U.S. Department of the Interior

U.S. Geological Survey

Scientific Investigations Report 2010–5023

Prepared in cooperation with the City of Wichita, Kansas, 

as part of the Equus Beds Groundwater Recharge Project

Water Quality in the Equus Beds Aquifer and the Little 

Arkansas River Before Implementation of Large-Scale 

Artificial Recharge, South-Central Kansas, 1995–2005

Chloride

plume

Confining clay layer

Confining 

clay layer

Aquifer

recharged

since 1992

Diversion well

(River flow 

captured by 

pumping well)

Recharge

well

Surface-water

treatment

facility

River intake

River intake

Recharge 

water

Earth

berm

Seepage to

groundwater

Permian

 bedrock

Permian

bedrock

Low flow

High flow

Seepage to

groundwater

Recharge

basin

Area of mixing

(forcing back the

chloride plume)

Diversion wells

Waterline

Waterline

Waterline

Waterline

Waterline

Not to scale

Old oil and gas

saltwater pit 

(1930’s–1950’s)

Burrton

Little Arkansas River

N

1940 Water level

 2006 Water level

1992 Water level (maximum 

decline, 65 billion gallons

available for recharge to return

to 1940 water level)

Future recharge

sites (basin

and wells)

Equus Beds Aquifer—Artificial Recharge Process
Cover. Graphic showing the Equus Beds Aquifer artificial recharge process.
Water Quality in the Equus Beds Aquifer 

and the Little Arkansas River Before 

Implementation of Large-Scale Artificial 

Recharge, South-Central Kansas, 1995–

2005

By Andrew C. Ziegler, Cristi V. Hansen, and Daniel A. Finn

Prepared in cooperation with the City of Wichita, Kansas, 

as part of the Equus Beds Groundwater Recharge Project

Scientific Investigations Report 2010–5023

U.S. Department of the Interior

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

KEN SALAZAR, Secretary

U.S. Geological Survey

Marcia K. McNutt, Director

U.S. Geological Survey, Reston, Virginia: 2010

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reproduce any copyrighted materials contained within this report.

Suggested citation:

Ziegler, A.C., Hansen, C.V., and Finn, D.A., 2010, Water quality in the Equus Beds aquifer and the Little Arkansas River 

before implementation of large-scale artificial recharge, south-central Kansas, 1995–2005: U.S. Geological Survey 

Scientific Investigations Report 2010–5023, 143 p. 
iii

Contents

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

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

Background and Description of Study Area ....................................................................................2

Groundwater Recharge Demonstration Project..............................................................................4

Related Water-Quality Studies ...........................................................................................................5

Purpose and Scope ..............................................................................................................................9

Acknowledgments................................................................................................................................9

Methods...........................................................................................................................................................9

Sampling Sites.......................................................................................................................................9

Water-Sample Collection...................................................................................................................12

Discrete Surface and Groundwater-Quality Samples .........................................................12

Continuous Surface-Water-Quality Monitoring....................................................................13

Quality Assurance and Quality Control ...........................................................................................14

Regression Analysis ..........................................................................................................................14

Effective Porosity................................................................................................................................14

Area Calculations................................................................................................................................15

Water Quality of the Equus Beds Aquifer and Little Arkansas River, 1995–2005 ..............................15

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

Specific Conductance...............................................................................................................15

Oxidation-Reduction Potential.................................................................................................23

Major Ions............................................................................................................................................23

Sulfate .........................................................................................................................................23

Chloride........................................................................................................................................32

Nutrients...............................................................................................................................................40

Trace Elements....................................................................................................................................44

Arsenic.........................................................................................................................................44

Iron ...............................................................................................................................................48

Manganese.................................................................................................................................50

Organic Compounds...........................................................................................................................55

Bacterial and Viral Indicators...........................................................................................................56

Total Coliform..............................................................................................................................56

Fecal Coliform.............................................................................................................................57

Escherichia Coli..........................................................................................................................57

Viral Indicators ...........................................................................................................................58

Summary and Conclusions.........................................................................................................................59

Selected References...................................................................................................................................61
iv

Figures

1. Map showing extent of Equus Beds aquifer, area where chloride 

concentrations equal 250 milligrams per liter or more, and location 

of artificial recharge sites and study area near Wichita, south-central 

Kansas ...................................................................................................................................3

2. Graph showing water use for the city of Wichita municipal supply and 

agricultural irrigation, 1941–2005 ......................................................................................5

3–11. Maps showing—

3. Water-level altitudes in Equus Beds aquifer, October 1992 .........................................6

4. Water-level recovery in Equus Beds aquifer in study area, October 1992–

January 2006.........................................................................................................................7

5. Water-level altitudes in Equus Beds aquifer in study area, January 2006.................8

6. Location in and near the study area of (A) surface-water and shallow 

groundwater monitoring sites and (B) surface-water and deep 

groundwater monitoring sites .........................................................................................10

7. Altitude of bedrock surface below Equus Beds aquifer and approximate 

location of bedrock low in study area............................................................................16

8. Estimated effective porosity in study area....................................................................17

9. Average specific conductance in and near the study area, 1995–2005, in 

(A) shallow wells and (B) deep wells .............................................................................24

10. Average oxidation-reduction potential in the study area, 1995–2005, in 

(A) shallow wells and (B) deep wells .............................................................................26

11. Average sulfate concentrations in the study area, 1995–2005, in 

(A) shallow wells and (B) deep wells .............................................................................29

12–13. Graphs showing—

12. Statistical relation between specific conductance and sulfate 

concentrations in (A) shallow index wells, (B) deep index wells, 

and (C) combined shallow and deep index wells.........................................................31

13. Duration curves of computed dissolved chloride concentrations, 1995–

2005, Little Arkansas River near Halstead and near Sedgwick, Kansas ..................33

14–15. Maps showing—

14. Average chloride concentrations in and near the study area, 1982–84,

1989–90, and 1995–2005, for (A) shallow wells and (B) deep wells...........................34

15. Changes in chloride concentrations in the Equus Beds aquifer near 

Burrton, Kansas, during 1939–2005.................................................................................36

16. Graph showing statistical relation between specific conductance and 

chloride concentrations in (A) shallow index wells, (B) deep index wells, 

and (C) combined shallow and deep index wells.........................................................41

17. Map showing average nitrite plus nitrate concentrations in the study 

area, 1995–2005, in (A) shallow wells and (B) deep wells ..........................................42

18. Graph showing duration curves of computed dissolved arsenic 

concentrations, 1995–2005; Little Arkansas River near Halstead and 

near Sedgwick, Kansas ....................................................................................................45

19. Map showing average arsenic concentrations in the study area, 

1995–2005, in (A) shallow wells and (B) deep wells.....................................................46

20. Graph showing statistical relation between oxidation-reduction potential 

and arsenic concentrations in (A) shallow index wells, (B) deep index wells, 

and (C) combined shallow and deep index wells.........................................................49
v

21–22. Maps showing—

21. Average dissolved iron concentrations in the study area, 

1995–2005, in (A) shallow wells and (B) deep wells.....................................................51

22. Average dissolved manganese concentrations in the study area, 

1995–2005, in (A) shallow wells and (B) deep wells.....................................................53

23–25. Graphs showing—

23. Duration curves of computed dissolved atrazine concentrations, 

1999–2005, Little Arkansas River near Halstead and near Sedgwick, 

Kansas .................................................................................................................................56

24. Duration curves of computed fecal coliform bacteria densities,

 1999–2005, Little Arkansas River near Halstead and near Sedgwick, 

Kansas .................................................................................................................................58

25. Duration curves of computed Escherichia coli bacteria, 1999–2005; 

Little Arkansas River near Halstead and near Sedgwick, Kansas ............................59

Tables

1. Summary of selected water-quality data from surface-water samples 

collected from February 1995 through December 2005 as a part of the 

Equus Beds Groundwater Recharge Project, south-central Kansas ................................18

2. Summary of selected water-quality data from groundwater samples 

collected from February 1995 through December 2005 as a part of the 

Equus Beds Groundwater Recharge Project, south-central Kansas ................................19

Appendix

Tables

A1. Data-collection site for the Equus Beds Groundwater Recharge Project, 

south-central Kansas, 1995–2005.............................................................................................66

A2. Detection frequency of various water-quality constituents in blank samples 

collected during 1995–2004 from sites in study area used for this report.........................70

A3. Detection frequency of various water-quality constituents in blank samples 

collected during 1999–2004 from sites in study area used for this report.................................74

A4. Summary of major-ion and nutrient concentrations in water samples collected 

as part of the Equus Beds Groundwater Recharge Project, 1995–2005....................................86

A5. Summary of dissolved trace element concentrations in water samples 

collected as part of the Equus Beds Groundwater Recharge Project during 

1995–2005 ...........................................................................................................................................101

A6. Summary of detections of organic compounds in water samples collected as 

part of the Equus Beds Groundwater Recharge Project during 1995–2005............................116

A7. Summary of bacteria and viral indicator detections and triazine herbicide 

concentrations in water samples collected as part of the Equus Beds 

Groundwater Recharge Project during 1995–2005 .....................................................................127

A8. Summary of radionuclide analysis in water samples collected as part of the 

Equus Beds Groundwater Recharge Project, 1995–2005........................................................137
vi

Figures

A-1–A-3. Graphs showing—

 A-1. Relative percentage differences for replicate samples collected 

during1995–2004 that exceeded 10 percent ................................................................142

 A-2. Detection frequency of various water-quality constituents in blank

samples collected during 1995–2004 from sites in study area used 

for this report ....................................................................................................................143

 A-3. Detection frequency of various water-quality constituents in blank 

samples collected during 1999–2004 from sites in study area used 

for this report ....................................................................................................................143

Conversion Factors and Datums

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

 °F = (1.8×°C)+32

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

 °C = (°F-32)/1.8

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

(NAVD 88) or the National Geodetic Vertical Datum of 1929 (NGVD 29).

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

Altitude, as used in this report, refers to distance above the vertical datum.

Multiply By To obtain

Length

foot (ft) 0.3048 meter (m)

micron (μm) ? inch (in.)

mile (mi) 1.609 kilometer (km)

Area

square mile (mi2

) 2.590 square kilometer (km2) 

Volume

gallon (gal) 0.003785 cubic meter (m3

) 

milliliter (mL) 0.033814 ounce (oz)

million gallons (Mgal) 3,785 cubic meter (m3

)

acre-foot (acre-ft) 0.325851 million gallons (Mgal)

Flow rate

acre-foot per year (acre-ft/yr) 1,233 cubic meter per year (m3

/yr)

cubic foot per second (ft3

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

million gallons per day (Mgal/d) 0.04381 cubic meters per second (m3

/s)

Hydraulic gradient

foot per mile (ft/mi) 0.1894 meter per kilometer (m/km)
vii

ASR aquifer storage and recovery

CFU colony-forming unit

DCP data-collection platform

DWA Drinking-Water Advisory, U.S. Environmental Protection Agency

E. coli Escherichia coli

ELISA enzyme-linked immunosorbent assay

GC/MS gas chromatography/mass spectrometry

GIS geographic information system

GMD2 Equus Beds Groundwater Management District No. 2

HAL Health Advisory Level, U.S. Environmental Protection Agency

KDA-DWR Kansas Department of Agriculture, Division of Water Resources

KDHE Kansas Department of Health and Environment

KWO Kansas Water Office

MCL Maximum Contaminant Level, U.S. Environmental Protection Agency

MCLG Maximum Contaminant Level Goal, U.S. Environmental Protection Agency

(mg/L)/yr milligrams per liter per year

mV millivolt

NTU nephelometric turbidity unit

NWIS National Water Information System, U.S. Geological Survey

ORP oxidation-reduction potential

PVC polyvinyl chloride

QA/QC quality assurance/quality control

R2 coefficient of determination

RMSE root mean square error

SDWR Secondary Drinking-Water Regulation, U.S. Environmental Protection 

Agency

BOR Bureau of Reclamation, U.S. Department of the Interior

USEPA U.S. Environmental Protection Agency

USGS U.S. Geological Survey

Acronyms and Abbreviations Used in This Report

Water-quality constituents described in this report were measured or estimated in milligrams 

per liter (mg/L), micrograms per liter (μg/L), microsiemens per centimeter at 25 degrees Celsius 

(μS/cm), colonies per 100 milliliters (col/100 mL), colony-forming units per 100 milliliters (CFU/100 

mL), plaque forming units per 100 milliliters (pfu/100 mL), and picocuries per liter (pCi/L).
viii
Abstract

Artificial recharge of the Equus Beds aquifer using 

runoff from the Little Arkansas River in south-central Kansas was first proposed in 1956 and was one of many options 

considered by the city of Wichita to preserve its water supply. 

Declining aquifer water levels of as much as 50 feet exacerbated concerns about future water availability and enhanced 

migration of saltwater into the aquifer from past oil and gas 

activities near Burrton and from the Arkansas River. Because 

Wichita changed water-management strategies and decreased 

pumping from the Equus Beds aquifer in 1992, water storage 

in the aquifer recovered by about 50 percent. This recovery is 

the result of increased reliance on Cheney Reservoir for Wichita water supply, decreased aquifer pumping, and larger than 

normal precipitation. Accompanying the water-level recovery, 

the average water-level gradient in the aquifer decreased from 

about 12 feet per mile in 1992 to about 8 feet per mile in January 2006.

An important component of artificial recharge is the 

water quality of the receiving aquifer and the water being 

recharged (source water). Water quality within the Little 

Arkansas River was defined using data from two real-time 

surface-water-quality sites and discrete samples. Water quality 

in the Equus Beds aquifer was defined using sample analyses 

collected at 38 index sites, each with a well completed in the 

shallow and deep parts of the Equus Beds aquifer. In addition, data were collected at diversion well sites, recharge sites, 

background wells, and prototype wells for the aquifer storage 

and recovery project. Samples were analyzed for major ions, 

nutrients, trace metals, radionuclides, organic compounds, and 

bacterial and viral indicators. 

Water-quality constituents of concern for artificial 

recharge are those constituents that frequently (more than 

5 percent of samples) may exceed Federal [U.S. Environmental Protection Agency (USEPA)] and State drinking-water criteria in water samples from the receiving aquifer or in samples 

from the source water. Constituents of concern include major 

ions (sulfate and chloride), nutrients (nitrite plus nitrate), trace 

elements (arsenic, iron, and manganese), organic compounds 

(atrazine), and fecal bacterial indicators. This report describes 

the water quality in the Equus Beds aquifer and the Little 

Arkansas River from 1995 through 2005 before implementation of large-scale recharge activities.

Sulfate concentrations in water samples from the Little 

Arkansas River rarely exceeded Federal secondary drinking 

water regulation (SDWR) of 250 milligrams per liter (mg/L). 

Sulfate concentrations in groundwater were exceeded in about 

18 percent of the wells in the shallow (less than or equal to 

80 feet deep) parts of the aquifer and in about 13 percent of 

the wells in the deep parts the aquifer. Larger sulfate concentrations were associated with parts of the aquifer with the largest water-level declines. Water-quality changes in the Equus

Beds aquifer likely were caused by dewatering and oxidation 

of aquifer material that subsequently resulted in increased 

sulfate concentrations as water levels recovered. 

The primary sources of chloride to the Equus Beds 

aquifer are from past oil and gas activities near Burrton and 

from the Arkansas River. Computed chloride concentrations in 

the Little Arkansas River near Halstead exceeded the Federal 

SDWR of 250 mg/L about 27 percent of the time (primarily during low-flow conditions). Chloride concentrations in 

groundwater exceeded 250 mg/L in about 8 percent or less of 

the study area, primarily near Burrton and along the Arkansas 

River. Chloride in groundwater near Burrton has migrated 

downgradient about 3 miles during the past 40 to 45 years. 

The downward and horizontal migration of the chloride is 

controlled by the hydraulic gradient in the aquifer, dispersion 

of chloride, and discontinuous clay layers that can inhibit 

further downward migration. Chloride in the shallow parts of 

the Equus Beds aquifer migrated less than 0.5 mile during the 

past decade. Migration is slower because of the decrease in the 

hydraulic gradient since 1992. On the basis of these results, 

artificial recharge (especially at depths of 100 to 150 feet) 

could create an effective barrier to saltwater migration. 

Nutrients, such as nitrite plus nitrate (hereinafter referred 

to as nitrate), are a water-quality concern because of the 

predominantly agricultural land use in the 150-square-mile 

study area. All nitrate concentrations in water samples collected at the two surface-water monitoring sites on the Little 

Arkansas River from 1995 through 2005 were less than the 

Federal maximum contaminant level (MCL) of 10 mg/L for 

Water Quality in the Equus Beds Aquifer and the Little 

Arkansas River Before Implementation of Large-Scale 

Artificial Recharge, South-Central Kansas, 1995–2005

By Andrew C. Ziegler, Cristi V. Hansen, and Daniel A. Finn
2 Water Quality in the Equus Beds Aquifer and the Little Arkansas River, South-Central Kansas 

nitrate. Groundwater sampling results indicated that average 

nitrate concentrations exceeding the MCL were detected in 

13 percent of the wells in 9 percent of the shallow parts of the 

aquifer in the study area. Little nitrate is present in the deeper 

parts of the aquifer because of chemical reducing conditions.

Several trace elements frequently exceeded drinkingwater criteria, including arsenic, iron, and manganese. 

Computed arsenic concentrations in the Little Arkansas River 

exceeded the Federal drinking-water MCL of 10 micrograms 

per liter (μg/L) about 14 percent of the time primarily during 

low-flow conditions. In shallow groundwater, average arsenic 

concentrations exceeded the MCL in 10 percent of the wells 

(6 percent of the study area), whereas at depths of more than 

80 feet, average arsenic concentrations exceeded the MCL 

in 34 percent of the wells (35 percent of the study area). 

In the Little Arkansas River, dissolved iron concentrations 

exceeded the Federal SDWR of 300 μg/L in 2 percent of water 

samples, and manganese concentrations exceeded the SDWR 

of 50 μg/L in about half of the samples collected. In shallow 

parts of the aquifer, average iron concentrations exceeded 

the SDWR of 300 μg/L in 44 percent of the study area, and 

average manganese concentrations exceeded the SDWR of 

50 μg/L in 60 percent of the study area. In deep parts of the 

aquifer, average iron concentrations exceeded the SDWR in 

44 percent of the study area, and manganese concentrations 

exceeded the SDWR in 97 percent of the area. 

The areal distribution of larger dissolved arsenic, iron, 

and manganese concentrations were similar. Larger naturallyoccurring concentrations of arsenic, iron, and manganese in 

groundwater are associated with more reducing conditions, 

areas where more clay is present in the aquifer material, 

and areas that had large water-level declines and subsequent 

recovery. Effects of artificial recharge on natural dissolved 

concentrations of arsenic in the aquifer potentially can be 

minimized by maintaining the oxidation-reduction potential 

as near 1995–2005 baseline conditions as possible. However, 

in many areas of the aquifer, especially the deeper parts, the 

natural geochemical conditions are conducive to large arsenic 

concentrations. It may be possible to use artificial recharge of 

oxygenated water to create a less reducing geochemical environment, decreasing some of the arsenic and iron dissolved in 

the water, potentially improving the overall water quality in 

the aquifer.

Atrazine was the most commonly detected organic 

compound in the study area. The Federal MCL for atrazine in 

drinking water is 3 mg/L an annual average. Computed concentrations of atrazine in the Little Arkansas River exceeded 

the Federal MCL value of 3.0 mg/L about 27 percent of the 

time, mostly during the late spring to early fall. Atrazine was 

detected in about 55 percent of the samples collected from 

shallow wells, which indicates infiltration from field applications to the shallow groundwater, but concentrations were 

much less than the MCL. 

Large concentrations of coliform bacterial indicators 

(total coliform, fecal coliform, and Escherichia coli) were 

detected in all water samples from the Little Arkansas River. 

These large bacterial indicator densities are typical in central 

and eastern Kansas streams, especially during runoff conditions. Total coliform detections exceeded the USEPA Federal 

Maximum Contaminant Level Goal (MCLG) of 0 colonies 

in water samples from 95 percent of the shallow index wells 

and in 87 percent of the deep wells in the Equus Beds aquifer. 

Many of these detections were in the first samples collected 

from the wells after they were developed, indicating that 

at least some of these detections may be related to drilling. 

Almost all wells sampled for this study had at least 1 sample 

with a total coliform detection; however, the median densities 

for most of these wells were less than 1 colony per 100 milliliter (col./100 mL). Viral indicators (Clostridium perfringens

and E. coli coliphage) were present in samples from the Little 

Arkansas River during storm runoff but were not detected in 

any samples of groundwater. These data indicated that natural 

infiltration of water through the soil removes most bacterial 

and viral indicator organisms. 

Water quality in surface water and groundwater is controlled by the geology of the underlying bedrock and aquifer 

materials, the hydraulic permeability (porosity) and geochemical (oxidation and reduction) properties of the aquifer, and 

the effects of humans related to past oil and gas activities and 

agriculture. When the proposed full-scale artificial recharge of 

the Equus Beds aquifer is implemented, changes in concentrations of water-quality constituents are expected. The increased 

water levels from artificial recharge are expected to slow 

the saltwater migration from the northwest and south of the 

study area, potentially limiting further chloride migration and 

improving the quality of water in the aquifer. Continued monitoring and interpretation of these recharge water-quality data 

relative to drinking-water criteria will help ensure the usable 

quality of water in the Equus Beds aquifer. 

Introduction

Background and Description of Study Area

The study area encompasses approximately 150 square 

miles (mi2) in south-central Kansas, northwest of Wichita 

in Harvey and Sedgwick Counties. The area is bounded by 

the Arkansas River on the southwest and includes the Little 

Arkansas River on the northeast (fig. 1). The Little Arkansas 

River drains an area of about 1,200 mi2 of primarily agricultural land. Crops produced include corn, sorghum, soybeans, 

and wheat. Common agricultural chemicals applied to these 

crops include fertilizers and herbicides, such as alachlor and 

atrazine. Livestock raised in the area include cattle and hogs 

(Kansas Department of Agriculture, 2006). 

The study area is underlain by the Equus Beds aquifer, 

considered a part of the larger High Plains aquifer (fig. 1). The 

aquifer is named for Pleistocene horse fossils in the aquifer 

sediments. Equus is latin for horse. The Equus Beds aquifer 
Introduction 3

0 10 KILOMETERS

0 2 4 6 8 10 MILES

2 4 6 8

MCPHERSON COUNTY

RICE

COUNTY

RENO COUNTY

KINGMAN COUNTY SEDGWICK COUNTY

HARVEY COUNTY

MARION

COUNTY

Study area including Wichita Equus Beds

 well field

Area where chloride concentration equals

 250 milligrams per liter or more

Equus Beds aquifer

EXPLANATION

Approximate 

extent of High

Plains aquifer

in Kansas

Index map

KANSAS

Area 

shown 

on map

Base from U.S. Geological Survey digital data, 1:100,000, 1983

Universal Transverse Mercator projection,

Zone 14

Horizontal coordinate information is referenced to the North American

 Datum of 1983 (NAD 83)

Approximate boundary of

Equus Beds aquifer

(Juracek and Hansen, 1995)

Boundary of chloride concentration equal to or

 greater than 250 milligrams per liter—Dashed 

 where extent is unknown

Artificial recharge site

Boundary of 

Groundwater 

Management 

L

District No. 2 ittle Arkansas River

West Emma Creek

East Emma Creek

Arkansas River

Ninnescah River North Fork

Sand

Creek Creek Em

mae

Turkey

Creek

Kisiwa Creek

Burrton Oil-Field Area 

and 

Intensive Groundwater Use 

Control Area

97°50' 40' 30' 97°20'

38°20'

37°40'

38°

10'

50'

Wichita

Andale

Haven

Hutchinson

South

Hutchinson

Valley Center

Maize Colwich

Goddard

Bentley

Sedgwick

Halstead

Hesston

Goessel

Windom

Lehigh Canton Galva McPherson

Moundridge

Buhler

Alta Mills

Inman

Newton

North

Newton

Park

City

Cheney

Reservoir

Mount

Hope

Burrton

Figure 1. Extent of Equus Beds aquifer, area where chloride concentrations equal 250 milligrams per liter or more, and location of 

artificial recharge sites and study area near Wichita, south-central Kansas.
4 Water Quality in the Equus Beds Aquifer and the Little Arkansas River, South-Central Kansas 

[about 300 feet (ft) thick] consists of alluvial deposits of sand 

and gravel interbedded with clay or silt and is an important 

source of groundwater because of the good water quality, 

shallow depth to the water table, and large saturated thickness (Williams and Lohman, 1949). The general direction of 

groundwater movement within the study area is to the eastnortheast (Aucott and others, 1998) except where the hydraulic gradient is altered by pumping wells and near a low-head 

dam on the Little Arkansas River at Halstead. 

The well field developed by the city of Wichita in the 

Equus Beds aquifer during the 1940s and 1950s is one of 

the primary sources of water for the city and the surrounding area. As of 2005, there were 55 active city public-supply 

wells in the Wichita Equus Beds well field within the study 

area. Numerous irrigation wells also withdraw water from the 

aquifer within the boundaries of Groundwater Management 

District No. 2 (GMD2) (Equus Beds Groundwater Management District No. 2, 1990) (fig. 1).

The city of Wichita began using water from Cheney 

Reservoir (fig. 1) in 1965 to supplement its supply from the 

Equus Beds aquifer. Water use by the city of Wichita and 

irrigation withdrawals are illustrated in figure 2. The proportion of the water supply obtained from Cheney Reservoir 

increased from 20 percent in 1965 to 44 percent in 1994. From 

1995 through 2005, water from Cheney Reservoir ranged from 

51 to 69 percent of Wichita’s water supply. The increased 

reliance on surface water from Cheney Reservoir was part of 

Wichita’s Integrated Local Water Supply Plan implemented in 

1993 (Warren and others, 1995; city of Wichita, written commun., 2000). This plan was initiated to ensure that the city’s 

water-supply needs are met through 2050 by promoting conservation, increasing water use from Cheney Reservoir, and 

decreasing pumping from city wells in Wichita Equus Beds 

well field. The plan also calls for investigating the Equus Beds 

aquifer storage and recovery (ASR) using excess water from 

the Little Arkansas River. As the population in the Wichita 

area increases, demands for water could exceed existing supplies as early as 2050 if no additional water supply is acquired 

(Jerry Blain, city of Wichita, oral commun., 2005).

Substantial water-level declines in the Equus Beds aquifer have resulted from pumping groundwater for agricultural 

and municipal needs, as well as periodic drought conditions. 

The lowest water levels to date were recorded in October 

1992 (fig. 3) and were as much as 50 ft lower than the predevelopment (1940) water levels in some locations (Hansen 

and Aucott, 2001, 2004; Hansen, 2007). Water-level declines 

caused concern about the adequacy of the city’s future water 

supply. Another concern is saltwater migration into the aquifer. 

Sources of saltwater include the Arkansas River, oil-field 

brines that leaked from surface disposal pits or injection 

wells in the Burrton oil-field area northwest of the study area 

(fig. 1), municipal wastewater facility discharges, and mineralized water from the underlying Wellington Formation (Ziegler 

and others, 1999; Whittemore, 2007). 

Groundwater levels in the aquifer increased by more than 

20 ft in some areas by January 2006 compared to 1992 levels 

(fig. 4). Water storage increased by about 50 percent since 

1992 because of natural recharge of larger than normal precipitation, increased reliance on Cheney Reservoir for Wichita 

water supply, and decreased aquifer pumping (Hansen, 2007). 

Accompanying the water-level recovery, the water-level gradient in the aquifer decreased from about 12 feet per mile (ft/mi) 

in 1992 to about 8 ft/mi in January 2006. Other factors contributing to water-level increases include subsurface inflow, 

streamflow losses, and irrigation return flow (Myers and 

others, 1996). Groundwater levels in the study area in January 

2006 are shown in figure 5.

Groundwater Recharge Demonstration Project

In 1956, Stramel (1956, 1962a, b, 1967) proposed the 

artificial recharge of the Equus Beds groundwater reservoir by 

recharging the aquifer with runoff during periods of abundant 

precipitation. This artificially recharged water then could 

be recovered by pumping from the aquifer during periods 

of drought. Stramel proposed using a variety of techniques 

including water spreading, recharge pits or ponds, recharge 

wells, and induced recharge by pumping. He also suggested 

investigation of the relation between streamflow or stage and 

water quality for the Arkansas River, Little Arkansas River, 

and Kisiwa Creek as sources for artificial recharge. Of these 

streams, the Little Arkansas River had the best known water 

quality.

The Equus Beds Groundwater Recharge Demonstration 

Project began in 1995 to test artificial recharge as a method 

for increasing water supply and preventing water-quality 

degradation (Ziegler and others, 1999). The purpose of the 

demonstration project was to investigate the feasibility of 

artificial recharge and its effects on the water quantity and 

quality of the Equus Beds aquifer. The project was a cooperative effort between the city of Wichita, the U.S. Geological 

Survey (USGS), and the Bureau of Reclamation (BOR, U.S. 

Department of the Interior), with additional participation from 

the Equus Beds GMD2 and the U.S. Environmental Protection 

Agency (USEPA). The USGS roles in the cooperative study 

were to document changes in hydrologic and water-quality 

conditions in the study area, to identify the probable causes of 

the changes, and to develop a baseline condition for evaluating the effects of larger full-scale artificial recharge. Project 

work was coordinated with the Kansas Department of Health 

and Environment (KDHE), the Kansas Water Office (KWO), 

and the Kansas Department of Agriculture, Division of Water 

Resources (KDA-DWR). Burns and McDonnell Engineering 

Consultants (Kansas City, Missouri) and Mid-Kansas Engineering Consultants (Wichita, Kansas) provided engineering 

expertise and project management. The construction, maintenance, and operation of the recharge facilities were performed 

by the city of Wichita.

Recharge sites were constructed near the towns of 

Halstead and Sedgwick (fig. 1) to divert water from the Little 

Arkansas River for the recharge demonstration project (Ziegler 
Introduction 5

and others, 1999; Schmidt and others, 2007). At each site, 

water from the river was diverted when streamflow exceeded 

base-flow requirements established by KDA-DWR permit 

conditions. Different methods of diverting river water and 

recharging the aquifer were used at each site. At the Halstead 

diversion site, water could be pumped from a well adjacent 

to the Little Arkansas River when streamflow exceeded 42 

cubic feet per second (ft3/s) (minimum streamflow requirement 

established by KDA-DWA) from April 1 through September 

30, and 20 ft3/s from October 1 through March 31 (Burns and 

McDonnell, 1996). This water was recharged to the aquifer through recharge basins, trench, or injection well at the 

Halstead recharge site. The recharge activity continued from 

May 1997 to June 2002. During this time, the number of days 

per year that minimum streamflow requirements in the Little 

Arkansas River were large enough to allow withdrawal of 

water for recharge from the well adjacent to the Little Arkansas River ranged from 99 days in 2002 to 349 days in 1999 

(http://ks.water.usgs.gov/studies/equus/equus_hilites.html).

At the Sedgwick recharge site, water can be withdrawn 

directly from the Little Arkansas River when streamflow 

exceeded 40 ft3

/s (minimum streamflow requirement) regardless of season. This water was treated to decrease turbidity and total fecal coliform bacteria, and to remove organic 

compounds prior to being recharged to the aquifer through 

recharge basins. Recharge activities at the Sedgwick site 

continued from April 1998 to November 2000. During this 

time, the number of days per year that minimum flow requirements in the Little Arkansas River were large enough to allow 

withdrawal of recharge water from the river ranged from a 

low of 290 days in 2000 to a high of 365 days in 1999 (http://

ks.water.usgs.gov/studies/equus/equus_hilites.html).

Water samples were collected by USGS personnel from 

the Little Arkansas River and from numerous wells in the 

study area. These water samples were analyzed for dissolved 

solids, total and dissolved inorganic constituents, nutrients, 

organic and volatile organic compounds, radionuclides, 

and bacterial indicators (Ziegler and others, 1999). Primary 

constituents of concern for artificial recharge were sodium, 

chloride, nitrite plus nitrate (hereinafter referred to as nitrate), 

iron, manganese, atrazine, and total coliform bacteria. Constituents of concern were defined as those constituents with 

concentrations exceeding 20 percent of the USEPA established 

Federal drinking-water criteria (Ziegler and others, 1999). 

Chloride and atrazine were of particular concern because 

concentrations of these constituents in the Little Arkansas 

River frequently exceeded the Federal SDWR for chloride and 

the Federal MCL value for atrazine established by the USEPA 

(Ziegler and others, 1999). The Federal MCL for atrazine in 

drinking water is 3 μg/L an annual average. Arsenic was added 

to the constituents of concern list (Ziegler and others, 2001) 

because in 2001 USEPA lowered the arsenic MCL from 50 to 

10 μg/L (micrograms per liter) effective January 2006 (U.S. 

Environmental Protection Agency, 2001b). In this report, 

sodium is not discussed in detail because the USEPA drinkingwater equivalence level is an advisory recommended dietary 

level.

Related Water-Quality Studies

Ziegler and others (1999) described the baseline water 

quality (1995–98) and preliminary effects of artificial recharge 

on the water quality of the Equus Beds aquifer. The report 

indicated that the initial effects of artificial recharge were minimal, that the recharge and aquifer water types were compatible, and that sodium, chloride, nitrate, iron, manganese, atrazine, and total coliform bacteria were constituents of concern. 

Concentrations of chloride and atrazine in water from some 

wells increased minimally after the artificial recharge project 

began to concentrations approximating the recharge water 

concentrations. However, these concentrations were within the 

variance of baseline concentrations in the aquifer and considerably less than the USEPA Federal SDWR and MCL. Ziegler 

and others (2001) reported that the overall effects of 3 years of 

recharge did not substantially change groundwater quality. 

80,000

0

20,000

40,000

60,000

WATER USE, IN ACRE-FEET PER YEAR

Total city water use

for public supply Permitted groundwater use

for agricultural irrigation, 2006

City groundwater use

for public supply 

City surface-water use from

Cheney Reservoir for public

supply

Estimated groundwater

use for agricultural irrigation

19401950196019701980199020002005

Figure 2. Water use for the city of Wichita municipal supply and agricultural irrigation, 1941–2005 (modified from Hansen, 2007).
6 Water Quality in the Equus Beds Aquifer and the Little Arkansas River, South-Central Kansas 

Wichita

Newton

Halstead

Maize

Sedgwick

Colwich

Mount Hope

Burrton

Andale

Hesston

Boundary of study area

0 1 2 3 4 5 MILES

0 1 2 3 4 5 KILOMETERS

Base from U.S. Geological Survey digital data, 1:100,000, 1983

Universal Transverse Mercator projection,

Zone 14

Horizontal coordinate information is referenced to the North American

 Datum of 1983 (NAD 83)

97°40'

38°

38°50’

38°05’

55’

35' 30' 97°25'

Little Arkansas River

West Em

ma Creek

Middle Emma Creek

East Emma Creek

Em

ma Creek

Sand Creek

Jester Creek

Valley

L

Center ittle Arkansas River

ARKANSAS

RIVER

Kisiwa Creek

Big Slough

Cowskin Creek

R. 3 W. R. 2 W. R. 1 W.

T.

26

S.

T.

25

S.

T.

24

S.

T.

23

S.

T.

22

S.

R. 4 W.

EXPLANATION

RENO COUNTY

SEDGWICK COUNTY

HARVEY COUNTY

1,440

1,435

1,430

1,425

1,420

1,415

1,440

1,435

1,430

1,425

1,420

1,415

1,410

1,405

1,400

1,395

1,390

1,380

1,445

1,410

1,405

1,400

1,395

1,390

1,385

1,375

1,370

1,360

1,355

1355

1,350

1,345

1,345

1,355

1350

1,360

1,365

1,370

1,375

1,385

1,340

1,340

1,335

1,365

1,380

Bentley

Study area

Water-level contour—Shows altitude of water

 level, October 1992. Dashed where approximately

 located. Contour interval 5 feet. Datum is National

 Geodetic Vertical Datum of 1929

Approximate location of bedrock low

 (McPherson channel)

Approximate direction of groundwater flow

U.S. Geological Survey streamflow-gaging station

Equus beds historic observation well

Water-level measurements were made by city of Wichita personnel

1,355

Black

Kettle Creek

Boundary of study area

Figure 3. Water-level altitudes in Equus Beds aquifer, October 1992 (modified from Hansen and Aucott, 2001).
Introduction 7

Wichita

Newton

Maize

Sedgwick

Colwich

Mount Hope

Burrton

Andale

Hesston

+8

+6

+4 +2

+24

+22

+18

+20 +16

0 1 2 3 4 5 MILES

0 1 2 3 4 5 KILOMETERS

Base from U.S. Geological Survey digital data, 1:100,000, 1983

Universal Transverse Mercator projection,

Zone 14

Horizontal coordinate information is referenced to the North American

 Datum of 1983 (NAD 83)

97°40'

38°

38°50’

38°05’

55’

35' 30' 97°25'

Little Arkansas River

West Em

ma Creek

Middle Emma Creek

East Emma Creek

Em

ma Creek

Sand Creek

Jester Creek

Valley

Center

Little Arkansas River

ARKANSAS

RIVER

Big Slough

R. 3 W. R. 2 W. R. 1 W.

T.

26

S.

T.

25

S.

T.

24

S.

T.

23

S.

T.

22

S.

R. 4 W.

EXPLANATION

SEDGWICK COUNTY

HARVEY COUNTY

Bentley

Halstead

RENO COUNTY

+12

+14

+16

+4

+6

+8

+2

+10

+12

+8+6

+14

+4

0

+16

+18

+26

+28

+24

+12

+2

+2

+4

+4

+6

+8

+6

+8

+12

+12

+14

+16

+18

+2

+22

+20

+10

Kisiwa Creek

+10

+10

+14

Study area

Area of water-level recovery between:

+10 and +20 feet

+20 and +30 feet

Line of equal water-level change—

 Interval 2 feet

U.S. Geological Survey streamflow-gaging station

Equus beds historic observation well

Water-level measurements were made by city of Wichita personnel

+12

Boundary of study area

Black Kettle Creek Boundary of study area

Cowskin Creek

Figure 4. Water-level recovery in Equus Beds aquifer in study area, October 1992–January 2006 (modified 

from Hansen, 2007).
8 Water Quality in the Equus Beds Aquifer and the Little Arkansas River, South-Central Kansas 

Wichita

Newton

Maize

Sedgwick

Colwich

Mount Hope

Burrton

Andale

Hesston

Base from U.S. Geological Survey digital data, 1:100,000, 1983

Universal Transverse Mercator projection,

Zone 14

Horizontal coordinate information is referenced to the North American

 Datum of 1983 (NAD 83)

97°40'

38°

38°50’

38°05’

55’

35' 30' 97°25'

Little Arkansas River

West Em

ma Creek

Middle Emma Creek

East Emma Creek

Em

ma Creek

Sand Creek

Jester Creek

Valley

Center Little Arkansas Rive

AR

r

KANSAS

RIVER

Kisiwa Creek

Big Slough

R. 3 W. R. 2 W. R. 1 W.

T.

26

S.

T.

25

S.

T.

24

S.

T.

23

S.

T.

22

S.

R. 4 W.

EXPLANATION

RENO COUNTY

SEDGWICK COUNTY

HARVEY COUNTY

1,440

1,435

1,430

1,425

1,440

1,435

1,430

1,425

1,405

1,400

1,395

1,390

1,380

1,445

1,420

1,415

1,410

1,405

1,400

1,395

1,390

1,385

1,375

1,370

1,360

1,355

1,350

1,345

1,345

1,340

1,350

1,355

1,360

1,365

1,370

1,375

1,385

1,340

1,335

1,335

1,365

1,380

Bentley

Study area

Water-level contour—Shows altitude of water

 level, January 2006. Dashed where approximately

 located. Contour interval 5 feet. Datum is North

 American Vertical Datum of 1988

Approximate location of bedrock low

(McPherson channel)

Approximate direction of groundwater flow

U.S. Geological Survey streamflow-gaging station

Index well and site identifier

Equus beds historic observation well

Water-level measurements in wells were made by city of 

Wichita and Equus Beds Groundwater Management

District No. 2 personnel. Water-level measurements at

gaging stations were collected by U.S. Geological Survey.

1,355

IW-38A

IW-37A

IW-37A

IW-35A IW-36A

IW-34A

IW-33A

IW-32A

IW-30A IW-31A

IW-29A

IW-28A

IW-26A

IW-24A IW-25A

IW-23A

IW-22A

IW-21A

IW-27A

IW-20A

IW-19A

IW-18A

IW-15A IW-16A IW-17A

IW-14A

IW-09A IW-10A

IW-08A

IW-13A

IW-07A

IW-05A IW-06A

IW-04C

IW-03A

IW-02C

IW-01C

IW-11A-2

IW-12A

Black

Kettle Creek

1,330

Halstead

1,420

1,415

1,410

Boundary of study area

Boundary of study area

0 1 2 3 4 5 MILES

0 1 2 3 4 5 KILOMETERS

Cowskin Creek

Figure 5. Water-level altitudes in Equus Beds aquifer in study area, January 2006 (modified from Hansen, 2007).
Methods 9

Schmidt and others (2007) presented the results from a 

simple mixing model using chloride as a tracer that indicated 

that the water in shallow (less than 80 ft) monitoring wells 

adjacent to the Little Arkansas River was 80 percent stream 

water. The mixing model also indicated that about 25 percent 

of the pumping well water at Halstead was from the shallow 

part of the aquifer. 

Christensen and others (2000, 2003) developed sitespecific regression models to relate constituent concentrations 

from laboratory-analyzed samples to continuous in-stream 

sensor measurements by plotting each explanatory variable 

against the response variable. Regression models were developed on the basis of physical properties and water-quality 

analyses of water samples collected from 1995 through 2002. 

These models were used to compute alkalinity, dissolved 

solids, total suspended solids, sulfate, chloride, arsenic, and 

atrazine concentrations, and fecal coliform bacteria densities 

(Christensen and others, 2000, 2003). Computed water-quality 

data were compared to measured data to determine errors and 

limitations of the regression models. Differences between 

computed data and laboratory results were less than 25 percent 

for alkalinity, dissolved solids, sulfate, and chloride concentrations and more than 25 percent for total suspended solids, 

arsenic, and atrazine concentrations, and bacteria densities 

(Christensen and others, 2000). The use of these models eliminates the wait for laboratory analyses and provides continuous 

hourly computations of constituent concentrations and loads. 

These computed concentrations and loads are available on the 

World Wide Web for the two Little Arkansas River surfacewater monitoring sites at http://nrtwq.usgs.gov/ks/. 

Purpose and Scope

The purpose of this report is to describe the water quality 

in the Equus Beds aquifer and the Little Arkansas River from 

1995 through 2005, before implementation of large-scale 

[design capacity of 100 million gallons per day (Mgal/d)] 

recharge activities (Kansas Underground Injection Control 

Area Permit Class V Injection Well, Kansas Permit No. KS-05-

079-001). This report includes water-quality data collected 

from 1995 through 2005. The study described herein is part of 

a long-term cooperative study (since 1940) between the city of 

Wichita and USGS to describe the water quantity and quality 

conditions in the Equus Beds aquifer and the Little Arkansas River and more recently, the potential effects of artificial 

recharge on water resources in south-central Kansas. This 

description of water-quality conditions serves as a baseline 

to detect any subsequent changes in the water quality in the 

Equus Beds aquifer and the Little Arkansas River. 

The quality of water was assessed through laboratory 

analysis of water samples collected at two surface-water monitoring sites on the Little Arkansas River and from a network 

of monitoring wells in shallow and deep parts of the aquifer. 

Additional water-quality determinations were made from continuous regression-model computations for chloride, arsenic, 

and atrazine concentrations and fecal bacterial indicators in the 

Little Arkansas River (Christensen and others, 2000). Waterquality constituents discussed in this report include those 

listed in the primary and secondary USEPA Federal drinkingwater criteria, as well as onsite measurements such as specific 

conductance and oxidation-reduction potential (ORP), that are 

used in the interpretation of water-quality data. Maps showing 

average concentrations of constituents illustrate their distribution in groundwater throughout the study area for shallow and 

deep parts of the aquifer. 

Acknowledgments

The authors acknowledge the invaluable assistance of 

several city of Wichita, Groundwater Management District 

2 personnel, and USGS employees working on this study. 

Technical colleague reviews by Dale Blevins (USGS), 

Brenda Smith (USGS), and Jerry Blain and Deb Ary (city 

of Wichita) contributed to improved technical and editorial 

clarity of the report. Trudy Bennett and Allen Bewsher of the 

USGS Kansas Water Science Center collected water samples, 

measured water levels, and maintained automated equipment 

at the monitoring sites. Joan Kenny, Heather Ross Schmidt, 

and Myrna Gouw (all USGS personnel) assisted with early 

drafts of the text, tables, and illustrations. Deneise Schneider 

(USGS) performed data entry, database maintenance, and 

quality assurance. Appreciation is expressed for “P” and “EB” 

well data from GMD2 managers Mike Dealy and Tim Boese. 

Terryl Pajor, Vernon Strasser, and laboratory staff for the city 

of Wichita Municipal Water and Wastewater Laboratory conducted laboratory analyses. And lastly, many thanks to David 

Warren, Wichita Director of Utilities, and Jerry Blain, Water 

Supply Projects Administrator and Superintendent of pumping 

and production, city of Wichita Water and Sewer Department, 

who led the overall study design and provided invaluable 

technical input for all of the published reports associated with 

the study.

Methods

Sampling Sites

Streamflow, water-level, and water-quality data were 

collected from the Little Arkansas River and from the Equus

Beds aquifer before, during, and after the artificial recharge 

demonstration project to evaluate the effects of artificially 

recharging surface water into the aquifer. Data-collection sites 

used to describe water quality in the Little Arkansas River 

and in the Equus Beds aquifer for this report are listed in table 

A-1 in the Appendix (at the back of this report). Locations 

of the surface-water sites and monitoring wells are shown in 

figures 6A and 6B. Well data for “EB” and “P” wells are not 
10 Water Quality in the Equus Beds Aquifer and the Little Arkansas River, South-Central Kansas 

Wichita

Newton

Maize

Sedgwick

Colwich

Mount Hope

Burrton

Andale

Hesston

0 1 2 3 4 5 MILES

0 1 2 3 4 5 KILOMETERS

EB-22A

Base from U.S. Geological Survey digital data, 1:100,000, 1983

Universal Transverse Mercator projection,

Zone 14

Horizontal coordinate information is referenced to the North American

 Datum of 1983 (NAD 83)

97°40'

38°

38°50’

38°05’

55’

35' 30' 97°25'

Little Arkansas River

West Em

ma Creek

Middle Emma Creek

East Emma Creek

Em

ma Creek

Sand Creek

Jester Creek

Valley

Center

Little Arkansas River

Kisiwa Creek

Big Slough

R. 3 W. R. 2 W. R. 1 W.

T.

26

S.

T.

25

S.

T.

24

S.

T.

23

S.

T.

22

S.

R. 4 W.

EXPLANATION

RENO COUNTY SEDGWICK COUNTY

HARVEY COUNTY

Bentley

U.S. Geological Survey streamflow-

 gaging station, continuous real-time

 water-quality monitoring site and

 site identifier

Index well and site identifier

Phase I recharge well (RRW) or 

 basin (RB) and site identifier

Recharge demonstration site and 

 site identifier

Study area

Background well and site identifier

“EB” well and site identifier

“P” well and site identifier

IW-38A

IW-37A

IW-37A

IW-35A IW-36A

IW-34A

IW-33A

IW-32A

IW-30A IW-31A

IW-28A IW-29A

IW-26A

IW-24A IW-25A

IW-23A

IW-22A

IW-21A

IW-27A

IW-19A IW-20A

IW-18A

IW-15A IW-16A IW-17A

IW-14A

IW-08A IW-09A IW-10A

IW-13A

IW-07A

IW-05A IW-06A

IW-04A

IW-02A IW-03A

IW-01A

IW-11A-2

IW-12A

Black

Kettle Creek

Halstead

P-35

P-35

P-34

P-32

P-30

P-28

P-27

P-26

P-31

P-29

EB-9A

EB-8A

EB-5A

EB-2A

EB-56A

EB-20A

EB-19A

EB-18A

EB-18A

EB-17A

EB-15A

EB-14A

EB-13A

EB-12A

EB-11A

EB-10A

EB-58A

EB-44A

EB-43A

EB-1AA

EB-57A

EB-4AA EB-16A

EB-3AA

EB-7A RB-2

RB-2

RB-1

RRW-3

RRW-4

RRW-2

RRW-1

TH-12-95

TH-10-95

TH-06-95

TH-02-95

ALTA MILLS

EB-142-A3

SEDGWICK WELL

07144100

07143672

07144100

TH-08-A5, A4, A3, A2, A1

CITY WELL-SEDGWICK

SMW-H14

SMW-H4 EB-145-A5

SMW-S11

SMW-S11

SMW-S13

EB-145-A4, A3, A2, A1

TH-12-95

ARKANSAS RIVER

Boundary of study area

Boundary of study area

Cowskin Creek

A. Shallow wells

Surface-water monitoring site

Shallow groundwater monitoring sites

Figure 6. Location in and near the study area of (A) surface-water and shallow groundwater monitoring sites and (B) surfacewater and deep groundwater monitoring sites.
Methods 11

Wichita

Newton

Maize

Sedgwick

Colwich

Mount Hope

Andale

Hesston

DW-TW-02

0 1 2 3 4 5 MILES

0 1 2 3 4 5 KILOMETERS

Base from U.S. Geological Survey digital data, 1:100,000, 1983

Universal Transverse Mercator projection,

Zone 14

Horizontal coordinate information is referenced to the North American

 Datum of 1983 (NAD 83)

97°40'

38°

38°50’

38°05’

55’

35' 30' 97°25'

Little Arkansas River

West Em

ma Creek

Middle Emma Creek

East Emma Creek

Em

ma Creek

Sand Creek

Jester Creek

Valley

Center

Little Arkansas River

Kisiwa Creek

Big Slough

R. 3 W. R. 2 W. R. 1 W.

T.

26

S.

T.

25

S.

T.

24

S.

T.

23

S.

T.

22

S.

R. 4 W.

RENO COUNTY SEDGWICK COUNTY

HARVEY COUNTY

Bentley

IW-38C

IW-35C IW-36C IW-37C

IW-34C

IW-33C

IW-32C

IW-30C IW-31C

IW-28C IW-29C

IW-26C

IW-24C IW-25C

IW-21C IW-22C IW-23C

IW-27C

IW-20C IW-19C

IW-18C

IW-15C IW-16C IW-17C

IW-14C

IW-09C IW-10C IW-08C

IW-13C

IW-07C

IW-06C IW-05C

IW-04C

IW-02C

IW-01C

IW-11C

IW-12C

Black

Kettle Creek

Halstead

07144100

07143672

ARKANSAS RIVER

RB-2

RB-1

RRW-3

RRW-4

RRW-2

RRW-1

EB-145-P-D5

DMW-S14

DMW-H13

DMW-H1

DMW-S10

RRW-03

RRW-02

RRW-01

EB-9C

EB-8C

EB-7C

EB-5B

EB-2C

EB-56C

EB-32B EB-22B

EB-21A

EB-20B

EB-18C

EB-17C

EB-15C

EB-14C

EB-13C

EB-12C

EB-11C

EB-10C

P-35A

P-34A

P-32A

P-30A

P-28A

P-27A

P-26A

DW-TW-09, 08 DW-TW-07, 06

DW-TW-05, 04, 03

DW-TW-02, 01

EB-1B

EB-58C

EB-44C

EB-43C

EB-3B

P-31A

P-29A

EB-4B

EB-57B

EB-16C

Burrton

IW-03C

Boundary of study area

Boundary of study area

Cowskin Creek

B. Deep wells

HALSTEAD DIVERSION SITE

EXPLANATION

U.S. Geological Survey streamflow-

 gaging station, continuous real-time

 water-quality monitoring site and

 site identifier

Index well and site identifier

Phase I recharge well (RRW) or 

 basin (RB) and site identifier

Recharge demonstration site and 

 site identifier

Study area

Artificial storage and recovery 

 prototype well and site identifier

“EB” well and site identifier

“P” well and site identifier

IW-37C

P-35A

EB-18C RB-2

07144100

DMW-S10

Surface-water monitoring site

Deep groundwater monitoring sites

Figure 6. Location in and near the study area of (A) surface-water and shallow groundwater monitoring sites and (B) surfacewater and deep groundwater monitoring sites.—Continued
12 Water Quality in the Equus Beds Aquifer and the Little Arkansas River, South-Central Kansas 

provided in table A-1, but are available through GMD2 (Mike 

Dealy, Manager, written communication, 2006). Surface-water 

samples were collected at USGS streamflow-gaging stations 

on the Little Arkansas River at Highway 50 near Halstead (site 

07143672) and near Sedgwick (site 07144100). These two 

stations also are continuous real-time water-quality monitoring 

sites. 

Monitoring wells discussed in this report were divided 

into two groups by depth to describe differences in the water 

quality of shallow and deep parts of the Equus Beds aquifer 

within the study area. For the purposes of this report, shallow wells were completed and screened at depths below land 

surface that were equal to or less than 80 ft and were open 

to the shallow part of the Equus Bed aquifer (fig. 6A). Deep 

wells (fig. 6B) were screened at depths of more than 80 ft deep 

and were completed in deep parts of the aquifer. All monitoring wells were constructed of polyvinyl chloride (PVC) pipe 

and typically are screened in the lowermost 10 to 20 ft of the 

casing (table A-1). Table A-1 provides information for the 

sites sampled for this study and groupings and subgroupings 

of these sites. The GMD2 “EB” and “P” well data (not listed 

in table A-1) also were used to describe the distribution of 

specific conductance and chloride concentrations and also 

were grouped into shallow and deep wells on the basis of well 

depths (figs. 6A and 6B). These data are available through 

GMD2 (Mike Dealy, Manager, written communication, 2006).

Some of the monitoring sites are located in areas where 

water either was diverted for artificial recharge or was 

recharged into the Equus Beds aquifer as part of the recharge 

demonstration project and have been described in more detail 

by Ziegler and others (1999) and Schmidt and others (2007). 

The Halstead diversion well site (fig. 6B) includes a pumping 

deep well immediately adjacent to the Little Arkansas River to 

induce streamflow into the aquifer for artificial recharge, three 

shallow monitoring wells within 500 ft of the Little Arkansas 

River, two shallow monitoring wells more than 500 ft from 

the Little Arkansas River, and a deep monitoring well near the 

diversion well (table A-1). The Halstead recharge site includes 

the water diverted at the Halstead diversion site that then 

was piped to the Halstead recharge control building where it 

was sampled before being recharged into the aquifer and two 

shallow and two deep (table A-1) monitoring wells near the 

recharge basins, trench, and injection well. The Sedgwick 

recharge site includes the water diverted for recharge from 

the Little Arkansas River near Sedgwick that then was treated 

and piped to a settling basin at the recharge site before being 

sampled and recharged into the aquifer, two shallow, and two 

deep (table A-1) monitoring wells near the recharge basins. 

Ziegler and others (1999) also described the background 

wells, which include 13 shallow monitoring wells along the 

Little Arkansas River (table A-1). The aquifer storage and 

recovery (ASR) prototype sites include 12 deep monitoring 

wells (table A-1) installed by the city of Wichita in 2002 and 

2004 near potential locations for large-scale withdrawal and 

artificial recharge. In addition, 38 index monitoring well (IW) 

sites were established by the city of Wichita throughout the 

study area in 2001; each index site included a shallow and a 

deep monitoring well for a total of 76 monitoring wells (table 

A-1). Additionally, locations of the large-scale recharge facilities (Phase I recharge wells RRW-1 through 4 and Phase I 

recharge basins RB-1 and 2) are shown for future reference in 

figures 6A and 6B. These sites were constructed in 2006 after 

the sampling period described in this report.

Water-Sample Collection

Discrete (one time) and continuous real-time water-quality data are used in this report to describe water quality in the 

Little Arkansas River and the groundwater. Discrete waterquality samples were collected from two surface-water monitoring sites on the Little Arkansas River (sites 07143672 and 

07144100; fig. 1), from demonstration diversion and recharge 

sites, and from index and other wells. Continuous real-time 

water-quality data also were collected at the two surface-water 

monitoring sites.

Discrete Surface and Groundwater-Quality 

Samples

Discrete surface- and groundwater-quality samples were 

collected from 1995 through 2005 throughout the study area. 

Surface-water samples were collected using depth- and widthintegrating techniques (Wilde and Radtke, 1998). Groundwater samples were collected with a noncontaminating submersible pump using methods described in Wood (1976), Koterba 

and others (1995), and Puls and Barcelona (1996). To obtain 

representative samples, at least three to five well volumes were 

purged prior to sample collection. Specific conductance, pH, 

water temperature, dissolved oxygen, ORP, and turbidity were 

measured at 5-minute intervals. Water samples were collected 

after these constituents were stable (within 10 percent for three 

consecutive readings) and turbidity was less than 10 nephelometric turbidity units (NTUs). 

Sampling frequency varied depending on the type of site. 

