science for a changing world

Prepared in cooperation with 

RIO BLANCO COUNTY

Baseline Characterization of Water Quality 

and Mass Loading in Piceance Creek, 

Rio Blanco County, Colorado, 

December 2000

Water-Resources Investigations Report 02-4134

U.S. Department of the Interior 

U.S. Geological Survey
Cover Photograph:

Piceance Creek looking downstream from transport site 2. 

Field team retrieving tracer samples from automatic sampler. 

(Photograph by Sheryl A. Ferguson, U.S. Geological Survey)
Baseline Characterization of Water 

Quality and Mass Loading in Piceance 

Creek, Rio Blanco County, Colorado, 

December 2000

By Roderick F. Ortiz

U.S. GEOLOGICAL SURVEY 

Water-Resources Investigations Report 02-4134

Prepared in cooperation with 

RIO BLANCO COUNTY

Denver, Colorado 

2002
U.S. DEPARTMENT OF THE INTERIOR 

GALE A. NORTON, Secretary

U.S. GEOLOGICAL SURVEY 

Charles G. Groat, Director

The use of firm, trade, and brand names in this report is for identification purposes only and does 

not constitute endorsement by the U.S. Geological Survey.

For additional information write to:

District Chief 

U.S. Geological Survey 

Box25046, Mail Stop 415 

Denver Federal Center 

Denver, CO 80225-0046

Copies of this report can be purchased 

from:

U.S. Geological Survey 

Information Services 

Box 25286

Denver Federal Center 

Denver, CO 80225
CONTENTS

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

Introduction................................................................................................._^ 1

Purpose and Scope....................................................................................................................................................... 3

Description of Study Area ........................................................................................................................................... 5

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

Methods of Data Collection................................................................................................................................................... 7

Tracer Injection............................................................................................................................................................ 9

Supplemental Instantaneous Streamflow Measurements ............................................................................................ 10

Synoptic Sampling....................................................................................................................................................... 13

Quality Assurance........................................................................................................................................................ 14

Baseline Characterization of Water Quality .......................................................................................................................... 15

Physical Properties....................................................................................................................................................... 15

Major-Ion Concentrations............................................................................................................................................ 15

Trace-Constituent Concentrations ............................................................................................................................... 16

Tracer-Injection Results......................................................................................................................................................... 17

Synoptic Bromide Concentrations............................................................................................................................... 20

Estimation of Streamflow ............................................................................................................................................ 20

Mass Loads ..............................................................................,......../............_^ 24

Major Ions.................................................................................................................................................................... 24

Trace Constituents....................................................................................................................................................... 24

Summary................................................................................................................................................................................ 28

References Cited.................................................................................................................................................................... 29

Data Section........................................................................................................................................................................... 31

FIGURES

1. Location map of the Piceance Basin and the study area, Rio Blanco County, Colorado........................................ 2

2. Location map of injection and selected sampling sites in Piceance Creek and inflow sites to

Piceance Creek, December 4-7, 2000..................................................................................................................... 6

3-16. Graphs showing:

3. Annual hydrograph at USGS streamflow-gaging stations 09306200 and 09306222

for water year 2000......................................................................................................................................... 7

4. Injection rates and bromide concentrations from injectate samples collected during

tracer-injection study in Piceance Creek, December 4 and 5, 2000, and December 7, 2000......................... 10

5. Bromide concentrations at transport sites T5 to T8 in Piceance Creek, December 4 and 5, 2000................. 11

6. Bromide concentrations at transport sites Tl to T4 in Piceance Creek, December 6 and 7, 2000................. 12

7. Values of pH, specific conductance, and dissolved solids in Piceance Creek, December 5-7, 2000............. 16

8. Selected dissolved-cation concentrations in Piceance Creek, December 5-7, 2000...................................... 17

9. Selected dissolved-anion concentrations in Piceance Creek, December 5-7, 2000....................................... 18

10. Selected dissolved-trace-constituent concentrations in Piceance Creek, December 5-7, 2000..................... 19

11. Bromide concentrations and estimated Streamflow at synoptic sampling sites in Piceance Creek,

Decembers, 2000........................................................................................................................................... 21

12. Bromide concentrations and estimated Streamflow at synoptic sampling sites in Piceance Creek,

December 7, 2000........................................................................................................................................... 22

13. Instanneous Streamflow measurements along the primary and secondary study reaches in

Piceance Creek, December 5-7, 2000............................................................................................................ 23

14. Dissolved calcium, magnesium, and sodium loads in Piceance Creek, December 5-7, 2000....................... 25

15. Dissolved bicarbonate, sulfate, and chloride loads in Piceance Creek, December 5-7, 2000........................ 26

16. Dissolved barium, boron, and strontium loads in Piceance Creek, December 5-7, 2000.............................. 27

CONTENTS III
TABLES

1. Site locations for tracer-dilution and synoptic-sampling study in Piceance Creek, December 4-7, 2000 ............. 3

2. Sequence of events during tracer-dilution and synoptic-sampling study, September 12-14, 2000, and

Decembers-?, 2000............................................................................................................................................... 8

3. Summary of instantaneous streamflow measurements made along the primary study reach of

Piceance Creek, December 3-7, 2000..................................................................................................................... 14

4. Linear regression statistics for predicting dissolved solids and selected ion concentrations in

Piceance Creek from specific-conductance data, December 2000 ......................................................................... 16

5. Chemical data for synoptic samples collected in Piceance Creek Basin, December 4-7, 2000............................. 33

6. Comparison of selected constituent concentrations for duplicate water-quality samples collected

in Piceance Creek Basin, December 4-7, 2000 ...................................................................................................... 40

7. Water-quality data for field blanks processed December 5 and December 7, 2000................................................ 41

CONVERSION FACTORS, ABBREVIATED UNITS, AND ACRONYMS

Multiply

gram

kilogram

ton (metric)

micrometer

millimeter

meter

kilometer

milliliter

liter

square kilometer

cubic meter

liter per second

milliliter per minute

kilogram per day

By

0.03527

2.205

1.102

0.0000394

0.0394

3.281

0.6214

0.0339

0.2642

0.3861

0.000811

0.03531

0.0339

0.0011

To obtain

ounce

pound

ton (short)

inch

inch

feet

mile

ounce

gallon

square mile

acre-foot

cubic feet per second

ounce per minute

ton per day

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

°F = 9/5°C + 32

Sea level: In this report, "sea level" refers to the National Geodetic Vertical Datum of 1929 (NGVD of 1929) a geodetic datum derived 

from a general adjustment of the first-order level nets of both the United States and Canada, formerly called Sea Level Datum of 1929.

Specific conductance is given in microsiemens per centimeter at 25 degrees Celsius (fiS/cm at 25 °C).

Concentrations of chemical constituents in water are given either in milligrams per liter (mg/L) or micrograms per liter (|ig/L).

ABBREVIATED UNITS USED IN THIS REPORT

L/s liter per second 

s.u. standard units 

pCi/L picocurie per liter

IV CONTENTS
ACRONYMS USED IN THIS REPORT

BLM Bureau of Land Management

USGS U.S. Geological Survey

RPR Relative percent difference

NWQL National Water Quality Laboratory

NaBr Sodium Bromide

LiBr Lithium Bromide

CONTENTS

Baseline Characterization of Water Quality and Mass 

Loading in Piceance Creek, Rio Blanco County, 

Colorado, December 2000

By Roderick F. Ortiz

ABSTRACT

Data collected by the U.S. Geological Survey 

provided a baseline characterization of the water 

quality in Piceance Creek and quantified the mass load 

for selected chemical constituents in Piceance Creek 

during base-flow conditions. Tracer-dilution techniques and instantaneous measurements were used to 

determine streamflow in Piceance Creek. Synopticsampling techniques were used to determine baseline 

concentrations for selected constituents. Load profiles 

along subreaches of the creek were generated by 

combining tracer-dilution and synoptic-sampling 

techniques.

Data collected as part of this study provide an 

updated characterization of the water quality in 

Piceance Creek along the 28-kilometer study reach. In 

1987, bicarbonate, sulfate, and sodium were reported 

as the principal dissolved constituents in Piceance 

Creek. The principal dissolved constituents remained 

the same in December 2000. High concentrations of 

bicarbonate and sodium result from the contact of 

ground water with evaporite minerals in the Green 

River Formation. Sulfate is commonly found in high 

concentrations in the ground water of the overlying 

Uinta Formation, Concentrations of barium, boron, 

lithium, and strontium also were elevated in Piceance 

Creek. No significant load input to Piceance Creek 

was detected along the reach adjacent to the boundary 

of the Yankee Gulch Lease (primary study reach). 

Although the area near Alkali Flat contributed 

substantially to the increase in constituent concentration in Piceance Creek, losses in streamflow resulted 

in relatively small increases in load downstream to the 

end of the study reach.

INTRODUCTION

The Piceance Creek Basin is a downwarped, 

depositional region located in northwestern Colorado 

(fig. 1). The structural basin was formed during the 

Laramide orogeny, a mountain-building process of 

thrusting, faulting, and folding that lasted at least 

10 million years from Late Cretaceous to Eocene time 

(Maclachlan, 1987). About 48 million years ago, an 

ancient lake (Lake Uinta) covered thousands of square 

kilometers of Colorado, Utah, and Wyoming. At its 

maximum size, Lake Uinta covered about 

57,000 square kilometers, including the Piceance 

structural basin. Vast quantities of oil shale accumulated as organic-rich marls in the deeper part of the 

lake. Evaporite minerals such as sodium, bicarbonate, 

and chloride also precipitated in the oil-rich 

marlstones as brine concentrations exceeded the 

solubility limits of these minerals. When downwarping 

ceased, the basin filled with sediments and Lake Uinta 

disappeared (Dyni, 1987).

The marl stone of the Green River Formation in 

the Piceance Basin is a repository for one of the largest 

energy reserves in the world (Donnell, 1987). For 

nearly a century, the area has been known for its rich 

oil-shale deposits. From 1950 to 1990, concentrated 

efforts were made by the federal government and the 

oil industry to locate and develop the oil-shale reserves 

as alternative energy sources. These efforts were never 

fully realized.

Other potentially valuable minerals also are 

abundant in the oil-shale deposits. Nahcolite, a sodium 

bicarbonate mineral; dawsonlte, a sodium aluminum 

carbonate mineral; and halite, sodium chloride, are 

interspersed through the lower part of the oil-shale 

deposits. In recent years, the emphasis of resource 

development in the Piceance Creek Basin has turned to

ABSTRACT
108 30' 108

40°

39°30'

Hydrology modified by Denver Water Board 1998

from U.S. Geological Survey Digital Line Graphs 1:100,000, 1981-82.

Albers Equal-Area projection

Standard parallels 37'30'N and 40'30'N

Central Meridian 105"30'W

0 5 10 15 20 KILOMETERS

I____i____|____i____|__________

10 15 20 MILES

COLORADO

 Meeker

 Denver

i x- .. 

Grand

Junction Piceance Creek 

Basin ,09306200

EXPLANATION

APPROXIMATE EXTENT OF STUDY AREA 

APPROXIMATE BOUNDARY OF YANKEE GULCH LEASE 

BASIN BOUNDARY

U.S. GEOLOGICAL SURVEY GAGING STATIONS-Number 

indicates station identification

Figure 1. Location of the Piceance Basin and the study area, Rio Blanco County, Colorado.

2 Baseline Characterization of Water Quality and Mass Loading in Piceance Creek, Rio Blanco County, Colorado, December 2000
commercial nahcolite solution mining for sodium 

bicarbonate (baking soda) and sodium carbonate (soda 

ash). The Piceance Basin is reported to have the largest 

and most economically significant nahcolite resources 

in the world (Beard and others, 1974). Conservative 

estimates of in-place nahcolite have been reported at 

26 billion metric tons.

In 1999, the U.S. Bureau of Land Management 

(BLM) issued a Draft Environmental Impact Statement that evaluated the effects of a commercial 

nahcolite solution mining operation on the Yankee 

Gulch Joint-Venture Lease (fig. 1) within the BLM's 

White River Resource Area (U.S. Bureau of Land 

Management, 1999). The Yankee Gulch Sodium 

Minerals Project (Yankee Gulch Project) would occur 

at this site about 37 kilometers southwest of Meeker, 

Colorado (fig. 1). As part of the permitting and regulatory requirements, the mine operators were required to 

submit a monitoring plan that, in part, would characterize the baseline water quality in the adjacent 

Piceance Creek (Agapito Associates, Inc., 1999). The 

primary objective of the baseline characterization, of 

which this study is a part, is to provide the baseline 

data needed to assess possible changes in the water 

quality of Piceance Creek due to continued mining

operations. The U.S. Geological Survey (USGS) 

provided this characterization in cooperation with Rio 

Blanco County, Colorado.

Purpose and Scope

The purpose of this report is to (1) provide a 

baseline characterization of the water quality in 

Piceance Creek, and (2) quantify the mass load for 

selected chemical constituents in Piceance Creek 

during base-flow conditions. Physical and chemical 

data were collected during the week of 

December 3-8, 2000, at 47 main-stem sites and 4 

inflow sites (table 1). Several quality-assurance 

samples also were collected. The study reach extended 

about 28 kilometers between the USGS streamflowgaging stations 09306200 (Ryan Gulch station, PCO) 

and 09306222 (White River station, PC28,348) on 

Piceance Creek (fig. 1). The primary focus of the study 

was along the approximately 11.5 kilometers of the 

study area adjacent to the lease boundary for the 

Yankee Gulch Project (primary study reach).

Table 1. Site locations for tracer-dilution and synoptic-sampling study in Piceance Creek, December 4-7, 2000

[s.u., standard units; uS/cm, microsiemens per centimeter; °C, degrees Celsius; USGS, U.S. Geological Survey; Y, yes; N, no; NA, not applicable; 

e, estimated; LiBr, lithium bromide; NaBr, sodium bromide]

Site 

number

Distance from 

streamflowgaging station 

09306200 

(meters)

Sample collection

Date Time

PH 

(s.u.)

Specific 

conductance 

(uS/cm at 

25 °C)

Background 

bromide 

sample 

collected

Site type designation

PCO 12-07-00 1040

PC 180

PC420

PC660

PC 1,080

PC 1,320

PC 1,560

PC 1,960

PC2,205

PC2,445

PC2,685

PC2,925

PCS, 105

180

420

660

1,080

1,320

1,560

1,960

2,205

2,445

2,685

2,925

3,105

12-07-00

12-07-00

12-07-00

12-07-00

12-07-00

12-07-00

12-07-00

12-07-00

12-07-00

12-07-00

12-07-00

12-07-00

Main-stem Piceance Creek sites

8.0 1,540 NA

8.0

8.0

8.0

8.1

8.1

8.1

8.1

8.1

8.1

8.0

8.0

8.0

1,590

1,590

1,600

1,610

1,610

1,610

1,610

1,600

1,610

1,620

1,630

1,630

N

Y

N

N

N

Y

N

Y

N

N

N

Y

Background, USGS streamflow-gaging

station 09306200, LiBr injection site

Routine, transport site Tl

Routine

Routine

Routine

Routine

Routine

Routine

Indicator, transport site T2, quality control 

Routine 

Routine 

Routine 

Routine

INTRODUCTION
Table 1. Site locations for tracer-dilution and synoptic-sampling study in Piceance Creek, December 4-7, 2000 Continued

[s.u., standard units; u.S/cm, microsiemens per centimeter; °C, degrees Celsius; USGS, U.S. Geological Survey; Y, yes; N, no; NA, not applicable; 

e, estimated; LiBr, lithium bromide; NaBr, sodium bromide]

Site 

number

Distance from 

streamflowgaging station 

09306200 

(meters)

Sample collection

Date Time

PH 

(S.U.)

