replicates, the quotient of which is multiplied by 100. RPD 

values for constituents in the replicate samples were all 

less than 10 percent, with the exception of chloride in 

the surface-water replicate sample and fluoride in the 

subsurface-water replicate sample, indicating good 

overall precision of the analytical results. The RPD for 

chloride in the surface-water sample (BC10) was 33 

percent and, for fluoride in the subsurface replicate 

sample (PBC11), was 50 percent. These results indicate that the precision for chloride and fluoride was 

50

10

5

0.5

0.1

1

UBC3 UBC5 UBC8 BC10 BC14 CC2 CC6 CC9

200

100

10

50

5

0.5

0.1

1

STREAMFLOW, IN CUBIC FEET PER SECOND

SAMPLING SITE

CARBON

CREEK

BEAVER

CREEK

Carlisle Mine adit (CC4)

Carbon Creek (CC9)

Pioneer Gulch (PC1)

Unnamed tributary (BC12)

Dobson Gulch (DC1)

Main-stem

Surface inflow

S1—May 9

S2—May 21–23

S3—June 17–18

Downstream

Figure 3. Instantaneous streamflow at sampling sites in upper Beaver Creek and Carbon Creek watersheds, Shoshone County,

Idaho, May and June 2002.
8 Quantification of Metal Loads and Assessment of Metal Sources in Upper Beaver Creek Watershed, Shoshone County, Idaho, May and June 2002

poor and that the samples were affected by variability 

in the sample collection, laboratory imprecision, or 

both. Analytical results for replicate samples are presented in table 1. 

STREAMFLOW 

Streamflow 

Streamflow during S1 and S3 was low and stable 

with little change in flow during sample collection 

(fig. 3). Streamflow measured at the downstream mainstem sampling site (BC14) before and after surfacewater sampling increased by 4.1 and 7.3 percent during 

S1 and S3, respectively (table 1). S2 was conducted 

during a precipitation event, and streamflow was high 

and rising. Streamflow increased 53 percent during 

sample collection as a result of heavy rainfall in the 

watershed prior to and during S2. 

To identify areas that gain or lose streamflow, 

Carbon and Beaver Creeks were divided into subreaches, and streamflow was quantified within each 

subreach (figs. 4 and 5). Four subreaches were defined 

on Beaver Creek using five main-stem sites (UBC3, 

UBC5, UBC8, BC10, and BC14) that were sampled 

during S1, S2, and S3 (fig. 4). Two subreaches were 

defined on Carbon Creek using three main-stem sites 

(CC2, CC6, and CC9) that were sampled during S1, 

S2, and S3 (fig. 5). Streamflow gains or losses were 

determined as the net difference in streamflow between 

the farthest upstream and downstream sites of each 

subreach and were calculated by subtracting the 

streamflow at the farthest upstream site, plus any measured surface inflow, from the streamflow at the farthest downstream site. Consequently, a subreach can 

be identified as a losing subreach, even though streamflow might increase between the upstream and downstream sites. For example, at subreach UBC8 to BC10 

during S2 (fig. 4), the measured streamflow at the 

upstream site (UBC8) was 43.4 ft3/s, measured surface 

inflow (CC9) was 19.4 ft3/s, and measured streamflow 

at the downstream site (BC10) was 58.7 ft3/s. Even 

though there was an increase of 15.3 ft3/s between 

the upstream and downstream sites, the subreach 

would be identified as a losing subreach (–4.1 ft3/s). 

In this example, the 4.1-ft3/s streamflow loss between 

sites UBC8 and BC10 was an unaccounted loss of 

streamflow. Gains are assumed to be attributable to 

overland surface runoff, subsurface inflow, and unsampled seeps; losses are assumed to be attributable to 

hyporheic flow and ground-water recharge. 

Synoptic Sampling Event S1 

Synoptic sampling event S1 was conducted during 

low streamflow on May 9, 2002. During S1, streamflow in Beaver Creek increased by 14.7 ft3/s between 

upstream sampling site UBC3 and downstream sampling site BC14 (fig. 3; table 1). Four measured surface 

inflows (CC9, PC1, BC12, and DC1) accounted for 

about half (7.7 ft3/s) of this increase, leaving 7.0 ft3/s 

(48 percent) of the increase attributable to unsampled 

seeps and subsurface flow.

Of the four defined subreaches in Beaver Creek, 

streamflow increased in two of the subreaches and 

decreased in the other two subreaches during S1 

(fig. 4). In subreach UBC3 to UBC5, streamflow increased 1.8 ft3/s. Streamflow loss in subreach UBC5 to 

UBC8 was negligible (0.3 ft3/s). Streamflow increased 

in subreach UBC8 to BC10 by 3.2 ft3/s; however, surface inflows CC9 (4.2 ft3/s) and PC1 (0.1 ft3/s) contributed an amount of flow (4.3 ft3/s) that was larger than 

this increase, which indicates that UBC8 to BC10 was 

a losing subreach (fig. 4). Streamflow increased in subreach BC10 to BC14 by 10 ft3/s; surface inflows BC12 

(1.0 ft3/s) and DC1 (2.4 ft3/s) contributed 3.4 ft3/s, 

leaving a substantial unaccounted gain of 6.6 ft3/s 

(fig. 4). 

During S1, streamflow in Carbon Creek (the 

largest surface inflow to Beaver Creek) decreased by 

1.1 ft3/s between upstream sampling site CC2 and 

downstream sampling site CC9 (fig. 3; table 1). One 

measured surface inflow, the Carlisle Mine adit (CC4), 

contributed 0.4 ft3/s of streamflow. Of the two defined 

subreaches on Carbon Creek, streamflow decreased in 

one subreach and increased in the other (fig. 5). In subreach CC2 to CC6, streamflow decreased by 2.3 ft3/s, 

even though surface inflow CC4 contributed 0.4 ft3/s. 

Streamflow gain in subreach CC6 to CC9 was minimal 

(0.8 ft3/s). 

Synoptic Sampling Event S2 

Synoptic sampling event S2 was conducted during 

high streamflow during May 21–23, 2002. During S2, 

streamflow in Beaver Creek increased by 59.1 ft3/s 

between upstream sampling site UBC3 and downstream sampling site BC14 (fig. 3; table 1). Three 

measured surface inflows (CC9, BC12, and DC1) 

accounted for more than half (33.7 ft3/s) of this increase, leaving 25.4 ft3/s (43 percent) of the increase 
Streamflow 9

25

20

15

10

5

0

-5

1,000

800

600

400

200

0

-200

-400

UBC3–UBC5 UBC5–UBC8 BC10–BC14

4,000

3,000

2,000

1,000

0

-1,000

-2,000

-3,000

200,000

175,000

150,000

125,000

100,000

75,000

50,000

25,000

0

-25,000

-50,000

-75,000

-100,000

UBC8–BC10 UBC3–UBC5 UBC5–UBC8 BC10–BC14 UBC8–BC10

STREAMFLOW CADMIUM

LEAD

UNACCOUNTED GAIN OR LOSS OF

DISSOLVED LOAD, IN MICROGRAMS PER SECOND

UNACCOUNTED GAIN OR LOSS OF

STREAMFLOW, IN CUBIC FEET PER SECOND

ZINC

UNACCOUNTED GAIN OR LOSS OF

DISSOLVED LOAD, IN MICROGRAMS PER SECOND

SUBREACH SUBREACH

S1—May 9

S2—May 21–23

S3—June 17–18

Figure 4. Unaccounted gain or loss of streamflow and dissolved cadmium, lead, and zinc loads for each subreach in upper Beaver Creek,

Shoshone County, Idaho, May and June 2002.
10 Quantification of Metal Loads and Assessment of Metal Sources in Upper Beaver Creek Watershed, Shoshone County, Idaho, May and June 2002

1.0

0.5

0

-0.5

-1.0

-1.5

-2.0

-2.5

300

250

200

150

100

50

0

-50

-100

-150

CC2–CC6 CC6–CC9 CC2–CC6 CC6–CC9

400

300

200

100

0

-100

-200

-300

80,000

70,000

60,000

50,000

40,000

30,000

20,000

10,000

0

-10,000

-20,000

-30,000

-40,000

STREAMFLOW CADMIUM

LEAD

UNACCOUNTED GAIN OR LOSS OF

DISSOLVED LOAD, IN MICROGRAMS PER SECOND

UNACCOUNTED GAIN OR LOSS OF

STREAMFLOW, IN CUBIC FEET PER SECOND

ZINC

UNACCOUNTED GAIN OR LOSS OF

DISSOLVED LOAD, IN MICROGRAMS PER SECOND

SUBREACH SUBREACH

S1—May 9

S2—May 21–23

S3—June 17–18

Figure 5. Unaccounted gain or loss of streamflow and dissolved cadmium, lead, and zinc loads for each subreach in Carbon Creek,

Shoshone County, Idaho, May and June 2002.
Water Quality 11

attributable to overland surface runoff, unsampled 

seeps, and subsurface flow. Pioneer Gulch was dry at 

sample site PC1. 