Samples were collected at least six times per year over a range 

of hydrologic conditions from two surface-water monitoring 

sites on the Little Arkansas River from 1995 through 2005. 

During the recharge demonstration project (1995–2002), 

water-quality samples were collected at least quarterly from 

all monitoring wells at the Halstead and Sedgwick recharge 

sites and from selected monitoring wells at the Halstead diversion site. Water from the diversion well was sampled at least 

monthly while the well was in operation. The treated stream 

water at the Sedgwick recharge site also was sampled at least 

monthly during active artificial recharge activities. Sampling 

frequency from 1995 through 1998 for background wells 

was described in Ziegler and Combs (1997) and Ziegler and 

others (1999). Those background wells that were sampled 

after 1998 were sampled at least annually. Water samples 

from index wells were collected at least six times from 2001 

through 2005. On the basis of analytical results and generally 
Methods 13

small variability in concentrations, sampling frequency for 

the index wells was decreased to annual samples in 2004. The 

ASR prototype wells were sampled at least five times during 2002 through 2005. In previous studies, water samples 

were collected from background wells near the Halstead and 

Sedgwick recharge sites prior to artificial recharge (Ziegler 

and others, 1999, 2001). Analyses of these samples were used 

for determining any effects on water quality in the Equus Beds 

aquifer during the demonstration phase of the recharge project 

(reported herein).

Water samples collected for the recharge project at 

designated data-collection sites during 1995 through 2005 

were analyzed for the constituents listed in table A-2 (in 

the Appendix at the back of this report). All samples were 

analyzed for “key” selected physical properties, major ions, 

nutrients, dissolved trace elements, organic compounds, and 

bacterial and viral indicators (table A-2). Dissolved concentrations of trace elements were defined operationally by filtering 

the water samples through a 0.45-μm pore-size filter. Selected 

samples were analyzed for additional constituents (also listed 

in table A-2), including inorganic compounds, radionuclides, 

organic compounds, and bacterial and viral indicators. The 

radionuclides and additional organic compounds included 

pesticides and their metabolites, volatile organic compounds 

(VOCs), acid and base/neutral compounds, and pharmaceutical and personal care compounds (shown in table A-2, but 

not discussed in this report). Those constituents that were not 

detected in any of the analyses performed for this study are 

noted in table A-2. Summaries of water-quality data collected 

from 1995 through 2005 as part of the Equus Beds Groundwater Recharge Project and constituents that had at least one 

detection in water samples from at least one site sampled for 

this study are presented in the Appendix (at the back of this 

report) in table A-3 (physical properties, dissolved solids, and 

sediment), table A-4 (major ions and nutrients), table A-5 (dissolved trace elements), table A-6 (organic compounds), table 

A-7 (triazine herbicides and bacterial and viral indicators), and 

table A-8 (radionuclide constituents).

Methods used to analyze water samples for physical 

properties and to determine concentrations of dissolved solids, 

major ions, nutrients, dissolved trace elements, radionuclides, 

organic compounds, and coliform bacteria in water samples 

were described by Ziegler and Combs (1997). Arsenic speciation data also were collected and analyzed using methods 

described in Garbarino and others (2002). Additional fecal 

and viral indicator bacteria analyses were done using methods 

described by Bisson and Cabelli (1979, 1980), Britton and 

Greeson (1987), Armon and Payment (1988), Payment and 

Franco (1993), and United States Environmental Protection 

Agency (1996, 2000, 2001a, 2006b-e). Samples were analyzed 

by the city of Wichita laboratory (Wichita, Kansas), the USGS 

National Water Quality Laboratory (Denver, Colorado), and 

the USGS Organic Geochemistry Research Laboratory (Lawrence, Kansas). Further information regarding data-collection 

methods, preservation, sample holding times, analytical methods, and reporting levels can be found in Ziegler and Combs 

(1997). 

In addition to the summary data presented in this report, 

individual sample analyses are available on the World Wide 

Web at http://waterdata.usgs.gov/ks/nwis/qw. Statistical 

summaries of these water-quality data are available at http://

ks.water.usgs.gov/Kansas/studies/equus/ (accessed December 

2006). Average and median concentrations of water-quality 

constituents from discrete samples presented in this report 

were calculated using the summary statistics program that is 

part of the USGS National Water Information System (NWIS). 

The program uses statistical methods described in Helsel 

(2005). This program did not compute an average or median 

concentration for a data set (a site or group of sites) if there 

were five or fewer observations (samples analyzed for a particular constituent). A median concentration was determined for 

the data set if six or more observations were available, even if 

some of the observations were censored. Censored observations were those concentrations reported in samples in which 

a constituent is absent or is present at concentrations less than 

the reporting level of the analysis method. If a constituent was 

present at or above the reporting level of the analysis method, 

it was referred to as uncensored. Censored and uncensored 

observations commonly were referred to as nondetections and 

detections. A data set must contain at least six detections for 

its average to be computed by the NWIS program; if there 

were fewer than six detections, the average was not computed. 

If the number of observations in a data set included at least six 

detections but more than 5 percent of the observations were 

nondetections, then the program estimated the average using 

a log-probability regression procedure (Helsel, 2005). Where 

the program did not compute an average for a groundwater 

site for a constituent mapped in this report, one was calculated 

or assigned. If there was only one observation or measurement 

for the particular constituent at a site, then the value of that 

observation was used. If there was more than one observation 

for a constituent at a site, a value of one-half the reporting 

level was assigned to those observations that were less than 

the reporting level. The average then was calculated as the 

sum of all the observations divided by the number of observations. Where the resulting average was less than the reporting 

level for the constituent, it was assigned a concentration indicating that the average was less than the reporting level. 

Continuous Surface-Water-Quality Monitoring

Beginning in 1998, the streamflow-gaging stations on the 

Little Arkansas River at Highway 50 near Halstead and near 

Sedgwick were each equipped with a multisensor monitor to 

continuously measure specific conductance, pH, water temperature, dissolved oxygen, and turbidity in the stream. The 

sensors were calibrated and maintained according to methods 

presented in Wilde and Radke (1998) and Wagner and others 

(2000). Measurements from continuous monitoring sensors 

were checked against a calibrated field meter during site visits. 
14 Water Quality in the Equus Beds Aquifer and the Little Arkansas River, South-Central Kansas 

Continuous monitoring sensors were cleaned of any mud or 

debris, checked against known standards, and calibrated as 

needed. Continuous monitoring sensors collected data every 

15 to 60 minutes daily. The data then were transmitted by 

satellite from a data-collection platform (DCP) to the USGS 

computer in Lawrence, Kansas. Data are available on the 

World Wide Web at http://nrtwq.usgs.gov/ks.

Quality Assurance and Quality Control

Replicate, blank, and standard reference samples were 

collected as a part of quality assurance/quality control (QA/

QC) measures. More than 200 quality-control samples were 

collected from 1995 through 2004; most of these were replicate and blank samples (data available on request from the 

U.S. Geological Survey, Lawrence, Kansas). 

Replicate samples were collected to identify the variability in the sampling and analysis methods (Wilde and Radke, 

1998). A replicate sample is a set of two (or more) samples 

from the same location that are collected close in time so that 

they are thought to be representative of the ambient water 

composition at one collection time (Wilde and Radke, 1998). 

Replicate samples were compared with their respective original sample, and the percentage differences were calculated as 

the difference between the replicate and original sample concentrations divided by the average of the two values multiplied 

by 100. The generally good agreement (less than 10-percent 

difference) of original and replicate results for constituent 

concentration substantially larger than the reporting level 

indicated that sampling and analysis methods were consistent 

and did not introduce large or biased variability into the data 

set (fig. A-1 in the Appendix at the back of this report). 

Blank samples composed of deionized water were 

prepared for QA/QC from 1995 through 2004. Blank samples 

were analyzed to check for contamination through all of the 

sampling, processing, and analytical procedures. Dissolved 

solids and sodium were detected in about 7 and 11 percent of 

the blank samples at concentrations more than 1.0 and 0.03 

mg/L [figs. A-2 (1995–2004) and A-3 (1999–2004) in the 

Appendix, at the back of this report]. The detections of sodium 

were near reporting levels and were likely caused by impurities in the acid used to the preserve the samples. Fluoride was 

detected in about 8 percent (1995–2004) of blank samples and 

recently is more prevalent (15 percent, 1999–2004, fig. A-3) 

at concentrations that ranged from less than 0.02 to 0.1 mg/L. 

Fluoride detected in environmental samples ranged from less 

than 0.02 to 0.82 mg/L; therefore, fluoride concentrations in 

environmental samples could be affected by sampling and 

analytical errors in about 10 percent of the samples. 

Standard reference samples were analyzed by the Wichita 

Municipal Water and Wastewater Laboratory at least annually and submitted to the USGS Branch of Quality Systems 

for sample analysis and evaluation of laboratory performance. 

Evaluations of the Wichita laboratory indicated consistently 

good to excellent ratings (within 2 to 5 percent) in major ion 

and trace-element analysis. However, nutrient analysis was 

rated marginal for total nitrogen and phosphorus but was 

within 20 percent of the most probable value during the Equus

Beds artificial recharge project. Results are available on the 

World Wide Web at http://bqs.usgs.gov/srs/.

Regression Analysis 

Data for selected water-quality constituents were analyzed further using linear regression statistical analysis methods. Statistical methods presented in Helsel and Hirsch (1992, 

2002) were used by Christensen and others (2000, 2003) to 

develop regression models between water-quality constituent 

concentrations in water samples in surface water and physical 

properties such as specific conductance, pH, water temperature, and turbidity. These models are used to provide real-time 

computations of concentrations and loads for selected major 

ions, nutrients, arsenic, atrazine, and fecal indicator bacteria in 

the Little Arkansas River. These computed concentrations are 

available on the World Wide Web at http://nrtwq.usgs.gov/ks/.

Data also were analyzed using ordinary least-square 

regression (Helsel and Hirsch, 2002) to develop models for 

estimating concentrations of water-quality constituents in 

groundwater. These models help explain the current distribution of these constituents in the study area and also provided the ability to compute concentrations of constituents 

in groundwater for future use or in parts of the Equus Beds 

aquifer without complete chemical analyses using easily measured onsite sensors. For each index well, individual sample 

concentrations of selected constituents were plotted against 

sampled onsite water-quality constituents measured during 

sampling, such as specific conductance, dissolved oxygen, and 

ORP. Graphs were examined visually to detect any relations 

between response and explanatory variables. Three relatively 

strong relations (coefficient of determination, R2

, between 

0.5 and 1.0) for groundwater were developed through statistical regression—(1) specific conductance and sulfate concentration, (2) specific conductance and chloride concentration, 

and (3) ORP and arsenic concentration.

Effective Porosity

Effective porosity is a measure of the interconnected 

pore volume within a rock layer that contributes to fluid 

flow (Lohman, 1972) and is expressed as a percentage of 

the total volume. Effective porosity for the entire thickness 

of the aquifer was computed for this study from the examination of water-well drillers’ logs (Water Well Completion 

Forms WWC5) for the 38 deep index wells (data on file 

with the Kansas Geological Survey, Lawrence, Kansas) and 

from tables of location, total thickness, and sand thickness 

of 78 soil borings made in the study area (Robert Jacques, 

Burns and McDonnell Engineering Consultants, Kansas City, 

Missouri, written commun., November 22, 2004). Only the 

sand and gravel layers at each site were considered to have 
Water Quality in the Equus Beds Aquifer and Little Arkansas River, 1995–2005 15

useful porosity because clay and silt layers were considered 

to be much more restrictive to groundwater flow. An effective 

porosity of 25 percent was estimated by Burns and McDonnell Engineering Consultants for the city of Wichita for the 

sand and gravel layers. This value was within the range of 

average effective porosity values reported for sand and gravel 

by McWhorter and Sunada (1977). Effective porosity for the 

aquifer was estimated as the thickness of sand and gravel 

encountered at each well or soil boring divided by the total 

thickness of unconsolidated deposits penetrated at each site 

multiplied by the estimated effective porosity for sand and 

gravel of 25 percent. 

Area Calculations

The percentage of the study area considered to have a 

constituent concentration exceeding a particular concentration was computed on the basis of manually drawn contours 

of equal concentration. These contours were based on average 

values of constituent concentrations in water samples from 

wells in and near the study area. The area within each contour 

of equal concentration was calculated using a geographic 

information system (GIS). The percentage of area was determined by dividing the sum of the areas with concentrations 

more than the chosen concentration in the study area by the 

total study area and multiplying the result by 100.

Water Quality of the Equus Beds 

Aquifer and Little Arkansas River, 

1995–2005

The chemical composition of natural water is determined 

primarily by the lithology in which the water resides or passes 

through (Hem, 1992). Other factors affecting water quality 

include precipitation, mixing with water from other sources, 

geochemical and biochemical processes, and human activities that contribute additional constituents or produce chemical reactions such as ion exchange or oxidation-reduction 

processes. 

The Equus Beds aquifer consists of alluvial deposits as 

much as 250 ft thick that lie on top of the shale in the Wellington Formation, which occurs throughout most of the study 

area. Dissolution of the underlying Hutchinson Salt Member 

of the Wellington Formation and the subsequent collapse of 

overlying rock created a depression in much of the study area 

and allowed the accumulation of materials that make up the 

Equus Beds aquifer. These materials consist of sand and gravel 

interbedded with clay and silt. A trough or bedrock low filled 

with unconsolidated deposits about 200 ft thick in the center 

of the study area (commonly referred to as the McPherson 

channel) (figs. 3, 5, 7, and 8) represents the deepest part of the 

aquifer and is a primary flow path for water within the Equus

Beds aquifer. Flow of groundwater in the study area generally 

is from west to east or northeast and becomes more southerly 

near and to the east of the bedrock low (fig. 5) because of the 

effects of city pumpage and discharge to the Little Arkansas 

River (Aucott and others, 1998). Generally, water altitudes in 

the shallow index wells are higher than those in deep index 

wells indicating there is a downward gradient throughout the 

aquifer (Data on file with the U.S. Geological Survey, Lawrence, Kansas). 

Water-quality changes may be more rapid in areas with 

larger effective porosity. Estimated effective porosity of the 

entire thickness of the Equus Beds aquifer in the study area is 

illustrated in figure 8. Areas with the largest estimated effective porosity, more than 15 percent, are along the western part 

of the study area, along the Arkansas and Little Arkansas Rivers, and in an area stretching from Halstead to the deepest part 

of the bedrock low. The presence of clay layers and the depth 

below land surface also affect effective porosity and, in turn, 

water chemistry in the aquifer.

Of all the constituents analyzed, only those that frequently exceeded USEPA Federal drinking-water-quality criteria, those that are of potential concern for artificial recharge 

operations, and those that may change as a result of artificial 

recharge are discussed in this report. These constituents 

include dissolved ions (sulfate and chloride), nutrients, trace 

elements (arsenic, iron, and manganese), triazine herbicides 

(atrazine), and alachlor, and bacterial (fecal coliform, Escherichia coli, and total coliform) and viral (Clostridium perfringens and E. coli coliphage) indicators. Summaries of these 

constituents are presented in table 1 for the two surface-water 

monitoring sites on the Little Arkansas River and in table 2 for 

background wells, ARS prototype wells, and shallow and deep 

index wells. Detailed summaries of all water-quality monitoring results are presented in Appendix tables A-3 through A-8. 

Water-quality constituents that were monitored included physical properties, major ions, nutrients, trace elements, radionuclides, organic compounds, fecal bacterial and viral indicators, 

and suspended sediment.

Physical Properties

Physical properties were measured onsite during sample 

collection and include streamflow discharge, groundwater 

level, specific conductance, pH, water temperature, turbidity, 

dissolved oxygen, and ORP. Specific conductance and ORP 

are examined in detail in this report because of their relation to 

many of the potential water-quality constituents of concern for 

artificial recharge.

Specific Conductance

Specific conductance measures the ability of water to 

conduct an electrical current and is an indirect measurement of the presence of inorganic dissolved solids in water 

(Hem, 1992). Previous studies have successfully used specific conductance to compute concentrations of water-quality 
16 Water Quality in the Equus Beds Aquifer and the Little Arkansas River, South-Central Kansas 

Newton

Maize

Colwich

Burrton

0 1 2 3 4 5 MILES

0 1 2 3 4 5 KILOMETERS

Base from U.S. Geological Survey digital data, 1:100,000, 1983

Universal Transverse Mercator projection,

Zone 14

Horizontal coordinate information is referenced to the North American

 Datum of 1983 (NAD 83)

97°40'

38°

38°50’

38°05’

55’

35' 30' 97°25'

West Em

ma Creek

Middle Emma Creek

East Emma Creek

Em

ma Creek

Sand Creek

Jester Creek

Little Arkansas River

ARKANSAS

RIVER

Kisiwa Creek

Big Slough

R. 3 W. R. 2 W. R. 1 W.

T.

26

S.

T.

25

S.

T.

24

S.

T.

23

S.

T.

22

S.

R. 4 W.

Study area

Bedrock contour—Shows altitude of bedrock surface.

 Interval 100 feet. Datum is National Geodetic

 Vertical Datum of 1929

Intermediate bedrock contour—Altitude of bedrock

 surface. Interval 20 feet. Datum is National Geodetic

 Vertical Datum of 1929

Bedrock depression contour

Approximate location of bedrock low (McPherson channel)

EXPLANATION

RENO COUNTY SEDGWICK COUNTY

HARVEY COUNTY

1,300

1,280

1,2601,240

1,220

1,320

1,340

1,360

1,300

1,280

1,260

1,240

1,220

Black

Kettle Creek

1,200

1,200

1,200

1,180

1,160

1,140

1,200

1,220

1,220

1,220

1,240

1,240

1,260

1,260

1,280

1,280

1,240

1,260

1,280

1,1801,160 1,140

1,160

1,180

1,200

1,220

1,240

1,260

1,280

1,280

1,200

1,220

1,300

1,320

1,340

Halstead

1,280

1,260

1,240

1,300

1,300

1,320

1,340 1,200

1,160

1,180

1,140

1,500

Andale

Mount Hope

1,400

1,420

1,440

1,460

1,480

1,380 1,360

1,340

1,320

1,300

1,300

1,320

1,300

1,280

1,260

1,240

1,220

1,320

1,340

1,360

1,380

1,400

Valley

Center

Bentley

Sedgwick

Wichita

Little Arkansas River

1,400

1,420

1,220

1,240

1,200 1,240

1,240

1,300

1,120

1,140

1,220

1,180

1,320

1,340

1,360

1,240

1,220

1,240

1,260

1,140

1,140

1,140

1,140

1,140

1,140

1,240

1,220

1,120

Cowskin Creek

Boundary of study area

Boundary of study area

Bedrock data point from:

Myers and others, 1996

Burns and McDonnell, 2004

U.S. Geological Survey, data on file, 1988

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

 real-time water-quality monitoring site

Figure 7. Altitude of bedrock surface below Equus Beds aquifer and approximate location of bedrock low in study area. Bedrock 

contours are modified from Myers and others, 1996. Point data are from Myers and others, 1996; Robert Jacques, Burns and McDonnell, 

written commun., 2004; and data on file with U.S. Geological Survey, Lawrence, Kansas.
Water Quality in the Equus Beds Aquifer and Little Arkansas River, 1995–2005 17

Wichita

Newton

Maize

Sedgwick

Colwich

Mount Hope

Andale

Hesston

0 1 2 3 4 5 MILES

0 1 2 3 4 5 KILOMETERS

9

9

3

9

3

17

18

15

18

15

15

18

14

13

16 11 14 18

12

15 13

16

10

11

13 14

15

17

14

14

11 17

12 14

15

16

14

10

11

10

14

12 13

12 12 14

15

11

15

12

17

Bentley

IW-38C15 IW-37C

23 IW-36C

19 IW-35C14

IW-34C20

IW-33C20 IW-32C

20

IW-31C11 IW-30C15

IW-29C

10

IW-26C

11 IW-25C

19 IW-24C

18

IW-23C10 IW-22C17 IW-21C

12

IW-27C

20

IW-19C13

IW-18C

16

IW-16C

19

IW-17C

9 IW-15C

13

IW-14C14

IW-10C

15 IW-09C

19

IW-08C

16

IW-13C

16

IW-07C

11

IW-06C

14 IW-05C

18

IW-03C19

IW-02C7

IW-01C

8

IW-11C17

IW-12C14

IW-04C15

IW-28C

18

IW-20C18

Base from U.S. Geological Survey digital data, 1:100,000, 1983

Universal Transverse Mercator projection,

Zone 14

Horizontal coordinate information is referenced to the North American

 Datum of 1983 (NAD 83)

97°40'

38°

38°50’

38°05’

55’

35' 30' 97°25'

Little Arkansas River

West Em

ma Creek

Middle Emma Creek

East Emma Creek

Em

ma Creek

Sand Creek

Jester Creek

Valley

Center

Little Arkansas River

Kisiwa Creek

Big Slough

Cowskin Creek

R. 3 W. R. 2 W. R. 1 W.

T.

26

S.

T.

25

S.

T.

24

S.

T.

23

S.

T.

22

S.

R. 4 W.

RENO COUNTY SEDGWICK COUNTY

HARVEY COUNTY

Bentley

Black

Kettle Creek

Halstead

07144100

07143672

ARKANSAS RIVER

Burrton

Boundary of study area

Boundary of study area

16

EXPLANATION

Estimated effective porosity, in percent

 Less than 5

 5 to less than 10

 10 to less than 15 Index well and site identifier—Lower number

 is estimated effective porosity, in percent

 Soil boring site—Number is estimated effective

 porosity, in percent

IW-15C13

07144100

15 to less than 20

Equal to or greater

 than 20 

Approximate location of bedrock low

 (McPherson channel)

Data-collection sites

U.S. Geological Survey streamflow-gaging

 station, continuous real-time water-quality

 monitoring site, and site identifier

Figure 8. Estimated effective porosity in study area. Soil boring data are from Robert Jacques, Burns and McDonnell, 

written commun., November 11, 2004; index well data are on file with U.S. Geological Survey, Lawrence, Kansas.
18 Water Quality in the Equus Beds Aquifer and the Little Arkansas River, South-Central Kansas Table 1. Summary of selected water-quality data from surface-water samples collected from February 1995 through December 2005 as a part of the Equus Beds Groundwater Recharge Project, south-central Kansas. [mg/L, milligrams per liter; DWA, Drinking Water Advisory; SDWR, Secondary Drinking-Water Regulation; MCL, Maximum Contaminant Level; <, less than; μg/L, micrograms per liter; cols/100 mL, colonies per 100 milliliters; MCLG, Maximum Contaminant Level Goal] Water-quality constituent Water-quality criteria Number of samples Minimum Maximum Average Median Detected in percentage of samples Percentage of samples exceeding criteria Percentage of replicate samples exceeding criteria Surface-water monitoring sites Sites: Little Arkansas River at Highway 50 near Halstead (07143672) and Little Arkansas River at Sedgwick (07144100), Kansas Sodium, dissolved (mg/L) 20 mg/L (DWA)1 347 1.5 498 70.0 59 100 77.5 72.3 Sulfate, dissolved (mg/L) 250 mg/L (SDWR)1 347 5 312 39.6 40 97.7 .288 0 Chloride, dissolved (mg/L) 250 mg/L (SDWR)1 352 5 932 125 91 99.1 14.5 6.52 Nitrite plus nitrate as nitro- gen, dissolved (mg/L) 10 mg/L (MCL)1 306 <.02 9.4 2.94 .85 89.9 0 0 Arsenic, dissolved (μg/L) 10 μg/L (MCL)1 166 1 14.1 5.00 5 98.8 8.43 11.1 Iron, dissolved (μg/L) 300 μg/L (SDWR)1 347 <5.00 860 233.1 10 65.7 1.73 2.13 Manganese, dissolved (μg/L) 50 μg/L (SDWR)1 346 <1 1,140 2147 60 80.1 48.0 53.2 Total coliform bacteria (cols/100 mL) 0 cols/100 mL (MCLG)1 297 <1 9,000,000 246,200 1,700 92.9 92.9 86 Fecal coliform bacteria3(cols/100 mL) 200 cols/100 mL (Guideline)4 345 <1 4,000,000 25,500 860 98.3 76.2 78.4 2,000 cols/100 mL (Guideline)4 113 4 20,000 1,270 170 96.5 15.9 5.9 Escherichia coli (cols/100 mL) 262 cols/100 mL (Guideline)6 56 32 41,000 2,470 215 100 48.2 0 2,358 cols/100 mL (Guideline)6 10 21 2,200 609 345 100 0 0 Atrazine herbicide 3 μg/L as an annual average1 (MCL) 495 .030 48 5.81 3.45 97.8 54.1 45.0 Triazine herbicide screen, dissolved (μg/L as atrazine) 3 μg/L as an annual average1 (MCL) 3,165 .1 50 3.71 2 96.2 30.7 36.3 Alachlor (μg/L) 2 μg/L (MCL)1 490 <.002 28 2.544 .13 70.2 4.90 2.56

1 U.S. Environmental Protection Agency (2006a).2 Value is estimated by using a log-probability regression to predict the values of data below the detection level.3 For fecal coliform bacteria, the primary contact recreation surface-water criterion of 200 colonies per 100 milliliters was used from April 1 to October 31 (when most water-contact recreation occurs); 

from November 1 to March 31, the criterion of 2,358 colonies per 100 milliliters was used.

4 Recreational-use guideline (Kansas Department of Health and Environment, 2001).5 For Escherichia coli, the primary contact recreation surface-water quality criterion of 262 colonies per 100 milliliters was used from April 1 to October 31 for Class B (public access) stream segments; 

from November 1 to March 31, the criterion of 2,358 colonies per 100 milliliters was used.

6 Recreational-use guideline (Kansas Department of Health and Environment, 2004).
Water Quality in the Equus Beds Aquifer and Little Arkansas River, 1995–2005 19

Table 2. Summary of selected water-quality data from groundwater samples collected from February 1995 through December 2005 as a part of the Equus Beds Groundwater 

Recharge Project, south-central Kansas.

[mg/L, milligrams per liter; DWA, Drinking Water Advisory; SDWR, Secondary Drinking-Water Regulation; <, less than; MCL, Maximum Contaminant Level; μg/L, micrograms per liter; cols/100 mL, colonies per 100 milliliters; MCLG, Maximum Contaminant Level Goal; --, not determined]

Water-quality constituent Water-quality criteria

Number 

of

samples 

Minimum Maximum Average Median

Detected in 

percentage 

of samples

Percentage 

of samples 

exceeding

criteria

Percentage of replicate 

samples

exceeding 

criteria

Percentage 

of wells

with average

exceeding 

criteria

Background wells

Wells: TH-02-95, TH-06-95, TH-10-95, TH-12-95, Sedgwick well, EB-142-A3, city well-Sedgwick, 

Alta Mills well, TH-08-A1, TH-08-A2, TH-08-A3, TH-08-A4, TH-08-A5 

Sodium, dissolved (mg/L) 20 mg/L (DWA)1 205 17.8 90.7 43.2 43.6 100 95.1 94.1 100

Sulfate, dissolved (mg/L) 250 mg/L (SDWR)1 205 5 186 57.3 55 98 0 0 0Chloride, dissolved (mg/L) 250 mg/L (SDWR)1 205 <5.00 65 2 20.6 21 90.7 0 0 0

Nitrite plus nitrate as nitrogen, 

dissolved (mg/L)

10 mg/L (MCL)1 205 <.010 11.7 2.837 <.020 31.2 2.44 5.88 0

Arsenic, dissolved (μg/L) 10 μg/L (MCL)1 155 <1.00 15.4 2 6.19 6.6 84.5 21.3 14.3 23.1Iron, dissolved (μg/L) 300 μg/L (SDWR)1 205 <5.00 1,850 2 607 620 82.4 73.7 76.5 69.2Manganese, dissolved (μg/L) 50 μg/L (SDWR)1 205 0 4,320 322 250 99.5 88.8 88.2 92.3

Total coliform bacteria 

(cols/100 mL)

0 cols/100 mL 

(MCLG)1

204 <1.00 636 2 9.60 <1.00 28.9 28.9 47.1 --

Fecal coliform bacteria3

(cols/100 mL)

200 cols/100 mL 

(Guideline)4

152 <1.00 6 <1.00 <1.00 3.29 0 0 0

2,000 cols/100 mL 

(Guideline)4

52 <1.00 <4.00 <1.00 <1.00 0 0 0 0

Atrazine herbicide 3 μg/L as an annual 

average1 (MCL)

82 <.001 1.6 2.056 <.050 39.0 0 0 0

Triazine herbicide screen, 

dissolved (μg/L as atrazine)

3 μg/L as an annual 

average1 (MCL)

214 <.010 2 2.069 <.100 17.3 0 0 0

Alachlor (μg/L) 2 μg/L (MCL)1 81 <.002 .017 <.009 <.004 1.23 0 0 0
20 Water Quality in the Equus Beds Aquifer and the Little Arkansas River, South-Central Kansas Table 2. Summary of selected water-quality data from groundwater samples collected from February 1995 through December 2005 as a part of the Equus Beds Groundwater Recharge Project, south-central Kansas.—Continued [mg/L, milligrams per liter; DWA, Drinking Water Advisory; SDWR, Secondary Drinking-Water Regulation; <, less than; MCL, Maximum Contaminant Level; μg/L, micrograms per liter; cols/100 mL, colonies per 100 milliliters; MCLG, Maximum Contaminant Level Goal; --, not determined] Water-quality constituent Water-quality criteria Number of samples Minimum Maximum Average Median Detected in percentage of samples Percentage of samples exceeding criteria Percentage of replicate samples exceeding criteria Percentage of wells with average exceeding criteria Aquifer storage and recovery prototype wells Wells: DW-TW-01 through DW-TW-09, RRW-01, RRW-02, RRW-03 Sodium, dissolved (mg/L) 20 mg/L (DWA)1 76 14.9 44.4 30.5 30.9 100 90.8 100 91.7 Sulfate, dissolved (mg/L) 250 mg/L (SDWR)1 76 7.1 135 17.3 15.1 100 0 0 0 Chloride, dissolved (mg/L) 250 mg/L (SDWR)1 76 <5.00 57 28.90 6 93.4 0 0 0 Nitrite plus nitrate as nitrogen, dissolved (mg/L) 10 mg/L (MCL)1 76 <.020 1.07 2.054 <.020 43.4 0 0 0 Arsenic, dissolved (μg/L) 10 μg/L (MCL)1 76 1 21.4 7.46 7.05 98.7 27.6 20 25 Iron, dissolved (μg/L) 300 μg/L (SDWR)1 76 <5.00 470 227.7 <5.00 36.8 1.32 0 0 Manganese, dissolved (μg/L) 50 μg/L (SDWR)1 76 40 330 198 190 100 97.4 0 100 Total coliform bacteria (cols/100 mL) 0 cols/100 mL (MCLG)1 76 <1.00 224 28.33 <1.00 23.7 23.7 0 -- Fecal coliform bacteria3 (cols/100 mL) 200 cols/100 mL (Guideline)4 34 <1.00 <1.00 <1.00 <1.00 0 0 0 0 2,000 cols/100 mL (Guideline)4 42 <1.00 1 <1.00 <1.00 2.38 0 0 0 Atrazine herbicide 3 μg/L as an annual 

average1 (MCL)

53 <.007 <.050 <.030 <.007 0 0 0 0

Triazine herbicide screen, 

dissolved (μg/L as atrazine)

3 μg/L as an annual 

average1 (MCL)

76 <.100 .8 2.026 <.100 7.89 0 0 0

Alachlor (μg/L) 2 μg/L (MCL)1 43 <.004 <.050 <.050 <.005 0 0 0 0
Water Quality in the Equus Beds Aquifer and Little Arkansas River, 1995–2005 21

Table 2. Summary of selected water-quality data from groundwater samples collected from February 1995 through December 2005 as a part of the Equus Beds Groundwater 

Recharge Project, south-central Kansas.—Continued

[mg/L, milligrams per liter; DWA, Drinking Water Advisory; SDWR, Secondary Drinking-Water Regulation; <, less than; MCL, Maximum Contaminant Level; μg/L, micrograms per liter; cols/100 mL, colonies per 100 milliliters; MCLG, Maximum Contaminant Level Goal; --, not determined]

Water-quality constituent Water-quality criteria

Number 

of

samples 

Minimum Maximum Average Median

Detected in 

percentage 

of samples

Percentage 

of samples 

exceeding

criteria

Percentage of replicate 

samples

exceeding 

criteria

Percentage

 of wells

with average 

exceeding 

criteria

Areal assessment index wells (shallow monitoring wells)

Wells: IW-01A through IW-38A 

Sodium, dissolved (mg/L) 20 mg/L (DWA)1 284 12.5 330 87.6 64.7 100 95.1 91.7 94.7

Sulfate, dissolved (mg/L) 250 mg/L (SDWR)1 284 5 760 155 115 98.9 19.4 16.7 18.4

Chloride, dissolved (mg/L) 250 mg/L (SDWR)1 284 5 773 79.1 40.5 99.3 7.04 16.7 5.26

Nitrite plus nitrate as nitrogen, 

dissolved (mg/L)

10 mg/L (MCL)1 284 <.020 23.8 23.61 .19 70.4 15.1 31 13.2

Arsenic, dissolved (μg/L) 10 μg/L (MCL)1 281 <1.00 55 2

4 <1.00 47.7 10.7 12 10.5

Iron, dissolved (μg/L) 300 ug/L (SDWR)1 284 <5.00 40,700 22,440 78 60.6 37.3 33.3 39.5

Manganese, dissolved (μg/L) 50 μg/L (SDWR)1 284 <1.00 1,490 2282 110 73.9 55.6 54.3 57.9

Total coliform bacteria 

(cols/100 mL)

0 cols/100 mL 

(MCLG)1

271 <1.00 368 28.72 <1.00 32.8 32.8 23.1 --

Fecal coliform bacteria3

(cols/100 mL)

200 cols/100 mL 

(Guideline)4

203 <1.00 120 1.15 <1.00 1.97 0 0 0

2,000 cols/100 mL 

(Guideline)4

82 <1.00 24 <1.00 <1.00 5 0 0 0

Escherichia coli

(cols/100 mL)

262 cols/100 mL 

(Guideline)6

9 <1.00 1 <1.00 <1.00 0 0 0 0

Atrazine herbicide 3 μg/L as an annual 

average (MCL)

105 <.007 1.2 2.048 .005 55.2 0 0 0

Triazine herbicide screen, 

dissolved (μg/L as atrazine)

3 μg/L as an annual 

averagea (MCL)

272 <.100 2 2.057 <.100 14 0 0 0

Alachlor (μg/L) 2 μg/L (MCL)1 99 <.004 .013 <.020 <.005 3.03 0 0 0
22 Water Quality in the Equus Beds Aquifer and the Little Arkansas River, South-Central Kansas Table 2. Summary of selected water-quality data from groundwater samples collected from February 1995 through December 2005 as a part of the Equus Beds Groundwater Recharge Project, south-central Kansas.—Continued [mg/L, milligrams per liter; DWA, Drinking Water Advisory; SDWR, Secondary Drinking-Water Regulation; <, less than; MCL, Maximum Contaminant Level; μg/L, micrograms per liter; cols/100 mL, colonies per 100 milliliters; MCLG, Maximum Contaminant Level Goal; --, not determined] Water-quality constituent Water-quality criteria Number of samples Minimum Maximum Average Median Detected in percentage of samples Percentage of samples exceeding criteria Percentage of replicate samples exceeding criteria Percentage of wells with average exceeding criteria Areal assessment index wells (deep monitoring wells) Wells: IW-01C through IW-38C Sodium, dissolved (mg/L) 20 mg/L (DWA)1 288 17.4 409 97.3 91.8 100 95.5 95.2 94.7 Sulfate, dissolved (mg/L) 250 mg/L (SDWR)1 288 5 890 111 70 99.3 13.9 14.3 13.2 Chloride, dissolved (mg/L) 250 mg/L (SDWR)1 287 5 1460 125 70 97.6 8.36 28.6 5.26 Nitrite plus nitrate as nitrogen, dissolved (mg/L) 10 mg/L (MCL)1 288 <.020 9.61 2.419 .01 50.3 0 0 0 Arsenic, dissolved (μg/L) 10 μg/L (MCL)1 286 <1.00 23.9 2 7.43 5.9 83.2 34.3 27.3 34.2 Iron, dissolved (μg/L) 300 μg/L (SDWR)1 288 <5.00 15,800 2 1,470 120 70.5 43.4 52.4 44.7 Manganese, dissolved (μg/L) 50 μg/L (SDWR)1 288 0 1,450 441 310 99.3 92 76.2 94.7 Total coliform bacteria (cols/100 mL) 0 cols/100 mL (MCLG)1 273 <1.00 84 2 1.77 <1.00 18.3 18.3 0 -- Fecal coliform bacteria3 (cols/100 mL) 200 cols/100 mL (Guideline)4 204 <1.00 4 <1.00 <1.00 .98 0 0 0 2,000 cols/100 mL (Guideline)4 81 <1.00 21 <1.00 <1.00 2.47 0 0 0 Escherichia coli (cols/100 mL) 262 cols/100 mL (Guideline)6 10 <1.00 1 <1.00 <1.00 10 0 0 0 Atrazine herbicide 3 μg/L as an annual average (MCL)1 51 <.007 .07 2.010 <.050 21.6 0 0 0 Triazine herbicide screen, dissolved (μg/L as atrazine) 3 μg/L as an annual average (MCL)1 272 <.100 .3 <.100 <.100 1.47 0 0 0 Alachlor (μg/L) 2 μg/L (MCL)1 41 <.004 <.050 <.050 <.005 0 0 0 0 1 U.S. Environmental Protection Agency (2006a).

2 Value is estimated by using a log-probability regression to predict the values of data below the detection level.3 For fecal coliform bacteria, the primary contact recreation surface-water criterion of 200 cols/100 mL was used from April 1 to October 31 (when most water-contact recreation occurs); from November 1 

to March 31, the criterion of 2,358 colonies per 100 milliliters was used.

4 Recreational-use guideline (Kansas Department of Health and Environment, 2001).5 For Escherichia coli, the primary contact recreation surface-water quality criterion of 262 colonies per 100 milliliters was used from April 1 to October 31 for Class B (public access) stream segments; 

from November 1 to March 31, the criterion of 2,358 colonies per 100 milliliters was used.

6 Recreational-use guideline (Kansas Department of Health and Environment, 2004).
Water Quality in the Equus Beds Aquifer and Little Arkansas River, 1995–2005 23

constituents, such as sulfate and chloride, in surface water 

(Christensen and others, 2000, 2003). 

Specific conductance at 25 degrees Celsius (°C) was 

measured in water samples collected from surface-water sites 

during 1995 through 2005 ranged from 40 to 3,550 microsiemens per centimeter at 25 o

C (μS/cm), with median values 

of 864 μS/cm in the Little Arkansas River near Halstead and 

657 μS/cm near Sedgwick (table A-3). Specific conductance 

in the treated stream water used for recharge at the Sedgwick 

recharge site ranged from 212 to 1,300 μS/cm, with a median 

value of 570 μS/cm.

Specific conductance measurements by the continuous 

monitoring sensors during 1999 through 2005 at the surfacewater monitoring sites on the Little Arkansas River near 

Halstead and near Sedgwick were within the range of those 

measured in water samples collected at these sites. However, 

the specific conductance median values of 1,020 μS/cm near 

Halstead and 816 μS/cm near Sedgwick from the continuous monitoring data were larger than those from the collected 

samples because of a more complete (hourly measurements) 

data set and a larger part of continuous monitoring measurements were made during lower flow conditions.

Specific conductance measurements of groundwater 

ranged from 108 μS/cm in well IW-01A to 4,520 μS/cm in 

well IW-08C (table A-3). Average values of specific conductance in groundwater are shown in figures 9A for the shallow parts of the aquifer and in figure 9B for the deep parts of 

the aquifer. The area of largest specific conductance in both 

shallow and deep parts of the aquifer was near Burrton and 

is associated with past oil and gas activities (Williams and 

Lohman, 1949; Whittemore, 2007). Large specific conductance values (larger than 1,000 μS/cm) were measured along 

parts of Kisiwa Creek and the Arkansas River in both shallow 

and deep parts of the aquifer. Areas of larger specific conductance generally corresponded to areas of larger effective 

porosity near Burrton and along the Arkansas River. Distribution of specific conductance in the Equus Beds aquifer has 

not changed substantially since 1979 and 1980 when Hathaway and others (1981) reported the largest specific conductance values were near Burrton, south of Kisiwa Creek, and 

along the Arkansas River, and smaller values occurred in the 

northern and eastern parts of the study area of the Equus Beds 

Groundwater Recharge Project. 

Oxidation-Reduction Potential

ORP is measured in millivolts (mV) relative to the 

standard hydrogen electrode and indicates the ability of constituents in water to cause oxidation or reduction reactions. 

ORP was reported only in groundwater samples. The larger 

the ORP, the more oxidizing are the conditions. For example, 

ORP values of more than 250 mV indicated that the dominant 

iron species in groundwater was ferric iron, which can lead to 

chemical precipitation of iron hydroxides in aquifer material 

and can decrease the effective porosity. If ORP is less than 

250 mV, more reducing conditions may cause reduction of 

nitrate and dissolution of arsenic, iron, and manganese in aquifer materials, thereby leading to larger dissolved concentrations of these constituents in groundwater. Even more reducing conditions involve geochemical and biological processes 

that convert dissolved sulfate to hydrogen sulfide gas. As a 

result, highly reduced areas (small ORP values) are expected 

to have smaller dissolved sulfate or nitrate concentrations.

Average values for ORP measured in wells in the study 

area from 1995 through 2005 are shown in figure 10A for the 

shallow parts of the aquifer and in figure10B for the deep parts 

of the aquifer. Average ORP in the shallow parts of the aquifer 

indicated more reducing conditions (ORP less than 250 mV) 

along parts of Kisiwa Creek and the Little Arkansas River. In 

the deep parts of the aquifer, most of the southern part of the 

study area (Sedgwick County) was more oxidizing than the 

northern part (Harvey County). This generally corresponded 

to larger effective porosity values (more sandy material) in the 

southern part of the study area.

Major Ions

Dissolution of rocks and minerals is the primary source 

for most major ions in water (Hem, 1992). However, primary 

sources of chloride in the study area are from past oil and 

gas activities near Burrton, Kansas, the Arkansas River, and 

municipal wastewater and industrial discharges (Whittemore, 

2007). Major ion constituents analyzed in water samples collected for this study include calcium, magnesium, potassium, 

sodium, bicarbonate, carbonate, bromide, chloride, fluoride, 

and sulfate. Summaries of these constituent concentrations for 

the study area are presented in table A-4.

Groundwater in the Equus Beds aquifer is predominantly 

a calcium bicarbonate type, changing to a sodium chloride 

type in some areas (Leonard and Kleinschmidt, 1976). The 

groundwater near the Arkansas River is a calcium sodium 

chloride type. Farther away from the Arkansas River, the 

dominant groundwater is a calcium bicarbonate type.

Large concentrations of major ions are objectionable 

in drinking water because of possible physiological effects, 

unpalatable mineral tastes, and greater costs because of corrosion or the need for additional treatment (U.S. Environmental 

Protection Agency, 1986). The major ions that frequently 

exceeded water-quality criteria include sodium, sulfate, and 

chloride. Sulfate and chloride are discussed in detail because 

of the potential for saltwater migration from the Burrton oil 

field and the Arkansas River into the Equus Beds aquifer. 

Sulfate 

Sulfate is a major ion of importance for artificial 

recharge. Natural sources of sulfate in surface water and 

groundwater are rock weathering, oxidation of sulfide minerals, and biological processes. The primary anthropogenic 

(human-related) sources of sulfate in water are atmospheric 

deposition of the combustion of coal and petroleum products 
24 Water Quality in the Equus Beds Aquifer and the Little Arkansas River, South-Central Kansas 

Wichita

Newton

Maize

Sedgwick

Colwich

Mount Hope

Andale

0 1 2 3 4 5 MILES

0 1 2 3 4 5 KILOMETERS

Base from U.S. Geological Survey digital data, 1:100,000, 1983

Universal Transverse Mercator projection,

Zone 14

Horizontal coordinate information is referenced to the North American

 Datum of 1983 (NAD 83)

97°40'

38°

38°50’

38°05’

55’

35' 30' 97°25'

West Em

ma Creek

Middle Em

ma Creek

East Emma Creek

Em

ma Creek

Sand Creek

Jester Creek

Valley

Center

Little Arkansas River

Kisiwa Creek

Big Slough

Cowskin Creek

R. 3 W. R. 2 W. R. 1 W.

T.

26

S.

T.

25

S.

T.

24

S.

T.

23

S.

T.

22

S.

R. 4 W.

RENO COUNTY

SEDGWICK COUNTY

HARVEY COUNTY

Bentley

IW-38A

1,020 IW-37A

988 IW-36A

1,870 IW-35A

2,090

IW-34A563

IW-33A

568

IW-32A685

IW-31A

984 IW-30A

1,150

IW-29A

1,450

IW-28A905

IW-26A

IW-25A 682

878 IW-24A

922

IW-23A679 IW-22A886 IW-21A

1,000

IW-27A819

IW-20A

1,840 IW-19A

1,610

IW-18A

1,250

IW-16A

855

IW-17A889 IW-15A

1,360

IW-14A852

IW-10A

479

IW-09A

569

IW-08A

1,540

IW-13A

1,270

IW-07A

358

IW-06A

603 IW-05A

396

IW-03A512 IW-02A179

IW-01A

143

IW-11A-2 426

Black

Kettle Creek

Halstead

07144100

07143672

ARKANSAS

RIVER

778

760

363

532

679

800

201

183

1,080

1,860

1,560

1,360

1,130

560

588

506

669

444 1,820

1,280 2,060

114

574

652

895

302

292

906

867

962

1,200 1,590

1,090

1,190

1,700

1,820

1,140

3,270

1,520

643

694

611

896

768

613 567 632

768 683

779 1,140; 1,060; 1,020

1,020

640

500

1,000

1,000

2,000

1,000

1,000

1,000

2,000

2,000

500

Burrton

Boundary of study area

Boundary of study area

EXPLANATION

760

IW-04A

563

Little Arkansas River

IW-12A612

Average specific conductance, in microsiemens 

 per centimeter at 25 degrees Celsius

 Less than 500

 500 to less than 1,000

 1,000 to less than 2,000

 Equal to or greater than 2,000

Line of equal average specific conductance,

 1995–2005—Interval 500 and 1,000 microsiemens

 per centimeter at 25 degrees Celsius

Data collection sites

IW-38C 1,020

07144100

694 183

652

1,000

“EB” well (2002–05 data)—Number is average

 specific conductance concentration, in

 microsiemens per centimeter at 25 degrees

 Celsius

“P” well (2002–05 data)—Number is average

 specific conductance concentration, in

 microsiemens per centimeter at 25 degrees

 Celsius

834

“EB” and “P” data from Equus Bed Groundwater

 Management District No. 2 (Mike Dealy, Manager,

 written commun., 2006)

A. Shallow wells

Index well and site identifier (2001–05 data)—

 Lower number is average specific conductance

 concentration, in microsiemens per centimeter

 at 25 degrees Celsius

Recharge demonstration site (1995–2005 data)—

 Number is average specific conductance

 concentration, in microsiemens per centimeter

 at 25 degrees Celsius

Background well (1995–2005 data)—Number is

 average specific conductance concentration, in

 microsiemens per centimeter at 25 degrees

 Celsius U.S. Geological Survey streamflow-gaging

 station, continuous real-time water-quality

 monitoring site and site identifier

Figure 9. Average specific conductance in and near the study area, 1995–2005, in (A) shallow wells and (B) deep wells (“EB” and “P” 

well data for 2002–05 from Mike Dealy, Manager, Equus Beds Groundwater Management District No. 2, written commun., 2006).
Water Quality in the Equus Beds Aquifer and Little Arkansas River, 1995–2005 25

Wichita

Newton

Sedgwick

Colwich

Mount Hope

Andale

444

391

296

372 

373 384

 381

0 1 2 3 4 5 MILES

0 1 2 3 4 5 KILOMETERS

Base from U.S. Geological Survey digital data, 1:100,000, 1983

Universal Transverse Mercator projection,

Zone 14

Horizontal coordinate information is referenced to the North American

 Datum of 1983 (NAD 83)

97°40'

38°

38°50’

38°05’

55’

35' 30' 97°25'

West Em

ma Creek

Middle Em

ma Creek

East Emma Creek

Em

ma Creek

Sand Creek

Jester Creek

Valley

Center

Little Arkansas River

Kisiwa Creek

Big Slough

Cowskin Creek

R. 3 W. R. 2 W. R. 1 W.

T.

26

S.

T.

25

S.

T.

24

S.

T.

23

S.

T.

22

S.

R. 4 W.

RENO COUNTY SEDGWICK COUNTY

HARVEY COUNTY

Bentley

IW-38C 791 IW-37C

772 IW-36C

1,290 IW-35C

1,360

IW-34C 751

IW-33C

821

IW-32C 772

IW-31C 994 IW-30C

1,410

IW-29C

931

IW-28C

856

IW-26C

IW-25C 907

963 IW-24C

1,150

IW-23C 647 IW-22C 689 IW-21C

1,670

IW-27C

801

IW-20C

1,260 IW-19C 944

IW-18C

992

IW-16C

840

IW-17C

517 IW-15C

940

IW-14C

1,440

IW-10C

354

IW-09C

519

IW-08C

4,360

IW-13C

1,160

IW-07C

407

IW-06C

350 IW-05C

710

IW-03C 334 IW-02C 296

IW-01C

279

IW-11C 386

IW-12C

1,290

Black

Kettle Creek

Halstead

07144100

07143672

ARKANSAS

RIVER

229

222

1,090

3,880

2,460

1,350

2,420

2,210

1,860

1,180

814

1,100

2,320

1,070 406

207

278

323

736

942

299

782

1,320

804

1,110

3,980 2,460 375

1,030

290

3,300

4,280

584

1,760

792

746

639

698

651 771

Burrton

Boundary of study area

Boundary of study area

IW-04C

740 500

500

2,000

2,000

1,000

1,000

5,000

2,000

417 

376 

372

364

369

Little Arkansas River

5,590

Maize

B. Deep wells

EXPLANATION

 Less than 500

 500 to less than 1,000

 1,000 to less than 2,000

 Equal to or greater than 2,000

Approximate location of bedrock low

(McPherson channel)

Line of equal average specific conductance,

 1995–2005—Interval 500 and 1,000 microsiemens

 per centimeter at 25 degrees Celsius

Data collection sites

 IW-38C 791

07144100

639

229

804

391

1,000

“EB” well (2002–05 data)—Number is average

 specific conductance, in microsiemens per

 centimeter at 25 degrees Celsius

“P” well (2002–05 data)—Number is average

 specific conductance, in microsiemens per

 centimeter at 25 degrees Celsius

“EB” and “P” data from Equus Bed Groundwater

 Management District No. 2 (Mike Dealy, Manager,

 written commun., 2006)

Index well and site identifier (2001–05 data)—

 Lower number is average specific conductance,

 in microsiemens per centimeter at 25 degrees

 Celsius

Recharge demonstration site (1995–2005 data)—

 Number is average specific conductance, in

 microsiemens per centimeter at 25 degrees Celsius

Artificial storage and recovery prototype site

 (2002–05 data)—Number is average specific

 conductance, in microsiemens per centimeter

 at 25 degrees Celsius

U.S. Geological Survey streamflow-gaging

 station, continuous real-time water-quality

 monitoring site and site identifier

Average specific conductance, in microsiemens 

 per centimeter at 25 degrees Celsius

Figure 9. Average specific conductance in and near the study area, 1995–2005, in (A) shallow wells and (B) deep wells (“EB” and “P” well 

data for 2002–05 from Mike Dealy, Manager, Equus Beds Groundwater Management District No. 2, written commun., 2006).—Continued
26 Water Quality in the Equus Beds Aquifer and the Little Arkansas River, South-Central Kansas 

Wichita

Newton

Maize

Sedgwick

Colwich

Mount Hope

Andale

Hesston

Cowskin Creek

0 1 2 3 4 5 MILES

0 1 2 3 4 5 KILOMETERS

Base from U.S. Geological Survey digital data, 1:100,000, 1983

Universal Transverse Mercator projection,

Zone 14

Horizontal coordinate information is referenced to the North American

 Datum of 1983 (NAD 83)

97°40'

38°

38°50’

38°05’

55’

35' 30' 97°25'

Little Arkansas River

West Em

ma Creek

Middle Emma Creek

East Emma Creek

Em

ma Creek

Sand Creek

Jester Creek

Valley

Center

Little Arkansas River

Kisiwa Creek

Big Slough

T.

26

S.

T.

25

S.

T.

24

S.

T.

23

S.

T.

22

S.

R. 4 W. R. 3 W. R. 2 W. R. 1 W. RENO COUNTY SEDGWICK COUNTY

HARVEY COUNTY

Bentley

IW-38A253 IW-37A

487 IW-36A

537 IW-35A

503

IW-34A221

IW-33A

509

IW-32A454

IW-31A

509 IW-30A

539

IW-29A

141

IW-28A440

IW-26A

IW-25A 465

506 IW-24A

516

IW-23A129 IW-22A274 IW-21A

139

IW-27A503

IW-20A

169 IW-19A163

IW-18A

311

IW-16A

149

IW-17A180 IW-15A

129

IW-14A298

IW-10A

489

IW-09A

460

IW-08A

381

IW-13A

158

IW-07A

255

IW-06A

522 IW-05A

454

IW-03A200 IW-02A513

IW-01A

466

IW-11A-2 121

IW-12A376

Black

Kettle Creek

Halstead

07144100

07143672

EXPLANATION

Average oxidation-reduction potential, in millivolts

 Less than 250

 250 to less than 500

 Equal to or greater than 500

U.S. Geological Survey streamflow-gaging station,

 continuous real-time water-quality monitoring site

 and site identifier

Data-collection sites

 Index well and site identifier (2001–05 data)—Lower

 number is average oxidation-reduction potential, in millivolts

 Recharge demonstration site (1995–2005 data)—Number is

 average oxidation-reduction potential, in millivolts

 Background well (1995–2005 data)—Number is average

 oxidation-reduction potential, in millivolts

 Indicates not measured

IW-38A253

07144100

498

203

ARKANSAS RIVER

467

--

125

160

151

--

498

496

526

480

207

420 220 163

310

166

154; 126; 130

--

203

Burrton

Boundary of study area

Boundary of study area

IW-04A

357

-- 

A. Shallow wells

--

Figure 10. Average oxidation-reduction potential in the study area, 1995–2005, in (A) shallow wells and (B) deep wells.
Water Quality in the Equus Beds Aquifer and Little Arkansas River, 1995–2005 27

Wichita

Newton

Maize

Sedgwick

Colwich

Mount Hope

Andale

Hesston

334 

230

205

205

304

344 377

 228

193 

259 

269

235

230

0 1 2 3 4 5 MILES

0 1 2 3 4 5 KILOMETERS

Base from U.S. Geological Survey digital data, 1:100,000, 1983

Universal Transverse Mercator projection,

Zone 14

Horizontal coordinate information is referenced to the North American

 Datum of 1983 (NAD 83)

97°40'

38°

38°50’

38°05’

55’

35' 30' 97°25'

Little Arkansas River

West Em

ma Creek

Middle Emma Creek

East Emma Creek

Em

ma Creek

Sand Creek

Jester Creek

Valley

Center

Little Arkansas River

Kisiwa Creek

Big Slough

R. 3 W. R. 2 W. R. 1 W.

T.

26

S.

T.

25

S.

T.

24

S.

T.

23

S.

T.

22

S.

R. 4 W.

RENO COUNTY SEDGWICK COUNTY

HARVEY COUNTY

Bentley

IW-38C 349 IW-37C

409 IW-36C

495 IW-35C 471

IW-34C 374

IW-33C

391

IW-32C 408

IW-31C 331 IW-30C 447

IW-29C

126

IW-26C

412 IW-25C

436 IW-24C

479

IW-23C 179 IW-22C 123 IW-21C 118

IW-27C

316

IW-20C 133 IW-19C 194

IW-18C

171

IW-16C

153

IW-17C90 IW-15C

231

IW-14C 134

IW-10C

130

IW-09C

162

IW-08C

145

IW-13C

116

IW-07C

244

IW-06C

139 IW-05C 199

IW-03C 205 IW-02C 214

IW-01C

170

IW-11C 160

IW-12C 131

Black

Kettle Creek

Halstead

07144100

07143672

EXPLANATION

Average oxidation-reduction potential, in millivolts

 Less than 250

 250 to less than 500

Approximate location of bedrock low (McPherson channel)

U.S. Geological Survey streamflow-gaging station,

 continuous real-time water-quality monitoring site

 and site identifier

Data-collection sites

 Index well and site identifier (2001–05 data)—Lower

 number is average oxidation-reduction potential, in millivolts

 Recharge demonstration site (1995–2005 data)—Number is

 average oxidation-reduction potential, in millivolts

 Artificial storage and recovery prototype well

 (2002–05 data)—Number is average oxidation-reduction

 potential, in millivolts

IW-38C 349

07144100

405

ARKANSAS RIVER

405

180

433

143

147 189

Burrton

Boundary of study area

Boundary of study area

IW-04C 188

IW-28C

369

Cowskin Creek

B. Deep wells

Figure 10. Average oxidation-reduction potential in the study area, 1995–2005, in (A) shallow wells and (B) deep wells.—Continued
28 Water Quality in the Equus Beds Aquifer and the Little Arkansas River, South-Central Kansas 

and irrigation return flows. Sulfate contributes to the 

dissolved-solids concentrations in water and is considered 

undesirable when exceeding 250 mg/L according to the Federal SDWR established by the USEPA (U.S. Environmental 

Protection Agency, 2005). At concentrations exceeding the 

Federal SDWR, consumers start to notice odor, bitter taste, 

and a laxative effect.