Specific 

conductance 

(uS/cm at 

25 °C)

Background 

bromide 

sample 

collected

Site type designation

Main-stem Piceance Creek sites Continued

PC3,278

PC3,505

PC3J35

PC3,935

PC4,180

PC4,420

PC4,660

PC4,900

PCS, 040

PC5,280

PC6,625

PC6,813

PC7,028

PC7,248

PC7,498

PC7J38

PC7,978

PC8,098

PC8,448

PC8,688

PC8,938

PC9,298

PC9,608

PC9,938

PC10,328

PC 10,748

PC 11, 483

PC 14,789

PC16,210

PC17,860

PC20J08

PC23J21

PC24J87

PC28,348

3,278

3,505

3,735

3,935

4,180

4,420

4,660

4,900

5,040

5,280

6,625

6,813

7,028

7,248

7,498

7,738

7,978

8,098

8,448

8,688

8,938

9,298

9,608

9,938

10,328

10,748

11,483

14,789

16,210

17,860

20,708

23,721

24,787

28,348

12-07-00

12-07-00

12-07-00

12-07-00

12-07-00

12-07-00

12-07-00

12-07-00

12-07-00

12-07-00

12-05-00 

12-07-00

12-05-00

12-05-00

12-05-00

12-05-00

12-05-00

12-05-00

12-05-00

12-05-00

12-05-00

12-05-00

12-05-00

12-05-00

12-05-00

12-05-00

12-05-00

12-05-00

12-06-00

12-06-00

12-06-00

12-06-00

12-06-00

12-06-00

12-06-00

0845

0835

0825

0815

0800

0755

0745

0735

0727

0700

1040 

1147

1020

1010

0955

0945

0935

0930

0915

0905

0855

0850

0825

0815

0805

0800

0745

0730

1005

0910

0805

1030

0945

0900

0745

8.0

8.0

8.1

8.1

8.0

8.0

8.0

8.0

8.1

8.0

8.0 

8.1

8.0

8.0

8.0

8.0

8.0

8.0

8.1

8.0

8.0

8.0

8.0

8.0

8.0

8.0

8.0

8.1

8.0

8.0

8.1

8.0

8.0

7.9

8.0

1,630

1,640

1,650

1,640

1,630

1,630

1,630

1,640

1,630

1,590

1,680 

1,690

1,690

1,690

1,700

1,680

1,690

1,710

1,700

1,720

1,730

1,720

1,720

1,700

1,740

1,730

1,730

1,720

1,780

1,770

1,710

1,730

1,980

1,950

1,980

N

Y

N

Y

Y

N

Y

N

N

N

Y

N

Y

Y

Y

N

Y

N

Y

Y

Y

Y

Y

Y

Y

Y

Y

Y

NA

NA

NA

NA

NA

NA

NA

Routine

Routine, quality control

Routine

Routine

Indicator, transport site T3

Routine

Routine

Routine

Routine

Indicator, transport site T4

Background, NaBr injection site 

Quality assurance

Routine, transport site T5

Routine

Routine

Routine

Routine

Routine

Indicator, transport site T6, quality control

Routine, quality control

Routine

Routine

Routine

Routine

Routine, transport site T7

Routine

Routine

Indicator, transport site T8

Routine

Routine

Indicator

Routine

Indicator

Routine

Routine, USGS station 09306222

Inflows and springs

RGS

HGS

PT 16,225

AFS

e200

el, 625

el 6,225

e2 1,288

12-04-00

12-07-00

12-06-00

12-04-00

0900

1220

0925

1225

7.8

8.0

8.0

7.8

3,060

3,510

1,150

12,700

NA

NA

NA

NA

Ryan Gulch spring

Spring contact near Hatch Gulch

Dry Fork

Alkali Flat spring contacts

Baseline Characterization of Water Quality and Mass Loading in Piceance Creek, Rio Blanco County, Colorado, December 2000
Tracer-dilution techniques were used to develop 

a spatial streamflow profile along the primary study 

reach. This reach is close to the Yankee Gulch Project, 

a nahcolite-solution mining operation that could 

possibly affect the water quality of the creek. A less 

detailed streamflow profile was developed along the 

lower two-thirds of the study reach (secondary study 

reach) by using standard USGS streamflow-measurement techniques (Rantz and others, 1982). Synoptic 

water-quality samples were collected along both study 

reaches to establish baseline constituent concentrations and to calculate mass loading in Piceance Creek.

Description of Study Area

The study area described in this report extends 

between the Ryan Gulch streamflow-gaging station 

(PCO) and the White River streamflow-gaging station 

(PC28,348) (fig. 2). Sites were identified by a downstream distance in meters from the PCO. The study 

area encompasses about 235 square kilometers of 

drainage area (Crowfoot and others, 2001). Streamchannel elevations range from 1,850 to 1,746 meters 

above sea level. The highest elevation in the study area 

is nearly 2,400 meters. Generally, streamflow 

increases downstream during base-flow conditions 

from October to April; streamflows are more similar 

during the irrigation season (fig. 3). Tobin (1987), 

however, identified a subreach downstream from Dry 

Fork where streamflow decreased. An estimated 

80 percent of the annual runoff in the watershed occurs 

during base-flow conditions, and springs are an important contributor to streamflow during this period 

(Robson and Saulnier, 1981). Most of the tributaries to 

Piceance Creek are ephemeral; Dry Fork was the only 

surface-water inflow to Piceance Creek measured 

during the December 2000 field activities (fig. 2). 

Because of the large number of sites sampled as part of 

this study, only sample sites specifically addressed in 

this report are shown in figure 2.

Piceance Creek is characterized by a meandering stream channel incised into the floodplain with 

deep bank carving that is prone to sloughing. As such, 

sediment loads to the stream can be considerable 

during high runoff (Norman, 1987). The streambed is 

composed of silt, sand, gravel, and occasional cobbles. 

Pockets of fine material are deposited where slow 

stream velocity occurs. Although lakes and reservoirs 

are not abundant in the Piceance Creek Basin, a small

irrigation/wildlife impoundment is located in the study 

reach (fig. 2). Typically, impoundments such as these 

are less than 4.5 meters in depth and are prone to siltation (U.S. Bureau of Land Management, 1984). The 

gentle slope of the stream valley provides an area well 

suited for sub-irrigated or flood-irrigated agricultural 

production. Irrigation is prevalent from May through 

mid-October in the relatively narrow (300 to 380 

meters wide) alluvial valley. The predominant crops 

are alfalfa and grass hay for livestock (U.S. Bureau of 

Land Management, 1984). The climate in the area is 

characterized by low humidity, sunny days, clear 

nights, little precipitation, extreme evaporation, and 

large diurnal temperature changes (U.S. Bureau of 

Land Management, 1984). The mean daily air temperature during December 2000 at Rifle, Colorado 

(fig. 1), ranged from -8 to 2 degrees Celsius (Colorado 

Climate Center, 2001). Stream temperatures during the 

field activities were routinely near freezing, and ice 

was observed along much of the streambank of 

Piceance Creek.

The valleys of the White River (fig. 2) and its 

tributaries are partly filled with alluvium and fan 

deposits consisting of sand and gravel. However, test 

holes drilled downstream from Ryan Gulch (fig. 1) 

penetrated about 21 meters of clay interbedded with 

sand and gravel, which indicates deposition in a lake 

environment (Welder, 1987). The frequency of occurrence of such clay beds is unknown. Downstream 

water movement in these less permeable aquifers is 

restricted, which forces the water to discharge as 

springs. Springs that maintain the streamflow 

throughout the year are found along the upper reaches 

of Piceance Creek including Ryan Gulch, where 

water-bearing marlstones of the Green River Formation intersect the valley of Piceance Creek (Saulnier 

and Ford, 1977). Springs in the area also may be 

supplied directly by water discharging from the 

bedrock aquifers through fractures (Welder, 1987). 

The complex fracture system in the Piceance Creek 

Basin has been extensively studied and is the primary 

conduit through which ground water flows through the 

bedrock aquifers of the basin (Grout and Verbeek, 

1985; Verbeek and Grout, 1983a, 1983b, and 1987).

Acknowledgments

The author acknowledges the many individuals 

who assisted in this study. Particular thanks are

INTRODUCTION
108° 18' 108 14'

40° 02'

39'58'

approximate

location of __.

irrigation

impoundment

\ *

: ;pci,96o';jfi: ;PC3,278

* -, Primary Study 

? PC5,280(T4) \ Reach

PC4yl80(T3)

>PCi/ e'o(T1)

PCO 

(09306200)

PT16.225

AFS

APPROXIMATE EXTENT 

OF STUDY AREA

APPROXIMATE BOUNDARY 

OF YANKEE GULCH LEASE

PICEANCE CREEK SAMPLING 

SITE AND NUMBER. NUMBER 

DENOTES DISTANCE 

DOWNSTREAM FROM 

U.S. GEOLOGICAL SURVEY 

GAGING STATION 09306200, IN 

METERS. SITE NUMBER IN 

PARENTHESIS INDICATES 

TRANSPORT SITE NUMBER, 

WHERE APPLICABLE

TRIBUTARY SAMPLING SITE 

AND NUMBER

SPRING SAMPLING SITE AND 

NUMBER

PCO (09306200)

PICEANCE CREEK SITE, STATION 

AND U.S. GEOLOGICAL SURVEY 

STATION IDENTIFICATION

Hydrology modified by Denver Water Board 1998

from U.S. Geological Survey Digital Line Graphs 1:100,000, 1981-82.

Albers Equal-Area projection

Standard parallels 37'30'N and 40°30'N

Central Meridian 105°30'W

3 KILOMETERS

SMILES

Figure 2. Location of injection and selected sampling sites in Piceance Creek and inflow sites to Piceance Creek, 

December 4-7, 2000.

Baseline Characterization of Water Quality and Mass Loading in Piceance Creek, Rio Blanco County, Colorado, December 2000
1,400

PCO (Piceance Creek below Ryan 

Gulch, station 09306200)

 PC28.348 (Piceance Creek at 

White River, station 09306222)

Oct Nov Dec Jan Feb Mar Apr May June July Aug Sept

Figure 3. Annual hydrograph at USGS streamflow-gaging stations 09306200 and 09306222 for 

water year 2000.

extended to George J. Saulnier, Jr., of Duke Engineering and Celina Akin of American Soda, LLP, for 

sharing their insight and knowledge of the study area. 

Individuals assisting in the collection of water-quality, 

hydrologic, or geologic data are acknowledged and 

include: Tom Young and Willard Phillips of American 

Soda, LLP and volunteer Mary Leib. The author also 

would like to acknowledge the contributions of 

Daniel L. Brendle, Russell G. Dash, Joseph R. 

Dungan, Sheryl A. Ferguson, Kenneth J. Leib, 

Robert L. Runkel, Robert W. Stogner, Sr., 

Kenneth R. Watts, and Douglas B. Yager of the USGS.

METHODS OF DATA COLLECTION

This study was designed to determine streamflow and baseline-chemical quality at numerous mainstem sites in Piceance Creek. Tracer-dilution techniques and instantaneous streamflow measurements 

were used to determine streamflow. Synopticsampling techniques were used to determine concentrations for selected constituents in Piceance Creek. 

Load profiles along subreaches of the creek were 

generated by combining tracer-dilution and synopticsampling techniques (Kimball, 1997).

A general overview of the field activities is 

described here. A more detailed account can be found 

in table 2 and in the following sections of this report. 

The study area was divided into two areas of investigation. The upper one-third of the study area (primary 

study reach) was investigated by using tracer-dilution 

and synoptic-sampling techniques. About 85 percent 

of the total sites were located along the primary study 

reach to provide a detailed understanding of the baseline concentrations near the Yankee Gulch Project. 

The primary study reach was divided further into two 

separate tracer-dilution experiments for logistical

METHODS OF DATA COLLECTION
Table 2. Sequence of events during tracer-dilution and synoptic-sampling study, September 12-14, 2000, and 

December 3-7, 2000

[NA, not applicable; NaBr, sodium bromide; LiBr, lithium bromide]

Start 

date

Approximate 

start time Activity

9-12-00 to 9-14-00 

12-03-00

12-04-00

12-05-00

12-06-00

12-07-00

NA Reconnaissance to determine location of injection sites and stream sampling sites.

0800 Collection of background bromide samples between PC6,625 and PCI 1,483.

0830 Estimation of traveltimes between PC6,625 and PCI 1,483.

1200 Preparation of NaBr solution.

1400 Installation of automatic samplers at designated transport sites.

0800 Start of NaBr injection and automatic samplers downstream from PC6,625. 

Collection of background bromide samples between PCO and PC5,280.

0830 Estimation of traveltimes between PCO and PC5,280.

1000 Collection and processing of water-quality samples collected at inflow sites.

0730 Collection and processing of synoptic water-quality samples from PCI 1,483 to PC6,625.

Collection of bromide samples by hand in response to difficulties with automatic samplers. 

Start of instantaneous streamflow measurements along reach.

1100 End of synoptic water-quality sampling and NaBr injection. 

Relocation of injection equipment to upper injection site.

1200 Preparation of LiBr solution.

End of instantaneous streamflow measurements along reach.

1830 End of bromide sampling at furthest downstream transport site in reach (PCI 1,483).

0730 Collection and processing of synoptic water-quality samples and instantaneous streamflow

measurements from PC28,348 (USGS 09306222) to PC20.708 (team I). 

Collection and processing of synoptic water-quality samples and instantaneous streamflow 

measurements from PC 17,860 to PC 14,789 (team 2).

0800 Start of LiBr injection downstream from PCO.

Collection of bromide samples by hand in response to difficulties with automatic samplers.

1030 End of water-quality sampling along secondary study reach by all teams. 

1800 Initialization of automatic samplers for limited sample collection during night.

0730 Collection and processing of synoptic water-quality samples from PC5,280 to PCO.

Collection of bromide samples by hand in response to difficulties with automatic samplers 

Start of instantaneous streamflow measurements along reach.

1100 End of synoptic water-quality sampling and LiBr injection.

1200 End of instantaneous streamflow measurements along reach.

1630 End of bromide sampling at furthest downstream transport site in reach (PC5,280).

reasons. The lower two-thirds of the study area 

(secondary study reach) was investigated by using 

conventional current-meter techniques and synoptic 

water-quality sampling. Several instantaneous streamflow measurements were made at selected sites as a 

quality-control measure. These data provided a 

measure of the stability of the streamflow over the 

several days of field activities and during the actual 

synoptic sampling. These data also provided a

measure of the reasonableness of the streamflow 

estimates using tracer-dilution techniques. Synoptic 

sampling along the primary and secondary reaches 

was done on three separate days. In each case, 

synoptic sampling was scheduled to be done as early 

in the day as possible to avoid potential input from 

melting ice along the banks of Piceance Creek. 

Sampling was done in an upstream order to avoid 

potential contamination.