Of the four defined subreaches in Beaver Creek, 

streamflow increased in three of the subreaches and 

decreased in one of the subreaches during S2 (fig. 4). 

Streamflow gain in subreach UBC3 to UBC5 was 6.1 

ft3/s. Streamflow gain in subreach UBC5 to UBC8 was 

minimal (0.30 ft3/s). Streamflow in subreach UBC8 to 

BC10 increased by 15.3 ft3/s; however, surface inflow 

CC9 contributed an amount of flow (19.4 ft3/s) that 

was larger than this increase, indicating that UBC8 to 

BC10 was a losing subreach (fig. 4). Streamflow gain 

in subreach BC10 to BC14 was substantial (23.1 ft3/s); 

more than half of this gain was from surface inflow 

DC1 (12.9 ft3/s). 

During S2, streamflow in Carbon Creek increased 

by 1.2 ft3/s between upstream sampling site CC2 and 

downstream sampling site CC9; most of the increase 

was in subreach CC2 to CC6. The only measured surface inflow, CC4, likely accounted for all of this increase (fig. 3; table 1). The unaccounted loss of streamflow in this subreach was negligible (fig. 5) and was 

entirely regained in subreach CC6 to CC9. 

Synoptic Sampling Event S3 

Synoptic sampling event S3 was conducted during 

low streamflow during June 17–18, 2002. During S3, 

streamflow in Beaver Creek increased 6.1 ft3/s between upstream sampling site UBC3 and downstream 

sampling site BC14 (fig. 3; table 1). The two measured 

surface inflows (CC9 and BC12) accounted for much 

of this increase (5.1 ft3/s). Pioneer Gulch was dry at 

sample site PC1 and Dobson Gulch was dry at sample 

site DC1.

Of the four defined subreaches in Beaver Creek, 

streamflow increased in two of the subreaches and 

decreased in the other two subreaches during S3 

(fig. 4). Streamflow loss was 2.1 ft3/s in subreach 

UBC3 to UBC5 and was 1.1 ft3/s in subreach UBC5 to 

UBC8. Streamflow gain in subreach UBC8 to BC10 

was substantial (8.9 ft3/s); more than half of the gain 

was from surface inflow CC9 (4.9 ft3/s), leaving an 

unaccounted gain of 4.0 ft3/s (fig. 4). Streamflow gain 

in subreach BC10 to BC14 was small (0.4 ft3/s); half of 

the gain was from surface inflow BC12 (0.2 ft3/s).

During S3, streamflow in Carbon Creek increased 

by 1.0 ft3/s between upstream sampling site CC2 and 

downstream sampling site CC9 (fig. 3; table 1); all of 

this increase can be attributed to surface inflow CC4 

(1.0 ft3/s). Even though streamflow increased in both 

subreaches of Carbon Creek, the streamflow increase 

in subreach CC2 to CC6 was less than the surface 

inflow CC4 (1.0 ft3/s), leaving an unaccounted loss 

of 0.8 ft3/s (fig. 5). The unaccounted loss in subreach 

CC2 to CC6 was entirely regained in subreach CC6 to 

CC9. 

WATER QUALITY 

Water Quality 

The synoptic samples collected during this study 

were analyzed for 45 dissolved constituents, consisting 

of major ions, nutrients, and trace elements. All 45 

constituents and minimum reporting levels (MRLs) are 

listed in table 2. Concentrations of only a few constituents were substantially greater than the MRLs. Although analysis for only the major ions, nutrients, and 

three of the trace elements (cadmium, lead, and zinc) 

are presented in table 1, the entire data set is available 

upon request to the Boise office of the U.S. Geological 

Survey (see back of title page for contact information). 

Synoptic samples for water-quality analysis were 

collected from 12 surface-water sites during S1; 12 

surface-water sites and 6 subsurface-water sites during 

S2; and 11 surface-water sites and 4 subsurface-water 

sites during S3. 

Cadmium and zinc concentrations in nearly all 

surface-water samples from Beaver Creek and Carbon 

Creek were lowest during S2 and were highest during 

S1 (figs. 6 and 7). Dilution from precipitation, surface 

runoff, and high streamflow during S2 probably decreased cadmium and zinc concentrations. Low streamflow during S1 and inflows rich in cadmium and zinc 

likely increased concentrations of these metals in 

Beaver Creek and Carbon Creek. Nearly all subsurface 

samples collected during S2 contained higher concentrations of these metals than did samples collected during S3 (fig. 8). Subsurface samples were not collected 

during S1. 

In general, concentrations of cadmium and zinc in 

Beaver Creek gradually increased between sites UBC3 

and UBC8 and sharply increased between sites UBC8 

and BC10 as a result of high concentrations in Carbon 

Creek. Concentrations of cadmium and zinc in Beaver 

Creek slightly decreased between sites BC10 and 

BC14. Lead concentrations in Beaver Creek sharply 

increased between sites UBC3 and UBC5, slightly 
12 Quantification of Metal Loads and Assessment of Metal Sources in Upper Beaver Creek Watershed, Shoshone County, Idaho, May and June 2002

UBC3 UBC5 UBC8 BC10 BC14

10

6

1

3

0.6

0.3

0.1

10

1

5

0.5

0.05

0.01

0.1

UBC3 UBC5 UBC8 BC10 BC14

3,000

1,000

100

500

50

0.5

0.1

10

5

1

UBC3 UBC5 UBC8 BC10 BC14

SAMPLING SITE

Downstream

CADMIUM LEAD

ZINC

CONCENTRATION, IN MICROGRAMS PER LITER

Carbon Creek (CC9)

Pioneer Gulch (PC1)

Unnamed tributary (BC12)

Dobson Gulch (DC1)

Carbon Creek (CC9)

Pioneer Gulch (PC1)

Unnamed tributary (BC12)

Dobson Gulch (DC1)

Carbon Creek (CC9)

Pioneer Gulch (PC1)

Unnamed tributary (BC12)

Dobson Gulch (DC1)

Main-stem concentration

Surface-inflow concentration

S1—May 9

S2—May 21–23

S3—June 17–18 

Minimum reporting level

Location of surface inflow

EXPLANATION

SAMPLING SITE

Downstream

Figure 6. Dissolved concentrations of cadmium, lead, and zinc in upper Beaver Creek, Shoshone County, Idaho, May and June

2002. (Values equal to or less than the minimum reporting level are plotted at the minimum reporting level)
Water Quality 13

CC2 CC6 CC9

10

30

60

6

1

3

0.6

0.3

0.1

40

10

4

0.4

0.1

1

CC2 CC6 CC9

20,000

10,000

1,000

5,000

500

100

CC2 CC6 CC9

SAMPLING SITE

Downstream

CADMIUM LEAD

ZINC

CONCENTRATION, IN MICROGRAMS PER LITER

SAMPLING SITE

Downstream

Carlisle Mine adit (CC4)

Carlisle Mine adit (CC4)

Carlisle Mine adit (CC4)

Main-stem concentration

Surface-inflow concentration

S1—May 9

S2—May 21–23

S3—June 17–18

Location of surface inflow

EXPLANATION

Figure 7. Dissolved concentrations of cadmium, lead, and zinc in Carbon Creek, Shoshone County, Idaho, May and June 2002.
14 Quantification of Metal Loads and Assessment of Metal Sources in Upper Beaver Creek Watershed, Shoshone County, Idaho, May and June 2002