Water samples collected from the Little Arkansas River 

near Halstead and near Sedgwick from 1995 through 2005 

had a median sulfate concentration of about 40 mg/L (table 

1), which was much less than the Federal SDWR (table 1). 

Sulfate concentrations ranged from about 5 to 312 mg/L. The 

Federal SDWR for sulfate was exceeded in less than 1 percent 

of the stream-water samples. Concentrations were less than the 

Federal SDWR for sulfate in all samples of the treated source 

water at the Sedgwick recharge site (table A-4).

Christensen and others (2000, 2003) developed a regression model to compute concentrations of sulfate in the Little 

Arkansas River on the basis of specific conductance of the 

stream water. This model was used to compute concentrations of sulfate in the Little Arkansas River for 1999 through 

2005. Data and regression models are available on the World 

Wide Web at http://nrtwq.usgs.gov/ks/. Computed sulfate 

concentrations in the Little Arkansas River from 1999 through 

2005 ranged from 3 to 93 mg/L near Halstead and from 2 to 

104 mg/L near Sedgwick. Computed median sulfate concentrations in the Little Arkansas River for this 7-year period 

were 45 mg/L near Halstead and near Sedgwick. The largest 

sulfate concentration computed at either surface-water site on 

the Little Arkansas River was 104 mg/L, much less than the 

Federal SDWR of 250 mg/L. The largest sampled concentrations at both surface-water sites were collected under complete 

ice cover and relative low-flow conditions that likely affected 

the concentrations in the water. The next largest concentrations sampled were about 90 mg/L, very similar to the largest 

computed concentrations, which demonstrated that, during 

typical streamflow and temperature conditions, the computed 

values describe sulfate conditions well, especially considering 

the more complete measurements on an hourly basis (8,760 

values per year) of specific conductance compared to samples 

collected less than 20 times per year.

The distribution of average sulfate concentrations in 

groundwater in the study area is shown in figure 11. The areas 

shown in figure 11 indicate that about 11 percent of the shallow parts of the aquifer and about 9 percent of the deep parts 

of the aquifer have average sulfate concentrations exceeding 

the Federal SDWR. In the shallow parts of the aquifer, average 

concentrations of sulfate in water samples from 18 percent of 

the wells exceeded the Federal SDWR (table 2). These wells 

are located mostly near the center of the study area (fig. 11A; 

wells IW-08A, 15A, 16A, 19A, 20A, 21A, and 29A). The 

average concentration of sulfate in the shallow parts of the 

aquifer exceeded 500 mg/L in water from well IW-20A. In the 

deep parts of the aquifer, water samples from 13 percent of the 

index wells had average sulfate concentrations that exceeded 

250 mg/L (table 2). The average sulfate concentration in the 

deep parts of the aquifer exceeds 500 mg/L in water from well 

IW-21C (fig. 11B). Those wells with average sulfate concentrations exceeding SWDR are located along Kisiwa Creek 

where the aquifer is thickest (figs. 5 and 7) and generally 

are associated with areas of the aquifer that were dewatered 

(through 1992) and have subsequently recovered (fig. 4).

Hathaway and others (1981) reported that sulfate concentrations during 1979 through 1980 of less than 50 mg/L 

occurred in shallow groundwater in the northern part of the 

study area. Concentrations of more than 50 mg/L occurred 

in the middle and southern parts of the study area and near 

Burrton, with isolated areas of concentrations larger than 120 

mg/L occurring near Burrton, along the Arkansas River, and 

near or south of Kisiwa Creek. This pattern of sulfate concentrations as compared with those in figure 11A indicates 

that sulfate concentrations in the Equus Beds aquifer have 

increased in the past 20 years. These changes likely were 

caused by dewatering of the aquifer material and subsequent 

oxidation that resulted in increased sulfate concentrations as 

water levels increased since 1992. 

Sulfate is a charged ionic species that increases the 

specific conductance of water (Hem, 1992). An increase in 

sulfate concentration results in a corresponding increase in 

specific conductance in both surface and groundwater. Sulfur 

concentrations also can be strongly related to oxidation-reduction properties of water (Hem, 1992); however, in the study 

described herein, statistical analysis of ORP was not shown to 

be strongly related to sulfate in the Equus Beds aquifer.

Regression plots showing the statistical relation between 

specific conductance and sulfate concentrations are shown for 

shallow index wells (fig. 12A), deep index wells (fig. 12B), 

and the average of shallow and deep wells at each index well 

site (fig. 12C). The regression models and their respective 

coefficients of determination (R2

) and root mean square errors 

(RMSE) for figures 12A-C follow:

Shallow index wells: 

sulfate = 0.0074 specific conductance1.414; 

R2 = 0.583; RMSE = 116;

Deep index wells: 

sulfate = 0.0123 specific conductance1.276; 

R2 = 0.466; RMSE = 142; and

Combined shallow and deep index wells: 

sulfate = 0.0103 specific conductance1.334

R2 = 0.501; RMSE = 146;

where sulfate is in milligrams per liter and specific conductance is in microsiemens per centimeter at 25 degrees Celsius. 

The coefficients of determination for these regressions indicate 

that specific conductance explains about 50 percent of the 

variability in sulfate concentrations in groundwater and is an 

acceptable predictor of sulfate in groundwater. 
Water Quality in the Equus Beds Aquifer and Little Arkansas River, 1995–2005 29

Wichita

Newton

Maize

Sedgwick

Colwich

Mount Hope

Andale

Hesston

A. Shallow wells

0 1 2 3 4 5 MILES

0 1 2 3 4 5 KILOMETERS

Base from U.S. Geological Survey digital data, 1:100,000, 1983

Universal Transverse Mercator projection,

Zone 14

Horizontal coordinate information is referenced to the North American

 Datum of 1983 (NAD 83)

97°40'

38°

38°50’

38°05’

55’

35' 30' 97°25'

Little Arkansas River

West Em

ma Creek

Middle Emma Creek

East Emma Creek

Em

ma Creek

Sand Creek

Jester Creek

Valley

Center

Little Arkansas River

Kisiwa Creek

Big Slough

Cowskin Creek

R. 3 W. R. 2 W. R. 1 W.

T.

26

S.

T.

25

S.

T.

24

S.

T.

23

S.

T.

22

S.

R. 4 W.

RENO COUNTY SEDGWICK COUNTY

HARVEY COUNTY

Bentley

IW-38A218 IW-37A

57 IW-36A

180 IW-35A

177

IW-34A110

IW-33A

44

IW-32A84

IW-31A

69 IW-30A

114

IW-29A

445

IW-28A247

IW-26A

IW-25A 49

87 IW-24A

66

IW-23A72 IW-22A163 IW-21A

280

IW-27A135

IW-20A

620 IW-19A317

IW-18A

170

IW-16A

288

IW-17A139 IW-15A

456

IW-14A210

IW-10A

38

IW-09A

109

IW-08A

370

IW-13A

201

IW-07A

16

IW-06A

46 IW-05A

30

IW-03A32 IW-02A41

IW-01A

17

IW-11A-29

Black

Kettle Creek

Halstead

07144100

07143672

EXPLANATION

Average sulfate concentrations, in milligrams

 per liter

 Less than 50

 50 to less than 100

 100 to less than 250

U.S. Geological Survey streamflow-gaging

 station, continuous real-time water-quality

 monitoring site and site identifier

Data-collection sites

 Index well and site identifier (2001–05 data)—Lower

 number is average sulfate concentration, in milligrams

 per liter

 Recharge demonstration site (1995–2005 data)—Number

 is average sulfate concentration, in milligrams per liter

 Background well (1995–2005 data)—Number is average

 sulfate concentration, in milligrams per liter

IW-15A456

07144100

86

37

ARKANSAS RIVER

50

186

10

54

37

74

75

52

86

60

72

56 45 56

61 53

87 39; 6; 8

81

100

Burrton

Boundary of study area

Boundary of study area

IW-04A

15

250 to less than 500

Equal to or greater

 than 500 

Note: U.S. Environmental Protection Agency (2006a) Secondary Drinking-Water

 Regulation for sulfate is 250 milligrams per liter

IW-12A74

Figure 11. Average sulfate concentrations in the study area, 1995–2005, in (A) shallow wells and (B) deep wells.
30 Water Quality in the Equus Beds Aquifer and the Little Arkansas River, South-Central Kansas 

Wichita

Newton

Maize

Sedgwick

Colwich

Mount Hope

Andale

18

25

13

10

 15 15 

15

13

15

35 

15 16

13

0 1 2 3 4 5 MILES

0 1 2 3 4 5 KILOMETERS

Base from U.S. Geological Survey digital data, 1:100,000, 1983

Universal Transverse Mercator projection,

Zone 14

Horizontal coordinate information is referenced to the North American

 Datum of 1983 (NAD 83)

97°40'

38°

38°50’

38°05’

55’

35' 30' 97°25'

West Em

ma Creek

Middle Emma Creek

East Emma Creek

Em

ma Creek

Sand Creek

Jester Creek

Valley

Center

Little Arkansas River

Kisiwa Creek

Big Slough

Cowskin Creek

R. 3 W. R. 2 W. R. 1 W.

T.

26

S.

T.

25

S.

T.

24

S.

T.

23

S.

T.

22

S.

R. 4 W.

RENO COUNTY SEDGWICK COUNTY

HARVEY COUNTY

Bentley

IW-38C 110 IW-37C

46 IW-36C

96 IW-35C75

IW-34C51

IW-33C

70

IW-32C51

IW-31C 102 IW-30C 286

IW-29C

172

IW-26C

65 IW-25C

77 IW-24C

77

IW-23C50 IW-22C83 IW-21C 505

IW-27C

59

IW-20C 375 IW-19C73

IW-18C

84

IW-16C

267

IW-17C41 IW-15C

186

IW-14C 328

IW-10C

26

IW-09C

26

IW-08C

47

IW-13C

116

IW-07C

38

IW-06C

11 IW-05C19

IW-03C13 IW-02C10

IW-01C

6

IW-11C17

IW-12C 236

Black

Kettle Creek

Halstead

07144100

07143672

ARKANSAS RIVER

50

66

51

59

36 58

Burrton

Boundary of study area

Boundary of study area

IW-04C18

IW-28C

60

EXPLANATION

Average sulfate concentrations, in milligrams

 per liter

 Less than 50

 50 to less than 100

 100 to less than 250

Approximate location of bedrock low

 (McPherson channel)

U.S. Geological Survey streamflow-gaging

 station, continuous real-time water-quality

 monitoring site and site identifier

Data collection sites

 Index well and site identifier (2001–05 data)—Lower

 number is average sulfate concentration, in milligrams

 per liter

 Recharge demonstration site (1995–2005 data)—Number

 is average sulfate concentration, in milligrams per liter

 Artificial storage and recovery prototype well

 (2002–05 data)—Number is average sulfate concentration,

 in milligrams per liter

IW-15C 186

07144100

51

250 to less than 500

Equal to or greater

 than 500 

Little Arkansas River

Note: U.S. Environmental Protection Agency (2006a) Secondary Drinking-Water

 Regulation for sulfate is 250 milligrams per liter

B. Deep wells

Figure 11. Average sulfate concentrations in the study area, 1995–2005, in (A) shallow wells and (B) deep wells.—Continued
Water Quality in the Equus Beds Aquifer and Little Arkansas River, 1995–2005 31

SO4 = 0.0103SC 1.334

R2 = 0.501

RMSE = 146

SO4

 = 0.0123SC 1.276

R2 = 0.466

RMSE = 142

SO4

 = 0.0074SC1.414

R2 = 0.583

RMSE = 116 Shallow index well

Shallow index well

Deep index well

Deep index well

0 500 1,000 1,500 2,000 2,500 3,000 3,500 4,000 4,500 5,000

0

200

100

400

300

600

500

700

800

900

1,000

0

200

100

300

500

700

400

600

800

900

1,000

0

200

100

300

500

700

400

600

800

900

1,000

C. Combined shallow and deep index wells

B. Deep index wells

A. Shallow index wells

SULFATE (SO4) CONCENTRATION IN SHALLOW AND DEEP INDEX WELLS, IN MILLIGRAMS PER LITER

SPECIFIC CONDUCTANCE (SC), IN MICROSIEMENS PER CENTIMETER AT 25 DEGREES CELSIUS

R2 = coefficient of determination

RMSE = root mean square error

Figure 12. Statistical relation between specific conductance and sulfate concentrations in (A) shallow index wells, (B) deep index 

wells, and (C) combined shallow and deep index wells.
32 Water Quality in the Equus Beds Aquifer and the Little Arkansas River, South-Central Kansas 

Chloride

Sources of chloride in the Equus Beds aquifer include 

underlying rocks and past disposal of oil-field brines. Natural 

water from the unconsolidated aquifer normally contains less 

than 100 mg/L chloride, whereas larger concentrations (100 

to 500 mg/L) are common in the western part of the study 

area near the Burrton oil field and along the Arkansas River. 

Chloride concentrations in the Arkansas River averaged about 

600 mg/L from 1988 through 1991 (Myers and others, 1996). 

From 1997 through 2006, concentrations of chloride in the 

Arkansas River between Hutchison and Maize averaged about 

500 mg/L (Kansas Department of Health and Environment, 

2006a). Upwelling of brines from the underlying Permian salt 

beds enter tributaries upstream from Hutchison, Kansas that 

flow into the Arkansas River (Kansas Department of Health 

and Environment, 2006a; Whittemore, 2007). From 1985 

through 2005, chloride concentrations averaged 267 mg/L in 

the Little Arkansas River near Alta Mills, Kansas (upstream 

of Halstead) (Kansas Department of Health and Environment, 2006b). Sources of chloride in the Little Arkansas River 

include contamination from past oil and gas activities near 

McPherson and municipal and industrial wastewater discharges (Leonard and Kleinschmidt, 1976; Kansas Department 

of Health and Environment, 2006b; Schmidt and others, 2007; 

Whittemore, 2007).

The USEPA established a Federal SDWR of 250 mg/L for 

chloride (U.S. Environmental Protection Agency, 1986). Constituents listed under the Federal SDWRs do not create health 

issues for humans, but limits are set for aesthetic reasons, such 

as taste and odor. When chloride concentrations are larger than 

250 mg/L, consumers notice a bleach odor and salty taste in 

the water. In addition, large concentrations of chloride also can 

contribute to corrosion and staining of plumbing and fixtures 

(U.S. Environmental Protection Agency, 2005). Irrigation 

water with concentrations exceeding 350 mg/L chloride is 

likely to cause severe effects on crops (Bauder and others, 

2007).

Water samples collected at the two surface-water sites 

on the Little Arkansas River from 1995 through 2005 had a 

median chloride concentration of 91 mg/L, which is less than 

the Federal SDWR for chloride of 250 mg/L (table 1). Chloride concentrations in water samples collected from the Little 

Arkansas River near Halstead and near Sedgwick ranged from 

5 to 932 mg/L. The Federal SDWR for chloride was exceeded 

in about 14 percent of the samples collected from the two 

surface-water monitoring sites on the Little Arkansas River 

during 1995 through 2005 (table 1). Chloride concentrations 

were less than the Federal SDWR for all samples of the treated 

water at the Sedgwick recharge site (table A-4).

Continuous real-time chloride concentrations in the 

Little Arkansas River were computed on the basis of specific 

conductance measurements using regression models from 

Christensen and others (2003) for the period 1999 through 

2005. Duration curves indicated that during 1999 through 

2005, the median computed chloride concentration was 180 

mg/L in the Little Arkansas River near Halstead and exceeded 

250 mg/L about 27 percent of the time (fig. 13). The median 

computed chloride concentration in the Little Arkansas 

River near Sedgwick from 1999 through 2005 was about 94 

mg/L and exceeded 250 mg/L less than 1 percent of the time 

(fig 13). Larger specific conductance and chloride concentrations generally correspond with low-flow conditions. Chloride 

concentrations likely are smaller at the downstream Sedgwick 

site because of dilution from groundwater inflow containing 

smaller chloride concentrations.

In groundwater, the 1995–2005 average concentrations 

of chloride exceeded 250 mg/L in water samples from about 5 

percent of the index wells in the shallow parts of the aquifer (table 2). Shallow wells with average concentrations of 

chloride larger than 250 mg/L are near Burrton and along the 

Arkansas River (fig. 14A). Average chloride concentrations in 

the shallow parts of the Equus Beds aquifer for 1995 through 

2005 along with additional data gathered by GMD2 from 2002 

through 2005 are shown in figure 14A. This map shows that 

about 7 percent of the shallow parts of the aquifer in the study 

area had average concentrations of chloride exceeding 250 

mg/L from 1995 through 2005. Comparison of 1995–2005 

concentrations to those of 1989-90 published by Myers and 

others (1996) indicates that chloride concentrations in the 

southern part of the study area along the Arkansas River have 

not changed substantially. In the area east of Burrton, chloride 

concentrations larger than 500 mf/L in the shallow parts of the 

aquifer have moved slightly less than 0.5 mi farther into the 

study area compared to 1982–84. 

Average chloride concentrations in the deep parts of the 

Equus Beds aquifer are shown in figure 14B. Average chloride 

concentrations exceeded 250 mg/L in water samples from 

about 5 percent of the index wells (table 2). As was the case 

in the shallow parts of the aquifer, concentrations exceeding 

250 mg/L were detected in wells located near Burrton and 

along the Arkansas River. About 8 percent of the deep parts 

of the aquifer in the study area had average chloride concentrations that exceeded the Federal SDWR for 1995–2005. 

Average chloride concentrations for 1989-90 from Myers and 

others (1996) indicate that concentrations in the deep parts of 

the aquifer were larger near the Arkansas River than during 

1995–2005. 

The area near Burrton with average chloride concentrations exceeding 500 mg/L is larger in the deep parts of the 

aquifer than it is in the shallow parts (fig. 14). This difference 

is likely caused by the downward migration of saltwater from 

disposal brines in surface pits during 1910-40s (Whittemore, 

2007). Larger chloride concentrations in the deep parts of the 

aquifer also could be caused by upward movement of saltwater 

through natural fractures in the bedrock or wells, or could be 

the result of infiltration of dilute rainfall and the greater density of saltwater than freshwater (Leonard and Kleinschmidt, 

1976). Additional sources of chloride include the Arkansas 

River and Burrton oil-field brines that were recharged into the 

aquifer through shallow disposal wells and pits before these 

disposal practices were banned. Whittemore (2007) attributes 
Water Quality in the Equus Beds Aquifer and Little Arkansas River, 1995–2005 33

the larger chloride concentrations in the deeper parts of the 

aquifer near Burrton to the migration of dense oil-field brines 

into the deeper parts of the aquifer. Whittemore (2007) also 

concludes it will take many centuries for this deep saltwater to 

be flushed from the aquifer. 

A decrease in water-level gradient in the aquifer slows the 

movement of water and constituents in the aquifer. Water levels in the study area increased as compared to lows recorded 

in October 1992 because of larger than average precipitation, 

decreased pumping from the aquifer for Wichita supply, and 

increased use of Cheney Reservoir for municipal supplies. The 

increase in water levels decreased the gradient near Burrton 

from about 12 ft/mi in October 1992 to about 8 ft/mi in January 2006, slowing the migration of saltwater from the Burrton 

area into the aquifer (figs. 3 and 5). Along the Arkansas River 

near Bentley, the gradient decreased from about 8 ft/mi in 

October 1992 to about 6 ft/mi in January 2006.

Generally, during the past 40-45 years (since about 1960), 

chloride concentrations in both the shallow and deep parts of 

the aquifer have increased, migrating southward and eastward 

from the Burrton area about 3 mi. In the shallow parts of the 

aquifer, chloride concentrations have migrated eastward less 

that 0.5 mi since 1992 and have slowed at least partly because 

of the decreased hydraulic gradient in the aquifer. A more 

detailed description of the movement of chloride concentrations is provided in the following paragraphs. 

The graphs of chloride concentrations during 1939 

through 2005 shown in figure 15B indicate both the changes 

in chloride concentrations through time and the differences 

in chloride concentrations in the shallow and deep parts of 

the aquifer. Chloride concentrations to the west of Burrton 

decreased or remained stable in well clusters EB-5, EB-43, 

and EB-44, whereas in well clusters EB-1 and P-26 chloride 

concentrations increased to concentrations exceeding the 

Federal SDWR of 250 mg/L. This indicates some southward movement of the Burrton oil-field brines or possibly 

infiltration of water with larger chloride concentrations from 

the Arkansas River. Most of the wells have larger chloride 

concentrations in the deep wells than in the shallow wells. 

However, in well cluster EB-5, the largest chloride concentrations are in the shallow parts of the aquifer (55-ft depth) with 

smaller concentrations both above (18-ft depth) and below 

(180-ft depth). This indicates that less permeable clay layers 

are preventing the more dense water with the larger chloride 

concentrations in well EB-5A from moving to the deeper parts 

of the aquifer. 

Well cluster P-31 is near the center of the area with the 

largest concentrations near Burrton, presumably where the 

U.S. Environmental Protection Agency (2006a) Secondary Drinking Water Regulation (250 milligrams per liter) 

0

100

200

300

400

500

COMPUTED DISSOLVED CHLORIDE CONCENTRATION, IN MILLIGRAMS PER LITER

0 20 40 60 80 100

07143672 Little Arkansas River at Highway 50 near Halstead, Kansas

07144100 Little Arkansas River near Sedgwick, Kansas

PERCENTAGE OF TIME INDICATED VALUE WAS EQUALLED OR EXCEEDED

Figure 13. Duration curves of computed dissolved chloride concentrations, 1995–2005, Little Arkansas River near Halstead and near 

Sedgwick, Kansas.
34 Water Quality in the Equus Beds Aquifer and the Little Arkansas River, South-Central Kansas 

Newton

Sedgwick

97°40'

38°

38°50’

38°05’

55’

35' 30' 97°25'

West Em

ma Creek

Middle Em

ma Creek

East Emma Creek

Em

ma Creek

Sand Creek

Jester Creek

Valley

Center

Kisiwa Creek

Big Slough

Cowskin Creek

T.

26

S.

T.

25

S.

T.

24

S.

T.

23

S.

T.

22

S.

RENO COUNTY

SEDGWICK COUNTY

HARVEY COUNTY

Bentley

IW-38A17

IW-37A

110 IW-36A386

IW-35A428

IW-34A23

IW-33A

7

IW-32A39

IW-31A IW-30A 136 165

IW-29A

27

IW-28A28

IW-26A

11

IW-25A54

IW-24A

97

IW-23A15 IW-22A28 IW-21A

52

IW-27A24

IW-20A

82 IW-19A153

IW-18A

140

IW-16A

16

IW-17A10 IW-15A

73

IW-14A66

IW-10A

52

IW-09A15

IW-08A

146

IW-13A

131

IW-07A

9

IW-06A

46 IW-05A

43

IW-03A17 IW-02A8

IW-01A

8

IW-11A-210

Black

Kettle Creek

Halstead

17

18

5

8

28

35

5

7

119

492

324

161

100

100

100

100

250

250

500

500

50

50

50

100

50

50

140

54

31

32

74

43

63 472

308 678

3

187

139

91

4

40

206

48

85

147 75

132

478

587

204

1,020

195

45

50

48

105

33

16 14 23

42 37

30 135; 162; 156

26

30

Burrton

Boundary of study area

Boundary of study area

IW-04A

58

Little Arkansas River

IW-12A18 322

Area of map in figure 15

Mount Hope

250

250

100

50

500

250

250

500

500

R. 4 W. R. 3 W. R. 2 W. R. 1 W.

ARKANSAS RIVER

Little Arkansas River 07144100

07143672

RRW-1

RRW-2

RRW-3

RB-1

RB-2

EXPLANATION

18

Average chloride concentrations 1995–2005, in milligrams per liter

 Less than 50

 50 to less than 100

 100 to less than 250

Data-collection sites

 Index well and site identifier (2001–05 data)—Lower number

 is average chloride concentration, in milligrams per liter

 Recharge demonstration site (1995–2005 data)—Number is 

 average chloride concentration, in milligrams per liter

 Background well (1995–2005 data)—Number is average chloride

 concentration, in milligrams per liter

 “EB” well (2002–05 data)—Number is average chloride 

 concentration, in milligrams per liter

 “P” well (2002–05 data)—Number is average chloride 

 concentration, in milligrams per liter

 “EB” and “P” data from Equus Bed Groundwater Management District No. 2 (Mike Dealy, Manager,

 written commun., 2006)

Phase I recharge well or basin and site identifier

IW-38A17

45.2

119

132

250

Line of equal chloride concentration—Interval 50, 150, and 250

 milligrams per liter. Dashed where approximately located

 1982–84 (modified from Whittemore, 2007)

 1986–90 (modified from Myers and others, 1996)

 1995–2005

250 to less than 500

Equal to or greater than 500

Average chloride concentrations 1989–90, in milligrams per liter

 (modified from Myers and others, 1996)

 50 to less than 100

 100 to less than 250

250 to less than 500

Equal to or greater than 500

Average chloride concentrations 1982–84, in milligrams per liter

 (modified from Whittemore, 2007)

 250 to less than 500

 Equal to or greater than 500

250

250

07144100

RB-2

RRW-4

Base from U.S. Geological Survey digital data, 1:100,000, 1983

Universal Transverse Mercator projection,

Zone 14

Horizontal coordinate information is referenced to the North American

 Datum of 1983 (NAD 83)

0 1 2 3 4 5 MILES

0 1 2 3 4 5 KILOMETERS

Note: U.S. Environmental Protection Agency (2006a) Secondary Drinking-Water

 Regulation for chloride is 250 milligrams per liter

A. Shallow wells

U.S. Geological Survey streamflow-gaging station, continuous

 real-time water-quality monitoring site and site identifier

Figure 14. Average chloride concentrations in and near the study area, 1982–84, 1989–90, and 1995–2005, for (A) shallow wells and 

(B) deep wells (“EB” and “P” well data from Mike Dealy, Manager, Equus Beds Groundwater Management District No. 2, written 

commun. 2006; 1982–84 lines of equal chloride concentration modified from Whittemore and others, 2007; 1989–90 lines of equal chloride 

concentration modified from Myers and others, 1996).
Water Quality in the Equus Beds Aquifer and Little Arkansas River, 1995–2005 35

 7 Newton

Sedgwick

Boundary of study area

97°40'

38°

38°50’

38°05’

55’

35' 30' 97°25'

West Em

ma Creek

Middle Em

ma Creek

East Emma Creek

Em

ma Creek

Sand Creek

Jester Creek

Valley

Center

Kisiwa Creek

T.

26

S.

T.

25

S.

T.

24

S.

T.

23

S.

T.

22

S.

RENO COUNTY

SEDGWICK COUNTY

HARVEY COUNTY

Bentley

IW-38C26 IW-37C68 IW-36C

215

IW-35C 286

IW-34C52

IW-33C

61

IW-32C62

IW-31C 119 IW-30C

211

IW-29C

43

IW-28C

74

IW-26C IW-25C 92 94.9 IW-24C

189

IW-23C30 IW-22C21 IW-21C

110

IW-27C

59

IW-20C59 IW-19C 105

IW-18C

116

IW-16C

19

IW-17C12 IW-15C

78

IW-14C 123

IW-10C

17

IW-09C37

IW-08C

1,270

IW-13C

155

IW-07C

10

IW-06C

9 IW-05C

138

IW-03C7 IW-02C6

IW-01C

<5

IW-11C8

Black Kettle Creek

Halstead

4

5

145

1,180

796

192

250

250

100

100

50

50

500

500

643

528

123

250

115

130

2,180 660

111 51

4

144

108

6

4

139

304

58

148

1,290 11

134

7

1,080

1,320

15

344

62

52

27

50 Burrton

IW-04C 119

Little Arkansas River IW-12C77 644

Area of map in figure 15

250

250

500

500

R. 4 W. R. 3 W. R. 2 W. R. 1 W.

Cowskin Creek

ARKANSAS RIVER

Big Slough

Little Arkansas River

Mount Hope

250

500

1,000

250

250

500

500

1,000

1,000

2,000

50

43

8

5

<5 

7

 6

52 56

7 

6 

7

7

6

7

5

Boundary of study area

0 1 2 3 4 5 MILES

0 1 2 3 4 5 KILOMETERS

B. Deep wells

Base from U.S. Geological Survey digital data, 1:100,000, 1983

Universal Transverse Mercator projection,

Zone 14

Horizontal coordinate information is referenced to the North American

 Datum of 1983 (NAD 83)

EXPLANATION

Average chloride concentrations 1995–2005, in milligrams per liter

 Less than 50

 50 to less than 100

 100 to less than 250

Data-collection sites

 Index well and site identifier (2001–05 data)—Lower number

 is average chloride concentration, in milligrams per liter

 Recharge demonstration site (1995–2005 data)—Number is 

 average chloride concentration, in milligrams per liter

 Artificial storage and recovery prototype well

 (2002–05 data)—Number is average chloride

 concentration, in milligrams per liter

 “EB” well (2002–05 data)—Number is average chloride 

 concentration, in milligrams per liter

 “P” well (2002–05 data)—Number is average chloride 

 concentration, in milligrams per liter

 “EB” and “P” data from Equus Bed Groundwater Management District No. 2 (Mike Dealy, Manager,

 written commun., 2006)

Phase I recharge well or basin and site identifier

IW-38C26

62

140

130

250

Line of equal chloride concentration—Interval 50, 150, 200, 250,

 500, and 1,000 milligrams per liter

 1982–84 (modified from Whittemore, 2007)

 1986–90 (modified from Myers and others, 1996)

 1995–2005

250 to less than 500

Equal to or greater than 500

Average chloride concentrations 1989–90, in milligrams per liter

 (modified from Myers and others, 1996)

1,000 to less than 2,000

Equal to or greater than 2,000

Average chloride concentrations 1982–84, in milligrams per liter

 (modified from Whittemore, 2007)

 250 to less than 500

 Equal to or greater than 500

250

250

07144100

RB-2

Note: U.S. Environmental Protection Agency (2006a) Secondary Drinking-Water

 Regulation for chloride is 250 milligrams per liter

U.S. Geological Survey streamflow-gaging station, continuous

 real-time water-quality monitoring site and site identifier

50 to less than 250

250 to less than 500

500 to less than 1,000

RRW-1

RRW-2

RRW-3

RB-1

RB-2

RRW-4

07144100

07143672

Figure 14. Average chloride concentrations in and near the study area, 1982–84, 1989–90, and 1995–2005, for (A) shallow wells and 

(B) deep wells (“EB” and “P” well data from Mike Dealy, Manager, Equus Beds Groundwater Management District No. 2, written 

commun. 2006; 1982–84 lines of equal chloride concentration modified from Whittemore and others, 2007; 1989–90 lines of equal chloride 

concentration modified from Myers and others, 1996).—Continued
36 Water Quality in the Equus Beds Aquifer and the Little Arkansas River, South-Central Kansas 

250

500

250

500

100

50

50

100

500

250

97°42'30'' 40' 97°37'30''

38°

38°02'30''

37°57'30''

R. 4 W. R. 3 W.

T.

24

S.

T.

23

S.

HARVEY

COUNTY

RENO

COUNTY

IW-14

IW-14

IW-09

IW-08

IW-13

IW-05

IW-04

IW-02

P-35

P-32

P-30

P-28

P-28

P-27

P-26

P-31

EB-9

EB-8

EB-5

EB-2

EB-56

EB-20

EB-19

EB-17

EB-15

EB-14

EB-13

EB-13

EB-12

EB-11

EB-10

EB-21

EB-58

EB-44

EB-43

EB-1

EB-4 EB-57 EB-16

EB-3

EB-7

RB-2

RB-1

RB-1

RRW-3

RRW-4

RRW-2

RRW-1

Burrton

Base from U.S. Geological Survey digital data, 1:100,000, 1983

Universal Transverse Mercator projection,

Zone 14

Horizontal coordinate information is referenced to the North American

 Datum of 1983 (NAD 83)

97°42'30'' 40' 97°37'30''

38°

38°02'30''

37°57'30''

R. 4 W. R. 3 W.

T.

24

S.

T.

23

S.

HARVEY

COUNTY

RENO

COUNTY

IW-14

IW-09

IW-08

IW-13

IW-05

IW-04

IW-02

P-35

P-32

P-30

P-28

P-27

P-26

P-31

EB-9

EB-8

EB-2

EB-56

EB-20

EB-19

EB-17

EB-15

EB-14

EB-13

EB-12

EB-11

EB-21

EB-58

EB-44 

EB-43

EB-1

EB-4 EB-57

EB-16

EB-3

EB-7

RB-2

RB-1

RRW-3

RRW-4

RRW-2

RRW-1

Burrton

0 1 2 MILES

0 1 2 KILOMETERS

0 1 2 MILES

0 1 2 KILOMETERS

Well clusters

P-29

IW-14

P-28

EB-13

RB-1

Base from U.S. Geological Survey digital data, 1:100,000, 1983

Universal Transverse Mercator projection,

Zone 14

Horizontal coordinate information is referenced to the North American

 Datum of 1983 (NAD 83)

EB-5 EB-10

100

500

Boundary of

study area

P-29

Area enlarged from figures 14A and 14B

Area enlarged from figures 14A and 14B

Well clusters and section locations

A ́

A

G

H

J

K

K ́

I

B C

D E F

B ́

C ́ D ́

E ́

F ́

J ́

I ́

H ́

G ́

A ́A

K ́K

Study area

North-south cross section

East-west cross section

Index well cluster and cluster identifier

Phase I recharge well or basin and

 site identifier

“EB” well and cluster identifier

 (2002–05 data)

“P” well and cluster identifier

 (2002–05 data)

EXPLANATION

Average chloride concentration in deep wells, 1995–2005,

 in milligrams per liter

 Less than 50

 50 to less than 100

 100 to less than 250

Approximate location of bedrock low

(McPherson channel)

Line of average equal chloride concentration

 1995–2005, in milligrams per liter

Line of average equal chloride concentration

 1982–84, in milligrams per liter

 (modified from Whittemore, 2007)

Index well cluster and cluster identifier

Phase I recharge well or basin and

 site identifier

“EB” well cluster and cluster identifier

 (2002–05 data)

“P” well cluster and cluster identifier

 (2002–05 data)

EXPLANATION

250 to less than 500

Equal to or greater than 500 

Boundary of

study area

Boundary of study area

Note: U.S. Environmental Protection Agency (2006a) Secondary Drinking-

 Water Regulation for chloride is 250 milligrams per liter

Figure 15. Changes in chloride concentrations in the Equus Beds aquifer near Burrton, Kansas, during 1939–2005 (“EB” well and 

recent “P” well chloride concentration data from Mike Dealy, Manager, Equus Beds Groundwater Management District No. 2, 

written commun. 2006).
Water Quality of the Equus Beds Aquifer and Little Arkansas River, 1995–2005 37

Figure 15. Changes in chloride concentrations in the Equus Beds aquifer near Burrton, Kansas, during 1939–2005 (“EB” well and 

recent “P” well chloride concentration data from Mike Dealy, Manager, Equus Beds Groundwater Management District No. 2, 

written commun. 2006).—Continued (This figure is oversized, access by clicking here.)
38 Water Quality in the Equus Beds Aquifer and the Little Arkansas River, South-Central Kansas 

 BLANK PAGE
Water Quality in the Equus Beds Aquifer and Little Arkansas River, 1995–2005 39

oil-field brine contamination began. Chloride concentrations 

in well cluster P-31 increased from about 10 mg/L in 1948 

to almost 10,000 mg/L in 1950 and then rapidly decreased to 

about 1,000 mg/L in 1957 and remain at about 1,000 mg/L in 

well P31A (68-ft depth) in 2005. The decrease in concentrations in the more shallow well P31 (40-ft depth) and increase 

in the deeper well P31A indicate that the more dense oil-field 

brine migrated through the shallow part of the aquifer into the 

deep part. The deeper wells in well clusters P-31, P-30, P-29, 

and P-28 show the southward and eastward movement of the 

brines from the Burrton area—arriving at well P-31A in the 

mid- to late-1940s, at well P-30A in the mid-1950s, at well 

P-29A in the mid-1960s, and at well P-28A in the early 1990s. 

Although chloride concentrations decreased in shallow well 

P-31 since the mid-1950s, concentrations remained above the 

Federal SDWR. In shallow wells P-28, P-29, and P-30, the 

chloride concentrations have increased but not as much as 

in the deeper well in each cluster. Chloride concentrations in 

these shallow wells have approached or exceeded the Federal 

SDWR in recent years. During the early 1940s, chloride concentrations in well clusters P-26, P-28, and P-35 were about 

100 mg/L, but only about 10 mg/L in well clusters P-29, P-31, 

and P-32. 

Infiltration of water with larger chloride concentrations 

(about 500-600 mg/L) from the Arkansas River is the likely 

source of larger chloride concentrations in the southern part of 

this area. Chloride concentrations in well clusters EB-21 and 

EB-13 (E-E’, fig. 15B) remained less than the Federal SDWR 

for chloride of 250 mg/L since the mid-1970s (beginning of 

data collection), which indicates that the Burrton oil-field 

brines have had minimal effect on chloride in groundwater in 

these areas. Well clusters EB-10, EB-9, EB-8, and EB-12 had 

chloride concentrations exceeding the Federal SDWR for at 

least part of the period in at least one well in each cluster. The 

largest chloride concentrations did not occur in the deepest 

well in each of these clusters, which indicates that less permeable discontinuous clay layers were restricting the migration 

of the denser saline water into the deepest part of the aquifer. 

Chloride concentrations in well EB-10B have decreased since 

the 1980s, whereas concentrations in wells EB-9B and EB-8B 

have increased. The abrupt increase in chloride concentrations 

in water from shallow well EB-10A in about 1990 probably 

is the arrival of Burrton oil-field brines in the shallow aquifer. 

Chloride concentrations in well EB-12B temporarily exceeded 

the Federal SDWR in the late 1990s and early 2000s. Chloride concentrations in the shallow and deep wells in clusters 

IW-04, IW-08, and IW-13 were similar to those in wells of 

similar depths in clusters EB-9, EB-8, and EB-12. Therefore, 

the chloride concentrations in water from the EB wells during 

the late 1970s to 2001 were used as estimates of chloride concentrations at the IW wells during this period.

Well clusters IW-02 (F-F’, fig.15B), P-32 (D-D’, fig. 

15B), and P-35 (C-C’, fig. 15B) had chloride concentrations 

of less than the Federal SDWR, indicating no advance of 

the Burrton oil-field brines into these areas. In well clusters 

EB-16 (F-F’, fig.15B), EB-20 (H-H’, fig.15B), and EB-14 

(I-I’ fig.15B), the chloride concentrations in the deep wells 

increased since about 1980, whereas water in the shallow 

wells had smaller increases. In well clusters EB-16 and EB-15, 

chloride concentrations in the deep wells now (2005) exceed 

those in the shallow wells and the Federal SDWR. Differing 

trends in chloride concentrations during the 1990s in wells 

EB-16B and EB-16C, which are both in the deep parts of the 

aquifer, indicate that hydraulic conditions are not homogenous 

in the deep parts of the aquifer. Shallow wells EB-16A and 

IW-05A and deep wells EB-16C and IW-05C are near each 

other and have similar chloride concentrations; therefore, 

chloride concentrations in water from the EB-16 wells were 

used as estimates of the chloride concentrations in water 

from the IW-05 wells during the 1980s through early 2000s. 

Chloride concentrations in the shallow and deep wells at well 

clusters EB-14 and EB-19 and concentrations in water from 

well clusters IW-09 and IW-14 indicate that it may have been 

problematic to do a similar backward-in-time extension of 

the chloride concentrations for the deep and shallow wells at 

clusters IW-09 and IW-14 because they were about 1 mi apart 

and were near the front of the brine movement from Burrton 

toward the south and east. 

During the past 40 to 45 years (since about 1960), 

increased chloride concentrations originating from brine 

disposal related to past oil and gas activities near Burrton 

(assumed to be centered at well cluster P-31) have migrated 

about 3 mi downgradient toward the southeast in both shallow and deep groundwater. Historical downward migration/

transport has progressed from an area centered near Burrton 

and from the shallow to deep parts of the aquifer. The downward migration of the chloride is controlled by the hydraulic 

gradient in the aquifer, dispersion of chloride, and discontinuous clay layers that can limit downward migration for short 

lateral distances. The rate of change in chloride concentrations in the upper 100 to 150 ft of the aquifer from Burrton 

(well cluster P-31) to well cluster P-29 was about 40 (mg/L)/

yr as the plume reached the well cluster location (mid-1950s). 

Since about 1970, the increased concentrations in well cluster 

P30 continued to be about 15 (mg/L)/yr, but at well P-29A 

there was little change during the past 10 years. The chloride 

concentration increase since about 1979 from well cluster 

EB-8 to well cluster EB-14 also was about 20 to 50 (mg/L)/yr. 

Increased chloride concentrations progressed about 1 mi in 15 

years from a baseline concentration in the aquifer of about 50 

to 250 mg/L. The 2005 rates of increase near Phase 1 recharge 

locations RRW-3, RRW4, and RB-1 and at well cluster EB-15 

(fig. 15) were about 40 (mg/L)/yr compared to about 8 (mg/L)/

yr at downgradient well cluster EB-20. At well EB-15B, 

chloride concentrations increased from 15 mg/L in 1979 to 

more than 250 mg/L in 1986. Chloride concentrations in well 

EB-15C in 2005 were about 1,000 mg/L. In downgradient well 

cluster EB-20, chloride concentrations increased from about 

30 to 150 mg/L in 15 years. 

Increased chloride concentrations in the shallow parts of 

the aquifer migrated less than 0.5 mi during the past decade. 

The 2005 slower rate of movement probably is caused by the 
40 Water Quality in the Equus Beds Aquifer and the Little Arkansas River, South-Central Kansas 

decrease in the hydraulic gradient, which slows the movement 

of the chloride plume. However, the aquifer heterogeneity and 

clay-rich layers at monitoring depths for the index wells near 

well IW-09A (53-ft depth) may miss the primary movement 

of chloride at about 100 to 120 ft below ground surface (well 

EB-14B). The rates of chloride movement and concentration increase in that area were about 1 mi in 15 years and 40 

(mg/L)/yr, respectively. On the basis of these results, artificial 

recharge near Phase-I recharge locations RRW-3, RRW-4, and 

RB-1(fig. 15A) (especially at depths of 100 to 150 ft) could 

create a barrier to saltwater migration.

Data also indicate that chloride concentrations in deep 

parts of the aquifer in the southern part of the study area 

decreased and appeared to migrate toward the Arkansas River. 

Migration of chloride along the Arkansas River is controlled 

by the hydraulic gradient in the aquifer, which also decreased 

from 1992 through 2006, and the chloride concentrations in 

the Arkansas River (typically about 500 to 600 mg/L) (Myers 

and others, 1996; Kansas Department of Health and Environment, 2006b).

With increasing chloride concentration, the specific conductance value of water (ability of water to conduct electricity) also will increase (Hem, 1992). Regression analysis of the 

statistical relation between sampled specific conductance and 

chloride concentrations is shown for shallow index wells (fig. 

16A), deep index wells (fig. 16B), and the average of shallow 

and deep wells at each index well site (fig. 16C). The regression models and their respective coefficients of determination 

(R2

) and root mean square error (RMSE) for figures 16A, B, 

and C follow:

Shallow index wells: 

chloride = 0.164 specific conductance – 73.17; 

R2 = 0.550; RMSE = 71.9;

Deep index wells: 

chloride = 0.298 specific conductance – 171; 

R2 = 0.888; RMSE =80.6;

Combined shallow and deep index wells: 

chloride = 0.260 specific conductance – 148; 

R2

 = 0.783; RMSE = 86.8;

where chloride is in milligrams per liter and specific conductance is in microsiemens per centimeter at 25 degrees Celsius. 

The coefficients of determination for these regressions indicate 

that specific conductance explains at least 55 percent of the 

variability in chloride concentrations, which indicates that it is 

an acceptable predictor of chloride in groundwater.

Nutrients

Nutrients such as nitrogen and phosphorus are closely 

related to agricultural activities because of their presence in 

fertilizers and animal waste. Nutrient-rich water from farms 

and feedlots can run off into streams or percolate into groundwater. Other sources of nutrients in water include wastewater 

treatment plants, sewage lagoons, and domestic septic tanks 

(Ziegler and others, 1999; 2001). 

Nitrite plus nitrate (hereafter referred to as nitrate) in 

drinking water can cause adverse effects in humans. The 

Federal MCL for nitrate is 10 mg/L as nitrogen, which is the 

concentration above which methemoglobinemia, or blue baby 

syndrome, may occur in infants (U.S. Environmental Protection Agency, 2005). Nitrate concentrations from samples 

analyzed for this study are summarized in table A-4. 

All nitrate concentrations in water samples collected at 

the two surface-water monitoring sites on the Little Arkansas 

River from 1995 through 2005 were less than the MCL for 

nitrate (table 1). The median nitrate concentration in water 

samples collected during this period from the Little Arkansas River near Halstead and near Sedgwick was 0.85 mg/L. 

Nitrate concentration in samples collected from 1995 through 

2005 from the two sites on the Little Arkansas River ranged 

from less than 0.02 to 9.4 mg/L (table 1). The maximum 

nitrate concentration of 9.4 mg/L occurred near Sedgwick 

(table A-4). All nitrate concentrations were less than the 

MCL in the samples of treated source water at the Sedgwick 

recharge site (table A-4). No regression models currently 

(2009) exist to compute nitrate concentration in the Little 

Arkansas River from continuously measured data at the monitoring sites near Halstead and near Sedgwick.

Average nitrate concentrations exceeded the MCL in 

water samples from about 13 percent of the shallow index 

wells (table 2). Nitrate concentrations exceeded the MCL at 

least once in the shallow parts of the aquifer in the northern 

part of the study area between Burrton and the Little Arkansas River (wells SMW-H4, IW-06A, and IW-09A; fig. 6, 

table A-4) and in the southern part of the study area between 

Sedgwick and the Arkansas River (wells SMW-S11 and 

SMW-S13, IW-30A, 31A, 33A, 36A, and 37A; fig. 6, table 

A-4). The distribution of average nitrate concentrations in the 

shallow parts of the aquifer is shown in figure 17A. This figure 

shows that average nitrate concentrations exceeded the MCL 

in about 9 percent of the shallow aquifer in the study area. In 

the shallow parts of the aquifer, nitrate from sewage lagoons, 

feedlots, and fertilizer runoff is more likely to increase concentrations. Larger nitrate concentrations in the shallow and 

deep groundwater likely were at least partly the result of more 

rapid percolation from agricultural land uses in areas of larger 

effective porosity (fig. 8) and geochemical controls, especially 

in deep groundwater. 

All measured nitrate concentrations in water from wells 

in the deep parts of the aquifer were less than the MCL of 10 

mg/L (tables 2 and A-4). In the deep parts of the aquifer, average nitrate concentrations of less than 1.0 mg/L occurred in 
Water Quality in the Equus Beds Aquifer and Little Arkansas River, 1995–2005 41

Cl = 0.260SC - 148

R2 = 0.783

RMSE = 86.8

Cl = 0.298SC - 171

R2 = 0.888

RMSE = 80.6

Cl = 0.164 SC - 73.17

R2 = 0.550

RMSE = 71.9

Shallow index well

Deep index well

Deep index well

Shallow index well

0

200

400

600

800

1,000

1,200

1,400

0 500 1,000 1,500 2,000 2,500 3,000 3,500 4,000 4,500 5,000

0

200

400

600

800

1,000

1,200

1,400

0

200

400

600

800

1,000

1,200

1,400

C. Combined shallow and deep index wells

B. Deep index wells

A. Shallow index wells

CHLORIDE (Cl) CONCENTRATION, IN MILLIGRAMS PER LITER

SPECIFIC CONDUCTANCE (SC), IN MICROSIEMENS PER CENTIMETER AT 25 DEGREES CELSIUS

R2 = coefficient of determination

RMSE = root mean square error

Figure 16. Statistical relation between specific conductance and chloride concentrations in (A) shallow index wells, (B) deep index 

wells, and (C) combined shallow and deep index wells.
42 Water Quality in the Equus Beds Aquifer and the Little Arkansas River, South-Central Kansas 

Wichita

Newton

Maize

Sedgwick

Colwich

Mount Hope

Andale

Hesston

A. Shallow wells

0 1 2 3 4 5 MILES

0 1 2 3 4 5 KILOMETERS

Base from U.S. Geological Survey digital data, 1:100,000, 1983

Universal Transverse Mercator projection,

Zone 14

Horizontal coordinate information is referenced to the North American

 Datum of 1983 (NAD 83)

97°40'

38°

38°50’

38°05’

55’

35' 30' 97°25'

Little Arkansas River

West Em

ma Creek

Middle Emma Creek

East Emma Creek

Em

ma Creek

Sand Creek

Jester Creek

Valley

Center

Little Arkansas River

Kisiwa Creek

Big Slough

Cowskin Creek

R. 3 W. R. 2 W. R. 1 W.

T.

26

S.

T.

25

S.

T.

24

S.

T.

23

S.

T.

22

S.

R. 4 W.

RENO COUNTY SEDGWICK COUNTY

HARVEY COUNTY

Bentley

IW-38A 0.04 IW-37A

14.1 IW-36A

14.7 IW-35A

1.1

IW-34A 0.02

IW-33A

18.5

IW-32A 2.32

IW-31A

12.1 IW-30A

11.1

IW-29A 0.03

IW-28A 0.76

IW-26A

3.87 IW-25A

1.9 IW-24A

7.73

IW-23A

<0.02 IW-22A 0.02 IW-21A

<0.02

IW-27A 1.91

IW-20A

0.02 IW-19A

<0.02

IW-18A

0.05

IW-16A

<0.02

IW-17A 0.02 IW-15A

<0.02

IW-14A

<0.02

IW-10A

5.92 IW-09A

7.36

IW-08A

4.26

IW-13A

<0.02

IW-07A

0.03

IW-06A

21.2 IW-05A

4.07

IW-03A 0.02 IW-02A 0.88

IW-01A

1.06

IW-11A-2 0.08

Black

Kettle Creek

Halstead

07144100

07143672

EXPLANATION

ARKANSAS RIVER

7.28

<0.02

0.02

<0.02

<0.02

<0.02

5.42

5.35

4.94

1.58

<0.02

0.21 0.01 0.01

0.03

<0.02; <0.02; <0.02

<0.02

0.02

Burrton

Boundary of study area

Boundary of study area

IW-04A

0.41

IW-12A 0.23

0.06 0.65

Average nitrite plus nitrate concentrations, in milligrams

 per liter

 Less than 1

 1 to less than 10

 Equal to or greater than 10

U.S. Geological Survey streamflow-gaging station,

 continuous real-time water-quality monitoring site and

 site identifier

Data-collection sites

 Index well and site number (2001–05 data)—Lower number

 is average nitrite plus nitrate concentration, in milligrams

 per liter

 Recharge demonstration site (1995–2005 data)—Number is

 average nitrite plus nitrate concentration, in milligrams per liter

 Background well (1995–2005 data)—Number is average nitrite

 plus nitrate concentration, in milligrams per liter

 Indicates less than

IW-38A

<0.02

07144100

4.94

<0.02

<

Note: U.S. Environmental Protection Agency (2006a) Maximum Contaminant

 Level for nitrite plus nitrate is 10 milligrams per liter

Figure 17. Average nitrite plus nitrate concentrations in the study area, 1995–2005, in (A) shallow wells and (B) deep wells.
Water Quality in the Equus Beds Aquifer and Little Arkansas River, 1995–2005 43

Wichita

Newton

Maize

Sedgwick

Colwich

Mount Hope

Andale

Hesston

0.05 

0.02

<0.02

0.05

0.38

<0.02 0.05

0.02

<0.02 

0.02

0.03

<0.02

<0.02

0 1 2 3 4 5 MILES

0 1 2 3 4 5 KILOMETERS

Base from U.S. Geological Survey digital data, 1:100,000, 1983

Universal Transverse Mercator projection,

Zone 14

Horizontal coordinate information is referenced to the North American

 Datum of 1983 (NAD 83)

97°40'

38°

38°50’

38°05’

55’

35' 30' 97°25'

Little Arkansas River

West Em

ma Creek

Middle Emma Creek

East Emma Creek

Em

ma Creek

Sand Creek

Jester Creek

Valley

Center

Little Arkansas River

Kisiwa Creek

Big Slough

Cowskin Creek

R. 3 W. R. 2 W. R. 1 W.

T.

26

S.

T.

25

S.

T.

24

S.

T.

23

S.

T.

22

S.

R. 4 W.

RENO COUNTY SEDGWICK COUNTY

HARVEY COUNTY

Bentley

IW-38C 0.05 IW-37C

4.37 IW-36C

6.81 IW-35C 0.06

IW-34C 0.27

IW-33C

0.46

IW-32C

2.14 

IW-31C 0.13 IW-30C 0.13

IW-29C

0.03

IW-26C

0.03 IW-25C

0.06

IW-24C

0.17

IW-23C

<0.02 IW-22C

<0.02

IW-21C

<0.02

IW-27C

0.12

IW-20C 0.03 IW-19C

<0.02

IW-18C

<0.02

IW-16C

<0.02

IW-17C

<0.02 IW-15C

<0.02

IW-14C 0.02

IW-10C

0.11

IW-09C

0.18 IW-08C

0.4

IW-13C

<0.02

IW-07C

<0.02

IW-06C

0.47 IW-05C 0.15

IW-03C

<0.02

IW-02C 0.03

IW-01C

0.31

IW-11C

<0.02

IW-12C0.1

Black

Kettle Creek

Halstead

07144100

07143672

EXPLANATION

ARKANSAS RIVER

0.16

0.05

3.53

0.14

0.02 0.02

Burrton

Boundary of study area

Boundary of study area

IW-04C 0.27

IW-28C

0.06

B. Deep wells

Average nitrite plus nitrate concentrations, in milligrams

 per liter

 Less than 1

 Equal to or greater than 1

Approximate location of bedrock low (McPherson channel)

U.S. Geological Survey streamflow-gaging station, continuous

 real-time water-quality monitoring site and site identifier

Data-collection sites

 Index well and site number (2001–05 data)—Lower number is average

 nitrite plus nitrate concentration, in milligrams per liter

 Recharge demonstration site (1995–2005 data)—Number is average

 nitrite plus nitrate concentration, in milligrams per liter

 Artificial storage and recovery prototype well (2002–05 data)—Number

 is average nitrite plus nitrate concentration, in milligrams per liter

 Indicates less than

IW-38C 0.05

07144100

3.35

Note: Environmental Protection Agency (2006) Maximum Contaminant

 Level for nitrite plus nitrate is 10 milligrams per liter

<

Figure 17. Average nitrite plus nitrate concentrations in the study area, 1995–2005, in (A) shallow wells and (B) deep wells.—Continued
44 Water Quality in the Equus Beds Aquifer and the Little Arkansas River, South-Central Kansas 

the study area during 1995–2005 were similar. In the shallow parts of the aquifer, the larger dissolved concentrations 

of these trace elements correspond to the areas that have 

been dewatered. Minerals in the aquifer material are oxidized 

resulting in the formation of oxyhdroxides. When water levels 

increase, these oxyhydroxides subsequently are reduced and 

arsenic, iron and manganese that formed after dewatering of 

the shallow parts of the aquifer go into solution and increase 

concentrations in the water if the water remains reduced. In 

the deep parts of the aquifer, reducing conditions are more 

conducive to larger dissolved concentrations of arsenic, iron, 

and manganese. 

Arsenic

Although arsenic is considered to be naturally occurring 

in clay layers associated with iron sulfide minerals (Hem, 

1992), it may be a health concern in drinking water because 

it can cause skin damage, affect the circulatory system, and 

increase cancer risk (U.S. Environmental Protection Agency, 

2005). In 2001, the USEPA proposed lowering the Federal 

MCL for arsenic from 50 to10 micrograms per liter (μg/L), 

and the new lower MCL took effect January 2006 (U.S. 

Environmental Protection Agency, 2001b). The revised arsenic 

Federal MCL of 10 μg/L caused water providers across the 

United States to more closely evaluate their source water for 

arsenic or to increase treatment to meet the criterion. 

