Water Quality, Fish Tissue, and Bed Sediment 

Monitoring in Waterbodies of Fort Chaffee Maneuver 

Training Center, Arkansas, 2002-2004

Prepared in cooperation with the

ARKANSAS ARMY NATIONAL GUARD

U.S. Department of the Interior

U.S. Geological Survey

Scientific Investigations Report 2004-5273
A

B

C

Front cover: 

A- Vache Grasse Creek near Lavaca, Arkansas

B - Big Creek at Potato Hill Road (near Charleston), Fort Chaffee, Arkansas

C - U.S. Geological Survey employee servicing a water-quality monitor at Vache Grasse Creek near

Lavaca, Arkansas

All photographs by David A. Freiwald, U.S. Geological Survey.
Water Quality, Fish Tissue, and Bed 

Sediment Monitoring in Waterbodies of Fort 

Chaffee Maneuver Training Center, 

Arkansas, 2002-2004

By B.G. Justus and Gregory P. Stanton

U.S. Department of the Interior

U.S. Geological Survey

Prepared in cooperation with the

ARKANSAS ARMY NATIONAL GUARD

Scientific Investigations Report 2004-5273
U.S. Department of the Interior

Gale A. Norton, Secretary

U.S. Geological Survey

Charles G. Groat, Director

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

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Contents

 iii

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

Introduction ............................................................................................................................................................................................... 2

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

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

Acknowledgments ........................................................................................................................................................................ 2

Methods ..................................................................................................................................................................................................... 3

Quality Assurance/Quality Control............................................................................................................................................. 5

Water Quality ................................................................................................................................................................................. 5

Fish Tissue ...................................................................................................................................................................................... 7

Bed Sediment ................................................................................................................................................................................ 9

Continuous Monitoring................................................................................................................................................................. 9

Constituents Detected in Water, Fish Tissue, and Bed Sediment ................................................................................................... 9

Water Quality ................................................................................................................................................................................. 9

Fish Tissue .................................................................................................................................................................................... 22

Bed Sediment .............................................................................................................................................................................. 25

Possible Relations of Sediment Deposition to Erosion and Turbidity............................................................................................ 25

Effects of Land Use Both On and Off Post.......................................................................................................................................... 25

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

References .............................................................................................................................................................................................. 29

Appendix 1. Sampling details and field parameters for lake sampling sites at Fort Chaffee, Arkansas, 2002 through

2003 ........................................................................................................................................................................................... 33

Appendix 2. Sampling details and results for field and laboratory constituents measured at stream sampling sites on

Fort Chaffee, Arkansas, 2002 through 2004 ........................................................................................................................ 34

Appendix 3. Daily mean values for stream stage data at Vache Grasse Creek Site 2 from November 2003 to July 2004 ... 35

Appendix 4. Daily mean values for water temperature data at Vache Grasse Creek Site 2 from November 2003 to

July 2004................................................................................................................................................................................... 36

Appendix 5. Daily mean values for specific conductance at Vache Grasse Creek Site 2 from November 2003 to July

2004 ........................................................................................................................................................................................... 37

Appendix 6. Daily mean values for turbidity data at Vache Grasse Creek Site 2 from November 2003 to July 2004 ............ 38

Figures

1. Map showing Fort Chaffee boundaries and training ordnance-impact area and sampling sites.................................. 4

2. Graph showing continuous stage, specific conductance, and turbidity data collected at Vache Grasse Creek

Site 2, April 2004 ........................................................................................................................................................................ 21
iv 

Tables

1. Sampling site information for sites at Fort Chaffee, Arkansas, 2002 through 2004 ............................................................... 3

2. Constituents analyzed in water samples collected at Fort Chaffee, Arkansas, 2002 through 2004 ................................... 6

3. Characteristics of fish collected for tissue (fillet and liver) analysis at Fort Chaffee, Arkansas, 2002 .............................. 7

4. Constituents analyzed in bed sediment and fish tissue samples collected from lakes and streams at Fort Chaffee,

Arkansas, 2002 ................................................................................................................................................................................. 8

5. Concentrations of organic compounds detected in water samples collected at Fort Chaffee, Arkansas,

2002 through 2004 .......................................................................................................................................................................... 10

6. Trace element concentrations for water samples collected at Fort Chaffee, Arkansas, 2002 through 2004 ................. 11

7. Nutrient and other selected constituents detected in water samples collected at Fort Chaffee, Arkansas,

2002 through 2004........................................................................................................................................................................... 16

8. Flow volumes and event mean concentrations for constituents detected above the laboratory minimum detection

limit at four sites for the same storm event at Fort Chaffee, Arkansas, May 2003............................................................. 18

9. Computed storm loads for stream sites sampled at Fort Chaffee, Arkansas, May 2003.................................................... 19

10. A comparison of actual storm loads measured at Vache Grasse Creek Site 0 to flow-normalized storm loads

at Big Creek Site 4, May 2003 ...................................................................................................................................................... 20

11. Concentrations of organic compounds detected in fish fillets collected at Fort Chaffee, Arkansas, 2002.................... 22

12. Trace element concentrations in fish livers collected at Fort Chaffee, Arkansas, 2002 ................................................... 23

13. Trace element concentrations in fish fillets collected at Fort Chaffee, Arkansas, 2002 ................................................... 24

14. Organic compounds detected in bed-sediment samples at Fort Chaffee, Arkansas, 2002 .............................................. 25

15. Concentrations and associated toxicity values for trace elements analyzed in bed-sediment samples collected

at Fort Chaffee, Arkansas, 2002.................................................................................................................................................. 26
Water Quality, Fish Tissue, and Bed Sediment Monitoring 

in Waterbodies of Fort Chaffee Maneuver Training Center, 

Arkansas, 2002-2004

By B.G. Justus and Gregory P. Stanton

Abstract

The Fort Chaffee Maneuver Training Center is a facility 

used to train as many as 50,000 Arkansas National Guardsmen 

each year. Due to the nature of ongoing training and also to a 

poor understanding of environmental procedures that were 

practiced in the World War II era, areas within Fort Chaffee 

have the potential to be sources of a large number of contaminants. Because some streams flow on to Fort Chaffee, there is 

also the potential for sources that are off post to affect environmental conditions on post. This study evaluates constituent concentrations in water, fish tissue, and bed sediment collected 

from waterbodies on Fort Chaffee between September 2002 and 

July 2004. Constituent concentrations detected in the three 

media and measured at nine stream sites and four lake sites were 

compared to national and regional criteria when available. Two 

of the larger streams, Big and Vache Grasse Creeks, were sampled at multiple sites. All three sampled media were analyzed 

for insecticides, PCBs, explosives, and trace elements. Additionally, water samples were analyzed for nutrients and herbicides.

The different constituents detected in the three sample 

media (water, fish tissue, and bed sediment) indicate that landuse activities both on and off post are influencing environmental conditions. Contaminants such as explosives that were 

sometimes detected in water samples have an obvious relation 

to military training; however, the occurrence and locations of 

some nutrients, insecticides, and trace elements suggest that 

land use both on and off post also could be influencing environmental conditions to some degree. 

Constituent concentrations at sites on Vache Grasse Creek, 

and particularly the most upstream site, which was located 

immediately downstream from an off-post wastewater-treatment facility, indicate that environmental conditions were being 

influenced by an off-post source. The most upstream site on 

Vache Grasse Creek had both the highest number of detections 

and the highest concentrations detected of all sites sampled. 

Event-mean storm concentrations and storm loads calculated 

from storm-flow samples at two sites each for Big and Vache 

Grasse Creeks indicate that storm loads were highest at the two 

Vache Grasse Creek sites for 24 of the 25 constituents detected. 

Further evaluation by normalizing storm loads at Big Creek to 

storm loads at Vache Grasse Creek by stream flow indicate that 

event loads at Vache Grasse Creek were about two or more 

times higher than those on Big Creek for 15 of the 25 constituents measured. Low concentrations of arsenic and lead were 

detected in water samples, but all detections for the two trace 

elements occurred in samples collected at the upstream site on 

Vache Grasse Creek. The nickel concentration in fish livers collected from the upstream site on Vache Grasse Creek was 45 

percent higher than the median of a national study of 145 sites. 

Mercury concentrations in edible fish tissue, which are a widespread concern in the United States, exceeded an USEPA criterion for methylmercury of 300 μg/kg in four of nine samples; 

however, concentrations are typical of mercury concentrations 

in fish tissues for the State of Arkansas.

Constituent concentrations at some sites indicate that environmental conditions are being influenced by on-post activities. 

Of the 55 (excluding total organic carbon) organic constituents 

analyzed in water samples, only 10 were detected above the 

minimum detection limit but four of those were explosives. 

Bed-sediment samples from one site located on Grayson Creek, 

and nearest the administrative and residential (cantonment) 

area, had detections for arsenic, copper, lead, manganese, 

nickel, and zinc that were above background concentrations, 

and concentrations for arsenic and nickel at this site exceeded 

lowest effect level criteria established by the U.S. Environmental Protection Agency. The site on Grayson Creek also had the 

only detections of DDT metabolites in bed sediment. 

Concentrations of some trace elements in all media sampled for this study could also have a relation to on-post activities 

or conditions. Some trace elements detected may result from the 

combined effects of sedimentation (a possible consequence of 

soil erosion resulting from training activities and an extensive 

road system) and trace element concentrations in soils in western Arkansas. Regarding sedimentation (and soil erosion), turbidity data collected at the most downstream site on Vache 

Grasse Creek, and observations of substantial sediment deposition in both Vache Grasse and Big Creeks indicate that turbidity 

and associated sedimentation is a chronic problem that is 

impairing the ecological integrity of Fort Chaffee streams. 

Trace element concentrations at some sites may be related to 

this chronic sedimentation and the associated redox potential of 

the aquatic environments sampled. 
2 Water Quality, Fish Tissue, and Bed Sediment Monitoring in Waterbodies of Fort Chaffee Maneuver Training Center,

Arkansas, 2002-2004

Introduction

The Fort Chaffee Maneuver Training Center (Fort Chaffee), a facility for the Arkansas Army National Guard (ANG) 

since 1997, covers approximately 65,000 acres and is located in 

western Arkansas just east of the city of Fort Smith (fig. 1) in 

the Arkansas River Valley and Ouachita Mountains physiographic provinces (Fenneman, 1938). A rich military history is 

associated with Fort Chaffee. Fort Chaffee was established in 

1941 under a Department of Army directive during World War 

II (WWII) and served as a training and housing facility for several U.S. Army armored and infantry divisions. From 1943 to 

1946, the facility was used to house about 3,000 German prisoners of war. Because many of the buildings constructed in the 

1940’s are still standing, Fort Chaffee also has served as the setting for two movies set in the WWII era. On two occasions, 

once in the 1970’s and once in the 1980’s, Fort Chaffee was 

used as a refugee camp. More recently, Fort Chaffee has served 

as a test site for the Joint Readiness Training Center and as a 

location for the U.S. Army Training and Doctrine Command. In 

addition to being used for training, much of Fort Chaffee is 

important to area sportsmen. The Fort Chaffee Wildlife Management Area offers hunting and fishing opportunities in western Arkansas (U.S. Department of Defense, 2000).

As many as 50,000 soldiers may undergo training at Fort 

Chaffee annually, and a large part of Fort Chaffee is used for 

some aspect of military training (U.S. Department of Defense, 

2000). Training activities include small arms firing (ranges), 

artillery ordnance, and equipment and personnel maneuvers. 

Because of the nature of ongoing training (lead and other metals 

contained in ammunition lodged in the landscape, explosive and 

phosphorus compounds associated with some ordnances, disruption of the landscape by exploding ordnances, associated 

pesticide use, and sedimentation from an extensive road system) and a poor understanding of environmental procedures 

during the WWII era, areas within Fort Chaffee have the potential to be sources of a large number of contaminants. Another 

concern is that because some streams flow on to Fort Chaffee, 

there is also the potential for sources that are off post to affect 

environmental conditions on post. To address these concerns, 

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

ANG, conducted a study to document concentrations from September 2002 to July 2004 for various chemical compounds in 

three media collected from waterbodies on Fort Chaffee—water, fish tissue, and bed sediment. This information is 

necessary before contaminant sources can be identified and 

managed in a manner that will minimize risk of future contamination and exposure. 

Purpose and Scope

The purpose of this report is to provide data from September 2002 to July 2004 for contaminants in the water, fish tissue, 

and bed sediment of Fort Chaffee’s streams and lakes. The three 

sampled media were analyzed for insecticides, polychlorinated 

binphenyls (PCBs), explosives, and trace elements. Additionally, water samples were analyzed for field parameters (water 

temperature, dissolved oxygen, specific conductance, and pH), 

total dissolved and suspended solids, fecal coliform bacteria, 

total organic carbon, nutrients, and herbicides, and bed sediments were analyzed for total organic carbon. Constituent concentrations detected in the three media and measured at the nine 

stream sites and four lake sites were compared to national and 

regional criteria, which can be used as a reference for the extent 

of contamination. One stream site was continuously monitored 

for three water-quality parameters—specific conductance, turbidity, and temperature. These continuous data were evaluated 

for relations to changes in streamflow conditions using stage as 

a surrogate for streamflow.

Description of Study Area

The area contained within Fort Chaffee is intermixed forest and grasslands (fig. 1). The ANG has implemented an extensive burning program in some areas where training is most 

intense (such as the training/ordnance-impact area) to control 

vegetation that can fuel wildfires started with ordnance explosions (Sabrina Kirkpatrick, Arkansas National Guard Natural 

and Cultural Resource Manager, oral commun., January 2004). 

As a result, much of Fort Chaffee is open grassland with sparse 

forest intermixed. Conversely, because livestock grazing is no 

longer a part of the land use, some areas that were once pasture 

and are not periodically burned are now in different stages of 

forest succession. Coalbeds have been documented in the 

Vache Grasse Creek drainage (Lamb, 1978), much of which is 

contained within Fort Chaffee, and mining scars in forested 

areas adjacent to the stream indicate that coal may have been 

mined there at one time.

Soils found in Fort Chaffee are the weathered remnants of 

the Hartshorn and McAlester Formations (Haley and others, 

1993), which are composed generally of clay, siltstone, and well 

indurated sandstone. In addition to bridges, an extensive road 

system also consists of low-water crossings for tanks and other 

artillery vehicles. Road use and maintenance, and a soil dominated by clay, results in a high potential for soil erosion and subsequent stream sediment deposition.

Acknowledgments

Thanks are extended to Amanda Riggs and Sabrina Kirkpatrick, Fort Chaffee Environmental Branch, who assisted the 

authors with locating sampling sites and with field sampling. 

Appreciation also is extended to U.S. Geological Survey 

(USGS) personnel Chris O’Dell, Bill Baldwin, and Brian Clark 

for assistance during round-the-clock sampling events. 
Methods 3

Methods

Chemical constituent data for this study were collected 

from September 2002 through July 2004. Water samples were 

collected at 13 sites—9 stream sites and 4 lake sites —and bed 

sediment samples were collected at 8 streams sites and 4 lake 

sites (table 1; fig. 1). Two of the larger streams, Big and Vache 

Grasse Creeks, were sampled at multiple sites. 

Fish tissue samples were collected at nine sites—the five 

stream sites with the largest drainage areas and the four lake 

sites. Field parameters (dissolved oxygen, pH, specific conductance, and water temperature) were measured on every sampling occasion (appendixes 1 and 2). One stream site was continuously monitored for three water-quality parameters— 

specific conductance, turbidity, and temperature—from 

November 2003 through July 2004. Continuous monitoring 

equipment was calibrated according to USGS protocols (Wagner and others, 2000).