10

30

50

6

0.1

3

0.06

0.03

0.01

2,000

1,000

3

0.3

0.1

1

6

0.6

10

10,000

6,000

1,000

3,000

600

100

60

10

6

3

1

0.6

0.3

30

300

0.1

PUBC4 PCC8 PBC11 UBC4 PBC10 PBC12 UBC-A1 PBC10A

PUBC4 PCC8 PBC11 UBC4 PBC10 PBC12 UBC-A1 PBC10A

30

300

600

60

100

1

0.6

0.3

CADMIUM LEAD

ZINC

DISSOLVED CONCENTRATION, IN MICROGRAMS PER LITER

SAMPLING SITE

Downstream

SAMPLING SITE

Downstream

S2—May 21–23

S3—June 17–18

Minimum reporting level

EXPLANATION

Figure 8. Dissolved concentrations of cadmium, lead, and zinc in subsurface water in upper Beaver Creek watershed, Shoshone

County, Idaho, May and June 2002.
Quantification of Metal Loads 15

decreased between sites UBC5 and UBC10, and then 

sharply decreased between sites BC10 and BC14 

(fig. 6). Concentrations of cadmium, lead, and zinc 

in Carbon Creek samples sharply increased between 

sites CC2 and CC6 because of inflow from the Carlisle 

Mine adit and remained fairly constant between sites 

CC6 and CC9 (fig. 7). During each of the synoptic 

sampling events, concentrations of cadmium and zinc 

were highest (28 to 41 μg/L and 6,000 to 11,300 μg/L, 

respectively) in samples collected at the Carlisle Mine 

adit (CC4) (fig. 7; table 1). During S1, the concentration of lead also was highest (21 μg/L) in the sample 

collected at the Carlisle Mine adit. During S2 and S3, 

the concentrations of lead were highest (1,300 and 

1,000 μg/L, respectively) in samples collected from a 

left-bank seep (UBC4) downgradient from the Idora 

Mill.

According to Nimick and Cleasby (2001), metals 

such as copper, magnesium, and zinc can exhibit diel 

(24-hour) variations in dissolved concentration in 

streams affected by mining activities. Results from 

their studies of streams in Montana have shown that 

maximum concentrations of these metals occurred in 

the morning; minimum concentrations occurred in late 

afternoon or evening. These diel variations in concentration can have the potential to affect the results of 

metal-loading studies. Therefore, to determine whether 

any diel variation in zinc concentration occurred during the three synoptic sampling events of this study, 

samples were collected at the downstream end of the 

study area (BC14) each morning, prior to the start of 

sampling, and again at the end of the day (table 1). 

Results of this sampling indicated that, although zinc 

concentrations did vary, no two samples varied by 

more than 2 percent (table 1). 

QUANTIFICATION OF METAL LOADS 

Quantification of Metal Loads 

Loads are calculated as the product of constituent 

concentration and streamflow. According to Cleasby 

and Nimick (2002), for stable constituents unaffected 

by chemical reactions, such as sorption, desorption, or 

volatilization, loads are additive as inflows contribute 

their load in a cumulative manner to the receiving 

stream. 

Instantaneous loads of dissolved cadmium, lead, 

and zinc were calculated for each sample collected during the three synoptic events (table 3). In cases where 

the constituent concentration was less than the MRL 

(PC1, cadmium; and DC1, lead), the MRL value was 

used to calculate the load. Downstream profiles of constituent loads are presented in figures 9 and 10. 

Table 3. Instantaneous loads of selected metals in upper Beaver 

Creek watershed, Shoshone County, Idaho, May and June 2003

[μg/s, micrograms per second]

Site

identificationSample 

date

Sample

time

(24-

hour)

Cadmium

load,

dissolved

(μg/s)

Lead 

load,

dissolved

(μg/s)

Zinc load,

dissolved

(μg/s)

Beaver Creek

UBC3

05/09

05/21

06/18

0940

1000

1045

85.9

555

404

30.6

210

690

10,700

83,500

65,000

UBC5

05/09

05/21

06/18

1045

1100

1230

181

708

381

1,430

3,420

1,560

31,400

117,000

60,200

UBC8

05/09

05/21

06/18

1200

1215

1325

254

959

402

684

4,920

1,450

44,200

165,000

64,700

BC10

105/09

105/09

05/21

06/18

1350

1355

1430

1500

915

915

2,990

1,640

744

744

5,980

2,220

212,000

215,000

673,000

338,000

BC14

05/09

05/09

05/21

05/21

06/18

06/18

0840

1520

0910

1550

0920

1540

1,040

1,140

2,490

3,860

1,180

1,260

377

364

1,720

3,810

682

732

248,000

260,000

580,000

874,000

244,000

258,000

Carbon Creek

CC2

05/09

05/21

06/18

1010

1130

1040

180

381

83.9

195

412

155

48,300

97,900

19,500

CC4

05/09

05/21

06/18

1110

1230

1125

464

1,390

793

238

610

481

128,000

360,000

170,000

CC6

05/09

05/21

06/18

1210

1320

1215

539

1,750

755

221

1,090

383

161,000

428,000

174,000

CC9

05/09

05/21

06/18

1300

1315

1250

809

1,700

902

488

1,040

569

230,000

427,000

212,000

Pioneer Gulch

PC1 05/09 1315 .14 .11 000,001.98

Unnamed tributary to Beaver Creek

BC12

05/09

05/21

06/18

1420

1545

1445

108

139

12.5

11.3

11.9

1.13

35,400

43,600

3,400

Dobson Gulch

DC1 05/09 1500 8.80 3.40 1,850
16 Quantification of Metal Loads and Assessment of Metal Sources in Upper Beaver Creek Watershed, Shoshone County, Idaho, May and June 2002

UBC3 UBC5 UBC8 BC10 BC14

5,000

1,000

3,000

600

300

100

50

60

10,000

1,000

5,000

500

50

10

100

UBC3 UBC5 UBC8 BC10 BC14

1,000,000

100,000

500,000

300,000

30,000

5,000

50,000

10,000

UBC3 UBC5 UBC8 BC10 BC14

SAMPLING SITE

Downstream

CADMIUM LEAD

ZINC

DISSOLVED LOAD, IN MICROGRAMS PER SECOND

SAMPLING SITE

Downstream

Carbon Creek (CC9)

Pioneer Gulch (PC1)

Unnamed tributary (BC12)

Dobson Gulch (DC1)

Carbon Creek (CC9)

Pioneer Gulch (PC1)

Unnamed tributary (BC12)

Dobson Gulch (DC1)

Carbon Creek (CC9)

Pioneer Gulch (PC1)

Unnamed tributary (BC12)

Dobson Gulch (DC1)

Main-stem load

Cumulative surface-inflow load

S1—May 9

S2—May 21–23

S3—June 17–18

Location of surface inflow

EXPLANATION

Figure 9. Dissolved cadmium, lead, and zinc loads in upper Beaver Creek, Shoshone County, Idaho, May and June 2002.
Quantification of Metal Loads 17

CC2 CC6 CC9

3,000

1,000

600

300

100

50

60

2,000

1,000

300

100

600

CC2 CC6 CC9

600,000

100,000

300,000

30,000

10,000

60,000

CC2 CC6 CC9

CADMIUM LEAD

ZINC

DISSOLVED LOAD, IN MICROGRAMS PER SECOND

SAMPLING SITE

Downstream

SAMPLING SITE

Downstream

Carlisle Mine adit (CC4) Carlisle Mine adit (CC4)

Carlisle Mine adit (CC4)

Main-stem load

Cumulative surface-inflow load

S1—May 9

S2—May 21–23

S3—June 17–18

Location of surface inflow

EXPLANATION

Figure 10. Dissolved cadmium, lead, and zinc loads in Carbon Creek, Shoshone County, Idaho, May and June 2002.
18 Quantification of Metal Loads and Assessment of Metal Sources in Upper Beaver Creek Watershed, Shoshone County, Idaho, May and June 2002

Downstream load profiles for this study illustrate 

the spatial distribution of loads throughout the study 

area and are similar to profiles presented by Cleasby 

and others (2000), Nimick and Cleasby (2001), and 

Cleasby and Nimick (2002). By comparing two different types of load profiles (the main-stem load and the 

cumulative surface-inflow load), potential sources and 

losses of a targeted constituent load within a study area 

can be determined. The main-stem load represents the 

actual measurement at each main-stem sampling site. 