Water samples collected from the Little Arkansas River 

near Halstead and near Sedgwick from 1995 through 2005 had 

a median dissolved arsenic concentration of 5 μg/L, which is 

one-half the MCL for arsenic of 10 μg/L (table 1). Dissolved 

arsenic concentrations ranged from 1 to 14 μg/L. Dissolved 

arsenic concentrations exceeded the MCL in about 8 percent 

of the samples collected from 1995 through 2005 from the 

Little Arkansas River (table 1, table A-5). All dissolved arsenic 

concentrations were less than the MCL in the samples of 

treated source water at the Sedgwick recharge site (table A-5).

A regression model was developed to compute dissolved 

arsenic concentrations in the Little Arkansas River on the 

basis of streamflow (Christensen and others, 2003). Computed 

dissolved arsenic concentrations as large as 18 μg/L occurred 

at both surface-water monitoring sites on the Little Arkansas River from 1999 through 2005. Larger dissolved arsenic 

concentrations in stream water generally occurred during low 

streamflow when base flow to the stream was supplied from 

groundwater. Duration curves for computed dissolved arsenic 

are shown in figure 18. In the Little Arkansas River near Halstead, computed dissolved arsenic concentrations exceeded the 

MCL of 10 μg/L about 14 percent of the time and at the Little 

Arkansas River near Sedgwick about 10 percent of the time. 

Computed dissolved arsenic concentrations are available on 

the World Wide Web at http://nrtwq.usgs.gov/ks/. 

Dissolved arsenic concentrations exceeded 10 μg/L in 

water samples from about 10 percent of the index wells completed in the shallow parts of the Equus Beds aquifer (table 

2). Some background wells and some shallow monitoring 

about 90 percent of the study area (fig. 17B). Average nitrate 

concentrations between 1.0 and 10 mg/L were measured in 

wells in the southern part of study area southeast of Bentley. 

Here larger concentrations of nitrate are associated with larger 

effective porosity (fig. 8). In general, nitrate concentrations 

were smaller in deeper parts of the aquifer because of more 

reducing conditions where nitrate is reduced to nitrogen gas 

through denitrification (see reducing conditions shown in 

fig 10). 

The larger nitrate concentrations in water from shallow wells were consistent with a study of larger areal extent 

done by Spruill (1982) that reported about 20 percent of 

water samples from wells less than 100 ft deep in Quaternary 

fluvial (stream-borne) and eolian (windblown) deposits in 

central Kansas (including the Equus Beds aquifer) had nitrate 

concentrations exceeding 10 mg/L. None of the water samples 

from wells more than 100 ft deep in these same deposits had 

nitrate concentrations exceeding 10 mg/L. Townsend and 

Young (2000) also reported that water samples from shallower 

wells were more likely to have larger nitrate concentrations 

than those from deeper wells. Townsend and Young (2000) 

further indicated that groundwater in Kansas with nitrate 

concentrations greater than 3.0 mg/L have been affected by 

anthropogenic (human-related) activities. Pope and others 

(2001, 2002) reported nitrate concentrations as large as 18 

mg/L in water from shallow wells in the central High Plains 

aquifer (which includes the Equus Beds aquifer, fig. 1). In 

these previous studies, nitrate concentrations in individual 

water samples from wells nearest to the Equus Beds study 

area were 0.56 mg/L (northeast of the Little Arkansas River in 

McPherson County) and 7.5 mg/L (southwest of the Arkansas 

River in Reno County) (Pope and others, 2001), and 0.82 and 

5.6 mg/L (south of the study area in Sedgwick County) (Pope 

and others, 2002). These concentrations were within the range 

of nitrate concentrations detected in this study, which indicates 

that nitrate concentrations measured in the Equus Beds aquifer 

were similar to concentrations of nitrate detected in the rest of 

the central High Plains aquifer. 

Trace Elements

Dissolved concentrations of trace elements discussed in 

this report include arsenic, iron, and manganese. Dissolved 

concentrations are defined operationally by filtering the 

water samples through a 0.45-μm pore-size filter. Arsenic is a 

potential carcinogen, and iron and manganese precipitates can 

plug wells and give water a bad taste and color. Summaries of 

dissolved trace element analyses for this study are shown in 

table A-5. The infiltration of stream water or treated water into 

the Equus Beds aquifer by artificial recharge operations could 

affect the mobility of dissolved arsenic or could stimulate the 

growth of bacteria and cause precipitation of iron and manganese minerals from groundwater.

The areal distributions of larger dissolved arsenic, iron, 

and manganese concentrations in the Equus Beds aquifer in 
Water Quality in the Equus Beds Aquifer and Little Arkansas River, 1995–2005 45

1

10

100

0 20 40 60 80 100

07143672 Little Arkansas River at Highway 50 near Halstead, Kansas

07144100 Little Arkansas River near Sedgwick, Kansas

PERCENTAGE OF TIME INDICATED VALUE WAS EQUALLED OR EXCEEDED

U.S. Environmental Protection Agency (2006a) Maximum Contaminant Level (10 micrograms per liter)

COMPUTED DISSOLVED ARSENIC CONCENTRATION, IN MICROGRAMS PER LITER AS ARSENIC

Figure. 18 Duration curves of computed dissolved arsenic concentrations, 1995–2005; Little Arkansas River near Halstead and near 

Sedgwick, Kansas.

wells at the diversion well site near Halstead had average dissolved arsenic concentrations exceeding the MCL of 10 μg/L 

before and after artificial recharge during 1997 through 2002 

(table A-5). Some index wells with average dissolved arsenic 

concentrations less than the MCL had at least one sample 

with arsenic detected at a concentration greater than the MCL 

(table A-5). In the shallow parts of the aquifer, the largest 

average dissolved arsenic concentration was 26 μg/L at well 

EB-145-A5 near Halstead (fig. 6; table A-5), and the largest 

arsenic concentration in a single sample was 55 μg/L at well 

IW-04A (table A-5). Arsenic concentrations in water samples 

from the shallow parts of the aquifer generally were larger 

near the Little Arkansas River and near Burrton (fig. 19A). 

Average dissolved arsenic concentrations exceeded the MCL 

near Burrton, northwest of Sedgwick, and in an area extending diagonally to the southwest from near Halstead (fig. 19A). 

Average dissolved concentrations of arsenic in the shallow 

parts of the aquifer exceeded the MCL in 6 percent of the 

study area from 1995 through 2005 (fig. 19A).

Thirty-four percent of water samples from the deep index 

wells had dissolved arsenic concentrations that exceeded 

the MCL (table 2). Average dissolved arsenic concentrations exceeding the MCL also occurred in some of the ASR 

prototype wells and deep wells associated with the Halstead 

diversion and recharge sites (table A-5). Some deep wells with 

average dissolved arsenic concentrations less than the MCL 

had at least one sample with arsenic concentrations detected 

that exceeded the MCL (table A-5). The largest average (29.1 

μg/L) and single-sample (48.9 μg/L) dissolved arsenic concentrations occurred in the deep parts of the aquifer in samples 

from well EB-145-P-D5 near Halstead (table A-5). Larger concentrations of arsenic in the deep parts of the aquifer occurred 

on the west side of the study area near Kisiwa Creek and on 

the eastern side of the study area along the Little Arkansas 

River (fig. 19B). Arsenic concentrations were smallest in the 

southern part of the study area along the Arkansas River. Average dissolved concentrations of arsenic in the deep parts of the 

aquifer exceeded the MCL in 35 percent of the study area from 

1995 through 2005 (fig. 19B).

The mobility of arsenic in the hydrologic environment 

generally is controlled by two categories of processes—

adsorption and desorption reactions and solid-phase precipitation and dissolution reactions (Hem, 1992; Hinkle and Polette, 

1999; Smedley and Kinniburgh, 2002; McMahon and Chapelle, 2008). These processes are affected by pH, oxidation/

reduction reactions, and the presence of competing anions in 

the water, all of which could be altered as a result of artificial 

recharge activities. The adsorption of arsenic to iron-oxide 
46 Water Quality in the Equus Beds Aquifer and the Little Arkansas River, South-Central Kansas 

Wichita

Newton

Maize

Sedgwick

Colwich

Mount Hope

Andale

Hesston

A. Shallow wells

0 1 2 3 4 5 MILES

0 1 2 3 4 5 KILOMETERS

Base from U.S. Geological Survey digital data, 1:100,000, 1983

Universal Transverse Mercator projection,

Zone 14

Horizontal coordinate information is referenced to the North American

 Datum of 1983 (NAD 83)

97°40'

38°

38°50’

38°05’

55’

35' 30' 97°25'

Little Arkansas River

West Em

ma Creek

Middle Emma Creek

East Emma Creek

Em

ma Creek

Sand Creek

Jester Creek

Valley

Center

Little Arkansas River

Kisiwa Creek

Big Slough

Cowskin Creek

R. 3 W. R. 2 W. R. 1 W.

T.

26

S.

T.

25

S.

T.

24

S.

T.

23

S.

T.

22

S.

R. 4 W.

RENO COUNTY SEDGWICK COUNTY

HARVEY COUNTY

Bentley

IW-38A4.0 IW-37A

<1 IW-36A

<1 IW-35A

<1

IW-34A4.7

IW-33A

<1

IW-32A<1

IW-31A

<1 IW-30A

<1

IW-29A

9.7

IW-28A<1

IW-26A

IW-25A <1

<1 IW-24A

<1

IW-23A7.6 IW-22A<1 IW-21A

2.7

IW-27A<1

IW-20A

4.0 IW-19A4.3

IW-18A

<1

IW-16A

4.8

IW-17A9.6 IW-15A

14.8

IW-14A4.4

IW-10A

<1

IW-09A

<1

IW-08A

<1

IW-13A

6.7

IW-07A

11.5

IW-06A

<1 IW-05A

<1

IW-02A<1

IW-01A

<1

IW-11A-2 11.9

Black

Kettle Creek

Halstead

07144100

07143672

EXPLANATION

Average arsenic concentrations, in micrograms per liter

 Less than 5

 5 to less than 10

 10 to less than 15

U.S. Geological Survey streamflow-gaging station,

 continuous real-time water-quality monitoring site

 and site identifier

Data-collection sites

 Index well and site identifier (2001–05 data)—Lower number

 is average arsenic concentration, in micrograms per liter

 Recharge demonstration site (1995–2005 data)—Number is

 average arsenic concentration, in micrograms per liter

 Background well (1995–2005 data)—Number is average

 arsenic concentration, in micrograms per liter

 Indicates less than

IW-15A 14.8

07144100

<1

10

ARKANSAS RIVER

2.8

2.6

9.2

7.5

10

4.4

<1

1.8

<1

2.2

25.6

1.6 11.5 11.9

3.9 5.6

17.2 1.3; 1.3; <1

<1

0.7

Burrton

Boundary of study area

Boundary of study area

IW-04A

17.1

15 to less than 20

Equal to or greater than 20 

IW-12A8.1

Note: U.S. Environmental Protection Agency (2006a) Maximum

 Contaminant Level for arsenic is 10 micrograms per liter

IW-03A3.1

<

Figure 19. Average arsenic concentrations in the study area, 1995–2005, in (A) shallow wells and (B) deep wells.
Water Quality in the Equus Beds Aquifer and Little Arkansas River, 1995–2005 47

Wichita

Newton

Maize

Sedgwick

Colwich

Mount Hope

Andale

6.3

2.8

4.7

6.3

2.2

 7.4 10.6 

10

6.4

7.7

4.2 

13.7 12.3

0 1 2 3 4 5 MILES

0 1 2 3 4 5 KILOMETERS

Base from U.S. Geological Survey digital data, 1:100,000, 1983

Universal Transverse Mercator projection,

Zone 14

Horizontal coordinate information is referenced to the North American

 Datum of 1983 (NAD 83)

97°40'

38°

38°50’

38°05’

55’

35' 30' 97°25'

West Em

ma Creek

Middle Emma Creek

East Emma Creek

Em

ma Creek

Sand Creek

Jester Creek

Valley

Center

Little Arkansas River

Kisiwa Creek

Big Slough

Cowskin Creek

R. 3 W. R. 2 W. R. 1 W.

T.

26

S.

T.

25

S.

T.

24

S.

T.

23

S.

T.

22

S.

R. 4 W.

RENO COUNTY SEDGWICK COUNTY

HARVEY COUNTY

Bentley

IW-38C

<1 IW-37C

<1

IW-36C

1.0

IW-35C

1.8

IW-34C

3.8

IW-33C

2.3

IW-32C

<1

IW-31C

1.4 IW-30C

<1

IW-29C

13.3

IW-26C

2.5 IW-25C

<1

IW-24C

<1

IW-23C

15.2 IW-22C

15.8

IW-21C

7.5

IW-27C

1.3

IW-20C

13

IW-19C

2.3

IW-18C

2.1

IW-16C

6.1

IW-17C

21.6

IW-15C

7.3

IW-14C

16.7

IW-10C

8.7

IW-09C

17.3

IW-08C

11.2

IW-13C

18.3

IW-07C

12.4

IW-06C

5.8 IW-05C

5.5

IW-02C

1.4

IW-01C

13.6

IW-11C

12.1

IW-12C

16.9

Black

Kettle Creek

Halstead

07144100

07143672

ARKANSAS RIVER

2.9

17.3

4.1

9.9

29.1

20.1

Burrton

Boundary of study area

Boundary of study area

IW-04C

7.5

IW-28C

2.2

EXPLANATION

Average arsenic concentrations, in micrograms per liter

 Less than 5

 5 to less than 10

 10 to less than 15

Approximate location of bedrock low

(McPherson channel)

U.S. Geological Survey streamflow-gaging station,

 continuous real-time water-quality monitoring site

 and site identifier

Data-collection sites

 Index well and site identifier (2001–05 data)—Lower number

 is average arsenic concentration, in micrograms per liter

 Recharge demonstration site (1995–2005 data)—Number is

 average arsenic concentration, in micrograms per liter

 Artificial storage and recovery prototype well (2002–05 data)—

 Number is average arsenic concentration, in micrograms per liter

 Indicates less than

IW-15C

7.3

07144100

4.1

15 to less than 20

Equal to or greater

than 20 

Little Arkansas River

IW-03C

9.3

Note: U.S. Environmental Protection Agency (2006a) Maximum

 Contaminant Level for arsenic is 10 micrograms per liter

B. Deep wells

<

Figure 19. Average arsenic concentrations in the study area, 1995–2005, in (A) shallow wells and (B) deep wells.—Continued
48 Water Quality in the Equus Beds Aquifer and the Little Arkansas River, South-Central Kansas 

surfaces tends to decrease as pH increases; therefore, changes 

in pH of the groundwater can promote adsorption or desorption of arsenic. The oxidation state in which arsenic occurs has 

an important effect on the mobility of arsenic. Arsenate (As5+; 

H2AsO4

-

) is dominant under oxidizing conditions and pH values between 3 and 7, and arsenite (As3+; HAsO2

) is dominant 

under more reducing conditions.

Dissolved arsenate and arsenite concentrations detected 

in the Equus Beds aquifer from 1995 through 2005 are 

presented in table A-5. Adsorption or coprecipitation by iron 

oxyhydroxide and release from sulfide mineral dissolution in 

chemically reduced clay appear to be primary factors that can 

maintain arsenic at small concentrations in water (Hem, 1992). 

Effects of artificial recharge on concentrations of arsenic in 

the aquifer potentially can be minimized by maintaining the 

oxidation-reduction potentials as near 1995–2005 baseline 

conditions as possible (Schmidt and others, 2007). However, 

in many areas of the aquifer, especially the deeper parts, the 

geochemical conditions are conducive to large dissolved 

arsenic concentrations, and it may be possible to use artificial 

recharge to create a less reducing geochemical environment, 

which decreases some of the arsenic and iron dissolved in 

the water thereby improving the overall water quality in the 

aquifer.

Dissolved arsenic concentrations generally were larger 

in deep parts of the aquifer than in shallow parts. The differences in arsenic concentration in water samples from 

shallow and deep index wells were because of the different 

geologic composition of the aquifer zones and differences in 

the reduction-oxidation potentials in the aquifer. Dissolved 

arsenic concentrations were larger than 10 μg/L in the northern two-thirds of the study area (mostly in Harvey County), 

where effective porosities were smaller (clay layers abundant) 

(fig. 8). In the southern one-third of the study area, the Equus

Beds aquifer consists of mostly sand and gravel. The northern 

two-thirds of the study area also had water-level declines of 

nearly 50 ft through 1992, which subsequently have recovered 

by almost 20 ft in 2005. Dissolved arsenic concentrations also 

were inversely related to ORP. The larger dissolved arsenic 

concentrations in deep wells were most common in areas with 

reducing conditions where the ORP was less than 250 mV. 

Clay is a natural source of arsenic because arsenic can occur 

as an impurity in the mineral pyrite (Hem, 1992; Welch and 

others, 2000), which commonly occurs in clay. These findings 

are corroborated by Gotkowitz and others (2004), who investigated the relation between larger concentrations of arsenic in 

borehole water under no or small pumping rates and reported 

that large concentrations of arsenic were caused by the reducing condition of arsenic-bearing iron (hydroxide) oxides in the 

borehole wall. 

Behavior of stable forms of arsenic (arsenate and arsenite 

oxyanions) in water corresponds to changes in pH and ORP 

(Hem, 1992). Although pH did not have a strong relation to 

concentration of arsenic in groundwater in the Equus Beds 

aquifer, dissolved arsenic concentrations decreased overall as 

ORP increased. Regression plots showing the relation between 

measured ORP and sampled dissolved arsenic concentrations 

are shown for shallow index wells (fig. 20 ), deep index wells 

(fig. 20B), and the average of shallow and deep wells at index 

well sites (fig. 20C). The regression models and their respective coefficients of determination (R2

) and root mean square 

error (RMSE) for figures 20A, B, and C follow:

Shallow index wells: 

arsenic = 32,600 ORP-1.730; 

R2 = 0.619; RMSE = 4.36;

Deep index wells: 

arsenic = 21,400 ORP-1.593; 

R2 = 0.567; RMSE = 5.17; and

Combined shallow and deep index wells: 

arsenic = 41,700 ORP-.1.747; 

R2 = 0.630; RMSE = 5.19;

where arsenic is in micrograms per liter and ORP is in millivolts relative to the standard hydrogen electrode. The coefficients of determination for these regressions indicate that 

ORP was useful estimating dissolved arsenic concentrations 

and that ORP explains about 60 percent of the variability in 

dissolved arsenic concentrations in groundwater. 

Iron

Iron in water is derived from rocks and soils and is 

commonly measured in chemical analyses. Water containing 

excessive concentrations of iron is unpleasant to drink because 

of its odor, metallic taste, and rusty color. The Federal SDWR 

for iron is 300 μg/L (U.S. Environmental Protection Agency, 

2005). At concentrations exceeding the Federal SDWR, iron 

forms red oxyhydroxide precipitates in water that stain laundry 

and plumbing fixtures and causes corrosion. Iron becomes 

more soluble in water at small pH and small ORP values. 

Bacterial activity also may affect the concentration of iron in 

water (Hem, 1992) and can be of particular concern in artificial recharge operations. The addition of oxygenated water to 

a system could create favorable conditions for increased bacterial activity. In turn, increased biological activity can produce 

a biofilm that can clog well screens and decrease the efficiency 

of injection wells (Schmidt and others, 2007).

Water samples collected from the Little Arkansas River 

from 1995 through 2005 had a median dissolved iron concentration of 10 μg/L, which was much less than the Federal 

SDWR of 300 μg/L (table 1). Dissolved iron concentrations 

ranged from less than 5 to 860 μg/L. Samples with dissolved 

iron concentrations that exceeded the Federal SDWR were 

collected from both surface-water monitoring sites on the 

Little Arkansas River (table A-5). Generally, larger concentrations of iron likely were caused by colloids that pass through 

the 0.45-μm filters when sediment concentrations are larger. 
Water Quality in the Equus Beds Aquifer and Little Arkansas River, 1995–2005 49

As = 41,700ORP -1.747

R2 = 0.630

RMSE = 5.19

As = 21,400ORP -1.593

R2 = 0.567

RMSE = 5.17

As = 32,600ORP -1.730

R2 = 0.619

RMSE = 4.36

Shallow index well

Shallow index well

Deep index well

Deep index well

0

10

30

20

40

50

60

70

80

90

100

110

120

0

10

30

20

40

50

60

70

80

90

100

110

120

0

10

30

20

40

50

60

70

80

90

100

110

120

0 100 200 300 400 500 600 700 800

C. Combined shallow and deep index wells

B. Deep index wells

A. Shallow index wells

ARSENIC (As) CONCENTRATION IN SHALLOW AND DEEP INDEX WELLS, IN MICROGRAMS PER LITER

OXIDATION-REDUCTION POTENTIAL (ORP), IN MILLIVOLTS

R2 = coefficient of determination

RMSE = root mean square error

Figure 20. Statistical relation between oxidation-reduction potential and arsenic concentrations in (A) shallow index wells, (B) deep 

index wells, and (C) combined shallow and deep index wells.
50 Water Quality in the Equus Beds Aquifer and the Little Arkansas River, South-Central Kansas 

However, the Federal SDWR was exceeded in less than 2 percent of water samples collected. Dissolved iron concentrations 

were all less than the Federal SDWR in the samples collected 

from the treated source water at the Sedgwick recharge site 

during 1997-2000 (table A-5). No computations of dissolved 

iron concentrations from continuously measured constituents 

in the Little Arkansas River were made.

The average concentration of dissolved iron in groundwater exceeded the Federal SDWR in water samples from 

about 40 and 45 percent of the index wells in the shallow and 

deep parts of the aquifer, respectively (table 2). Single-sample 

dissolved concentrations of iron were as large as 40,700 μg/L 

in the shallow part of the aquifer at well IW-20A and as large 

as 15,800 μg/L in the deep part of the aquifer at well IW-08C 

(table A-5). Areal distributions of average dissolved iron concentrations in shallow and deep wells from 1995 through 2005 

are shown in figure 21. Dissolved concentrations of iron that 

exceeded 300 μg/L in the shallow and deep parts of the aquifer 

occurred mostly in the central part of study area and along the 

Little Arkansas River. About 44 percent of the study area had 

average dissolved iron concentrations that exceeded the Federal SDWR in water from both shallow and deep wells. 

Iron in the Equus Beds aquifer most likely occurs naturally from oxidation of pyrite, which occurs in clay in the 

aquifer. Very large dissolved concentrations of iron (greater 

than 3,000 μg/L) generally corresponded with areas of larger 

water-level declines and subsequent recovery (figs. 21 and 

4). These larger concentrations likely were caused by oxidation of the aquifer material. After an increase in water levels, 

ferric oxyhydroxides that formed during the period of dewatering and oxidation of the aquifer material are reduced and 

are dissolved in the water. These areas also had larger sulfate 

concentrations, which also indicated that oxidation occurred 

during the period of dewatering. Previously published data by 

Hathaway and others (1981) indicated dissolved iron concentrations larger than 1,500 μg/L in groundwater near Burrton 

and Kisiwa Creek, and concentrations less than 50 μg/L 

occurred near the Arkansas River. On the basis of the data collected by Hathaway and others and the study described herein, 

iron concentrations have not changed substantially during the 

past 20 years.

Manganese

Manganese is another trace element that is commonly 

analyzed in water because of its undesirable tendency to 

deposit black oxide stains. Like iron, manganese originates 

from rocks and soil, but it is much less abundant than iron 

(Hem, 1992). The Federal SDWR for manganese is 50 mg/L 

(U.S. Environmental Protection Agency, 2005). At concentrations larger than the Federal SDWR, consumers may notice a 

bitter metallic taste, black to brown water, and black staining 

on plumbing fixtures (U.S. Environmental Protection Agency, 

2005).

Water samples collected from 1995 through 2005 at the 

two surface-water monitoring sites on the Little Arkansas 

River had a median dissolved manganese concentration of 60 

μg/L, which exceeds the Federal SDWR (table 1). Dissolved 

manganese concentrations in water samples collected from the 

Little Arkansas River ranged from less than 1 to 1,140 μg/L. 

Water samples from both sites on the Little Arkansas River 

exceeded the Federal SDWR (table A-5). Dissolved concentrations exceeded the Federal SDWR in 48 percent of the water 

samples collected from the Little Arkansas River (table 1). 

Median dissolved manganese concentrations in samples of the 

treated source water at the Sedgwick recharge site collected 

during the 1997-2000 recharge demonstration period were 

less than 5 μg/L; however, dissolved manganese concentrations in some samples of treated source water at the Sedgwick 

recharge site were as large as 180 μg/L and exceeded the Federal SDWR (table A-5). No concentrations were computed on 

the basis of continuously measured constituents in the Little 

Arkansas River.

Average dissolved manganese concentrations exceeded 

the Federal SDWR in water samples from about 58 percent of 

the index wells in the shallow parts of the Equus Beds aquifer 

in the study area (fig. 22A, table 2). The largest single-sample 

dissolved manganese concentration in the shallow parts of the 

aquifer was 4,320 μg/L in water from well TH-08-A1 (table 

A-5). In shallow groundwater, average dissolved concentrations of manganese exceeded 50 μg/L in 60 percent of the 

study area (fig. 22A). In shallow parts of the aquifer, almost all 

of the study area located in Harvey County had average dissolved manganese concentrations that exceeded 50 μg/L (fig. 

22A). Average dissolved manganese concentrations larger than 

500 μg/L were detected near Burrton, in a large area about 5 

mi southwest of Halstead, and areas near the Little Arkansas 

and Arkansas Rivers. 

Average dissolved manganese concentrations exceeded 

the Federal SDWR in water samples from about 95 percent of 

the index wells in the deep parts of the aquifer (table 2). A dissolved manganese concentration of 1,450 μg/L in water from 

well IW-12C was the largest for a single sample from the deep 

parts of the aquifer (table A-5). About 97 percent of the study 

area had average dissolved manganese concentrations that 

exceeded 50 μg/L in water from deep wells (fig. 22B). Average 

dissolved manganese concentrations exceeded 500 μg/L in 

water from the deep parts of the aquifer in a large area in the 

center of the study area and two smaller areas near Halstead 

(fig. 22B). 

The area with average manganese concentrations that 

exceeded 50 μg/L was larger in the deep parts of the aquifer 

than in the shallow parts of the aquifer probably because of 

the difference in ORP between the two depths. In the shallow parts of the aquifer where more oxidizing conditions 

exist, manganese likely is oxidized to form manganese oxide, 

which is insoluble in water. This precipitate is removed when 

filtering the water samples, which results in smaller dissolved 

manganese concentrations in water collected from shallow 

wells. Figure 22 shows a similar distribution of manganese 

concentrations in the Equus Beds aquifer to that published by 

Hathaway and others (1981). That report and this study had 
Water Quality in the Equus Beds Aquifer and Little Arkansas River, 1995–2005 51

Wichita

Newton

Maize

Sedgwick

Colwich

Mount Hope

Andale

Hesston

0 1 2 3 4 5 MILES

0 1 2 3 4 5 KILOMETERS

Base from U.S. Geological Survey digital data, 1:100,000, 1983

Universal Transverse Mercator projection,

Zone 14

Horizontal coordinate information is referenced to the North American

 Datum of 1983 (NAD 83)

97°40'

38°

38°50’

38°05’

55’

35' 30' 97°25'

Little Arkansas River

West Em

ma Creek

Middle Emma Creek

East Emma Creek

Em

ma Creek

Sand Creek

Jester Creek

Valley

Center

Little Arkansas River

Kisiwa Creek

Big Slough

Cowskin Creek

R. 3 W. R. 2 W. R. 1 W.

T.

26

S.

T.

25

S.

T.

24

S.

T.

23

S.

T.

22

S.

R. 4 W.

RENO COUNTY SEDGWICK COUNTY

HARVEY COUNTY

Bentley

IW-38A695 IW-37A

<5 IW-36A

<5 IW-35A

<5

IW-34A420

IW-33A

5.0

IW-32A<5

IW-31A

<5 IW-30A

5.3

IW-29A

3,830

IW-28A<5

IW-26A

IW-25A <5

<5 IW-24A

<5

IW-23A

1,590 IW-22A151 IW-21A

7,790

IW-27A<5

IW-20A

37,000 IW-19A

2,710

IW-18A

251

IW-16A

8,280

IW-17A

1,590

IW-15A

7,060

IW-14A

4,890

IW-10A

6.9

IW-09A

<5

IW-08A

174

IW-13A

2,130

IW-07A

94.3

IW-06A

<5 IW-05A

100

IW-03A

2,410 IW-02A<5

IW-01A

<5

IW-11A-2 790

Black

Kettle Creek

Halstead

07144100

07143672

EXPLANATION

Average iron concentrations, in micrograms per liter

 Less than 300

 300 to less than 3,000

 3,000 to less than 30,000

 Equal to or greater than 30,000

U.S. Geological Survey streamflow-gaging station, continuous

 real-time water-quality monitoring site and site identifier

Data-collection sites

 Index well and site identifier (2001–05 data)—Lower number

 is average iron concentration, in micrograms per liter

 Recharge demonstration site (1995–2005 data)—Number is

 average iron concentration, in micrograms per liter

 Background well (1995–2005 data)—Number is average iron

 concentration, in micrograms per liter

 Indicates less than

IW-15A

7,060

07144100

73.5

1,060

ARKANSAS RIVER

16

920

453

1,030

1,060

130

73.5

<5

<5

<5

347

25.5 700 617

<5 274

403

791; 2,110; 3,170

453

663

Burrton

Boundary of study area

Boundary of study area

IW-04A

9,830

IW-12A 43.3

Note: Environmental Protection Agency (2006) Secondary Drinking Water

 Regulation for iron is 300 micrograms per liter

A. Shallow wells

<

Figure 21. Average dissolved iron concentrations in the study area, 1995–2005, in (A) shallow wells and (B) deep wells.
52 Water Quality in the Equus Beds Aquifer and the Little Arkansas River, South-Central Kansas 

Wichita

Newton

Maize

Sedgwick

Colwich

Mount Hope

Andale

<5

15.7

162

<5

125

<5 <5

<5

<5

12.9

7.5 

<5 <5

B. Deep wells

0 1 2 3 4 5 MILES

0 1 2 3 4 5 KILOMETERS

Base from U.S. Geological Survey digital data, 1:100,000, 1983

Universal Transverse Mercator projection,

Zone 14

Horizontal coordinate information is referenced to the North American

 Datum of 1983 (NAD 83)

97°40'

38°

38°50’

38°05’

55’

35' 30' 97°25'

West Em

ma Creek

Middle Emma Creek

East Emma Creek

Em

ma Creek

Sand Creek

Jester Creek

Valley

Center

Little Arkansas River

Kisiwa Creek

Big Slough

Cowskin Creek

R. 3 W. R. 2 W. R. 1 W.

T.

26

S.

T.

25

S.

T.

24

S.

T.

23

S.

T.

22

S.

R. 4 W.

RENO COUNTY SEDGWICK COUNTY

HARVEY COUNTY

Bentley

IW-38C7.1

IW-37C

<5 IW-36C

<5 IW-35C<5

IW-34C<5

IW-33C

7.1

IW-32C<5

IW-31C<5 IW-30C<5

IW-29C

1,680

IW-26C

<5 IW-25C

<5 IW-24C

<5

IW-23C 511 IW-22C 899 IW-21C

10,400

IW-27C

<5

IW-20C

1,840

IW-19C 126

IW-18C

501

IW-16C

4,420

IW-17C 850 IW-15C

20

IW-14C

2,090

IW-10C

800

IW-09C

92.9

IW-08C

15,200

IW-13C

2,060

IW-07C

45.7

IW-06C

509 IW-05C 889

IW-03C 40.8 IW-02C 471

IW-01C

97.1

IW-11C 75.7

IW-12C

2,040

Black

Kettle Creek

Halstead

07144100

07143672

ARKANSAS RIVER

<5

195

<5

816

273 414

Burrton

Boundary of study area

Boundary of study area

IW-04C 411

IW-28C

<5

EXPLANATION

Average iron concentrations, in micrograms per liter

 Less than 300

 300 to less than 3,000

 Equal to or greater than 3,000

Approximate location of bedrock low (McPherson channel)

U.S. Geological Survey streamflow-gaging station, continuous

 real-time water-quality monitoring site and site identifier

Data-collection sites

 Index well and site identifier (2001–05 data)—Lower number

 is average iron concentration, in micrograms per liter

 Recharge demonstration site (1995–2005 data)—Number is

 average iron concentration, in micrograms per liter

 Artificial storage and recovery prototype well

 (2002–05 data)—Number is average iron concentration, in

 micrograms per liter

 Indicates less than

IW-15C20

<

07144100

<5

Little Arkansas River

Note: Environmental Protection Agency (2006) Secondary Drinking Water

 Regulation for iron is 300 micrograms per liter

Figure 21. Average dissolved iron concentrations in the study area, 1995–2005, in (A) shallow wells and (B) deep wells.—Continued
Water Quality in the Equus Beds Aquifer and Little Arkansas River, 1995–2005 53

Wichita

Newton

Maize

Sedgwick

Colwich

Mount Hope

Andale

Hesston

0 1 2 3 4 5 MILES

0 1 2 3 4 5 KILOMETERS

Base from U.S. Geological Survey digital data, 1:100,000, 1983

Universal Transverse Mercator projection,

Zone 14

Horizontal coordinate information is referenced to the North American

 Datum of 1983 (NAD 83)

97°40'

38°

38°50’

38°05’

55’

35' 30' 97°25'

Little Arkansas River

West Em

ma Creek

Middle Emma Creek

East Emma Creek

Em

ma Creek

Sand Creek

Jester Creek

Valley

Center

Little Arkansas River

Kisiwa Creek

Big Slough

Cowskin Creek

R. 3 W. R. 2 W. R. 1 W.

T.

26

S.

T.

25

S.

T.

24

S.

T.

23

S.

T.

22

S.

R. 4 W.

RENO COUNTY SEDGWICK COUNTY

HARVEY COUNTY

Bentley

IW-38A554 IW-37A

<5 IW-36A

<5 IW-35A

541

IW-34A 15.7

IW-33A

<5

IW-32A 17.1

IW-31A

<5 IW-30A

<5

IW-29A

828

IW-28A<5

IW-26A

IW-25A <5

<5 IW-24A

<5

IW-23A890 IW-22A 68.2 IW-21A

423

IW-27A<5

IW-20A

967 IW-19A317

IW-18A

18.6

IW-16A

737

IW-17A157 IW-15A

957

IW-14A199

IW-10A

<5

IW-09A

260

IW-08A

85.7

IW-13A

165

IW-07A

353

IW-06A

14.7 IW-05A

220

IW-03A

1,240 IW-02A<5

IW-01A

78.6

IW-11A-2 304

IW-12A125

Black

Kettle Creek

Halstead

07144100

07143672

EXPLANATION

Average manganese concentrations, in micrograms per liter

 Less than 50

 50 to less than 500

 Equal to or greater than 500

U.S. Geological Survey streamflow-gaging station, continuous

 real-time water-quality monitoring site and site identifier

Data-collection sites

 Index well and site identifier (2001–05 data)—Lower number

 is average manganese concentration, in micrograms per liter

 Recharge demonstration site (1995–2005 data)—Number is

 average manganese concentration, in micrograms per liter

 Background well (1995–2005 data)—Number is average

 manganese concentration, in micrograms per liter

IW-15A957

07144100

3

312

ARKANSAS RIVER

12.4

170

562

259

312

520

20.7

2.8

<5

4.6

814

173 900 786

278 934

660

137

96

Burrton

Boundary of study area

Boundary of study area

IW-04A

587 1,040; 1,180; 2,380

Note: U.S. Environmental Protection Agency (2006a) Secondary Drinking-Water

 Regulation for manganese is 50 micrograms per liter

A. Shallow wells

Figure 22. Average dissolved manganese concentrations in the study area, 1995–2005, in (A) shallow wells and (B) deep wells.
54 Water Quality in the Equus Beds Aquifer and the Little Arkansas River, South-Central Kansas 

Wichita

Newton

Maize

Sedgwick

Colwich

Mount Hope

Andale

260

193

302

260

119

278 207

139

199

154

269 

187 164

0 1 2 3 4 5 MILES

0 1 2 3 4 5 KILOMETERS

Base from U.S. Geological Survey digital data, 1:100,000, 1983

Universal Transverse Mercator projection,

Zone 14

Horizontal coordinate information is referenced to the North American

 Datum of 1983 (NAD 83)

97°40'

38°

38°50’

38°05’

55’

35' 30' 97°25'

West Em

ma Creek

Middle Emma Creek

East Emma Creek

Em

ma Creek

Sand Creek

Jester Creek

Valley

Center

Little Arkansas River

Kisiwa Creek

Big Slough

Cowskin Creek

R. 3 W. R. 2 W. R. 1 W.

T.

26

S.

T.

25

S.

T.

24

S.

T.

23

S.

T.

22

S.

R. 4 W.

RENO COUNTY SEDGWICK COUNTY

HARVEY COUNTY

Bentley

IW-38C 306 IW-37C

326 IW-36C

11 IW-35C22

IW-34C 169

IW-33C

157

IW-32C57

IW-31C 300 IW-30C 323

IW-29C

557

IW-26C

225 IW-25C

64 IW-24C

90

IW-23C 497 IW-22C 459 IW-21C

1,070

IW-27C

180

IW-20C

1,210

IW-19C 526

IW-18C

264

IW-16C

883

IW-17C 347 IW-15C

481

IW-14C

1,020

IW-10C

247 IW-09C

416

IW-08C

1,310

IW-13C

503

IW-07C

289

IW-06C

267 IW-05C 669

IW-02C 124

IW-01C

229

IW-11C 221

IW-12C

1,360

Black

Kettle Creek

Halstead

07144100

07143672

ARKANSAS RIVER

232

650

155

510

569 685

Burrton

Boundary of study area

Boundary of study area

IW-04C 534

IW-28C

179

EXPLANATION

Average manganese concentrations, in micrograms per liter

 Less than 50

 50 to less than 500

 Equal to or greater than 500

Approximate location of bedrock low (McPherson channel)

U.S. Geological Survey streamflow-gaging station, continuous

 real-time water-quality monitoring site and site identifier

Data-collection sites

 Index well and site number (2001–05 data)—Lower number

 is average manganese concentration, in micrograms per liter

 Recharge demonstration well (1995–2005 data)—Number is

 average manganese concentration, in micrograms per liter

 Artificial storage and recovery prototype well (2002–05

 data)—Number is average manganese concentration, in

 micrograms per liter

IW-15C 481

07144100

155

Little Arkansas River

 IW-03C 213 

Note: U.S. Environmental Protection Agency (2006a) Secondary Drinking-Water

 Regulation for manganese is 50 micrograms per liter

B. Deep wells

Figure 22. Average dissolved manganese concentrations in the study area, 1995–2005, in (A) shallow wells and (B) deep wells.—

Continued
Water Quality in the Equus Beds Aquifer and Little Arkansas River, 1995–2005 55

shallow aquifer concentrations between 50 and 500 μg/L in 

much of the study area with concentrations exceeding 500 

μg/L near Kisiwa Creek and concentrations less than 50 μg/L 

along the Arkansas River.

Organic Compounds

Many of the organic compounds detected in surface and 

groundwater in the study area are chemicals used in agricultural pesticides and herbicides. These compounds enter 

streams or slowly infiltrate into the aquifer from the application on fields or through irrigation return flow and surface 

runoff. All organic compounds for which at least one analysis 

was performed in surface or groundwater samples collected 

at study sites from 1995 through 2005 are listed in table A-2. 

Those organic compounds that were never detected at any 

sites from 1995 through 2005 also are noted in table A-2. Of 

the more than 300 organic compounds (which included pesticides, herbicides, metabolites, volatile organic compounds, 

acid compounds, base/neutral compounds, and pharmaceutical 

compounds) listed, 88 were detected in at least one sample. 

The criterion for detection was any concentration larger than 

the reporting level for the constituent. Those compounds 

detected in the samples were summarized for groups of datacollection sites in table A-6. 

Alachlor was the only organic compound other than 

atrazine frequently detected (five percent of surface-water 

samples) at levels exceeding USEPA Federal drinking-water 

criterion value (table 1). Alachlor is an herbicide used to control weeds in soybeans. Dissolved concentrations of alachlor 

in the Little Arkansas River near Halstead were as large as 

28 μg/L (table A-6) but rarely exceeded the Federal MCL for 

alachlor of 2.0 μg/L (U.S. Environmental Protection Agency, 

2006a). 

The organic compounds for which the most water 

samples were analyzed were pesticides, especially atrazine 

and triazine herbicides. Ziegler and others (1999) analyzed 

water samples from the Little Arkansas River for dissolved 

triazine herbicides using the enzyme-linked immunosorbent 

assay (ELISA) method and used gas chromatography/mass 

spectrometry (GC/MS) to confirm and quantify the presence 

of atrazine. Using these methods, Ziegler and others (1999) 

reported that atrazine made up 81 percent of triazine compound concentrations analyzed by ELISA for water samples 

collected from the Little Arkansas River. For the purposes of 

this report, dissolved triazine compounds detected by ELISA 

method in surface-water samples are referred to as atrazine. 

In groundwater, the relation between atrazine and triazine 

analysis by ELISA was not as well defined because of the 

small concentrations of atrazine in groundwater that commonly were less than the reporting level for the ELISA method 

of 0.1 μg/L (Ziegler and others, 1999). Therefore, the atrazine 

concentrations in groundwater discussed in this report were 

determined by the GC/MS method (table 2).

Atrazine does not occur naturally in the environment; it is 

an herbicide used on corn and grain sorghum, which are crops 

commonly grown in the study area. Atrazine can cause damage to internal organs in humans (USEPA Web site http://www.

epa.gov/ogwdw/dwh/c-soc/atrazine.html). The Federal MCL 

in drinking water for atrazine is 3.0 μg/L as an annual average 

(U.S. Environmental Protection Agency, 2006a). The USEPA 

continues to investigate whether atrazine should be listed as a 

carcinogen (USEPA Web site http://www.cdc.gov/nasd/docs/

d001601-d001700/d001664/d001664.html).

Atrazine was detected in about 96 percent of the surfacewater samples collected for this study and exceeded the 

Federal MCL of 3.0 μg/L in about 31 percent of the samples 

analyzed for triazine herbicides (table 1). Average rather than 

median concentrations of atrazine are discussed in this report 

to facilitate a direct comparison of measured and computed 

atrazine concentrations to the Federal MCL, which is defined 

as an annual average. The summary of concentrations of 

atrazine in surface-water samples collected from 1995 through 

2005 at the two monitoring sites on the Little Arkansas River 

had an average concentration of 3.7 μg/L, which exceeded the 

MCL (table 1). The average atrazine concentration in water 

samples collected from the Little Arkansas River was 3.1 μg/L 

near Halstead and 3.5 μg/L near Sedgwick, both exceeded the 

MCL (table 1). Atrazine (triazine by ELISA) concentrations in 

water samples collected from the Little Arkansas River were 

as large as 50 μg/L near Halstead and as large as 40 μg/L near 

Sedgwick (table A-6). Atrazine concentrations larger than the 

MCL of 3.0 μg/L generally occur in the Little Arkansas River 

during late spring to early fall. Atrazine concentrations in 

treated stream water from the Sedgwick recharge site were as 

large as 6.7 μg/L, but the average concentration was 0.52 μg/L 

(table A-6). 

Regression models for computing concentrations of atrazine in the Little Arkansas River were developed using specific conductance measurements in the stream and day of year 

(Christensen and others, 2003). The largest concentrations 

computed for 1999-2005 were about 23 μg/L near Halstead 

and about 18 μg/L near Sedgwick (USGS Web site http:nrtwq.

usgs.gov/ks/). Duration curves of computed atrazine concentrations exceeded the MCL of 3.0 μg/L about 24 percent of the 

time from 1999 through 2005 in the Little Arkansas River near 

Halstead and 28 percent of the time near Sedgwick (fig. 23).

In groundwater, the percentage of samples with atrazine 

detections ranged from 0 percent in water from the prototype 

wells to about 55 percent in water from the shallow index 

wells (table 2). Average atrazine concentrations were much 

less than 3.0 μg/L in both the shallow and deep parts of the 

aquifer (table A-7). However, atrazine was detected in about 

55 percent of the samples collected from the shallow wells, 

which indicates infiltration from field applications. 

The largest atrazine concentration in groundwater in the 

study area was 2.2 μg/L in water from well EB-145-A1 (table 

A-7). This well is located immediately adjacent to the Little 

Arkansas River and is affected by infiltrating water (Schmidt 

and others, 2007). Schmidt and others (2007) indicated that 
56 Water Quality in the Equus Beds Aquifer and the Little Arkansas River, South-Central Kansas 

These bacteria indicate the potential for pathogens that may 

cause diarrhea, nausea, headaches, and abdominal cramps, and 

may pose a special health risk for infants, young children, and 

people with compromised immune systems (U.S. Environmental Protection Agency, 2005).

Total Coliform 

The USEPA Federal Maximum Contaminant Level Goal 

(MCLG) in drinking water for total coliform bacteria is that no 

more than 5 percent of samples test positive during 1 month 

for water systems that collect at least 40 routine samples per 

month (U.S. Environmental Protection Agency, 2005). If 

fewer than 40 samples are collected per month, only 1 sample 

can test positive for total coliform. 

The median total coliform density of 1,700 colonies per 

100 milliliters (col/100 mL) for water samples collected from 

1995 through 2005 at the two surface-water monitoring sites 

on the Little Arkansas River (table 1) was much larger than the 

MCLG for total coliform of 0 col/100 mL. About 93 percent of 

the samples collected from the two sites on the Little Arkansas 

River had total coliform detections (table 1), which indicates 

that the MCLG for total coliform was rarely met at these sites. 

atrazine may be moving with the shallow groundwater into the 

deep part of the aquifer at well EB-145-P-D5. 

Bacterial and Viral Indicators

Measuring the concentrations or densities of bacterial 

indicators and viruses in water is challenging because these 

organisms depend on specific conditions for growth. Additionally, the presence of bacteria and viruses in water is affected 

by runoff into waterways; therefore, sampling must quantify 

concentrations during storm runoff to describe the variability 

in surface water. 

To indicate the presence of disease-causing organisms 

in water, a bacterial indicator such as coliform is measured. 

Fecal coliform and Escherichia coli (E. coli) are two types of 

coliform bacterial indicators that come only from the intestines and waste material of warm blooded animals. E. coli are 

a specific type of fecal coliform. They are carried into water 

from septic systems, sewer pipes, wastewater treatment plants, 

farms, and yards. The presence of fecal coliform and E. coli

indicates that the water may be contaminated with human or 

animal wastes and may indicate that other harmful bacteria or 

viruses are present (Dufour and others, 1981; Dufour, 1984). 

0.01

0.1

1

10

100

0 20 40 60 80 100

07143672 Little Arkansas River at Highway 50 near Halstead, Kansas

07144100 Little Arkansas River near Sedgwick, Kansas

PERCENTAGE OF TIME INDICATED VALUE WAS EQUALLED OR EXCEEDED

COMPUTED ATRAZINE CONCENTRATION, IN MICROGRAMS PER LITER 

U.S Environmental Protection Agency (2006a) Maximum Contaminant Level (3.0 micrograms per liter) 

Figure 23. Duration curves of computed dissolved atrazine concentrations, 1999–2005, Little Arkansas River near Halstead and near 

Sedgwick, Kansas.
Water Quality in the Equus Beds Aquifer and Little Arkansas River, 1995–2005 57

Coliform detections in water samples collected from the Little 

Arkansas River during this period were as large as 2,000,000 

col/100 mL near Halstead and as large as 9,000,000 col/100 

mL near Sedgwick (table A-7). Large detections in surface 

water probably resulted from municipal wastewater discharge 

or runoff from livestock-producing areas. These large bacterial 

indicator densities are typical in central and eastern Kansas 

streams, especially during runoff conditions (Kansas Department of Health and Environment, 2006a,b). The median total 

coliform detections was 80 col/100 mL in treated source water 

at the Sedgwick recharge site during the 1997 through 2000 

recharge demonstration period; however, total coliform detections as large as 7,000 col/100 mL occurred in some samples 

(table A-7). Methods were not available to compute total coliform from continuously monitored constituents in the Little 

Arkansas River.

Total coliform densities in groundwater were much less 

than in samples from the Little Arkansas River (table A-7). 

Total coliform detections exceeded the USEPA Federal MCLG 

of 0 colonies in water samples from 95 percent of the shallow 

index wells and in 87 percent of the deep index wells in the 

Equus Beds aquifer. Many of these detections were in the first 

samples collected from the wells after they were developed, 

indicating that at least some of these detections may be related 

to drilling. Almost all wells sampled for this study had at least 

1 sample with a total coliform detection; however, the median 

densities for most of these wells were less than 1 col/100 mL 

(table A-7). The largest total coliform bacteria detection in the 

shallow part of the aquifer was 636 col/100 mL at background 

well TH-08-A3, and the largest total coliform bacteria detection in the deep aquifer was 224 col/100mL at ASR prototype 

well DW-TW-08 (table A-7). No specific areal distribution 

pattern was observed for total coliform detections in the study 

area for either part of the aquifer. 

Fecal Coliform

No USEPA Federal drinking-water criterion for fecal 

coliform bacteria has been established for drinking water. 

However, the State of Kansas had established recreational-use 

guidelines for water in Kansas streams of 200 col/100 mL for 

primary contact (swimming) during April 1 through October 

31 of each year and 2,000 col/100mL for primary contact 

during the rest of the year and for secondary contact (boating 

or wading) (Kansas Department of Health and Environment, 

2001). 

Median fecal coliform bacteria densities in water samples 

collected from 1995 through 2005 at the two sites on the 

Little Arkansas River were 860 col/100 mL for April through 

October and 170 col/100 mL for November through March 

(table 1). About 76 percent of the samples collected from the 

Little Arkansas River for April through October exceeded 

the criterion, and about 16 percent of the samples collected 

exceeded the criterion during November-March from 1995 

through 2005 (table 1). Although fecal coliform bacteria were 

detected at densities as large as 3,200 col/100 mL in treated 

source water collected at the Sedgwick recharge site during the 

1997 through 2000, the median fecal coliform bacteria density 

of 120 col/100 mL in samples from this site was less than the 

April through October primary contact criterion (table A-7).

Concentrations (or densities) of fecal coliform bacteria 

can be computed using continuous measurements of turbidity in streams (Rasmussen and Ziegler, 2003). The duration 

curves for the Little Arkansas River near Halstead (fig. 24) 

show that computed fecal coliform concentrations exceeded 

the primary contact recreational criterion about 71 percent of 

the time and exceeded the secondary contact recreational criterion about 18 percent of the time. At the Little Arkansas River 

near Sedgwick (fig. 24), computed fecal coliform concentrations exceeded the primary contact recreational criterion about 

51 percent of the time and exceeded the secondary contact 

recreational criterion about 15 percent of the time. 

The fecal coliform criterion does not apply to groundwater. Fecal coliform bacteria were rarely detected in water from 

background, ASR prototype, or index wells (table A-7). Fecal 

coliform detections in the index wells may be related to drilling activities because the only detections generally occurred 

shortly after the wells were completed. Fecal coliform bacteria 

may be detected more commonly in water from wells associated with the Halstead and Sedgwick recharge sites and may 

be associated with artificial recharge activities during the 

demonstration project from 1997 through 2002. However, all 

wells associated with the Halstead and Sedgwick recharge 

sites had median densities of fecal coliform bacteria of less 

than 1 col/100 mL (table A-7). Bacterial indicators that reach 

groundwater are expected to die off because they require dissolved oxygen to remain viable and there is little dissolved 

oxygen in groundwater.

Escherichia Coli

E. Coli is a specific type of fecal coliform bacteria. There 

also is no USEPA Federal drinking-water criterion for E. coli

bacteria; however, in 2004 the State of Kansas established 

surface-water recreational-use criteria. The criteria for publicly 

accessible (Class B) Kansas streams with flows of at least 1 

ft3

/s require that the geometric mean of at least five samples 

collected during separate 24-hour periods within a 30-day 

period not exceed 262 colony forming units per 100 milliliters 

(CFU/100 mL) for primary contact during April 1 through 

October 31 of each year and 2,358 CFU/100 mL for primary 

contact during the rest of the year; for secondary contact, the 

geometric mean will not exceed 2,358 CFU/100 mL at any 

time of year (Kansas Department of Health and Environment, 2004). For the purposes of this report, CFU/100 mL are 

equivalent to colonies per 100 mL.

Median E. coli bacteria densities in water samples collected from 1995 through 2005 at the two sites on the Little 

Arkansas River were 215 col/100 mL for April through 

October and 345 col/100 mL for November through March 

(table 1). Of the samples collected from the Little Arkansas 

River from 1995 through 2005, about 48 percent of those 
58 Water Quality in the Equus Beds Aquifer and the Little Arkansas River, South-Central Kansas 

The recreational-use criteria for E. coli do not apply 

to groundwater, and only a few groundwater samples were 

analyzed for E. coli. None of the analyzed groundwater 

samples had detections of E. coli that exceeded 1 col/100 mL 

(table A-7).

Viral Indicators

Viral indicators Clostridium perfringens and E. coli 

coliphage were analyzed in water samples from the Little 

Arkansas River and selected groundwater samples. Clostridium perfringens was detected at concentrations from 120 

to 360 col/100 mL, and E. coli coliphage was detected at 

concentrations varying from 40 to 1,300 plaques per 100 mL 

(pfu/100 mL) in storm-water samples from the Little Arkansas 

River (table A-7). These viral indicators were not detected in 

any samples of groundwater. These data indicate that natural 

infiltration of water through the soil removes viral indicator 

organisms. 

collected during April-October exceeded the public-access 

primary contact standard for E. coli of 262 col/100 mL. None 

of the samples collected from the Little Arkansas River during 

November through March exceeded the public-access primary 

and secondary standard for E. coli of 2,358 col/100 mL (table 

1). The treated source water at the Sedgwick recharge site 

exceeded the April through October primary contact standard 

for E. coli once (October 2000) out of two samples collected 

(table A-7). 

Densities of E. coli bacteria were computed using continuous measurements of turbidity in streams (Rasmussen 

and Ziegler, 2003). The duration curve for the Little Arkansas 

River near Halstead (fig. 25) shows that from 1999 through 

2005 computed E. coli concentrations exceeded the publicaccess primary contact recreational criterion about 54 percent 

of the time and exceeded the public-access secondary contact 

recreational criterion about 11 percent of the time. At the 

Little Arkansas River near Sedgwick from 1999 through 2005, 

computed E. coli densities exceeded the public-access primary 

contact recreational criterion about 40 percent of the time and 

exceeded the public-access secondary contact recreational criterion about 12 percent of the time (fig. 25). Computed E. coli

data and regression models are available on the World Wide 

Web at http://nrtwq.usgs.gov/ks/ .

1

10

100

1,000

10,000

100,000

0 20 40 60 80 100

07143672 Little Arkansas River at Highway 50 near Halstead, Kansas

07144100 Little Arkansas River near Sedgwick, Kansas

PERCENTAGE OF TIME INDICATED VALUE WAS EQUALLED OR EXCEEDED

Kansas Department of Health and Environment (2001) annual secondarycontact and November-March primary-contact standard

(2,000 colonies per 100 milliliters)

Kansas Department of Health and Environment

(2001) April-October primary-contact standard

(200 colonies per 100 milliliters)

COMPUTED FECAL COLIFORM BACTERIA DENSITY, IN COLONIES PER 100 MILLILITERS

Figure 24. Duration curves of computed fecal coliform bacteria densities, 1999–2005, Little Arkansas River near Halstead and near 

Sedgwick, Kansas.
Summary and Conclusions 59

Summary and Conclusions

Artificial recharge of the Equus Beds aquifer in southcentral Kansas using runoff from the Little Arkansas River 

was first proposed in 1956 and was one of the many options 

considered by the city of Wichita to preserve its water supply. 

Declining aquifer water levels of as much as 50 ft exacerbated 

concerns about future water availability and enhanced migration of saltwater from past oil and gas activities near Burrton 

and from the Arkansas River into the aquifer. Since Wichita 

changed water-management strategies and decreased pumping from the Equus Beds aquifer in 1992, water storage in the 

aquifer recovered by about 50 percent. This recovery is the 

result of increased reliance on Cheney Reservoir for Wichita 

water supply, decreased aquifer pumping, and larger than 

normal precipitation. Accompanying the water-level recovery, 

the water-level gradient in the aquifer decreased from about 12 

ft/mi in 1992 to about 8 ft/mi in January 2006. 

Artificial recharge using runoff from the Little Arkansas 

River was one of the many options considered to preserve 

the city’s water supply in the Equus Beds aquifer since first 

proposed in 1956. Demonstration recharge sites were operated 

from 1995-2002 near Halstead and Sedgwick to evaluate the 

feasibility of artificially recharging the aquifer using the Little 

Arkansas River as source water.

Water quality within the Little Arkansas River was 

defined using data from two real-time surface-water-quality 

sites and discrete samples. Water quality in the Equus Beds 

aquifer was defined using sample analyses collected at 38 

index sites, each with a well completed in the shallow and 

deep parts of the Equus Beds aquifer. In addition, data were 

collected at diversion well sites, recharge sites, background 

wells, and prototype wells for the aquifer storage and recovery 

project. Samples were analyzed for major ions, nutrients, trace 

metals, radionuclides, organic compounds, and bacterial and 

viral indicators. Federal and State drinking-water criteria were 

used to evaluate the quality of water in the aquifer.