All chemical analyses were performed by Severn Trent 

Laboratories (STL) in Arvada, Colorado, using laboratory 

methods and quality assurance/quality control (QA/QC) procedures approved by the U.S. Environmental Protection Agency 

(USEPA) (U.S. Environmental Protection Agency, 1983; 

1986a; 1986b). Laboratory QA/QC that are associated with 

USEPA methods include duplicate analysis, matrix spikes, 

method blanks, and surrogate analyses. For all three media, constituent concentrations that were between the minimum detection limit (MDL, the minimum concentration of a substance that 

can be measured and reported with 99 percent confidence that 

the concentration is greater than zero) and the reporting limit 

(RL, a value higher than the MDL and also the lowest level at 

which measurements become quantitatively meaningful) were 

estimated by the analytical laboratory and were reported as estimated values. Fecal coliform bacteria were identified and enumerated in the field by USGS following USGS procedures 

(Wilde and Ratke, 1998).

Table 1. Sampling site information for sites at Fort Chaffee, Arkansas, 2002 through 2004.

[FF, fish fillet; FL, fish liver; S, bed sediment; W, water]

Site name

Abbreviated name and

site identifier (fig. 1)

Station

identification

number Latitude1 Longitude1 Sample media

Big Creek tributary at Burnville Road Big Creek Site 1 (BC1) 07250673 35° 11’37" 94° 09’42" S, W

Big Creek at Potato Hill Road Big Creek Site 2 (BC2) 07250686 35° 15’40" 94° 06’29" FF, FL, S, W

Big Creek tributary at range 87 bypass Big Creek Site 3 (BC3) 07250688 35° 15’53" 94° 06’17" S, W

Big Creek at Bloomer Big Creek Site 4 (BC4) 07250700 35° 17’34" 94° 07’58" FF, FL, S, W

Christmas Knob Lake Christmas Knob Lake (CKL) 07250697 35° 17’18" 94° 09’40" FF, FL, S, W

Darby Lake Darby Lake (DL) 07253520 35° 15’51" 94° 01’45" FF, FL, S, W

Engineer Lake Engineer Lake (EL) 07250690 35° 16’45" 94° 06’59" FF, FL, S, W

Gin Creek near Washburn Gin Creek (GinC) 07258320 35° 10’26" 94° 04’23" S, W

Grayson Creek south of Highway 22 Grayson Creek (GRC) 07250573 35° 18’56" 94° 16’36" S, W

Mendenhall Swamp Lake Mendenhall Swamp Lake (MSL) 07250597 35° 17’43" 94° 15’10" FF, FL, S, W

Vache Grasse Creek near Greenwood Vache Grasse Creek Site 0 (VG0) 07250593 35° 14’11" 94° 14’03" FF, FL, W

Vache Grasse Creek near Howard Hill Vache Grasse Creek Site 1 (VG1) 07250595 35° 15’75" 94° 17’54" FF, FL, S, W

Vache Grasse Creek near Lavaca Vache Grasse Creek Site 2 (VG2) 07250600 35° 19’03" 94° 12’56" FF, FL, S, W

1

Latitude and longitude were obtained using North American Datum of 1927 (NAD 27).
01

01 2 

FORT CHAFFEE

MANEUVER TRAINING

CENTER

Fort

Smith

Barling

Greenwood

Charlesto

Lavaca

Arkansas

River

Vache

Grasse

Creek

Vache Grasse Creek

Big

Creek

Big

Creek

Gin

GRC

MSL

VG2

CKL

BC4

EL

BC3

BC2

GinC

BC1

VG0

VG1

VG1

CANTONMENT

AREA

Base from U.S. Geological Surveydigital data, 1:100,000

Christmas

Knob Lake

Engineer

Lake

Grayson

Creek

Mendenhall

Swamp Lake

Howard

Hill

Arkansas

STUDY

AREA

EXPLANATIONSAMPLING SITE AND SITE

IDENTIFIER (See Table 1)

FORT CHAFFEE MANEUVER

TRAINING CENTER BOUNDARY

AND FORT CHAFFEE WILDLIFE

MANAGEMENT AREA

RESIDENTIALINDUSTRIAL/COMMERCIALFORESTGRASS

LAND USESMALL ARMS IMPACT AREA ARTILLERY IMPACT AREA

94 20' o 94 10' o 94 15' o 94 05' o

35 20' o

35 15' o

35 10' o

!(10

!(10

!(22

!( !(60 60 !(22

!(96

£¤71

£¤71

!(96

Figure 1. Fort Chaffee boundaries and training ordnance-impact area and sampling sites.
Methods 5

Quality Assurance/Quality Control

Several steps were completed to ensure quality assurance 

of samples and the analyses. All sampling equipment was constructed of Teflon or Teflon-coated materials and was cleaned 

prior to sampling. The cleaning procedure for sampling equipment was as follows. All equipment first was rinsed with tap 

water. Sampling equipment used to collect samples for analysis 

of trace elements then was rinsed with a weak acid followed 

with a rinse of deionized water. Following the tap water rinse, 

sampling equipment used to collect samples for analysis of 

organic compounds was rinsed with methanol, followed by a 

rinse of deionized water. 

Once samples were collected, chain of custody and pertinent sample information forms were completed and copies were 

sent with all samples to the analytical laboratory. Three quality 

assurance/quality control (QA/QC) samples were collected. 

Duplicate samples were sent to the laboratory for one lake 

water-quality sample, one stream water-quality sample, and one 

bed-sediment sample for trace elements. Data for QA/QC samples are included with results for all other sample analyses.

Water Quality

Water-quality sampling methods varied depending on the 

type of waterbody being sampled and the flow condition during 

the sampling event. Stream sites that had a mean water velocity 

less than 1.5 feet per second (ft/s) were sampled using the grab 

method (Wilde and others, 1999). Grab samples were collected 

in the appropriate sample container just beneath the water surface; or if the sample required filtering, water was pumped 

directly from the stream through a filter and into a sample container. At streams where mean water velocity exceeded 1.5 ft/s, 

water samples were collected throughout the water column 

using the equal-width increment (EWI) method and composited 

(combined from several points in a stream cross section or from 

different lake sampling points) (Wilde and others, 1999). Composite samples from wadeable streams were collected using a 

depth-integrated sampler attached to a wading rod by the EWI 

method. When not wadeable, streams were sampled using the 

EWI method by lowering depth-integrating samplers into the 

stream from road bridges with a truck boom.

Lakes were sampled using protocols described by Wilde 

and others (1999). Water samples were collected from a boat by 

lowering a cylindrical bailer (a Teflon coated plastic tube (5.2 

cm × 0.9 m) with check valves at each end and having a capacity of about 1 liter, into the water column. Two liters of water 

collected at seven sampling points were composited for each 

lake sample. Where lake depth exceeded 1.8 m, 1 liter was collected at two depths (near 0.2 and 0.8 of total depth). Where the 

lake depth was less than 1.8 m, 2 liters were collected near mid 

depth.

Composite samples were processed in a different manner 

than grab samples. For the composite samples each subsample 

collected was composited into a 14-liter Teflon churn splitter. 

After all subsamples were collected, the sample was mixed 

thoroughly by churning to keep sediment suspended during processing of raw (unfiltered) samples. Sample containers for the 

unfiltered samples then were filled from a spigot, and sample 

containers for organic and dissolved constituents were filled 

with water pumped from the churn and through a filter. All 

composite samples were processed (split and filtered) in a 

mobile laboratory in the field. 

Standard shipping procedures were followed once samples 

were processed. Water samples were placed on ice and shipped 

to the analytical laboratory within 12 hours of sampling. Standard quality assurance and quality control procedures were 

completed for each shipment. 

Water-quality samples were collected during three flow 

conditions—base flow, stormflow, and event flow—to determine the relation between surface-water discharge and constituent concentrations. For this study, stormflow samples are distinguished from event-flow samples by the time lapse between 

the rain event and when sampling occurred. Event-flow samples 

were collected throughout the rise, peak, and fall of the 

hydrograph, while stormflow samples generally were collected 

several hours after the storm and subsequent to peak stormflow. 

All water samples were analyzed for the same constituents 

using the same analytical methods (table 2). One base-flow and 

stormflow sample were collected at all nine stream sites and all 

four lake sites.

Sampling procedures for event-flow sampling differed 

from sampling procedures for base-flow and stormflow sampling in other aspects. For the event-flow sampling effort, two 

sites each were sampled on Vache Grasse and Big Creeks (fig. 

1). For both streams, event-flow sampling sites were established where the streams flowed on and off of Fort Chaffee. All 

event-flow samples were collected during the same storm event. 

EWI water-quality samples were collected during the rise, peak, 

and fall of the storm-event hydrograph (for a total of three samples), at a frequency based on changes in stage (volume). 

Stream discharge was measured concurrent to water-quality 

sampling to compute total storm-discharge volume. Flowweighted aliquots of water-quality samples collected during the 

rise, peak, and fall were divided volumetrically and were composited to make one analytical sample. 

Composite sample results were used as an event-mean 

concentration (EMC) to compute the loads for the storm event. 

The estimated storm load for each constituent detected above 

the MDL was computed using the equation:

LOAD EMC AFV CF = × ×

Where LOAD is constituent load (in pounds) for the sampled 

storm,

EMC is event-mean concentration (in milligrams per 

liter) for the sampled storm,

AFV is accumulated flow volume (in cubic feet per 

second) for the sampled storm, and

CF is conversion factor (6.2382 × 10-5 if constituent 

concentration is reported in milligrams per liter or 

6.2382 × 10-8 if constituent concentration is 

reported in micrograms per liter).
6 Water Quality, Fish Tissue, and Bed Sediment Monitoring in Waterbodies of Fort Chaffee Maneuver Training Center,

Arkansas, 2002-2004

Table 2. Constituents analyzed in water samples collected at Fort Chaffee, Arkansas, 2002 through 2004.

[DDD, dichlorodiphenyldichloroethane; DDE, dichlorodiphenyldichloroethylene; DDT, dichlorodiphenyltrichloroethane; BHC; Benzene hexachloride; PETN, 

Pentaerythritoltetranitrate; HMX, Cyclotetramethylene tetranitramine; RDX, Cyclotrimethylene trinitramine; 2,4-D, 2,4 Dichlorophenoxy acetic acid; 2,4-DB, 

2,4-Dichlorophenoxybutyric acid; MCPA, 4-chloro-2-methylphenoxy acetic acid; MCPP, 2-methyl-4-chlorophenoxy propionic acid; 2,4,5-T , 2,4,5-Trichlorophenoxyacetic acid; 2,4,5-TP, 2,4,5-Trichlorophenoxypropionic acid; PCBs, polychlorinated biphenyls; HEM, hexane extractable material]

Biologic Explosives Other organic analytes

Fecal coliform indicator bacteria 4-Nitrotoluene Total Organic Carbon

PETN HEM (Oil and Grease)

Field parameters 4-Amino-2,6-dinitrotoluene

Dissolved oxygen 3-Nitrotoluene Nutrients

pH 2-Nitrotoluene Ammonia as nitrogen

Specific conductance 2-Amino-4,6-dinitrotoluene Ammonia plus organic nitrogen as nitrogen

Water temperature 2,6-Dinitrotoluene Nitrate plus nitrite as nitrogen

Turbidity 2,4-Dinitrotoluene Nitrite as nitrogen

HMX Orthophosphate as phosphorus

Organochlorine insecticides Nitrobenzene Total phosphorus as phosphorus

4,4’-DDD 1,3,5-Trinitrobenzene

4,4’-DDE Nitroglycerin Physical 

4,4’-DDT RDX Total dissolved solids

Aldrin 2,4,6-Trinitrotoluene Total suspended solids

alpha-BHC 1,3-Dinitrobenzene

alpha-Chlordane Tetryl Trace elements

beta-BHC Antimony

Chlordane (technical) Herbicides Arsenic

delta-BHC Dinoseb Barium

Dieldrin 2,4-DB Beryllium

Endosulfan I 2,4-D Cadmium

Endosulfan II Dalapon Chromium

Endosulfan sulfate Dicamba Cobalt

Endrin Dichlorprop Copper

Endrin aldehyde MCPA Lead

Endrin ketone MCPP Manganese

gamma-BHC (Lindane) 2,4,5-T Mercury

gamma-Chlordane 2,4,5-TP (Silvex) Molybdenum

Heptachlor Nickel

Heptachlor epoxide PCBs Selenium

Methoxychlor Aroclor 1242 Silver

Toxaphene Aroclor 1016 Thallium

Aroclor 1232 Zinc

Aroclor 1248

Aroclor 1254

Aroclor 1260

Aroclor 1221
Methods 7

As a further comparison of constituent loads in Big and 

Vache Grasse Creeks, event loads at a site on Big Creek were 

normalized by flow to the most upstream site on Vache Grasse 

Creek. This was done by dividing the flow during the sampled 

event at the site on Vache Grasse by the flow during the sampled event on Big Creek and then multiplying the quotient by 

the event load at the same Big Creek site. Streamflow was calculated during the sampling event by direct measurement or 

using a stage-discharge relation curve (Rantz and others, 1982). 

Fish Tissue

Fish tissue was collected and processed in the field according to protocols established by the USGS National Water-Quality Assessment Program (NAWQA) (Crawford and Luoma, 

1993). Fish sampling was conducted on four lakes in September 

2002 and at five stream sites in October 2002. Fish tissue was 

not sampled from Big Creek at sites 1 (BC1) and 3 (BC3) and 

from Gin and Grayson Creeks (fig. 1) because the streams were 

too small at the sampling sites to collect fish samples that were 

comparable (for size and species) to fish samples collected at 

other sites.

To reduce variability in the constituent dataset, individual 

fish targeted for tissue samples were of comparable size and of 

the same species. Composite samples of six largemouth or spotted bass or a combination of these two black bass species were 

targeted. Black bass were collected at seven of the nine sites, 

and at the two sites where black bass were not collected, golden 

redhorse were sampled at Big Creek Site 2 (BC2) and black 

crappie were sampled at Mendehall Swamp Lake (MSL). 

Processing of fish samples involved euthanizing each fish, 

collecting information pertaining to fish size, removing the 

appropriate fish tissue (sample), and preparing the sample for 

shipment to the analytical laboratory. The length and weight of 

each fish composited in a sample were recorded (table 3). Two 

types of tissue—fillet and liver—were removed and composited 

for separate analyses. Many contaminants are more concentrated in internal organs than fillets (Stober, 1991), and fillet 

samples were processed before liver samples to avoid contaminating the fillet. Fillets were collected by removing the left side 

of each fish on a plastic cutting board. Once the left side fillet 

had been removed from all fish collected for the composite sample, an incision was made through the stomach lining of each 

fish and the liver was removed. Both fillet and liver samples 

were stored in labeled glass jars and were immediately placed 

on dry ice. Fish tissue samples were shipped overnight to the 

laboratory.

Fish tissue samples were analyzed for numerous constituents (pesticides) that were historically associated with Fort 

Chaffee or other military bases (table 4). Liver samples were 

analyzed for trace elements to facilitate comparison to a large 

number of samples collected across the Nation by NAWQA. 

Fillet samples were analyzed for organic compounds and trace 

elements to indicate the risk associated with human consumption. 