8 Baseline Characterization of Water Quality and Mass Loading in Piceance Creek, Rio Blanco County, Colorado, December 2000
Tracer Injection

A reconnaissance of the study area in September 

2000 indicated that two tracer injections were needed 

along the primary study reach because of the length of 

the reach, the low streamflow velocity, and the presence of a small irrigation impoundment between 

PC5,280 and PC6,625. Bromide was chosen as the 

tracer because of the low concentrations in samples 

collected during the reconnaissance (James W. Ball, 

USGS, written commun., 2000). The median bromide 

concentration was 0.09 milligram per liter in 25 background samples collected. The first injection began at 

0800 on December 4, 2000, at PC6,625 and was 

continuous for 28 hours (table 2). A concentrated solution of sodium bromide (NaBr) was injected using a 

positive-displacement metering pump system. The 

stream reach extended from just downstream from 

PC6,625 to PCI 1,483 (fig. 2). Four samples of the 

injectate were collected periodically to confirm 

steady-state injection parameters. The samples were 

subsequently analyzed by the USGS National 

Research Program in Boulder, Colorado, to determine 

injection rates and bromide concentrations (James W. 

Ball, USGS, written commun., 2001). The injection 

rate varied by less than 3 percent and ranged from 325 

to 335 milliliters per minute (fig. 4); the average rate 

of 332 milliliters per minute was used to calculate 

streamflow. The bromide concentration ranged from 

176.4 to 177.2 grams per liter (fig. 4); the average 

concentration of 176.7 grams per liter was used to 

calculate streamflow.

The second injection began at 0800 on 

December 6, 2000, and continued for 27 hours 

(table 2). A concentrated solution of lithium bromide 

(LiBr) was injected along the stream reach from just 

downstream from the Ryan Gulch streamflow-gaging 

station (PCO).to PC5,280 (fig. 2). Seven injectate 

samples were collected and subsequently analyzed to 

determine injection rates and bromide concentrations 

(James W. Ball, USGS, written commun., 2001). The 

variability in the bromide concentrations for this injection was larger than expected. Concentrations in three 

samples collected the day before the synoptic 

sampling were statistically different from the four 

collected the day of sampling (James W. Ball, USGS, 

written commun., 2001). As such, only the samples 

collected on the day of the synoptic sampling were 

used to calculate streamflow. The injection rate for 

these four samples varied by 1 percent and ranged

from 318.6 to 321.2 milliliters per minute (fig. 4); the 

average rate of 320 milliliters per minute was used to 

calculate streamflow. The bromide concentration 

ranged from 165.1 to 173.5 grams per liter (fig. 4); the 

average concentration of 168.9 grams per liter was 

used to calculate streamflow.

Multiple bromide samples were collected at 

eight transport sites (table 1 and fig. 2) in Piceance 

Creek during the two tracer injections. Transport sites 

are sampling locations where numerous tracer samples 

are collected to determine if steady-state injection 

parameters have been established prior to synoptic 

sampling. Transport sites T5 to T8 were associated 

with the NaBr injection from PC6,625 to PCI 1,483 on 

December 4 and 5, 2000 (fig. 5). Transport sites Tl to 

T4 were associated with the LiBr injection from PCO 

to PC5,280 on December 6 and 7, 2000 (fig. 6). Data 

collected at the transport sites are. used to determine if 

tracer concentrations in the stream have reached a 

plateau concentration, which indicates that stable 

injection parameters have been attained. Also, the 

decrease in plateau concentrations at subsequent 

downstream transport sites can be used as a measure of 

the increase in streamflow at these locations (Kimball, 

1997). Tracer samples collected at these sites generally 

are collected manually as the tracer arrives at each site. 

Thereafter, it is common to use automatic samplers 

programmed to collect samples at pre-determined 

times and/or intervals; automatic samplers provide the 

temporal coverage that cannot be easily maintained by 

manual sampling.

The automatic samplers were only marginally 

successful during the NaBr injection on December 4 

and 5 because of cold temperatures in the study area. 

Intake lines became restricted with ice or froze entirely 

as water was pumped from the creek. Manual 

sampling procedures were implemented at 0730 on 

December 5 when it became apparent that the 

samplers had not functioned as anticipated (table 2). 

No plateau concentrations were calculated at T5, T6, 

T7, and T8 because of the limited number of samples 

and the concern that the samples might not accurately 

represent the bromide concentration in the creek 

(fig 5). It was assumed, however, that steady-state 

injection conditions were in effect and that the injection had proceeded long enough to reach plateau 

concentrations. Time of travel estimates using a fluorescent dye injection the previous day indicated that 

sufficient time had elapsed for the bromide tracer to 

come to a plateau in Piceance Creek. Therefore,

METHODS OF DATA COLLECTION
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DECEMBER 2000

Figure 4. Injection rates and bromide concentrations from injectate samples collected during 

tracer-injection study in Piceance Creek, December 4 and 5, 2000, and December 7, 2000.

bromide samples collected manually at about the same 

time as the synoptic water-quality sample were used to 

represent plateau bromide concentrations at T5, T6, 

TV, andT8.

The majority of LiBr samples collected 

December 6 and 7 were collected manually because of 

the limitations encountered earlier with the automatic 

samplers. However, the intake tubing to the automatic 

samplers was modified so at least one or two samples 

could be collected early on December 7. These data 

points were important in determining if tracer concentrations in the stream had reached plateau concentrations. Sufficient data were collected to calculate 

plateau concentrations at Tl, T2, T3, and T4 (fig. 6). 

The synoptic-bromide concentrations at Tl, T3, and 

T4 compare favorably with the calculated bromide 

plateaus at each site, whereas, the synoptic concentration at T2 was somewhat higher than the plateau 

concentration. It appears that a change in pump parameters increased the bromide concentration in the steam. 

A more complete description of this event is forthcoming. Samples collected at the rise and fall of the

bromide injection were not used to calculate plateau 

concentrations.

Supplemental Instantaneous Streamflow 

Measurements

Instantaneous Streamflow measurements using 

standard techniques (Rantz and others, 1982) were 

made at selected sites along the primary and secondary 

study reaches. These data were used to determine if 

Streamflow conditions remained constant throughout 

the study period, particularly during synoptic 

sampling. In addition, the measurements help determine the reasonableness of the tracer-dilution streamflow estimates. The data, however, were not intended 

as a check of the accuracy of the tracer-dilution 

Streamflow estimates because standard techniques do 

not measure the flow in the hyporheic zone (Zellweger 

and others, 1988). In high-gradient mountain streams 

with rock and cobble streambeds, tracer-dilution techniques have been reported to account for about 

30 percent more water than instantaneous Streamflow 

measurements (Kimball and others, 1998). Overall,

10 Baseline Characterization of Water Quality and Mass Loading in Piceance Creek, Rio Blanco County, Colorado, December 2000
T5(PC6,813)

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DECEMBER 2000

EXPLANATION

O TRANSPORT SAMPLE O TRANSPORT SAMPLE (SUSPECT) ^ SYNOPTIC SAMPLE A INJECTION START

Note: Vertical reference line represents the approximate time when increased streamflow affected injectate-bromide concentrations. 

Traveltimes estimated from earlier dye injection efforts.

Figure 5. Bromide concentrations at transport sites T5 to T8 in Piceance Creek, December 4 and 5, 2000.

METHODS OF DATA COLLECTION 11
T1 (PC180)

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0600 0800 -1000 1200 1400 1600 1800 2000 2200 2400 0200 0400 0600 0800 1000 1200 1400 1600 1800 2000

6 | 7

DECEMBER 2000

EXPLANATION

---- PLATEAU O TRANSPORT SAMPLE -*- SYNOPTIC SAMPLE A INJECTION START

Figure 6. Bromide concentrations at transport sites T1 to T4 in Piceance Creek, December 6 and 7, 2000.

12 Baseline Characterization of Water Quality and Mass Loading in Piceance Creek, Rio Blanco County, Colorado, December 2000
the error associated with the instantaneous streamflow 

measurements made during this study was estimated to 

be about 15 percent.

Streamflow measurements made at PCO 

(December 4 at 0740 and December 7 at 0800) and 

PCI 1,483 (December 3 at 0945 and December 5 at 

1000) were used to determine if base-flow conditions 

remained constant during the study period (table 3). 

Instantaneous measurements were needed because the 

two streamflow-gaging stations in the study area were 

not operational at the time because of freezing temperatures. The relative percent difference (RPD) of the 

two sets of measurements was about 6 percent at PCO 

and 9 percent at PCI 1,483. RPD is calculated by 

dividing the absolute value of the streamflow difference by the mean of the streamflow; the result is 

shown as a percentage. These data indicated that baseline streamflow conditions were relatively stable 

during the study period.

Streamflow measurements also were done to 

determine if streamflow conditions remained constant 

during synoptic water-quality sampling on 

December 5 and December 7, 2000. Measurements 

made on December 5 at PC6,625 (at 0900) and 

PC 11,483 (at 1000) indicated that streamflow probably was stable at 0900 hours (table 3); synoptic 

sampling had proceeded in an upstream order to 

PC8,448 by this time (table 1). However, less than 

2 hours later, streamflow at PC6,625 had increased 

nearly twofold (960 liters/second; table 3) as water 

was released from the upstream impoundment. It 

appears that an ice dam across the outlet works of the 

impoundment gave way releasing a large amount of 

water. Analysis of specific conductance and pH data 

indicated that the water was native to the stream 

(table 1) and, as such, no change in chemical concentrations was expected. All synoptic samples collected 

downstream to PC7,978 exhibited lower than expected 

bromide concentrations, which indicated that dilution 

of the injectate solution had occurred. The implications of the change in streamflow on the synoptic 

bromide concentrations and subsequent estimates of 

streamflow downstream will be discussed in a later 

section. On December 7, instantaneous measurements 

at PCO; PC2,205; and PCS,280 and gage-height 

measurements at PCO indicated that streamflow was 

relatively stable throughout the synoptic sampling on 

that date (table 3).

Synoptic Sampling

Synoptic sampling provides a spatially detailed 

description of the water quality in a stream and is 

accomplished by sampling numerous sites in a relatively short time. In addition, synoptic samples 

provide both the tracer-concentration data needed to 

estimate streamflow and the concentration data needed 

to compute loads. Synoptic sampling along each 

subreach of Piceance Creek was conducted early in the 

morning and as quickly as possible to avoid changes in 

streamflow due to diurnal variation. Samples were 

collected in an upstream order near the centroid of the 

stream in clean, 4-liter plastic containers. The samples 

were transported to a centrally located staging area 

and processed as soon as possible. A list of the sites, 

sampling dates, and sampling times are in table 1. 

Field values of pH and specific conductance were 

determined on an unfiltered aliquot of each sample 

(table 1). The remaining sample volume was filtered 

through a 0.45-millimeter capsule filter and preserved 

as described by Horowitz and others (1994). All 

synoptic samples were submitted for analysis to the 

USGS National Water Quality Laboratory (NWQL) in 

Lakewood, Colorado.

All synoptic water-quality samples were 

analyzed for a base list of constituents that was consistent with the standard list of analytes in the groundwater monitoring program for the Yankee Gulch 

Project (Agapito Associates, Inc., 1999). The analytes 

included dissolved major ions, selected trace constituents, alkalinity, and residue on evaporation. These 

constituents are possible indicators of fluid migration 

away from the production solution-mining zone 

(Douglas B. Yager, U.S. Geological Survey, written 

commun., 2000). In addition, samples collected at 

seven spatially dispersed sites (designated as indicator 

sites in table 1) were analyzed for additional dissolved 

constituents consistent with the USGS water-quality 

monitoring program at the Ryan Gulch (09306200) 

and White River (09306222) streamflow-gaging 

stations (Crowfoot and others, 2001) and the comprehensive list of parameters for the ground-water monitoring program at the Yankee Gulch site (Agapito 

Associates, Inc., 1999). This expanded list included 

additional trace constituents, dissolved organic carbon, 

nitrogen and phosphorus compounds, and gross alpha 

and beta radioactivity. Specific chemical data for all 

sites are listed in table 5 in the Data Section at the back 

of the report.

METHODS OF DATA COLLECTION 13
Table 3. Summary of instantaneous streamflow measurements made along the primary study reach of Piceance Creek, 

December 3-7, 2000

[L/s, liters per second; , no data; 09306200 denotes U.S. Geological Survey streamflow-gaging-station number]

Outside

Site name Date Time St^mf' ow1 B?9* (Us) height2

(feet)

Remarks

PC 11, 483

PCO

PC6,625

PC 11, 483

PC6,625

PC8,098

PC 11, 483

PCO

PC5,280

PCO

PCO

PC2,205

PCO

PC5,280

PCO

PCO

PC6.625

12-3-00

12-4-00

12-5-00

12-5-00

12-5-00

12-5-00

12-5-00

12-7-00

12-7-00

12-7-00

12-7-00

12-7-00

12-7-00

12-7-00

12-7-00

12-7-00

12-7-00

0945

0740

0900

1000

1040

1120

1200

0700

0720

0800

0840

0850

0915

0930

1010

1100

1130

509

448

500

466

960

' 952

764

--

451

421

--

434

--

438

--

730

Prior to injection. Needed to determine injection parameters.

Prior to injection along reach.

Above injection site. Sampling started at 0730 at PCI 1,483.

Downstream end of subreach. Soft bottom with ice throughout. Slow 

velocities. Measurement likely underestimated streamflow.

Rise in stage noted. Abrupt change in streamflow due to release of water 

from impoundment. Last synoptic sample collected at 1040 at PC6,625.

Streamflow increased in response to release of water from impoundment.

Streamflow increasing in response to release of water from impoundment.

3.58 At 09306200 (Ryan Gulch streamflow-gaging station). Outside gage height 

only. Sampling started at 0700 at PC5,280.

At downstream end of subreach.

3.58 At 09306200. Approximately 20 percent shore ice.

3.58 At 09306200. Outside gage height only.

At Horse Draw bridge to mine site.

3.62 At 09306200. Outside gage height only.

At downstream end of subreach.

3.61 At 09306200. Outside gage height only.

3.58 At 09306200. Outside gage height only. Last synoptic sample collected 

at 1040 at 09306200.

Measurement made after last synoptic sampling along upper reach.

Measurements were rated as fair to poor with an estimated error of 15 percent. 

Reading taken from wire weight with an estimated error of plus or minus 0.02 foot.

Quality Assurance

Data-collection and analytical procedures used 

in this study incorporated practices designed to 

control, verify, and assess the quality of the sample 

data. Methods and associated quality control for 

collection and field processing of water-quality 

samples are described by Ward and Harr (1990), 

Horowitz and others (1994), and Wilde and others 

(1998). The quality of analytical results for waterquality samples can be evaluated with data from 

quality-control samples submitted from the field and 

analyzed concurrently in the laboratory with routine 

samples. In addition, internal quality-assurance 

practices at the NWQL were performed systematically

to provide quality control of the analytical procedures 

(Pritt and Raese, 1995).

Four duplicate samples were collected to 

provide quantitative information on the precision and 

bias of the overall field and laboratory process. 

Selected analytical results for the field duplicates are 

presented in table 6 in the Data Section at the back of 

the report. The RPD among the duplicate concentrations generally was less than 10 percent, which indicates acceptable precision for analytical results.