Constituents of concern for artificial recharge are those 

that frequently (more than 5 percent of samples) exceed 

Federal and State drinking-water criteria in water samples 

from surface water and the aquifer. Constituents of concern for 

artificial recharge are major ions (sulfate, chloride), nutrients 

(nitrite plus nitrate), trace elements (arsenic, iron, and manganese), triazine herbicides (atrazine), and fecal bacterial 

indicators. Water chemistry in the surface water and groundwater are controlled by the geology of the underlying bedrock 

and aquifer materials, the hydrologic (effective porosity) and 

geochemical (oxidation-reduction potential) properties of the 

1

10

100

1,000

10,000

100,000

0 20 40 60 80 100

07143672 Little Arkansas River at Highway 50 near Halstead, Kansas

07144100 Little Arkansas River near Sedgwick, Kansas

PERCENTAGE OF TIME INDICATED VALUE WAS EQUALLED OR EXCEEDED

Kansas Department of Health and Environment (2004) annual secondarycontact and November-March primary-contact standard

(2,358 colonies per 100 milliliters)

Kansas Department of Health and Environment

(2004) April-October primary-contact standard

(262 colonies per 100 milliliters)

COMPUTED ESCHERICHIA COLI DENSITY, IN COLONIES PER 100 MILLILITERS

Figure 25. Duration curves of computed Escherichia coli bacteria, 1999–2005; Little Arkansas River near Halstead and near Sedgwick, 

Kansas. 
60 Water Quality in the Equus Beds Aquifer and the Little Arkansas River, South-Central Kansas 

(6 percent of the study area), whereas at depths of more than 

80 feet, average arsenic concentrations exceeded the MCL in 

34 percent of the wells (35 percent of the study area). Average 

arsenic concentrations exceeding the MCL in the shallow parts 

of the aquifer generally were located in the northern parts 

of the study area where more clay is present in the aquifer 

materials. These areas also correspond to the areas that had 

water-level declines of nearly 50 ft that have recovered by 

almost 20 ft. The larger arsenic concentrations in deep wells 

were most common in areas with reducing conditions where 

the oxidation-reduction potential (ORP) was less than 250 mV.

Other dissolved trace elements of concern in the study 

area were iron and manganese, which exceeded the USEPA 

Federal SDWR in both surface and groundwater. In the Little 

Arkansas River, dissolved iron concentrations exceeded the 

Federal SDWR of 300 μg/L only during one summer, and 

manganese concentrations exceeded the Federal SDWR of 50 

μg/L about half the time. In the shallow parts of the aquifer, 

average iron concentrations exceeded the Federal SDWR in 

about 44 percent of the study area, and average manganese 

concentrations exceeded the Federal SDWR in about 60 percent of the study area. In the deep parts of the aquifer, average 

iron concentrations were exceeded in about 44 percent of the 

area, and average manganese concentrations were exceeded 

throughout 97 percent of the area. Areas with the largest concentrations of both iron and manganese corresponded to areas 

with the largest water-level declines that have subsequently 

recovered and the areas with the more chemically reducing 

conditions. 

The areal distribution of larger dissolved arsenic, iron, 

and manganese concentrations were similar. Larger naturallyoccurring concentrations of arsenic, iron, and manganese in 

groundwater are associated with more reducing conditions, 

areas where more clay is present in the aquifer material, 

and areas that had large water-level declines and subsequent 

recovery. Effects of artificial recharge on natural dissolved 

concentrations of arsenic in the aquifer potentially can be 

minimized by maintaining the oxidation-reduction potential 

as near 1995–2005 baseline conditions as possible. However, 

in many areas of the aquifer, especially the deeper parts, the 

natural geochemical conditions are conducive to large arsenic 

concentrations. It may be possible to use artificial recharge of 

oxygenated water to create a less reducing geochemical environment, decreasing some of the arsenic and iron dissolved in 

the water, potentially improving the overall water quality in 

the aquifer.

Atrazine was the most commonly detected organic 

compound in the study area. The Federal MCL for atrazine in 

drinking water is 3 mg/L an annual average. Computed concentrations of atrazine in the Little Arkansas River exceeded 

the Federal MCL value of 3.0 mg/L about 27 percent of the 

time, mostly during the late spring to early fall. Atrazine was 

detected in about 55 percent of the samples collected from 

shallow wells, which indicates infiltration from field applications to the shallow groundwater, but all concentrations were 

much less than the MCL. 

aquifer, and the effects of humans related to past oil and gas 

activities and agriculture. 

Sulfate concentrations in water samples from the Little 

Arkansas River rarely exceeded Federal secondary drinking 

water regulation (SDWR) of 250 milligrams per liter (mg/L). 

Sulfate concentrations in groundwater were exceeded in about 

18 percent of the wells in the shallow (less than or equal to 80 

feet deep) parts of the aquifer and in about 13 percent of the 

wells in the deep parts the aquifer. Larger sulfate concentrations were associated with parts of the aquifer with the largest 

water-level declines. Water-quality changes in the Equus Beds 

aquifer likely were caused by dewatering and oxidation of 

aquifer material that subsequently resulted in increased sulfate 

concentrations as water levels recovered. 

The primary sources of chloride to the Equus Beds 

aquifer are from past oil and gas activities near Burrton and 

from the Arkansas River. Computed chloride concentrations in 

the Little Arkansas River near Halstead exceeded the Federal 

SDWR of 250 mg/L about 27 percent of the time (primarily during low-flow conditions). Chloride concentrations in 

groundwater exceeded 250 mg/L in about 8 percent or less of 

the study area, primarily near Burrton and along the Arkansas 

River. Chloride in groundwater near Burrton has migrated 

downgradient about 3 miles during the past 40 to 45 years. 

The downward and horizontal migration of the chloride is 

controlled by the hydraulic gradient in the aquifer, dispersion 

of chloride, and discontinuous clay layers that can inhibit 

further downward migration. Chloride in the shallow parts of 

the Equus Beds aquifer migrated less than 0.5 mile during the 

past decade. Migration is slower because of the decrease in the 

hydraulic gradient since 1992. On the basis of these results, 

artificial recharge (especially at depths of 100 to 150 feet) 

could create an effective barrier to saltwater migration. 

Nutrients, such as nitrite plus nitrate (hereinafter referred 

to as nitrate), are a water-quality concern because of the predominantly agricultural land use in the 150-square-mile study 

area. All nitrate concentrations in water samples collected at 

the two surface-water monitoring sites on the Little Arkansas 

River from 1995 through 2005 were less than the Federal 

maximum contaminant level (MCL) of 10 mg/L for nitrate. 

Groundwater sampling results indicated that average nitrate 

concentrations exceeding the MCL were detected in 13 percent 

of the wells in 9 percent of the shallow parts of the aquifer in 

the study area. Little nitrate is present in the deeper parts of 

the aquifer because of chemical reducing conditions. Larger 

nitrate concentrations in shallow and deep groundwater likely 

were at least partly controlled by more rapid percolation from 

agricultural land uses in these areas of larger effective porosity 

and geochemical controls, especially in deep groundwater. 

Several trace elements frequently exceeded drinkingwater criteria, including arsenic, iron, and manganese. 

Computed arsenic concentrations in the Little Arkansas River 

exceeded the Federal drinking-water MCL of 10 micrograms 

per liter (μg/L) about 14 percent of the time primarily during 

low-flow conditions. In shallow groundwater, average arsenic 

concentrations exceeded the MCL in 10 percent of the wells 
Selected References 61

Large concentrations of coliform bacterial indicators 

(total coliform, fecal coliform, and Escherichia coli) were 

detected in all water samples from the Little Arkansas River. 

These large bacterial indicator densities are typical in central 

and eastern Kansas streams, especially during runoff conditions. Total coliform detections exceeded the USEPA Federal 

MCLG of 0 colonies in water samples from 95 percent of the 

shallow index wells and in 87 percent of the deep wells in 

the Equus Beds aquifer. Many of these detections were in the 

first samples collected from the wells after they were developed, indicating that at least some of these detections may 

be related to drilling. Almost all wells sampled for this study 

had at least 1 sample with a total coliform detection; however, 

the median densities for most of these wells were less than 1 

colony per100 mL. Viral indicators (Clostridium perfringens

and E. coli coliphage) were present in samples from the Little 

Arkansas River during storm runoff but were not detected in 

any samples of groundwater. These data indicated that natural 

infiltration of water through the soil removes bacterial and 

viral indicator organisms. 

Regression models for groundwater were developed to 

assist in estimation of water-quality constituents. Regressions 

between specific conductance and sulfate, specific conductance and chloride, and ORP and arsenic resulted in coefficients of determination greater than 0.50, which indicates 

that the use of specific conductance and ORP as explanatory 

variables is useful for estimating concentrations of sulfate, 

chloride, and arsenic in groundwater. These regression models 

may be useful for monitoring water quality in the aquifer after 

the full-scale recharge project has begun. 

Water quality in surface water and groundwater is controlled by the geology of the underlying bedrock and aquifer 

materials, the hydraulic permeability (porosity) and geochemical (oxidation and reduction) properties of the aquifer, and 

the effects of humans related to past oil and gas activities and 

agriculture. When the proposed full-scale artificial recharge of 

the Equus Beds aquifer is implemented, changes in concentrations of water-quality constituents are expected. The increased 

water levels from artificial recharge are expected to slow 

the saltwater migration from the northwest and south of the 

study area, potentially limiting further chloride migration and 

improving the quality of water in the aquifer. Continued monitoring and interpretation of these recharge water-quality data 

relative to drinking-water criteria will help ensure the usable 

quality of water in the Equus Beds aquifer. 

Selected References

American Public Health Association, American Water Works 

Association, and Water Environment Federation, 2005, 

Standard methods for examination of water and wastewater 

(20th ed.): American Public Health Association, part 9222B, 

p. 9–57 to 9–62.

Armon, R., and Payment, P., 1988, A modified m-CP medium 

for enumerating Clostridium perfringens from water 

samples: Canadian Journal of Microbiology, v. 34, p. 78–79.

Aucott, W.R., Myers, N.C., and Dague, B.J., 1998, Status of 

groundwater levels and storage in the Wichita well field 

area, south-central Kansas, 1997: U.S. Geological Survey 

Water-Resources Investigations Report 98–4095, 15 p.

Bauder, T.A., Waskom, R.M., and Davis, J.G., 2007, Irrigation 

water quality criteria: Colorado State University Extension, 

information available on Web, accessed July 14, 2008, at 

http://www.ext.colostate.edu/PUBS/crops/00506.html.

Bisson, J.W.,and Cabelli, V.J., 1979, Membrane filter enumeration method for Clostridium perfringens: Applied and 

Environmental Microbiology, v. 37, no. 1, p. 55–66.

Bisson, J.W., and Cabelli, V.J., 1980, Clostridium perfringens

as a water pollution indicator: Journal of the Water Pollution 

Control Federation, v. 52, no. 2, p. 241–248.

Britton, L.J., and Greeson, P.E., eds, 1987, Methods for collection and analysis of aquatic biological and microbiological 

samples: U.S. Geological Survey Techniques of WaterResources Investigations, book 5, chap. A4, various pagination, accessed March 13, 2008, at http://pubs.usgs.gov/twri/

twri5a4/html/pdf.html.

Burns and McDonnell, 1996, Equus Beds Groundwater 

Recharge Demonstration Project: Kansas City, Missouri, 

Burns and McDonnell Engineering Consultants, prepared 

for the city of Wichita Water and Sewer Department, various pagination.

Christensen, V.G., Jian Xiaodong, and Ziegler, A.C., 2000, 

Regression analysis and real-time water-quality monitoring 

to estimate constituent concentrations, loads, and yields in 

the Little Arkansas River, south-central Kansas, 1995–99: 

U.S. Geological Survey Water-Resources Investigations 

Report 00–4126, 36 p.

Christensen, V.G., Ziegler, A.C., Rasmussen, P.P., and Jian 

Xiaodong, 2003, Continuous real-time water-quality monitoring of Kansas streams, in Proceedings of 2003 Spring 

Specialty Conference on Agricultural Hydrology and Water 

Quality, May 12–14, 2003, Kansas City, Missouri: Middleburg, Virginia, American Water Resources Association 

Technical Publication Series No. TPS-03-1, compact disc. 

Dufour, A.P., 1984, Bacterial indicators of recreational water 

quality: Canadian Journal of Public Health, v. 75, no. 1, p. 

49–56.

Dufour, A.P., Strickland, E.R., and Cabelli, V.J., 1981, 

Membrane filter method for enumerating Escherichia coli: 

Applied and Environmental Microbiology, v. 41, no. 5, p. 

1,152–1,158.
62 Water Quality in the Equus Beds Aquifer and the Little Arkansas River, South-Central Kansas 

Juracek and Hansen, 1995, Digital hypsography maps created from 1:100,000-scale digital line Graph hypsography 

data for Kansas: U.S. Geological Survey Open-File Report 

95–448, digital data set.

Kansas Department of Agriculture, 2006, Kansas farm facts 

2006: Topeka, Kansas, 103 p.

Kansas Department of Health and Environment, 2001, Kansas 

Administrative Regulation, article 28-16-28e, Surface water 

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Appendix 65

Appendix
66 Water Quality in the Equus Beds Aquifer and the Little Arkansas River, South-Central Kansas Table A–1. Data-collection sites for the Equus Beds Groundwater Recharge Project, south-central Kansas, 1995–2005. [USGS, U.S. Geological Survey; NAVD 88, North American Vertical Datum of 1988; NA, not applicable] Data-collection site number (fig. 6) USGS site identification number Site name Gage datum or altitude of top of well casing (feet above NAVD 88) Approximate well depth (feet) Approximate depth of screened interval (feet) Surface-water monitoring sites 07143672 07143672 Little Arkansas River at Highway 50 near Halstead, Kansas 1,370.55 NA NA 07144100 07144100 Little Arkansas River near Sedgwick, Kansas 1,340.00 NA NA Halstead diversion well site Diversion well 380031097311001 Diversion well at TH-04-95 NA 136 76–136 EB-145-A11 380028097311001 23S 02W 34ADD 01 TH-04-A1 EB-145-A1 1,392.87 48 38–48 EB-145-A21 380028097310901 23S 02W 34ADDA01 TH-04-A2 EB-145-A2 1,392.68 47 37–47 EB-145-A31 380028097311101 23S 02W 34ADDB01 TH-04-A3 EB-145-A3 1,392.82 70 60–70 EB-145-A42 380027097311401 23S 02W 34ADCD01 TH-04-A4 EB-145-A4 1,394.00 60 50–60 EB-145-A52 380025097312701 23S 02W 34ACDC01 TH-04-A5 EB-145-A5 1,394.26 43 32–42 EB-145-P-D53 380028097311002 23S 02W 34ADDA02 EB-145-P-D5 1,392.40 120 112–117 Halstead recharge site Source water diverted for recharge 380051097335501 Source water diverted for recharge NA NA NA SMW-H44 380051097335601 23S 02W 29CDDC01 Shallow monitoring well SMW-H4 1,429.22 29 19–29 SMW-H144 380053097335101 23S 02W 29CDDD01 Shallow monitoring well SMW-H14 1,424.25 27 17–27 DMW-H15 380052097335701 23S 02W 29CDDC01 Deep monitoring well DMW-H1 1,428.16 220 210–220 DMW-H135 380053097335102 23S 02W 29CDDD02 Deep monitoring well DMW-H13 1,424.31 220 210–220 Sedgwick recharge site Treated stream water 375331097285301 Diverted water Sedgwick recharge site NA NA NA SMW-S116 375327097285401 25S 01W 07BCCC01 Shallow monitoring well SMW-S11 1,384.64 59 49–59 SMW-S136 375332097284801 25S 01W 07BCCA01 Shallow monitoring well SMW-S13 1,384.90 34 24–34 DMW-S147 375332097284802 25S 01W 07BCCA02 Deep monitoring well DMW-S14 1,384.00 190 180–190 DMW-S107 375327097285402 25S 01W 07BCCC02 Deep monitoring well DMW-S10 1,385.52 195 185–195 Background wells EB-142-A3 375300097253501 25S 01W 10CCCC01 Sedgwick well A3 EB-142-A3 1,363.65 58 47–57 Sedgwick well 375259097252901 25S 01W 15BBBA01 Sedgwick well 1,370.38 49 39–49 City well-Sedgwick 375456097260901 24S 01W 33DDA 01 City well-Sedgwick NA NA NA

TH-02-95 380237097324401 23S 02W 16CDD 01 TH-02-95 1,403.04 54 44–54

TH-06-95 375304097291301 24S 02W 01DCC 01 TH-06-95 1,381.87 41 31–41

TH-10-95 380424097343801 23S 02W 06DDD 01 TH-10-95 1,409.49 59 49–59

TH-12-95 375140097243301 24S 01W 23BCC 01 TH-12-95 1,359.00 50 40–50

TH-08-A1 375628097270201 24S 01W 29ABAA01 TH-08-A1 1,359.58 40 30–40

TH-08-A2 375628097270401 24S 01W 29ABAB01 TH-08-A2 1,379.26 53 43–53

TH-08-A3 375628097270801 24S 01W 29ABAB01 TH-08-A3 1,379.96 59 48–58

TH-08-A4 375628097271001 24S 01W 29ABBA01 TH-08-A4 1,380.08 58 46–56

TH-08-A5 375628097271701 24S 01W 29BAAA01 TH-08-A5 1,378.53 53 42–52

Alta Mills 380643097353001 22S 02W 30BCBB01 Alta Mills 1,416.07 40 30–40
Appendix 67

Table A–1. Data-collection sites for the Equus Beds Groundwater Recharge Project, south-central Kansas, 1995–2005.—Continued[USGS, U.S. Geological Survey; NAVD 88, North American Vertical Datum of 1988; NA, not applicable]

Data-collection 

 site number 

(fig. 6) 

USGS 

site identification 

number

Site name

Gage datum or altitude 

of top of well casing 

(feet above NAVD 88)

Approximate 

well depth 

(feet)

Approximate depth 

of screened interval 

(feet)

Aquifer storage and recovery prototype wells

DW-TW-01 380329097334601 23S 02W 08DCCD01 DW-TW-01 NA 148 108–148

DW-TW-02 380333097335001 23S 02W 08DCCB01 DW-TW-02 NA 148 108–148DW-TW-03 380336097335801 23S 02W 08CDAC01 DW-TW-03 NA 160 100–160DW-TW-04 380338097340201 23S 02W 08CDBA01 DW-TW-04 NA 140 100–140DW-TW-05 380344097340401 23S 02W 08CACC01 DW-TW-05 NA 145 105–145DW-TW-06 380356097340901 23S 02W 08BCDD01 DW-TW-06 NA 130 98–130DW-TW-07 380358097341301 23S 02W 08BCDB01 DW-TW-07 NA 138 98–138DW-TW-08 380404097342101 23S 02W 08BCBB01 DW-TW-08 1,407.00 124 85–124

DW-TW-09 380405097342501 23S 02W 08BCBB02 DW-TW-09 1,407.00 121 83–121

RRW-01 380329097363703 23S 03W 12CCCC03 RRW-01 NA 124 84–124

RRW-02 380235097363801 23S 03W 23AAAA01 RRW-02 NA 253 233–253RRW-03 380142097363601 23S 03W 25BBBB01 RRW-03 NA 189 169–189

Shallow index wells

IW-01A 380421097385001 23S 03W 03CCCC01 IW-01A 1,471.63 41 20–40

IW-02A 380329097363701 23S 03W 12CCCC01 IW-02A 1,451.82 27 16–26

IW-03A 380328097342501 23S 02W 17BBBB01 IW-03A 1,409.51 35 24–34

IW-04A 380130097385001 23S 03W 27BCBB01 IW-04A 1,446.77 29 10–30

IW-05A 380144097371101 23S 03W 23DCCC01 IW-05A 1,441.46 66 45–65

IW-06A 380143097344201 23S 02W 30AAAB01 IW-06A 1,434.70 69 47–67

IW-07A 380051097330901 23S 02W 28CCDC01 IW-07A 1,427.53 80 58–78

IW-08A 380016097384901 23S 03W 34CBCB01 IW-08A 1,441.79 38 18–38

IW-09A 375958097363801 24S 03W 02AAAA01 IW-09A 1,431.70 53 33–53

IW-10A 375959097344201 23S 02W 31DDCC01 IW-10A 1,435.45 78 58–78

IW-11A-2 375932097321301 24S 02W 03CBBB01 IW-11A-2 1,415.70 68 48–68

IW-12A 375958097300001 24S 02W 01BBBB01 IW-12A 1,390.59 40 20–40

IW-13A 375815097385001 24S 03W 09DDDD01 IW-13A 1,436.82 41 20–40

IW-14A 375748097363801 24S 03W 14ADDD01 IW-14A 1,424.93 53 33–53

IW-15A 375814097342701 24S 02W 18AAAA01 IW-15A 1,421.36 75 54–74

IW-16A 375814097324701 24S 02W 16BAAA01 IW-16A 1,405.02 66 45–65

IW-17A 375814097300001 24S 02W 13BBBB01 IW-17A 1,387.57 51 30–50

IW-18A 375642097385304 24S 03W 21DDAA04 IW-18A 1,434.66 28 8–28

IW-19A 375604097363601 24S 03W 25BCCB01 IW-19A 1,421.79 43 23–43

IW-20A 375630097342701 24S 02W 19DDDD01 IW-20A 1,416.74 46 25–45

IW-21A 375629097323501 24S 02W 21DCDC01 IW-21A 1,410.58 56 45–55

IW-22A 375629097293701 24S 02W 25BBAB01 IW-22A 1,387.70 54 33–53
68 Water Quality in the Equus Beds Aquifer and the Little Arkansas River, South-Central Kansas Table A–1. Data-collection sites for the Equus Beds Groundwater Recharge Project, south-central Kansas, 1995–2005.—Continued [USGS, U.S. Geological Survey; NAVD 88, North American Vertical Datum of 1988; NA, not applicable] Data-collection site number (fig. 6) USGS site identification number Site name Gage datum or altitude of top of well casing (feet above NAVD 88) Approximate well depth (feet) Approximate depth of screened interval (feet) Shallow index wells—Continued IW-23A 375629097274801 24S 01W 29BBBB01 IW-23A 1,381.66 66 45–65 IW-24A 375446097390701 24S 03W 33DDCC01 IW-24A 1,430.79 40 19–39 IW-25A 375445097365404 24S 03W 35DCDD04 IW-25A 1,419.69 30 9–29 IW-26A 375508097342401 24S 02W 32CBBB01 IW-26A 1,409.47 29 8–28 IW-27A 375434097321301 25S 02W 04AADA01 IW-27A 1,400.15 41 20–40 IW-28A 375420097300201 25S 02W 02ADDA01 IW-28A 1,389.50 63 41–61 IW-29A 375445097274801 24S 01W 32CCCC01 IW-29A 1,376.33 61 40–60 IW-30A 375258097340601 25S 02W 17BBAA01 IW-30A 1,376.79 27 6–26 IW-31A 375300097321101 25S 02W 15BBBB01 IW-31A 1,391.43 29 8–28 IW-32A 375247097300101 25S 02W 13BCBB01 IW-32A 1,381.45 25 5–25 IW-33A 375326097274501 25S 01W 08CBBB01 IW-33A 1,376.51 34 13–33 IW-34A 375300097255801 25S 01W 09DCDD01 IW-34A 1,366.61 45 25–45 IW-35A 375115097313601 25S 02W 22DCDC01 IW-35A 1,384.94 26 6–26 IW-36A 375115097294601 25S 02W 25BBAA01 IW-36A 1,376.72 25 5–25 IW-37A 375116097274701 25S 01W 20CCCC01 IW-37A 1,371.43 26 5–25 IW-38A 375141097253801 25S 01W 21DAAA01 IW-38A 1,370.40 44 23–43 Deep index wells IW-01C 380421097385002 23S 03W 03CCCC02 IW-01C 1,472.29 104 82–102 IW-02C 380329097363702 23S 03W 12CCCC02 IW-02C 1,451.90 97 75–95 IW-03C 380328097342502 23S 02W 17BBBB02 IW-03C 1,409.76 141 118–138 IW-04C 380130097385002 23S 03W 27BCBB02 IW-04C 1,446.84 217 194–214 IW-05C 380144097371102 23S 03W 23DCCC02 IW-05C 1,441.32 194 170–190 IW-06C 380143097344202 23S 02W 30AAAB02 IW-06C 1,434.57 121.75 100–120 IW-07C 380051097330902 23S 02W 28CCDC02 IW-07C 1,427.43 196 173–193 IW-08C 380016097384902 23S 03W 34CBCB02 IW-08C 1,441.66 161 138–158 IW-09C 375958097363802 24S 03W 02AAAA02 IW-09C 1,431.99 257 233–253

IW-10C 375959097344202 23S 02W 31DDCC02 IW-10C 1,435.32 177 155–175

IW-11C 375932097321302 24S 02W 03CBBB02 IW-11C 1,416.13 142 120–140

IW-12C 375958097300002 24S 02W 01BBBB02 IW-12C 1,390.61 78 56–76IW-13C 375815097385002 24S 03W 09DDDD02 IW-13C 1,436.85 102 80–100IW-14C 375748097363802 24S 03W 14ADDD02 IW-14C 1,424.93 153 130–150IW-15C 375814097342702 24S 02W 18AAAA02 IW-15C 1,421.43 213 188-208IW-16C 375814097324702 24S 02W 16BAAA02 IW-16C 1,404.83 129 106–126
Appendix 69

Table A–1. Data-collection sites for the Equus Beds Groundwater Recharge Project, south-central Kansas, 1995–2005.—Continued[USGS, U.S. Geological Survey; NAVD 88, North American Vertical Datum of 1988; NA, not applicable]

Data-collection 

 site number 

(fig. 6) 

USGS 

site identification 

number

Site name

Gage datum or altitude 

of top of well casing 

(feet above NAVD 88)

Approximate 

well depth 

(feet)

Approximate depth 

of screened interval 

(feet)

Deep index wells—Continued

IW-17C 375814097300002 24S 02W 13BBBB02 IW-17C 1,387.48 113 100–110

IW-18C 375642097385305 24S 03W 21DDAA05 IW-18C 1,434.50 86 65–85IW-19C 375604097363602 24S 03W 25BCCB02 IW-19C 1,421.42 86 65–85IW-20C 375630097342702 24S 02W 19DDDD02 IW-20C 1,416.18 163.1 140–160IW-21C 375629097323502 24S 02W 21DCDC02 IW-21C 1,410.91 92 70–90IW-22C 375629097293702 24S 02W 25BBAB02 IW-22C 1,387.55 138 115–135

IW-23C 375629097274802 24S 01W 29BBBB02 IW-23C 1,381.54 112 90–110

IW-24C 375446097390702 24S 03W 33DDCC02 IW-24C 1,430.67 160 137–157IW-25C 375445097365405 24S 03W 35DCDD05 IW-25C 1,419.46 76 65–75IW-26C 375508097342402 24S 02W 32CBBB02 IW-26C 1,409.61 200 188–198IW-27C 375434097321302 25S 02W 04AADA02 IW-27C 1,400.11 248 227–247

IW-28C 375420097300202 25S 02W 02ADDA02 IW-28C 1,389.56 176 155–175

IW-29C 375445097274802 24S 01W 32CCCC02 IW-29C 1,376.34 116 95–115

IW-30C 375258097340602 25S 02W 17BBAA02 IW-30C 1,376.81 122 100–120IW-31C 375300097321102 25S 02W 15BBBB02 IW-31C 1,391.64 230 204–224IW-32C 375247097300102 25S 02W 13BCBB02 IW-32C 1,381.79 163 140–160IW-33C 375326097274502 25S 01W 08CBBB02 IW-33C 1,376.50 122 100–120IW-34C 375300097255802 25S 01W 09DCDD02 IW-34C 1,366.91 125 103–123IW-35C 375115097313602 25S 02W 22DCDC02 IW-35C 1,384.87 118 96–116

IW-36C 375115097294602 25S 02W 25BBAA02 IW-36C 1,376.47 118 95–115

IW-37C 375116097274702 25S 01W 20CCCC02 IW-37C 1,371.60 129 107–127IW-38C 375141097253802 25S 01W 21DAAA02 IW-38C 1,370.18 80 58–78

1 Shallow monitoring wells within 500 feet of Little Arkansas River at diversion well site near Halstead.2 Shallow monitoring wells more than 500 feet from Little Arkansas River at diversion well site near Halstead.3 Deep monitoring well at diversion well site near Halstead.4 Shallow monitoring wells at Halstead recharge site near Halstead.5 Deep monitoring wells at Halstead recharge site near Halstead.6 Shallow monitoring wells at Sedgwick recharge site near Sedgwick.7 Deep monitoring wells at Sedgwick recharge site near Sedgwick.
70 Water Quality in the Equus Beds Aquifer and the Little Arkansas River, South-Central Kansas Table A–2. Constituents analyzed in water samples for the Equus Beds Groundwater Recharge Project, 1995–2005. [<, less than; μm, micron; ELISA, enzyme-linked immunosorbent assay; m-TEC, membrane-thermotolerant Escherichia coli; MF, membrane filter] Physical properties, dissolved and suspended solids, and suspended sediment (table A–3) Oxidation-reduction potential1 Specific conductance1 Alkalinity, dissolved1 Suspended sediment Turbidity1 Water temperature1 Dissolved solids1 Oxygen, dissolved1 Carbonate hardness, total Suspended solids, total1 pH1 Hardness1 Suspended sediment <63 μm Major ions and nutrients (table A–4) Calcium, dissolved1 Bromide, dissolved Nitrate, total Orthophosphate, dissolved Magnesium, dissolved1 Chloride, dissolved1 Nitrite plus nitrate, dissolved1 Orthophosphate as phosphorus, dissolved Potassium, dissolved1 Fluoride, dissolved Nitrite plus nitrate, total Organic carbon, total Sodium, dissolved1 Sulfate, dissolved1 Nitrite, dissolved Bicarbonate, dissolved1 Ammonia, dissolved Nitrite, total Carbonate, dissolved1 Nitrate, dissolved Phosphorous, total1 Trace elements (table A–5) Aluminum, dissolved Boron, dissolved Manganese, dissolved1 Thallium, dissolved Antinomy, dissolved Cadmium, dissolved Mercury, dissolved Vanadium, dissolved Arsenate, dissolved Chromium, dissolved Molybdenum, dissolved Zinc, dissolved Arsenic, dissolved1 Copper, dissolved Nickel, dissolved Dimethylarsinate, dissolved Arsenite, dissolved Cyanide, dissolved Selenium, dissolved Monomethylarsonate, dissolved Barium, dissolved Iron, dissolved1 Silver, dissolved Beryllium, dissolved Lead, dissolved Strontium, dissolved Organic compounds (table A–6) 1,2-Diphenylhydrazine, total3 2-Chloro-6-ethylamino-4-amino-s-triazine, total 9H-Fluorene, total3 alpha-Hexachlorocyclohexane, total3 1-Naphthol, dissolved2,3 2-Chloroethyl vinyl ether, total3 Acenaphthene, total3 Ametryn, dissolved 2,4,5-T, dissolved3 2-Chloronaphthalene, total3 Acenaphthylene, total3 Ametryn, total 2,4,5-T, total3 2-Chlorophenol, total3 Acetochlor ethanesulfonic acid, dissolved2 Aminomethylphosphonic acid, dissolved2 2,4,6-Trichlorophenol, total3 2-Ethyl-6-methylaniline, dissolved Acetochlor oxanilic acid, dissolved2 Amoxicillin, dissolved3 2,4-D methyl ester, dissolved3 2-Hydroxy-4-isopropylamino-6-amino-s-triazine, dissolved2 Acetochlor sulfynilacetic acid, dissolved3 Ampicillin, dissolved3 2,4-D, dissolved 2-Hydroxy-4-isopropylamino-6-ethylamino-s-triazine, dissolved Acetochlor, dissolved Anhydrochlortetracycline, dissolved3 2,4-D, total 2-Hydroxy-6-ethylamino-4-amino-s-triazine, dissolved2,3 Acifluorfen, dissolved2,3 Anhydrotetracycline, dissolved2,3 2,4-DB, dissolved2,3 2-Methyl-4,6-dinitrophenol, dissolved2,3 Alachlor ethanesulfonic acid, dissolved2 Anthracene, total3 2,4-Dichlorophenol, total3 2-Methyl-4,6-dinitrophenol, total3 Alachlor oxanilic acid, dissolved2 Aroclor 1016 plus Aroclor 1242, total3 2,4-Dimethylphenol, total3 2-Nitrophenol, total3 Alachlor sulfynilacetic acid, dissolved3 Aroclor 1221, total3

2,4-Dinitrophenol, total3 3,3’-Dichlorobenzidine, total3 Alachlor, dissolved Aroclor 1232, total32,4-Dinitrotoluene, total3 3,4-Dichloroaniline, dissolved Alachlor, total Aroclor 1248, total32,6-Diethylaniline, dissolved2 3-Hydroxy carbofuran, dissolved2,3 Aldicarb sulfone, dissolved2,3 Aroclor 1254, total32,6-Dinitrotoluene, total3 3-Ketocarbofuran, dissolved3 Aldicarb sulfoxide, dissolved2,3 Aroclor 1260, total32-[(2-Ethyl-6-methylphenyl)-amino]-1-propanol, dissolved3 4-Bromophenyl phenyl ether, total3 Aldicarb, dissolved2,3 Atrazine, dissolved

2-Chloro-2’,6’-diethylacetanilide, dissolved 4-Chloro-2-methylphenol, dissolved3 Aldicarb, total3 Atrazine, total2-Chloro-4-isopropylamino-6-amino-s-triazine, dissolved 4-Chloro-3-methylphenol, total3 Aldrin, total3 Triazine screen, dissolved, ELISA (table A–7)2-Chloro-4-isopropylamino-6-amino-s-triazine, total 4-Chlorophenyl phenyl ether, total3 alpha-Endosulfan, total3 Triazine screen, total, ELISA (table A–7)2-Chloro-6-ethylamino-4-amino-s-triazine, dissolved 4-Nitrophenol, total3 alpha-Hexachlorocyclohexane, dissolved3 Azinphos-methyl oxygen analog, dissolved3
Appendix 71

Table A–2. Constituents analyzed in water samples for the Equus Beds Groundwater Recharge Project, 1995–2005.—Continued[<, less than; μm, micron; ELISA, enzyme-linked immunosorbent assay; m-TEC, membrane-thermotolerant Escherichia coli; MF, membrane filter]

Organic compounds (table A–6)—Continued

Azinphos-methyl, dissolved2,3 Chlordane (technical), total3 Diazinon, total Ethion, total3

Bendiocarb, dissolved3 Chlorimuron, dissolved3 Dibenzo[a,h]anthracene, total3 Ethoprop, dissolved2Benfluralin, dissolved2,3 Chlorodiamino-s-triazine, dissolved2 Dicamba, dissolved2,3 Fenamiphos sulfone, dissolved3Benomyl, dissolved3 Chlorodiamino-s-triazine, dissolved Dicamba, total Fenamiphos sulfoxide, dissolved3Bensulfuron-methyl, dissolved3 Chlorotetracycline, dissolved Dichlobenil, dissolved2,3 Fenamiphos, dissolved3Bentazon, dissolved2 Chlorothalonil, dissolved2 Dichlorprop, dissolved2,3 Fenuron, dissolved2,3Benzidine, total3 Chlorpyrifos oxygen analog, dissolved3 Dichlorprop, total3 Desulfinylfipronil amide, dissolved3Benzo[a]anthracene, total3 Chlorpyrifos, dissolved Dicrotophos, dissolved3 Fipronil sulfide, dissolved

Benzo[a]pyrene, total3 Chlorpyrifos, total3 Dieldrin, dissolved3 Fipronil sulfone, dissolved3

Benzo[b]fluoranthene, total3 Chrysene, total3 Dieldrin, total3 Fipronil, dissolved

Benzo[ghi]perylene, total3 Ciprofloxacin, dissolved3 Diethyl phthalate, total3 Flufenacet ethanesulfonic acid, dissolved3

Benzo[k]fluoranthene, total3 cis-Chlordane, total3 Dimethenamid ethanesulfonic acid, dissolved3 Flufenacet oxanilic acid, dissolved3Benzyl n-butyl phthalate, total3 cis-Permethrin, dissolved2,3 Dimethenamid oxanilic acid, dissolved3 Flufenacet, dissolved3beta-Endosulfan, total3 Clinafloxacin, dissolved3 Dimethenamid, dissolved Flumequine, dissolved2,3beta-Hexachlorocyclohexane, total3 Clopyralid, dissolved2,3 Dimethoate, dissolved2,3 Flumetsulam, dissolved

Bis(2-chloroethoxy)methane, total3 Cloxacillin, dissolved3 Dimethyl phthalate, total3 Fluometuron, dissolved2,3

Bis(2-chloroethyl) ether, total3 Cyanazine acid, dissolved Di-n-butyl phthalate, total3 Fluoranthene, total3Bis(2-chloroisopropyl) ether, total3 Cyanazine amide, dissolved Di-n-octyl phthalate, total3 Fonofos oxygen analog, dissolved3Bis(2-ethylhexyl) phthalate, total Cyanazine, dissolved Dinoseb, dissolved2,3 Fonofos, dissolved3Bromacil, dissolved Cyanazine, total Diphenamid, dissolved3 Fonofos, total3Bromacil, total Cycloate, dissolved3 Diphenamid, total3 Glufosinate, dissolved2,3Bromoxynil, dissolved2,3 Cycloate, total3 Disulfoton, dissolved2,3 Glyphosate, dissolved2Butachlor, total3 Cyfluthrin, dissolved3 Disulfoton, total3 Heptachlor epoxide, total3Butylate, dissolved Cypermethrin, dissolved3 Diuron, dissolved2 Heptachlor, total3Butylate, total3 Dacthal monoacid, dissolved3 Diuron, dissolved Hexachlorobenzene, total3Caffeine, dissolved Dimethyl tetrachloroterephthalate, dissolved2 Doxycycline, dissolved2,3 Hexachlorocyclopentadiene, total3Carbadox, dissolved2,3 Deethyl cyanazine acid, dissolved Endosulfan sulfate, total3 Hexazinone, dissolved

Carbaryl, dissolved2 Deethyl cyanazine amide, dissolved3 Endrin aldehyde, total3 Hexazinone, total3

Carbaryl, total3 Deethyl cyanazine, dissolved3 Endrin, total3 Imazaquin, dissolved

Carbofuran, dissolved2 delta-Hexachlorocyclohexane, total3 S-Ethyl dipropylthiocarbamate, dissolved2 Imazethapyr, dissolved3

Carbofuran, total3 Demeclocycline, dissolved2,3 Erythromycin, dissolved3 Imidacloprid, dissolved3Carbophenothion, total3 Demethyl fluometuron, dissolved3 Esfenvalerate, dissolved2,3 Indeno[1,2,3-cd]pyrene, total3Carboxin, total3 Desulfinylfipronil, dissolved Ethalfluralin, dissolved2 Iprodione, dissolved3Cefotaxime, dissolved3 Diazinon oxygen analog, dissolved3 Ethion monoxon, dissolved3 Isofenphos, dissolved3Chloramben methyl ester, dissolved3 Diazinon, dissolved Ethion, dissolved3 Isophorone, total3
72 Water Quality in the Equus Beds Aquifer and the Little Arkansas River, South-Central Kansas Table A–2. Constituents analyzed in water samples for the Equus Beds Groundwater Recharge Project, 1995–2005.—Continued [<, less than; μm, micron; ELISA, enzyme-linked immunosorbent assay; m-TEC, membrane-thermotolerant Escherichia coli; MF, membrane filter] Organic compounds (table A–6)—Continued Lincomycin, dissolved3 Nitrobenzene, total3 Picloram, total Sulfamethoxazole, dissolved3 Lindane, dissolved N-Nitrosodimethylamine, total3 Polychlorinated naphthalenes, total3 Sulfathiazole, dissolved2,3 Lindane, total3 N-Nitrosodi-n-propylamine, total3 Prometon, dissolved Sulfometuron, dissolved3 Linuron, dissolved2 N-Nitrosodiphenylamine, total3 Prometon, total3 Tebuthiuron, dissolved2 Lomefloxacin, dissolved3 Norfloxacin, dissolved2,3 Prometryn, dissolved Terbacil, dissolved2 Malaoxon, dissolved Norflurazon, dissolved2,3 Prometryn, total3 Terbacil, dissolved3 Malathion, dissolved Ofloxacin, dissolved3 Propyzamide, dissolved2 Terbacil, total3 Malathion, total3 Ormetoprim, dissolved3 Propachlor ethanesulfonic acid, dissolved2,3 Terbufos oxygen analog sulfone, dissolved3 2-Methye-4-chlorophenoxyacetic acid, dissolved2,3 Oryzalin, dissolved2,3 Propachlor oxanilic acid, dissolved2,3 Terbufos, dissolved2,3 4-(2-Methye-4-chlorophenoxy) butric acid, dissolved2,3 Oxacillin, dissolved3 Propachlor, dissolved Terbuthylazine, dissolved Metalaxyl, dissolved3 Oxamyl, dissolved2,3 Propachlor, total3 Terbutryn, dissolved3 Methidathion, dissolved3 Oxolinic acid, dissolved2,3 Propanil, dissolved2,3 Tetracycline, dissolved2,3 Methiocarb, dissolved2,3 Oxytetracycline, dissolved3 Propargite, dissolved2,3 Thiobencarb, dissolved2,3 Methiocarb, total3 p,p’-dichlorodiphenyldichloro-ethane, total3 Propazine, dissolved Toxaphene, total3 Methomyl, dissolved2,3 p,p’-dichlorodiphenyldichloro-ethylene, dissolved Propazine, total trans-Chlordane, total3 Methomyl, total3 p,p’-dichlorodiphenyldichloro-ethylene, total3 Propham, dissolved2,3 Triallate, dissolved2,3 Methyl paraoxon, dissolved3 p,p’-dichlorodiphenyltrichloroethane, total3 Propham, total3 Tribuphos, total3 Methyl parathion, dissolved2 p,p’-Ethyl-dichlorodiphenyldichloroethane, total3 Propiconazole, dissolved3 Triclopyr, dissolved2,3 Methyl parathion, total3 p,p’-Methoxychlor, total3 Propoxur, dissolved2,3 Trifluralin, dissolved2 Metolachlor ethanesulfonic acid, dissolved2 Parathion, dissolved3 Propoxur, total3 Trifluralin, total3 Metolachlor oxanilic acid, dissolved2 Parathion, total3 Pyrene, total3 Trimethoprim, dissolved3 Metolachlor, dissolved Polychlorinated biphenyls, total3 Roxithromycin, dissolved Tylosin, dissolved3 Metolachlor, total Pebulate, dissolved2,3 Sarafloxacin, dissolved2,3 Vernolate, total3 Metribuzin, dissolved Pendimethalin, dissolved2 Siduron, dissolved3 Virginiamycin, dissolved3 Metribuzin, total3 Penicillin G, dissolved3 Silvex, dissolved3 Xylene (all isomers), total3 Metsulfuron, dissolved Penicillin V, dissolved3 Silvex, total3 1,1,1,2-Tetrachloroethane, total3 Minocycline, dissolved2,3 Pentachlorophenol, total3 Simazine, dissolved 1,1,1-Trichloroethane, total3 Mirex, total3 Phenanthrene, total3 Simazine, total 1,1,2,2-Tetrachloroethane, total3

Molinate, dissolved2 Phenol, total3 Simetryn, total3 1,1,2-Trichloro-1,2,2-trifluoroethane, total3Myclobutanil, dissolved3 Phorate oxygen analog, dissolved3 Sulfachlorpyridazine, dissolved2,3 1,1,2-Trichloroethane, total3N-(3,4-Dichlorophenyl)-N’-methylurea, dissolved3 Phorate, dissolved2,3 Sulfadiazine, dissolved3 1,1-Dichloroethane, total3N-(4-Chlorophenyl)-N’-methylurea, dissolved3 Phorate, total3 Sulfadimethoxine, dissolved2,3 1,1-Dichloroethene, total3Napropamide, dissolved2 Phosmet oxygen analog, dissolved3 Sulfamerazine, dissolved2,3 1,1-Dichloropropene, total3Neburon, dissolved2,3 Phosmet, dissolved3 Sulfamethazine, dissolved3 1,2,3-Trichlorobenzene, total3Nicosulfuron, dissolved Picloram, dissolved2,3 Sulfamethoxazole, dissolved2,3 1,2,3-Trichloropropane, total3
Appendix 73

Table A–2. Constituents analyzed in water samples for the Equus Beds Groundwater Recharge Project, 1995–2005.—Continued[<, less than; μm, micron; ELISA, enzyme-linked immunosorbent assay; m-TEC, membrane-thermotolerant Escherichia coli; MF, membrane filter]

Organic compounds (table A–6)—Continued

1,2,4-Trichlorobenzene, total3 Acrylonitrile, total3 Ethylbenzene, total3 trans-1,3-Dichloropropene, total3

1,2,4-Trimethylbenzene, total3 Benzene, total3 Hexachlorobutadiene, total3 Tribromomethane, total31,2-Dibromo-3-chloropropane, total3 Bromobenzene, total3 Hexachloroethane, total3 Trichloroethene, total31,2-Dibromoethane, total3 Bromochloromethane, total3 Isopropylbenzene, total3 Trichlorofluoromethane, total31,2-Dichlorobenzene, total3 Bromodichloromethane, total Naphthalene, total3 Trichloromethane, total

1,2-Dichloroethane, total Bromomethane, total3 n-Butylbenzene, total3 Vinyl chloride, total3

1,2-Dichloropropane, total3 Chlorobenzene, total3 n-Propylbenzene, total3 Dichlorvos, dissolved31,3,5-Trimethylbenzene, total3 Chloroethane, total3 sec-Butylbenzene, total31,3-Dichlorobenzene, total3 Chloromethane, total3 Styrene, total31,3-Dichloropropane, total3 cis-1,2-Dichloroethene, total3 Methyl tert-butyl ether, total

1,4-Dichlorobenzene, total3 cis-1,3-Dichloropropene, total3 tert-Butylbenzene, total3

2,2-Dichloropropane, total3 Dibromochloromethane, total Tetrachloroethene, total

2-Chlorotoluene, total3 Dibromomethane, total3 Tetrachloromethane, total3

4-Chlorotoluene, total3 Dichlorodifluoromethane, total3 Toluene, total34-Isopropyltoluene, total3 Dichloromethane, total3 trans-1,2-Dichloroethene, total3

Bacterial and viral indicators and triazine herbicides (table A–7)

Clostridium perfringens Enterococci Fecal coliform1 Atrazine

Coliphage, Escherichia coli, C13 Host Escherichia coli, modified m-TEC MF Method Fecal streptococci Triazine screen, ELISAColiphage, Escherichia coli, Famp Host Escherichia coli, m-TEC MF Method Total coliform1

Radionuclides (table A–8)

Alpha radioactivity, 2-sigma combined 

uncertainty, natural uranium curve, dissolved

Beta radioactivity, 2-sigma combined uncertainty, 

Cesium-137 curve, dissolved

Gross alpha radioactivity, natural uranium curve, 

dissolved

Gross beta radioactivity, Strontium-90/

Yttrium-90 curve, dissolved

Alpha radioactivity, 2-sigma combined 

uncertainty, Thorium-230 curve, dissolved

Beta radioactivity, 2-sigma combined uncertainty, 

Strontium-90/Yttrium-90 curve, dissolved

Gross beta radioactivity, Cesium-137 curve, 

dissolved

Uranium (natural), dissolved

Alpha radioactivity, Thorium-230 curve, dissolved

1 Key constituent analyzed in most samples.2 Constituent was analyzed using a 0.7-micron glass-fiber filter.3 Constituent concentration never exceeded the reporting level.
74 Water Quality in the Equus Beds Aquifer and the Little Arkansas River, South-Central Kansas Table A–3. Summary of physical properties and analysis of selected constituents in water samples collected as part of the Equus Beds Groundwater Recharge Project, 1995–2005. [mV, millivolts; NTU, nephelometric turbidity units; NephRatio, nephelometric ratio; NTRU, nephelometric turbidity ratio units; mg/L, milligrams per liter; μS/cm, microsiemens per centimeter at 25 degrees Celsius; CaCO3, calcium carbonate; --, not determined; MCL, Maximum Contaminant Level; SDWR, Secondary Drinking-Water Regulation; NA, not analyzed; <, less than; μm, micron; %, percent. The first set of numbers under each heading; for example 99–3,350, indicates the range in concentration. The number in parentheses () indicates the number of samples collected. The numbers below indicate the average followed by the median. Asterisk * is value estimated by using a log-probability regression to predict the values of data below the reporting level.] Data-collection site (fig. 6) Oxidation-reduction potential (mV) Turbidity (NTU) Turbidity, NephRatio (NTRU) Dissolved oxygen (mg/L) pH (standard units) Specific conductance (μS/cm) Temperature (degrees Celsius) Carbonate hardness (mg/L CaCO3

)

Hardness

(mg/L CaCO3

)

Drinking-water criteria -- 5 (MCL) 0.5–1.0 (SDWR) -- 6.5–8.5 (SDWR) -- -- -- --

Reporting level 1.0 0.1 0.1 0.1 0.1 1.0 -5.0 1.0 1.0

Surface-water monitoring sites (Little Arkansas River)

7143672 NA 0.3–1,780 (153) 3.3–1,150 (50) 2.5–16.2 (197) 6.2–8.5 (213) 99–3,550 (500) 0.2–29 (214) 27–520 (167) 27–580 (186)

 (near Halstead) NA 236; 85 232; 125 8.14; 7.7 7.58; 7.7 915; 864 15.5; 16.8 254; 280 267; 2907144100 NA 1.4–1,100 (170) 2.9–1,190 (69) 3.6–18.7 (210) 6–8.7 (227) 40–1,760 (2236) -0.2–32 (232) 16–420 (152) 16–420 (161) (near Sedgwick) NA 213; 75.5 211; 45 8.86; 8.35 7.67; 7.7 650; 657 17.1; 18 194; 190 200; 200

Diversion well site near Halstead

Diversion well 140–420 (41) 0.2–5.2 (111) 0.2–5.2 (111) 0–4.7 (353) 6.2–7.4 (397) 535–838 (397) 9.7–19.4 (394) 180–330 (141) 170–330 (152)

189; 170 1.88; 1.5 1.88; 1.5 0.477; 0.2 7.07; 7.1 771; 780 14.9; 14.8 267; 280 268; 280

EB-145-A1 90–190 (28) 0.6–970 (65) <0.1–31 (62) 0.1–2.2 (61) 6.2–7.1 (66) 407–1,390 (66) 10.5–18.9 (66) 150–430 (65) 150–440 (66)

130; 125 26.1; 10 1.32*; 0.1 0.321; 0.2 6.68; 6.7 1020; 1070 15.5; 15.7 317; 320 317; 325

EB-145-A2 80–170 (9) 1.1–21 (28) <0.1–0.9 (25) 0.1–0.7 (28) 6.4–7 (28) 951–1,220 (27) 14.3–17 (28) 280–430 (28) 280–430 (28)

126; 130 8.01; 6.7 0.266*; 0.2 0.268; 0.2 6.74; 6.75 1,060; 1,040 15.7; 15.6 340; 330 340; 330

EB-145-A3 120–190 (9) 0.2–110 (33) <0.1–1 (28) 0.1–1.1 (33) 6–7 (33) 990–1,240 (32) 15–16.2 (33) 340–450 (33) 350–450 (33)

154; 150 5.27; 2 0.241*; 0.1 0.239; 0.2 6.71; 6.7 1,140; 1,160 15.7; 15.7 398; 400 398; 400

EB-145-A4 120–190 (8) 0.1–4.1 (21) <0.1–0.5 (20) 0.1–1.1 (22) 6.7–7.3 (22) 528–1,060 (21) 14.8–15.8 (22) 170–430 (21) 170–430 (21)

166; 170 1.64; 1.5 0.132*; 0.1 0.218; 0.15 6.99; 7 779; 769 15.4; 15.4 282; 280 286; 280

EB-145-A5 130–380 (19) 0.3–7.4 (32) <0.1–0.6 (30) 0.1–0.7 (33) 6.6–7.2 (33) 641–865 (32) 14.9–16.2 (33) 240–370 (32) 260–370 (32)

207; 180 1.5; 1.05 0.183*; 0.1 0.242; 0.2 6.95; 7 768; 784 15.6; 15.6 318; 320 320; 320

EB-145-P-D5 110–270 (27) 0.2–4.5 (58) <0.1–3.3 (55) 0–0.7 (56) 6.2–7.3 (58) 449–908 (58) 15.2–16.5 (58) 140–320 (58) 140–320 (58)

147; 140 1.13; 0.8 0.320*; 0.1 0.2; 0.1 7.04; 7.1 651; 667 15.8; 15.8 211; 210 212; 215

Halstead recharge site

SMW-H4 260–670 (25) 0.1–1.1 (47) <0.1–3.3 (45) 0.1–7.8 (46) 5.3–7.2 (47) 473–841 (47) 14.7–17.3 (47) 150–310 (47) 150–310 (47)

496; 500 0.443; 0.4 0.409*; 0.3 4.68; 4.8 6.6; 6.6 694; 703 15.8; 15.7 253; 250 253; 250

SMW-H14 170–670 (22) 0.1–7.8 (46) 0.2–12 (42) 2.3–10.8 (46) 5.4–7.5 (46) 670–1,880 (46) 11–19.1 (46) 200–360 (46) 200–350 (46)

480; 525 1.04; 0.7 1.27; 0.8 6.01; 6.1 6.86; 6.85 896; 800 14.4; 14.3 279; 280 279; 280

DMW-H1 130–280 (26) 0.2–8.5 (46) 0–4.9 (44) 0–1.9 (44) 6.2–7.2 (46) 352–843 (46) 14.9–16.5 (46) 120–320 (46) 120–320 (46)

180; 180 1.68; 1.1 1.04; 0.6 0.236; 0.1 7; 7 746; 812 15.8; 15.8 268; 290 269; 290

DMW-H13 20–290 (22) 0.2–10 (46) <0.1–2.9 (42) 0–0.8 (46) 6–7.2 (46) 333–834 (46) 15.2–16.4 (46) 110–320 (46) 110–320 (46)

143; 135 3.1; 2.55 0.181*; 0.1 0.178; 0.1 7.01; 7.05 698; 804 15.7; 15.8 249; 280 249; 280

Sedgwick recharge site

Treated stream water NA 0.3–980 (48) 0–14 (9) 0.5–19.8 (196) 6.1–9.3 (229) 212–1,300 (230) 5.9–31 (215) 72–410 (48) 72–410 (48)

NA 42.3; 6.4 6; 5.7 10.3; 10.2 7.96; 8 617; 570 19.7; 20 193; 175 193; 175

SMW-S11 320–680 (31) 0.1–79 (52) 0.2–26 (51) 1.6–10.8 (51) 6.1–7.6 (52) 396–1,060 (52) 11.8–30 (52) 150–440 (52) 150–440 (52)

498; 520 3.28; 0.6 1.63; 0.6 6.03; 6.2 6.84; 6.8 643; 617 18.3; 16.2 242; 230 242; 230

SMW-S13 200–670 (32) 0.1–1260 (47) <0.1–8.5 (45) 4–8.4 (47) 6–7 (47) 467–772 (46) 12.5–22.5 (47) 150–360 (47) 150–350 (47)

526; 550 27.5; 0.5 0.658*; 0.4 5.94; 5.9 6.41; 6.4 611; 590 17.1; 16.6 232; 230 232; 230

DMW-S10 170–610 (22) <0.1–18 (40) <0.1–3.7 (40) 0.1–0.7 (36) 6.5–7.4 (40) 718–824 (40) 15.7–16.4 (40) 230–260 (40) 230–260 (40)

405; 430 1.34*; 0.4 0.635*; 0.3 0.2; 0.1 7.12; 7.2 792; 798 16.1; 16.1 245; 240 245; 240

DMW-S14 140–620 (23) <0.1–4 (36) <0.1–2.1 (34) 0.1–1 (32) 6.6–7.4 (36) 582–775 (36) 15.9–16.9 (36) 160–220 (36) 160–230 (36)

433; 480 0.419*; 0.2 0.333*; 0.1 0.234; 0.2 7.22; 7.3 639; 618 16.4; 16.3 181; 180 181; 180
Appendix 75

Table A–3. Summary of physical properties and analysis of selected constituents in water samples collected as part of the Equus Beds Groundwater Recharge Project, 1995–2005.—Continued[mV, millivolts; NTU, nephelometric turbidity units; NephRatio, nephelometric ratio; NTRU, nephelometric turbidity ratio units; mg/L, milligrams per liter; μS/cm, microsiemens per centimeter at 25 degrees Celsius; CaCO3, calcium carbonate; --, not determined; MCL, Maximum Contaminant Level; SDWR, Secondary Drinking-Water Regulation; NA, not analyzed; 

<, less than; μm, micron; %, percent. The first set of numbers under each heading; for example 99–3,350, indicates the range in concentration. The number in parentheses () indicates the number of samples collected. The numbers below indicate the average followed by the median. Asterisk * is value estimated by using a log-probability regression to predict the values of data below the reporting level.]