Table 3. Characteristics of fish collected for tissue (fillet and liver) analysis at Fort Chaffee, Arkansas, 2002.

[--, weight not taken because of scale malfunction]

Big Creek Site 2 Golden redhorse (Moxostoma erythrurum)

Big Creek Site 4 Largemouth/Spotted bass (Micropterus spp.)

Christmas Knob Lake Largemouth bass (Micropterus salmoides)

Darby Lake Largemouth bass (Micropterus salmoides)

Engineer Lake Largemouth bass (Micropterus salmoides)

Mendenhall Swamp Lake Black crappie (Pomoxis nigromaculatus)

Vache Grasse Creek Site 0 Largemouth/Spotted bass (Micropterus spp.)

Vache Grasse Creek Site 1 Largemouth/Spotted bass (Micropterus spp.)

Vache Grasse Creek Site 2 Largemouth/Spotted bass (Micropterus spp.)

Site Fish species

Number

of

individuals

Mean

total

length

(millimeters)

Mean

weight

(grams)

4 258 223

5 274 249

6 258 272

6 283 266

6 295 300

6 243 260

5 258 --

6 260 247

5 304 384
Table 4. Constituents analyzed in bed sediment and fish tissue samples collected from lakes and streams at Fort Chaffee, Arkansas, 2002.

[PCBs, polychlorinated biphenyls; DDD, dichlorodiphenyldichloroethane; DDE, dichlorodiphenyldichloroethylene; DDT, dichlorodiphenyltrichloroethane; alpha-BHC, alpha-Hexachlorocyclohexane; delta-BHC; Benzene hexachloride; HMX, Cyclotetramethylene tetranitramine; PETN, Pentaerythritoltetranitrate; 

RDX, Cyclotrimethylene trinitramine]

1,3,5-Trinitrobenzene 4,4’-DDD Aroclor 1016 Antimony Total organic carbon

1,3-Dinitrobenzene 4,4’-DDE Aroclor 1221 Arsenic

2,4,6-Trinitrotoluene 4,4’-DDT Aroclor 1232 Beryllium

2,4-Dinitrotoluene Aldrin Aroclor 1248 Cadmium

2,6-Dinitrotoluene alpha-BHC Aroclor 1254 Chromium

2-Amino-4,6-dinitrotoluene alpha-Chlordane Aroclor 1260 Copper

2-Nitrotoluene beta-BHC Lead

3-Nitrotoluene Chlordane (technical) Mercury

4-Amino-2,6-dinitrotoluene delta-BHC Nickel

4-Nitrotoluene Dieldrin Selenium

HMX Endosulfan I Silver

PETN Endosulfan II Thallium

Nitrobenzene Endosulfan sulfate Zinc

Nitroglycerin Endrin

RDX Endrin aldehyde

Tetryl Endrin ketone

gamma-BHC (Lindane)

gamma-Chlordane

Heptachlor

Heptachlor epoxide

Methoxychlor

Toxaphene

8 Water Quality, Fish Tissue, and Bed Sediment Monitoring in Waterbodies of Fort Chaffee Maneuver Training Center,

Arkansas, 2002-2004

Organic Compounds

Explosives

Insecticides

and metabolites PCBs Trace elements1

1

Fish liver samples were analyzed only for trace elements.

Other2

2

Analyzed only in sediment samples.
Constituents Detected in Water, Fish Tissue, and Bed Sediment 9

Bed Sediment 

Fine-grain sediments in depositional areas naturally accumulate trace element and hydrophobic organic compounds 

(Shelton and Capel, 1994). To determine concentrations of 

these chemicals on Fort Chaffee, bed sediment was sampled at 

eight stream sites and four lake sites in late September 2002. 

Bed sediments were collected from multiple depositional areas 

in the sampling reaches using methods described in Shelton and 

Capel (1994). Wadeable streams were sampled using a teflon 

spoon or spatula to collect bed sediment, and bed sediments 

from nonwadeable streams and lakes were sampled using a grab 

sampler (petite Ponar) lowered from a boat. Regardless of the 

sampling method, bed sediment was collected from no more 

than 2 inches below the water/sediment interface. Composite 

sediment samples were mixed and then split into three sample 

components for analysis—trace elements, organic compounds, 

and total organic carbon (table 4). 

Continuous Monitoring

USGS established a monitoring station in late 2003 at 

Vache Grasse Creek at Highway 22 (Site 2) where the stream 

flows off of Fort Chaffee. USGS continuously monitored 

stream stage, water quality, and precipitation at this site (data 

are available in USGS National Water Information System at 

http://water.usgs.gov/nwis.station number 07250600). The 

streamflow gage records stream stage, which can then be related 

to measured discharge to establish a rating curve that can be 

used to estimate discharge at various stream stages (Rantz and 

others, 1982). Knowing discharge, or the volume of water that 

flows past a gaging station in a given time, can be beneficial 

because these data facilitate the computation of constituent 

loads for a given time.

The primary purpose for continuously monitoring water 

quality at this site was to investigate long-term relations 

between turbidity and stream stage (stream stage is a surrogate 

for discharge; increasing stage generally indicates increasing 

discharge). However, because specific conductance can be 

indicative of the presence of contaminants, monitoring this 

parameter also could be beneficial to ANG. Continuous waterquality monitoring equipment was calibrated according to 

USGS protocols (Wagner and others, 2000).

Constituents Detected in Water, Fish Tissue, 

and Bed Sediment

Water Quality

Of the 55 organic compounds analyzed in 36 water samples, only 10 compounds had concentrations above the MDL 

and none were above the RL on any occasion (table 5). Four 

explosive constituents were detected, resulting in explosives 

being the most frequently detected of the four types of organic 

compounds (explosives, herbicides, oil and grease, and organochlorine insecticides and metabolites). Although there was 

only one oil and grease constituent (hexane extractable material 

or HEM), it was detected the most frequently of all organic constituents (in 32 of 36 samples), but never above the RL. 

Water samples were analyzed for 17 trace elements, but 

only 7 trace elements—arsenic, barium, copper, lead, manganese, nickel, and zinc—were detected at concentrations higher 

than the RL (table 6). Five of those seven trace elements—

arsenic, copper, lead, nickel, and zinc—are considered to be priority pollutants and aquatic life criteria have been established 

(U.S. Environmental Protection Agency, 2002; table 6). None 

of the five priority pollutants were detected above the aquatic 

life criteria. All detections above the RL for arsenic and lead 

occurred in stormflow and event flow samples at Vache Grasse 

Creek Site 0, the upstream site on Vache Grasse Creek, which 

is located immediately downstream from an off-post wastewater-treatment facility. Five of the seven detections for both 

nickel and zinc above the RL also were from sites located on 

Vache Grasse Creek. Detections above the RL for copper were 

more common in the Big Creek drainage than in the Vache 

Grasse Creek drainage (six of seven detections). The estimated 

concentration of cadmium (above MDL but below RL) in a 

stormflow sample from Big Creek Site 2 was above the aquatic 

life criterion (table 6). 

Manganese and barium are not considered to be priority 

pollutants by the USEPA but were detected above the RL for 

every water sample collected. USEPA is in the process of developing new aquatic life criteria for manganese (U.S. Environmental Protection Agency, 2004) but earlier USEPA publications suggest that manganese can be toxic to some freshwater 

aquatic life at 1,500 μg/L (U.S. Environmental Protection 

Agency, 1979). The manganese concentration in one sample at 

Mendenhall Swamp Lake had a concentration of 2,000 μg/L, 

and manganese concentrations were higher in lake samples than 

in stream samples. Drinking water regulations proposed by the 

USEPA recommend a concentration of 200 μg/L be used as a 

drinking water standard for manganese (U.S. Environmental 

Protection Agency, 1993), and the United Nations Food and 

Agricultural Organization also uses 200 μg/L as a recommended maximum concentration in irrigation water (Pais and 

Jones, 1997). Nine of 36 water samples exceeded 200 μg/L. A 

previous USGS study (Lamb, 1978), conducted in the headwaters of Vache Grasse Creek, also noted that concentrations of 

manganese were relatively high (greater than 1,000 μg/L). One 

possible explanation for elevated manganese concentrations is 

that background concentrations seem to be higher in western 

Arkansas than for most other regions (Gustavsson and others, 

2001). Another possible explanation for elevated manganese 

concentrations, particularly for stream samples, is related to the 

redox potential of the aquatic environments sampled. Accumulated bed sediments and organic material in the bottom substrate 

may result in a high biochemical oxygen demand and a reducing 

environment for several of the waterbodies sampled, 
Table 5. Concentrations of organic compounds detected in water samples collected at Fort Chaffee, Arkansas, 2002 through 2004.

[Concentrations in micrograms per liter; E, explosive; H, herbicide; OI, organochlorine insecticide; OG, oil and grease; --, not detected; e, value is between the minimum detection 

is an estimated value; delta-BHC; Benzene hexachloride; HEM, Hexane extractable material; MCPA, 4-chloro-2-methylphenoxy acetic acid; RDX, Cyclotrimethylene trinitrami

tion; 2,4-D, 2,4-Dinitrotoluene]

Vache Grasse Creek Site 2 Base flow 9/04/2003Vache Grasse Creek Site 2 Stormflow 1/18/2004Minimum detection limit2 0.013/0.023 0.03/0.039 0.012/0.1 0.012/ 0.024 0.16/0.24 0.081/0.23 12/37 0.83/1 0.005/0.01 Reporting limit 

Sampling site Sample type Date sampled 1,3-Dinitrobenzene Nitroglycerin RDX Tetryl 2,4-D Dicamba MCPA HEM delta-BHC 

E E E E H H H OG OI 

Big Creek Site 1 Base flow 9/18/2002 -- -- -- -- -- -- -- 1.1e -- Big Creek Site 1 Stormflow 3/19/2003 -- -- -- -- -- -- -- 3.2e -- Big Creek Site 1 Event (EMC) 5/16/2003 -- -- -- -- -- -- -- 4.4e -- Big Creek Site 2 Base flow 9/17/2002 -- -- -- -- -- -- -- 2.2e -- Big Creek Site 2 Stormflow 3/19/2003 -- -- -- -- -- -- -- 3.2e -- Big Creek Site 3 Base flow 9/17/2002 -- -- 0.50e -- -- -- -- 3.1e -- Big Creek Site 3 Stormflow 3/19/2003 -- -- -- -- -- -- -- 2.2e -- Big Creek Site 4 Base flow 9/17/2002 -- -- -- -- -- -- -- 2.6e -- Big Creek Site 4 Stormflow 3/19/2003 -- -- -- -- -- -- -- 2.6e -- Big Creek Site 4 Event (EMC) 5/17/2003 -- -- -- -- -- -- -- 4.1e -- Big Creek Site 4 Base flow 9/04/2003 -- -- -- -- -- -- -- 2.7e -- Big Creek Site 4 Stormflow 1/18/2004 -- -- 0.06e -- -- -- -- 1.5e -- Christmas Knob Lake Base flow 9/24/2002 -- -- -- -- 0.71e -- -- 1.1e -- Christmas Knob Lake Base flow1

1Duplicate sample.

9/24/2002 -- -- -- -- 0.46e -- -- 2.2e -- 

Christmas Knob Lake Stormflow 12/30/2003 -- -- -- -- -- -- -- -- -- Darby Lake Base flow 9/23/2002 -- -- -- -- 1.2e -- -- 0.9e 0.034e Darby Lake Stormflow 12/29/2003 0.015e -- -- -- -- -- -- -- -- Engineer Lake Base flow 9/24/2002 -- -- -- -- 0.48e -- -- 2.0e -- Engineer Lake Stormflow 12/29/2003 -- -- -- -- -- -- -- -- -- Gin Creek Base flow 9/18/2002 -- -- -- -- -- -- -- 1.7e -- Gin Creek Stormflow 3/20/2003 -- -- -- -- -- -- 42e 1.8e -- Grayson Creek Base flow 9/17/2002 -- -- -- -- -- -- -- 2.2e -- Grayson Creek Stormflow 3/20/2003 -- -- -- -- -- -- -- 2.5e -- Mendenhall Swamp Lake Base flow 9/24/2002 -- 0.087e -- -- 1.7e -- -- 1.1e -- Mendenhall Swamp Lake Stormflow 12/30/2003 -- -- -- -- -- -- -- 1.2e -- Vache Grasse Creek Site 0 Base flow 11/5/2002 -- 0.048e -- -- -- -- -- 0.84e -- Vache Grasse Creek Site 0 Stormflow 5/16/2003 -- -- -- -- 0.50e 0.099e -- 4.1e -- Vache Grasse Creek Site 0 Event (EMC) 5/17/2003 -- -- -- 0.013e 0.91e -- -- 4.8e -- Vache Grasse Creek Site 0 Base flow 9/04/2003 -- -- -- -- -- -- -- 3.6e -- Vache Grasse Creek Site 0 Stormflow 1/18/2004 -- -- -- -- -- -- -- 2.2e -- Vache Grasse Creek Site 1 Base flow 9/18/2002 -- -- -- -- -- -- -- 1.7e -- Vache Grasse Creek Site 2 Base flow 9/16/2002 -- 0.087e -- -- -- -- -- -- -- Vache Grasse Creek Site 2 Stormflow 5/17/2003 -- -- -- -- -- -- -- 4.1e -- Vache Grasse Creek Site 2 Event (EMC) 5/18/2003 -- -- -- -- -- -- -- 3.9e -- 

-- -- -- -- -- -- -- 2.4e -- -- -- -- -- -- -- -- 1.2e -- 

2Analytical laboratory reported two minimum detection limits and reporting limits for some constituents.