This load is the net result of contributions from the 

sampled surface inflows and any other unsampled 

inflow (primarily subsurface inflow and unsampled 

seeps), as well as the loss in load caused by geochemical reactions, streambed deposition, or streamflow loss 

through hyporheic flow. The cumulative surfaceinflow load is the cumulative downstream sum of all 

surface inflows that were sampled and quantified. A 

load increase is implied when the main-stem load is 

greater than the cumulative surface-inflow load. A loss 

in load is implied when the cumulative surface-inflow 

load is greater than the main-stem load.

Downstream load profiles indicate and account 

for main-stem and surface-inflow load; however, the 

profiles do not clearly indicate and account for gains or 

losses in load. To identify these unaccounted gains and 

losses, loads were quantified for each defined subreach. Gains or losses were determined by subtracting 

the load at the farthest upstream site of each subreach, 

plus any surface-inflow load, from the load at the farthest downstream site of each subreach. Unaccounted 

gains or losses in loads for cadmium, lead, and zinc in 

Beaver Creek and Carbon Creek are shown in figures 4 

and 5. These graphs identify the incremental downstream change in unaccounted metal loads in the upper 

Beaver Creek watershed. 

Cadmium

The main-stem cadmium loads in Beaver Creek 

(fig. 9) during each synoptic sampling event increased 

between upstream sampling site UBC3 and downstream sampling site BC14 from 85.9 to 1,140 μg/s 

during S1, from 555 to 3,860 μg/s during S2, and from 

404 to 1,260 μg/s during S3 (table 3). Main-stem cadmium loads increased gradually between sites UBC3 

and UBC8 during each of the synoptic sampling 

events. Main-stem cadmium loads increased substantially between sites UBC8 and BC10 during each of the 

synoptic sampling events as a result of cadmium loads 

from Carbon Creek (CC9). Carbon Creek was the largest single contributor of cadmium loads to Beaver 

Creek and accounted for 71, 45, and 72 percent of the 

total main-stem cadmium load in Beaver Creek during 

S1, S2, and S3, respectively (table 3). Main-stem cadmium loads increased between BC10 and BC14 during 

S1 and S2 and decreased between BC10 and BC14 

during S3. 

Unaccounted loads among synoptic samples were 

inconsistent, indicating that varying ground-water/surface-water relations may be a controlling factor. During S1, the main-stem cadmium load in Beaver Creek 

was higher than the cumulative surface-inflow cadmium load at sites UBC5, UBC8, and BC14, indicating 

an unaccounted gain of cadmium load between sites 

UBC3 and UBC8 and between sites BC10 and BC14 

(figs. 4 and 9). Slightly higher cumulative surfaceinflow cadmium load relative to main-stem cadmium 

load during S1 at site BC10 indicated an unaccounted 

loss of cadmium load between sites UBC8 and BC10. 

During S2, the main-stem cadmium load was higher 

than the cumulative surface-inflow cadmium load at all 

sites, indicating there were unaccounted cadmium 

gains throughout the study area. During S3, the mainstem cadmium load and the cumulative surface-inflow 

cadmium load were nearly equal at all sites. However, 

during S3, the main-stem cadmium load was slightly 

higher than the cumulative surface-inflow cadmium 

load at BC10, indicating an unaccounted gain of cadmium load between sites UBC8 and BC10. At site 

BC14 during S3, the cumulative surface-inflow load 

was slightly higher than the main-stem load, indicating 

an unaccounted loss of cadmium load between sites 

BC10 and BC14 (figs. 4 and 9).

During the synoptic sampling events, the mainstem cadmium load increased substantially between 

CC2 and CC6 as a result of the cadmium loads from 

the Carlisle Mine adit (CC4). The main-stem cadmium 

loads in Carbon Creek (fig. 10) during each synoptic 

sampling event increased between upstream sampling 

site CC2 and downstream sampling site CC9 from 180 

to 809 μg/s during S1, from 381 to 1,700 μg/s during 

S2, and from 83.9 to 902 μg/s during S3 (table 3). The 

Carlisle Mine adit was the largest single contributor of 

cadmium loads to Carbon Creek and accounted for 57, 

82, and 88 percent of the total main-stem cadmium 

load in Carbon Creek during S1, S2, and S3, respectively (table 3). 
Quantification of Metal Loads 19

In general, most of the cadmium loads were 

accounted for. The main-stem cadmium load and 

cumulative surface-inflow cadmium load in Carbon 

Creek were similar during each of the synoptic sampling events (fig. 10). However, surface-inflow cadmium loads during S1 and S3 were slightly higher than 

main-stem cadmium loads at site CC6, indicating an 

unaccounted loss of cadmium load between sites CC2 

and CC6 (figs. 5 and 10). During S2, the main-stem 

cadmium load and cumulative surface-inflow cadmium 

load were very similar; only a slight unaccounted loss 

of cadmium load was indicated between sites CC6 and 

CC9. Slightly higher main-stem cadmium loads relative to surface-inflow cadmium loads during S1 and S3 

at site CC9 indicated an unaccounted gain of cadmium 

load between sites CC6 and CC9. 

Lead 

The largest unaccounted changes in lead load for 

all three synoptic sampling events were between UBC3 

and UBC5 (gaining) and between BC10 and BC14 

(losing). The main-stem lead loads in Beaver Creek 

(fig. 9) during each synoptic event increased between 

upstream sampling site UBC3 and downstream sampling site BC14 from 30.6 to 364 μg/s during S1, from 

210 to 3,810 μg/s during S2, and from 690 to 732 μg/s 

during S3 (table 3). Main-stem lead loads increased 

between sites UBC3 and UBC5 during all three synoptic sampling events, most notably during S1 and S2. 

Main-stem lead loads were higher than the cumulative 

surface-inflow lead loads during all three synoptic 

sampling events, indicating an unaccounted gain of 

lead load between sites UBC3 and UBC5 (figs. 4 and 

9). During S1, main-stem lead loads gradually decreased downstream from UBC5, indicating unaccounted losses of lead load between sites UBC5 and 

BC14. During S2 and S3, main-stem lead loads generally increased between sites UBC5 and BC10. Mainstem lead loads during each synoptic sampling event 

decreased between sites BC10 and BC14. Cumulative 

surface-inflow lead loads were higher than main-stem 

lead loads at BC14 during S1 and S3, indicating an 

unaccounted loss of lead load (figs. 4 and 9).

The main-stem lead loads in Carbon Creek 

(fig. 10) during each synoptic sampling event 

increased between upstream sampling site CC2 and 

downstream sampling site CC9 from 195 to 488 μg/s 

during S1, from 412 to 1,040 μg/s during S2, and from 

155 to 569 μg/s during S3 (table 3). The increase in 

main-stem lead load was largest between sites CC6 and 

CC9 during S1 and between sites CC2 and CC6 during 

S2 and S3. Cumulative surface-inflow lead loads were 

higher than main-stem lead loads at CC6 during S1 and 

S3, indicating an unaccounted loss of lead load between sites CC2 and CC6 (figs. 5 and 10). Main-stem 

lead loads were higher than cumulative surface-inflow 

loads at CC9 during S1 and S3, indicating an unaccounted gain of lead load between sites CC6 and CC9. 

Zinc

The main-stem zinc loads in Beaver Creek (fig. 9) 

during each of the synoptic sampling events increased 

substantially between upstream sampling site UBC3 

and downstream sampling site BC14 from 10,700 to 

260,000 μg/s during S1, from 83,500 to 874,000 μg/s 

during S2, and from 65,000 to 258,000 μg/s during S3 

(table 3). The load profile for zinc is proportionally 

similar to the load profile for cadmium. As with cadmium, the main-stem zinc load increased gradually 

between sites UBC3 and UBC8 during each of the synoptic sampling events, then increased substantially 

between sites UBC8 and BC10 as a result of zinc loads 

from Carbon Creek (CC9). Carbon Creek was the largest single contributor of zinc loads to Beaver Creek and 

accounted for 89, 49, and 82 percent of the total mainstem zinc load in Beaver Creek during S1, S2, and S3, 

respectively (table 3). Main-stem zinc loads increased 

between BC10 and BC14 during S1 and S2 and 

decreased between BC10 and BC14 during S3.