Two field blanks were analyzed to identify the 

presence and magnitude of contamination that potentially could bias analytical results. Certified 

deionized water was used to produce a field blank that 

was subjected to the same processing and analysis as

14 Baseline Characterization of Water Quality and Mass Loading in Piceance Creek, Rio Blanco County, Colorado, December 2000
an environmental sample. Analytical results for field 

blanks are presented in table 7 in the Data Section at 

the back of the report. For the most part, the concentrations in the blanks were at or below the method 

reporting limits, which indicates that the synoptic 

samples were free of significant or systematic bias 

from contamination. However, dissolved aluminum 

and zinc concentrations in the blank collected on 

December 7, 2000, were five to six times higher than 

the method reporting level. Further analysis determined that a systematic aluminum contamination had 

occurred in all synoptic samples collected that day. It 

is unclear if the contamination was associated the with 

field-processing procedures or the laboratory analysis. 

Nevertheless, the contamination was substantial 

enough to require removal of all aluminum data for 

samples collected on December 7, 2000. This was not 

the case with the elevated zinc concentration in the 

same blank sample. The contamination was not shown 

to be systematic in any other water-quality sample, and 

the data were retained.

BASELINE CHARACTERIZATION OF 

WATER QUALITY

Routine water-quality data have been collected 

at the Ryan Gulch (09306200; PCO) and White River 

(09306222; PC28,348) streamflow-gaging stations 

since 1970 (Crowfoot and others, 2001). Physical and 

chemical data collected from 1977 to 1981 for streams 

in the Piceance Creek Basin have been summarized 

(Tobin and others, 1985). A spatially comprehensive 

data-collection effort in Piceance Creek during steadyflow conditions in March 1981 indicated that major 

dissolved constituents in Piceance Creek generally 

increased in the downstream direction as ground water 

discharged to springs, streams, and valley-fill alluvial 

aquifers in various reaches of Piceance Creek (Tobin, 

1987). The exact location and extent of hydrologic 

connections between aquifers and streams are not well 

known although bedrock and fracture-controlled 

springs are observed along Piceance Creek. A substantial change in water quality was observed as ground 

water discharged upward through an extensive northwest-southeast fracture zone that crosses Piceance 

Creek in the area known as Alkali Flat (Tobin, 1987) 

(fig. 2). Salts precipitated on the land surface by 

evaporation of the shallow ground water are visible 

during base-flow conditions. Data collected as part of

this study provide (1) an updated characterization of 

the water quality in Piceance Creek between the two 

USGS streamflow-gaging stations and (2) a baseline 

characterization of the water quality in Piceance Creek 

before full-scale nahcolite solution mining begins at 

the Yankee Gulch Project.

Physical Properties

In December 2000, pH values in Piceance Creek 

were stable throughout the study reach (fig. 7). The pH 

values ranged from 7.9 to 8.1 (table 1) with a median 

value of 8.0 standard units. Specific conductance 

increased steadily along the upper two-thirds of the 

study reach to PCI 7,860 at a rate of about 

10 microsiemens per centimeter per kilometer (fig. 7). 

Along the reach that included the Alkali Flat area 

(PC20J08 to PC23J21), the rate increased to nearly 

1,000 microsiemens per centimeter per kilometer, 

which equated to a 14-percent increase in less than 

3,000 meters. Specific conductance at a spring contact 

in the area (site AFS) was measured at 

12,700 microsiemens per centimeter (table 1). Specific 

conductance remained elevated downstream to 

PC28,348. Overall, specific conductance in Piceance 

Creek ranged from 1,540 to 1,980 microsiemens per 

centimeter. The profile for dissolved-solids concentrations was similar to that described for specific conductance (fig. 7). Specific conductance was shown to be a 

good predictor of dissolved solids in Piceance Creek 

including the stream reach downstream from Alkali 

Flat (table 4).

Major-Ion Concentrations

Tobin (1987) reported the principal dissolved 

constituents in water from Piceance Creek as bicarbonate, sulfate, and sodium. In December 2000, the 

principal dissolved constituents in the study area 

remained the same. The median bicarbonate concentration was 610 milligrams per liter (table 5). The 

median sulfate concentration was 420 milligrams per 

liter. The median sodium concentration was 

170 milligrams per liter. Ground-water dissolution of 

evaporite minerals of nahcolite and halite (Green River 

Formation), and oxidation of pyrite and hydrogensulfide gas (Uinta Formation) are most likely sources

BASELINE CHARACTERIZATION OF WATER QUALITY 15
DECEMBER 7 DECEMBERS DECEMBER 6

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DISTANCE DOWNSTREAM FROM USGS STREAMFLOW-GAGING 

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Figure 7. Values of pH, specific conductance, and dissolved solids in Piceance Creek, December 5-7, 2000.

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of these ions (George J. Saulnier, Jr., Duke Engineering, written commun., 2001).

Table 4. Linear regression statistics for predicting 

dissolved solids and selected ion concentrations in 

Piceance Creek from specific-conductance data, 

December 2000

Constituent 

(in milligram per liter)

Dissolved solids

Sodium

Bicarbonate

Chloride

Slope

0.633

.298

.693

.047

y intercept

31.4

-319.0

-530.8

-60.2

R2

0.91

.96

.85

.85

Sodium, bicarbonate, and chloride concentrations increased gradually downstream from PCO to 

PC20J08 as ground water discharged to the stream 

valley (table 5 and figs. 8 and 9). Overall, the increase 

along this 21-kilometer reach was from 25 to 35 

percent; no sodium data were available from PC6,813 

to PC 11,483 because sodium bromide was used as the

tracer along this reach. In contrast, a sharp increase in 

sodium (35 percent), bicarbonate (19 percent), and 

chloride (89 percent) concentrations was measured 

along a 3-kilometer reach between PC20,708 and 

PC23,721. This short reach of Piceance Creek flows 

across the area known as Alkali Flat (PC20,708 to 

PC23,721). Sulfate, calcium, magnesium, potassium, 

silica, and fluoride concentrations remained relatively 

constant throughout the study area including Alkali 

Flat. The relation of specific conductance to bicarbonate, sodium, and chloride concentrations in 

Piceance Creek is listed in table 4.

Trace-Constituent Concentrations

Characteristic trace constituents in the two 

major bedrock aquifers of the Piceance Creek Basin 

were identified as strontium in the Uinta Formation 

and barium, boron, and lithium in the Green River 

Formation (Tobin, 1987). Concentrations of barium, 

boron, lithium, and strontium also were elevated in

16 Baseline Characterization of Water Quality and Mass Loading in Piceance Creek, Rio Blanco County, Colorado, December 2000
DECEMBER? DECEMBERS DECEMBERS

DC

LU

C/)

DC

LU 300

250

DC

^ 200

- 150

1 I | 

I

i

A SODIUM, DISSOLVED

A CALCIUM, DISSOLVED

O MAGNESIUM, DISSOLVED

* POTASSIUM, DISSOLVED

a

5,000 10,000 15,000 20,000 25,000 30,000

DISTANCE DOWNSTREAM FROM USGS STREAMFLOW-GAGING 

STATION 09306200, IN METERS

Figure 8. Selected dissolved-cation concentrations in Piceance Creek, December 5-7, 2000.

surface-water samples collected in Piceance Creek 

in December 2000 (table 5 and fig. 10). Strontium 

concentrations ranged from 2,810 to 3,390 micrograms per liter and were the highest of the trace 

constituents. However, concentrations remained relatively stable (median value about 2,990 micrograms 

per liter) throughout Piceance Creek including the 

reach along Alkali Flat. Barium concentrations 

(median value 75 micrograms per liter) and boron 

concentrations (median value 180 micrograms per 

liter) increased by about 50 to 65 percent from 

upstream to downstream. The largest increase in 

barium and boron concentrations occurred in the area 

of Alkali Flat. Although lithium was not analyzed for 

at all sites, a 70-percent increase in concentration was 

measured between PC 17,860 and PC23.721. This 

reach includes the Alkali Flat area. Most other traceconstituent concentrations were at or near method 

reporting limits and little or no downstream increases 

were measured (table 5 and fig. 10).

TRACER-INJECTION RESULTS

Tracer-injection methods are used to determine 

streamflow at numerous sites in a relatively short time. 

This determination is accomplished by continuously 

injecting a known mass of a conservative tracer into 

the stream and measuring the concentration of the 

tracer at each downstream location. Using the principle of conservation of mass, a decrease in tracer 

concentration downstream (dilution) is a measure of 

an increase in streamflow. Variations in streamflow, 

injection flux (mass per unit time), and analytical 

precision can affect the measured tracer concentration 

at each site. An understanding of these variables is 

needed when interpreting the bromide profiles 

generated as part of these tracer injections. This 

understanding is particularly important in a stream 

such as Piceance Creek where downstream increases 

in streamflow were relatively small.

TRACER-INJECTION RESULTS 17
DECEMBER? DECEMBERS DECEMBERS

DC 

LLJ

CC 

LJJ 

CL

CO

DC 

O

O

DCILU 

O

Z 

O 

O

5,000 10,000 15,000 20,000 25,000

DISTANCE DOWNSTREAM FROM USGS STREAMFLOWGAGING STATION 09306200, IN METERS

Figure 9. Selected dissolved-anion concentrations in Piceance Creek, December 5-7, 2000.

800

600

t

(

200

0 

50

40

30

20

i 

i

10

n<

A BICARBONATE

A ALKALINITY

- O SULFATE, DISSOLVED

iAA AAA A

A A A

jj^^(5W^^p

i i i i i

A A AA A A

AtvA^A A AA

A

A

i i i 1 i

, | , , , |

A CHLORIDE, DISSOLVED

A SILICA, DISSOLVED

_ O FLUORIDE, DISS

-

-

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-

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OLVED

A A A A

SSBOOOXBCOOOXDO, O

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A

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A

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A

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I I 1 1 1 I I 1 1 1 1 1 1 I 1 1 I

A

A A -

A A 

A A

AAA A A A A

-

, , O D , Q , i O, , , O, Q , , ,O ,

30,000

18 Baseline Characterization of Water Quality and Mass Loading in Piceance Creek, Rio Blanco County, Colorado, December 2000
DECEMBER/ DECEMBER 5 DECEMBERS

DC 

LU

H

_i

DC 

UU 

Q_

CO

DC 

O 

O 

DC 

O

H.U

3.5

3.0

2.5

2.0

L

1.5

1.0

0.5

n

i |

; A ARSENIC, DISSOLVED

~ A ALUMINUM, DISSOLVED

; O ANTIMONY, DISSOLVED

-

_

"

A

- A

A

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~ AA A AA A

/v\ A A

/v\ /y\ A^

AW AAA

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A A

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AA A A

A

A

A A A

A AA

AA A AA A

tSjMSKfcrffih0, 0

, , | , , , i | i . i i | i

Method reporting limit for aluminum was 1 .0 (ig/L

Method reporting limit for antimony was 0.05 |ig/L

-

-

A

A 1

A -

A A -

A ;

A

A

A

A A A

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, , °, n , 9 , , n. . . o. n . . o _ :

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O 300

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DC

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O

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O

250

200

150

100

50

1 1 1 1 1 1 1 1 1 1 1

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7 A BORON, DISSOLVED 

- O IRON, DISSOLVED

7 A

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-

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f* A -

i i | i i i i | i i i i | i i i i

All iron values reported as less than method reporting limit with the j 

exception of one estimated value of 6.8 ng/L. Two method reporting 

limits were reported: 10 and 30 |ig/L. '.

A J

A A :

A A A A ~

_

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CC

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1 1 1 1 | ! 1 1 | 1

\ A LITHIUM, DISSOLVED

A STRONTIUM, DISSOLVED

- O ZINC, DISSOLVED

A

.

-

3~

^(SJX^BJ^gj^D

^

A^»*AAAAAAAAA

A A

1 ' ' ' ' ' ' ' ' ' '

Lithium data for PCO and PC28.348 were collected as part of

routine USGS water-quality sampling on November 15, 2000

(Crowfoot and others, 2002)

-

.

.

AA * A AA A~

A

-

-

A ~

-

-

-

-

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n

0 5,000 10,000 15,000 20,000 25,000 30,000

DISTANCE DOWNSTREAM FROM USGS STREAMFLOWGAGING STATION 09306200, IN METERS

Figure 10. Selected dissolved-trace-constituent concentrations in Piceance Creek, December 5-7, 2000.

TRACER-INJECTION RESULTS 19
Synoptic Bromide Concentrations

The first synoptic sampling event began at 0730 

on December 5, 2000, along the primary study reach 

from PC6,625 to PCI 1,483 (fig. 2). Injectate-bromide 

concentrations in Piceance Creek were assumed to be 

at plateau concentrations because nearly 24 hours had 

elapsed since the start of the NaBr injection. Sampling 

began at the downstream site and proceeded upstream 

under stable streamflow conditions. However, a rapid 

increase in streamflow part way through the sampling 

diluted the synoptic-bromide concentrations in the 

stream upstream from PC8,098 (fig. 5); samples 

collected downstream from PC8,098 were unaffected 

by the increase because the samples had already been 

collected. As a result, synoptic bromide concentrations 

upstream from PC8,098 did not represent steady-state 

streamflow conditions (fig. 11). For the purpose of 

defining a bromide profile along the affected reach, the 

last bromide concentration collected at PC6,813 as 

part of the transport data (at 0815 hours) was substituted for the suspect synoptic concentration at this site 

(fig. 5). Intermediate bromide concentrations were 

estimated using a linear interpolation between 

PC6,813 and PC8,098. Bromide concentrations generally decreased downstream from PCS,098 along the 

reach unaffected by the sudden increase in streamflow. 

A smoothed line was drawn for these remaining 

bromide concentrations. The bromide concentrations 

from the smoothed line were used to develop an estimated streamflow profile for this reach. An error of 

plus or minus 3 percent was assumed for all bromide 

determinations.

The second synoptic sampling began at 0730 on 

December 7, 2000, along the upper section of the 

primary study reach from PCO to PC5,280 (fig. 2). 

Synoptic sampling was done in an upstream order 

nearly 24 hours after the start of the LiBr injection. 

Supplemental streamflow measurements and stage 

data indicated that the streamflow was stable during 

the sampling (table 3). Synoptic bromide concentrations at PC180 (Tl), PC4,180 (T3), and PC5,280 (T4) 

compared well with plateau bromide concentrations 

(fig. 6), which indicates that the synoptic concentrations were representative of stable injection conditions. However, the synoptic bromide concentration at 

PC2,205 (T2) was higher than the plateau concentration at this transport site (fig. 6). Analysis of injectate 

bromide samples collected at 0655 (882 milligrams 

per second) and 0920 (922 milligrams per second)

indicated that a 4.5-percent increase in bromide flux to 

the stream occurred during this 2.5-hour period. 

Traveltimes from the injection site to PC2,205 (T2) 

support the hypothesis that elevated synoptic bromide 

concentrations observed between PC660 and PC4,180 

were the result of increased bromide flux to the 

stream. For the purpose of defining a bromide profile 

for this reach, the plateau bromide concentration at 

PC2,205 (T2) was used in place of the synoptic 

bromide concentration. A linear interpolation then was 

used between PC2,205 and PC660 and between 

PC2,205 and PC4,180 to define intermediate concentrations (fig. 12). Synoptic-bromide concentrations 

generally decreased downstream from PC4,180.

A smoothed line was drawn between PC4,180 

and PCS,280 (fig. 12).The bromide concentrations 

from the smoothed line were used to develop an estimated streamflow profile for the entire reach. An error 

of plus or minus 3 percent was assumed for all 

bromide determinations.