0.12 0.12 0.12/0.6 0.12 4.00 2.00 400 5.0 0.05 
Table 6. Trace element concentrations for water samples collected at Fort Chaffee, Arkansas, 2002 through 2004.[Concentrations are in micrograms per liter; e, value is between the minimum detection limit and the laboratory reporting limit and is an estimated value; bold, values are above --, not detected; median values were calculated using estimated values as absolute numbers; n/a, constituent not detected for specified event; EMC, Event mean concentration]

Sampling site Sample type Date sampled Antimony Arsenic Barium Beryllium Cadmium Chromium Cobalt 

Big Creek Site 1 Base flow 9/18/2002 -- 0.52e 34 -- -- 0.34e 0.18e 

Big Creek Site 1 Stormflow 3/19/2003 0.53e 0.57e 20 0.042e 0.034e 1.5e 0.37e 

Big Creek Site 1 Event (EMC) 5/16/2003 0.20e 0.37e 25 -- 0.14e 0.74e 0.24e 

Big Creek Site 2 Base flow 9/17/2002 0.22e 0.48e 16 -- -- 0.40e 0.10e 

Big Creek Site 2 Stormflow 3/19/2003 -- 0.20e 11 0.028e 0.35e 1.1e 0.13e 

Big Creek Site 3 Base flow 9/17/2002 0.09e 0.39e 15 -- -- 0.39e 0.077e 

Big Creek Site 3 Stormflow 3/19/2003 0.042e 0.24e 12 0.036e 0.19e 1.2e 0.18e 

Big Creek Site 4 Base flow 9/17/2002 0.055e 1.1e 23 -- -- 0.39e 0.45e 

Big Creek Site 4 Stormflow 3/19/2003 0.071e 0.18e 9.8 -- 0.077e 1.1e 0.25e 

Big Creek Site 4 Event (EMC) 5/17/2003 0.27e 0.48e 15 -- -- 0.54e 0.16e 

Big Creek Site 4 Base flow 9/04/2003 0.064e 1.3e 27 -- -- 0.57e 0.63e 

Big Creek Site 4 Stormflow 1/18/2004 0.18e 0.22e 11 -- -- 0.59e 0.15e 

Christmas Knob Lake Base flow 9/24/2002 0.042e 0.97e 2.5 -- -- 0.59e 0.26e 

Christmas Knob Lake Base flow1 9/24/2002 -- 0.94e 3.6 -- -- 0.45e 0.23e 

Christmas Knob Lake Stormflow 12/30/2003 0.067e 0.48e 19 -- -- 0.59e 0.13e 

Darby Lake Base flow 9/23/2002 -- 0.44e 7.6 -- -- 0.41e 0.093e 

Darby Lake Stormflow 12/29/2003 -- 0.39e 17 -- -- 0.68e 0.072e 

Engineer Lake Base flow 9/24/2002 -- 0.06e 1.8 -- -- 0.47e 0.048e 

Engineer Lake Stormflow 12/29/2003 0.33e 0.45e 8.4 -- -- 0.67e 0.06e 

Gin Creek Base flow 9/18/2002 -- 2.4e 46 -- -- 0.46e 0.51e 

Gin Creek Stormflow 3/20/2003 0.076e 0.22e 14 -- 0.055e 1.2e 0.12e 

Grayson Creek Base flow 9/17/2002 0.085e 0.5e 25 -- -- -- 0.14e 

Grayson Creek Stormflow 3/20/2003 0.27e 0.33e 17 -- 0.091e 1.1e 0.20e 

Mendenhall Swamp Lake Base flow 9/24/2002 1.3e 0.64e 12 -- -- 0.26e 0.71e 

Mendenhall Swamp Lake Stormflow 12/30/2003 0.082e 0.3e 3.8 -- -- 0.65e 0.098e 
Vache Grasse Creek Site 0 Base flow 11/05/2002 0.099e 1.9e 28 -- 0.03e 0.61e 0.36e 

Vache Grasse Creek Site 0 Stormflow 5/16/2003 0.73e 15 31 -- -- 0.61e 0.62e Vache Grasse Creek Site 0 Event (EMC) 5/17/2003 0.28e 6 29 -- -- 0.67e 0.58e 

Vache Grasse Creek Site 0 Base flow 9/04/2003 0.60e 1.9e 27 -- 0.074e 0.54e 0.69e 

Vache Grasse Creek Site 0 Stormflow 1/18/2004 -- 0.43e 22 -- -- 0.68e 0.31e 

Vache Grasse Creek Site 1 Base flow 9/18/2002 -- 0.63e 39 -- -- 0.39e 0.21e 

Vache Grasse Creek Site 2 Base flow 9/16/2002 1.4e 1e 33 -- -- 0.55e 0.17e 

Vache Grasse Creek Site 2 Stormflow 5/17/2003 0.18e 0.72e 31 -- -- 0.49e 0.5e 

Vache Grasse Creek Site 2 Event (EMC) 5/18/2003 0.16e 0.63e 28 -- 0.061e 0.43e 0.35e 

Vache Grasse Creek Site 2 Base flow 9/04/2003 -- 1.4e 43 -- -- 0.69e 0.54e 

Vache Grasse Creek Site 2 Stormflow 1/18/2004 0.072e 0.49e 19 -- -- 0.61e 0.24e 

Base flow median 0.09 0.97 25 n/a 0.05 0.46 0.23 Event and stormflow median 0.18 0.43 17 0.04 0.08 0.67 0.20 Median for all flows 0.17 0.51 19 0.04 0.08 0.59 0.22 Aquatic life criteria -- 150 -- -- 0.25 11 

Reference fresh water2 0.20 0.50 10.00 0.10 0.20 1.0 0.50 

Minimum detection limit3 0.024, 0.04 0.061, 0.12 0.057, 0.081 0.028, 0.032 0.022, 0.051 0.13, 0.24 0.015, 0.0

Reporting limit 2.0 5.0 1.0 1.0 1.0 2.0 1.0 

Table 6. Trace element concentrations for water samples collected at Fort Chaffee, Arkansas, 2002 through 2004.—Continued[Concentrations are in micrograms per liter; e, value is between the minimum detection limit and the laboratory reporting limit and is an estimated value; bold, values are above 

--, not detected; median values were calculated using estimated values as absolute numbers; n/a, constituent not detected for specified event; EMC, Event mean concentration]

Sampling site Sample type Date sampled Antimony Arsenic Barium Beryllium Cadmium Chromium Cobalt 
Table 6. Trace element concentrations for water samples collected at Fort Chaffee, Arkansas, 2002 through 2004.--Continued[Concentrations are in micrograms per liter; e, value is between the minimum detection limit and the laboratory reporting limit and is an estimated value; bold, values are above --, not detected; median values were calculated using estimated values as absolute numbers; n/a, constituent not detected for specified event; EMC, Event mean concentration]

Sampling site Sample type Date sampled Manganese Mercury Molybdenum Nickel Selenium Silver Thallium 

Big Creek Site 1 Base flow 9/18/2002 17 -- 0.15e 1.5e 0.53e -- -- 

Big Creek Site 1 Stormflow 3/19/2003 43 -- 0.26e 2.4 -- 0.035e -- Big Creek Site 1 Event (EMC) 5/16/2003 10 0.029e 0.096e 2.5 -- -- -- Big Creek Site 2 Base flow 9/17/2002 52 -- 0.21e 0.94e 0.35e -- -- 

Big Creek Site 2 Stormflow 3/19/2003 14 -- 0.032e 1.1e -- 0.014e -- 

Big Creek Site 3 Base flow 9/17/2002 13 -- 0.11e 0.79e 0.50e -- -- 

Big Creek Site 3 Stormflow 3/19/2003 22 -- -- 1.1e -- 0.022e -- 

Big Creek Site 4 Base flow 9/17/2002 430 -- 0.14e 1.2e 0.31e -- -- 

Big Creek Site 4 Stormflow 3/19/2003 45 -- 0.062e 1.2e -- 0.013e -- 

Big Creek Site 4 Event (EMC) 5/017/2003 54 0.017e 0.15e 1.1e -- -- -- Big Creek Site 4 Base flow 9/04/2003 950 -- 0.19e 1.3e -- -- -- 

Big Creek Site 4 Stormflow 1/18/2004 24 -- 0.16e 0.88e -- -- -- 

Christmas Knob Lake Base flow 9/24/2002 1,000 -- 0.20e 0.83e 0.63e -- -- 

Christmas Knob Lake Base flow1 9/24/2002 950 -- 0.054e 1.0e 0.46e -- -- 

Christmas Knob Lake Stormflow 12/30/2003 70 -- 0.046e 1.2e -- -- -- 

Darby Lake Base flow 9/23/2002 6.7 -- -- 0.35e -- -- -- 

Darby Lake Stormflow 12/29/2003 34 -- 0.083e 0.37e -- -- -- 

Engineer Lake Base flow 9/24/2002 140 -- 0.085e 0.47e 0.31e -- -- 

Engineer Lake Stormflow 12/29/2003 33 -- 0.17e 0.36e -- -- -- 

Gin Creek Base flow 9/18/2002 270 -- 0.13e 1.7e 0.51e -- -- 

Gin Creek Stormflow 3/20/2003 16 -- 0.037e 0.93e -- 0.016e -- 

Grayson Creek Base flow 9/17/2002 59 -- 0.14e 1.2e 0.36e -- -- 

Grayson Creek Stormflow 3/20/2003 34 -- 0.12e 1.6e -- 0.038e -- 

Mendenhall Swamp Lake Base flow 9/24/2002 2,000 -- 1.3e 0.32e 0.23e 0.13e 0.054e 

Mendenhall Swamp Lake Stormflow 12/30/2003 72 -- 0.056e 0.38e -- -- -- 
Vache Grasse Creek Site 0 Base flow 11/05/2002 120 -- 0.24e 1.5e 0.32e 0.071e -- Vache Grasse Creek Site 0 Stormflow 5/16/2003 260 0.026e 0.58e 2.3 -- -- -- 

Vache Grasse Creek Site 0 Event (EMC) 5/17/2003 150 0.032e 0.49e 2.6 0.24e -- -- 

Vache Grasse Creek Site 0 Base flow 9/04/2003 50 -- 0.76e 3.4 -- -- -- Vache Grasse Creek Site 0 Stormflow 1/18/2004 140 -- 0.18e 1.5e -- -- -- 

Vache Grasse Creek Site 1 Base flow 9/18/2002 99 -- 0.32e 2.1 0.47e -- -- 

Vache Grasse Creek Site 2 Base flow 9/16/2002 150 -- 1.4e 1.9e 0.71e -- 0.029e 

Vache Grasse Creek Site 2 Stormflow 5/17/2003 380 0.042e 0.31e 1.8e -- -- -- 

Vache Grasse Creek Site 2 Event (EMC) 5/18/2003 180 0.038e 0.27e 1.8e -- -- -- 

Vache Grasse Creek Site 2 Base flow 9/04/2003 630 -- 0.53e 2.3 -- -- -- 

Vache Grasse Creek Site 2 Stormflow 1/18/2004 64 -- 0.20e 1.4e -- -- -- 

Base flow median 140 n/a 0.20 1.2 0.46 0.13 0.04 Event- and stormflow median 45 0.03 0.16 1.2 0.24 0.02 n/a Median for all flows 67 0.03 0.17 1.2 0.41 0.04 0.04 Aquatic life criteria2 0.77 52 5.0 

Reference fresh water 3 5.0 0.10 1.0 0.30 0.20 0.30 0.04 

Minimum detection limit4 0.061, 0.10 0.015, 0.028 0.023, 0.04 0.15, 0.25 0.19, 0.24 0.012, 0.058 0.012, 0.015 

Reporting limit 1.0 2.0 2.0 2.0 5.0 5.0 1.0 

1Duplicate sample.2U.S. Environmental Protection Agency, 2002.3Pais and Jones, 1997.4Analytical laboratory reported two minimum detection limits for some constituents.

Table 6. Trace element concentrations for water samples collected at Fort Chaffee, Arkansas, 2002 through 2004.--Continued[Concentrations are in micrograms per liter; e, value is between the minimum detection limit and the laboratory reporting limit and is an estimated value; bold, values are above 

--, not detected; median values were calculated using estimated values as absolute numbers; n/a, constituent not detected for specified event; EMC, Event mean concentration]

Sampling site Sample type Date sampled Manganese Mercury Molybdenum Nickel Selenium Silver Thallium 
Constituents Detected in Water, Fish Tissue, and Bed Sediment 15

particularly where large amounts of sediments have been deposited. Trace elements such as manganese can occur in water in 

high concentrations in this situation because under reduced conditions, manganese solubility (the ability to mix with water) can 

increase (Mitsch and Gosselink, 1993).

A reducing environment also could partially explain consistent detections of barium in waterbodies at Fort Chaffee. Low 

concentrations of barium were detected in all 36 water samples. 

Barium will sometimes dissolve from barium sulfate (BaSO4) 

under low sulfate, anaerobic conditions common to stagnant 

waterbodies that are cutoff from other surface and ground 

waters (U.S. Environmental Protection Agency, 1997). Observations indicate that this situation persists for some small 

streams on Fort Chaffee during base-flow periods and this could 

explain why barium concentrations consistently were higher for 

base-flow samples than for stormflow or event samples. Phosphate fertilizers, which can contain as much as 200 mg/L of barium (Pais and Jones, 1997), and explosives also are potential 

sources of barium.

Nutrient concentrations in water samples generally were 

below the RL at most sites; however, nutrient concentrations 

generally were higher at sites located on Vache Grasse Creek 

than at other sampling sites (table 7). Of the three sites on Vache 

Grasse Creek, nutrient concentrations were highest at Vache 

Grasse Creek Site 0. Higher nutrient concentrations at this site 

could indicate released or overflowing effluent from an off-post 

wastewater-treatment facility, which would provide some 

explanation for why total phosphorus concentrations were 

higher in base-flow samples than in stormflow samples (table 

7). 

Nutrient concentrations in waterbodies sampled at Fort 

Chaffee were compared to data collected at 14 sites sampled by 

NAWQA in the Ozark Plateaus from 1993 to 1995 (Davis and 

Bell, 1998). Median maximum values for the NAWQA data 

were compared to median values for base-flow, event-flow, and 

stormflow sampling events (table 7). Median values for the sites 

sampled at Fort Chaffee exceeded the median maximum value 

for the 14 sites sampled in the Ozark Plateaus for three of six 

nutrient constituents: dissolved ammonia, total ammonia plus 

organic nitrogen, and total phosphorus. 

Total dissolved solids concentrations varied more by 

waterbody than by sampling date or the amount of flow associated with the sampling event (table 7). Highest concentrations 

consistently occurred at Vache Grasse Creek Site 0, followed by 

Vache Grasse Creek Site 2, and sites on Big Creek. The median 

value for all dissolved solids concentrations measured in this 

study (87 milligrams per liter (mg/L)) was slightly higher than 

typical values for the Arkansas River Valley physiographic 

region (50-75 mg/L; Petersen, 1988). In contrast to total dissolved solids concentrations, the highest total suspended solids 

concentrations occurred at sites located on Big Creek and for 

samples collected during event-flow or stormflow events. 

Fecal coliform bacteria concentrations were higher in samples from streams than from lakes, and were higher for stormflow and event-flow compared to base-flow samples (table 7). 

Concentrations ranged from less than 1 colony/100 milliliter 

(col/100 mL) to 18,400 col/100 mL. Arkansas standards for primary contact state that the 30-day geometric mean values 

should not exceed 200 col/100 mL, from April through September (Arkansas Department of Environmental Quality, 2004). 

Eleven of 15 stormflow samples exceeded this criterion 

(although the sample results for this report do not represent a 

30-day geometric mean); however, the median value for all 

fecal coliform concentrations measured in this study (78 col/

100 mL) was typical for the Arkansas River Valley physiographic region (20-100 col/100 mL; Petersen, 1988). Dense 

wildlife populations in the Fort Chaffee Wildlife Management 

Area may account for elevated bacteria concentrations.

Event-mean storm concentrations calculated from samples 

collected at two sites each on Big and Vache Grasse Creeks 

indicate that most constituents occurred at higher concentrations in Vache Grasse Creek than in Big Creek for the storm 

sampled in May 2003 (table 8). Of the 25 detected constituents, 

20 were highest at one of the two sites on Vache Grasse Creek 

and of those, 18 were highest at Vache Grasse Creek Site 0, the 

site immediately downstream from an off-post wastewatertreatment facility.

Event loads calculated from event-mean concentrations 

also indicate that water-quality contamination is greater at 

Vache Grasse Creek than at Big Creek. Event loads were highest at the two Vache Grasse Creek sites for 24 of the 25 constituents detected (table 9). Higher event loads at Vache Grasse 

Creek could be partially explained by higher streamflows at the 

Vache Creek sites compared to the Big Creek sites during the 

sampled event (table 8). However, further evaluation by normalizing event loads at Big Creek Site 4 (the most downstream 

site on Big Creek) to event loads at Vache Grasse Creek Site 0 

(the most upstream site on Vache Grasse Creek) by streamflow 

indicates that event loads at Vache Grasse Creek Site 0 were 

about two or more times higher than the loads at Big Creek Site 

4 for 15 of the 25 constituents measured (table 10). Constituent 

loads that were five or more times higher at Vache Grasse 0 than 

at the two sites on Big Creek included nitrite plus nitrate as N, 

nitrite as N, total ammonia plus organic nitrogen as N, total 

phosphorus, arsenic, and total suspended solids.