During S1, the main-stem zinc load in Beaver 

Creek was higher than the cumulative surface-inflow 

zinc load at site UBC8, indicating an unaccounted gain 

of zinc load between sites UBC3 and UBC8, whereas 

higher cumulative surface-inflow zinc load relative to 

main-stem zinc load at site BC10 indicated an unaccounted loss of zinc load between sites UBC8 and 

UBC10 (fig. 9). During S2, the main-stem zinc load 

was higher than the cumulative surface-inflow zinc 

load at all sites, indicating that there were unaccounted 

gains of zinc load throughout the study area. During 

S3, the main-stem zinc load and the cumulative surface-inflow zinc load were nearly equal at all sites. 

However, during S3, the main-stem zinc load was 

slightly higher than the cumulative surface-inflow zinc 

load at BC10, indicating an unaccounted gain of zinc 

load between sites UBC8 and BC10. At site BC14 dur-
20 Quantification of Metal Loads and Assessment of Metal Sources in Upper Beaver Creek Watershed, Shoshone County, Idaho, May and June 2002

ing S3, the cumulative surface-inflow zinc load was 

slightly higher than the main-stem zinc load, indicating 

an unaccounted loss of zinc load between sites BC10 

and BC14 (figs. 4 and 9). 

Similar to cadmium, the main-stem zinc load 

increased substantially between CC2 and CC6 during 

each of the synoptic sampling events as a result of the 

zinc loads from the Carlisle Mine adit (CC4). The 

main-stem zinc loads in Carbon Creek (fig. 10) during 

each synoptic sampling event increased between 

upstream sampling site CC2 and downstream sampling 

site CC9 from 48,300 to 230,000 μg/s during S1, from 

97,900 to 427,000 μg/s during S2, and from 19,500 to 

212,000 μg/s during S3 (table 3). The Carlisle Mine 

adit was the largest single contributor of zinc loads to 

Carbon Creek and accounted for 56, 80, and 88 percent 

of the total main-stem zinc load in Carbon Creek during S1, S2, and S3, respectively (table 3).

In general, the main-stem zinc load and cumulative surface-inflow zinc load in Carbon Creek were 

similar during each of the synoptic sampling events 

(fig. 10). However, surface-inflow zinc loads during all 

synoptic sampling events were slightly higher than 

main-stem zinc loads at site CC6, indicating an unaccounted loss of zinc load between sites CC2 and CC6 

(figs. 5 and 10). During S2, the main-stem zinc load 

and cumulative surface-inflow zinc load were very 

similar, indicating only a slight unaccounted loss of 

zinc load between sites CC6 and CC9. Higher mainstem zinc loads relative to surface-inflow zinc loads 

during S1 and S3 at site CC9 indicated an unaccounted 

gain of zinc load between sites CC6 and CC9. 

ASSESSMENT OF METAL SOURCES 

Assessment of Metal Sources 

Metal sources for Beaver Creek and Carbon Creek 

can be assessed from load profiles (figs. 9 and 10), subreach load gains and losses (figs. 4 and 5), and subsurface metal concentrations (fig. 8). In general, metal 

sources in the lower half of the Beaver Creek watershed between sites UBC8 and BC14 contributed more 

cadmium and zinc than did metal sources in the upper 

half of the Beaver Creek watershed between sites 

UBC3 and UBC8. In contrast, metal sources in the 

upper half of the Beaver Creek watershed contributed 

more lead than did metal sources in the lower half of 

the watershed. For Carbon Creek, the Carlisle Mine 

adit is the primary metal source. 

Cadmium 

Starting upstream, the first major source area for 

Beaver Creek is near the Idora Mill (between sites 

UBC3 and UBC5). On the basis of unaccounted 

gains of streamflow and cadmium load in this subreach (fig. 4) and large subsurface concentrations of 

cadmium (22 and 15 μg/L at UBC4; 6.3 and 5.7 μg/L 

at PUBC4) downgradient from the Carlisle Mill (fig. 8; 

table 1), it is likely that subsurface flow discharging to 

Beaver Creek is the source of cadmium between sites 

UBC3 and UBC5. 

Moving downstream, the next source area is in the 

subreach from the Idora Mill to the confluence with 

Carbon Creek (between sites UBC5 and UBC8). The 

source of cadmium in this subreach is unclear. A lack 

of surface inflows, no unaccounted streamflow gains, 

and a low subsurface concentration of cadmium (<0.02 

μg/L at UBC–A1, table 1) make it difficult to determine the source. Further study in this subreach would 

be needed to fully assess the cadmium source in this 

part of the study area. 

Moving farther downstream (between sites UBC8 

and BC10), the next source of cadmium is Carbon 

Creek (CC9), which, during each of the synoptic sampling events, was the primary source of cadmium to 

Beaver Creek (fig. 9). Between sites BC10 and BC14, 

a substantial source area, second only to Carbon Creek, 

is the area downgradient from the large, tiered flotation 

tailings pile near Carbon Center. Unaccounted gains in 

cadmium load and streamflow in this area (fig. 4) and 

large subsurface concentrations of cadmium (8.8 μg/L 

at PBC10, fig. 8; table 1) downgradient from the tailings pile indicate that most of the cadmium in the 

lower end of the study area is attributable to subsurface 

flow through the tailings into Beaver Creek. However, 

this area appears to be a contributor of cadmium only 

when subsurface flow is discharging to Beaver Creek. 

When subsurface flow is no longer discharging to Beaver Creek (as evident during S3 by the greater depth to 

water in the piezometers, table 1), this area no longer 

is a source area but appears to become an area of cadmium loss (fig. 4). 

In the upper subreach (between sites CC2 and 

CC6) of Carbon Creek, the Carlisle Mine adit (CC4) 

is the largest source of cadmium to Carbon Creek and, 

subsequently, to Beaver Creek (fig. 10). The source of 

cadmium in the lower subreach (between sites CC6 

and CC9) is less obvious. Unaccounted losses of 

streamflow in the upper subreach in Carbon Creek and 
Assessment of Metal Sources 21

unaccounted gains of streamflow in the lower subreach 

(fig. 5) indicate that streamflow becomes hyporheic 

flow in the upper subreach and partially returns to 

streamflow in the lower subreach. Large subsurface 

concentrations of cadmium (4.0 μg/L at PCC8 during 

S2 and S3, fig. 8; table 1) downgradient from the Carlisle Mill (fig. 2) and in the flowpath of the hyporheic 

flow indicate that the source of cadmium in the lower 

subreach of Carbon Creek may be attributable to the 

resurfacing cadmium-enriched hyporheic flow (possibly originating from the Carlisle Mine adit or the Carlisle Mill). 

Lead 

The processes controlling lead transport appear to 

be related to streamflow. Lead tends to adsorb to sediment particles and be deposited on the streambed when 

streamflow velocities are low. Higher streamflows and, 

thus, higher velocities, can remobilize lead-enriched 

particulate matter that has been deposited on the streambed and transport it downstream. Water-quality 

samples collected during high streamflow can appear 

to be enriched in dissolved lead that is actually colloidal because dissolved concentrations are operationally 

defined as the filtrate passing through a 0.45-μm filter 

pore size; thus, any lead-enriched, fine-grained particulates (<0.45 μm) would be included in the filtrate. 

Therefore, amounts of lead contributed by source areas 

to Beaver Creek and Carbon Creek vary with streamflow conditions. 

Consequently, during high streamflow (during 

S2), a major source of lead to Beaver Creek through 

the study area is the remobilization of lead-enriched 

particulate matter that has accumulated on the streambed. During low streamflow (during S1), the major 

source of lead to Beaver Creek is near the Idora Mill 

(between sites UBC3 and UBC5). Unaccounted gains 

of lead load and streamflow (fig. 4) and large subsurface lead concentrations (1,300 and 1,000 μg/L at 

UBC4 and 61 and 27 μg/L at PUBC4, fig. 8; table 1) 

downgradient from the Idora Mill indicate that the 

source of lead in this subreach is attributable to seepage of subsurface water into Beaver Creek. 

As with cadmium, during each of the synoptic 

sampling events, Carbon Creek is a major source of 

lead to Beaver Creek. As with Beaver Creek, source 

areas of lead to Carbon Creek vary with streamflow. At 

higher streamflows (during S2), increased loads from 

the Carlisle Mine adit (CC4) appear to be the largest 

source of lead to Carbon Creek (fig. 10). However, at 

lower streamflows (during S1), resurfacing leadenriched hyporheic flow appears to be the major source 

of lead to Carbon Creek (fig. 5). 