Estimation of Streamflow

Streamflow can be calculated at any site downstream from the tracer-injection site by using the 

concentration of the tracer in the stream, the background tracer concentration, the concentration of the 

injection solution, and the rate of injection. Streamflow profiles for each of the subreaches along the 

primary study reach of Piceance Creek (figs. 11 and 

12) were developed by using the following equation 

(modified from Ortiz and Bencala, 2001):

Q = QiNjC,NJ /(c-cp ) (i)

where

Q is streamflow, in liters per second; 

QjNJ is the rate of the tracer injection into the

stream, in liters per second; 

CINj is the tracer concentration in the injection

solution, in milligrams per liter; 

C is the tracer concentration from the smoothed 

tracer profile, in milligrams per 

liter; and 

CP is the tracer concentration in the background

sample, in milligrams per liter. 

The instream tracer concentration was determined at each synoptic sampling site from a smoothed

20 Baseline Characterization of Water Quality and Mass Loading in Piceance Creek, Rio Blanco County, Colorado, December 2000
3.5

3.0

iio<

QDC 1.5

O

CE 

CD

~ 1.0 

0.5

0

1,200

O

Z 1,000

O

O

LU

£ 800 

Q_

CE 

LU

^ 600

Z

O

LU 

CE

co

400

200

0

A

A

ESTIMATED BROMIDE CONCENTRATION

SYNOPTIC BROMIDE CONCENTRATION 

(DECEMBER 5, 2000)

BACKGROUND BROMIDE CONCENTRATION 

(DECEMBER 3, 2000)

Synoptic bromide concentrations upstream from 

PCS,098 appeared to be affected by release of 

water from upstream irrigation impoundment. 

Transport concentration at T5 used to define 

estimated bromide concentration curve.

 0- ESTIMATED STREAMFLOW 

D INSTANTANEOUS STREAMFLOW MEASUREMENT

6,000 6,500 7,000 7,500 8,000 8,500 9,000 9,500 10,000 10,500 11,000 11,500 12,000

DISTANCE DOWNSTREAM FROM USGS STREAMFLOWGAGING STATION 09306200, IN METERS

Figure 11. Bromide concentrations and estimated streamflow at synoptic sampling sites in Piceance Creek, 

December 5, 2000.

TRACER-INJECTION RESULTS 21
zee

O LU

Pb

S§ 

§1°s

LU ^

O 

DC 

CO

3.5

3.0

 - 2 ' 5

2.0

1.0

0.5

A

A

 ESTIMATED BROMIDE CONCENTRATION

A SYNOPTIC BROMIDE CONCENTRATION

(DECEMBER 7, 2000) 

A BACKGROUND BROMIDE CONCENTRATION

(DECEMBER 4, 2000)

* PLATEAU CONCENTRATION AT TRANSPORT SITE

. A, .A

2 

LL

LU 

DC

CO

1,200

1,000

800

Q

Z

o 

o

LU 

CO

DC 

LU 

Q_

CO 

DC 

LU

600

400

200

[]

-0- ESTIMATED STREAMFLOW 

D INSTANTANEOUS STREAMFLOW MEASUREMENT

o o o en n

500 1,000 1,500 2,000 2,500 3,000 3,500 4,000 4,500

DISTANCE DOWNSTREAM FROM USGS STREAMFLOWGAGING STATION 09306200, IN METERS

5,000 5,500

Figure 12: Bromide concentrations and estimated streamflow at synoptic sampling sites in Piceance Creek, 

December 7, 2000.

22 Baseline Characterization of Water Quality and Mass Loading in Piceance Creek, Rio Blanco County, Colorado, December 2000
profile of bromide concentrations (figs. 11 and 12). 

The median background bromide concentration was 

0.09 milligram per liter in 25 stream samples collected 

prior to the injection. The average bromide concentration in the NaBr injection solution was 

176,700 milligrams per liter; the average injection rate 

was 0.00553 liter per second. The average bromide 

concentration in the LiBr injection solution was 

168,900 milligrams per liter; the average injection rate 

was 0.00533 liter per second. Analytical uncertainty 

associated with these determinations was estimated at 

plus or minus 2 percent for the NaBr injection and 

4 percent for the LiBr injection (James W. Ball, U.S. 

Geological Survey, written commun., 2000).

The profiles show the increase in estimated 

streamflow along specific reaches of Piceance Creek. 

Streamflow increased by 14 percent or about 16 liters 

per second per 1,000 meters along the reach from PCO 

to PC5,280 (fig. 12). A similar increase (12 liters per 

second per 1,000 meters) was measured between

PC6,625 and PC9,938 (fig. 11). Even though the same 

general streamflow pattern appears to exist along the 

entire reach from PCO to PC9,939, the streamflow data 

derived from the two tracer injections should not be 

compared directly. Differences in sampling dates, 

injections solutions, injection parameters, and anomalies specific to each stream reach do not warrant the 

direct comparison of the streamflow estimates 

between the two reaches. Streamflow increased by 

25 percent downstream from PC9,938 as the valley 

floor narrowed and, presumably, ground-water inputs 

increased (fig. 2).

In addition, seven instantaneous streamflow 

measurements were done in the secondary study reach 

in conjunction with synoptic sampling on December 6, 

2000 (fig. 13). Streamflow generally increased downstream to PC17,860 and PC20,708. A substantial 

decrease in streamflow occurred between PC20,708 

and PC23,721 along the Alkali Flat area; the area is 

known to be a region of extensive fracturing. Stream1,400

1,200

o 

o

LU 1,000 

CO

DC 

LU 

Q.

<£ 800 

111

 600

O

UJ 

DC

CO

400

200

O

PRIMARY STUDY REACH

| Error bar (15 percent)

A December 5, 2000

d December 6, 2000

O December 7, 2000

 SECONDARY STUDY REACH

5,000 10,000 15,000 20,000 25,000 30,000

DISTANCE DOWNSTREAM FROM USGS STREAMFLOW-GAGING 

STATION 09306200, IN METERS

Figure 13. Instantaneous streamflow measurements along the primary and secondary study reaches in Piceance 

Creek, December 5-7, 2000.

TRACER-INJECTION RESULTS 23
flow profiles presented by Tobin (1987) show a similar 

decrease in streamflow near this reach, but additional 

stream flow data are needed to better quantify these 

findings. These streamflow data were used to calculate 

loads along this lower reach of the study area. Instantaneous streamflow data along the secondary study 

reach should not be compared directly with streamflow estimates derived from the tracer injections 

(figs. 11 and 12) because tracer-dilution techniques 

can account for about 30 percent more water (Kimball 

and others, 1998).

MASS LOADS

Downstream load profiles can be used to illustrate graphically the spatial distribution of mass loads 

at many locations along a main stem and can be used 

to identify sources and sinks that affect the constituent 

load. The downstream mass load profiles for this study 

represent the instantaneous loads at each main-stem 

sampling site for each of the two tracer-injection 

reaches in the primary study reach and along the 

secondary study reach. The three stream reaches are 

presented separately because, as stated previously, 

streamflow profiles used to compute loads were not 

continuous between study reaches. No significant load 

input to Piceance Creek was detected along the 

primary study reach. Although substantial increases in 

constituent concentration were observed near Alkali 

Flat, apparent losses in streamflow along the 

secondary study reach resulted in relatively small 

increases in load downstream to the end of the study 

reach.

Major Ions

Load profiles for dissolved cations (fig. 14) and 

anions (fig. 15) from PCO to PCI 1,483 were similar to 

streamflow profiles in Piceance Creek for these same 

reaches (figs. 11 and 12). Overall, the loads increased 

gradually along the primary study reach, and the only 

substantial increase in load occurred between PC9,938 

and PC 10,748. Increased loading along this short 

reach was more closely related to increased streamflow than to any large increase in concentration.

Presumably, ground-water inputs to the stream 

increased as the alluvial cross section constricted in 

the narrow valley.

Along the secondary study reach, the large 

increases in ion concentration that were observed in 

December 2000 (figs. 8 and 9) were offset by 

decreased streamflow along much of the reach 

(fig. 13). The resulting load profiles for most dissolved 

cations and anions downstream from PC 11,483 

showed little or no increase (figs. 14 and 15). The only 

constituent load that increased appreciably along this 

reach was chloride, which increased nearly 50 percent. 

Additional investigation along the secondary study 

reach is needed to substantiate these findings.

Trace Constituents

Selected dissolved metal loading (fig. 16) from 

PCO to PCI 1,483 also was similar to streamflow 

profiles in Piceance Creek for these same reaches 

(figs. 11 and 12). Overall, the loads increased gradually along the primary study reach and the only 

substantial increase in load occurred between PC9,938 

and PC 10,748 where, presumably, ground-water 

inputs to the stream increased as the alluvial valley 

narrowed. Barium, boron, and strontium loads were 

the only trace constituents readily quantifiable in the 

study area and, as such, are the only ones shown in 

figure 16. Most of the other concentrations were 

reported as near or below the method reporting levels.

Along the secondary study reach, load profiles 

for dissolved-trace constituents downstream from 

PCI 1,483 showed little or no increase (fig. 16). 

Because strontium concentrations (fig. 10) were 

unchanged throughout the secondary study reach, the 

resulting load profile indicated a loss of strontium 

mass downstream to PC28,348. Strontium is generally 

associated with the ground water of the Uinta Formation so increased ground water from the Green River 

Formation could reduce the proportion of strontium in 

this area (George J. Saulnier, Jr., Duke Engineering, 

written commun., 2001). Additional investigation 

along the secondary reach is needed to substantiate 

these findings.

24 Baseline Characterization of Water Quality and Mass Loading in Piceance Creek, Rio Blanco County, Colorado, December 2000
i£U,UUU

15,000

10,000 

(

5,000-

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0 -- 

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.

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12,000 15,000 18,000 21,000 24,000 27,000 30,000

DISTANCE DOWNSTREAM FROM USGS STREAMFLOWGAGING STATION 09306200, IN METERS

EXPLANATION

DISSOLVED CALCIUM LOAD A DISSOLVED MAGNESIUM LOAD O DISSOLVED SODIUM LOAD

Figure 14. Dissolved calcium, magnesium, and sodium loads in Piceance Creek, December 5-7, 2000.

MASS LOADS 25
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DISTANCE DOWNSTREAM FROM USGS STREAMFLOWGAGING STATION 09306200, IN METERS

EXPLANATION

A DISSOLVED BICARBONATE LOAD A DISSOLVED SULFATE LOAD O DISSOLVED CHLORIDE LOAD

Figure 15. Dissolved bicarbonate, sulfate, and chloride loads in Piceance Creek, December 5-7, 2000.

26 Baseline Characterization of Water Quality and Mass Loading in Piceance Creek, Rio Blanco County, Colorado, December 2000
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5

n

12,000 15,000 18,000 21,000 24,000 27,000 30,000

>-

Q

DC

111 

0_

CO

^

DC 

CD

g

2

z

z" 

o

DC 

O

m

DISTANCE DOWNSTREAM FROM USGS STREAMFLOW-GAGING 

STATION 09306200, IN METERS

EXPLANATION

A DISSOLVED BARIUM LOAD A DISSOLVED BORON LOAD O DISSOLVED STRONTIUM LOAD

Figure 16. Dissolved barium, boron, and strontium loads in Piceance Creek, December 5-7, 2000.

MASS LOADS 27
SUMMARY

In recent years, the emphasis of resource development in the Piceance Basin has turned to commercial nahcolite solution mining for sodium bicarbonate 

(baking soda) and sodium carbonate (soda ash). The 

Yankee Gulch Sodium Minerals Project was required 

to submit a monitoring plan that, in part, would characterize the baseline water quality in the adjacent 

Piceance Creek. The U.S. Geological Survey (USGS) 

provided this characterization in cooperation with Rio 

Blanco County, Colorado. The purpose of this report is 

to provide a baseline characterization of the water 

quality in Piceance Creek and to quantify the mass 

load for selected chemical constituents in Piceance 

Creek during base-flow conditions. Physical and 

chemical data were collected during December 2000 

at 47 main-stem sites and 4 inflow sites. The study 

area extended about 28 kilometers along Piceance 

Creek between the USGS streamflow-gaging stations 

09306200 (PCO) and 09306222 (PC28,348). The 

primary study reach was along the approximately 

11.5 kilometers of the study area adjacent to the lease 

boundary for the Yankee Gulch Sodium Minerals 

Project.

Tracer-dilution techniques and instantaneous 

measurements were used to determine streamflow in 

Piceance Creek. Synoptic-sampling techniques were 

used to determine baseline concentrations for selected 

constituents in Piceance Creek. Synoptic water-quality 

samples were analyzed for a base list of constituents 

that was consistent with the ground-water monitoring 

program for the mine. The constituents are possible . 

indicators of fluid migration away from the solutionmining zone. Load profiles along subreaches of the 

creek were generated by combining tracer-dilution and 

synoptic-sampling techniques.

Data collected as part of this study provide an 

updated characterization of the water quality in 

Piceance Creek between the two USGS streamflowgaging stations 09306200 and 09306222. In March 

1981, a spatially comprehensive data-collection effort 

in Piceance Creek indicated increases in major 

dissolved constituents in the downstream direction as 

ground water discharged to springs, streams, and 

valley-fill alluvial aquifers. Additionally, a substantial 

change in water quality was observed as ground water 

discharged upward through an extensive northwestsoutheast trending fracture zone that crosses Piceance 

Creek in the area known as Alkali Flat.

In December 2000, pH values in Piceance Creek 

were stable throughout the study area and ranged from 

7.9 to 8.1 standard units. Specific conductance 

increased steadily along the upper two-thirds of the 

study reach. The rate increased by nearly 14 percent 

along the reach that included Alkali Flat (PC20,708 to 

PC23,721). Specific conductance was shown to be a 

good predictor of dissolved solids in Piceance Creek. 

In 1987, bicarbonate, sulfate, and sodium were 

reported as the principal dissolved constituents in 

Piceance Creek. The principal dissolved constituents 

remained the same in December 2000. High concentrations of bicarbonate and sodium result from the 

contact of ground water with evaporite minerals 

nahcolite and halite in the Green River Formation. 

Sulfate is commonly high in the ground water of the 

overlying Uinta Formation. Sodium, bicarbonate, and 

chloride concentrations increased gradually (25 to 

35 percent) downstream to PC20,708 as water 

discharged to the stream valley. A substantial increase 

in bicarbonate (19 percent), sodium (35 percent), and 

chloride (89 percent) occurred in the Alkali Flat area, 

of Piceance Creek. Sulfate, calcium, magnesium, 

potassium, silica, and fluoride concentrations 

remained relatively constant throughout the study area.

Concentrations of barium, boron, lithium, and 

strontium were elevated in Piceance Creek. Strontium 

concentrations were the highest but remained relatively constant throughout Piceance Creek. Barium 

and boron concentrations increased from 50 to 65 

percent from upstream to downstream. The largest 

increase in barium and boron concentrations occurred 

in the area of Alkali Flat. Lithium also increased 

substantially between PC17,860 and PC23J21, which 

includes the Alkali Flat area. Concentrations of most 

of the other trace constituents were at or near method 

reporting limits, and little or no downstream increases 

were observed.

No significant load input to Piceance Creek was 

detected along the primary study reach. Although the 

area near Alkali Flat contributed substantially to the 

increase in constituent,concentration in Piceance 

Creek, losses in streamflow along the secondary study 

reach resulted in relatively small increases in load 

downstream to the end of the study reach. Load 

profiles for dissolved cations, anions, and trace 

constituents from PCO to PCI 1,483 were similar to 

streamflow profiles in Piceance Creek for this same 

reach. Overall, the loads increased gradually along the 

primary study reach, and the only substantial increase

28 Baseline Characterization of Water Quality and Mass Loading in Piceance Creek, Rio Blanco County, Colorado, December 2000
in load occurred between PC9,938 and PC 10,748. 