Daily mean values measured for stage, temperature, specific conductance, and turbidity at Vache Grasse Creek Site 2 

(appendixes 3-6) reveal the relations between the water-quality 

constituents measured and stream stage. Stream stage, specific 

conductance, and turbidity are compared for the month of April 

2004 to illustrate these relations (fig. 2). In general, there is a 

pronounced parallel relation between stage and turbidity. Conversely, there is a less pronounced inverse relation between 

stage and specific conductance. Continuous data collected thus 

far indicate that turbidity and specific conductance have potential as surrogates that can be used to monitor the possible presence of contaminants in surface-water runoff. 
Table 7. Nutrient and other selected constituents detected in water samples collected at Fort Chaffee, Arkansas, 2002 through 2004. [e, value is between the minimum detection limit and the reporting limit and is an estimated value; --, constituent not detected for specified event; n/a, not applicable; bold, indiced the median maximum of 14 sites sampled in the Ozark Plateaus, mg/L, milligrams per liter; col./100 mL, colonies per 100 milliliters; NAWQA, National Water-Quality Assemean concentration]

Sampling site

Sampling

type

Data

sampled

Ammonia

as N

(mg/L)

Nitrite plus

nitrate as N

(mg/L)

Nitrite

as N

(mg/L)

Total ammonia

plus organic

nitrogen as N

(mg/L)

Orthophosphorus

as P

(mg/L)

Total

phosphorus

(mg/L)

Total

dissolv

solids

(mg/L

Big Creek Site 1 Base flow 9/18/2002 0.022e 0.019e 0.0039e 0.36e -- 0.071 85 Big Creek Site 1 Stormflow 3/19/2003 0.098e 0.24 0.011 0.37e 0.063 0.21 110 Big Creek Site 1 Event (EMC) 5/16/2003 -- 0.41 0.014 0.33e -- 0.053 110 Big Creek Site 2 Base flow 9/17/2002 0.039e 0.025e -- -- -- 0.036e 57 Big Creek Site 2 Stormflow 3/19/2003 0.076e 0.014e 0.0075e 0.60 0.036e 0.019e 81 Big Creek Site 3 Base flow 9/17/2002 0.042e -- -- -- -- 0.10 110 Big Creek Site 3 Stormflow 3/19/2003 0.048e 0.031e 0.013 0.62 0.042e 0.14 130 Big Creek Site 4 Base flow 9/17/2002 0.04e -- -- -- -- 0.10 62 Big Creek Site 4 Stormflow 3/19/2003 0.066e 0.029e 0.01 0.49e 0.05 0.078 97 Big Creek Site 4 Event (EMC) 5/17/2003 0.073e 0.087e 0.0075e 0.34e -- 0.038e 77 Big Creek Site 4 Base flow 9/04/2003 0.068e -- 0.0048e 0.4e -- 0.027e 69 Big Creek Site 4 Stormflow 1/18/2004 -- 0.15 -- 0.57 -- 0.033e 88 Christmas Knob Lake Base flow 9/24/2002 0.16 -- 0.0028e 0.63 -- 0.51 36 Christmas Knob Lake Base flow1 9/24/2002 0.16 -- 0.0028e 0.69 -- 0.12 46 

Christmas Knob Lake Stormflow 12/30/2003 0.19 0.24 0.0053e 1.1 -- 0.019e 39 Darby Lake Base flow 9/23/2002 -- 0.041e 0.0035e 0.22e -- 0.02e 24 Darby Lake Stormflow 12/29/2003 -- 0.11 0.0048e 0.61 -- -- 48 Engineer Lake Base flow 9/24/2002 0.06e 0.029e 0.003e 0.16e -- 0.12 21 Engineer Lake Stormflow 12/29/2003 0.038e 0.046e 0.0031e 0.47e -- -- 40 Gin Creek Base flow 9/18/2002 0.067e 0.23 0.011 0.14e -- 0.26 110 Gin Creek Stormflow 3/20/2003 0.082e -- 0.0044e 0.29e 0.032e -- 71 Grayson Creek Base flow 9/17/2002 0.043e 0.014e -- -- -- 0.038e 89 Grayson Creek Stormflow 3/20/2003 0.069e 0.047e 0.0088e 0.56 0.034e 0.021e 100 Mendenhall Swamp Lake Base flow 9/24/2002 0.072e -- 0.0028e 0.44e -- 0.11 54 Mendenhall Swamp Lake Stormflow 12/30/2003 -- -- 0.0036e 1.1 -- 0.044e 48 Vache Grasse Creek Site 0 Base flow 11/5/2002 0.087e 2.0 0.11 0.62 0.31 -- 160 Vache Grasse Creek Site 0 Stormflow 5/16/2003 0.29 1.3 0.073 0.62 0.15 0.30 160 Vache Grasse Creek Site 0 Event (EMC) 5/17/2003 0.36 1.7 0.08 0.73 0.27 0.25 170 Vache Grasse Creek Site 0 Base flow 9/04/2003 -- 4.3 0.031 0.59 0.74 0.83 240 
Vache Grasse Creek Site 0 Stormflow 1/18/2004 0.051e 0.66 0.004e 0.58 0.029e 0.12 140 Vache Grasse Creek Site 1 Base flow 9/18/2002 -- -- 0.0029e -- -- 0.061 160 Vache Grasse Creek Site 2 Base flow 9/16/2002 0.10 0.023e 0.003e -- -- 0.56 84 Vache Grasse Creek Site 2 Stormflow 5/17/2003 0.22 0.23 0.026 0.40e 0.018e 0.056 150 Vache Grasse Creek Site 2 Event (EMC) 5/18/2003 0.17 0.37 0.024 0.32e 0.02e 0.068 160 Vache Grasse Creek Site 2 Base flow 9/04/2003 0.066e 0.022e 0.0052e 0.44e -- 0.041e 150 Vache Grasse Creek Site 2 Stormflow 1/18/2004 0.042e 0.52 0.0025e 0.85 -- 0.10 130 Base-flow median2 0.060 0.019 0.004 0.220 0.000 0.100 69 

Event and stormflow median2 0.069 0.150 0.008 0.570 0.020 0.053 100 

Median2 for all flows 0.066 0.036 0.005 0.440 0.000 0.065 87 

Ozark NAWQA median(maximum at 14 sites)

0.020 3.1 n/a < 0.20 0.070 0.080 n/a 

Ozark NAWQA 90th percentile(maximum at 14 sites)

0.060 4.7 n/a 0.500 0.590 0.600 n/a 

Minimum detection limit3 0.013/0.029 0.012/0.21 0.0013/0.002 0.013 0.83/0.14 0.013/0.019 3/5 

Reporting limit 0.10 0.10 0.01 0.05/0.1 5.0 0.05 10 

1Duplicate sample.2Median values were calculated using estimated values as absolute numbers.3Analytical laboratory reported two minimum detection levels for some constituents.

Table 7. Nutrient and other selected constituents detected in water samples collected at Fort Chaffee, Arkansas, 2002 through 2004.—Continued[e, value is between the minimum detection limit and the reporting limit and is an estimated value; --, constituent not detected for specified event; n/a, not applicable; bold, indiced the median maximum of 14 sites sampled in the Ozark Plateaus, mg/L, milligrams per liter; col./100 mL, colonies per 100 milliliters; NAWQA, National Water-Quality Assemean concentration]

Sampling site

Sampling

type

Data

sampled

Ammonia

as N

(mg/L)

Nitrite plus

nitrate as N

(mg/L)

Nitrite

as N

(mg/L)

Total ammonia

plus organic

nitrogen as N

(mg/L)

Orthophosphorus

as P

(mg/L)

Total

phosphorus

(mg/L)

Total

dissolv

solids

(mg/L
Table 8. Flow volumes and event mean concentrations for constituents detected above the laboratory minimum detection limit at four sites for the 

same storm event at Fort Chaffee, Arkansas, May 2003.

[Concentrations above the laboratory minimum detection limit and less than the reporting limit are shown as actual values (rather than estimated values, see tables 

6 and 7 for estimated values); μg/L, micrograms per liter; --, constituent was not detected; bold text denotes highest value of the four sites; N, nitrogen; mg/L, milligrams per liter; P, phosphorus; ft3, cubic feet]

Ammonia as N (mg/L)

Nitrite as N (mg/L)

Nitrite plus nitrate as N (mg/L)

Total ammonia plus organic

nitrogen as N (mg/L)

Orthophosphorus as P (mg/L)

Total phosphorus (mg/L)

Antimony (μg/L)

Arsenic (μg/L)

Barium (μg/L)

Cadmium (μg/L)

Chromium (μg/L)

Cobalt (μg/L)

Copper (μg/L)

Lead (μg/L)

Manganese (μg/L)

Mercury (μg/L)

Molybdenum (μg/L)

Nickel (μg/L)

Selenium (μg/L)

Zinc (μg/L)

2,4-D (μg/L)

Tetryl (μg/L)

Hexane extractable material

(HEM) (mg/L)

Total dissolved solids (mg/L)

Total suspended solids (mg/L)

Accumulated flow volume (ft3)

18 Water Quality, Fish Tissue, and Bed Sediment Monitoring in Waterbodies of Fort Chaffee Maneuver Training Center,

Arkansas, 2002-2004

Constituent Big Creek Site 1 Big Creek Site 4 Vache Grasse Site 0 Vache Grasse Site 2

-- 0.07 0.36 0.17

0.01 0.01 0.08 0.02

0.41 0.09 1.7 0.37

0.33 0.03 0.73 0.32

-- -- 0.27 0.02

0.053 0.038 0.250 0.068

0.20 0.27 0.28 0.16

0.37 0.48 6.0 0.63

25 15 29 28

0.14 -- -- 0.06

0.74 0.54 0.67 0.43

0.24 0.16 0.58 0.35

2.6 1.2 1.7 0.95

0.31 0.20 -- --

10 54 150 180

0.029 0.017 0.03 0.038

0.096 0.150 0.49 0.27

2.5 1.1 2.6 1.8

-- -- 0.24 --

13 6.4 19 6.5

-- -- 0.91 --

-- -- 0.01 --

4.4 4.1 4.8 3.9

110 77 170 160

270 21.0 130 26

148,000 1,336,000 2,911,000 52,100,000
Table 9. Computed storm loads for stream sites sampled at Fort Chaffee, Arkansas, May 2003.

[Loads are in pounds; --, constituent was not detected; bold text denotes highest value calculated at the four sites]

Ammonia as N

Nitrite plus nitrate as N

Nitrite as N

Orthophosphorus as P 

Total ammonia plus organic nitrogen as N

Total phosphorus

Antimony

Arsenic

Barium

Cadmium

Chromium

Cobalt

Copper

Lead

Manganese

Mercury

Molybdenum

Nickel

Selenium

Zinc

2,4-D

Tetryl

Hexane extractable material (HEM)

Total dissolved solids

Total suspended solids

 Constituents Detected in Water, Fish Tissue, and Bed Sediment 19

Constituent Big Creek Site 1 Big Creek Site 4 Vache Grasse Site 0 Vache Grasse Site 2

-- 6.08 65.4 553

3.80 7.25 308.7 1,203

0.13 0.62 14.5 78.0

-- -- 49 65

3.05 2.83 132.6 1,040

0.49 3.17 45.4 221

<0.01 0.02 0.05 0.52

<0.01 0.04 1.09 2.05

0.23 1.25 5.27 91.0

<0.01 -- -- 0.20

0.01 0.04 0.12 1.4

<0.01 0.01 0.11 1.14

0.02 0.10 0.31 3.09

<0.01 0.02 -- --

0.09 4.50 27.2 585

<0.01 <0.01 0.01 0.12

<0.01 0.01 0.09 0.88

0.02 0.09 0.47 5.85

-- -- 0.04 --

0.12 0.53 3.45 21.1

-- -- 0.17 --

-- -- 0.002 --

40.7 342 872 12,700

1,000 6,400 31,000 520,000

2,500 1,800 24,000 85,000
Table 10. A comparison of actual storm loads measured at Vache Grasse Creek Site 0 to flow-normalized storm loads at Big Creek Site 4, May 2003.

[Loads are in pounds; normalized event loads at Big Creek Site 4 were obtained by dividing the event flow volume at Vache Grasse Creek Site 0 by the event flow 

volume at Big Creek Site 4 and then multiplying that quotient by the event load measured at Big Creek Site 4; ft3

, cubic feet; bold, denotes highest event load; 

n/a, constituent not detected at one or more sites; N, nitrogen; P, phosphorus; --, not detected]

Ammonia as N

Nitrite plus nitrate as N

Nitrite as N

Orthophosphorus as P 

Total ammonia plus organic nitrogen as N

Total phosphorus

Antimony

Arsenic

Barium

Cadmium

Chromium

Cobalt

Copper

Lead

Manganese

Mercury

Molybdenum

Nickel

Selenium

Zinc

2,4-D

Tetryl

Hexane extractable material (HEM)

Total dissolved solids

Total suspended solids

Stormflow volume (ft3)

20 Water Quality, Fish Tissue, and Bed Sediment Monitoring in Waterbodies of Fort Chaffee Maneuver Training Center,

Arkansas, 2002-2004

Constituent

Vache Grasse Site 0

(actual)

Big Creek Site 4

(actual)

Big Creek Site 4

(normalized) Load ratios1

65.4 6.08 13.26 4.9

309 7.25 15.80 19.5

14.5 0.62 1.36 10.7

49.0 -- -- n/a

133 2.83 6.17 21.5

45.4 3.17 6.90 6.6

0.05 0.02 0.05 1.0

1.09 0.04 0.09 12.5

5.27 1.25 2.72 1.9

-- -- -- n/a

0.12 0.04 0.10 1.2

0.11 0.01 0.03 3.6

0.31 0.10 0.22 1.4

-- 0.02 0.04 n/a

27.2 4.50 9.81 2.8

0.01 0.00 0.00 1.9

0.09 0.01 0.03 3.3

0.47 0.09 0.20 2.4

0.04 -- -- n/a

3.45 0.53 1.16 3.0

0.17 -- -- n/a

< 0.01 -- -- n/a

872 342 745 1.2

30,871 6,416 13,983 2.2

23,607 1,750 3,813 6.2

2,911,000 1,336,000 2,911,000

1Load ratios were calculated by dividing loads for Vache Grasse Creek Site 0 by the normalized load for Big 

Creek Site 4.
DAILY MEAN STAGE, SPECIFIC CONDUCTANCE,

AND TURBIDITY

APRIL 2004

Stage (in feet, times 10)

Specific conductance (in microsiemens per centimeter

at 25 degrees Celsius, divided by 10)

Turbidity (in nephlometric turbidity units, divided by 10)

Constituents Detected in Water, Fish Tissue, and Bed Sediment 21

Figure 2. Continuous stage, specific conductance, and turbidity data collected at Vache Grasse Creek Site 2, April 2004.
22 Water Quality, Fish Tissue, and Bed Sediment Monitoring in Waterbodies of Fort Chaffee Maneuver Training Center,

Arkansas, 2002-2004

Fish Tissue

DDT and metabolites of DDT, heptachlor, and endrin 

ketone were the only insecticides detected in fish fillet samples 

(table 11). Some of these results are questionable, however, 

because detections of heptachlor and endrin ketone, and four of 

nine detections for DDT or DDT metabolites were in samples 

that had an associated laboratory blank sample that also contained these compounds. Although one detection for DDT in 

fish tissue exceeded the RL, all DDT concentrations in fish tissue were lower than in bed sediment samples (table 4). 