Zinc 

Sources of zinc to Beaver Creek are generally 

similar to sources of cadmium to Beaver Creek (fig. 9). 

However, large concentrations and subsequent large 

loads of zinc at site UBC3 indicate sources of zinc 

upstream from and outside of the study area. Assessing 

these sources would require further study and extension of the existing study area. 

Moving downstream, the next major source area 

for Beaver Creek is near the Idora Mill (between sites 

UBC3 and UBC5). On the basis of unaccounted gains 

of streamflow and zinc load in this subreach (fig. 4) 

and large subsurface concentrations of zinc (5,190 and 

3,200 μg/L at UBC4; 1,720 and 1,340 μg/L at PUBC4) 

downgradient from the Idora Mill (fig. 8; table 1), it is 

likely that subsurface flow discharging to Beaver 

Creek is the source of zinc between sites UBC3 and 

UBC5. 

The next downstream source area is in the subreach from the Idora Mill to the confluence with Carbon Creek (between UBC5 and UBC8). As with cadmium, the source of the zinc in this subreach is unclear, 

and further study would be needed to assess the source 

of this zinc. 

Between sites UBC8 and BC10, the next and largest source of zinc to Beaver Creek is Carbon Creek 

(CC9). Between sites BC10 and BC14, a substantial 

source of zinc, second only to Carbon Creek, is the 

area downgradient from the flotation tailings pile near 

Carbon Center. Unaccounted gains in zinc load and 

streamflow in this subreach (fig. 4) and large subsurface concentrations of zinc (1,490 μg/L at PBC10; 

1,890 and 1,700 μg/L at PBC10A, fig. 8; table 1) 

downgradient from the tailings pile indicate that most 

of the zinc loading in the lower end of the study area is 

attributable to the subsurface flow of water through the 

tailings pile at Carbon Center and the subsequent discharge of this water into Beaver Creek. As with cadmium, this area appears to be a contributor of zinc load 

only when subsurface flow is discharging to Beaver 

Creek (fig. 4). 
22 Quantification of Metal Loads and Assessment of Metal Sources in Upper Beaver Creek Watershed, Shoshone County, Idaho, May and June 2002

The Carlisle Mine adit (CC4) in the upper subreach (between sites CC2 and CC6) is the largest 

source of zinc loading to Carbon Creek and, subsequently, to Beaver Creek (fig. 10). Resurfacing 

hyporheic flow (possibly originating from the Carlisle 

adit or the Carlisle Mill) is likely the source of zinc to 

Carbon Creek in the lower subreach (between sites 

CC6 and CC9). As with cadmium, large subsurface 

concentrations of zinc (929 and 805 μg/L at PCC8, fig. 

8; table 1) downgradient from the Carlisle Mill (fig. 2) 

and in the flowpath of the hyporheic flow indicate that 

the source of zinc in the lower subreach of Carbon 

Creek may be attributable to resurfacing zinc-enriched 

hyporheic flow. 

SUMMARY

Summary

The upper Beaver Creek watershed, located in the 

Coeur d’Alene River Basin in northern Idaho, has been 

heavily impacted by the dispersion of metal-enriched 

materials from mining activities over more than 100 

years. This report describes streamflow and water quality, quantifies metal loading within the upper Beaver 

Creek watershed, and identifies metal source areas. 

Results of this study will assist resource managers in 

planning and conducting effective remediation efforts. 

A synoptic water-quality sampling approach was used 

to assess the effects of surface and shallow subsurface 

water on the gain or loss of streamflow and metal loads 

in the upper Beaver Creek watershed.

This metal-loading study consisted of three synoptic water-quality sampling events (S1, S2, and S3) 

conducted during May and June 2002. Streamflow during S1, conducted May 9, and during S3, conducted 

June 17–18, was low and stable. Streamflow during S2, 

conducted May 22–23, was high and rising. In general, 

concentrations of dissolved cadmium, lead, and zinc 

during S1 and S3 were higher than those during S2. 

Surface runoff and high streamflow during S2 contributed to the dilution of cadmium and zinc concentrations in surface-water samples. 

Main-stem concentrations of cadmium and zinc in 

Beaver Creek gradually increased downstream 

between sites UBC3 and UBC8 and sharply increased 

between sites UBC8 and BC10 as a result of high concentrations in Carbon Creek. Concentrations of cadmium and zinc slightly decreased between BC10 and 

BC14. Lead concentrations in Beaver Creek sharply 

increased between sites UBC3 and UBC5, slightly 

decreased between UBC5 and BC10, and then sharply 

decreased between sites BC10 and BC14. Concentrations of cadmium, lead, and zinc in Carbon Creek samples sharply increased between sites CC2 and CC6 and 

remained fairly constant between sites CC6 and CC9. 

During each of the synoptic sampling events, concentrations of cadmium and zinc were highest (28 to 41 

μg/L and 6,000 to 1,300 μg/L, respectively) in samples 

collected at the Carlisle Mine adit (CC4). During S1, 

the concentration of lead also was highest (21 μg/L) in 

the sample collected at the Carlisle Mine adit. During 

S2 and S3, the concentration of lead was highest (1,300 

and 1,000 μg/L, respectively) in samples collected 

from a left-bank seep (UBC4) downgradient from the 

Idora Mill.

In general, main-stem cadmium and zinc loads in 

Beaver Creek gradually increased downstream 

between sites UBC3 and UBC8 and substantially 

increased between sites UBC8 and BC10 during each 

of the synoptic sampling events. Main-stem cadmium 

and zinc loads in Beaver Creek increased between sites 

BC10 and BC14 during S1 and S2 and decreased 

between sites BC10 and BC14 during S3.

Major source areas of zinc to Beaver Creek 

include unidentified sources upstream from site UBC3 

and outside the study area. Major source areas for both 

cadmium and zinc include unidentified sources downstream from the Idora Mill between sites UBC3 and 

UBC8. Substantial unaccounted metal loads in both 

these areas indicate the need for further study to determine the location, quantify the metal load, and adequately assess the impact of these sources on Beaver 

Creek. The largest identified cadmium and zinc source 

to Beaver Creek is surface inflow from Carbon Creek 

(CC9), which accounted for 45 to 72 percent of the 

main-stem cadmium load and 49 to 89 percent of the 

main-stem zinc load in Beaver Creek. Another large 

source of cadmium and zinc to Beaver Creek is subsurface flow through the tiered flotation tailings pile near 

Carbon Center (between sites BC10 and BC14) into 

Beaver Creek. However, this area appears to be a 

source of cadmium and zinc only when subsurface 

flow is discharging to Beaver Creek.

In general, main-stem lead loads in Beaver Creek 

increased downstream between sites UBC3 and UBC5 

during each of the synoptic sampling events, most 

notably during S1 and S2. During S1, main-stem lead 

loads gradually decreased downstream between sites 

UBC5 and BC10. During S2 and S3, main-stem lead 

loads generally increased between sites UBC5 and 
References Cited 23

BC10. Main-stem lead loads during each of the synoptic sampling events decreased between sites BC10 and 

BC14.

Amounts of lead contributed by source areas to 

Beaver Creek vary with streamflow conditions. During 

high streamflow, the largest source of lead to Beaver 

Creek is the remobilization of fine-grained (<0.45-

μm), lead-enriched particulates from the streambed 

throughout the study area. During low streamflow, 

bank seepage of subsurface water into Beaver Creek in 

the subreach downgradient from the Idora Mill 

(between sites UBC3 and UBC5) is the major source of 

lead to Beaver Creek. During each synoptic sampling 

event, Carbon Creek (CC9) is a major source of lead to 

Beaver Creek.

Main-stem cadmium and zinc loads in Carbon 

Creek during each synoptic sampling event increased 

substantially between sites CC2 and CC6 and, during 

S1 and S3, continued to increase downstream to site 

CC9. The Carlisle Mine adit (CC4) is the largest source 

of cadmium and zinc to Carbon Creek and, ultimately, 

to Beaver Creek, and accounted for 57 to 88 percent of 

the total main-stem cadmium load and 56 to 88 percent 

of the total main-stem zinc load in Carbon Creek during each of the synoptic sampling events. Another 

source of cadmium and zinc to Carbon Creek is resurfacing cadmium- and zinc-enriched hyporheic flow 

(possibly originating from the Carlisle Mine adit or the 

Carlisle Mill) between sites CC6 and CC9. 