Data-collection 

site 

(fig. 6)

Alkalinity

(mg/L CaCO3

)

Dissolved solids

(mg/L)

Suspended solids

(mg/L)

Suspended sediment 

<63 μm

(% <63 μm)

Suspended 

sediment 

(mg/L)

Drinking-water criteria -- 500 (SDWR) -- -- --

Reporting level 2.0 1.0 4.0 0.1 0.5

Surface-water monitoring sites (Little Arkansas River)

7143672 3–310 (185) 85–1,960 (186) 4–2,240 (153) 16–100 (70) 18–2,950 (72)

 (near Halstead) 175; 205 550; 570 263; 90 91.6; 97 384; 223

7144100 18–292 (160) 50–759 (155) 4–1,820 (161) 41–100 (74) 4–1,970 (78) (near Sedgwick) 153; 148 368; 359 260; 116 95.1; 98 405; 243

Diversion well site near Halstead

Diversion well 101–280 (150) 292–552 (150) <4.00–167 (111) NA NA

258; 264 457; 479 --; <4.00 NA NA

EB-145-A1 166–389 (65) 348–942 (66) <4.00–17 (64) NA NA

282; 292 598; 605 5.29*; <4.00 NA NA

EB-145-A2 248–360 (28) 523–706 (28) <1.00–7 (28) NA NA

296; 296 612; 603 3.68*; <4.00 NA NA

EB-145-A3 312–420 (33) 605–768 (33) <4.00–5 (32) NA NA

360; 360 672; 670 --; <4.00 NA NA

EB-145-A4 219–327 (21) 307–680 (21) <4.00–<20.0 (21) NA NA

268; 253 464; 420 --; <4.00 NA NA

EB-145-A5 260–330 (32) 402–586 (32) <4.00–7 (32) NA NA

306; 309 494; 498 --; <4.00 NA NA

EB-145-P-D5 186–288 (58) 275–534 (58) <4.00–2 (58) NA NA

230; 238 389; 413 --; <4.00 NA NA

Halstead recharge site

SMW-H4 144–268 (47) 278–538 (47) <4.00–68 (47) NA NA

214; 214 424; 424 --; <4.00 NA NA

SMW-H14 186–298 (46) 172–1,060 (46) <4.00–24 (46) NA NA

239; 247 511; 481 --; <4.00 NA NA

DMW-H1 148–278 (46) 213–525 (46) <4.00–36 (46) NA NA

250; 266 453; 492 2.23*; <4.00 NA NA

DMW-H13 151–276 (46) 178–528 (46) <4.00–24 (46) NA NA

240; 264 422; 487 --; <4.00 NA NA

Sedgwick recharge site

Treated stream water 4–264 (48) 130–737 (48) <4.00–1,790 (226) NA NA

149; 136 344; 317 24.8*; 10 NA NA

SMW-S11 106–248 (52) 235–771 (52) <4.00–238 (52) NA NA

157; 154 404; 388 --; <4.00 NA NA

SMW-S13 108–184 (47) 223–506 (47) <4.00–4,010 (47) NA NA

134; 131 373; 366 --; <4.00 NA NA

DMW-S10 196–298 (40) 443–512 (40) <4.00–7 (40) NA NA

275; 276 472; 472 --; <4.00 NA NA

DMW-S14 148–272 (36) 188–467 (36) <4.00–<4.00 (36) NA NA

227; 224 383; 381 --; <4.00 NA NA
76 Water Quality in the Equus Beds Aquifer and the Little Arkansas River, South-Central Kansas Table A–3. Summary of physical properties and analysis of selected constituents in water samples collected as part of the Equus Beds Groundwater Recharge Project, 1995–2005.—Continued [mV, millivolts; NTU, nephelometric turbidity units; NephRatio, nephelometric ratio; NTRU, nephelometric turbidity ratio units; mg/L, milligrams per liter; μS/cm, microsiemens per centimeter at 25 degrees Celsius; CaCO3, calcium carbonate; --, not determined; MCL, Maximum Contaminant Level; SDWR, Secondary Drinking-Water Regulation; NA, not analyzed; <, less than; μm, micron; %, percent. The first set of numbers under each heading; for example 99–3,350, indicates the range in concentration. The number in parentheses () indicates the number of samples collected. The numbers below indicate the average followed by the median. Asterisk * is value estimated by using a log-probability regression to predict the values of data below the reporting level.] Data-collection site (fig. 6) Oxidation-reduction potential (mV) Turbidity (NTU) Turbidity, NephRatio (NTRU) Dissolved oxygen (mg/L) pH (standard units) Specific conductance (μS/cm) Temperature (degrees Celsius) Carbonate hardness (mg/L CaCO3

)

Hardness

(mg/L CaCO3

)

Drinking-water criteria -- 5 (MCL) 0.5–1.0 (SDWR) -- 6.5–8.5 (SDWR) -- -- -- --

Reporting level 1.0 0.1 0.1 0.1 0.1 1.0 -5.0 1.0 1.0

Background wells

EB-142-A3 NA 0.2–0.2 (3) 0.2–0.6 (3) 0.1–0.2 (3) 6.6–6.8 (3) 618–638 (3) 15.8–16.8 (3) 220–240 (3) 220–240 (3)

NA --; -- --; -- --; -- --; -- --; -- --; -- --; -- --; --

Sedgwick well 110–350 (24) 0.3–160 (45) <0.1–4.4 (44) 0.1–1.2 (45) 6.1–7 (46) 504–686 (46) 14.9–16.6 (46) 210–280 (45) 220–280 (45)

203; 195 5.26; 1.3 0.771*; 0.4 0.251; 0.2 6.78; 6.8 640; 637 15.7; 15.8 251; 260 251; 260

City well-Sedgwick NA --–2 (1) --–0.4 (1) --–0.5 (1) --–7 (1) --–800 (1) --–14.9 (1) --–290 (1) --–280 (1)

NA --; -- --; -- --; -- --; -- --; -- --; -- --; -- --; --

TH-02-95 100–270 (24) 0.6–13 (25) <0.1–3.2 (26) 0–1.3 (26) 6.7–7.2 (26) 631–732 (26) 14.8–16.1 (26) 260–300 (25) 270–300 (25)

151; 140 4.85; 4.8 0.235*; <0.1 0.285; 0.2 7.01; 7 679; 687 15.5; 15.5 286; 290 287; 290

TH-06-95 90–260 (25) 1–37 (27) 0.1–7.5 (28) 0–0.7 (28) 6.5–7.1 (28) 434–602 (29) 15.2–29 (28) 210–420 (27) 230–260 (27)

160; 160 3.84; 2.4 1.45; 0.55 0.243; 0.2 6.84; 6.85 532; 530 16.2; 15.8 250; 250 244; 250

TH-10-95 90–200 (26) 0.4–3.5 (27) <0.1–3.7 (28) 0–0.6 (28) 6.9–7.4 (28) 315–419 (28) 15–16.1 (28) 130–190 (27) 140–190 (27)

125; 120 1.91; 1.9 0.610*; 0.3 0.196; 0.15 7.19; 7.2 363; 362 15.6; 15.6 153; 150 154; 150

TH-12-95 NA --–0.2 (1) 0.5–0.5 (2) 0.1–0.1 (2) 6.6–6.8 (2) 685–834 (2) 15.3–15.8 (2) --–310 (1) --–340 (1)

NA --; -- --; -- --; -- --; -- --; -- --; -- --; -- --; --

TH-08-A1 NA 0.2–48 (7) 0.2–26 (5) 0.1–0.5 (7) 6.6–7 (7) 625–740 (7) 15–16.9 (7) 190–240 (7) 200–230 (7)

NA 7.64; 0.4 --; -- 0.243; 0.2 6.83; 6.9 683; 663 15.8; 15.6 216; 220 217; 220

TH-08-A2 --–310 (1) 0.1–2 (10) <0.1–0.5 (10) 0–0.8 (10) 6.2–7.2 (10) 680–906 (10) 14.7–16.4 (10) 230–360 (10) 230–360 (10)

--; -- 0.42; 0.2 0.152*; 0.1 0.28; 0.2 6.97; 7.1 768; 762 15.5; 15.5 285; 290 285; 290

TH-08-A3 30–290 (20) 0.5–4.7 (23) 0.2–8.7 (23) 0.1–1.2 (24) 6.6–7.2 (24) 583–817 (24) 15.1–17.4 (24) 180–240 (23) 180–240 (23)

163; 155 2.37; 2.4 1.7; 0.8 0.275; 0.2 7.03; 7.1 632; 608 16.1; 16.2 193; 190 193; 190

TH-08-A4 --–220 (1) --–2 (1) --–<0.1 (1) --–0.1 (1) --–7 (1) --–567 (1) --–16.6 (1) --–180 (1) --–180 (1)

--; -- --; -- --; -- --; -- --; -- --; -- --; -- --; -- --; --

TH-08-A5 290–560 (12) 0.1–0.8 (12) <0.1–4 (12) 0–2 (13) 6.6–7 (13) 483–682 (13) 15–16.3 (13) 190–260 (12) 190–260 (12)

420; 455 0.367; 0.35 0.529*; 0.1 0.438; 0.2 6.82; 6.8 613; 653 15.7; 15.8 214; 210 214; 210

Alta Mills 200–600 (23) 0.9–3.4 (23) 0.4–7.2 (23) 0.2–1.1 (23) 6.7–7.1 (23) 714–820 (23) 15–15.6 (23) 320–360 (23) 320–360 (23)

467; 480 2; 1.9 2.66; 2.2 0.587; 0.6 6.91; 6.9 778; 785 15.2; 15.2 338; 340 338; 340

Aquifer storage and recovery prototype wells

DW-TW-01 160–530 (7) <0.1–1.1 (7) 0.4–13 (7) 0.1–0.3 (7) 7–7.5 (7) 361–405 (7) 15.6–16.4 (7) 130–140 (7) 130–140 (7)

377; 400 0.279*; 0.2 3.39; 2 0.129; 0.1 7.31; 7.4 384; 382 16; 15.8 131; 130 131; 130

DW-TW-02 140–500 (7) 0.2–0.5 (7) 0.1–0.9 (7) 0.1–0.2 (7) 7–7.5 (7) 364–387 (7) 15.5–16.2 (7) 120–140 (7) 120–140 (7)

344; 320 0.286; 0.3 0.429; 0.4 0.114; 0.1 7.34; 7.5 373; 370 15.8; 15.7 131; 130 131; 130

DW-TW-03 160–480 (8) <0.1–0.4 (7) <0.1–0.3 (8) 0.1–0.2 (8) 7.1–7.6 (8) 358–387 (8) 15.5–16.3 (8) 130–140 (7) 130–140 (7)

269; 230 0.125*; 0.1 --; <0.1 0.113; 0.1 7.39; 7.4 372; 369 15.8; 15.9 131; 130 131; 130

DW-TW-04 140–480 (7) <0.1–0.6 (7) <0.1–2.3 (7) 0.1–0.2 (7) 7.1–7.5 (7) 361–390 (7) 15.4–16.1 (7) 130–140 (7) 130–140 (7)

230; 190 0.199*; 0.2 0.662*; 0.4 0.114; 0.1 7.41; 7.5 369; 367 15.7; 15.6 133; 130 133; 130

DW-TW-05 110–510 (8) <0.1–0.2 (7) <0.1–1 (8) 0.1–0.1 (8) 7.1–7.5 (8) 346–394 (8) 15.6–16.4 (8) 130–140 (7) 130–140 (7)

259; 240 0.123*; 0.1 0.374*; 0.1 0.1; 0.1 7.38; 7.4 376; 379 15.9; 15.9 134; 130 137; 140

DW-TW-06 160–300 (8) <0.1–0.1 (7) <0.1–2.7 (8) 0.1–0.1 (8) 6.9–7.5 (8) 355–386 (8) 15.2–15.8 (8) 130–150 (7) 130–150 (7)

235; 235 0.100*; 0.1 0.498*; 0.2 0.1; 0.1 7.38; 7.45 364; 362 15.7; 15.8 134; 130 134; 130

DW-TW-07 110–260 (8) 0.1–1.5 (7) <0.1–2.5 (8) 0.1–0.2 (8) 6.9–7.5 (8) 370–640 (8) 15.4–16 (8) 140–240 (7) 140–240 (7)

193; 195 0.329; 0.1 0.465*; 0.1 0.113; 0.1 7.38; 7.45 417; 379 15.8; 15.9 159; 140 160; 150

DW-TW-08 190–340 (5) 0.1–0.2 (4) <2–0.2 (6) 0.1–0.1 (5) 7.4–7.5 (5) 377–388 (5) 15.6–16 (5) 140–140 (4) 140–140 (4)

--; -- --; -- 0.179*; 0.2 --; -- --; -- --; -- --; -- --; -- --; --

DW-TW-09 290–370 (5) 0.1–0.3 (4) <2–1.9 (6) 0.1–0.1 (5) 7.4–7.5 (5) 365–382 (5) 15.6–16 (5) 130–140 (4) 130–140 (4)

--; -- --; -- 0.665*; 0.2 --; -- --; -- --; -- --; -- --; -- --; --

RRW-01 180–500 (8) 0.5–8.3 (7) 0.8–5.9 (8) 0.1–0.3 (8) 6.5–7 (8) 285–307 (8) 15–16.7 (8) 110–140 (7) 110–140 (7)

304; 275 3.64; 3.4 2.8; 2.3 0.138; 0.1 6.91; 7 296; 300 15.7; 15.7 119; 110 119; 110

RRW-02 120–430 (8) 0.5–9.5 (7) 0.9–4.1 (8) 0.1–0.1 (7) 7.4–7.7 (8) 382–402 (8) 16.3–17.4 (8) 130–140 (7) 130–140 (7)

230; 200 3.2; 1 1.8; 1.3 0.1; 0.1 7.51; 7.5 391; 389 16.7; 16.7 137; 140 137; 140

RRW-03 40–320 (5) 0.1–1.9 (5) 0.1–0.9 (5) 0.1–0.3 (5) 6.9–7.2 (5) 420–470 (5) 16–17.3 (5) 130–160 (5) 140–160 (5)

--; -- --; -- --; -- --; -- --; -- --; -- --; -- --; -- --; --
Appendix 77

Table A–3. Summary of physical properties and analysis of selected constituents in water samples collected as part of the Equus Beds 

Groundwater Recharge Project, 1995–2005.—Continued

[mV, millivolts; NTU, nephelometric turbidity units; NephRatio, nephelometric ratio; NTRU, nephelometric turbidity ratio units; mg/L, milligrams per liter; μS/cm, microsiemens per centimeter at 25 degrees Celsius; CaCO3, 

calcium carbonate; --, not determined; MCL, Maximum Contaminant Level; SDWR, Secondary Drinking-Water Regulation; NA, not analyzed; <, less than; μm, micron; %, percent. The first set of numbers under each heading; for example 99–3,350, indicates the range in concentration. The number in parentheses () indicates the number of samples collected. The numbers below indicate the average followed by the median. Asterisk * is value estimated by using a log-probability regression to predict the values of data below the reporting level.]

Data-collection 

site 

(fig. 6)

Alkalinity

(mg/L CaCO3)

Dissolved solids

(mg/L)

Suspended solids

(mg/L)

Suspended sediment 

<63 μm

(% <63 μm)

Suspended 

sediment 

(mg/L)

Drinking-water criteria -- 500 (SDWR) -- -- --

Reporting level 2.0 1.0 4.0 0.1 0.5

Background wells

EB-142-A3 198–200 (3) 381–393 (3) <4.00–<4.00 (3) NA NA

--; -- --; -- --; -- NA NA

Sedgwick well 182–280 (45) 369–454 (45) <4.00–11 (45) NA NA

204; 204 407; 406 1.95*; <4.00 NA NA

City well-Sedgwick --–285 (1) --–479 (1) --–<4.00 (1) NA NA

--; -- --; -- --; -- NA NA

TH-02-95 280–316 (25) 386–503 (25) <4.00–2 (25) NA NA

292; 290 423; 421 --; <4.00 NA NA

TH-06-95 206–236 (27) 330–440 (27) <4.00–53 (27) NA NA

223; 224 350; 348 5.22*; <4.00 NA NA

TH-10-95 174–318 (27) 197–513 (27) <4.00–2 (27) NA NA

190; 184 237; 226 --; <4.00 NA NA

TH-12-95 --–232 (1) --–560 (1) --–<4.00 (1) NA NA

--; -- --; -- --; -- NA NA

TH-08-A1 230–246 (7) 332–449 (7) <4.00–101 (7) NA NA

241; 242 397; 389 --; <4.00 NA NA

TH-08-A2 260–292 (10) 389–553 (10) <4.00–<4.00 (10) NA NA

280; 282 458; 455 --; <4.00 NA NA

TH-08-A3 236–288 (23) 339–479 (23) <4.00–13 (23) NA NA

250; 246 388; 374 3.12*; <4.00 NA NA

TH-08-A4 --–233 (1) --–345 (1) --–<4.00 (1) NA NA

--; -- --; -- --; -- NA NA

TH-08-A5 206–273 (12) 301–430 (12) <4.00–<4.00 (12) NA NA

251; 265 378; 400 --; <4.00 NA NA

Alta Mills 180–340 (23) 211–560 (23) <4.00–5 (23) NA NA

308; 316 486; 498 --; <4.00 NA NA

Aquifer storage and recovery prototype wells

DW-TW-01 169–180 (7) 225–244 (7) <4.00–<4.00 (7) NA NA

177; 180 232; 231 --; <4.00 NA NA

DW-TW-02 172–178 (7) 222–249 (7) <4.00–<4.00 (7) NA NA

175; 175 231; 229 --; <4.00 NA NA

DW-TW-03 170–180 (7) 209–232 (7) <4.00–<4.00 (7) NA NA

174; 174 223; 228 --; <4.00 NA NA

DW-TW-04 168–184 (7) 221–238 (7) <4.00–<4.00 (7) NA NA

176; 178 231; 232 --; <4.00 NA NA

DW-TW-05 176–184 (7) 211–245 (7) <4.00–<4.00 (7) NA NA

179; 178 233; 237 --; <4.00 NA NA

DW-TW-06 168–178 (7) 222–239 (7) <4.00–<4.00 (7) NA NA

174; 176 228; 227 --; <4.00 NA NA

DW-TW-07 170–178 (7) 148–389 (7) <4.00–<4.00 (7) NA NA

175; 178 248; 241 --; <4.00 NA NA

DW-TW-08 174–187 (4) 225–238 (4) <4.00–<4.00 (4) NA NA

--; -- --; -- --; -- NA NA

DW-TW-09 177–189 (4) 210–238 (4) <4.00–<4.00 (4) NA NA

--; -- --; -- --; -- NA NA

RRW-01 132–155 (7) 146–195 (7) <4.00–12 (7) NA NA

140; 138 181; 189 --; <4.00 NA NA

RRW-02 169–192 (7) 232–268 (7) <4.00–5 (7) NA NA

178; 177 246; 242 --; <4.00 NA NA

RRW-03 127–144 (5) 252–271 (5) <4.00–<4.00 (5) NA NA

--; -- --; -- --; -- NA NA
78 Water Quality in the Equus Beds Aquifer and the Little Arkansas River, South-Central Kansas Table A–3. Summary of physical properties and analysis of selected constituents in water samples collected as part of the Equus Beds Groundwater Recharge Project, 1995–2005.—Continued [mV, millivolts; NTU, nephelometric turbidity units; NephRatio, nephelometric ratio; NTRU, nephelometric turbidity ratio units; mg/L, milligrams per liter; μS/cm, microsiemens per centimeter at 25 degrees Celsius; CaCO3, calcium carbonate; --, not determined; MCL, Maxi- mum Contaminant Level; SDWR, Secondary Drinking-Water Regulation; NA, not analyzed; <, less than; μm, micron; %, percent. The first set of numbers under each heading; for example 99–3,350, indicates the range in concentration. The number in parentheses () indicates the number of samples collected. The numbers below indicate the average followed by the median. Asterisk * is value estimated by using a log-probability regression to predict the values of data below the reporting level.] Data-collection site (fig. 6) Oxidation-reduction potential (mV) Turbidity (NTU) Turbidity, NephRatio (NTRU) Dissolved oxygen (mg/L) pH (standard units) Specific conductance (μS/cm) Temperature (degrees Celsius) Carbonate hardness (mg/L CaCO3

)

Hardness

(mg/L CaCO3

)

Drinking-water criteria -- 5 (MCL) 0.5–1.0 (SDWR) -- 6.5–8.5 (SDWR) -- -- -- --

Reporting level 1.0 0.1 0.1 0.1 0.1 1.0 -5.0 1.0 1.0

Shallow index wells

IW-01A 250–600 (8) 0.8–3.4 (7) 1.2–3.6 (8) 0.1–0.6 (8) 5.8–6.1 (8) 108–168 (8) 14.8–15 (8) 26–44 (7) 26–44 (7)

466; 465 2.29; 2.7 1.86; 1.65 0.25; 0.2 5.94; 5.95 143; 144 14.9; 14.8 36.9; 37 36.9; 37

IW-02A 420–700 (8) 0.4–5 (7) <0.1–9.3 (8) 0.9–1.3 (8) 5.8–6.2 (8) 168–200 (8) 15–17.9 (8) 40–53 (7) 40–53 (7)

513; 495 1.33; 0.7 2.03*; 1 0.987; 0.95 5.98; 6 179; 177 15.7; 15.4 43.9; 42 44.1; 43

IW-03A 140–310 (8) 0.7–2.9 (7) <0.1–4.1 (8) 0.1–0.5 (8) 6.5–6.7 (8) 461–547 (8) 14.6–16.7 (8) 130–180 (7) 130–180 (7)

200; 190 1.53; 1.4 1.10*; 0.1 0.237; 0.2 6.59; 6.55 512; 514 15.2; 15.2 156; 150 156; 150

IW-04A 30–580 (9) 2.3–110 (7) 0.6–21 (10) 0.2–3.5 (9) 6.1–7.1 (9) 506–638 (9) 15.3–18.9 (9) 93–150 (7) 93–150 (7)

357; 400 31.4; 6.7 5.36; 3.7 2.1; 2.2 6.36; 6.3 563; 548 17.2; 17.2 119; 110 119; 110

IW-05A 270–600 (7) 1.5–20 (7) 3.3–26 (7) 0.7–1.8 (7) 6–6.3 (7) 368–423 (7) 14.9–16.2 (7) 110–140 (7) 110–140 (7)

454; 530 8.3; 4.9 8.86; 5.2 1.16; 1.1 6.17; 6.2 396; 384 15.7; 15.8 124; 120 124; 120

IW-06A 360–630 (10) 0.1–1.2 (7) <2–1.9 (12) 4.5–6 (10) 6–6.3 (10) 553–645 (10) 14.9–16.7 (10) 190–220 (7) 190–220 (8)

522; 535 0.414; 0.3 0.645*; 0.6 5.27; 5.25 6.17; 6.2 603; 598 15.7; 15.9 199; 200 199; 195

IW-07A 200–400 (8) 0.4–3.4 (7) 0.2–6.9 (8) 0.2–0.6 (8) 7–7.2 (8) 350–363 (8) 14.9–17.1 (8) 120–130 (7) 130–130 (7)

255; 200 1.21; 1 1.4; 0.6 0.312; 0.2 7.14; 7.15 358; 359 15.8; 16.1 129; 130 130; 130

IW-08A 270–560 (8) 1.2–6.1 (7) 1.1–11 (8) 0.3–6.2 (8) 6.7–6.8 (8) 1,420–1,680 (8) 14.6–15.6 (8) 490–550 (7) 490–550 (7)

381; 310 3.14; 2.6 3.31; 1.9 1.36; 0.65 6.76; 6.8 1,540; 1,550 15; 15 529; 540 529; 540

IW-09A 320–600 (8) 0.2–1 (7) <0.1–2.4 (8) 0.3–1.5 (8) 6.9–7 (8) 546–595 (8) 15.2–16.1 (8) 210–230 (7) 210–230 (7)

460; 470 0.4; 0.3 0.544*; 0.3 0.875; 0.85 6.98; 7 569; 567 15.7; 15.7 216; 210 217; 220

IW-10A 420–600 (7) 0.3–2.2 (7) <0.1–2.6 (7) 2.5–3.8 (7) 6.3–6.6 (7) 409–529 (7) 14.6–16.1 (7) 140–180 (7) 150–180 (7)

489; 470 0.957; 1 1.23*; 1.3 3.27; 3.4 6.43; 6.4 479; 482 15.4; 15.2 160; 160 161; 160

IW-11A 100–190 (8) 1.5–6.3 (7) <0.1–4.1 (8) 0.1–0.4 (8) 7–7.5 (8) 380–483 (8) 14.4–16.4 (8) 120–170 (7) 120–170 (7)

121; 115 4.1; 4.6 --; <0.1 0.212; 0.2 7.28; 7.25 426; 420 15.8; 16 136; 130 137; 130

IW-12A 250–590 (9) 0.3–1.7 (8) <0.1–2.3 (10) 0.6–1.9 (9) 6.5–6.8 (9) 477–819 (9) 15.8–16.6 (9) 190–310 (8) 190–310 (9)

376; 320 0.938; 1.1 0.879*; 0.5 0.911; 0.8 6.67; 6.7 612; 600 16.2; 16.3 146; 250 240; 250

IW-13A 140–190 (8) 1.4–5.2 (7) <0.1–18 (9) 0.1–0.3 (8) 6.6–7 (8) 1,160–1,420 (8) 14.5–16.3 (8) 390–440 (7) 390–440 (8)

158; 150 3.4; 3.5 3.44*; 1.2 0.213; 0.2 6.85; 6.9 1,270; 1,250 15.4; 15.5 399; 390 398; 390

IW-14A 210–470 (8) 0.2–3.9 (8) 0.4–11 (8) 0.1–0.3 (8) 5.6–6.6 (8) 661–1,370 (8) 15.3–16.2 (8) 140–440 (8) 140–440 (8)

298; 270 1.06; 0.7 4.29; 1.85 0.2; 0.2 6.01; 5.95 852; 773 15.6; 15.5 233; 210 233; 210

IW-15A 90–160 (8) 1.9–5.7 (7) <0.1–70 (9) 0.1–0.3 (8) 6.7–6.9 (8) 1,290–1,480 (8) 14.5–16.7 (8) 560–680 (7) 560–680 (7)

129; 130 3.64; 3.5 8.53*; 0.5 0.162; 0.15 6.81; 6.8 1,360; 1,370 15.5; 15.6 599; 590 600; 600

IW-16A 100–180 (9) 2–3.7 (7) <0.1–0.8 (9) 0.1–0.4 (9) 6.3–6.8 (9) 783–935 (9) 14.7–16.2 (9) 350–390 (7) 350–390 (7)

149; 150 2.74; 2.8 0.387*; 0.3 0.178; 0.2 6.59; 6.6 855; 843 15.5; 15.5 364; 360 364; 360

IW-17A 120–320 (8) 1–13 (7) <0.1–1.4 (7) 0.1–0.6 (8) 6.7–7 (9) 863–917 (9) 15.4–17.5 (9) 310–340 (7) 310–340 (7)

180; 160 3.81; 2 0.847*; 0.9 0.262; 0.2 6.86; 6.9 889; 894 16.2; 16.3 324; 320 324; 320

IW-18A 180–510 (8) 0.6–6.6 (7) <0.1–8.2 (8) 0.3–1.4 (9) 6.8–7.2 (9) 1,190–1,320 (9) 13.1–15.2 (9) 420–480 (7) 420–480 (7)

311; 305 2.34; 2.4 2.97*; 0.6 0.856; 0.8 6.98; 7 1250; 1250 14.3; 14.3 440; 430 440; 430

IW-19A 140–210 (8) 2–6.5 (7) <0.1–1.1 (8) 0.1–0.4 (8) 6.6–6.9 (8) 1,440–1,730 (8) 14.7–15.7 (8) 500–590 (7) 500–590 (7)

163; 155 4.5; 4.4 --; <0.1 0.225; 0.2 6.79; 6.8 1610; 1620 15.3; 15.3 550; 550 550; 550

IW-20A 140–200 (9) 3.5–49 (7) 1–8.8 (9) 0.1–0.3 (9) 6.2–6.4 (9) 1,680–1,900 (9) 14.3–15.6 (9) 610–720 (7) 610–720 (7)

169; 160 13.3; 5.9 5.14; 6.2 0.211; 0.3 6.31; 6.3 1,840; 1,870 15.1; 15.3 667; 670 667; 670

IW-21A 120–160 (8) 2–9.2 (7) <0.1–3.1 (8) 0.1–0.5 (8) 6.6–6.7 (8) 923–1,110 (8) 14.6–16.1 (8) 360–470 (7) 360–470 (7)

139; 140 3.43; 2.3 0.965*; 0.4 0.213; 0.15 6.68; 6.7 1,000; 952 15.4; 15.3 400; 380 400; 380
Appendix 79

Table A–3. Summary of physical properties and analysis of selected constituents in water samples collected as part of the Equus

Beds Groundwater Recharge Project, 1995–2005.—Continued

[mV, millivolts; NTU, nephelometric turbidity units; NephRatio, nephelometric ratio; NTRU, nephelometric turbidity ratio units; mg/L, milligrams per liter; μS/cm, microsiemens per centimeter at 25 degrees Celsius; CaCO3, calcium carbonate; --, not determined; MCL, Maximum Contaminant Level; SDWR, Secondary Drinking-Water Regulation; NA, not analyzed; <, less than; μm, micron; %, percent. The first set of 

numbers under each heading; for example 99–3,350, indicates the range in concentration. The number in parentheses () indicates the number of samples collected. The numbers below indicate the average followed by the median. Asterisk * is value estimated by using a log-probability regression to predict the values of data below the reporting level.]

Data-collection 

site 

(fig. 6)

Alkalinity

(mg/L CaCO3)

Dissolved solids

(mg/L)

Suspended solids

(mg/L)

Suspended sediment 

<63 μm

(% <63 μm)

Suspended 

sediment 

(mg/L)

Drinking-water criteria -- 500 (SDWR) -- -- --Reporting level 2.0 1.0 4.0 0.1 0.5

Shallow index wells

IW-01A 32–57 (7) 100–114 (7) <4.00–4 (7) NA NA

42.1; 41 107; 106 --; <4.00 NA NA

IW-02A 28–39 (7) 98–144 (7) <4.00–<4.00 (7) NA NA

32.6; 31 122; 123 --; <4.00 NA NA

IW-03A 202–228 (7) 283–342 (7) <4.00–5 (7) NA NA

217; 215 315; 315 --; <4.00 NA NA

IW-04A 132–220 (7) 300–373 (7) <4.00–46 (7) NA NA

181; 180 327; 315 --; <4.00 NA NA

IW-05A 76–90 (7) 211–282 (7) <4.00–16 (7) NA NA

82.7; 82 240; 230 --; 9 NA NA

IW-06A 80–100 (7) 351–429 (8) <4.00–<4.00 (7) NA NA

90.3; 88 396; 390 --; <4.00 NA NA

IW-07A 164–170 (7) 202–221 (7) <4.00–<4.00 (7) NA NA

167; 167 214; 213 --; <4.00 NA NA

IW-08A 228–278 (7) 935–1,100 (7) <4.00–10 (7) NA NA

255; 256 1,050; 1,060 --; <4.00 NA NA

IW-09A 110–144 (7) 362–392 (7) <4.00–4 (7) NA NA

128; 126 375; 374 --; <4.00 NA NA

IW-10A 87–94 (7) 232–320 (7) <4.00–44 (7) NA NA

91.1; 91 286; 300 --; <4.00 NA NA

IW-11A 186–254 (7) 220–287 (7) <4.00–<4.00 (7) NA NA

210; 208 249; 255 --; <4.00 NA NA

IW-12A 184–289 (8) 295–527 (9) <4.00–<4.00 (8) NA NA

239; 236 391; 356 --; <4.00 NA NA

IW-13A 272–294 (7) 724–881 (8) <4.00–8 (7) NA NA

279; 278 784; 785 5.59*; 6 NA NA

IW-14A 61–220 (8) 406–875 (8) <4.00–7 (8) NA NA

127; 120 542; 495 --; <4.00 NA NA

IW-15A 208–235 (7) 887–1,060 (7) <4.00–11 (7) NA NA

219; 220 969; 976 7.08*; 7 NA NA

IW-16A 137–166 (7) 529–657 (7) <4.00–12 (7) NA NA

148; 146 601; 597 5.20*; 4 NA NA

IW-17A 328–359 (7) 554–604 (7) <4.00–6 (7) NA NA

345; 346 582; 581 --; <4.00 NA NA

IW-18A 295–308 (7) 725–812 (7) <4.00–6 (7) NA NA

300; 300 771; 774 --; <4.00 NA NA

IW-19A 302–367 (7) 943–1,160 (7) <4.00–5 (7) NA NA

343; 347 1,070; 1,050 4.19*; 4 NA NA

IW-20A 169–180 (7) 1,280–1,520 (7) 5–18 (7) NA NA

174; 172 1,420; 1,430 10; 9 NA NA

IW-21A 169–232 (7) 611–799 (7) 5–9 (7) NA NA

193; 188 679; 648 6.71; 6 NA NA
80 Water Quality in the Equus Beds Aquifer and the Little Arkansas River, South-Central Kansas Table A–3. Summary of physical properties and analysis of selected constituents in water samples collected as part of the Equus Beds Groundwater Recharge Project, 1995–2005.—Continued [mV, millivolts; NTU, nephelometric turbidity units; NephRatio, nephelometric ratio; NTRU, nephelometric turbidity ratio units; mg/L, milligrams per liter; μS/cm, microsiemens per centimeter at 25 degrees Celsius; CaCO3, calcium carbonate; --, not determined; MCL, Maxi- mum Contaminant Level; SDWR, Secondary Drinking-Water Regulation; NA, not analyzed; <, less than; μm, micron; %, percent. The first set of numbers under each heading; for example 99–3,350, indicates the range in concentration. The number in parentheses () indicates the number of samples collected. The numbers below indicate the average followed by the median. Asterisk * is value estimated by using a log-probability regression to predict the values of data below the reporting level.] Data-collection site (fig. 6) Oxidation-reduction potential (mV) Turbidity (NTU) Turbidity, NephRatio (NTRU) Dissolved oxygen (mg/L) pH (standard units) Specific conductance (μS/cm) Temperature (degrees Celsius) Carbonate hardness (mg/L CaCO3

)

Hardness

(mg/L CaCO3

)

Drinking-water criteria -- 5 (MCL) 0.5–1.0 (SDWR) -- 6.5–8.5 (SDWR) -- -- -- --

Reporting level 1.0 0.1 0.1 0.1 0.1 1.0 -5.0 1.0 1.0

Shallow index wells—Continued

IW-22A 210–400 (8) 0.1–0.7 (7) <0.1–3 (9) 0.1–0.5 (8) 6.5–7 (8) 818–943 (8) 15.3–16 (8) 350–410 (7) 340–410 (8)

274; 240 0.3; 0.2 0.815*; 0.3 0.275; 0.2 6.85; 6.9 886; 884 15.7; 15.7 374; 370 371; 365

IW-23A 100–190 (8) 2.1–12 (7) <0.1–0.5 (8) 0.1–1.5 (7) 6.9–7.3 (9) 544–751 (9) 15–16.9 (9) 190–240 (7) 190–240 (7)

129; 115 6.01; 4.3 0.369*; 0.3 0.4; 0.3 7.12; 7.1 679; 701 16; 16.2 221; 220 221; 220

IW-24A 240–650 (10) 0.1–0.3 (7) <0.1–1.4 (10) 1.2–2.5 (10) 6.6–7.1 (10) 847–950 (10) 15.2–16.1 (10) 320–350 (7) 310–350 (8)

516; 550 0.2; 0.2 --; <0.1 1.89; 1.9 6.9; 7 922; 931 15.7; 15.8 329; 320 328; 320

IW-25A 320–660 (8) 0.1–0.4 (7) <0.1–2.9 (8) 0.1–2.2 (8) 6.6–7.2 (8) 852–958 (8) 15.1–15.6 (8) 290–330 (7) 290–330 (7)

506; 525 0.243; 0.2 0.539*; 0.2 0.6; 0.3 6.96; 7.05 878; 869 15.3; 15.4 300; 290 300; 290

IW-26A 360–550 (8) 0.2–1 (7) <0.1–4.8 (8) 0.4–3.8 (8) 7.1–7.2 (8) 620–725 (8) 15.4–15.9 (8) 250–320 (7) 250–320 (7)

465; 470 0.571; 0.5 1.19*; 0.5 1.75; 1.35 7.16; 7.2 682; 685 15.7; 15.7 281; 280 283; 280

IW-27A 420–580 (8) 0.2–0.7 (7) <0.1–3.8 (8) 0.7–1.4 (8) 6.5–7 (8) 800–839 (8) 15.2–15.9 (8) 360–390 (7) 360–390 (7)

503; 505 0.343; 0.3 --; <0.1 1.01; 0.95 6.85; 6.9 819; 817 15.6; 15.6 377; 380 377; 380

IW-28A 330–540 (8) 0.1–14 (7) <0.1–3.1 (8) 0.5–1.7 (7) 6–6.9 (8) 848–949 (8) 15.2–16.5 (8) 370–420 (7) 370–420 (7)

440; 430 2.13; 0.1 0.569*; 0.3 0.814; 0.7 6.61; 6.65 905; 914 15.8; 15.9 396; 400 397; 400

IW-29A 100–210 (8) 4.1–16 (8) <0.1–42 (10) 0.1–0.3 (7) 6.8–7 (8) 1,220–1,690 (8) 15.3–16.8 (8) 390–550 (8) 390–550 (10)

141; 135 10.2; 11 8.64*; 0.3 0.157; 0.1 6.89; 6.9 1,450; 1,400 16; 16 480; 465 472; 460

IW-30A 370–610 (8) 0.2–0.9 (7) <0.1–5.3 (11) 4.2–6.5 (8) 6.4–6.9 (8) 1,060–1,260 (8) 14.3–16.2 (8) 250–340 (7) 260–340 (9)

539; 565 0.5; 0.5 1.23*; 0.5 5.68; 5.8 6.7; 6.75 1,150; 1,150 15.6; 16 296; 290 293; 290

IW-31A 390–600 (8) 0.3–1.7 (7) <2–1.9 (9) 3.7–7.9 (9) 6.4–6.9 (9) 880–1,130 (9) 14.1–17.4 (9) 290–400 (7) 290–400 (7)

509; 550 0.729; 0.6 0.770*; 0.5 5.64; 5.8 6.73; 6.8 984; 996 15.8; 16 341; 340 343; 350

IW-32A 270–670 (8) 0.2–0.9 (7) <0.1–3.4 (8) 1.4–2 (8) 6.6–7 (8) 559–791 (8) 14.8–17.3 (8) 230–320 (7) 230–320 (7)

454; 390 0.414; 0.4 0.793*; 0.3 1.75; 1.7 6.8; 6.8 685; 695 16.4; 16.8 274; 280 274; 280

IW-33A 420–590 (7) 0.1–0.8 (7) <0.1–3 (8) 5.6–5.9 (7) 6.7–6.9 (7) 509–607 (7) 15.5–17.4 (7) 220–280 (7) 220–280 (7)

509; 540 0.386; 0.4 --; <2 5.8; 5.8 6.8; 6.8 568; 584 16; 15.7 250; 250 250; 250

IW-34A 150–340 (8) 0.3–1.4 (7) <0.1–3.1 (8) 0.1–0.5 (8) 6.7–7.1 (9) 515–595 (9) 15.7–16.7 (8) 200–220 (7) 200–220 (6)

221; 210 0.7; 0.7 0.521*; 0.2 0.237; 0.2 6.83; 6.8 563; 581 16.4; 16.4 213; 220 212; 215

IW-35A 350–640 (9) 0.2–0.9 (8) <0.1–3.3 (12) 0.1–0.4 (10) 6.8–7.4 (10) 1,960–2,310 (10) 12.8–17.6 (10) 310–340 (8) 310–340 (10)

503; 560 0.463; 0.45 0.902*; <2 0.23; 0.2 7.06; 7.05 2,090; 2,060 15.1; 15.7 323; 320 322; 320

IW-36A 370–690 (9) 0.1–0.4 (8) <0.1–2.8 (12) 3.3–6.1 (10) 6.4–6.9 (10) 1,690–2,030 (10) 14.4–16.9 (10) 320–430 (8) 320–440 (10)

537; 570 0.213; 0.2 0.602*; <1 4.26; 3.8 6.73; 6.8 1,870; 1,880 15.5; 15.5 364; 355 360; 350

IW-37A 440–570 (7) 0.2–0.7 (7) <0.1–3.1 (7) 2.6–7.2 (8) 6.7–6.9 (8) 903–1,030 (8) 13.7–16.8 (8) 370–390 (7) 370–390 (7)

487; 460 0.371; 0.4 --; 0.8 6.25; 6.75 6.84; 6.85 988; 995 15.3; 15.3 379; 380 379; 380

IW-38A 140–420 (8) 1.3–6.5 (7) 0.2–8.3 (8) 0.1–0.5 (9) 6.8–7.1 (9) 936–1,160 (9) 14.8–15.8 (9) 390–430 (7) 390–430 (7)

253; 235 3.07; 3.1 1.9; 0.45 0.267; 0.3 6.98; 7 1,020; 1,020 15.3; 15.3 407; 400 409; 400

Deep index wells

IW-01C 60–350 (8) 0.7–4.8 (7) 0.1–1.1 (8) 0.1–0.7 (8) 7.7–8.6 (8) 274–282 (8) 15.5–16.7 (8) 110–110 (7) 110–110 (7)

170; 150 2.04; 2 0.55; 0.5 0.312; 0.25 8.16; 8.2 279; 279 16.2; 16.3 110; 110 110; 110

IW-02C 170–300 (9) 0.3–1.6 (7) <0.1–1.6 (9) 0.1–0.3 (9) 6.7–7 (9) 284–318 (9) 15.2–15.8 (9) 110–130 (7) 110–130 (7)

214; 210 0.786; 0.7 0.698*; 0.7 0.189; 0.1 6.81; 6.8 296; 294 15.6; 15.8 119; 120 119; 120

IW-03C 120–320 (8) 0.2–0.6 (7) 0.4–4 (9) 0.1–0.3 (8) 7.3–7.5 (8) 325–346 (8) 15.6–16.1 (8) 120–130 (7) 120–130 (8)

205; 180 0.4; 0.4 1.9; 0.6 0.15; 0.1 7.4; 7.4 334; 334 15.8; 15.9 129; 130 129; 130
Appendix 81

Table A–3. Summary of physical properties and analysis of selected constituents in water samples collected as part of the Equus Beds Groundwater Recharge Project, 1995–2005.—Continued[mV, millivolts; NTU, nephelometric turbidity units; NephRatio, nephelometric ratio; NTRU, nephelometric turbidity ratio units; mg/L, milligrams per liter; μS/cm, microsiemens per centimeter at 25 degrees Celsius; CaCO3, calcium carbonate; --, not determined; MCL, Maximum Contaminant Level; SDWR, Secondary Drinking-Water Regulation; NA, not 

analyzed; <, less than; μm, micron; %, percent. The first set of numbers under each heading; for example 99–3,350, indicates the range in concentration. The number in parentheses () indicates the number of samples collected. The numbers below indicate the average followed by the median. Asterisk * is value estimated by using a log-probability regression to predict the values of data below the reporting level.]

Data-collection 

site 

(fig. 6)

Alkalinity

(mg/L CaCO3

)

Dissolved solids

(mg/L)

Suspended solids

(mg/L)

Suspended sediment 

<63 μm

(% <63 μm)

Suspended 

sediment 

(mg/L)

Drinking-water criteria -- 500 (SDWR) -- -- --

Reporting level 2.0 1.0 4.0 0.1 0.5

Shallow index wells–Continued

IW-22A 282–307 (7) 520–627 (8) <4.00–<4.00 (7) NA NA

296; 294 572; 565 --; <4.00 NA NA

IW-23A 248–307 (7) 375–461 (7) <4.00–5 (7) NA NA

275; 268 427; 423 --; <4.00 NA NA

IW-24A 230–238 (7) 536–576 (8) <4.00–<4.00 (7) NA NA

235; 236 559; 564 --; <4.00 NA NA

IW-25A 244–290 (7) 502–574 (7) <4.00–<4.00 (7) NA NA

277; 281 535; 536 --; <4.00 NA NA

IW-26A 253–305 (7) 396–469 (7) <4.00–<4.00 (7) NA NA

288; 296 419; 405 --; <4.00 NA NA

IW-27A 260–276 (7) 528–558 (7) <4.00–<4.00 (7) NA NA

269; 270 538; 534 --; <4.00 NA NA

IW-28A 204–238 (7) 580–656 (7) <4.00–<4.00 (7) NA NA

217; 213 623; 628 --; <4.00 NA NA

IW-29A 309–340 (8) 843–1,280 (10) <4.00–10 (8) NA NA

322; 319 1,050; 1,010 6.59*; 6 NA NA

IW-30A 173–200 (7) 634–785 (9) <4.00–<4.00 (7) NA NA

192; 196 715; 716 --; <4.00 NA NA

IW-31A 189–225 (7) 520–691 (7) <4.00–<4.00 (7) NA NA

199; 192 602; 620 --; <4.00 NA NA

IW-32A 172–218 (7) 356–498 (7) <4.00–<4.00 (7) NA NA

202; 211 418; 415 --; <4.00 NA NA

IW-33A 160–180 (7) 341–420 (7) <4.00–<4.00 (7) NA NA

173; 176 386; 391 --; <4.00 NA NA

IW-34A 144–157 (7) 322–388 (7) <4.00–<4.00 (7) NA NA

149; 150 360; 368 --; <4.00 NA NA

IW-35A 245–271 (8) 1,080–1,260 (10) <4.00–5 (8) NA NA

257; 255 1,190; 1,190 --; <4.00 NA NA

IW-36A 156–185 (8) 1,060–1,220 (10) <4.00–<4.00 (8) NA NA

177; 181 1,120; 1,110 --; <4.00 NA NA

IW-37A 220–249 (7) 521–689 (7) <4.00–<4.00 (7) NA NA

231; 230 614; 626 --; <4.00 NA NA

IW-38A 346–364 (7) 648–733 (7) <4.00–<4.00 (7) NA NA

354; 350 684; 675 --; <4.00 NA NA

Deep index wells

IW-01C 140–148 (7) 164–185 (7) <4.00–4 (7) NA NA

144; 144 176; 173 --; <4.00 NA NA

IW-02C 138–158 (7) 161–192 (7) <4.00–<4.00 (7) NA NA

144; 142 183; 184 --; <4.00 NA NA

IW-03C 165–171 (7) 193–209 (8) <4.00–<4.00 (7) NA NA

167; 167 203; 204 --; <4.00 NA NA
82 Water Quality in the Equus Beds Aquifer and the Little Arkansas River, South-Central Kansas Table A–3. Summary of physical properties and analysis of selected constituents in water samples collected as part of the Equus Beds Groundwater Recharge Project, 1995–2005.—Continued [mV, millivolts; NTU, nephelometric turbidity units; NephRatio, nephelometric ratio; NTRU, nephelometric turbidity ratio units; mg/L, milligrams per liter; μS/cm, microsiemens per centimeter at 25 degrees Celsius; CaCO3, calcium carbonate; --, not determined; MCL, Maxi- mum Contaminant Level; SDWR, Secondary Drinking-Water Regulation; NA, not analyzed; <, less than; μm, micron; %, percent. The first set of numbers under each heading; for example 99–3,350, indicates the range in concentration. The number in parentheses () indicates the number of samples collected. The numbers below indicate the average followed by the median. Asterisk * is value estimated by using a log-probability regression to predict the values of data below the reporting level.] Data-collection site (fig. 6) Oxidation-reduction potential (mV) Turbidity (NTU) Turbidity, NephRatio (NTRU) Dissolved oxygen (mg/L) pH (standard units) Specific conductance (μS/cm) Temperature (degrees Celsius) Carbonate hardness (mg/L CaCO3

)

Hardness

(mg/L CaCO3

)

Drinking-water criteria -- 5 (MCL) 0.5–1.0 (SDWR) -- 6.5–8.5 (SDWR) -- -- -- --

Reporting level 1.0 0.1 0.1 0.1 0.1 1.0 -5.0 1.0 1.0

Deep index wells—Continued

IW-04C 80–530 (8) 1.1–5.8 (7) <0.1–1.2 (8) 0.1–0.8 (8) 7.1–7.6 (7) 700–809 (8) 15.8–16.5 (8) 240–270 (7) 240–270 (7)

188; 120 2.43; 1.8 0.774*; 0.8 0.312; 0.2 7.29; 7.2 740; 738 16.2; 16.3 244.286; 240 244; 240

IW-05C 150–310 (7) 1–6.4 (7) 0.2–5.9 (7) 0.1–1.1 (7) 6.6–6.9 (7) 489–868 (7) 15.8–16.7 (7) 170–300 (7) 170–300 (7)

199; 180 2.61; 2.4 2.43; 2.4 0.286; 0.1 6.7; 6.7 710; 734 16.3; 16.4 247; 250 247; 250

IW-06C 90–180 (9) 1–4.5 (7) 0.1–5.4 (9) 0.1–0.2 (9) 7.1–7.4 (9) 342–359 (9) 15.4–16.4 (9) 130–140 (7) 130–140 (7)

139; 140 2.8; 2.8 1.32; 0.9 0.111; 0.1 7.21; 7.2 350; 348 15.9; 15.8 137; 140 137; 140

IW-07C 140–360 (8) 0.2–1.5 (7) <0.1–1.6 (8) 0.1–0.2 (8) 7–7.3 (8) 394–432 (8) 15.9–16.6 (8) 140–150 (7) 140–150 (7)

244; 220 0.786; 0.7 0.576*; 0.3 0.113; 0.1 7.2; 7.2 407; 404 16.3; 16.5 146; 150 146; 150

IW-08C 90–260 (10) 3.7–150 (8) <0.1–120 (14) 0.1–1.6 (10) 6.6–6.8 (10) 4,140–4,520 (10) 15.3–16.1 (10) 1,200–1,300 (8) 1,200–1,300 (11)

145; 115 26.1; 6.95 31.1*; 1.6 0.29; 0.1 6.73; 6.75 4,360; 4,330 15.7; 15.7 1,290; 1,300 1,280; 1,300

IW-09C 120–190 (9) 2.5–27 (7) 1.1–15 (9) 0–0.2 (9) 7.2–7.6 (9) 404–579 (9) 15.7–16.2 (9) 180–220 (7) 180–210 (7)

162; 160 10.8; 3.6 4.8; 4.2 0.111; 0.1 7.34; 7.3 519; 516 16; 16.1 197; 190 196; 190

IW-10C 110–150 (7) 0.6–3.2 (7) <0.1–6 (8) 0.1–0.3 (7) 6.9–7.3 (7) 278–395 (7) 15.2–15.9 (7) 120–130 (7) 120–130 (7)

130; 130 1.9; 2 1.04*; 0.3 0.157; 0.1 7.17; 7.2 354; 361 15.6; 15.5 121; 120 121; 120

IW-11C 130–190 (8) 0.3–1.4 (7) 0.2–4 (8) 0.1–0.1 (8) 7.2–7.6 (8) 379–407 (8) 15.1–16.4 (8) 84–110 (7) 84–110 (7)

160; 165 0.671; 0.5 0.863; 0.3 0.1; 0.1 7.36; 7.35 386; 384 15.9; 16.2 105; 110 105; 110

IW-12C 100–170 (10) 2.5–14 (8) <0.1–1.7 (10) 0.1–0.4 (10) 6.9–7 (10) 1,240–1,370 (10) 15.8–17.6 (10) 430–490 (8) 430–490 (8)

131; 120 6.33; 4.6 0.742*; 0.6 0.21; 0.2 6.95; 6.95 1,290; 1,290 16.4; 16.4 459; 460 460; 460

IW-13C 90–130 (8) 1.8–10 (7) <0.1–3.6 (8) 0.1–0.2 (8) 6.7–7.2 (8) 1,130–1,180 (8) 14.6–15.9 (8) 330–350 (7) 330–350 (7)

116; 120 5.31; 3.7 1.44*; 0.7 0.138; 0.1 6.96; 7 1,160; 1,160 15.4; 15.5 340; 340 341; 340

IW-14C 100–160 (8) 2.1–12 (8) <0.1–1.9 (8) 0.1–0.2 (8) 6.7–7 (8) 1,390–1,540 (8) 15.5–16.2 (8) 470–530 (8) 470–530 (8)

134; 130 6.1; 4.9 0.821*; 0.6 0.138; 0.1 6.93; 7 1,440; 1,410 15.9; 16 495; 490 496; 490

IW-15C 130–370 (8) <0.1–0.2 (7) <0.1–4.2 (8) 0.1–0.2 (8) 7–7.3 (8) 898–957 (8) 15.7–16.5 (8) 340–360 (7) 340–360 (7)

231; 230 0.123*; 0.1 --; <0.1 0.113; 0.1 7.16; 7.2 940; 945 16.2; 16.3 349; 350 349; 350

IW-16C 120–180 (8) 0.9–5.7 (7) <0.1–3.4 (8) 0.1–0.3 (8) 6.4–6.8 (8) 757–930 (8) 15–16.2 (8) 320–380 (7) 320–380 (7)

153; 150 2.86; 2.1 2.59*; 2.4 0.162; 0.15 6.69; 6.8 840; 822 15.5; 15.5 349; 340 349; 340

IW-17C 50–120 (8) 1.3–7.8 (7) 0.3–3.1 (8) 0.1–0.2 (8) 7.1–7.4 (9) 443–538 (9) 15–16.5 (9) 160–190 (7) 160–190 (7)

90; 90 4.7; 4.7 1.16; 0.65 0.125; 0.1 7.28; 7.3 517; 525 15.9; 16.1 169; 160 169; 160

IW-18C 110–280 (8) 0.7–3.3 (7) <0.1–6.4 (8) 0–0.5 (9) 7–7.3 (9) 972–1,020 (9) 14.4–16.3 (9) 290–320 (7) 290–320 (7)

171; 160 2.16; 1.8 2.77*; 1.2 0.167; 0.1 7.11; 7.1 992; 993 15.6; 15.8 307; 310 307; 310

IW-19C 170–240 (7) 0.9–18 (7) 0.6–9.7 (7) 0.1–0.2 (7) 6.9–7.2 (7) 917–952 (7) 14.8–15.7 (7) 250–260 (7) 250–260 (7)

194; 190 5.03; 3.1 4.89; 3.8 0.157; 0.2 7.06; 7.1 944; 949 15.3; 15.3 259; 260 259; 260

IW-20C 120–170 (9) 1.4–12 (8) <0.1–22 (12) 0.1–0.2 (9) 6.9–7.1 (9) 1,150–1,330 (9) 15.4–16.2 (9) 460–530 (8) 450–530 (10)

133; 120 4.94; 4.4 5.61*; 0.2 0.133; 0.1 7; 7 1,260; 1,260 15.9; 15.9 496; 500 493; 495

IW-21C 100–140 (8) 3.1–27 (8) 0.1–110 (9) 0.1–0.3 (8) 6.7–6.9 (8) 1,610–1,710 (8) 15.2–15.9 (8) 650–680 (8) 650–680 (8)

118; 115 12.1; 9.1 12.8; 0.5 0.175; 0.1 6.79; 6.8 1,670; 1,670 15.6; 15.6 664; 665 665; 670

IW-22C 90–140 (9) 0.3–4.5 (7) <0.1–5.1 (9) 0.1–0.4 (9) 6.7–7.3 (9) 684–708 (9) 15.8–16.4 (9) 230–250 (7) 230–250 (7)

123; 120 2.51; 2.3 0.939*; 0.5 0.167; 0.1 7.13; 7.2 689; 686 16.1; 16.1 239; 240 239; 240

IW-23C 140–290 (7) 1.1–4.7 (7) 0.1–2.8 (7) 0.1–1.7 (6) 7–7.3 (8) 588–663 (8) 15–17.1 (8) 190–210 (7) 190–210 (7)

179; 160 2.13; 1.7 1.26; 0.7 0.383; 0.1 7.15; 7.15 647; 656 16.2; 16.2 203; 200 204; 210

IW-24C 390–530 (9) 0.1–1.6 (7) <0.1–0.9 (10) <0.010–0.2 (10) 7–7.4 (10) 1,040–1,210 (10) 15.3–16.6 (10) 180–200 (7) 180–200 (8)

479; 480 0.657; 0.6 0.754*; 0.6 0.122*; 0.1 7.27; 7.35 1,150; 1,150 16.1; 16.2 186; 180 186; 185
Appendix 83

Table A–3. Summary of physical properties and analysis of selected constituents in water samples collected as part of the Equus Beds Groundwater Recharge Project, 1995–2005.—Continued[mV, millivolts; NTU, nephelometric turbidity units; NephRatio, nephelometric ratio; NTRU, nephelometric turbidity ratio units; mg/L, milligrams per liter; μS/cm, microsiemens per centimeter at 25 degrees Celsius; CaCO3, calcium carbonate; --, not determined; MCL, Maximum Contaminant Level; SDWR, Secondary Drinking-Water Regulation; NA, not 

analyzed; <, less than; μm, micron; %, percent. The first set of numbers under each heading; for example 99–3,350, indicates the range in concentration. The number in parentheses () indicates the number of samples collected. The numbers below indicate the average followed by the median. Asterisk * is value estimated by using a log-probability regression to predict the values of data below the reporting level.]