Trace element detections were common in fish liver samples (table 12) and less common in fillet samples (table 13). 

Concentrations in fish liver samples were compared to median 

concentrations from 31 to 281 sites (depending on the constituent) analyzed nationally by the NAWQA program (Zappia, 

2002). Concentrations in fish livers exceeded the NAWQA 

median at one site for mercury (Darby Lake) and at one site for 

nickel (Vache Grasse Creek Site 0). The concentration of mercury in fish livers from Darby Lake was 66 percent higher than 

the NAWQA median at 285 sites and the concentration of 

nickel in fish livers collected from Vache Grasse Creek Site 0 

was 45 percent higher than the median of 140 NAWQA sites 

(Zappia, 2002). Detections for all trace element constituents in 

fillet samples were less than the RL except for chromium, copper and mercury (table 13); however, chromium data are suspect because this constituent also was detected in associated 

blank samples. Mercury concentrations in edible fish tissue, 

which are a widespread concern in the United States (U.S. Environmental Protection Agency, 2001), exceeded an USEPA criterion for methylmercury of 300 μg/kg in four of nine samples; 

however, concentrations are typical of mercury concentrations 

in fish tissues for the State of Arkansas (U.S. Environmental 

Protection Agency, 2001b).

Table 11. Concentrations of organic compounds detected in fish fillets collected at Fort Chaffee, Arkansas, 2002. 

[Values are in micrograms per kilogram; DDD, dichlorodiphenyldichloroethane; DDE, dichlorodiphenyldichloroethylene;

DDT, dichlorodiphenyltrichloroethane; c, constituent detected in associated laboratory blank sample; e, value is less than the reporting

limit and was estimated by the analytical laboratory]

Big Creek at Site 2

Big Creek at Site 4

Christmas Knob Lake

Darby Lake

Engineer Lake

Mendenhall Swamp Lake

Vache Grasse Creek Site 0

Vache Grasse Creek Site 1

Vache Grasse Creek Site 2

Minimum detection limit

Laboratory reporting limit

Site 4,4’-DDD 4,4’-DDE 4,4’-DDT Heptachlor Endrin ketone

<0.6 <0.6 <1.4 0.63c <0.6

<0.6 <0.6 <1.4 <0.6 <0.6

2.6e 2.2e <1.4 <0.6 <0.6

<0.6 1.7c <1.4 <0.6 0.92c

2.5c 7.6 1.7c <0.6 <0.6

<0.6 1.4c <1.4 <0.6 <0.6

<0.6 <0.6 <1.4 <0.6 <0.6

<0.6 1.4e <1.4 <0.6 <0.6

0.73c <0.6 <1.4 <0.6 <0.6

0.6 0.6 1.4 0.6 0.6

6 666 6
Table 12. Trace element concentrations in fish livers collected at Fort Chaffee, Arkansas, 2002.

[Concentrations are in micrograms per kilogram; ND, not detected; e, estimated value; c, constituent detected in associated laboratory blank sample; (31), number of National Wa

(NAWQA) sites where fish livers were analyzed; bold text represents samples that exceeded NAWQA median values; n/a, not analyzed]

240(285) 400(140) 5,300(273) 600(172) 

Antimony Arsenic Beryllium Cadmium Chromium Copper Lead Mercury Nickel Selenium Silver Thalliu

Big Creek at Site 2 <200 160e ND 230 270c 5,000 45e 39e 190c 2,000 31e,c ND Big Creek at Site 4 <200 130e ND 290 240c 7,600 22e 160 130c 1,500 71e,c 4.4e Christmas Knob Lake <200 43e 2.7e 30e 390c 4,200 ND 11e 96e,c 330e 24e,c ND Darby Lake <200 110e ND 250 460c 10,000 73e 400 72e,c 1,800 19e,c ND Engineer Lake <200 190e ND 640 380c 3,400 ND 230 160c 1,800 25e,c 2.1e Mendenhall Swamp Lake <200 110e 3.1e 630 370c 4,400 32e 98e 79e,c 1,700 29e,c 3.0e Vache Grasse Creek Site 0 <200 100e ND 180 260c 3,000 ND 100 580c 1,300 16e,c 6.2e Vache Grasse Creek Site 1 <200 68e ND 150 390c 1,700 ND 96e 74e,c 1,100 6.4e,c 2.4e Vache Grasse Creek Site 2 <200 95e ND 250 240c 3,500 ND 100 95e,c 1,100 43e,c 3.0e Minimum detection limit 20 7.6 2.3 2.7 34 61 20 5.9 11 18 2.0 2.0 Reporting limit 200 500 100 100 200 200 100 100 100 500 100 100 Median <20 110 <2.3 250 370 4,200 <20 100 96 1,500 25 3.0 NAWQA median1

1Zappia (2002).

200 (31) 400 (189) (280)2

2Reporting limit for beryllium in fish tissue sampled for NAWQA Program was 100 μg/kg.

1,500 (238) 700 (280) 55,900 (281) 320(97) n/a
Table 13. Trace element concentrations in fish fillets collected at Fort Chaffee, Arkansas, 2002.

[Concentrations are in micrograms per kilogram; ND, not detected; e, estimated value; c, constituent detected in associated blank sample]

Antimony Arsenic Beryllium Cadmium Chromium Copper Lead Mercury Nickel Selenium Silver Thallium Zinc Big Creek at Site 2 ND 60e ND ND 310c 250 ND 180 15e,c 490e ND ND 5,400c

Big Creek at Site 4 ND 23e ND ND 320c 240 ND 550 19e,c 330e ND ND 4,800cChristmas Knob Lake ND 15e ND ND 440c 250 ND 280 40e,c 400e 25e,c ND 3,800cDarby Lake ND 21e ND ND 460c 170e ND 580 30e,c 460e 15e,c ND 5,300cEngineer Lake ND 59e ND ND 490c 200 ND 350 31e,c 470e 19e,c ND 4,500cMendenhall Swamp Lake 96e 16e 2.6e 3.6e 420c 190e ND 18e 33e,c 69e 27e,c 2.4e 6,000cVache Grasse Creek Site 0 ND 30e ND ND 300c 230 ND 280 34e,c 280e ND ND 4,700cVache Grasse Creek Site 1 ND 31e ND ND 480c 250 ND 220 33e,c 330e 8.9e,c ND 4,900cVache Grasse Creek Site 2 ND 63e ND ND 470c 260 ND 420 200c 420e ND ND 4,800cMinimum detection limit 20 7.6 2.3 2.7 34 61 20 5.9 11 18 2.0 2.0 130Reporting limit 200 500 100 100 200 200 100 100 100 500 100 100 1,000Median <20 30 <2.3 <2.7 440 240 <20 280 33 400 8.9 <2.0 4,800
Possible Relations of Sediment Deposition to Erosion and Turbidity 25

Bed Sediment

Detection of DDT in bed-sediment samples indicates that 

previous activities on post have influenced environmental conditions. Of the 44 organic compounds that were analyzed in bed 

sediment, only two were detected above the MDL. The two 

compounds detected were dichlorodiphenyltrichloroethane 

(4,4’,DDT) and a DDT metabolite dichlorodiphenyldichloroethylene (4,4’,DDE) and both detections occurred at Grayson 

Creek (fig. 1, table 14), the site closest to the administrative and 

residential area of Fort Chaffee (known as the cantonment area). 

Although both detections were lower than the RL (and are estimated values), concentrations for total DDT at Grayson Creek 

exceeded median concentrations at 45 of 46 NAWQA study 

units (including about 700 sites) (Chalmers, 2002). DDT is a 

chemical compound that was used primarily as an insecticide 

until it was banned in 1972. Low levels of DDT and its metabolites are common in bed-sediment samples collected throughout the United States and result both from widespread use and 

the persistent nature of this compound (Nowell and others, 

1999).

Concentrations of some trace elements in bed sediments 

(as well as other media) sampled for this study also could have 

a relation to on-post activities or conditions. Detections at low 

to moderate concentrations are to be expected, however, 

because these constituents occur naturally in soils and, in appropriate amounts, are considered essential or beneficial to both 

plants and humans (Pais and Jones, 1997). Trace element concentrations were compared to bed sediment and geochemical 

background concentrations established by two trace element 

studies conducted previously in the United States (table 15; 

MacDonald and others, 2000; Gustavsson and others, 2001). 

Trace element concentrations in bed-sediment samples at one or 

more sites slightly exceeded estimated geochemical background concentrations for western Arkansas for arsenic, copper, 

lead, manganese, nickel, and zinc (table 15; Gustavsson and 

others, 2001), and slightly exceeded lowest effect level criteria 

at one site each for arsenic and at two sites for nickel. The site 

located on Grayson Creek had concentrations that were above 

background concentrations for all six of the aforementioned 

constituents, and arsenic and nickel concentrations exceeded 

lowest effect level (toxicity) criteria to aquatic life; 9,790 and 

22,700 μg/kg, respectively (table 15; MacDonald and others, 

2000). 

Aside from potential contamination at Grayson Creek, two 

possible explanations for elevated trace element concentrations 

in Fort Chaffee streams are relatively high background concentrations in soils of western Arkansas (Gustavsson and others, 

2001), and field observations of excessive bed sediment deposition at Fort Chaffee. Excessive bed sediment deposition rates 

can lead to high biochemical oxygen demand which ultimately 

results in anoxic conditions. In this situation, trace elements 

favored by a reducing environment (such as manganese) can 

occur in bed sediments in high concentrations (Mitsch and Gosselink, 1993). 

Possible Relations of Sediment Deposition 

to Erosion and Turbidity 

Excessive bed sediment deposition observed at Fort Chaffee also could have a relation to on-post activities or conditions. 

Sedimentation in Fort Chaffee waterbodies may be a possible 

consequence of soil erosion resulting from training activities 

(tank exercises and disruption of the landscape by exploding 

ordnances) and an extensive road system. Turbidity in streams 

may be a surrogate for erosion and bed sedimentation. Mean 

turbidity for 4 of 9 months for which data were collected, at the 

most downstream site on Vache Grasse Creek, exceeded 40 

nephlometric turbidity units (NTUs); a state stream-stormflow 

standard for the Arkansas River Valley (Arkansas Department 

of Environmental Quality, 2004). Turbidity and excessive bed 

sediment deposition are chronic physical impairments that may 

be influencing the ecological integrity of Fort Chaffee streams 

to some degree. 

Effects of Land Use Both On and Off Post

The constituents detected in water, fish tissue, and bedsediment samples collected in this study indicate that land use 

activities both on and off post are influencing environmental 

conditions in waterbodies of Fort Chaffee. Contaminants such 

as explosives that were sometimes detected in water samples 

have an obvious relation to military training; however, the 

occurrence and locations of some nutrient, insecticide, and 

trace-element detections indicate that land use both on and off 

post also could be influencing environmental conditions to 

some degree. 

Constituent concentrations at sites on Vache Grasse Creek, 

and particularly at Site 0, indicate that environmental conditions 

were being influenced by an off-post source. Sites on Vache 

Grasse Creek had the highest number of constituent detections 

and the highest concentrations detected of all other sites for 

most media sampled, and also had much higher event-mean 

storm concentrations and normalized storm loads than sites on 

Big Creek. 

Table 14. Organic compounds detected in bed-sediment samples at Fort 

Chaffee, Arkansas, 2002.

[Concentrations are in micrograms per kilogram; DDE, dichlorodiphenyldichloroethylene; DDT, dichlorodiphenyltrichloroethane;e, value is less than the 

reporting limit and was estimated by the analytical laboratory]

Site 4,4’-DDE 4,4’-DDT

Grayson Creek 19e 22e

Minimum detection limit 13 15

Reporting limit 51 51
Table 15. Concentrations and associated toxicity values for trace elements analyzed in bed-sediment samples collected at Fort Chaffee, Arkansas, 

2002.

[Concentrations are reported as micrograms per kilogram except for TOC (total organic carbon), which is grams per kilogram; bold text represents samples that 

exceeded “lowest effect level” criteria and background concentrations; green text indicates values that met or exceeded only background concentrations; c, constituent detected in associated blank sample; e values were estimated; n/a, criteria not available; NS, not sampled]

26 Water Quality, Fish Tissue, and Bed Sediment Monitoring in Waterbodies of Fort Chaffee Maneuver Training Center,

Arkansas, 2002-2004

Antimony Arsenic Barium Beryllium Cadmium Chromium Cobalt Copper Lead

Big Creek Site 1 13e,c 5,100 100,000c 660 89e,c 22,000c 14,000 8,300 12,000

Big Creek Site 2 79e,c 3,200 68,000c 520 42e,c 15,000c 8,400 5,200 8,300

Big Creek Site 3 36e,c 6,900 160,000c 910 200e,c 29,000c 14,000 12,000 16,000

Big Creek Site 4 18e,c 3,900 88,000c 600 63e,c 17,000c 9,300 5,700 10,000

Christmas Knob Lake 67e,c 84e 2,100c 16e <4 500e,c 190e 6,000c 220ec

Darby Lake 18e,c 4,600 93,000c 650 96e,c 17,000c 11,000 14,000 12,000

Engineer Lake 36e,c 350e 4,400c 32e <4 940c 330 380ec 370c

Gin Creek 12e,c 4,800 61,000c 560 46e,c 21,000c 8,400 5,600 9,600

Grayson Creek 26e,c 10,000 160,000c 950 330c 29,000c 19,000 17,000 28,000

Mendenhall Swamp Lake 130e,c 270e 5,800c 52e 14e 1,300c 470 1,500c 1,000c

Vache Grasse Creek Site 1 14e,c 2,900 61,000c 420 70e,c 10,000c 7,000 8,400 7,500

Vache Grasse Creek Site 21 24e,c 5,700 110,000c 900 140e 22,000c 13,000 9,200 16,000

Vache Grasse Creek Site 21 19e,c 5,000 100,000c 740 100e 20,000c 12,000 8,100 14,000

Minimum detection limit2 7 44 62 11 4 47 3 39 11

Reporting limit 517 1,283 258 258 258 517 258 517 258

Median (for Fort Chaffee samples) 23.75 4,250 78,000 580 79.5 17,000 8,850 7,150 9,800

Lowest effect level

(MacDonald and others, 2000)

n/a 9,790 n/a n/a 990 43,400 n/a 31,600 35,800

Highest effect level

(MacDonald and others, 2000)

n/a 33,000 n/a n/a 4,980 111,000 n/a 149,000 128,000

Background3 n/a 10,000 260,000 n/a n/a 50,000 n/a 16,900 16,600
Table 15. Concentrations and associated toxicity values for trace elements analyzed in bed-sediment samples collected at Fort Chaffee, Arkansas, 

2002.--Continued

[Concentrations are reported as micrograms per kilogram except for TOC (total organic carbon), which is grams per kilogram; bold text represents samples that 

exceeded “lowest effect level” criteria and background concentrations; green text indicates values that met or exceeded only background concentrations; c, constituent detected in associated blank sample; e values were estimated; n/a, criteria not available; NS, not sampled]

 Effects of Land Use Both On and Off Post 27

Manganese Mercury Molybdenum Nickel Selenium Silver Thallium Zinc TOC

Big Creek Site 1 9,100c 20e 290e,c 20,000 480e 74e,c 120e 48,000 13

Big Creek Site 2 620,000c 13e 360c 12,000 370e 84e,c 100e 28,000 7.1

Big Creek Site 3 710,000c 5.5e 440c 23,000 650e 140e,c 190e 57,000 16

Big Creek Site 4 500,000c 16e 280e,c 13,000 430e 67e,c 100e 31,000 8

Christmas Knob Lake 16,000c <7 99e,c 340 85e 19e,c 29e 1,400e 27

Darby Lake 890,000c 43e 390e,c 16,000 550e 87e,c 120e 59,000 17

Engineer Lake 36,000c <9 58e,c 700c <127 13e,c 6.6e 2,300e 20

Gin Creek 300,000c 10e 330c 14,000 430e 60e,c 74e 31,000 5.9

Grayson Creek 13,000c 21e 670c 24,000 680e 130e,c 140e 79,000 13

Mendenhall Swamp Lake 29,000c ND 290e,c 970c 70e 39e,c 57e 5,000 24

Vache Grasse Creek Site 1 6,000c 19e 250e,c 10,000 360e 62e,c 80e 37,000 5.8

Vache Grasse Creek Site 21 790,000c 30e 300e 18,000 510e 130e,c 140e 52,000 7.4

Vache Grasse Creek Site 21 710,000c 26e 260e 16,000 450e 88e,c 120e 45,000 NS

Minimum detection limit2 107 4-11 6 34 127 6 3 500-1,600 0.59

Reporting limit2 465 48-150 517 258 1,283 258 258 1,400-4,600 2

Median (for Fort Chaffee samples) 168,000 19 290 13,500 430 70.5 100 34,000 13

Lowest effect level

(MacDonald and others, 2000)

n/a 180 n/a 22,700 n/a n/a n/a 121,000 n/a

Highest effect level

(MacDonald and others, 2000)

n/a 1,060 n/a 48,600 n/a n/a n/a 459,000 n/a

Background3 800,000 65 n/a 16,700 740 n/a n/a 49,000 n/a

1

Duplicate samples were analyzed at Vache Grasse Site 2.