Presumably, increased ground-water inputs to the 

stream resulted in a gradual increase in streamflow as 

the alluvial valley narrows. Along the secondary study 

reach, the increases in ion concentration that were 

observed were offset by decreased streamflow along 

much of the reach. The resulting load profiles for 

dissolved cations, anions, and trace constituents downstream from PC 11,483 showed little or no increase. 

Additional investigation along the secondary study 

reach is needed to substantiate these findings.

REFERENCES CITED

Agapito Associates, Inc., 1999, Groundwater, surface water, 

and process monitoring plan for the Yankee Gulch 

Sodium Minerals Project: prepared for American 

Soda, LLP., Agapito Associates Inc., Grand Junction, 

Colorado, 30 p.

Beard, T.N., Tail, D.B., and Smith, J.W., 1974, Nahcolite 

and dawsonite resources in the Green River Formation, 

Piceance Creek Basin, Colorado: Rocky Mountain 

Association of Geologists 1974 Guidebook.

Colorado Climate Center, 2001, Daily temperature

summary for Rifle, Colorado, for calendar year 2000: 

at URL http://ccc.atmos.colostate.edu

Crowfoot, R.M., Unruh, J.W., Boulger, R.W., and O'Neill, 

B.B., 2001, Water resources data for Colorado, Water 

Year 2000, v. 2, Colorado River Basin: U.S. Geological 

Survey Water-Data Report CO-00-2, 596 p.

 , 2002, Water resources data for Colorado, Water 

Year 2001, v. 2, Colorado River Basin: U.S. Geological 

Survey Water-Data Report CO-01-2, 596 p.

Dyni, J.R., 1987, Origin of the oil shale and associated 

minerals, in Taylor, J.O., ed., Oil shale, water 

resources, and valuable minerals of the Piceance Basin, 

Colorado: U.S. Geological Survey Professional Paper 

1310, p. 17-20.

Donnell, J.R., 1987, Storehouse of energy minerals in the 

Piceance Basin, in Taylor, J.O., ed., Oil shale, water 

resources, and valuable minerals of the Piceance Basin, 

Colorado: U.S. Geological Survey Professional Paper 

1310, p. 21-28.

Grout, M.A., and Verbeek, E.A., 1985, Fracture history of 

the Plateau Creek and adjacent Colorado River valleys, 

southern Piceance Basin-Implications for predicting

joint patterns at depth: U.S. Geological Survey OpenFile Report 85-0744, 17 p.

Horowitz, A.J., Demas, C.R., Fitzgerald, K.K., Miller, T.L., 

and Rickert, D.A., 1994, U.S. Geological Survey 

protocol for the collection and processing of surfacewater samples for the subsequent determination of 

inorganic constituents in filtered water: U.S. Geological Survey Open-File Report 94-539, 57 p.

Kimball, B.A., 1997, Use of tracer injections and synoptic 

sampling to measure loadings from acid mine 

drainage: U.S. Geological Survey Fact Sheet 245-96, 

4 p.

Kimball, B.A., Runkel, R.L., and Gerner, L.J., 1998, Quantification of metal loading in French Gulch, Summit 

County, Colorado, using a tracer-injection study, July 

1996: U.S. Geological Survey Water-Resources 

Investigations Report 98-4078, 38 p.

Maclachlan, M.E., 1987, General geology of the Piceance 

Basin, in Taylor, J.O., ed., Oil shale, water resources, 

and valuable minerals of the Piceance Basin, Colorado: 

U.S. Geological Survey Professional Paper 1310, 

p. 7-17.

Norman, V.W., 1987, Suspended sediment in Piceance 

Creek, in Taylor, J.O., ed., Oil shale, water resources, 

and valuable minerals of the Piceance Basin, Colorado: 

U.S. Geological Survey Professional Paper 1310, 

p. 77-80.

Ortiz, R.F., and Bencala, K.E., 2001, Determination of 

instream metal loads using tracer-injection and 

synoptic-sampling techniques in Wightman Fork, 

Southwestern Colorado, September 1997: U.S. 

Geological Survey Water-Resources Investigations 

Report 00-4154, 26 p.

Pritt, J.W., and Raese, J.W., eds., 1995, Quality assurance/quality control manual National Water Quality 

Laboratory: U.S. Geological Survey Open-File 

Report 95-443, 35 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.

Robson, S.G., and Saulnier, Jr., G.J., 1981, Hydrogeochemistry and simulated solute transport, Piceance Basin, 

Northwest Colorado: U.S. Geological Survey 

Professional Paper 1196, 65 p.

Saulnier, Jr., G.J., and Ford, T.R., 1977, Springs and fractures as an indication of potentially productive wells in 

the Piceance Basin, Northwest Colorado [abs.]: 

Ground Water, v. 15, no. 4, p. 326.

REFERENCES CITED 29
Tobin, R.L., Stranathan, H.E., and Covay, K.J., 1985, Waterquality characteristics of streams in the Piceance Creek 

and Yellow Creek Drainage Basins, Northwestern 

Colorado: U.S. Geological Survey Water-Resources 

Investigations Report 84-4261, 35 p.

Tobin, R.L., 1987, Water quality in the Piceance Basin, in 

Taylor, J.O., ed., Oil shale, water resources, and 

valuable minerals of the Piceance Basin, Colorado: 

U.S. Geological Survey Professional Paper 1310, 

p. 81-86.

U.S. Bureau of Land Management, 1984,

Volume 1 Piceance Basin Resource Management 

Plan and Environmental Impact Statement: U.S. 

Department of the Interior, Bureau of Land Management, White River Resource Area, Colorado, 270 p.

 , 1999, Draft Environmental Impact StatementYankee Gulch Sodium Minerals Project, to produce 

sodium products, Piceance Basin, right-of-way permit 

and COE Section 404 permit, Rio Blanco County, 

Colorado: EIS No. 99004.

Verbeek, E.R., and Grout, M.A., 1983a, Fracture history of 

the northern Piceance Creek basin, northwestern 

Colorado, in Gary, J.H., ed., Oil Shale Symposium 

Proceedings, v. 16, Colorado School of Mines, Golden, 

Colorado, p. 26-44.

1983b, Fracture studies at C-a Mine, Piceance

Creek basin, Colorado: Abstracts with Programs - 

Geological Society of America, v.15, no.5, p. 375 

 , 1987, Systematic joints within oil shales and associated rocks of the Green River Formation, in Taylor, 

J.O., ed., Oil shale, water resources, and valuable 

minerals of the Piceance Basin, Colorado: U.S. 

Geological Survey Professional Paper 1310, p. 45 56.

Ward, J.R., and Harr, C.A., eds., 1990, Methods for collection and processing of surface-water and bed-material 

samples for physical and chemical analyses: U.S. 

Geological Survey Open-File Report 90-140, 71 p.

Welder, F.A., 1987, Unconsolidated deposits of the Piceance 

Basin, in Taylor, J.O., ed., Oil shale, water resources, 

and valuable minerals of the Piceance Basin, Colorado: 

U.S. Geological Survey Professional Paper 1310, 

p. 57-62.

Wilde, F.D., Radtke, D.B., Gibs, J., and Iwatsubo, R.T., eds., 

1998, National field manual for the collection of waterquality data: U.S. Geological Techniques of WaterResources Investigations, book 9, chap. A1-A5.

Zellweger, G.W., Bencala, K.E., McKnight, D.M., Hirsch, 

R.M., and Kimball, B.A., 1988, Practical aspects of 

tracer experiments in acidic, metal enriched stream, in 

Mallard, G.E., ed., U.S. Geological Survey Toxic 

Substances Hydrology Program Surface-Water 

Contamination, Open-File Report 87-764, p. 125-130

30 Baseline Characterization of Water Quality and Mass Loading in Piceance Creek, Rio Blanco County, Colorado, December 2000
DATA SECTION

Table 5. Chemical data for synoptic samples collected in Piceance Creek Basin, December 4-7, 2000

[mg/L, milligrams per liter; HCO3 , bicarbonate; CaCC>3, calcium carbonate; nd, no data; mv, missing value; e, estimated; <, less than; fig/L, microgram

per liter; pCi/L, picocurie per liter]

Site name

Sample collection 

Calcium,

dissolved 

Date Time (mg/L)

Magnesium, 

dissolved 

(mg/L)

Sodium, 

dissolved 

(mg/L)

Potassium, 

dissolved 

(mg/L)

Bicarbonate 

(mg/L as 

HCO3)

Alkalinity 

(mg/L 

as total 

CaC03)

Sulfate, 

dissolved 

(mg/L)

Chloride, 

dissolved 

(mg/L)

Main-stem sites

PCO

PC 180

PC420

PC660

PC 1,080

PC 1,320

PC 1,560

PC 1,960

PC2,205

PC2,445

PC2,685

PC2,925

PCS, 105

PCS ,278

PC3,505

PC3.735

PC3,935

PC4,180

PC4,420

PC4.660

PC4,900

PCS ,040

PC5,280

PC6,625

PC6,625

PC6,8J3

PC7,028

PC7,248

PC7,498

PC7.738

PC7,978

PC8,098

PC8,448

PC8,688

PC8,938

PC9,298

PC9,608

PC9,938

PC 10,328

PC 10,748

PC 11, 483

12-07-00

12-07-00

12-07-00

12-07-00

12-07-00

12-07-00

12-07-00

12-07-00

12-07-00

12-07-00

12-07-00

12-07-00

12-07-00

12-07-00

12-07-00

12-07-00

12-07-00

12-07-00

12-07-00

12-07-00

12-07-00

12-07-00

12-07-00

12-07-00

12-05-00

12-05-00

12-05-00

12-05-00

12-05-00

12-05-00

12-05-00

12-05-00

12-05-00

12-05-00

12-05-00

12-05-00

12-05-00

12-05-00

12-05-00

12-05-00

12-05-00

1040

1035

1030

1020

1015

1005

0955

0945

0935

0925

0920

0910

0900

0845

0835

0825

0815

0800

0755

0745

0735

0727

0700

1147

1040

1020

1010

0955

0945

0935

0930

0915

0905

0855

0850

0825

0815

0805

0800

0745

0730

93

91

92

90

91

94

90

91

87

91

91

94

93

92

92

94

89

88

90

90

93

90

89

88

87

87

87

89

87

88

88

92

87

87

86

85

80

85

82

84

86

79

81

81

80

81

84

82

82

80

83

83

85

85

85

84

85

82

84

82

82

84

81

79

82

84

84

86

87

85

85

86

86

87

86

86

85

82

87

82

83

81

150

160

160

150

160

160

.160

160

160

160

160

170

170

170

170

170

170

180

160

170

170

160

170

180

180

mv

mv

mv

mv

mv

mv

mv

mv

mv

mv

mv

mv

mv

mv

mv

mv

2.4

2.4

2.4

2.4

mv

2.5

2.4

2.4

2.5

2.5

2.4

2.4

2.4

2.5

2.4

2.4

2.5

2.4

2.4

2.4

2.4

2.4

2.4

2.5

2.5

2.3

2.4

2.5

2.4

2.3

2.5

2.4

2.6

2.4

2.4

2.4

2.5

2.5

2.5

2.4

2.5

570

600

560

560

590

590

580

570

600

570

590

600

590

610

600

590

610

610

570

600

610

mv

mv

600

650

660

650

640

660

650

620

660

620

650

620

630

660

680

660

660

670

420

420

420

410

440

440

430

440

470

430

440

420

420

430

440

420

440

470

450

450

450

440

480

450

480

480

460

480

480

470

470

510

480

490

470

480

490

490

500

470

500

390

410

410

410

410

420

410

410

420

410

420

420

420

420

420

410

420

420

410

400

410

410

420

420

410

420

420

420

420

410

420

430

420

420

430

420

410

420

420

430

430

14.9

15.6

15.5

15.0

15.9

14.7

16.2

16.0

16.3

16.3

16.0

16.4

16.4

16.1

16.2

15.2

16.8

16.5

16.6

16.2

14.8

16.2

16.8

17.5

18.1

17.5

18.0

17.9

17.3

17.6

18.0

18.2

18.0

18.0

18.3

18.3

18.4

18.5

18.5

18.6

18.8

DATA SECTION 33
Table 5. Chemical data for synoptic samples collected in Piceance Creek Basin, December 4-7, 2000 Continued 

[mg/L, milligrams per liter; HCO3 , bicarbonate; CaCO3 , calcium carbonate; nd, no data; mv, missing value; e, estimated; <, less than; u,g/L, microgram 

per liter; pCi/L, picocurie per liter]

Site name

Sample collection 

Date Time

_ . . Mag- _ .. Potas- Calcium, . Sodium, 

.. , ' nesium, .. . ' sium, dissolved .. . ' dissolved .. . ' 

, > dissolved . . dissolved

(mg/L) (mg/L) (mg/L) (mg/L)

Bicarbonate 

(mg/L as 

HC03)

Alkalinity 

(mg/L 

as total 

CaCO3)

Sulfate, 

dissolved 

(mg/L)

Chloride, 

dissolved 

(mg/L)

Main-stem sites Continued

PC 14,789

PC16,210

PC17,860

PC20.708

PC23,721

PC24,787

PC28,348

12-06-00

12-06-00

12-06-00

12-06-00

12-06-00

12-06-00

12-06-00

1005

0910

0805

1030

0945

0900

0745

79

84

86

81

81

83

82

85

88

81

83

78

85

87

200

200

200

200

270

270

280

2.5

2.5

2.4

2.5

2.5

2.5

2.6

mv

mv

mv

720

860

800

mv

480

520

520

490

650

590

600

430

430

430

410

410

410

420

19.2

19.1

20.0

20.1

37.9

33.6

34.4

Input sites

RGS

HGS

PT 16,225

AFS

Site name

12-04-00

12-07-00

12-06-00

12-04-00

0900

1220

0925

1225

Sample collection 

Date Time

110

32

73

17

Fluoride, 

dissolved 

(mg/L)

200

100

50

48

Bromide, 

dissolved 

(mg/L)

360

650

110

3,540

Silica, 

dissolved 

(mg/L)

Total 

dissolved 

solids 

(mg/L)

1.8

1.9

2.0

7.3

Nitrite, 

dissolved 

(mg/L)

mv

1,570

370

mv

Nitrite 

plus 

nitrate, 

dissolved 

(mg/L)

640

1,290

330

6,860

Ammonia, 

dissolved 

(mg/L)

1,210

700

240

100

Ammonia 

plus 

organic 

nitrogen, 

dissolved 

(mg/L)

24.9

43.9

15.2

900

Phosphorus, 

dissolved 

(mg/L)