The largest increase in main-stem lead load in 

Carbon Creek occurred between sites CC6 and CC9 

during S1 and between sites CC2 and CC6 during S2 

and S3. As with Beaver Creek, amounts of lead contributed to Carbon Creek by source areas vary with 

streamflow conditions. During high streamflows, 

increased loads from the Carlisle Mine adit appear to 

be the largest source of lead to Carbon Creek and, during low streamflows, resurfacing lead-enriched 

hyporheic flow appears to be the major source of lead 

to Carbon Creek. 

REFERENCES CITED 

References Cited 

Cleasby, T.E., and Nimick, D.A., 2002, Streamflow, 

water quality, and quantification of metal loading 

in the upper Tenmile Creek watershed, Lewis and 

Clark County, west-central Montana, September 

1998: U.S. Geological Survey Water-Resources 

Investigations Report 02–4072, 64 p. 

Cleasby, T.E., Nimick, D.A., and Kimball, B.A., 2000, 

Quantification of metal loads by tracer-injection 

and synoptic-sampling methods in Cataract Creek, 

Jefferson County, Montana, August 1997: U.S. 

Geological Survey Water-Resources Investigations Report 00–4237, 39 p. 

Horowitz, A.J., Elrick, K.A., Robbins, J.A., and Cook, 

R.B., 1995, Effect of mining and related activities 

on the sediment trace element geochemistry of 

Lake Coeur d’Alene, Idaho, USA, part II—subsurface sediments: Hydrological Processes, v. 9, 

no. 2, p. 35–54. 

Maret, T.R., and MacCoy, D.E., 2002, Fish assemblages and environmental variables associated 

with hard-rock mining in the Coeur d’Alene River 

Basin, Idaho: Transactions of the American Fisheries Society, v. 131, no. 5, p. 865–884. 

Nimick, D.A., and Cleasby, T.E., 2001, Quantification 

of metal loads by tracer injection and synoptic 

sampling in Daisy Creek and the Stillwater River, 

Park County, Montana, August 1999: U.S. Geological Survey Water-Resources Investigations 

Report 00–4261, 51 p. 

Rantz, S.E., and others, 1982, Measurement and computation of streamflow: Volume 1. Measurement 

of stage and discharge: U.S. Geological Survey 

Water-Supply Paper 2175, 284 p. 

Taggart, J.E., ed., 2002, Analytical methods for chemical analysis of geologic and other materials: U.S. 

Geological Survey Open-File Report 02–223, 

[variously paged]. 

Wilde, F.D., and Radtke, D.B., eds., 1998, Field measurements, Chap. A6, in National field manual for 

the collection of water-quality data: U.S. Geological Survey Techniques of Water-Resources Investigations, Book 9, Handbooks for WaterResources Investigations, [variously paged]. 

Wilde, F.D., Radtke, D.B., Gibs, J., and Iwatsubo, 

R.T., eds., 1999, Collection of water samples, 

Chap. A4, in National field manual for the collection of water-quality data: U.S. Geological Survey 

Techniques of Water-Resources Investigations, 

Book 9, Handbooks for Water-Resources Investigations, [variously paged]. 

Woods, P.F., and Beckwith, M.A., 1997, Nutrient and 

trace-element enrichment of Coeur d’Alene Lake, 

Idaho: U.S. Geological Survey Water-Supply 

Paper 2485, 93 p. 
Table 1
Table 1 27

Table 1. Selected water-quality data for synoptic samples and field blank samples collected in upper Beaver Creek watershed, Shoshone County, Idaho, M[Site type: MB, main-stem Beaver Creek sampling site; P, piezometer subsurface sampling site; I, surface-inflow sampling site; MC, main-stem Carbon Crity control samples. The terms left bank and right bank refer to side of the creek viewed while looking downstream. ft3/s, cubic feet per second; ft, feet; μS

timeter; °C, degrees Celsius; mg/L, milligrams per liter; μg/L, micrograms per liter; —, not applicable; <, less than]

Site identification

Latitude Longitude

Sample

date

Sample

time

(24-hour)

Streamflow

(ft3/s)

Depth to 

water 

level 

below 

land 

surface

(ft)

Specific 

conductance

(

μS/cm)

Name General description Type 

Beaver Creek

UBC3 Beaver Creek upstream from Idora Mill MB 47°34'23" 115°52'03"

05/0905/2106/18

094010001045

5.4

3717.4

———

282322

PUBC4

Piezometer located in tailings and overburden 

approximately 50 ft southwest of Idora Mill P 47°34'22" 115°52'04"

05/2206/18

13501145

——

0.40

.42

2827

UBC4

Left-bank seep. Water seeping from tailings lining 

streambanks downstream from Idora Mill I 47°34'23" 115°52'06"

05/2206/18

14001130

——

——

4840

UBC5 Beaver Creek downstream from Idora Mill MB 47°34'21" 115°52'22"

05/0905/2106/18

104511001230

7.2

43.115.3

———

282522

UBC-A1 Unnamed mine adit downstream from Idora Mill I 47°34'10" 115°52'50" 05/21 1130 — — 195 

UBC8

Beaver Creek upstream from confluence with Carbon 

Creek MB 47°33'50" 115°53'22"

05/0905/2106/18

120012151325

6.9

43.414.2

———

302625

CC9 Carbon Creek, left-bank inflow to Beaver Creek MC/I 47°33'49" 115°53'22"

05/0905/2106/18

130013151250

4.2

19.4

4.9

———

875384

BC10

Beaver Creek downstream from Pioneer Creek, 

adjacent to tiered flotation tailings pile MB 47°33'47" 115°53'46"

105/09105/09

05/2106/18

1350135514301500

10.1—58.723.1

————

49493538

PC1 Pioneer Gulch, right-bank inflow to Beaver Creek I 47°33'48" 115°53'36" 05/09 1315 .1 — 35 
28 Quantification of Metal Loads and Assessment of Metal Sources in Upper Beaver Creek Watershed, Shoshone County, Idaho, May and June 2002

Table 1. Selected water-quality data for synoptic samples and field blank samples collected in upper Beaver Creek watershed, Shoshone County, Idaho, 

Continued

Name

Calcium, 

dissolved 

(mg/L)

Magnesium, 

dissolved

(mg/L)

Sodium, 

dissolved

(mg/L)

Potassium, 

dissolved

(mg/L)

Alkalinity

(mg/L)

Chloride,

dissolved

(mg/L)

Sulfate, 

dissolved

(mg/L)

Fluoride,

dissolved

(mg/L)

Silica, 

dissolved

(mg/L)

Nitrate, 

dissolved

(mg/L)

Phosphorus,

dissolved 

(mg/L)

Cadm

disso

(

μg

Beaver Creek—Continued

UBC3

2.82.02.1

0.57

.45.46

1.1

.94.77

0.33

.30.20

7.87.06.0

0.3

.2.08

5.84.87.0

<0.08

<.08<.08

4.93.63.0

<0.08

<.08<.08

<0.01

<.01<.01

0

PUBC4

1.61.8

.48.62

.95.86

.34.20

6.06.0

.2.1

7.38.0

<.08<.08

3.83.5

<.08<.08

<.01<.01

65

UBC4

2.01.7

.72.69

1.0

.99

.34.30

3.03.0

.2.1

1814

<.08<.08

4.13.9

.1.2

<.01<.01

2215

UBC5

2.72.02.1

.57.46.20

1.1

.93.79

.32.30.20

6.68.06.0

.2.2

<.08

6.24.86.0

<.08<.08

.1

4.83.73.0

<.08<.08<.08

<.01<.01<.01

UBC-A1 27 2.7 2.7 .41 50 .3 41 .2 5.7 <.08 <.01 <UBC8

3.02.12.1

.57.49.52

1.1

.98.81

.33.30.20

7.88.0

13

.3.2.1

6.45.06.0

<.08<.08<.08

5.03.83.1

<.08

.09

<.08

<.01<.01<.01

11

CC9

10

5.28.9

1.1

.72

1.2

1.31.11.4

.61.43.44

101012

.3.2.2

241222

<.08<.08

.09

5.03.83.9

<.08

.1.2

<.01<.01<.01

636

BC10

5.65.63.24.0

.77.77.58.73

1.21.11.0

.98

.46.46.34.31

8.68.68.08.0

.2.3.2.1

1313

7.5

11

<.08<.08<.08<.08

5.15.13.73.4

<.08<.08

.1

<.08

<.01<.01<.01<.01

3312

PC1 3.7 .72 1.3 .60 13 .3 6.4 .08 7.0 <.08 <.01 <
Table 1 29

Table 1. Selected water-quality data for synoptic samples and field blank samples collected in upper Beaver Creek watershed, Shoshone County, Idaho, M