2

Analytical laboratory reported two minimum detection limits for some constituents and reporting limits.

3Estimated geochemical background for western Arkansas (Gustavsson and others, 2001).
28 Water Quality, Fish Tissue, and Bed Sediment Monitoring in Waterbodies of Fort Chaffee Maneuver Training Center,

Arkansas, 2002-2004

Constituent concentrations at other sites provide evidence 

that environmental conditions are being influenced by on-post 

activities. Explosives and oil and grease were the most common 

organic constituents detected above the MDL in water samples. 

Bed-sediment samples from one site located on Grayson Creek, 

and nearest the administrative and residential (cantonment) 

area, had detections for several trace elements that were above 

background concentrations and concentrations for arsenic and 

nickel at this site exceeded lowest effect level criteria established by the U.S. Environmental Protection Agency. The site 

on Grayson Creek also had the only detections of DDT metabolites in bed sediment. Turbidity and excessive bed sediment 

deposition are chronic physical impairments that probably are 

influenced by on-post activities and that could be influencing 

the ecological integrity of Fort Chaffee streams to some degree. 

Summary

The Fort Chaffee Maneuver Training Center is a facility 

used to train as many as 50,000 Arkansas National Guardsmen 

each year. Due to the nature of ongoing training and also to a 

poor understanding of environmental procedures that were 

practiced in the WWII era, areas within Fort Chaffee have the 

potential to be sources of a large number of contaminants. 

Because some streams flow on to Fort Chaffee, there is also the 

potential for sources that are off post to affect environmental 

conditions on post. To address these concerns the USGS in 

cooperation with the ANG, conducted a study to document constituent concentrations in water, fish tissue, and bed sediment 

collected from waterbodies on Fort Chaffee from September 

2002 through July 2004. Constituent concentrations detected in 

the three media and measured at 13 sites were compared to 

national and regional criteria when available. 

Concerning constituents that were analyzed in water samples, sites on Vache Grasse Creek, and particularly Site 0, a site 

immediately downstream from an off-post wastewater-treatment facility, had both the highest number of detections and the 

highest concentrations detected of all the other sites sampled. 

Of the 55 organic constituents analyzed in water samples, only 

10 were detected above the minimum detection limit (MDL) but 

four of those were explosives. No priority pollutants detected in 

water—arsenic, copper, lead, nickel, or zinc—were above 

aquatic life criteria established by the U.S. Environmental Protection Agency. All detections for arsenic and lead above the 

laboratory reporting limit (RL) occurred in high-flow event 

samples at Vache Grasse Creek Site 0. Five of the seven detections each for nickel and zinc also were from sites located on 

Vache Grasse Creek. Detections for copper were more common 

in the Big Creek drainage than in the Vache Grasse Creek drainage (six of seven detections). The estimated concentration of 

cadmium (above MDL but below RL) in a stormflow sample 

from Big Creek was above the aquatic life criterion.

Nutrient concentrations tended to be higher at sites located 

on Vache Grasse Creek than at other sampling sites. Of the three 

sites on Vache Grasse, and similar to other constituents, nutrient 

concentrations were highest at Vache Grasse Creek Site 0. High 

nutrient concentrations at this site could indicate released or 

overflowing effluent, which would provide some explanation 

for why total phosphorus concentrations were higher in baseflow samples than in stormflow samples. 

Event-mean storm concentrations and storm loads calculated from stormflow samples at two sites each for Big and 

Vache Grasse Creeks indicate that storm loads were highest at 

the two Vache Grasse Creek sites for 24 of the 25 constituents 

detected. Further evaluation by normalizing storm loads at Big 

Creek to storm loads at Vache Grasse Creek by streamflow indicate that normalized event loads at Vache Grasse Creek were 

about two or more times higher than those at Big Creek for 15 

of the 25 constituents measured.

Manganese and barium are not considered to be priority 

pollutants by USEPA but were detected above the RL for every 

water sample collected. Manganese concentrations tended to be 

higher in lake samples than in stream samples. 

Mercury concentrations in edible fish tissue, which are a 

widespread concern in the United States (U.S. Environmental 

Protection Agency, 2001), exceeded an USEPA criterion for 

methylmercury of 300 μg/kg in four of nine samples; however, 

concentrations are typical of mercury concentrations in fish tissues for the State of Arkansas (U.S. Environmental Protection 

Agency, 2001b). The concentration of mercury in fish livers 

from Darby Lake was 66 percent higher than the NAWQA 

median at 285 sites and the concentration of nickel in fish livers 

from Vache Grasse Creek Site 0 was 45 percent higher than the 

NAWQA median at 140 sites. DDT and metabolites of DDT 

were the only organic compounds detected in bed sediment and 

were the most common compound detected in fish tissue samples. One site located on Grayson Creek, and nearest the administrative and residential (cantonment) area, had the only detections of DDT metabolites in bed sediment and values reported 

exceeded median concentrations at 45 of 46 NAWQA study 

units (including about 700 sites).

Trace element concentrations in bed-sediment samples 

slightly exceeded estimated geochemical background concentrations for soils in western Arkansas for arsenic, copper, lead, 

manganese, nickel, and zinc at one or more sites and slightly 

exceeded lowest effect level (toxicity) criteria at one site for 

arsenic and at two sites for nickel. The site located on Grayson 

Creek had detections that were above background concentrations for all six of the aforementioned constituents and, for 

arsenic and nickel, detections exceeded lowest effect level (toxicity) criteria established by the U.S. Environmental Protection 

Agency. 

Concentrations of some trace elements in all media sampled for this study could be a consequence of on-post activities 

or conditions. One possible explanation for elevated trace element concentrations is that background concentrations seem to 

be higher in western Arkansas than for most other regions. 

However, another possible reason may be the redox potential of 

the aquatic environments sampled. Accumulated bed sediments 

and organic material in the bottom substrate may result in a high 
References 29

biochemical oxygen demand and a reducing environment for 

several of the waterbodies sampled, particularly where large 

amounts of sediments have been deposited. In this situation, 

trace elements such as manganese can occur in sediments in 

high concentrations, and under these reduced conditions their 

solubility (ability to mix with water) can increase. Turbidity 

may be a good surrogate for bed sedimentation and soil erosion. 

Mean turbidity for four of nine months for which data were collected exceeded 40 nephlometric turbidity units (NTUs); a state 

stream-stormflow standard for the Arkansas River Valley.

The constituents detected in water, fish tissue, and bedsediment samples collected in this study indicate that land use 

activities both on and off post are influencing environmental 

conditions in waterbodies of Fort Chaffee. Contaminants such 

as explosives that were sometimes detected in water samples 

have an obvious relation to military training, and various chemical compounds used in the cantonment area since the WWII era 

may be the source of contamination in Grayson Creek. Elevated 

contaminant concentrations and storm loads in Vache Grasse 

Creek, particularly at Site 0, suggest that an off-post source 

could be impairing water quality. Some trace elements detected 

may result from the combined effects of sedimentation (a possible consequence of soil erosion resulting from training activities and an extensive road system) and trace element concentrations in soils that are higher than for most other regions. 

Turbidity data collected at the most downstream site on Vache 

Grasse Creek, and observations of substantial sediment deposition in both Vache Grasse and Big Creeks suggest that turbidity 

and excessive bed sediment deposition are chronic physical 

impairments that may be influencing the ecological integrity of 

Fort Chaffee streams. 

References

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state of Arkansas, accessed 10/27/04 at URL http://

www.adeq.state.ar.us/regs/default.htm

Chalmers, Ann, 2002, Trace elements and organic compounds 

in streambed sediment and fish tissue of coastal New 

England streams, 1998-99: U.S. Geological Survey WaterResources Investigations Report 02-4179, 30 p.

Crawford, J.K., and Luoma, S.N., 1993, Guidelines for studies 

of contaminants in biological tissues for the National WaterQuality Assessment Program: U.S. Geological Survey OpenFile Report 92-494, 69 p.

Davis, J.V., and Bell, R.W., 1998, Water-quality assessment of 

the Ozark Plateaus study unit, Arkansas, Kansas, Missouri, 

and Oklahoma--Analysis of information on nutrients, suspended sediment, and suspended solids, 1970-92: U.S. Geological Survey Water-Resources Investigations Report 95-

4042, 112 p.

Fenneman, N.M., 1938, Physiography of the eastern United 

States: New York, McGraw-Hill, 714 p.

Gustavsson, N., Bølviken, B., Smith, D.B., and Severson, R.C., 

2001, Geochemical landscapes of the conterminous United 

States- New map presentations for 22 elements: U.S. Geological Survey Professional Paper 1648, 38 p.

Haley, B.R., Glick, E.E., Bush, W.V., Clardy, B.F., Stone, C.G., 

Woodward, M.B., and Zachry, D.L., 1993, Geologic map of 

Arkansas: Arkansas Geological Commission, scale 

1:500,000.

Lamb, T.E., 1978, Water-quality investigation of the Vache 

Grasse Creek Drainage, Sebastian County, Arkansas: U.S. 

Geological Survey Open-File Report 78-903, 24 p.

MacDonald, D.D., Ingersoll, C.G., Berger, T.A., 2000, Development and evaluation of consensus-based sediment quality 

guidelines for freshwater ecosystems: Archives of Environmental Contamination and Toxicology, v. 39, p. 20-31.

Mitsch W.J., and Gosselink, J.G., 1993, Wetlands, (2nd ed): 

Van Nostrand Reinhold, 722 p. 

Nowell, L.H., Capel, P.D., and Dileanis, P.D., 1999, Pesticides 

in stream sediment and aquatic biota-Distribution, trends, 

and governing factors, in Gilliom, R.J., ed., Pesticides in the 

hydrologic system: U.S. Geological Survey National WaterQuality Assessment Program, v. 4, 1001 p. 

Pais, I., and Jones, J. B., Jr., 1997, Handbook of trace elements 

in the environment: CRC Press, 223 p. 

Petersen, J.C., 1988, Statistical summary of selected waterquality data (water years 1975 through 1985) for Arkansas 

rivers and streams: U.S. Geological Survey Water-Resources 

Investigations Report 88-4112, 189 p.

Rantz, S.E. and others, 1982, Measurement and computation of 

streamflow: U.S. Geological Survey Water Supply Paper 

2175, 631p.

Shelton, L.R., and Capel, P.D., 1994, Guidelines for collecting 

and processing samples of stream bed sediment for analysis 

of trace elements and organic compounds for the National 

Water-Quality Assessment Program: U.S. Geological Survey 

Open-File Report 94-458, 20 p.

Stober, Q.J., 1991, Guidelines for fish sampling and tissue preparation for bioaccumulative contaminants: U.S. Environmental Protection Agency, Environmental Services Division, 

Region 4, Athens, Georgia.

U.S. Department of Defense, 2000, Fort Chaffee History, 

accessed 9/07/2004 at URL http://www.5tharmy.army.mil/

2_393/fort1.htm

U.S. Environmental Protection Agency, 1979, Quality criteria 

for water: U.S. Environmental Protection Agency, Washington, DC,. 259 p.

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U.S. Environmental Protection Agency, 1986a, Methods for 

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U.S. Environmental Protection Agency, 1986b, Test methods 

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SW846 (3rd ed): U.S. Environmental Protection Agency.
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Arkansas, 2002-2004

U.S. Environmental Protection Agency, 1993, Drinking water 

criteria document for manganese, accessed 11/02/2004 at 

URL http://www.epa.gov/waterscience/library/wqcriteria/

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U.S. Environmental Protection Agency, 1997, Barium compounds; toxic chemical release reporting; Community Rightto-Know, U. S. Environmental Protection Agency Federal 

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/www.epa.gov/waterscience/criteria/aqlife.html 

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APPENDIXES

Appendix 1. Sampling details and field parameters for lake sampling sites at Fort Chaffee, Arkansas, 2002 through 2003.

[°C, degrees Celsius; mg/L, milligrams per liter; μS/cm, microsiemens per centimeter at 25 degrees Celsius; --, field meter malfunction, no data collected]

Sampling site

Sample

type

Date

sampled

Average

sample

depth

(feet)

Average

total

depth

(feet)

Water

temperature

(° C)

Dissolved 

oxygen

(mg/L)

Specific

conductance

(μS/cm) pH

Christmas Knob Lake Baseflow 9/24/2002 23.3 46

Christmas Knob Lake Baseflow 9/24/2002 22.4 68

Christmas Knob Lake Stormflow 12/30/2003 7.3 56

Christmas Knob Lake Stormflow 12/30/2003 7.1 56

Darby Lake Baseflow 9/23/2002 24.4 46

Darby Lake Baseflow 9/23/2002 23.5 46

Darby Lake Stormflow 12/29/2003 8.9 72

Darby Lake Stormflow 12/29/2003 8.8 72

Engineer Lake Baseflow 9/24/2002 24.9 42

Engineer Lake Baseflow 9/24/2002 24.4 42

Engineer Lake Stormflow 12/29/2003 8.4 57

Engineer Lake Stormflow 12/29/2003 8.4 57

Mendenhall Swamp Lake Baseflow 9/24/2002 21.3 60

Mendenhall Swamp Lake Baseflow 9/24/2002 21.4 113

Mendenhall Swamp Lake Stormflow 12/30/2003 7.5 63

Mendenhall Swamp Lake Stormflow 12/30/2003 6.7 63

Appendix 33

2.7 6.5 5.4 6.4

9.0 6.5 3.2 6.2

1.3 6.0 5.0 6.9

4.8 6.0 4.5 6.8

2.5 12.4 6.5 6.7

9.7 12.4 5.7 6.6

1.3 5.8 -- 7.5

4.6 5.8 -- 7.5

2.3 9.7 6.8 6.6

9.3 9.7 6.4 6.5

2.0 6.8 8.3 7.1

8.1 6.8 8.1 7.1

2.7 6.2 0.6 5.8

7.0 6.2 1.0 6.0

1.3 4.9 -- 6.8

4.5 4.9 -- 6.7
Appendix 2. Sampling details and results for field and laboratory constituents measured at stream sampling sites on Fort Chaffee, Arkansas, 2002 through 2004.