Data-collection 

site 

(fig. 6)

Alkalinity

(mg/L CaCO3

)

Dissolved solids

(mg/L)

Suspended solids

(mg/L)

Suspended sediment 

<63 μm

(% <63 μm)

Suspended 

sediment 

(mg/L)

Drinking-water criteria -- 500 (SDWR) -- -- --

Reporting level 2.0 1.0 4.0 0.1 0.5

Deep index wells—Continued

IW-04C 164–173 (7) 394–491 (7) <4.00–9 (7) NA NA

169; 168 434; 443 --; <4.00 NA NA

IW-05C 121–139 (7) 291–613 (7) <4.00–11 (7) NA NA

129; 128 461; 453 6.18*; 6 NA NA

IW-06C 17–175 (7) 201–223 (7) <4.00–4 (7) NA NA

147; 165 212; 211 --; <4.00 NA NA

IW-07C 151–169 (7) 236–262 (7) <4.00–<4.00 (7) NA NA

155; 153 248; 245 --; <4.00 NA NA

IW-08C 189–199 (8) 2,380–3,230 (11) 8–24 (8) NA NA

195; 195 2,690; 2,710 13.9; 12.5 NA NA

IW-09C 188–197 (7) 292–336 (7) 4–40 (7) NA NA

194; 195 310; 306 15.3; 10 NA NA

IW-10C 136–148 (7) 206–254 (7) <4.00–<4.00 (7) NA NA

140; 140 219; 210 --; <4.00 NA NA

IW-11C 171–186 (7) 229–264 (7) <4.00–<4.00 (7) NA NA

180; 182 242; 244 --; <4.00 NA NA

IW-12C 350–395 (8) 792–912 (8) <4.00–12 (8) NA NA

372; 374 860; 870 5.92*; 6 NA NA

IW-13C 246–270 (7) 651–704 (7) <4.00–10 (7) NA NA

253; 252 683; 688 5.91*; 6 NA NA

IW-14C 263–284 (8) 928–1,010 (8) <4.00–8 (8) NA NA

272; 271 966; 968 --; <4.00 NA NA

IW-15C 200–212 (7) 571–616 (7) <4.00–<4.00 (7) NA NA

206; 206 596; 600 --; <4.00 NA NA

IW-16C 144–170 (7) 541–640 (7) <4.00–12 (7) NA NA

156; 155 582; 565 7.55*; 7 NA NA

IW-17C 220–337 (7) 315–330 (7) <4.00–12 (7) NA NA

240; 226 321; 321 --; <4.00 NA NA

IW-18C 252–264 (7) 567–596 (7) <4.00–6 (7) NA NA

256; 255 580; 581 --; <4.00 NA NA

IW-19C 267–274 (7) 539–568 (7) <4.00–26 (7) NA NA

271; 272 557; 563 --; <4.00 NA NA

IW-20C 226–247 (8) 830–986 (10) <4.00–5 (8) NA NA

238; 238 893; 898 --; <4.00 NA NA

IW-21C 262–292 (8) 1,150–1,240 (8) 7–19 (8) NA NA

275; 276 1,200; 1,210 13.8; 12.5 NA NA

IW-22C 244–256 (7) 420–453 (7) <4.00–4 (7) NA NA

252; 254 434; 432 --; <4.00 NA NA

IW-23C 238–266 (7) 382–416 (7) <4.00–14 (7) NA NA

255; 255 400; 396 --; <4.00 NA NA

IW-24C 235–246 (7) 646–677 (8) <4.00–<4.00 (7) NA NA

242; 242 663; 664 --; <4.00 NA NA
84 Water Quality in the Equus Beds Aquifer and the Little Arkansas River, South-Central Kansas Table A–3. Summary of physical properties and analysis of selected constituents in water samples collected as part of the Equus Beds Groundwater Recharge Project, 1995–2005.—Continued [mV, millivolts; NTU, nephelometric turbidity units; NephRatio, nephelometric ratio; NTRU, nephelometric turbidity ratio units; mg/L, milligrams per liter; μS/cm, microsiemens per centimeter at 25 degrees Celsius; CaCO3, calcium carbonate; --, not determined; MCL, Maxi- mum Contaminant Level; SDWR, Secondary Drinking-Water Regulation; NA, not analyzed; <, less than; μm, micron; %, percent. The first set of numbers under each heading; for example 99–3,350, indicates the range in concentration. The number in parentheses () indicates the number of samples collected. The numbers below indicate the average followed by the median. Asterisk * is value estimated by using a log-probability regression to predict the values of data below the reporting level.] Data-collection site (fig. 6) Oxidation-reduction potential (mV) Turbidity (NTU) Turbidity, NephRatio (NTRU) Dissolved oxygen (mg/L) pH (standard units) Specific conductance (μS/cm) Temperature (degrees Celsius) Carbonate hardness (mg/L CaCO3

)

Hardness

(mg/L CaCO3

)

Drinking-water criteria -- 5 (MCL) 0.5–1.0 (SDWR) -- 6.5–8.5 (SDWR) -- -- -- --

Reporting level 1.0 0.1 0.1 0.1 0.1 1.0 -5.0 1.0 1.0

Deep index wells—Continued

IW-25C 300–550 (9) 0.2–1.7 (8) <0.1–4.8 (11) 0.1–0.3 (9) 6.7–7.4 (9) 818–1,130 (9) 15.2–16 (9) 190–300 (8) 190–300 (10)

436; 430 0.488; 0.35 0.846*; 0.4 0.167; 0.2 7.13; 7.2 963; 952 15.7; 15.7 258; 260 252; 240

IW-26C 330–500 (6) 0.1–0.2 (6) <0.1–2.9 (6) 0.1–0.2 (6) 7.2–7.3 (6) 903–913 (6) 16–16.8 (6) 260–280 (6) 260–280 (6)

412; 425 0.167; 0.2 --; 0.1 0.133; 0.1 7.22; 7.2 907; 905 16.4; 16.4 265; 260 265; 260

IW-27C 220–460 (8) 0.1–28 (7) <0.1–50 (8) 0–0.4 (8) 6.8–7.3 (8) 756–850 (8) 15.9–16.4 (8) 220–230 (7) 220–230 (7)

316; 310 4.47; 0.7 7.31*; 0.3 0.138; 0.1 7.18; 7.2 801; 801 16.2; 16.2 223; 220 226; 230

IW-28C 200–480 (8) 0.2–0.7 (7) <0.1–3.4 (8) 0.1–0.2 (7) 6.7–7.4 (8) 837–880 (8) 16.1–16.6 (8) 220–240 (7) 220–240 (7)

369; 380 0.386; 0.4 0.605*; 0.3 0.143; 0.1 7.2; 7.25 856; 857 16.4; 16.5 231; 230 233; 230

IW-29C 100–150 (7) 1.8–8.4 (7) <0.1–4 (7) 0.1–0.2 (6) 6.9–7.1 (7) 902–950 (7) 15.5–16.7 (7) 260–300 (7) 260–310 (7)

126; 140 5.21; 4 1.53*; 1.1 0.133; 0.1 7.01; 7 931; 943 16.1; 16.1 286; 290 287; 290

IW-30C 250–520 (9) 0.1–0.8 (8) <0.1–4 (12) 0.1–0.4 (9) 6.9–7.4 (9) 1,080–1,520 (9) 15.8–16.5 (9) 350–390 (8) 350–390 (11)

447; 490 0.375; 0.4 1.01*; 0.2 0.156; 0.1 7.21; 7.2 1,410; 1,500 16.2; 16.3 366; 365 365; 360

IW-31C 230–470 (8) 0.2–1.4 (7) <0.1–4.2 (9) 0–1.6 (9) 6.8–7.3 (8) 790–1,080 (9) 15.1–17 (9) 300–320 (7) 290–320 (8)

331; 330 0.629; 0.6 1.39*; 1.2 0.3; 0.1 7.11; 7.15 994; 1,010 16.6; 16.7 310; 310 309; 310

IW-32C 200–530 (8) 0.2–3.2 (7) <0.1–3.9 (8) <0.010–0.2 (8) 7–7.3 (8) 761–783 (8) 15.9–16.5 (8) 240–260 (7) 240–260 (7)

408; 415 0.914; 0.5 0.681*; 0.2 0.109*; 0.1 7.18; 7.2 772; 772 16.3; 16.3 247; 250 247; 250

IW-33C 200–510 (7) 0.4–4 (7) <0.1–4.1 (7) 0.1–0.4 (7) 7.1–7.3 (7) 759–838 (7) 15.9–16.5 (7) 240–260 (7) 240–260 (7)

391; 450 1.14; 0.8 1.48*; 1.1 0.214; 0.2 7.2; 7.2 821; 832 16.2; 16.1 251; 250 251; 250

IW-34C 290–500 (8) <0.1–0.4 (7) <0.1–3.6 (8) 0.1–0.5 (9) 7–7.4 (9) 726–771 (9) 15.6–16.7 (9) 230–260 (7) 240–260 (6)

374; 355 0.191*; 0.1 --; <0.1 0.2; 0.2 7.19; 7.2 751; 751 16.3; 16.4 247; 250 250; 250

IW-35C 330–630 (9) <0.1–5.5 (8) <0.1–3.7 (11) 0.1–0.3 (10) 6.7–7.2 (10) 1,290–1,460 (10) 14.8–16.1 (10) 340–370 (8) 340–370 (10)

471; 490 1.08*; 0.2 1.57*; 0.3 0.18; 0.2 7.01; 7.05 1,360; 1,360 15.5; 15.6 353; 350 352; 350

IW-36C 370–640 (8) 0.1–2.8 (7) <0.1–3.1 (8) 0.5–1.7 (8) 6.7–7.2 (9) 983–1,770 (9) 15.4–16.6 (9) 320–560 (7) 320–560 (7)

495; 495 0.686; 0.3 0.973*; 0.2 1.23; 1.3 7.01; 7.1 1,290; 1,300 16.1; 16.3 409; 390 410; 400

IW-37C 310–500 (7) 0.2–0.5 (7) <0.1–4.5 (7) 0.1–0.2 (8) 7–7.2 (8) 759–801 (8) 15.4–16.7 (8) 220–240 (7) 220–240 (7)

409; 400 0.314; 0.3 --; 0.5 0.125; 0.1 7.16; 7.2 772; 767 16.1; 16.1 234; 240 234; 240

IW-38C 240–500 (9) 0.1–0.8 (7) <0.1–3.4 (9) 0.1–0.3 (10) 6.8–7.2 (10) 722–833 (10) 14.5–15.7 (10) 310–340 (7) 310–350 (7)

349; 380 0.457; 0.4 0.790*; 0.5 0.14; 0.1 7.04; 7.1 791; 804 15.3; 15.3 319; 320 320; 320
Appendix 85

Table A–3. Summary of physical properties and analysis of selected constituents in water samples collected as part of the Equus Beds Groundwater Recharge Project, 1995–2005.—Continued[mV, millivolts; NTU, nephelometric turbidity units; NephRatio, nephelometric ratio; NTRU, nephelometric turbidity ratio units; mg/L, milligrams per liter; μS/cm, microsiemens per centimeter at 25 degrees Celsius; CaCO3, calcium carbonate; --, not determined; MCL, Maximum Contaminant Level; SDWR, Secondary Drinking-Water Regulation; NA, not 

analyzed; <, less than; μm, micron; %, percent. The first set of numbers under each heading; for example 99–3,350, indicates the range in concentration. The number in parentheses () indicates the number of samples collected. The numbers below indicate the average followed by the median. Asterisk * is value estimated by using a log-probability regression to predict the values of data below the reporting level.]

Data-collection 

site 

(fig. 6)

Alkalinity

(mg/L CaCO3)

Dissolved solids

(mg/L)

Suspended solids

(mg/L)

Suspended sediment 

<63 μm

(% <63 μm)

Suspended 

sediment 

(mg/L)

Drinking-water criteria -- 500 (SDWR) -- -- --

Reporting level 2.0 1.0 4.0 0.1 0.5

Deep index wells—Continued

IW-25C 247–284 (8) 520–661 (10) <4.00–<4.00 (8) NA NA

262; 261 565; 553 --; <4.00 NA NA

IW-26C 263–283 (6) 525–580 (6) <4.00–<4.00 (6) NA NA

273; 273 544; 537 --; <4.00 NA NA

IW-27C 266–274 (7) 450–494 (7) <4.00–514 (7) NA NA

271; 272 478; 484 --; <4.00 NA NA

IW-28C 263–282 (7) 517–538 (7) <4.00–<4.00 (7) NA NA

275; 277 524; 524 --; <4.00 NA NA

IW-29C 265–284 (7) 554–622 (7) <4.00–6 (7) NA NA

275; 274 593; 590 --; <4.00 NA NA

IW-30C 214–226 (8) 928–953 (11) <4.00–<4.00 (8) NA NA

222; 223 942; 946 --; <4.00 NA NA

IW-31C 247–262 (7) 601–637 (8) <4.00–<4.00 (7) NA NA

257; 258 618; 616 --; <4.00 NA NA

IW-32C 245–260 (7) 450–476 (7) <4.00–<4.00 (7) NA NA

252; 250 462; 460 --; <4.00 NA NA

IW-33C 259–274 (7) 471–518 (7) <4.00–5 (7) NA NA

268; 270 506; 513 --; <4.00 NA NA

IW-34C 260–274 (7) 438–478 (7) <4.00–<4.00 (7) NA NA

269; 270 456; 455 --; <4.00 NA NA

IW-35C 167–192 (8) 726–891 (10) <4.00–9 (8) NA NA

182; 186 798; 788 --; <4.00 NA NA

IW-36C 213–241 (7) 592–1090 (7) <4.00–5 (7) NA NA

227; 228 770; 740 --; <4.00 NA NA

IW-37C 234–250 (7) 445–474 (7) <4.00–<4.00 (7) NA NA

241; 240 457; 459 --; <4.00 NA NA

IW-38C 278–310 (7) 475–546 (7) <4.00–<4.00 (7) NA NA

290; 286 511; 505 --; <4.00 NA NA
86 Water Quality in the Equus Beds Aquifer and the Little Arkansas River, South-Central Kansas Table A–4. Summary of major-ion and nutrient concentrations in water samples collected as part of the Equus Beds Groundwater Recharge Project, 1995–2005. [mg/L, milligrams per liter; --, not determined; DWA, Drinking-Water Advisory; SDWR, Secondary Drinking-Water Regulation; <, less than; MCL, Maximum Contaminant Level; NA, not analyzed. The first set of numbers under each heading, for example 99–3,350, indicates the range in concentration. The number in parentheses () indicates the number of samples collected. The numbers below indicate the average followed by the median. Asterisk * is value estimated by using a log-probability regression to predict the values of data below the reporting level.] Data-collection site (fig. 6) Calcium (mg/L) Magnesium (mg/L) Potassium (mg/L) Sodium (mg/L) Bicarbonate (mg/L) Carbonate (mg/L) Bromide (mg/L) Chloride (mg/L) Fluoride (mg/L) Drinking-water criteria -- -- -- 20 (DWA) -- -- -- 250 (SDWR) 2 (SDWR) Reporting level 0.03 0.05 0.07 0.05 2.0 1.0 0.03 5.0 0.02 Surface-water monitoring sites (Little Arkansas River) 7143672 (near Halstead) 8.25–174 (186) 1.6–36.2 (186) 4.4–18.1 (186) 4.38–498 (186) 3.7–460 (185) 0–16 (185) 0–1.7 (84) 8–932 (187) 0.04–2.74 (85) 84.2; 93.8 13.7; 14.5 7.96; 8 86.9; 83.4 215; 250 0.556; 0 0.462; 0.3 165; 150 0.32; 0.25 7144100 (near Sedgwick) 4.74–128 (161) 1.01–23.9 (161) 4.43–10.6 (161) 1.5–132 (161) 22–360 (160) 0–12 (160) 0–1 (86) 5–305 (165) 0.11–0.82 (87) 61.3; 60.7 11.3; 11.2 7.24; 7.35 49.3; 47.1 187; 180 0.842; 0 0.239; 0.2 80.1; 68 0.27; 0.24 Diversion well site near Halstead Diversion well 57.4–108 (150) 8.16–14.8 (150) 1.84–2.82 (150) 51.2–74.5 (150) 120–340 (150) 0–4 (150) 0.03–0.3 (35) 22–77.8 (315) 0.02–0.32 (35) 87.1; 91.1 12.5; 13.3 2.34; 2.36 63.3; 63.8 314; 320 0.073; 0 0.187; 0.2 56.4; 59.6 0.219; 0.23 EB-145-A1 49.5–141 (66) 6.93–22.7 (66) 4.41–9.87 (66) 60.2–125 (66) 200–470 (65) 0–1 (65) 0.3–0.8 (32) 80–275 (66) 0.15–0.52 (33) 102; 106 15; 15 7.11; 7.13 84.4; 81.5 342; 360 0.046; 0 0.553; 0.6 156; 158 0.33; 0.33 EB-145-A2 89.7–140 (28) 12.6–18.6 (28) 2.82–4.62 (28) 78.4–112 (28) 300–440 (28) 0–1 (28) 0.4–0.6 (13) 138–203 (28) 0.1–0.26 (13) 112; 110 14.9; 14.7 3.4; 3.39 91.2; 91.9 360; 360 0.036; 0 0.477; 0.5 162; 160 0.2; 0.2 EB-145-A3 114–151 (33) 14.8–19.2 (33) 2.56–3.5 (33) 84.6–113 (33) 300–510 (33) --–0 (33) 0.2–0.5 (13) 59.9–178 (33) 0.02–0.32 (13) 131; 129 17.1; 17.3 2.91; 2.9 96.6; 96.3 435; 440 --; -- 0.354; 0.4 135; 145 0.17; 0.17 EB-145-A4 56.5–142 (21) 7.17–18 (21) 1.78–2.85 (21) 49.8–74.2 (21) 270–400 (21) 0–1 (21) 0.1–0.3 (9) 10–58 (21) 0.13–0.3 (9) 94.7; 93.9 12; 11.1 2.34; 2.31 59.9; 56.3 327; 310 0.048; 0 0.133; 0.1 30.5; 23.1 0.23; 0.25 EB-145-A5 86.2–123 (32) 10.1–16 (32) 2.09–2.79 (32) 48.8–76 (32) 320–400 (32) --–0 (32) 0.1–0.1 (15) 26.7–54 (32) 0.13–0.31 (15) 106; 108 13; 13.1 2.47; 2.5 53.3; 52.6 372; 375 --; -- 0.1; 0.1 33.3; 32 0.23; 0.25 EB-145-P-D5 44.8–102 (58) 6.45–15.2 (58) 1.74–3.09 (58) 48.7–79.4 (58) 230–350 (58) <1–<1 (58) 0–17 (28) 14–134 (58) 0.1–0.38 (28) 68.3; 69.4 10.1; 10.3 2.24; 2.25 62.4; 63.2 280; 290 --; <1 0.79; 0.2 52; 50.5 0.28; 0.29 Halstead recharge site SMW-H4 46.9–100 (47) 7.79–19.8 (47) 1.39–3.49 (47) 29.8–82.6 (47) 180–330 (47) --–0 (47) 0.1–0.2 (27) 19.9–87 (47) 0.11–0.4 (27) 79.3; 79.5 13.3; 13.4 2.36; 2.32 54.3; 54 262; 260 --; -- 0.193; 0.2 49.7; 52 0.29; 0.32 SMW-H14 61.8–113 (46) 11.4–20.5 (46) 2.05–4.55 (46) 54.8–247 (46) 230–360 (46) 0–1 (46) 0.03–0.3 (28) 54.7–412 (46) 0.02–0.54 (28) 87.9; 88.8 14.4; 14.4 2.96; 2.89 87.3; 68.6 291; 300 0.043; 0 0.197; 0.2 105; 66.1 0.26; 0.25 DMW-H1 37.3–103 (46) 6.06–16.8 (46) 2.04–3.22 (46) 29.4–74.5 (46) 180–340 (46) --–0 (46) 0–0.2 (27) 7.3–79 (46) 0.15–0.42 (27) 85.7; 91.8 13.2; 14.1 2.65; 2.68 62.1; 67 305; 320 --; -- 0.156; 0.2 52.3; 59 0.26; 0.25 DMW-H13 37.2–105 (46) 4.41–13.9 (46) 1.89–3.46 (46) 27.3–73.4 (46) 180–340 (46) 0–1 (46) <0.03–0.2 (28) 5.8–133 (46) 0.02–0.32 (28) 81.6; 91.5 11.1; 12.9 2.66; 2.76 57.8; 65.3 293; 320 0.043; 0 0.184*; 0.2 50; 59.4 0.23; 0.24 Sedgwick recharge site Treated stream water 21.7–126 (48) 4.15–23.7 (48) 3.41–10.2 (48) 11.9–127 (48) 5.3–320 (48) 0–19 (48) 0.1–0.4 (15) 13–227 (227) 0.15–0.31 (15) 58.8; 54 11.1; 10 6.97; 6.91 44.3; 37.1 182; 170 1.94; 0 0.173; 0.1 76.8; 62.3 0.22; 0.21

SMW-S11 45.7–143 (52) 7.93–20.3 (52) 2.18–7.03 (52) 13.6–104 (52) 130–300 (52) <1–<1 (52) 0.1–0.4 (23) 4.5–156 (52) 0.17–0.63 (23)

77.2; 72.8 12; 11.2 3.88; 3.64 42; 38.3 192; 190 --; <1 0.143; 0.1 45.2; 28.8 0.34; 0.32

SMW-S13 47.7–111 (47) 8.55–18.8 (47) 2.17–5.24 (47) 19.6–56.6 (47) 130–220 (47) 0–1 (47) 0–0.3 (22) 7.7–105 (47) 0.3–0.61 (21)

72.6; 72.5 12.3; 11.5 3.34; 2.84 37.2; 35.6 163; 160 0.043; 0 0.136; 0.1 48; 46 0.41; 0.41

DMW-S10 69.4–80.5 (40) 13.8–15.8 (40) 3.17–3.79 (40) 77.9–92.7 (40) 240–360 (40) <1–<1 (40) 0.1–0.1 (22) 49–70.5 (40) 0.3–0.51 (22)

74.4; 74 14.5; 14.4 3.45; 3.44 83.6; 83.2 335; 340 --; <1 0.1; 0.1 62.4; 63 0.39; 0.39

DMW-S14 47.3–68.2 (36) 9.4–13.1 (36) 2.53–3.25 (36) 59.6–88.8 (36) 180–330 (36) <1–<1 (36) 0–0.1 (20) 19–51.7 (36) 0.25–0.45 (20)

54.1; 53.3 10.9; 10.7 2.87; 2.88 73.5; 72.5 276; 270 --; <1 0.09; 0.1 27.2; 24 0.34; 0.35
Appendix 87

Table A–4. Summary of major-ion and nutrient concentrations in water samples collected as part of the Equus Beds Groundwater Recharge Project, 1995–2005.—Continued[mg/L, milligrams per liter; --, not determined; DWA, Drinking-Water Advisory; SDWR, Secondary Drinking-Water Regulation; <, less than; MCL, Maximum Contaminant Level; NA, not analyzed. The first set of numbers under each heading, for example 99–3,350, indicates the range in concentration. The number in parentheses () indicates the number of samples collected. The numbers below indicate the average followed by the median. Asterisk * is value estimated 

by using a log-probability regression to predict the values of data below the reporting level.]

Data-collection site 

(fig. 6)

Sulfate

(mg/L)

Ammonia as nitrogen

(mg/L)

Nitrate as nitrogen, 

dissolved 

(mg/L)

Nitrate as nitrogen,

total 

(mg/L)

Nitrite plus nitrate as 

nitrogen, dissolved 

(mg/L)

Nitrite plus nitrate 

as nitrogen, total 

(mg/L)

Nitrite as nitrogen, 

dissolved 

(mg/L)

Nitrite as nitrogen,

total 

(mg/L)

Phosphorus, 

total 

(mg/L)

Drinking-water criteria 250 (SDWR) -- 10 (MCL) 10 (MCL) 10 (MCL) 10 (MCL) 1 (MCL) 1 (MCL) --

Reporting level 5.0 0.03 0.01 0.01 0.02 0.02 0.02 0.02 0.01

Surface-water monitoring sites (Little Arkansas River)

7143672 (near Halstead)

5–312 (186) <0.03–0.64 (168) <0.01–2.76 (80) 0.1–0.76 (6) <0.02–2.86 (153) <0.02–0.78 (10) <0.008–1.18 (85) <0.01–0.09 (7) 0.21–2.3 (72)

40.9; 42.2 0.112*; 0.07 0.756*; 0.76 0.307; 0.21 0.696*; 0.51 0.246*; 0.17 0.050*; <0.02 --; <0.01 0.62; 0.495

7144100 (near Sedgwick)

5–211 (161) <0.03–0.86 (153) 0.01–9.36 (84) 0.64–1.26 (5) 0.01–9.42 (153) 0.67–1.36 (5) <0.01–1.46 (87) 0.01–0.1 (5) 0.07–2.03 (69)

38; 37 0.117*; 0.08 1.25; 1.11 --; -- 1.18; 1.07 --; -- 0.074*; 0.02 --; -- 0.758; 0.67

Diversion well site near Halstead

Diversion well 5–111 (150) 0.03–0.47 (142) <0.01–0.01 (33) <0.01–<0.01 (3) <0.02–0.78 (111) <0.02–<0.02 (6) <0.01–0.02 (34) <0.01–<0.01 (3) NA

57.6; 64.6 0.244; 0.245 --; <0.01 --; -- 0.018; <0.02 --; <0.02 --; <0.02 --; -- NA

EB-145-A1 <5–35 (66) 1.04–12.6 (66) <0.01–0.02 (29) --–<0.01 (1) <0.02–0.79 (65) <0.02–<0.02 (3) <0.008–<0.02 (32) <0.01–<0.01 (3) 0.09–2.55 (4)

7.67*; <5 2.11; 1.9 --; <0.01 --; -- <0.02; <0.02 --; -- --; <0.02 --; -- --; --

EB-145-A2 <5–22.4 (27) 0.47–1.13 (28) <0.01–0.02 (12) --–<0.01 (1) <0.02–0.02 (28) --–<0.02 (1) <0.01–<0.02 (12) --–<0.01 (1) --–0.58 (1)

6.083*; <5 0.734; 0.696 --; <0.01 --; -- --; <0.02 --; -- --; <0.02 --; -- --; --

EB-145-A3 <5–163 (32) 0.19–0.33 (33) <0.01–0.01 (13) NA <0.02–0.03 (32) NA <0.01–<0.02 (12) NA NA

39.154*; 21.6 0.261; 0.26 --; <0.01 NA --; <0.02 NA --; <0.02 NA NA

EB-145-A4 30–177 (21) 0.16–0.291 (21) <0.01–0.02 (8) NA <0.02–0.53 (21) NA <0.01–0.01 (9) NA NA

87.4; 64 0.228; 0.22 --; <0.01 NA --; <0.02 NA --; <0.02 NA NA

EB-145-A5 46.8–116 (32) 0.166–0.343 (32) <0.01–0.02 (15) NA <0.02–0.02 (32) NA <0.01–<0.02 (14) NA NA

72.1; 72 0.239; 0.24 --; <0.01 NA --; <0.02 NA --; <0.02 NA NA

EB-145-P-D5 5–70 (58) 0.172–2.56 (58) <0.01–0.11 (27) --–<0.01 (1) <0.02–0.15 (58) --–<0.02 (1) <0.01–<0.02 (27) --–<0.01 (1) --–0.26 (1)

35.9; 33 0.324; 0.27 <0.01; <0.01 --; -- 0.018*; <0.02 --; -- --; <0.02 --; -- --; --

Halstead recharge site

SMW-H4 29–76 (47) <0.03–0.26 (47) 0.01–19.4 (27) NA 0.02–19.4 (47) NA <0.02–0.02 (26) NA NA

52.2; 47.9 0.054*; 0.04 7.22; 6.13 NA 5.35; 2 NA --; <0.02 NA NA

SMW-H14 25.6–91 (46) <0.03–0.18 (46) 0.01–9.5 (28) NA 0.01–9.5 (46) NA <0.02–0.04 (27) NA NA

60.5; 61 0.049*; 0.04 2.48; 1.31 NA 1.58; 0.64 NA --; <0.02 NA NA

DMW-H1 19.4–110 (46) 0.03–1.64 (46) <0.01–1 (26) NA <0.02–1.02 (46) NA <0.02–0.02 (26) NA NA

66; 72.5 0.242; 0.23 <0.01; <0.01 NA 0.050*; <0.02 NA --; <0.02 NA NA

DMW-H13 9.7–107 (46) 0.033–0.275 (46) <0.01–3.89 (26) NA <0.02–3.89 (46) NA <0.02–0.02 (26) NA NA

59.5; 70.1 0.189; 0.2 <0.01; <0.01 NA 0.145*; <0.02 NA --; <0.02 NA NA

Sedgwick recharge site

Treated stream water 14–105 (48) <0.03–0.21 (48) 0.4–2.27 (15) NA 0.05–2.78 (48) NA <0.02–0.06 (15) NA NA

37.9; 33.8 0.056*; 0.05 1.18; 1.14 NA 1.13; 1 NA 0.025*; 0.02 NA NA

SMW-S11 4.6–274 (52) <0.03–0.18 (52) 0.01–15 (23) NA <0.02–15.3 (52) NA <0.02–0.08 (23) NA NA

74.6; 61.1 0.038*; 0.02 7.37; 9.7 NA 5.418*; 3.02 NA --; <0.02 NA NA

SMW-S13 31–196 (47) <0.01–0.12 (47) 0.86–11 (22) NA 0.02–11 (47) NA <0.02–0.15 (22) NA NA

85.7; 69 0.032*; <0.03 6.21; 7.54 NA 4.94; 3.38 NA --; <0.02 NA NA

DMW-S10 41–60 (40) <0.03–0.18 (40) 0.01–1.47 (22) NA 0.02–1.47 (40) NA <0.02–<0.02 (22) NA NA

50.3; 50.1 0.041*; 0.03 0.16; 0.095 NA 0.16; 0.12 NA --; <0.02 NA NA

DMW-S14 41–63.3 (36) <0.01–0.11 (36) 1.04–4.91 (20) NA 0.04–5.5 (36) NA <0.02–0.07 (20) NA NA

51.1; 51.9 0.034*; <0.03 3.98; 4.14 NA 3.53; 3.92 NA 0.033*; 0.03 NA NA
88 Water Quality in the Equus Beds Aquifer and the Little Arkansas River, South-Central Kansas Table A

–4. Summary of major-ion and nutrient concentrations in water samples collected as 

part of the Equus Beds Groundwater Recharge Project, 1995–2005.—Continued[mg/L, milligrams per liter; --, not determined; DWA, Drinking-Water Advisory; SDWR, Secondary Drinking-Water Regulation; <, less than; MCL, Maximum Contaminant Level; NA, not analyzed. The first set of numbers under each heading, for example 99–3,350, indicates the range in concentration. The number in parentheses () indicates the number of samples collected. The numbers below indicate the average followed by the median. Asterisk * is value estimated by using a log-probability regression to 

predict the values of data below the reporting level.]

Data-collection site 

(fig. 6)

Orthophosphate 

(mg/L)

Orthophosphate as phosphorous 

(mg/L)

Organic carbon, total 

(mg/L)

Drinking-water criteria -- -- --Reporting level 0.01 0.01 0.2

Surface-water monitoring sites (Little Arkansas River)

7143672 (near Halstead)

0.123–1.38 (83) 0.01–0.45 (86) 3.9–26.7 (52)

0.699; 0.675 0.226; 0.22 9.87; 8.7

7144100 (near Sedgwick)

0.113–4.75 (86) 0.037–1.55 (87) 0.6–30.4 (54)

1.01; 0.874 0.331; 0.29 9.65; 8.1

Diversion well site near Halstead

Diversion well 0.184–0.8 (33) 0.01–0.26 (36) 1–2.2 (31)

0.353; 0.307 0.114; 0.1 1.34; 1.3

EB-145-A1 0.061–6.71 (32) 0.02–2.19 (33) 3–6.8 (19)

2.07; 2.29 0.685; 0.75 4.79; 4.7

EB-145-A2 0.061–1.17 (12) 0.02–0.38 (13) 3.4–4.4 (10)

0.481; 0.414 0.148; 0.13 3.88; 3.8

EB-145-A3 0.092–0.767 (13) 0.03–0.25 (13) 2.1–3.3 (10)

0.366; 0.337 0.119; 0.11 2.83; 3

EB-145-A4 0.215–0.552 (9) 0.07–0.18 (9) 0.6–1.7 (7)

0.389; 0.368 0.127; 0.12 1.13; 1.1

EB-145-A5 0.307–0.521 (15) 0.1–0.17 (15) 0.8–1 (8)

0.38; 0.337 0.124; 0.11 0.9; 0.9

EB-145-P-D5 0.061–0.705 (26) 0.02–0.26 (28) 0.8–2.4 (15)

0.469; 0.491 0.157; 0.16 1.17; 1.1

Halstead recharge site

SMW-H4 0.061–0.399 (27) 0.02–0.13 (27) 0.7–1.5 (19)

0.285; 0.307 0.093; 0.1 1.01; 0.9

SMW-H14 0.184–0.644 (27) 0.01–0.21 (28) 0.8–1.5 (20)

0.405; 0.429 0.128; 0.14 1.03; 1

DMW-H1 0.153–0.552 (27) 0.05–0.18 (27) 0.4–1.6 (19)

0.398; 0.399 0.13; 0.13 1.05; 1.3

DMW-H13 0.061–0.399 (27) 0.01–0.13 (28) 0.4–1.5 (20)

0.191; 0.153 0.06; 0.05 0.98; 1.2

Sedgwick recharge site

Treated stream water 0.031–0.92 (15) 0.01–0.3 (15) 0.5–6.8 (13)

0.486; 0.429 0.159; 0.14 4.62; 5

SMW-S11 0.061–0.215 (22) 0.01–0.07 (23) 0.5–3.6 (15)

0.139; 0.138 0.044; 0.04 1.32; 0.8

SMW-S13 0.061–0.245 (20) <0.01–0.08 (22) 0.4–8.2 (15)

0.146; 0.153 0.045*; 0.04 1.13; 0.6

DMW-S10 0.031–0.153 (15) <0.01–0.05 (22) 0.3–0.6 (14)

0.082; 0.061 0.021*; 0.02 0.407; 0.4

DMW-S14 0.031–0.153 (14) <0.01–0.05 (20) 0.4–0.6 (13)

0.07; 0.061 0.018*; 0.02 0.431; 0.4
Appendix 89

Table A–4. Summary of major-ion and nutrient concentrations in water samples collected as part of the Equus Beds Groundwater Recharge Project, 1995–2005.—Continued[mg/L, milligrams per liter; --, not determined; DWA, Drinking-Water Advisory; SDWR, Secondary Drinking-Water Regulation; <, less than; MCL, Maximum Contaminant Level; NA, not analyzed. The first set of numbers under each heading, for example 99–3,350, indicates the range in concentration. The number in parentheses () indicates the number of samples collected. The numbers below indicate the average followed by the median. Asterisk * is value estimated 

by using a log-probability regression to predict the values of data below the reporting level.]

Data-collection site

(fig. 6)

Calcium

(mg/L)

Magnesium

(mg/L)

Potassium

(mg/L)

Sodium

(mg/L)

Bicarbonate

(mg/L)

Carbonate

(mg/L)

Bromide

(mg/L)

Chloride

(mg/L)

Fluoride

(mg/L)

Drinking-water criteria -- -- -- 20 (DWA) -- -- -- 250 (SDWR) 2 (SDWR)

Reporting level 0.03 0.05 0.07 0.05 2.0 1.0 0.03 5.0 0.02

Background wells

EB-142-A3 71.3–75.8 (3) 11.2–11.9 (3) 3.41–3.63 (3) 42.2–45.9 (3) 240–240 (3) --–0 (3) <0.02–0.1 (3) 30–30 (3) 0.31–0.33 (3)

--; -- --; -- --; -- --; -- --; -- --; -- --; -- --; -- --; --

Sedgwick well 67.4–87.6 (45) 10.8–14.7 (45) 2.8–3.67 (45) 39.3–49 (45) 220–340 (45) 0–1 (45) 0.1–0.3 (28) 22–30 (45) 0.02–0.47 (28)

78.9; 79.9 13; 13.3 3.34; 3.31 44; 44 249; 250 0.022; 0 0.107; 0.1 25.8; 25.1 0.37; 0.39

City well-Sedgwick --–87.5 (1) --–16.2 (1) --–2.42 (1) --–72 (1) --–350 (1) --–0 (1) --–0.1 (1) --–34.8 (1) --–0.31 (1)

--; -- --; -- --; -- --; -- --; -- --; -- --; -- --; -- --; --

TH-02-95 90.3–101 (25) 9.23–10.9 (25) 1.85–2.27 (25) 35.8–44.3 (25) 340–380 (25) 0–1 (25) <0.02–0.1 (20) 24–32.3 (25) 0.07–0.31 (20)

97.3; 97.8 10.2; 10.2 2.1; 2.12 40.2; 39.9 355; 350 0.04; 0 0.100*; 0.1 28.2; 28 0.17; 0.17

TH-06-95 71.9–90.8 (27) 6.81–8.45 (27) 1.55–2.3 (27) 19.9–32.5 (27) 250–290 (27) 0–1 (27) <0.02–0.5 (22) 5–12 (27) 0.08–0.24 (22)

84.2; 84.7 7.99; 8.09 1.83; 1.83 22.6; 21.8 272; 270 0.037; 0 0.117*; 0.1 7.67; 7 0.17; 0.17

TH-10-95 44.8–63.6 (27) 4.37–6.4 (27) 1.37–1.87 (27) 17.8–21.9 (27) 210–390 (27) --–0 (27) <0.02–0.3 (22) <5–37 (27) 0.16–0.38 (22)

52.7; 52.9 5.19; 5.18 1.72; 1.72 20.4; 20.4 231; 220 --; -- --; <0.03 5.089*; <5 0.3; 0.29

TH-12-95 --–98.5 (1) --–15 (1) --–2.57 (1) --–54.4 (1) --–280 (1) --–0 (1) --–0.1 (1) --–18 (1) --–0.27 (1)

--; -- --; -- --; -- --; -- --; -- --; -- --; -- --; -- --; --

TH-08-A1 62.2–73.3 (7) 9.77–12.5 (7) 2.38–5.67 (7) 54.9–71.6 (7) 280–300 (7) --–0 (7) 0.1–0.1 (5) 30–44 (7) 0.28–0.38 (5)

67.8; 68 11.4; 11.4 2.9; 2.42 64.3; 64 294; 300 --; -- --; -- 37; 37 --; --

TH-08-A2 73.3–115 (10) 12.1–18.3 (10) 2.69–3.41 (10) 48.5–73.8 (10) 320–360 (10) <1–<1 (10) <0.03–0.1 (3) 25–65 (10) <0.02–0.41 (3)

90.8; 92.5 14.2; 14.2 2.88; 2.86 62.8; 61.2 342; 345 --; <1 --; -- 43.9; 44 --; --

TH-08-A3 53.5–75 (23) 10.2–13.8 (23) 1.99–2.51 (23) 58.7–90.7 (23) 290–350 (23) --–0 (23) 0–0.1 (20) 16–47 (23) 0.22–0.57 (20)

59.1; 58 11.2; 10.9 2.3; 2.31 69.1; 66.7 306; 300 --; -- 0.095; 0.1 22.7; 20 0.4; 0.42

TH-08-A4 --–55.8 (1) --–10.9 (1) --–2.12 (1) --–59.4 (1) --–280 (1) --–0 (1) --–0.1 (1) --–14 (1) --–0.38 (1)

--; -- --; -- --; -- --; -- --; -- --; -- --; -- --; -- --; --

TH-08-A5 57.9–79 (12) 9.91–14.4 (12) 2.65–4.8 (12) 31.3–73.7 (12) 250–330 (12) --–0 (12) 0.1–0.1 (12) 9–21 (12) 0.14–0.46 (12)

65.1; 64 12.1; 12.1 3.44; 3.24 56.7; 62.6 306; 325 --; -- 0.1; 0.1 16; 17 0.32; 0.36

Alta Mills 103–117 (23) 13.9–15.7 (23) 2.06–2.38 (23) 40–53.7 (23) 220–410 (23) --–0 (23) <0.3–0.2 (18) 5–21.9 (23) 0.09–0.31 (18)

110; 111 14.9; 15 2.19; 2.17 45.4; 44.7 374; 380 --; -- 0.106*; 0.1 16.8; 18 0.22; 0.23

Aquifer storage and recovery prototype wells

DW-TW-01 42.3–45 (7) 5.6–6.1 (7) 2.11–2.27 (7) 33.7–36.6 (7) 210–220 (7) --–0 (7) <0.03–<0.03 (6) <5–11 (7) 0.21–0.34 (6)

43.2; 43 5.81; 5.83 2.18; 2.16 34.7; 34.4 217; 220 --; -- --; -- 6.645*; 6 0.27; 0.26

DW-TW-02 40.3–44 (7) 5.8–6.53 (7) 1.99–2.23 (7) 31–34.7 (7) 210–220 (7) --–0 (7) <0.03–0.1 (6) 5–8.7 (7) 0.13–0.3 (6)

41.9; 41.8 6.14; 6.16 2.09; 2.09 32.7; 32.3 214; 210 --; -- --; -- 6.76; 6 0.26; 0.29

DW-TW-03 42.5–44.5 (7) 5.5–6.04 (7) 1.94–2.13 (7) 30.7–33.7 (7) 210–220 (7) --–0 (7) <0.03–0.1 (6) 5.6–11 (7) 0.15–0.56 (6)

43.2; 43.2 5.73; 5.73 2.04; 2.03 31.8; 31.5 213; 210 --; -- --; -- 6.87; 6 0.29; 0.25

DW-TW-04 43.4–45.7 (7) 5.19–5.85 (7) 1.93–2.15 (7) 30.1–33.1 (7) 200–220 (7) --–0 (7) <0.03–0.1 (6) 6–9.8 (7) 0.12–0.25 (6)

44.5; 44.6 5.52; 5.55 2.04; 2.03 31.2; 31.2 214; 220 --; -- --; -- 7.14; 6 0.22; 0.24

DW-TW-05 44.8–49 (7) 4.63–5.18 (7) 1.99–2.14 (7) 29.7–33.1 (7) 220–220 (7) --–0 (7) <0.03–0.3 (7) 5.6–8.3 (7) 0.11–0.29 (7)

46.4; 46.1 4.88; 4.86 2.05; 2.05 30.9; 30.2 220; 220 --; -- --; <0.03 6.2; 6 0.22; 0.24

DW-TW-06 43.2–48.2 (7) 5.18–6 (7) 1.84–1.96 (7) 28.2–32.4 (7) 200–220 (7) --–0 (7) <0.03–<0.03 (7) 5–9 (7) 0.12–0.28 (7)

44.9; 44.2 5.56; 5.53 1.9; 1.9 29.8; 29.3 214; 220 --; -- --; -- 5.9; 5.6 0.23; 0.25

DW-TW-07 44.8–69.6 (7) 5.69–15.4 (7) 1.88–2.36 (7) 26.7–40.4 (7) 210–220 (7) --–0 (7) <0.03–0.1 (7) 5.1–13 (7) <0.1–0.29 (7)

51; 48.3 7.7; 6.23 2; 1.97 30.6; 28.9 216; 220 --; -- --; <0.03 7.33; 6 0.254*; 0.25

DW-TW-08 46.8–49 (4) 4.7–5.04 (4) 1.67–1.77 (4) 28.8–30.1 (4) 210–230 (4) --–0 (4) <0.03–<0.03 (4) 5–7.8 (4) 0.22–0.31 (4)

--; -- --; -- --; -- --; -- --; -- --; -- --; -- --; -- --; --

DW-TW-09 45.1–46.2 (4) 5.33–5.71 (4) 1.81–1.87 (4) 29–30 (4) 220–230 (4) --–0 (4) <0.03–<0.03 (4) <5–7.1 (4) 0.25–0.31 (4)

--; -- --; -- --; -- --; -- --; -- --; -- --; -- --; -- --; --

RRW-01 37.1–48.8 (7) 3.76–4.51 (7) 1.44–1.98 (7) 14.9–19.7 (7) 160–190 (7) --–0 (7) <0.03–<0.03 (6) <5–6 (7) 0.11–0.29 (6)

41.1; 39.2 4.08; 4.12 1.75; 1.82 17.4; 17.5 173; 170 --; -- --; -- 5.051*; 5 0.17; 0.15

RRW-02 41.7–47 (7) 5.43–6.26 (7) 2.37–2.58 (7) 30.1–44.4 (7) 210–230 (7) --–0 (7) <0.03–0.1 (7) 6.8–12 (7) 0.23–0.47 (7)

44.7; 45.3 5.87; 5.89 2.44; 2.41 33.7; 31 220; 220 --; -- --; <0.03 8.16; 7.7 0.33; 0.32

RRW-03 43.3–49.3 (5) 6.47–7.78 (5) 2.6–2.98 (5) 32–36.1 (5) 160–180 (5) --–0 (5) 0.1–0.5 (5) 31–57 (5) 0.17–0.3 (5)

--; -- --; -- --; -- --; -- --; -- --; -- --; -- --; -- --; --
90 Water Quality in the Equus Beds Aquifer and the Little Arkansas River, South-Central Kansas Table A–4. Summary of major-ion and nutrient concentrations in water samples collected as part of the Equus Beds Groundwater Recharge Project, 1995–2005.—Continued [mg/L, milligrams per liter; --, not determined; DWA, Drinking-Water Advisory; SDWR, Secondary Drinking-Water Regulation; <, less than; MCL, Maximum Contaminant Level; NA, not analyzed. The first set of numbers under each heading, for example 99–3,350, indicates the range in concentration. The number in parentheses () indicates the number of samples collected. The numbers below indicate the average followed by the median. Asterisk * is value estimated by using a log-probability regression to predict the values of data below the reporting level.] Data-collection site (fig. 6) Sulfate (mg/L) Ammonia as nitrogen (mg/L) Nitrate as nitrogen, dissolved (mg/L) Nitrate as nitrogen, total (mg/L) Nitrite plus nitrate as nitrogen, dissolved (mg/L) Nitrite plus nitrate as nitrogen, total (mg/L) Nitrite as nitrogen, dissolved (mg/L) Nitrite as nitrogen, total (mg/L) Phosphorus, total (mg/L) Drinking-water criteria 250 (SDWR) -- 10 (MCL) 10 (MCL) 10 (MCL) 10 (MCL) 1 (MCL) 1 (MCL) -- Reporting level 5.0 0.03 0.01 0.01 0.02 0.02 0.02 0.02 0.01 Background wells EB-142-A3 77–86 (3) 0.018–0.04 (3) <0.01–<0.01 (3) --–<0.01 (1) <0.02–<0.02 (3) --–<0.02 (1) <0.01–<0.01 (3) --–<0.01 (1) --–0.07 (1) --; -- --; -- --; -- --; -- --; -- --; -- --; -- --; -- --; -- Sedgwick well 76–137 (45) <0.01–0.01 (27) <0.01–0.38 (26) --–<0.01 (1) <0.02–0.38 (45) <0.02–0.03 (3) 17.6–21.3 (27) <0.01–<0.01 (3) NA 99.9; 103 --; <0.02 <0.01; <0.01 --; -- 0.022*; <0.02 --; -- 19.7; 19.7 --; -- NA City well-Sedgwick --–74.5 (1) --–0.184 (1) NA NA --–<0.02 (1) --–<0.02 (1) --–<0.01 (1) --–<0.01 (1) --–0.07 (1) --; -- --; -- NA NA --; -- --; -- --; -- --; -- --; -- TH-02-95 5–52 (25) <0.03–0.35 (25) <0.01–0.01 (19) NA <0.02–0.02 (25) --–<0.02 (1) <0.01–<0.02 (20) --–<0.01 (1) --–0.09 (1) 36.9; 39 0.080*; 0.068 --; <0.01 NA --; <0.02 --; -- --; <0.02 --; -- --; -- TH-06-95 10–64.5 (27) 0.03–0.56 (27) <0.01–0.06 (21) NA <0.02–0.07 (27) <0.02–0.05 (2) <0.01–0.01 (22) <0.01–<0.01 (2) 0.17–0.19 (2) 54.4; 56 0.119; 0.08 --; <0.01 NA --; <0.02 --; -- --; <0.02 --; -- --; -- TH-10-95 <5–14 (27) 0.072–2.21 (27) <0.01–0.11 (21) NA <0.02–0.11 (27) --–<0.02 (1) <0.01–<0.02 (22) --–<0.01 (1) --–0.31 (1) 9.595*; 9.5 0.365; 0.24 0.026*; <0.01 NA 0.025*; <0.02 --; -- --; <0.02 --; -- --; -- TH-12-95 --–186 (1) --–0.055 (1) NA NA --–<0.02 (1) --–<0.02 (1) --–<0.01 (1) --–<0.01 (1) --–0.08 (1) --; -- --; -- NA NA --; -- --; -- --; -- --; -- --; -- TH-08-A1 44–64 (7) 0.108–0.702 (7) 0.01–2.61 (5) --–0.18 (1) <0.01–2.61 (7) --–0.18 (1) <0.01–<0.01 (5) --–<0.01 (1) --–0.23 (1) 53.3; 53 0.199; 0.115 --; -- --; -- 0.652*; 0.23 --; -- --; -- --; -- --; -- TH-08-A2 41–89 (10) 0.029–0.207 (10) <0.01–0.11 (3) --–<0.01 (1) <0.02–0.17 (10) --–<0.02 (1) <0.01–<0.02 (3) --–<0.01 (1) --–0.14 (1) 60.8; 60.7 0.093; 0.068 --; -- --; -- 0.062*; 0.01 --; -- --; -- --; -- --; -- TH-08-A3 49–73 (23) 0.05–1.76 (23) <0.01–0.03 (20) NA <0.02–0.03 (23) NA <0.01–<0.02 (20) NA NA 55.8; 54 0.332; 0.28 0.007*; <0.01 NA 0.012*; <0.02 NA --; <0.02 NA NA TH-08-A4 --–45 (1) --–0.32 (1) --–0.01 (1) NA --–0.01 (1) NA --–<0.02 (1) NA NA --; -- --; -- --; -- NA --; -- NA --; -- NA NA TH-08-A5 <5–70 (12) 0.04–0.22 (12) <0.01–1.14 (12) NA <0.02–1.14 (12) NA <0.02–<0.02 (12) NA NA 55.804*; 62 0.125; 0.12 0.211*; <0.01 NA 0.211*; <0.02 NA --; <0.02 NA NA Alta Mills 6–68 (23) <0.03–0.23 (23) 3.59–11.5 (18) NA <0.02–11.7 (23) NA <0.02–6.76 (18) NA NA 50.4; 52 0.043*; <0.03 6.8; 6.54 NA 7.284*; 6.65 NA --; <0.02 NA NA Aquifer storage and recovery prototype wells DW-TW-01 8.3–19 (7) 0.09–0.14 (7) <0.01–0.2 (6) NA <0.02–0.2 (7) NA <0.02–<0.02 (6) NA NA 15.7; 16.7 0.119; 0.12 --; <0.01 NA --; <0.02 NA --; <0.02 NA NA DW-TW-02 13–20 (7) 0.12–0.16 (7) <0.01–0.03 (6) NA <0.02–0.03 (7) NA <0.02–<0.02 (6) NA NA 15.2; 15 0.14; 0.14 --; <0.01 NA --; <0.02 NA --; <0.02 NA NA DW-TW-03 11.8–19.1 (7) 0.15–0.19 (7) <0.01–0.07 (6) NA <0.02–0.07 (7) NA <0.02–<0.02 (6) NA NA 15.2; 15.1 0.164; 0.16 --; 0.02 NA --; 0.02 NA --; <0.02 NA NA DW-TW-04 12–17 (7) 0.12–0.18 (7) <0.01–0.05 (6) NA <0.02–0.05 (7) NA <0.02–<0.02 (6) NA NA 14.9; 14 0.154; 0.16 --; <0.01 NA --; <0.02 NA --; <0.02 NA NA DW-TW-05 12.8–18 (7) 0.14–0.2 (7) <0.01–0.05 (7) NA <0.02–0.05 (7) NA <0.02–<0.02 (7) NA NA

15.5; 16 0.164; 0.16 --; <0.01 NA --; <0.02 NA --; <0.02 NA NA

DW-TW-06 11–15.3 (7) 0.18–0.23 (7) <0.01–0.05 (7) NA <0.02–0.05 (7) NA <0.02–<0.02 (7) NA NA

13.2; 13.5 0.206; 0.21 --; <0.01 NA --; <0.02 NA --; <0.02 NA NA

DW-TW-07 9.7–135 (7) 0.19–0.26 (7) <0.01–0.04 (7) NA <0.02–0.04 (7) NA <0.02–<0.02 (7) NA NA

35.5; 14.6 0.209; 0.2 --; <0.01 NA --; <0.02 NA --; <0.02 NA NA

DW-TW-08 12.6–18.4 (4) 0.16–0.2 (4) <0.01–0.04 (4) NA <0.02–0.04 (4) NA <0.02–<0.02 (4) NA NA

--; -- --; -- --; -- NA --; -- NA --; -- NA NA

DW-TW-09 12.4–15.4 (4) 0.19–0.28 (4) <0.01–0.12 (4) NA <0.02–0.12 (4) NA <0.02–<0.02 (4) NA NA

--; -- --; -- --; -- NA --; -- NA --; -- NA NA

RRW-01 7.1–16.1 (7) 0.03–0.07 (7) <0.01–1.07 (6) NA <0.02–1.07 (7) NA <0.02–0.02 (6) NA NA

10.2; 9.4 0.051; 0.06 0.372*; 0.19 NA 0.375*; 0.3 NA --; <0.02 NA NA

RRW-02 17–22 (7) 0.12–0.15 (7) <0.01–0.05 (7) NA <0.02–0.05 (7) NA <0.02–<0.02 (7) NA NA

18.4; 17.8 0.134; 0.14 --; <0.01 NA --; <0.02 NA --; <0.02 NA NA

RRW-03 22–30 (5) 0.09–0.15 (5) <0.01–0.01 (5) NA <0.02–0.01 (5) NA <0.02–<0.02 (5) NA NA

--; -- --; -- --; -- NA --; -- NA --; -- NA NA
Appendix 91

Table A–4. Summary of major-ion and nutrient concentrations in water samples collected as part of the Equus

Beds Groundwater Recharge Project, 1995–2005.—Continued

[mg/L, milligrams per liter; --, not determined; DWA, Drinking-Water Advisory; SDWR, Secondary Drinking-Water Regulation; <, less than; MCL, Maximum Contaminant Level; NA, not analyzed. The first set of numbers under each heading, for example 99–3,350, indicates the range in concentration. The number in parentheses () indicates the number of samples collected. The numbers below indicate the average followed by the median. Asterisk 

* is value estimated by using a log-probability regression to predict the values of data below the reporting level.]