Main-stem sites

PCO

PC 180

PC420

PC660

PC 1,080

PC 1,320

PC 1,560

PC 1,960

PC2,205

PC2,445

PC2,685

PC2,925

PC3,105

PC3,278

PC3,505

PC3J35

PC3,935

PC4,180

PC4,420

PC4,660

PC4,900

PCS, 040

PC5,280

12-07-00

12-07-00

12-07-00

12-07-00

12-07-00

12-07-00

12-07-00

12-07-00

12-07-00

12-07-00

12-07-00

12-07-00

12-07-00

12-07-00

12-07-00

12-07-00

12-07-00

12-07-00

12-07-00

12-07-00

12-07-00

12-07-00

12-07-00

1040

1035

1030

1020

1015

1005

0955

0945

0935

0925

0920

0910

0900

0845

0835

0825

0815

0800

0755

0745

0735

0727

0700

0.61

.93

.59

.59

.63

.59

.59

.62

.67

.94 

.61

.60

.59

.60

.92

.60

1.19

.68

.64

.62

.63

.61

.59

0.10

mv

mv

mv

mv

mv

mv

mv

mv

mv

mv

mv

mv

mv

mv

mv

mv

mv

mv

mv

mv

mv

mv

16.4

16.6

16.6

16.5

16.6

16.6

16.8

16.7

17.0

16.7

16.9

16.5

17.0

16.8

17.7

16.4

16.6

16.8

16.6

16.5

16.7

16.5

16.5

1,000

1,030

1,030

1,020

1,050

1,060

1,040

1,050

1,080

1,050

1,060

1,060

1,060

1,060

1,070

1,050

1,060

1,100

1,050

1,050

1,070

1,050

1,100

nd

nd

nd

nd

nd

nd

nd

nd

.01

nd

nd

nd

nd

nd

nd

nd

nd

.01

nd

nd

nd

nd

.01

nd

nd

nd

nd

nd

nd

nd

nd

.69

nd

nd

nd

nd

nd

nd

nd

nd

.67

nd

nd

nd

nd

.66

nd

nd

nd

nd

nd

nd

nd

nd

e.04

nd

nd

nd

nd

nd

nd

nd

nd

e.04

nd

nd

nd

nd

.05

nd

nd

nd

nd

nd

nd

nd

nd

.28

nd

nd

nd

nd

nd

nd

nd

nd

.30

nd

nd

nd

nd

.32

nd

nd

nd

nd

nd

nd

nd

nd

<.06

nd

nd

nd

nd

nd

nd

nd

nd

<.06

nd

nd

nd

nd

<.06

34 Baseline Characterization of Water Quality and Mass Loading in Piceance Creek, Rio Blanco County, Colorado, December 2000
Table 5. Chemical data for synoptic samples collected in Piceance Creek Basin, December 4-7, 2000 Continued 

[mg/L, milligrams per liter; HC03 , bicarbonate; CaC03 , calcium carbonate; nd, no data; mv, missing value; e, estimated; <, less than; (ig/L, microgram 

per liter; pCi/L, picocurie per liter]

Sample collection _ _ . . _. . . Bro- _.,. Total Fluonde, . . Silica, .. 

.. mide, .. dis- 

... dis- .. dis- . . Site name . . dis- . . solved Date Time solved so)ved solved so|jds

(mg/L) (mg/L) (mg/L) (mg/L)

Nitrite, 

dissolved 

(mg/L)

Nitrite Ammonia

plus plus !7 . monia, nitrate, organic

dis' solved nitr°9en ' 

solved . . dissolved

(mg/L) (mg/L) (mg/L)

Phosphorus, 

dissolved 

(mg/L)

Main-stem sites Continued

PC6,625

PC6,625

PC6,813

PC7,028

PC7,248

PC7,498

PC7J38

PC7,978

PC8,098

PC8,448

PC8.688

PCS, 93 8

PC9,298

PC9,608

PC9,938

PC 10,328

PC 10,748

PC 11, 483

PC 14,789

PC16,210

PC 17,860

PC20J08

PC23J21

PC24,787

PC28,348

RGS

HGS

PT 16,225

AFS

Site name

12-07-00

12-05-00

12-05-00

12-05-00

12-05-00

12-05-00

12-05-00

12-05-00

12-05-00

12-05-00

12-05-00

12-05-00

12-05-00

12-05-00

12-05-00

12-05-00

12-05-00

12-05-00

12-06-00

12-06-00

12-06-00

12-06-00

12-06-00

12-06-00

12-06-00

12-04-00

12-07-00

12-06-00

12-04-00

1147 0.59

1040 1

1020

1010

0955

0945

0935

0930

0915

0905

0855

0850

0825

0815

0805

0800

0745

0730

1005

0910

0805

1030

0945

0900

0745

0900

1220 2

0925

1225 15

.15

.60

.65

.66

.66

.57

.64

.69

.64

.58

.62

.67

.66

.69

.63

.66

.69

.64

.67

.68

.67

.90

.86

.79

.37

.77

.40

.5

Sample collection Orthophosphorus, 

Date Time disso|ved

(mg/L)

mv

mv

mv

mv

mv

mv

mv

mv

mv

mv

mv

mv

mv

mv

mv

mv

mv

mv

.10

.09

.12

.09

.12

.13

.19

.20

.20

.11

.69

Aluminum, 

dissolved

16.5

16.7

16.6

16.7

16.7

16.6

16.5

15.3

16.5

18.2

16.9

16.0

16.6

16.1

16.6

15.9

17.0

16.8

17.0

16.8

17.0

16.8

16.9

16.4

17.3

21.6

15.5

16.4

.8

1,080

1,100

1,100

1,100

1,110

1,100

1,090

1,110

1,160

1,120

1,120

1,120

1,110

1,100

1,130

1,110

1,110

1,150

1,130

1,160

1,150

1,110

1,300

1,260

1,290

Input sites

2,310

2,330

710

8,760

AntiArsenic, mony, .. . ' 

.. , ' dissolved dissolved . .. . 

. . (ua/L) (ng/L)

nd

nd

nd

nd

nd

nd

' nd

nd

.01

nd

nd

nd

nd

nd

nd

nd

nd

.01

nd

nd

.01

nd

.01

nd

nd

nd

nd

nd

nd

Barium, 

dissolved

nd

nd

nd

nd

nd

nd

nd

nd

.66

nd

nd

nd

nd

nd

nd

nd

nd

.61

nd

nd

.70

nd

.67

nd

nd

nd

nd

nd

nd

Beryllium, 

dissolved

nd

nd

nd

nd

nd

nd

nd

nd

.06

nd

nd

nd

nd

nd

nd

nd

nd

.06

nd

nd

.06

nd .

.15

nd

nd

nd

nd

nd

nd

Boron, 

dissolved

nd

nd

nd

nd

nd

nd

nd

nd

.32

nd

nd

nd

nd

nd

nd

nd

nd

.33

nd

nd

.37

nd

.49

nd

nd

nd

nd

nd

nd

Cadmium, 

dissolved

nd

nd

nd

nd

nd

nd

nd

nd

<.06

nd

nd

nd

nd

nd

nd

nd

nd

<.06

nd

nd

<.06

nd

e.05

nd

nd

nd

nd

nd

nd

Chromium, 

dissolved

Main-stem sites

PCO

PC 180

PC420

PC660

PC 1,080

PC 1,320

12-07-00 1040 nd

12-07-00 1035 nd

12-07-00 1030 nd

12-07-00 1020 nd

12-07-00 1015 nd

12-07-00 1005 nd

mv

mv

mv

mv

mv

mv

0.11

.16

.12

.13

.13

.12

1.7

1.2

1.2

1.2

1.1

1.2

75

73

73

72

73

74

nd

nd

nd

nd

nd

nd

160

160

160

160

160

170

nd

nd

nd

nd

nd

nd

nd

nd

nd

nd

nd

nd

DATA SECTION 35
Table 5. Chemical data for synoptic samples collected in Piceance Creek Basin, December 4-7, 2000 Continued 

[mg/L, milligrams per liter; HCO3 , bicarbonate; CaCO3 , calcium carbonate; nd, no data; mv, missing value; e, estimated; <, less than; (ig/L, microgram 

per liter; pCi/L, picocurie per liter]

Site name

Sample collection Orthophosphorus, 

Date Time disso|ved

(mg/L)

Aluminum, 

dissolved

Antimony, 

dissolved

(ng/L)

Arsenic, 

dissolved 

(fig/L)

Barium, 

dissolved

Beryllium, 

dissolved

CadBoron, 

.. . ' mium, dissolved .. . ' dissolved

Chromium, 

dissolved 

(l-ig/L)

Main-stem sites Continued

PC 1,560

PC 1,960

PC2,205

PC2,445

PC2,685

PC2,925

PC3,105

PC3,278

PC3,505

PC3,735

PC3,935

PC4, 1 80

PC4,420

PC4,660

PC4,900

PC5,040

PC5,280

PC6,625

PC6,625

PC6,813

PC7,028

PC7,248

PC7,498

PC7.738

PC7,978

PC8,098

PC8,448

PC8,688

PC8,938

PC9,298

PC9,608

PC9,938

PC 10,328

PC 10,748

PC 11, 483

PC 14,789

PC16,210

PC 17,860

PC20J08

PC23.721

PC24.787

PC28,348

12-07-00

12-07-00

12-07-00

12-07-00

12-07-00

12-07-00

12-07-00

12-07-00

12-07-00

12-07-00

12-07-00

12-07-00

12-07-00

12-07-00

12-07-00

12-07-00

12-07-00

12-07-00

12-05-00

12-05-00

12-05-00

12-05-00

12-05-00

12-05-00

12-05-00

12-05-00

12-05-00

12-05-00

12-05-00

12-05-00

12-05-00

12-05-00

12-05-00

12-05-00

12-05-00

12-06-00

12-06-00

12-06-00

12-06-00

12-06-00

12-06-00

12-06-00

0955

0945

0935

0925

0920

0910

0900

0845

0835

0825

0815

0800

0755

0745

0735

0727

0700

1147

1040

1020

1010

0955

0945

0935

0930

0915

0905

0855

0850

0825

0815

0805

0800

0745

0730

1005

0910

0805

1030

0945

0900

0745

nd

nd

0.02

nd

nd

nd

nd

nd

nd

nd

nd

.02

nd

nd

nd

nd

.02

nd

nd

nd

nd

nd

nd

nd

nd

.04

nd

nd

nd

nd

nd

nd

nd

nd

.05

nd

nd

.03

nd

.06

nd

nd

mv

mv

mv

mv

mv

mv

mv

mv

mv

mv

mv

mv

mv

mv

mv

mv

mv

mv

<1.0

1.1

1.0

2.2

1.6

1.1

1.3

1.1

1.3

<1.0

2.7

1.7

<1.0

<1.0

2.3

1.4

<1.0

1.2

1.5

<1.0

1.3

<1.0

1.2

1.2

0.13

.12

.12

.11

.12

.12

.11

.19

.15

.11

.11

.12

.13

.12

.12

.12

.12

.12

.11

.13

.12

<.05

<.05

.12

<.05

.13

<.05

.12

<.05

<.05

.11

.12

<.05

.16

.13

.18

<.05

.13

<.05

.14

<.05

.17

1.2

1.2

e2.0

1.1

1.3

1.3

1.4

1.4

1.3

1.3

1.5

2.1

1.4

1.5

1.3

1.4

e 1.9

1.5

1.7

2.1

1.6

2.3

2.2

2.3

2.3

e 1.9

2.4

2.4

2.4

2.4

1.3

1.6

2.5

1.6

e 1.9

2.0

2.4

e 1.7

2.2

e 1.8

2.6

2.0 

72

74

74

73

74

73

73

73

73

74

74

75

74

74

73

73

76

86

78

78

74

80

78

78

78

79

78

78

79

78

72

74

77

78

81

79

79

81

82

110

100

100

nd

nd

<0.06

nd

nd

nd

nd

nd

nd

nd

nd

<.06

nd

nd

nd

nd

<.06

nd

nd

nd

nd

nd

nd

nd

nd

<.06

nd

nd

nd

nd

nd

nd

nd

nd

<.06

nd

nd

<.06

nd

<.06

nd

nd

160

160

170

170

170

180

170

160

170

170

170

200

160

170

170

160

170

170

190

180

180

190

180

180

190

190

190

180

190

190

180

200

190

180

180

190

190

190

190

220

230

260

nd

nd

0.04

nd

nd

nd

nd

nd

nd

nd

nd

.04

nd

nd

nd

nd

.05

nd

nd

nd

nd

nd

nd

nd

nd

.59

nd

nd

nd

nd

nd

nd

nd

nd

e.03

nd

nd

e.03

nd

.20

nd

nd

nd

nd

<0.8

nd

nd

nd

nd

nd

nd

nd

nd

<.8

nd

nd

nd

nd

<.8

nd

nd

nd

nd

nd

nd

nd

nd

<.8

nd

nd

nd

nd

nd

nd

nd

nd

<.8

nd

nd

e.5

nd

<.8

nd

nd

36 Baseline Characterization of Water Quality and Mass Loading in Piceance Creek, Rio Blanco County, Colorado, December 2000
Table 5. Chemical data for synoptic samples collected in Piceance Creek Basin, December 4-7, 2000 Continued 

[mg/L, milligrams per liter; HC03 , bicarbonate; CaCO3 , calcium carbonate; nd, no data; mv, missing value; e, estimated; <, less than; |J.g/L, microgram 

per liter; pCi/L, picocurie per liter]

Sample collection Ortho- ., . .. 

. Alum- Anti- A . _ . _ ... phos- . Arsenic, Barium, Beryllium,

Site name phorus, .. . ' . .. . . dissolved dissolved dissolved Date Time .. , . disso ved dissolved . . . . . .. . dissolved , ., . . . (ug/L) (ug/L) (ug/L) ((jg/L) ((jg/L)

Input sites

RGS 12-04-00 0900 nd 2.5 .05 1.9 21 

HGS 12-07-00 1220 nd mv .05 7.6 56 

PT 16,225 12-06-00 0925 nd <1.0 .16 1.9 71 

AFS 12-04-00 1225 nd 4.4 <.05 2.2 4,740

Site name

PCO

PC 180

PC420

PC660

PC 1,080

PC 1,320

PC1.560

PC 1,960

PC2,205

PC2,445

PC2,685

PC2,925

PC3,105

PC3,278

PC3,505

PC3,735

PC3,935

PC4,180

PC4,420

PC4,660

PC4,900

PC5,040

PC5,280

PC6,625

PC6,625

PC6,813

PC7,028

PC7,248

PC7,498

PC7,738

PC7,978

PC8,098

PC8,448

Sample collection 

Date Time

12-07-00

12-07-00

12-07-00

12-07-00

12-07-00

12-07-00

12-07-00

12-07-00

12-07-00

12-07-00

12-07-00

12-07-00

12-07-00

12-07-00

12-07-00

12-07-00

12-07-00

12-07-00

12-07-00

12-07-00

12-07-00

12-07-00

12-07-00

12-07-00

12-05-00

12-05-00

12-05-00

12-05-00

12-05-00

12-05-00

12-05-00

12-05-00

12-05-00

1040

1035

1030

1020

1015

1005

0955

0945

0935

0925

0920

0910

0900

0845

0835

0825

0815

0800

0755

0745

0735

0727

0700

1147

1040

1020

1010

0955

0945

0935

0930

0915

0905

Cobalt, 

dissolved

nd

nd

nd

nd

nd

nd

nd

nd

0.49

nd

nd

nd

nd

nd

nd

nd

nd

.49

nd

nd

nd

nd

.50

nd

nd

nd

nd

nd

nd

nd

nd

.50

nd

Copper, 

dissolved

nd

nd

nd

nd

nd

nd

nd

nd

2.2

nd

nd

nd

nd

nd

nd

nd

nd

. 2.3

nd

nd

nd

nd

2.2

nd

nd

nd

nd

nd

nd

nd

nd

2.0

nd

Iron, . . .. 