Continued

Site identification

Latitude Longitude

Sample

date

Sample

time

(24-hour)

Streamflow

(ft3/s)

Depth to 

water 

level 

below 

land 

surface 

(feet)

Specific 

conductance

(

μS/cm)

Name General description Type 

Beaver Creek—Continued

PBC10

Piezometer located in flotation tailings along left 

streambank, near large, tiered flotation tailings deposit near Carbon Center P 47°33'45" 115°53'52" 05/23 0800 — 4.42 55 

PBC10A

Piezometer located in channel of unnamed tributary to 

Beaver Creek 25 ft southwest of tiered flotation tailings deposit near Carbon Center P 47°33'40" 115°53'55"

05/2306/17

08301445

——

.28.44

343372

PBC11

Piezometer located in channel of unnamed tributary to 

Beaver Creek P 47°33'39" 115°54'02"

105/23105/23

09000905

——

1.32

—

233233

PBC12

Piezometer located in channel of unnamed tributary to 

Beaver Creek P 47°33'30" 115°54'15"

05/2306/17

07301630

——

.28.63

46

118

BC12 Unnamed tributary, left-bank inflow to Beaver Creek I 47°33'30" 115°54'15"

05/0905/2106/18

142015451445

11.4

.2

———

104

9673

DC1 Dobson Gulch, left-bank inflow to Beaver Creek I 47°33'29" 115°54'18"

05/0905/21

15001530

2.4

12.9

——

58—

BC14 Beaver Creek at bridge crossing near Ferguson MB 47°33'28" 115°54'56"

205/09

05/09

205/21

05/21

206/18

06/18

084015200910155009201540

19.320.162.896.121.923.5

——————

585940404847
30 Quantification of Metal Loads and Assessment of Metal Sources in Upper Beaver Creek Watershed, Shoshone County, Idaho, May and June 2002

Table 1. Selected water-quality data for synoptic samples and field blank samples collected in upper Beaver Creek watershed, Shoshone County, Idaho, 

Continued

Name

Calcium, 

dissolved 

(mg/L)

Magnesium, 

dissolved

(mg/L)

Sodium, 

dissolved

(mg/L)

Potassium, 

dissolved

(mg/L)

Alkalinity

(mg/L)

Chloride,

dissolved

(mg/L)

Sulfate, 

dissolved

(mg/L)

Fluoride,

dissolved

(mg/L)

Silica, 

dissolved

(mg/L)

Nitrate, 

dissolved

(mg/L)

Phosphorus,

dissolved 

(mg/L)

Cadm

disso

(

μg

Beaver Creek—Continued

PBC10 4.9 0.77 1.1 0.82 31 0.2 17 <0.08 4.5 <0.08 <0.01 8.PBC10A

4446

5.45.7

1.51.5

3.53.2

6.0

41

.2.3

130120

.1.1

6.06.0

<.08<.08

<.01

.01

.

<.

PBC11

3032

3.83.8

1.31.3

2.82.9

2222

.2.2

8787

.2.1

5.25.4

<.08<.08

<.01<.01

1.1.

PBC12

4.9

13

.85

2.3

1.31.4

.55

1.3

1413

.9.2

8.8

35

.08

<.08

5.15.1

.2.2

<.01<.01

.

2.

BC12

1211

5.8

1.41.5

.87

1.21.41.2

1.51.3

.73

131410

.9.7.1

292715

<.08<.08<.08

5.95.34.3

.2.1

<.08

<.01<.01<.01

3.3.2.

DC1

6.9

—

1.2

—

1.2

—

.68

—

15—

2.7

—

8.5

—

.1

—

6.0

—

<.08

—

<.01

—

.

—

BC14

6.46.53.93.94.84.6

.87.86.83.72.97.88

1.11.11.31.11.21.1

.60.59.42.42.42.41

—111010—11

.9.9.5.5.3.3

1212

8.07.9

1111

<.08<.08<.08<.08<.08<.08

5.35.44.34.24.03.8

<.08<.08

.1.1

<.08<.08

<.01<.01<.01<.01<.01<.01

1.2.1.1.1.1.
Table 1 31

Table 1. Selected water-quality data for synoptic samples and field blank samples collected in upper Beaver Creek watershed, Shoshone County, Idaho, M

Continued

Site identification

Latitude Longitude

Sample

date

Sample

time

(24-hour)

Streamflow

(ft3/s)

Depth to 

water 

level 

below 

land 

surface 

(feet)

Specific 

conductance

(

μS/cm)

Name General description Type 

Carbon Creek

CC2

Carbon Creek upstream from Carlisle Mine adit 

discharge MC 47°33'45" 115°52'45"

05/0905/2106/18

101011301040

5.3

18.2

3.9

———

523138

CC4

Carlisle Mine adit discharge, right-bank inflow to 

Carbon Creek I 47°33'44" 115°52'56"

05/0905/2106/18

111012301125

.4

1.21.0

———

324301238

CC6

Carbon Creek downstream from Carlisle Mine adit 

discharge (upstream from Carlisle Mill) MC 47°33'44" 115°53'14"

05/0905/2106/18

121013201215

3.4

19.3

4.1

———

895085

PCC8

Piezometer located in tailings and overburden 

approximately 50 ft northwest of the Carlisle Mill P 47°33'47" 115°53'18"

05/2206/18

15001330

——

0.33

.70

8176

Field Blanks

Pre-sample field equipment blank QC — — 05/09 0810 — — —

Post-sample field equipment blank QC — 05/09 1550 — — —
32 Quantification of Metal Loads and Assessment of Metal Sources in Upper Beaver Creek Watershed, Shoshone County, Idaho, May and June 2002

Table 1. Selected water-quality data for synoptic samples and field blank samples collected in upper Beaver Creek watershed, Shoshone County, Idaho, 

Continued

1 Replicate sample.2 Sample collected for determination of diel variability only; not plotted on any figures.

Name

Calcium, 

dissolved 

(mg/L)

Magnesium, 

dissolved

(mg/L)

Sodium, 

dissolved

(mg/L)

Potassium, 

dissolved

(mg/L)

Alkalinity

(mg/L)

Chloride,

dissolved

(mg/L)

Sulfate, 

dissolved

(mg/L)

Fluoride,

dissolved

(mg/L)

Silica, 

dissolved

(mg/L)

Nitrate, 

dissolved

(mg/L)

Phosphorus,

dissolved 

(mg/L)

Cadm

disso

(

μg/

Carbon Creek—Continued

CC2

5.13.03.4

1.1

.63.80

1.51.11.2

0.48

.44.40

7.87.08.0

0.2

.2.2

13

7.0

10

<0.08

<.08<.08

4.93.94.0

0.2

.2

<.08

<0.01

<.01<.01

1.2

.7.7

CC4

464029

3.63.72.7

3.03.12.4

1.1

.96.67

424335

.2.2.2

110

9763

.1.1.1

3.53.33.0

<.08

.09.3

<.01<.01<.01

414128

CC6

11

5.39.2

1.2

.73

1.2

1.41.11.4

.61.43.43

12

7.0

14

.3.2.2

241222

<.08<.08

.1

5.03.83.8

<.08

.2.2

<.01<.01<.01

5.63.26.5

PCC8

9.89.0

1.11.2

1.61.5

.46.42

1513

.2.2

2220

.09.09

4.24.3

.3.2

<.01<.01

4.04.0

Field Blanks—Continued

<.05 <.01 <.01 <.03 — <.08 <1.6 <.08 <.2 <.08 <.01 <.0<.05 <.01 <.01 <.03 — <.08 <1.6 <.08 <.2 <.08 <.01 <.0
ation of Metal Loads and Assessment of Metal Sources in Upper Beaver Creek Watershed, Shoshone County, Idaho, May and June 2002

—

U.S. Geological Survey Water-Resources Investigations Report 03–4206

Printed on recycled paper