[°C, degrees Celsius, mg/L, milligrams per liter; μS/cm, microsiemens per centimeter at 25 degrees Celsius; cols./100 mL, colonies per 100 milliliters; ft3/s cubic foot per secon

Sampling site

Sample 

type

Date

sampled

Water

temperature

(° C)

Dissolved 

oxygen

(mg/L)

Specific

conductance

(μS/cm) pH

Fecal

coliformbacteria

(cols./

100 mL)

Discharge

(ft3/s)

Al

Big Creek Site 1 Baseflow 9/18/2002 23.2 4.0 190Big Creek Site 1 Stormflow 3/19/2003 13.0 9.1 77Big Creek Site 1 Eventflow 5/16/2003 -- -- 124Big Creek Site 2 Baseflow 9/17/2002 23.2 4.0 89Big Creek Site 2 Stormflow 3/19/2003 15.6 9.2 45Big Creek Site 3 Baseflow 9/17/2002 25.2 3.4 84Big Creek Site 3 Stormflow 3/19/2003 13.9 9.5 55Big Creek Site 4 Baseflow 9/17/2002 23.1 4.4 113Big Creek Site 4 Stormflow 3/19/2003 13.6 8.8 49Big Creek Site 4 Eventflow 5/17/2003 -- -- 77Big Creek Site 4 Baseflow 9/04/2003 25.2 9.1 106Big Creek Site 4 Stormflow 1/18/2004 8.9 10.4 60Gin Creek Baseflow 9/18/2002 25.1 2.3 151Gin Creek Stormflow 3/20/2003 12.1 9.9 96Grayson Creek Baseflow 9/17/2002 27.5 4.8 153Grayson Creek Stormflow 3/20/2003 12.6 8.6 110Vache Grasse Creek Site 0 Baseflow 11/5/2002 11.1 7.0 257Vache Grasse Creek Site 0 Eventflow 5/17/2003 21.2 4.2 232Vache Grasse Creek Site 0 Baseflow 9/04/2003 26.4 8.2 375Vache Grasse Creek Site 0 Stormflow 1/18/2004 9.7 8.9 179Vache Grasse Creek Site 1 Baseflow 9/18/2002 23.0 4.5 270Vache Grasse Creek Site 2 Baseflow 9/16/2002 27.1 4.8 199Vache Grasse Creek Site 2 Stormflow 5/16/2003 -- -- 246Vache Grasse Creek Site 2 Eventflow 5/18/2003 -- -- 240Vache Grasse Creek Site 2 Baseflow 9/04/2003 25.2 8.7 249Vache Grasse Creek Site 2 Stormflow 1/18/2004 9.0 9.3 125

1Alkalinity and hardness analyses were analyzed only for selected samples.

7.9 300 0 -7.6 7,900 21.1 -7.4 -- -- -6.6 16 0 -8.6 1,630 91.3 -7.1 96 0 -7.6 8,000 37.6 -7.1 196 0 -7.7 18,400 37.6 -7.5 -- -- -7.1 38 0 98.4 640 -- 17.8 1,060 0 -8.7 480 48 -7.1 192 0 -7.5 580 3.8 -7.7 700 17.8 -7.7 600 22.3 -7.7 48 -- 118.2 1,060 -- 37.8 68 0.62 -6.8 52 0.06 -7.3 260 -- -7.3 -- -- -7.4 78 1.82 148.4 1,700 -- 2
Appendix 3. Daily mean values for stream stage data at Vache Grasse Creek Site 2 from November 2003 to July 2004.

[Values are in feet; ---, missing data]

1

2

3

4

5

6

7

8

9

10

11

12

13

14

15

16

17

18

19

20

21

22

23

24

25

26

27

28

29

30

31

Minimum

Maximum

Mean

Appendix 35

Day November December January February March April May June July

1.89 2.46 2.49 2.62 2.47 2.96 3.54 2.65 4.59

1.88 2.43 2.47 2.62 2.48 2.86 3.69 2.45 9.02

1.88 2.41 2.45 2.60 2.54 2.83 3.40 4.47 15.83

1.90 2.40 2.44 2.60 2.63 2.81 3.18 3.13 ---

1.93 2.36 2.42 4.44 3.95 2.71 3.07 2.71 ---

2.06 2.42 2.39 3.93 3.53 2.66 2.95 2.56 3.90

2.69 2.19 2.38 3.40 2.94 2.76 2.92 2.49 3.72

2.43 2.15 2.36 3.29 3.96 2.87 2.80 2.44 ---

2.37 2.25 2.34 3.09 4.68 2.78 2.72 2.40 ---

2.25 2.33 2.33 2.91 4.74 3.62 2.67 2.42 ---

2.11 2.58 2.32 2.85 4.70 4.28 2.69 2.87 ---

2.01 2.45 2.31 2.82 4.68 3.49 2.57 2.97 ---

1.97 2.40 2.34 2.79 4.72 3.23 2.54 --- 3.20

1.95 2.39 2.35 2.76 4.53 3.04 2.58 --- 2.88

1.95 --- 2.36 2.72 3.82 2.96 2.59 2.38 ---

1.93 --- 2.49 2.70 3.25 2.89 2.52 7.35 ---

1.98 2.44 3.60 2.67 4.20 2.81 2.48 12.29 ---

2.41 2.44 3.31 2.64 8.24 2.80 2.47 4.15 2.63

2.77 2.43 2.99 2.63 4.81 2.67 2.43 3.83 2.71

2.65 2.40 2.84 2.62 3.51 2.67 2.38 --- 2.65

2.50 2.39 2.75 2.60 3.29 2.94 2.36 --- 2.58

2.41 2.37 2.70 2.56 3.10 9.06 2.34 7.79 2.50

2.37 2.34 2.65 2.58 2.99 9.38 2.31 7.48 2.47

2.32 2.33 2.61 2.59 3.02 11.29 2.30 --- 2.51

2.55 2.38 3.07 2.54 3.31 13.26 2.30 3.72 2.52

2.45 2.40 3.16 2.50 3.16 5.05 2.30 3.50 2.51

2.43 2.37 2.89 2.47 3.01 3.79 2.29 3.32 2.70

2.44 2.39 2.78 2.47 3.13 3.43 2.32 3.13 2.55

2.54 2.56 2.73 2.46 3.42 3.27 2.32 3.23 ---

2.49 2.62 2.69 --- 3.20 3.26 2.35 4.59 2.53

--- 2.54 2.65 --- 3.02 --- 2.89 --- 2.53

1.88 2.15 2.31 2.46 2.47 2.66 2.29 2.38 2.47

2.77 2.62 3.60 4.44 8.24 13.26 3.69 12.29 15.83

2.25 2.40 2.63 2.81 3.71 4.15 2.65 4.01 3.83
Appendix 4. Daily mean values for water temperature data at Vache Grasse Creek Site 2 from November 2003 to July 2004.

[Temperature in degrees Celsius; ---, missing data]

Minimum

Maximum

Mean

36 Water Quality, Fish Tissue, and Bed Sediment Monitoring in Waterbodies of Fort Chaffee Maneuver Training Center,

Arkansas, 2002-200

Day November December January February March April May June July

1 17.5 6.4 6.3 3.3 9.7 14.1 19.1 24.2 23.3

2 17.3 6.2 7.6 3.9 10.7 14.6 17.1 24.3 22.4

3 17.4 6.5 9.2 3.5 11.4 15.1 16.6 21.5 22.5

4 18.3 6.8 10.1 3.5 12.2 15.3 17.0 22.2 ---

5 17.1 6.4 8.1 3.6 13.4 15.1 18.4 21.5 ---

6 15.1 5.9 5.6 4.9 13.2 15.5 19.6 22.2 25.4

7 13.8 5.7 4.1 4.3 12.5 16.1 20.8 23.6 24.8

8 12.6 6.4 3.7 3.2 11.9 16.8 21.5 24.5 ---

9 12.4 7.9 3.8 3.8 12.5 16.9 21.9 24.2 ---

10 12.3 6.5 3.6 4.6 12.1 15.9 22.4 24.1 ---

11 13.2 5.4 3.5 5.2 12.4 15.7 22.7 24.2 ---

12 14.8 4.9 4.0 5.3 12.0 14.9 22.8 25.2 ---

13 13.1 4.9 5.0 4.6 11.7 14.3 22.6 --- ---

14 11.8 4.7 6.1 4.6 11.3 14.0 21.6 --- 27.8

15 11.4 --- 6.3 4.8 11.5 15.2 20.4 --- ---

16 12.2 --- 6.6 5.1 11.6 16.9 20.2 24.6 ---

17 12.9 4.5 7.6 6.0 11.9 18.6 20.9 24.0 ---

18 13.7 4.4 8.7 6.5 13.6 19.7 21.9 24.2 27.4

19 13.0 4.3 6.7 7.8 14.6 19.7 23.2 24.4 26.6

20 12.0 4.0 4.7 9.3 15.3 19.4 24.4 --- 26.8

21 11.9 4.2 4.5 9.0 15.1 19.1 25.1 --- 27.6

22 12.9 5.5 4.4 9.0 13.9 17.4 25.1 22.0 28.0

23 12.9 6.4 4.4 9.3 14.5 18.8 25.1 22.5 28.1

24 9.9 5.6 5.5 9.8 14.9 18.2 25.1 --- 27.8

25 8.2 5.0 7.1 9.3 14.9 18.4 24.6 23.6 26.5

26 8.1 5.0 7.9 8.6 16.2 18.0 24.4 23.8 ---

27 8.4 5.5 5.4 8.3 17.6 17.7 24.7 23.9 ---

28 7.3 6.8 3.4 8.5 17.9 18.2 25.2 24.3 24.0

29 6.3 6.9 3.4 9.0 16.4 18.7 25.7 24.6 ---

30 6.2 5.9 3.5 --- 16.0 19.0 26.0 23.2 23.3

31 --- 5.5 3.0 --- 14.8 --- 24.6 --- ---

6.2 4.0 3.0 3.2 9.7 14.0 16.6 21.5 22.4

18.3 7.9 10.1 9.8 17.9 19.7 26.0 25.2 28.1

12.5 5.7 5.6 6.2 13.5 16.9 22.3 23.6 25.8
Appendix 5. Daily mean values for specific conductance at Vache Grasse Creek Site 2 from November 2003 to July 2004.

[Values are in microsiemens per centimeter at 25 degrees Celsius; ---, missing data]

Minimum

Maximum

Mean

Appendix 37

Day November December January February March April May June July

1 --- --- 182 113 188 124 134 323 97

2 --- 310 186 115 197 118 127 299 72

3 --- 281 193 122 198 135 118 150 50

4 --- 259 196 122 175 131 129 133 ---

5 --- 250 204 95 140 127 134 165 ---

6 --- 251 206 118 130 147 143 183 125

7 223 259 210 114 109 146 160 196 145

8 217 259 212 111 129 137 161 207 ---

9 247 263 217 107 127 159 167 215 ---

10 281 238 229 101 125 116 195 220 ---

11 302 271 232 121 124 115 214 226 ---

12 313 276 235 120 126 115 212 245 ---

13 314 268 231 118 143 113 190 --- ---

14 312 267 223 121 133 115 187 --- 175

15 311 --- 217 123 134 116 212 --- ---

16 312 --- 188 125 139 118 226 139 ---

17 312 241 132 127 144 129 254 76 ---

18 309 239 120 132 95 140 294 130 235

19 --- 239 114 136 110 132 252 139 260

20 --- 241 113 138 111 138 236 --- 299

21 --- 237 111 140 114 149 232 --- 287

22 --- 236 109 142 116 91 236 91 263

23 --- 236 107 143 114 86 233 88 280

24 --- 241 104 145 120 68 245 --- 278

25 --- 253 101 153 116 70 252 126 273

26 --- 268 124 152 121 102 255 141 ---

27 288 275 121 153 114 116 264 143 ---

28 284 265 126 160 116 117 268 155 320

29 299 256 121 173 122 129 271 171 ---

30 --- 221 116 --- 119 132 272 125 259

31 --- 190 114 --- 119 --- 284 --- ---

217 190 101 95 95 68 118 76 50

314 310 235 173 198 159 294 323 320

288 253 164 129 131 121 212 170 214
Appendix 6. Daily mean values for turbidity data at Vache Grasse Creek Site 2 from November 2003 to July 2004.

[Data are in nephlometric turbidity units; ---, missing data]

Day November December January February March April May June July

Minimum

Maximum

Mean

38 Water Quality, Fish Tissue, and Bed Sediment Monitoring in Waterbodies of Fort Chaffee Maneuver Training Center,

Arkansas, 2002-200

1 --- 80 13 20 12 25 --- 55 85

2 --- 40 14 20 9.9 22 --- 60 170

3 --- 13 14 18 9.7 20 50 220 130

4 --- 10 16 18 44 20 37 77 ---

5 --- 8.6 16 200 280 24 34 71 ---

6 --- 5.2 16 120 140 26 33 66 40

7 22 3.5 --- 44 52 --- 33 64 34

8 39 1.7 --- 43 41 13 33 57 ---

9 19 --- --- 37 34 9.8 33 51 ---

10 21 --- 6.6 32 31 130 32 51 ---

11 23 14 6.6 27 28 130 28 67 ---

12 42 13 14 24 26 41 29 52 ---

13 16 19 16 21 22 26 30 --- ---

14 11 12 18 20 22 20 34 --- 20

15 9.1 --- 9.7 19 25 19 51 --- ---

16 7.6 --- 14 18 21 21 29 340 ---

17 9.1 17 120 18 20 21 32 130 ---

18 19 16 88 16 430 22 29 89 15

19 29 12 61 17 110 22 31 86 17

20 16 22 37 17 67 19 31 --- 16

21 18 17 28 15 50 32 30 --- 13

22 19 13 24 13 35 430 27 260 21

23 18 13 22 13 31 300 26 170 40

24 31 12 21 12 33 510 26 --- 33

25 33 11 41 12 40 140 25 --- 25

26 39 8.9 52 11 42 100 24 25 ---

27 58 8.2 47 11 38 70 26 24 ---

28 53 9.3 37 10 40 54 30 23 17

29 14 12 29 11 53 45 32 23 ---

30 20 12 25 --- 60 55 36 140 24

31 --- 14 22 --- 35 --- 81 --- ---

7.6 1.7 6.6 10 9.7 9.8 24 23 13

58 80 120 200 430 510 81 340 170

24 15 30 30 61 82 34 96 44
Justus B.G., and Stanton, G.P.—WATER QUALITY, FISH TISSUE, AND BED SEDIMENT MONITORING IN WATERBODIES OF FORT CHAFFEE 

MANEUVER TRAINING CENTER, ARKANSAS, 2002-2004—U.S. Geological Survey Scientific Investigations Report 2004-5273