.. Lead, dis- dis- . 

. . solved solved

Main-stem sites

<10 nd

<10 nd

<10 nd

<10 nd

<10 nd

<10 nd

<10 nd

<10 nd

<10 <0.08

<10 nd

<10 nd

<10 nd

<10 nd

<10 nd

<10 nd

<10 nd

<10 nd

<10 <.08

<10 nd

<10 nd

<10 nd

<10 nd

e6.3 <.08

<10 nd

<10 nd

<10 nd

<10 nd

<10 nd

<10 nd

<10 nd

<10 nd

<10 <.08

<10 nd

Lithium, 

dissolved 

(^9/L)

nd

nd

nd

nd

nd

nd

nd

nd

mv

nd

nd

nd

nd

nd

nd

nd

nd

mv

nd

nd

nd

nd

mv

nd

nd

nd

nd

nd

nd

nd

nd

12.3

nd

nd 

nd 

nd 

nd

Manganese, 

dissolved 

(u,g/L)

nd

nd

nd

nd

nd

nd

nd

nd

85

nd

nd

nd

nd

nd

nd

nd

nd

83

nd

nd

nd

nd

82

nd

nd

nd

nd

nd

nd

nd

nd

84

nd

Boron, 

dissolved

330 

560 

120 

1,160

Mercury, 

dissolved

nd

nd

nd

nd

nd

nd

nd

nd

<0.23

nd

nd

nd

nd

nd

nd

nd

nd

<.23

nd

nd

nd

nd

<.23

nd

nd

nd

nd

nd

nd

nd

nd

<.23

nd

Cadmium, 

dissolved

nd 

nd 

nd 

nd

Molybdenum, 

dissolved

(ng/L)

nd

nd

nd

nd

nd

nd

nd

nd

7.9

nd

nd

nd

nd

nd

nd

nd

nd

8.1

nd

nd

nd

nd

7.9

nd

nd

nd

nd

nd

nd

nd

nd

8.5

nd

Chromium, 

dissolved

nd 

nd 

nd 

nd

Nickel, 

dissolved

nd

nd

nd

nd

nd

nd

nd

nd

2.6

nd

nd

nd

nd

nd

nd

nd

nd

2.6

nd

nd

nd

nd

2.7

nd

nd

nd

nd

nd

nd

nd

nd

1.3

nd

DATA SECTION 37
Table 5. Chemical data for synoptic samples collected in Piceance Creek Basin, December 4-7, 2000 Continued 

[mg/L, milligrams per liter; HCO3 , bicarbonate; CaCO3 , calcium carbonate; nd, no data; mv, missing value; e, estimated; <, less than; |ig/L, microgram 

per liter; pCi/L, picocurie per liter]

Sample collection

Site name Date Time

Cobalt, Copper, Iron, 

dis- dis- dissolved solved solved 

(ug/L) (ug/L) (ug/L)

LithLead, dis- ium, 

solved dis- 

(ug/L) solved 

(ug/L)

Manganese, 

dissolved 

(ug/L)

Mercury, 

dissolved 

(ug/L)

Molybdenum, 

dissolved 

(ug/L)

Nickel, 

dissolved 

(ug/L)

Main-stem sites Continued

PC8,688

PC8,938

PC9,298

PC9,608

PC9,938

PC 10,328

PC 10,748

PC 11, 483

PC 14,789

PC16,210

PC17,860

PC20,708

PC23.721

PC24,787

PC28,348

RGS

HGS

PT1 6,225

AFS

Site name

12-05-00

12-05-00

12-05-00

12-05-00

12-05-00

12-05-00

12-05-00

12-05-00

12-06-00

12-06-00

12-06-00

12-06-00

12-06-00

12-06-00

12-06-00

12-04-00

12-07-00

12-06-00

12-04-00

0855

0850

0825

0815

0805

0800

0745

0730

1005

0910

0805

1030

0945

0900

0745

0900

1220

0925

1225

nd

nd

nd

nd

nd

nd

nd

0.52

nd

nd

.50

nd

.54

nd

nd

nd

nd

nd

nd

Sample collection

OGlG"

nium, 

Date Time dissolved 

(H9/L)

nd

nd

nd

nd

nd

nd

nd

2.0

nd

nd

2.0

nd

2.0

nd

nd

nd

nd

nd

nd

Silver, 

dissolved 

(ug/L)

<10

<10

<10

<10

<10

<10

<10

<10

<10

<10

<10

<10

<10

<30

<30

nd

nd

nd

nd

nd

nd

nd

<0.08

nd

nd

<.08

nd

e.04

nd

nd

Input sites

30 nd

e27

<10

<100

Strontium, 

dissolved 

(ug/L)

nd

nd

nd

Vanadium, 

dissolved 

(ug/L)

nd

nd

nd

nd

nd

nd

nd

11.9

nd

nd

12.8

nd

21.7

nd

nd

nd

nd

nd

nd

Zinc, dissolved

(ug/L)

nd

nd

nd

nd

nd

nd

nd

79

nd

nd

74

nd

72

nd

nd

nd

nd

nd

nd

Grossalpha 

radioactivity 

(PCi/L)

nd

nd

nd

nd

nd

nd

nd

<0.23

nd

nd

<.23

nd

<.23

nd

nd

nd

nd

nd

nd

Grossbeta 

radioactivity, 

(pCi/L)

nd

nd

nd

nd

nd

nd

nd

8.8

nd

nd

9.0

nd

8.4

nd

nd

nd

nd

nd

nd

Uranium, 

natural, 

dissolved 

((ug/L)

nd

nd

nd

nd

nd

nd

nd

1.4

nd

nd

1.0

nd

1.2

nd

nd

nd

nd

nd

nd

Organic 

carbon, 

dissolved 

(mg/L)

Main-stem sites

PCO

PC 180

PC420

PC660

PC 1,080

PC 1,320

PC 1,560

PC 1,960

PC2,205

PC2.445

PC2,685

PC2,925

PC3,105

PC3,278

PC3,505

PC3.735

12-07-00

12-07-00

12-07-00

12-07-00

12-07-00

12-07-00

12-07-00

12-07-00

12-07-00

12-07-00

12-07-00

12-07-00

12-07-00

12-07-00

12-07-00

12-07-00

1040

1035

1030

1020

1015

1005

0955

0945

0935

0925

0920

0910

0900

0845

0835

0825

nd

nd

nd

nd

nd

nd

nd

nd

el.5

nd

nd

nd

nd

nd

nd

nd

nd

nd

nd

nd

nd

nd

nd

nd

<1

nd

nd

nd

nd

nd

nd

nd

2,880

2,940

2,970

2,910

2,950

3,050

2,990

3,000

3,020

3,010

3,030

3,100

3,100

3,080

3,040

3,070

nd

nd

nd

nd

nd

nd

nd

nd

e4.2

nd

nd

nd

nd

nd

nd

nd

1.6

2.0

2.3

2.5

1.8

2.1

2.0

1.8

2.3

2.3

2.3

1.5

1.8

2.0

1.5

1.7

nd

nd

nd

nd

nd

nd

nd

nd

3.1

nd

nd

nd

nd

nd

nd

nd

nd

nd

nd

nd

nd

nd

nd

nd

<4.0

nd

nd

nd

nd

nd

nd

nd

nd

nd

nd

nd

nd

nd

nd

nd

3.5

nd

nd

nd

nd

nd

nd

nd

nd

nd

nd

nd

nd

nd

nd

nd

3.6

nd

nd

nd

nd

nd

nd

nd

38 Baseline Characterization of Water Quality and Mass Loading in Piceance Creek, Rio Blanco County, Colorado, December 2000
Table 5. Chemical data for synoptic samples collected in Piceance Creek Basin, December 4-7, 2000 Continued 

[mg/L, milligrams per liter; HCO3 , bicarbonate; CaCO3 , calcium carbonate; nd, no data; mv, missing value; e, estimated; <, less than; |ig/L, microgram 

per liter; pCi/L, picocurie per liter]

Site name

Sample collection 

Date Time

Selenium, 

dissolved

Silver, 

dissolved

Strontium, 

dissolved

Vanadium, 

dissolved

GrossZinc, dis- alpha 

solved radio- 

(l-ig/L) activity 

(PCi/L)

Grossbeta 

radioactivity, 

(pCi/L)

Uranium, 

natural, 

dissolved

Organic 

carbon, 

dissolved 

(mg/L)

Main-stem sites Continued

PC3,935

PC4,180

PC4,420

PC4.660

PC4,900

PC5,040

PC5,280

PC6,625

PC6,625

PC6,813

PC7,028

PC7,248

PC7,498

PC7.738

PC7,978

PC8,098

PCS, 448

PC8.688

PC8,938

PC9,298

PC9,608

PC9,938

PC 10,328

PC 10,748

PC 11, 483

PC 14,789

PC16,210

PC 17,860

PC20,708

PC23.721

PC24,787

PC28,348

RGS

HGS

PT1 6,225

AFS

12-07-00

12-07-00

12-07-00

12-07-00

12-07-00

12-07-00

12-07-00

12-07-00

12-05-00

12-05-00

12-05-00

12-05-00

12-05-00

12-05-00

12-05-00

12-05-00

12-05-00

12-05-00

12-05-00

12-05-00

12-05-00

12-05-00

12-05-00

12-05-00

12-05-00

12-06-00

12-06-00

12-06-00

12-06-00

12-06-00

12-06-00

12-06-00

12-04-00

12-07-00

12-06-00

12-04-00

0815

0800

0755

0745

0735

0727

0700

1147

1040

1020

1010

0955

0945

0935

0930

0915

0905

0855

0850

0825

0815

0805

0800

0745

0730

1005

0910

0805

1030

0945

0900

0745

0900

1220

0925

1225

nd

<2.4

nd

nd

nd

nd

<2.4

na

nd

na

na

na

na

na

na

e 1.4

na

na

na

na

na

na

na

na

<2.4

na

na

e 1.6

na

<2.4

na

na

na

na

na

na

nd

<1

nd

nd

nd

nd

<1

na

nd

na

na

na

na

na

na

<1

na

na

na

na

na

na

na

na

<1

na

na

<1

na

<1

na

na

na

na

na

na

2,990

3,390

2,940

3,000

3,040

2,930

3,140

2,960

2,970

2,970

3,020

3,070

2,990

3,020

3,060

3,350

3,060

3,020

2,980

2,950

2,900

2,990

2,880

2,930

3,120

2,980

3,000

3,050

2,810

2,860

2,840

2,880

nd

e7.5

nd

nd

nd

nd

e6.9

na

nd

na

na

na

na

na

na

e6.4

na

na

na

na

na

na

na

na

e4.7

na

na

e5.0

na

e6.2

na

na

Input sites

6,930 na

3,000

1,590

4,070

na

na

na

1.9

1.9

1.5

2.0

2.4

1.9

2.0

1.6

2.2

1.6

1.3

2.0

2.5

1.6

1.8

2.2

2.1

1.5

2.2

2.3

1.1

1.4

2.8

1.9

1.6

1.7

2.4

1.3

2.0

1.5

1.9

1.6

6.0

2.0

<1.0

6.7

nd

3.8

nd

nd

nd

nd

5.0

na

nd

na

na

na

na

na

na

3.8

na

na

na

na

na

na

na

na

<3.0

na

na

4.3

na

3.0

na

na

na

na

na

na

nd

<4.0

nd

nd

nd

nd

<4.0

na

nd

na

na

na

na

na

na

<4.0

na

na

na

na

na

na

na

na

8.8

na

na

<4.0

na

<4.0

na

na

na

na

na

na

nd

3.5

nd

nd

nd

nd

3.5

na

nd

na

na

na

na

na

na

3.6

na

na

na

na

na

na

na

na

3.6

na

na

3.8

na

3.7

na

na

na

na

na

na

nd

3.9

nd

nd

nd

nd

3.7

na

nd

na

na

na

na

na

na

3.8

na

na

na

na

na

na

na

na

3.9

na

na

4.0

na

4.3

na

na

na

na

na

na

DATA SECTION 39
Table 6. Comparison of selected constituent concentrations for duplicate water-quality samples collected in Piceance Creek 

Basin, December 4-7, 2000

[RPD, relative percent difference; mg/L, milligram per liter; |lg/L, microgram per liter; NA, not applicable]

Dissolved 

constituent

Calcium, mg/L

Magnesium, mg/L

Potassium, mg/L

Chloride, mg/L

Silica, mg/L

Sulfate, mg/L

Aluminum, |J.g/L

Barium, |ig/L

Boron, jlg/L

Strontium, |lg/L

Bromide, mg/L

Site PC3,305 

12/7/00 at 0835 and 0836

Concentration

92

92

84

84

2.4

2.5

16

16

18

16

420

420

5.8

7.0

73

74

170

170

3,040

3,040

1.59

1.43

RPD<2 >

0

0

4.1

0

11

0

19

1.4

0

0

11

Site PC8,448 

12/5/00 at 0905 and 0906

Concentration

87

87

87

86

2.6

2.4

18

18

18

17

420

420

1.3

1.4

78

78

190

190

3,060

3,010

1.98

1.86

RPD<2>

0

1.1

8.0

0

5.7

0

7.4

0

0

1.7

6.2

Site BURKE1 

12/4/00 at 1035 and 

1036

Concentration

54

54

68

68

1. 4

1.4

8.1

8.1

20

20

340

340

<1

<1

38

38

120

120

2,060

2,070

.07

.08

RPD<2 >

0

0

0

0

0

0

NA

0

0

.5

13

Site PC28.348 

1 2/6/00 at 0745 and 

0746

Concentration

82

82

87

87

2.6

2.6

34

34

17

16

420

420

1.2

2.5

100

100

260

240

2,880

2,850

.18

.18

RPD<2 >

0

0

0

0

6.1

0

70

0

8.0

1.0

0

1 The site BURKE was a domestic well. Although the site is not incorporated in the text of the report, these data do provide an 

adequate measurement of sample bias and are included in this table.

Relative percent difference is calculated by dividing the absolute value of the concentration difference by the mean of the concentrations. The quotient is shown as a percentage.

40 Baseline Characterization of Water Quality and Mass Loading in Piceance Creek, Rio Blanco County, Colorado, December 2000
Table 7. Water-quality data for field blanks processed December 5 and December 7, 2000

Field parameter

or 

dissolved constituent

Processed after

site PC8,098

12/5/00 at 0915

Processed after

site PC2,205

12/7/00 at 0935

pH, standard unit

Specific conductance, microsiemens per centimeter

Calcium, milligram per liter

Magnesium, milligram per liter

Sodium, milligram per liter

Potassium, milligram per liter

Alkalinity, milligram per liter

Sulfate, milligram per liter

Chloride, milligram per liter

Fluoride, milligram per liter

Silica, milligram per liter

Aluminum, microgram per liter

Antimony, microgram per liter

Arsenic, microgram per liter

Barium, microgram per liter

Boron, microgram per liter

Iron, microgram per liter

Strontium, microgram per liter

Zinc, microgram per liter

7.7

3.9

<.011

<.008

<.06

<.09

2.0

<.ll

<.08

<.16

<.48

<1

<.048

<.18

<1

<13

<10

<.8

<1

7.9

4.0

.011

<.008

<.06

<.09

1.6

<.ll

<.08

<.16

<.48

6.3

<.048

<.18

<1

<13

<10

<.8

5.1

DATA SECTION 41

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