Data-collection site

(fig. 6)

Orthophosphate 

(mg/L)

Orthophosphate as phosphorous 

(mg/L)

Organic carbon, total 

(mg/L)

Drinking-water criteria -- -- --

Reporting level 0.01 0.01 0.2

Background wells

EB-142-A3 NA <0.01–<0.01 (3) 0.5–0.7 (3)

NA --; -- --; --

Sedgwick well 0.061–0.153 (14) <0.03–0.15 (45) 0.6–1.3 (15)

0.107; 0.123 0.043*; 0.033 0.753; 0.6

City well-Sedgwick --–0.061 (1) --–0.02 (1) --–1.2 (1)

--; -- --; -- --; --

TH-02-95 0.031–0.245 (10) <0.01–0.08 (20) 0.5–0.8 (7)

0.104; 0.092 0.021*; 0.01 0.643; 0.6

TH-06-95 0.123–0.583 (14) <0.01–0.19 (22) 0.5–1 (8)

0.3; 0.292 0.070*; 0.06 0.775; 0.75

TH-10-95 0.368–0.767 (21) 0.12–0.25 (22) 0.7–1.1 (7)

0.57; 0.583 0.185; 0.185 0.857; 0.8

TH-12-95 NA --–<0.02 (1) --–1.3 (1)

NA --; -- --; --

TH-08-A1 0.276–0.736 (5) 0.09–0.24 (5) 0.6–1.9 (5)

--; -- --; -- --; --

TH-08-A2 0.245–0.337 (2) <0.01–0.11 (3) 0.7–0.8 (3)

--; -- --; -- --; --

TH-08-A3 0.215–0.644 (19) 0.07–0.21 (20) 0.7–1.1 (7)

0.405; 0.399 0.132; 0.125 0.843; 0.8

TH-08-A4 --–0.521 (1) --–0.17 (1) --–0.7 (1)

--; -- --; -- --; --

TH-08-A5 0.153–0.767 (11) 0.05–0.25 (12) 0.5–1.2 (3)

0.463; 0.46 0.156; 0.15 --; --

Alta Mills 0.307–0.797 (17) 0.1–0.26 (18) 0.7–1.1 (6)

0.638; 0.705 0.209; 0.23 0.95; 0.95

Aquifer storage and recovery prototype wells

DW-TW-01 0.276–0.429 (6) 0.09–0.14 (6) 0.5–0.5 (6)

0.378; 0.399 0.123; 0.13 0.5; 0.5

DW-TW-02 0.368–0.399 (6) 0.12–0.13 (6) 0.5–0.5 (6)

0.389; 0.399 0.127; 0.13 0.5; 0.5

DW-TW-03 0.368–0.552 (6) 0.12–0.18 (6) 0.4–0.5 (6)

0.429; 0.399 0.14; 0.13 0.483; 0.5

DW-TW-04 0.337–0.399 (6) 0.11–0.13 (6) 0.4–0.5 (6)

0.368; 0.368 0.12; 0.12 0.433; 0.4

DW-TW-05 0.46–0.675 (6) <0.01–0.22 (7) 0.4–0.5 (6)

0.572; 0.567 0.179*; 0.18 0.45; 0.45

DW-TW-06 0.215–0.583 (7) 0.07–0.19 (7) 0.4–0.6 (6)

0.416; 0.429 0.136; 0.14 0.517; 0.5

DW-TW-07 0.276–0.521 (7) 0.09–0.17 (7) 0.5–0.5 (6)

0.416; 0.429 0.136; 0.14 0.5; 0.5

DW-TW-08 0.521–0.675 (4) 0.17–0.22 (4) 0.5–0.6 (4)

--; -- --; -- --; --

DW-TW-09 0.552–0.797 (4) 0.18–0.26 (4) 0.5–0.6 (4)

--; -- --; -- --; --

RRW-01 0.153–0.399 (6) 0.05–0.13 (6) 0.3–0.4 (6)

0.261; 0.245 0.085; 0.08 0.333; 0.3

RRW-02 0.767–4.81 (7) 0.25–1.57 (7) 0.4–0.8 (6)

1.703; 1.07 0.556; 0.35 0.533; 0.5

RRW-03 0.429–0.521 (5) 0.14–0.17 (5) 0.3–0.4 (4)

--; -- --; -- --; --
92 Water Quality in the Equus Beds Aquifer and the Little Arkansas River, South-Central Kansas Table A–4. Summary of major-ion and nutrient concentrations in water samples collected as part of the Equus Beds Groundwater Recharge Project, 1995–2005.—Continued [mg/L, milligrams per liter; --, not determined; DWA, Drinking-Water Advisory; SDWR, Secondary Drinking-Water Regulation; <, less than; MCL, Maximum Contaminant Level; NA, not analyzed. The first set of numbers under each heading, for example 99–3,350, indicates the range in concentration. The number in parentheses () indicates the number of samples collected. The numbers below indicate the average followed by the median. Asterisk * is value estimated by using a log-probability regression to predict the values of data below the reporting level.] Data-collection site (fig. 6) Calcium (mg/L) Magnesium (mg/L) Potassium (mg/L) Sodium (mg/L) Bicarbonate (mg/L) Carbonate (mg/L) Bromide (mg/L) Chloride (mg/L) Fluoride (mg/L) Drinking-water criteria -- -- -- 20 (DWA) -- -- -- 250 (SDWR) 2 (SDWR) Reporting level 0.03 0.05 0.07 0.05 2.0 1.0 0.03 5.0 0.02 Shallow index wells IW-01A 7.41–12.5 (7) 1.85–3.14 (7) 1.06–1.31 (7) 12.5–15.6 (7) 39–69 (7) --–0 (7) <0.03–0.1 (6) <5–11 (7) 0.07–0.32 (6) 10.5; 10.5 2.58; 2.61 1.19; 1.2 14.1; 13.8 51.3; 50 --; -- --; -- 7.658*; 7.1 0.16; 0.14 IW-02A 11.7–16.3 (7) 2.63–3.02 (7) 2.16–2.63 (7) 16–19 (7) 34–48 (7) --–0 (7) <0.03–<0.03 (6) 5–14 (7) 0.07–0.26 (6) 13; 12.6 2.76; 2.76 2.33; 2.36 17.4; 17 39.9; 38 --; -- --; <0.03 7.66; 6 0.13; 0.11 IW-03A 40.3–57 (7) 7.35–10.1 (7) 1.32–1.52 (7) 49–57.9 (7) 250–280 (7) --–0 (7) <0.03–0.1 (6) 7.3–28 (7) 0.25–0.43 (6) 48.4; 47.2 8.9; 8.99 1.39; 1.37 53.6; 53.8 266; 260 --; -- --; -- 18.6; 20 0.32; 0.3 IW-04A 27.9–42.2 (7) 5.76–10.1 (7) 8.8–12.7 (7) 50.5–71.5 (7) 160–270 (7) --–0 (7) 0.1–0.1 (6) 53–66 (7) 0.04–0.2 (6) 34.9; 32.3 7.65; 7.76 9.96; 9.65 64.2; 67.9 221; 220 --; -- 0.1; 0.1 57.7; 56 0.12; 0.11 IW-05A 35.2–41.2 (7) 6.33–7.87 (7) 3.06–3.48 (7) 26.2–31.8 (7) 93–110 (7) --–0 (7) <0.03–0.2 (7) 34–54 (7) 0.1–0.26 (7) 38.5; 38.3 7.09; 6.94 3.24; 3.25 28.9; 28 100; 100 --; -- 0.154*; 0.2 42.6; 41.2 0.16; 0.14 IW-06A 58.2–66.9 (8) 9.7–11.8 (8) 1.85–2.25 (8) 38.6–49.1 (8) 98–120 (7) --–0 (7) 0.2–0.3 (7) 40–59 (8) 0.09–0.24 (8) 61.7; 61 10.6; 10.4 2.06; 2.05 42.4; 39.9 110; 110 --; -- 0.271; 0.3 45.9; 42.3 0.16; 0.16 IW-07A 41.8–44.6 (7) 5.01–5.3 (7) 1.7–1.95 (7) 28.2–32.2 (7) 200–210 (7) --–0 (7) <0.03–0.1 (7) 7–11 (7) 0.25–0.38 (7) 43.2; 43 5.14; 5.15 1.85; 1.87 29.7; 29 203; 200 --; -- --; -- 8.69; 8 0.33; 0.34 IW-08A 144–161 (7) 31.2–37.2 (7) 5.21–6.54 (7) 137–191 (7) 280–340 (7) --–0 (7) 0.4–0.6 (6) 136–154 (7) 0.29–0.56 (6) 154; 155 34.7; 35 5.68; 5.58 157; 154 310; 310 --; -- 0.5; 0.5 146; 147 0.4; 0.42 IW-09A 63.5–69.9 (7) 12.1–12.9 (7) 3.45–3.82 (7) 30.8–45.1 (7) 130–180 (7) --–0 (7) 0.1–0.2 (7) 10.5–19 (7) 0.26–0.51 (7) 66.7; 65.5 12.5; 12.5 3.61; 3.55 36.7; 34.2 154; 150 --; -- 0.114; 0.1 15.5; 16 0.42; 0.47 IW-10A 43–52.6 (7) 9.09–11.3 (7) 3.39–3.87 (7) 29.1–37.4 (7) 110–120 (7) --–0 (7) 0.1–0.3 (7) 39–61 (7) 0.15–0.25 (7) 47.4; 47.7 10; 9.93 3.58; 3.52 32.6; 33.2 113; 110 --; -- 0.214; 0.2 52.3; 53 0.18; 0.18 IW-11A-2 38.9–57.2 (7) 5.37–7.6 (7) 1.83–2.16 (7) 39.1–51.9 (7) 230–310 (7) --–0 (7) <0.03–0.1 (7) 6–19 (7) 0.25–0.39 (7) 44.7; 43.3 5.98; 5.78 2.01; 2.04 43; 41.3 256; 250 --; -- --; <0.03 9.57; 8 0.3; 0.3 IW-12A 58.2–95.9 (9) 10.5–17.2 (9) 1.16–2.02 (9) 33.2–70.6 (9) 220–350 (8) --–0 (8) 0–0.2 (8) 6.3–36 (9) 0.18–0.3 (9) 73.7; 75.8 13.3; 13.3 1.49; 1.4 50.5; 44.9 291; 290 --; -- 0.1; 0.1 18; 19 0.24; 0.24 IW-13A 112–129 (8) 24.9–28.8 (8) 3.48–4.51 (8) 115–141 (8) 330–360 (7) --–0 (7) 0.1–0.2 (7) 114–155 (8) 0.4–0.62 (8) 116; 114 26.2; 26.1 4.08; 4.17 127; 128 340; 340 --; -- 0.143; 0.1 131; 128 0.53; 0.52 IW-14A 43.5–131 (8) 8.71–26.5 (8) 3.48–4.67 (8) 80.9–137 (8) 74–270 (8) --–0 (8) 0.1–0.1 (8) 43–118 (8) 0.55–0.92 (8) 69.2; 61.8 14.6; 13.4 3.84; 3.73 94.1; 87.3 153; 145 --; -- 0.1; 0.1 66.4; 58.5 0.67; 0.65 IW-15A 170–208 (7) 31.6–39.5 (7) 4.63–5.17 (7) 80.6–89.2 (7) 250–290 (7) <1–<1 (7) 0.1–0.2 (7) 61–102 (7) 0.05–0.42 (7) 184; 183 34; 33.4 4.88; 4.91 84.6; 83.7 269; 270 --; <1 0.157; 0.2 72.7; 68 0.31; 0.34 IW-16A 111–124 (7) 16.9–18.7 (7) 3.74–4 (7) 38.9–42.6 (7) 170–200 (7) <1–<1 (7) 0–0.1 (7) 14–17 (7) 0.08–0.25 (7) 117; 116 17.7; 17.6 3.87; 3.87 41.1; 41.6 181; 180 --; <1 0.086; 0.1 15.7; 16 0.18; 0.19 IW-17A 100–109 (7) 15.5–16.9 (7) 3.13–3.27 (7) 78.4–92.7 (7) 300–440 (7) --–0 (7) <0.03–0.1 (7) 8–11 (7) 0.05–0.41 (7) 104; 103 16; 16 3.21; 3.22 85.5; 84.5 404; 420 --; -- 0.100*; 0.1 9.57; 9 0.29; 0.32 IW-18A 132–151 (7) 21.2–24.3 (7) 4.47–4.83 (7) 104–127 (7) 360–370 (7) --–0 (7) 0.2–0.2 (7) 116–151 (7) 0.41–0.54 (7) 138; 136 22.5; 22.3 4.61; 4.57 114; 113 366; 370 --; -- 0.2; 0.2 140; 143 0.5; 0.51 IW-19A 152–177 (7) 30.4–38.6 (7) 5.17–6.34 (7) 138–169 (7) 370–450 (7) <1–<1 (7) 0.1–0.3 (7) 134–178 (7) 0.52–0.74 (7)

163; 162 34.2; 34.4 5.91; 5.94 158; 161 417; 420 --; <1 0.2; 0.2 153; 148 0.62; 0.6

IW-20A 187–219 (7) 35–41.4 (7) 5.16–5.67 (7) 154–179 (7) 210–220 (7) --–0 (7) 0.1–0.2 (7) 71–88 (7) 0.07–0.66 (7)

202; 204 39.5; 39.3 5.34; 5.34 168; 171 213; 210 --; -- 0.171; 0.2 81.7; 82 0.44; 0.56

IW-21A 110–146 (7) 20.4–26 (7) 3.66–4.67 (7) 55.7–72 (7) 210–280 (7) <1–<1 (7) 0.1–0.1 (7) 38–75 (7) 0.07–0.36 (7)

123; 118 22.5; 21.6 3.95; 3.79 63; 61.7 234; 230 --; <1 0.1; 0.1 51.9; 52 0.26; 0.27

IW-22A 110–130 (8) 15.9–19.8 (8) 2.81–3.61 (8) 50.7–63.5 (8) 340–370 (7) --–0 (7) 0.1–0.1 (7) 20–50 (8) 0.32–0.49 (8)

119; 117 18.1; 17.8 3.25; 3.3 56.4; 56.4 359; 360 --; -- 0.1; 0.1 27.8; 24.6 0.41; 0.42

IW-23A 57.8–71.6 (7) 11.9–14.6 (7) 2.27–2.55 (7) 67.9–79.1 (7) 300–370 (7) --–0 (7) 0.1–0.1 (7) 12–18 (7) 0.35–0.48 (7)

66.7; 67 13.5; 13.4 2.41; 2.44 72.9; 70.5 336; 330 --; -- 0.1; 0.1 15.3; 15 0.44; 0.45

IW-24A 97.8–108 (8) 16.7–18.9 (8) 3.06–3.54 (8) 65.2–74.9 (8) 280–290 (7) --–0 (7) 0.1–0.2 (7) 89–101 (8) 0.3–0.51 (8)

102; 101 17.8; 17.6 3.39; 3.46 70.9; 71.1 286; 290 --; -- 0.143; 0.1 97.4; 99.4 0.45; 0.49

IW-25A 93.2–103 (7) 13.3–17.7 (7) 3.4–5.84 (7) 69.2–87.8 (7) 300–350 (7) --–0 (7) 0.1–0.2 (7) 28–67.5 (7) 0.05–0.67 (7)

96.5; 95.1 14.2; 13.5 5.14; 5.31 80.2; 81.1 337; 340 --; -- 0.114; 0.1 54.2; 56 0.41; 0.44

IW-26A 77.6–98.2 (7) 13.5–17 (7) 3.42–4.27 (7) 39.1–48.1 (7) 310–370 (7) --–0 (7) <0.03–0.1 (7) 6–17 (7) 0.38–0.81 (7)

87.5; 86.8 15.5; 15.7 3.82; 3.9 44.3; 45 351; 360 --; -- --; <0.03 10.9; 10 0.57; 0.51
Appendix 93

Table A–4. Summary of major-ion and nutrient concentrations in water samples collected as part of the Equus Beds Groundwater Recharge Project, 1995–2005.—Continued[mg/L, milligrams per liter; --, not determined; DWA, Drinking-Water Advisory; SDWR, Secondary Drinking-Water Regulation; <, less than; MCL, Maximum Contaminant Level; NA, not analyzed. The first set of numbers under each heading, for example 99–3,350, indicates the range in concentration. The number in parentheses () indicates the number of samples collected. The numbers below indicate the average followed by the median. Asterisk * is value estimated 

by using a log-probability regression to predict the values of data below the reporting level.]

Data-collection site

(fig. 6)

Sulfate

(mg/L)

Ammonia as nitrogen

(mg/L)

Nitrate as nitrogen, 

dissolved 

(mg/L)

Nitrate as nitrogen,

total 

(mg/L)

Nitrite plus nitrate as 

nitrogen, dissolved 

(mg/L)

Nitrite plus nitrate 

as nitrogen, total 

(mg/L)

Nitrite as nitrogen, 

dissolved 

(mg/L)

Nitrite as nitrogen,

total 

(mg/L)

Phosphorus, 

total 

(mg/L)

Drinking-water criteria 250 (SDWR) -- 10 (MCL) 10 (MCL) 10 (MCL) 10 (MCL) 1 (MCL) 1 (MCL) --

Reporting level 5.0 0.03 0.01 0.01 0.02 0.02 0.02 0.02 0.01

Shallow index wells—Continued

IW-01A <5–22 (7) <0.03–0.66 (7) 0.08–2.04 (6) NA 0.08–2.04 (7) NA <0.02–<0.02 (6) NA NA

17.369*; 18 --; <0.03 1.08; 1.09 NA 1.06; 1 NA --; <0.02 NA NA

IW-02A 36.9–51 (7) <0.03–0.069 (7) 0.66–1.05 (6) NA 0.66–1.05 (7) NA <0.02–0.66 (6) NA NA

41.1; 39 --; <0.03 0.872; 0.915 NA 0.88; 0.93 NA --; <0.02 NA NA

IW-03A 12.6–42 (7) 0.1–0.18 (7) <0.01–0.07 (6) NA <0.02–0.07 (7) NA <0.02–<0.02 (6) NA NA

32.5; 36 0.137; 0.14 --; <0.01 NA --; <0.02 NA --; <0.02 NA NA

IW-04A 6–29 (7) 0.04–3.22 (7) <0.01–1.65 (6) NA <0.02–1.65 (7) NA <0.02–0.02 (6) NA NA

15.2; 11 1.01; 0.28 0.388*; 0.02 NA 0.409*; 0.03 NA --; <0.02 NA NA

IW-05A 25–39 (7) <0.03–0.07 (7) 0.12–6.61 (7) NA 0.19–6.61 (7) NA <0.02–3.52 (7) NA NA

29.9; 29 0.043*; 0.04 4.06; 4.15 NA 4.07; 4.15 NA --; <0.02 NA NA

IW-06A 38–55.5 (8) <0.03–0.06 (8) 17.2–23.8 (7) NA 17.2–23.8 (8) NA <0.008–<0.02 (8) NA --–0.11 (1)

46.1; 45.8 --; <0.04 20.9; 21.3 NA 21.2; 21.6 NA --; <0.02 NA --; --

IW-07A 13–20 (7) 0.14–0.24 (7) <0.01–0.08 (7) NA <0.02–0.08 (7) NA <0.02–0.01 (7) NA NA

15.6; 16 0.2; 0.2 --; 0.01 NA --; <0.02 NA --; <0.02 NA NA

IW-08A 315–515 (7) <0.03–0.208 (7) 2.26–6.22 (6) NA 2.26–6.22 (7) NA <0.02–<0.02 (6) NA NA

370; 359 --; 0.03 4.47; 4.6 NA 4.26; 3.87 NA --; <0.02 NA NA

IW-09A 79–139 (7) <0.03–0.06 (7) <0.01–13.2 (7) NA 0.06–13.3 (7) NA <0.02–0.06 (7) NA NA

109; 104 --; <0.03 7.79*; 6.96 NA 7.36; 6.96 NA --; 0.05 NA NA

IW-10A 31–48 (7) <0.03–0.06 (7) 3.73–8.46 (7) NA 3.73–8.46 (7) NA <0.02–<0.02 (7) NA NA

38.3; 38 --; <0.03 5.92; 5.29 NA 5.92; 5.29 NA --; <0.02 NA NA

IW-11A-2 <5–11 (7) 0.23–0.27 (7) <0.01–0.28 (7) NA <0.02–0.28 (7) NA <0.02–<0.02 (7) NA NA

8.895*; 9 0.246; 0.24 --; 0.02 NA --; 0.02 NA --; <0.02 NA NA

IW-12A 46–128 (9) <0.03–0.09 (9) 0.05–0.48 (8) NA 0.05–0.48 (9) NA <0.02–0.004 (9) NA --–0.11 (1)

74.1; 64 0.045*; 0.04 0.226; 0.185 NA 0.23; 0.23 NA --; <0.02 NA --; --

IW-13A 170–241 (8) 0.04–0.14 (8) <0.01–0.03 (7) NA <0.02–0.03 (8) NA <0.008–<0.02 (8) NA --–0.1 (1)

201; 200 0.065; 0.045 --; <0.01 NA --; <0.02 NA --; <0.02 NA --; --

IW-14A 161–341 (8) 0.04–0.12 (8) <0.01–0.01 (8) NA <0.02–0.01 (8) NA <0.02–<0.02 (8) NA NA

210; 197 0.069; 0.06 --; <0.01 NA --; <0.02 NA --; <0.02 NA NA

IW-15A 308–672 (7) 0.1–0.26 (7) <0.01–0.02 (7) NA <0.02–0.05 (7) NA <0.02–0.05 (7) NA NA

456; 425 0.151; 0.13 --; <0.01 NA --; <0.02 NA --; <0.02 NA NA

IW-16A 256–346 (7) 0.15–0.23 (7) <0.01–0.01 (7) NA <0.02–0.01 (7) NA <0.02–<0.02 (7) NA NA

288; 282 0.189; 0.19 --; <0.01 NA --; <0.02 NA --; <0.02 NA NA

IW-17A 126–153 (7) 0.05–0.17 (7) <0.01–0.08 (7) NA <0.02–0.08 (7) NA <0.02–<0.02 (7) NA NA

139; 136 0.123; 0.14 --; <0.01 NA --; <0.02 NA --; <0.02 NA NA

IW-18A 148–197 (7) <0.03–0.05 (7) 0.01–0.12 (7) NA <0.02–0.12 (7) NA <0.02–<0.02 (7) NA NA

170; 170 0.036*; 0.04 0.049; 0.04 NA 0.049*; 0.04 NA --; <0.02 NA NA

IW-19A 250–386 (7) 0.04–0.16 (7) <0.01–0.02 (7) NA <0.02–0.02 (7) NA <0.02–<0.02 (7) NA NA

317; 321 0.093; 0.08 --; <0.01 NA --; <0.02 NA --; <0.02 NA NA

IW-20A 264–760 (7) 0.1–0.28 (7) <0.01–0.04 (7) NA <0.02–0.06 (7) NA <0.02–0.06 (7) NA NA

620; 739 0.15; 0.13 --; <0.01 NA --; 0.01 NA --; <0.02 NA NA

IW-21A 244–324 (7) 0.06–0.11 (7) <0.01–0.06 (7) NA <0.02–0.06 (7) NA <0.02–<0.02 (7) NA NA

280; 284 0.087; 0.09 --; <0.01 NA --; <0.02 NA --; <0.02 NA NA

IW-22A 129–235 (8) 0.03–0.27 (8) <0.01–0.05 (7) NA <0.02–0.05 (8) NA <0.02–0.007 (8) NA --–0.06 (1)

163; 155 0.066; 0.04 --; <0.01 NA --; <0.02 NA --; <0.02 NA --; --

IW-23A 57–86 (7) 0.14–0.34 (7) <0.01–0.01 (7) NA <0.02–0.01 (7) NA <0.02–<0.02 (7) NA NA

72.1; 71 0.244; 0.25 --; <0.01 NA --; <0.02 NA --; <0.02 NA NA

IW-24A 57–77 (8) <0.03–0.06 (8) <0.01–8.96 (7) NA <0.02–8.96 (8) NA <0.008–<0.02 (8) NA --–0.03 (1)

66.5; 67.3 --; <0.03 7.62*; 7.51 NA 7.733*; 7.51 NA --; <0.02 NA --; --

IW-25A 66–130 (7) <0.03–0.06 (7) <0.01–3.95 (7) NA <0.02–3.95 (7) NA <0.02–<0.02 (7) NA NA

87.3; 80 --; 0.04 1.89*; 2.21 NA 1.898*; 2.21 NA --; <0.02 NA NA

IW-26A 30–64 (7) <0.03–0.05 (7) <0.01–6.12 (7) NA 2.07–6.12 (7) NA <0.02–2.07 (7) NA NA

48.7; 51.8 --; <0.03 3.84*; 3.75 NA 3.87; 3.75 NA --; <0.02 NA NA
94 Water Quality in the Equus Beds Aquifer and the Little Arkansas River, South-Central Kansas Table A–4. Summary of major-ion and nutrient concentrations in water samples collected as part of the Equus Beds Groundwater Recharge Project, 1995–2005.—Continued [mg/L, milligrams per liter; --, not determined; DWA, Drinking-Water Advisory; SDWR, Secondary Drinking-Water Regulation; <, less than; MCL, Maximum Contaminant Level; NA, not analyzed. The first set of numbers under each heading, for example 99–3,350, indicates the range in concentration. The number in parentheses () indicates the number of samples collected. The numbers below indicate the average followed by the median. Asterisk * is value estimated by using a log-probability regression to predict the values of data below the reporting level.] Data-collection site (fig. 6) Orthophosphate (mg/L) Orthophosphate as phosphorous (mg/L) Organic carbon, total (mg/L) Drinking-water criteria -- -- -- Reporting level 0.01 0.01 0.2 Shallow index wells—Continued IW-01A 0.184–0.644 (6) 0.06–0.21 (6) 0.8–1.2 (3) 0.296; 0.23 0.097; 0.075 --; -- IW-02A 0.123–0.399 (6) 0.04–0.13 (6) 0.8–1.6 (3) 0.225; 0.215 0.073; 0.07 --; -- IW-03A 0.368–0.951 (5) <0.01–0.31 (6) 1.1–1.6 (3) --; -- 0.204*; 0.19 --; -- IW-04A 0.123–6.84 (6) 0.04–2.23 (6) 3.9–8.6 (3) 2.55; 1.6 0.832; 0.52 --; -- IW-05A 0.092–0.276 (6) <0.01–0.09 (7) 0.4–1 (3) 0.183; 0.169 0.054*; 0.05 --; -- IW-06A 0.123–0.368 (7) <0.01–0.12 (8) 1–1.5 (4) 0.251; 0.276 0.075*; 0.06 --; -- IW-07A 0.491–0.859 (7) 0.16–0.28 (7) 0.6–1.1 (3) 0.666; 0.705 0.217; 0.23 --; -- IW-08A 0.092–0.215 (5) <0.01–0.07 (6) 1.6–2 (3) --; -- 0.045*; 0.04 --; -- IW-09A 0.215–0.736 (6) <0.01–0.24 (7) 0.6–1.3 (3) 0.378; 0.276 0.110*; 0.09 --; -- IW-10A 0.061–0.215 (6) <0.01–0.07 (7) 0.5–0.9 (3) 0.164; 0.184 0.048*; 0.06 --; -- IW-11A-2 0.245–0.552 (7) 0.08–0.18 (7) 0.8–1 (4) 0.429; 0.46 0.14; 0.15 --; -- IW-12A 0.092–0.491 (7) <0.01–0.16 (9) 0.5–1.3 (4) 0.27; 0.276 0.073*; 0.08 --; -- IW-13A 0.061–0.215 (4) <0.01–0.07 (8) 1–1.7 (5) --; -- --; <0.01 --; -- IW-14A 0.123–0.368 (7) <0.01–0.12 (8) 1.6–2.1 (4) 0.28; 0.307 0.085*; 0.09 --; -- IW-15A 0.031–0.613 (3) <0.01–0.2 (7) 1–1.8 (3) --; -- --; <0.01 --; -- IW-16A 0.061–0.276 (4) <0.01–0.09 (7) 0.7–1.4 (4) --; -- --; 0.02 --; -- IW-17A 0.031–0.613 (6) <0.01–0.2 (7) 0.6–1.2 (3) 0.215; 0.123 0.060*; 0.03 --; -- IW-18A --–0.061 (1) <0.01–0.02 (7) 0.8–1.5 (3) --; -- --; <0.01 --; --

IW-19A 0.092–0.153 (4) <0.01–0.05 (7) 0.9–1.6 (3)

--; -- --; 0.03 --; --

IW-20A 0.061–0.276 (4) <0.01–0.09 (7) 1–1.9 (3)

--; -- --; 0.02 --; --

IW-21A 0.031–0.245 (2) <0.01–0.08 (7) 1–1.8 (4)

--; -- --; <0.01 --; --

IW-22A 0.092–1.5 (7) <0.01–0.49 (8) 0.8–2.2 (4)

0.35; 0.156 0.101*; 0.05 --; --

IW-23A 0.031–0.521 (7) 0.01–0.17 (7) 0.8–1.6 (3)

0.294; 0.307 0.096; 0.1 --; --

IW-24A 0.092–0.123 (5) <0.01–0.04 (8) 0.5–2.7 (4)

--; -- 0.032*; 0.03 --; --

IW-25A 0.092–0.123 (5) <0.01–0.04 (7) 0.5–1.2 (3)

--; -- 0.026* ; 0.03 --; --

IW-26A 0.092–0.276 (7) 0.03–0.09 (7) 0.5–1.2 (3)

0.171; 0.153 0.056; 0.05 --; --
Appendix 95

Table A–4. Summary of major-ion and nutrient concentrations in water samples collected as part of the Equus Beds Groundwater Recharge Project, 1995–2005.—Continued[mg/L, milligrams per liter; --, not determined; DWA, Drinking-Water Advisory; SDWR, Secondary Drinking-Water Regulation; <, less than; MCL, Maximum Contaminant Level; NA, not analyzed. The first set of numbers under each heading, for example 99–3,350, indicates the range in concentration. The number in parentheses () indicates the number of samples collected. The numbers below indicate the average followed by the median. Asterisk * is value estimated 

by using a log-probability regression to predict the values of data below the reporting level.]

Data-collection site

(fig. 6)

Calcium

(mg/L)

Magnesium

(mg/L)

Potassium

(mg/L)

Sodium

(mg/L)

Bicarbonate

(mg/L)

Carbonate

(mg/L)

Bromide

(mg/L)

Chloride

(mg/L)

Fluoride

(mg/L)

Drinking-water criteria -- -- -- 20 (DWA) -- -- -- 250 (SDWR) 2 (SDWR)

Reporting level 0.03 0.05 0.07 0.05 2.0 1.0 0.03 5.0 0.02

Shallow index wells—Continued

IW-27A 112–121 (7) 19.6–20.4 (7) 2.47–2.71 (7) 35.6–43.1 (7) 320–340 (7) --–0 (7) <0.03–0.6 (7) 20–32.7 (7) 0.41–0.63 (7)

117; 119 20.1; 20.3 2.63; 2.66 39.6; 39.1 329; 330 --; -- --; -- 24.5; 24 0.54; 0.56

IW-28A 117–133 (7) 17.6–20.9 (7) 3.13–3.55 (7) 47.6–62.4 (7) 250–290 (7) --–0 (7) 0–123 (7) 24–33 (7) 0.16–0.32 (7)

126; 128 19.4; 19.2 3.31; 3.28 51.4; 49.9 266; 260 --; -- 17.6; 0.1 28.1; 28 0.25; 0.26

IW-29A 119–170 (10) 23.3–30.5 (10) 2.86–4.78 (10) 140–211 (10) 380–410 (8) --–0 (8) 0.1–0.1 (8) 17.7–59 (10) 0.11–0.42 (10)

145; 140 26.8; 26.4 3.98; 3.97 163; 150 393; 390 --; -- 0.1; 0.1 26.8; 21.9 0.31; 0.36

IW-30A 75.6–101 (9) 15.9–21 (9) 5.64–7.84 (9) 126–150 (9) 210–240 (7) --–0 (7) <0.03–0.1 (7) 147–205 (9) 0.25–0.47 (9)

87.1; 86.5 18.5; 18.5 6.74; 6.8 134; 133 233; 240 --; -- 0.100*; 0.1 165; 157 0.35; 0.37

IW-31A 93.9–127 (7) 13.2–20.7 (7) 4.19–4.96 (7) 67.3–86.8 (7) 230–270 (7) --–0 (7) 0–0.1 (7) 102–188 (7) 0.28–0.57 (7)

109; 110 16.8; 16.9 4.7; 4.86 77; 78.6 241; 230 --; -- 0.086; 0.1 136; 134 0.46; 0.52

IW-32A 70.7–97.5 (7) 13–17.6 (7) 2.5–3.41 (7) 29.6–53.2 (7) 210–270 (7) --–0 (7) <0.03–0.1 (7) 19–61 (7) 0.58–0.72 (7)

84.4; 86.8 15.4; 16.2 2.78; 2.67 38.6; 37.1 249; 260 --; -- --; -- 38.7; 36 0.65; 0.65

IW-33A 72.9–91.8 (7) 9.26–11.7 (7) 2.05–2.22 (7) 20.6–26.2 (7) 200–220 (7) --–0 (7) 0.1–0.1 (7) <5–13 (7) 0.23–0.44 (7)

82.8; 82.5 10.5; 10.4 2.15; 2.14 23.9; 24.2 213; 220 --; -- 0.1; 0.1 7.519*; 6 0.33; 0.35

IW-34A 62.4–70.5 (7) 10.7–11.9 (7) 3.19–3.57 (7) 35.4–38.2 (7) 170–180 (7) --–0 (7) 0.1–0.1 (7) 17–34 (7) 0.3–0.4 (7)

66.9; 68 11.3; 11.2 3.36; 3.31 36.5; 36.3 179; 180 --; -- 0.1; 0.1 23.3; 22 0.36; 0.36

IW-35A 85.6–93.3 (10) 21.3–25.1 (10) 4.74–6.96 (10) 313–330 (10) 300–330 (8) --–0 (8) 0.2–0.4 (8) 345–773 (10) 0.02–0.82 (10)

89.8; 89.5 23.5; 23.5 6.19; 6.33 321; 322 314; 310 --; -- 0.237; 0.2 428; 389 0.39; 0.39

IW-36A 96.8–130 (10) 19.8–26.7 (10) 0.84–4.97 (10) 249–271 (10) 190–230 (8) --–0 (8) <0.03–0.2 (8) 314–702 (10) 0.02–0.47 (10)

108; 106 21.9; 21.6 4.26; 4.76 260; 260 216; 220 --; -- 0.200*; 0.2 386; 364 0.27; 0.36

IW-37A 122–129 (7) 15.3–16.4 (7) 3.95–4.71 (7) 55.3–65.1 (7) 270–300 (7) --–0 (7) 0.1–0.1 (7) 98–122 (7) 0.2–0.42 (7)

125; 126 15.8; 15.8 4.31; 4.43 60.7; 61.5 283; 280 --; -- 0.1; 0.1 107; 106 0.3; 0.31

IW-38A 108–119 (7) 29.9–33.2 (7) 3.04–3.46 (7) 85.2–104 (7) 420–440 (7) --–0 (7) <0.03–0.1 (7) 13.5–20 (7) 0.46–0.85 (7)

113; 111 31; 30.7 3.24; 3.25 90.7; 88.6 430; 430 --; -- 0.100*; 0.1 16.8; 17 0.68; 0.7

Deep index wells

IW-01C 37.6–39.1 (7) 3.4–4.11 (7) 1.52–2.22 (7) 17.6–21.3 (7) 170–180 (7) --–0 (7) <0.03–<0.03 (6) <5–8 (7) 0.13–0.39 (6)

38.4; 38.2 3.88; 3.9 1.84; 1.87 18.8; 18.7 176; 180 --; -- --; -- --; <5 0.27; 0.26

IW-02C 38.1–44.9 (7) 4.02–4.33 (7) 1.93–2.17 (7) 17.4–19.8 (7) 170–190 (7) --–0 (7) <0.03–<0.03 (6) <5–9 (7) 0.11–0.35 (6)

40.6; 40.2 4.14; 4.1 2.05; 2.04 18.6; 18.1 176; 170 --; -- --; -- 6.217*; 6 0.2; 0.19

IW-03C 39.7–46.9 (8) 3.94–4.32 (8) 1.5–1.91 (8) 21.9–34.4 (8) 200–210 (7) --–0 (7) <0.03–0.1 (6) 5–14 (8) 0.16–0.38 (7)

44.7; 45.4 4.19; 4.23 1.74; 1.78 25; 23.4 203; 200 --; -- --; -- 7.3; 5.7 0.25; 0.25

IW-04C 79.1–91.3 (7) 9.45–11.1 (7) 3.48–5.07 (7) 51.1–59.6 (7) 200–210 (7) --–0 (7) 0.4–0.5 (6) 95–134 (7) 0.03–0.39 (6)

81.9; 80.4 9.87; 9.68 3.9; 3.73 52.9; 51.6 204; 200 --; -- 0.433; 0.4 119; 122 0.22; 0.26

IW-05C 52.7–96 (7) 8.2–15.5 (7) 3.09–4.7 (7) 37.2–49.9 (7) 150–170 (7) --–0 (7) 0.3–0.7 (7) 64–176 (7) 0.13–0.34 (7)

78.5; 80.3 12.6; 12.8 3.94; 4.03 44.2; 44.9 159; 160 --; -- 0.529; 0.6 138; 146 0.22; 0.21

IW-06C 46.2–49.1 (7) 3.84–4.49 (7) 2.09–2.45 (7) 21.7–28.9 (7) 21–210 (7) --–0 (7) <0.03–0.2 (7) 6–14.8 (7) 0.17–0.31 (7)

47.8; 48 4.18; 4.2 2.31; 2.31 24.2; 23.4 179; 200 --; -- --; <0.03 8.69; 8 0.25; 0.27

IW-07C 43.3–47.1 (7) 7.56–8.63 (7) 2.08–2.43 (7) 31.3–35.3 (7) 180–210 (7) --–0 (7) --–<0.03 (7) 8.9–12 (7) 0.14–0.38 (7)

44.8; 45 8.08; 8.04 2.26; 2.29 32.9; 32.6 189; 190 --; -- --; -- 10.1; 10 0.29; 0.31

IW-08C 373–392 (11) 71–81.7 (11) 7.09–10.9 (11) 333–409 (11) 230–240 (8) --–0 (8) <0.03–5.3 (7) 865–1,460 (10) 0.05–0.34 (10)

385; 388 76.9; 77.2 9.62; 10.2 367; 368 238; 240 --; -- 3.48*; 3.1 1,270; 1,290 0.2; 0.26

IW-09C 57.9–68.1 (7) 8.71–10.2 (7) 2.45–2.74 (7) 37.9–41.9 (7) 230–240 (7) --–0 (7) 0.1–0.2 (7) 22–51 (7) 0.27–0.44 (7)

62.9; 62 9.49; 9.34 2.6; 2.61 39.4; 39.3 237; 240 --; -- 0.114; 0.1 37.1; 31 0.35; 0.37

IW-10C 37.5–41.2 (7) 5.63–6.14 (7) 2.19–2.63 (7) 27.9–31.5 (7) 170–180 (7) --–0 (7) 0.1–0.1 (7) 14–21 (7) 0.29–0.47 (7)

39; 39 5.82; 5.8 2.38; 2.35 29.9; 29.5 171; 170 --; -- 0.1; 0.1 16.7; 17 0.36; 0.37

IW-11C 27.3–37.5 (7) 3.78–5 (7) 1.73–2.25 (7) 43–64.8 (7) 210–230 (7) --–0 (7) <0.03–<0.03 (7) 7–10 (7) 0.21–0.4 (7)

34.8; 36.3 4.66; 4.82 2; 2.03 48.8; 45.9 220; 220 --; -- --; <0.03 8; 7 0.33; 0.35

IW-12C 140–160 (8) 20–22.8 (8) 2.44–2.81 (8) 122–136 (8) 430–480 (8) --–0 (8) 0.2–0.3 (8) 68–83 (8) 0.24–0.35 (8)

149; 150 21.3; 21.2 2.67; 2.69 131; 131 455; 460 --; -- 0.25; 0.25 76.7; 77.5 0.28; 0.26

IW-13C 99.6–105 (7) 20–21.5 (7) 3.76–4.08 (7) 115–120 (7) 300–330 (7) --–0 (7) 0.1–0.1 (7) 138–165 (7) 0.06–0.57 (7)

102; 101 21; 21 3.96; 4.03 117; 117 309; 310 --; -- 0.1; 0.1 155; 158 0.44; 0.5

IW-14C 142–158 (8) 27.8–32.4 (8) 4.12–4.69 (8) 133–155 (8) 320–350 (8) --–0 (8) 0.1–0.2 (8) 116–135 (8) 0.06–0.56 (8)

149; 148 29.7; 29.2 4.41; 4.4 142; 140 331; 330 --; -- 0.125; 0.1 123; 121 0.4; 0.43

IW-15C 111–117 (7) 15.8–16.5 (7) 3.45–3.68 (7) 71.7–80.1 (7) 240–260 (7) <1–<1 (7) 0.1–0.1 (7) 71–83 (7) 0.14–0.34 (7)

113; 113 16.1; 16.2 3.59; 3.6 74.4; 73.2 250; 250 --; <1 0.1; 0.1 78.4; 79 0.27; 0.31
96 Water Quality in the Equus Beds Aquifer and the Little Arkansas River, South-Central Kansas Table A–4. Summary of major-ion and nutrient concentrations in water samples collected as part of the Equus Beds Groundwater Recharge Project, 1995–2005.—Continued [mg/L, milligrams per liter; --, not determined; DWA, Drinking-Water Advisory; SDWR, Secondary Drinking-Water Regulation; <, less than; MCL, Maximum Contaminant Level; NA, not analyzed. The first set of numbers under each heading, for example 99–3,350, indicates the range in concentration. The number in parentheses () indicates the number of samples collected. The numbers below indicate the average followed by the median. Asterisk * is value estimated by using a log-probability regression to predict the values of data below the reporting level.] Data-collection site (fig. 6) Sulfate (mg/L) Ammonia as nitrogen (mg/L) Nitrate as nitrogen, dissolved (mg/L) Nitrate as nitrogen, total (mg/L) Nitrite plus nitrate as nitrogen, dissolved (mg/L) Nitrite plus nitrate as nitrogen, total (mg/L) Nitrite as nitrogen, dissolved (mg/L) Nitrite as nitrogen, total (mg/L) Phosphorus, total (mg/L) Drinking-water criteria 250 (SDWR) -- 10 (MCL) 10 (MCL) 10 (MCL) 10 (MCL) 1 (MCL) 1 (MCL) -- Reporting level 5.0 0.03 0.01 0.01 0.02 0.02 0.02 0.02 0.01 Shallow index wells—Continued IW-27A 115–154 (7) <0.03–0.11 (7) 1.59–2.49 (7) NA 1.59–2.49 (7) NA <0.02–<0.02 (7) NA NA 135; 132 --; <0.03 1.91; 1.71 NA 1.91; 1.71 NA --; <0.02 NA NA IW-28A 218–307 (7) <0.03–0.07 (7) 0.17–2.42 (7) NA 0.17–2.42 (7) NA <0.02–<0.02 (7) NA NA 247; 234 --; 0.03 0.757; 0.46 NA 0.76; 0.46 NA --; <0.02 NA NA IW-29A 312–629 (10) 0.13–0.24 (10) <0.01–<0.01 (8) NA <0.02–0.06 (10) NA <0.01–0.06 (10) NA 0.18–0.22 (2) 445; 425 0.172; 0.17 --; <0.01 NA --; <0.02 NA --; <0.02 NA --; -- IW-30A 96–132 (9) <0.03–0.05 (9) 0.04–14.3 (7) NA 0.04–16.7 (9) NA <0.008–<0.02 (9) NA <0.06–0.03 (2) 114; 114 --; <0.04 9.84; 11.4 NA 11.1; 12.1 NA --; <0.02 NA --; -- IW-31A 61–86 (7) <0.03–0.04 (7) <0.01–17.2 (7) NA <0.02–17.2 (7) NA <0.02–<0.02 (7) NA NA 68.8; 65 --; 0.03 12.1*; 13 NA 12.095*; 13 NA --; <0.02 NA NA IW-32A 67–97 (7) <0.03–0.04 (7) 0.73–4.8 (7) NA 0.73–4.8 (7) NA <0.02–<0.02 (7) NA NA 83.6; 85 --; <0.03 2.32; 1.39 NA 2.32; 1.39 NA --; <0.02 NA NA IW-33A 35–52 (7) <0.03–0.04 (7) <0.01–20.8 (7) NA <0.02–20.8 (7) NA <0.02–<0.02 (7) NA NA 43.6; 44 --; <0.03 18.5*; 18.7 NA 18.469*; 18.7 NA --; <0.02 NA NA IW-34A 91–131 (7) <0.03–0.12 (7) <0.01–0.07 (7) NA <0.02–0.07 (7) NA <0.02–<0.02 (7) NA NA 109; 113 0.045*; 0.03 --; 0.01 NA --; 0.01 NA --; <0.02 NA NA IW-35A 155–214 (10) <0.03–0.06 (10) 0.44–1.61 (10) NA 0.44–1.63 (10) NA <0.02–0.03 (10) NA 0.03–0.03 (2) 177; 178 --; <0.03 1.09; 1.04 NA 1.1; 1.04 NA --; <0.02 NA --; -- IW-36A 152–224 (10) <0.03–0.09 (10) 12.2–20.7 (8) NA 12.2–20.7 (10) NA <0.008–<0.02 (10) NA <0.04–0.03 (2) 180; 173 --; <0.03 15.1; 13.1 NA 14.7; 13.1 NA --; <0.02 NA --; -- IW-37A 46–70 (7) <0.03–0.04 (7) 11.1–16.3 (7) NA 11.1–16.3 (7) NA <0.02–<0.02 (7) NA NA 56.7; 58 --; <0.03 14.1; 14.3 NA 14.1; 14.3 NA --; <0.02 NA NA IW-38A 160–290 (7) 0.07–0.14 (7) <0.01–0.13 (7) NA <0.02–0.13 (7) NA <0.02–<0.02 (7) NA NA 218; 209 0.113; 0.12 --; 0.03 NA --; 0.03 NA --; <0.02 NA NA Deep index wells IW-01C <5–11.2 (7) 0.15–0.2 (7) 0.03–1.94 (6) NA <0.02–1.94 (7) NA <0.02–<0.02 (6) NA NA 6.503*; 6.2 0.174; 0.17 0.363; 0.05 NA 0.312*; 0.05 NA --; <0.02 NA NA IW-02C 8–11.4 (7) 0.03–0.07 (7) 0.01–0.08 (6) NA <0.02–0.08 (7) NA <0.02–0.03 (6) NA NA 9.83; 10 0.05; 0.05 0.04; 0.035 NA 0.033*; 0.03 NA --; <0.02 NA NA IW-03C 7.31–40 (8) 0.07–0.23 (8) <0.01–<0.01 (6) NA <0.02–<0.05 (8) NA <0.008–<0.02 (7) NA --–0.2 (1) 13.5; 10 0.168; 0.175 --; <0.01 NA --; <0.02 NA --; <0.02 NA --; -- IW-04C 16–22 (7) 0.12–0.33 (7) <0.01–1.83 (6) NA <0.02–1.83 (7) NA <0.02–<0.02 (6) NA NA 18.4; 18 0.201; 0.16 --; <0.01 NA --; <0.02 NA --; <0.02 NA NA IW-05C 14–24 (7) 0.06–0.13 (7) <0.01–0.37 (7) NA <0.02–0.37 (7) NA <0.02–0.02 (7) NA NA 19; 17 0.104; 0.11 0.143*; 0.11 NA 0.150*; 0.11 NA --; <0.02 NA NA IW-06C 8–13 (7) 0.05–0.13 (7) 0.14–1.2 (7) NA 0.14–1.2 (7) NA <0.02–0.03 (7) NA NA 10.6; 10 0.074; 0.07 0.467; 0.26 NA 0.47; 0.29 NA --; <0.02 NA NA IW-07C 16.2–47 (7) 0.1–0.15 (7) <0.01–0.05 (7) NA <0.02–0.05 (7) NA <0.02–<0.02 (7) NA NA

38.5; 41 0.117; 0.11 --; <0.01 NA --; <0.02 NA --; <0.02 NA NA

IW-08C 40–74 (11) 0.04–0.18 (11) <0.01–0.96 (8) NA <0.02–0.98 (11) NA <0.02–0.023 (10) NA 0.11–0.15 (3)

47; 44 0.128; 0.14 0.522*; 0.31 NA 0.402*; 0.13 NA --; <0.02 NA --; --

IW-09C 22–31.1 (7) 0.17–0.26 (7) <0.01–0.41 (7) NA <0.02–0.41 (7) NA <0.02–<0.02 (7) NA NA

26.3; 25 0.21; 0.2 0.181*; 0.13 NA 0.181*; 0.13 NA --; <0.02 NA NA

IW-10C 20–30 (7) 0.09–0.14 (7) <0.01–0.46 (7) NA <0.02–0.46 (7) NA <0.02–<0.02 (7) NA NA

25.7; 25 0.116; 0.12 0.108*; 0.06 NA 0.108*; 0.06 NA --; <0.02 NA NA

IW-11C 15–22 (7) 0.16–0.22 (7) <0.01–0.02 (7) NA <0.02–0.02 (7) NA <0.02–<0.02 (7) NA NA

17.4; 17 0.193; 0.19 --; <0.01 NA --; <0.02 NA --; <0.02 NA NA

IW-12C 191–266 (8) 0.33–0.44 (8) <0.01–0.57 (8) NA <0.02–0.57 (8) NA <0.02–0.12 (8) NA NA

236; 238 0.375; 0.375 --; <0.01 NA 0.104*; 0.02 NA --; <0.02 NA NA

IW-13C 103–132 (7) 0.08–0.2 (7) <0.01–0.02 (7) NA <0.02–0.02 (7) NA <0.02–<0.02 (7) NA NA

116; 111 0.134; 0.12 --; <0.01 NA --; <0.02 NA --; <0.02 NA NA

IW-14C 295–402 (8) 0.12–0.24 (8) <0.01–0.09 (8) NA <0.02–0.09 (8) NA <0.02–<0.02 (8) NA NA

329; 326 0.19; 0.195 --; <0.01 NA --; <0.02 NA --; <0.02 NA NA

IW-15C 173–198 (7) 0.19–0.26 (7) <0.01–<0.01 (7) NA <0.02–<0.02 (7) NA <0.02–<0.02 (7) NA NA

186; 187 0.226; 0.23 --; <0.01 NA --; <0.02 NA --; <0.02 NA NA
Appendix 97

Table A–4. Summary of major-ion and nutrient concentrations in water samples collected as part of the Equus Beds Groundwater Recharge Project, 1995–2005.—Continued[mg/L, milligrams per liter; --, not determined; DWA, Drinking-Water Advisory; SDWR, Secondary Drinking-Water Regulation; <, less than; MCL, Maximum Contaminant Level; NA, not analyzed. The first set of numbers under each heading, for example 99–3,350, indicates the range in concentration. The number in parentheses () indicates the number of samples collected. The numbers below indicate the average followed by the median. Asterisk * is value estimated by using a log-probability regression to predict 

the values of data below the reporting level.]

Data-collection site

(fig. 6)

Orthophosphate 

(mg/L)

Orthophosphate as phosphorous 

(mg/L)

Organic carbon, total 

(mg/L)

Drinking-water criteria -- -- --

Reporting level 0.01 0.01 0.2

Shallow index wells—Continued

IW-27A 0.061–0.153 (4) <0.01–0.05 (7) 0.4–1.2 (3)

--; -- --; 0.02 --; --

IW-28A 0.031–0.159 (6) <0.01–0.052 (7) 0.4–1 (4)

0.118; 0.138 0.034*; 0.04 --; --

IW-29A 0.261–0.506 (3) <0.01–0.17 (10) 0.8–1.7 (5)

--; -- --; <0.01 --; --

IW-30A 0.089–0.123 (7) <0.01–0.04 (9) 0.7–1.7 (5)

0.096; 0.092 0.030*; 0.03 --; --

IW-31A 0.061–0.092 (4) <0.01–0.03 (7) 0.6–1.2 (3)

--; -- --; 0.02 --; --

IW-32A 0.123–0.123 (5) <0.01–0.04 (7) 0.6–1.1 (4)

--; -- 0.040*; 0.04 --; --

IW-33A 0.123–0.215 (6) <0.01–0.07 (7) 0.4–1.1 (3)

0.149; 0.123 0.045*; 0.04 --; --

IW-34A 0.031–0.092 (2) <0.01–0.03 (7) 0.6–1.2 (4)

--; -- --; <0.01 --; --

IW-35A 0.061–0.123 (3) <0.01–0.04 (10) 1–1.7 (6)

--; -- --; <0.01 1.35; 1.35

IW-36A 0.031–0.123 (5) <0.01–0.04 (10) 0.6–1.4 (5)

--; -- 0.016*; <0.01 --; --

IW-37A 0.031–0.123 (5) <0.01–0.04 (7) 0.7–1.1 (3)

--; -- 0.017*; 0.02 --; --

IW-38A 0.061–0.184 (6) <0.01–0.06 (7) 0.6–1.2 (3)

0.102; 0.092 0.030*; 0.03 --; --

Deep index wells

IW-01C 0.276–0.767 (6) 0.09–0.25 (6) 0.4–0.5 (3)

0.583; 0.613 0.19; 0.2 --; --

IW-02C 0.215–0.46 (6) 0.07–0.15 (6) 0.3–0.9 (3)

0.348; 0.353 0.113; 0.115 --; --

IW-03C 0.552–1.07 (6) <0.210–0.35 (7) 0.4–1 (4)

0.713; 0.644 0.224*; 0.21 --; --

IW-04C 0.123–0.736 (6) 0.04–0.24 (6) 0.4–1.1 (3)

0.302; 0.245 0.098; 0.08 --; --

IW-05C 0.092–0.356 (6) <0.01–0.116 (7) 0.3–0.9 (3)

0.223; 0.23 0.066*; 0.07 --; --

IW-06C 0.061–0.276 (5) <0.01–0.09 (7) 0.4–0.9 (3)

--; -- 0.048*; 0.04 --; --

IW-07C 0.184–0.491 (7) 0.06–0.16 (7) 0.4–1 (3)

0.386; 0.399 0.126; 0.13 --; --

IW-08C 0.067–0.368 (5) <0.01–0.12 (10) 0.3–1 (6)

--; -- 0.028*; <0.01 0.683; 0.7

IW-09C 0.429–0.552 (6) <0.01–0.18 (7) 0.5–0.7 (3)

0.48; 0.46 0.152*; 0.15 --; --

IW-10C 0.153–0.491 (6) <0.01–0.16 (7) 0.4–0.9 (3)

0.337; 0.353 0.099*; 0.1 --; --

IW-11C 0.307–0.767 (7) 0.1–0.25 (7) 0.7–0.8 (4)

0.635; 0.705 0.207; 0.23 --; --

IW-12C 0.061–0.429 (6) <0.01–0.14 (8) 1.4–2.2 (3)

0.184; 0.153 0.047*; 0.03 --; --

IW-13C 0.031–0.184 (3) <0.01–0.06 (7) 0.5–1.2 (4)

--; -- --; <0.01 --; --

IW-14C 0.092–0.092 (3) <0.01–0.03 (8) 0.9–1.4 (4)

--; -- --; <0.01 --; --

IW-15C 0.153–0.215 (5) <0.01–0.07 (7) 0.7–1.3 (3)

--; -- 0.053*; 0.05 --; --
98 Water Quality in the Equus Beds Aquifer and the Little Arkansas River, South-Central Kansas Table A–4. Summary of major-ion and nutrient concentrations in water samples collected as part of the Equus Beds Groundwater Recharge Project, 1995–2005.—Continued [mg/L, milligrams per liter; --, not determined; DWA, Drinking-Water Advisory; SDWR, Secondary Drinking-Water Regulation; <, less than; MCL, Maximum Contaminant Level; NA, not analyzed. The first set of numbers under each heading, for example 99–3,350, indicates the range in concentration. The number in parentheses () indicates the number of samples collected. The numbers below indicate the average followed by the median. Asterisk * is value estimated by using a log-probability regression to predict the values of data below the reporting level.] Data-collection site (fig. 6) Calcium (mg/L) Magnesium (mg/L) Potassium (mg/L) Sodium (mg/L) Bicarbonate (mg/L) Carbonate (mg/L) Bromide (mg/L) Chloride (mg/L) Fluoride (mg/L) Drinking-water criteria -- -- -- 20 (DWA) -- -- -- 250 (SDWR) 2 (SDWR) Reporting level 0.03 0.05 0.07 0.05 2.0 1.0 0.03 5.0 0.02 Deep index wells—Continued IW-16C 103–123 (7) 15.5–18.5 (7) 3.24–3.63 (7) 42.9–45.2 (7) 180–210 (7) <1–<1 (7) 0–0.1 (7) 16–22 (7) 0.16–0.32 (7) 112; 108 16.9; 16.4 3.42; 3.45 44; 43.8 191; 190 --; <1 0.086; 0.1 18.7; 18 0.22; 0.22 IW-17C 50–59.7 (7) 7.48–8.93 (7) 2.02–2.1 (7) 52.6–57.1 (7) 270–410 (7) --–0 (7) 0–0.1 (7) 11–14 (7) 0.05–0.4 (7) 53.8; 52.4 8.06; 7.91 2.06; 2.07 55.8; 56.1 294; 280 --; -- 0.043; 0 12.4; 12 0.31; 0.35 IW-18C 88.5–98.7 (7) 17.3–18.7 (7) 3.73–4.09 (7) 94.8–104 (7) 310–320 (7) --–0 (7) 0.1–0.1 (7) 110–124 (7) 0.55–0.68 (7) 93.6; 92.9 18; 17.8 3.89; 3.85 99.4; 99.1 313; 310 --; -- 0.1; 0.1 116; 115 0.6; 0.59 IW-19C 75.6–76.8 (7) 15.8–16.6 (7) 3.6–3.9 (7) 104–115 (7) 330–330 (7) <1–<1 (7) 0.1–0.1 (7) 94–113 (7) 0.3–0.53 (7) 76.1; 76 16.3; 16.4 3.76; 3.8 110; 111 330; 330 --; <1 0.1; 0.1 105; 108 0.43; 0.45 IW-20C 139–164 (10) 25.1–31.2 (10) 3.49–4.69 (10) 96.3–109 (10) 280–300 (8) --–0 (8) <0.03–0.3 (8) 45–105 (10) 0.08–0.54 (10) 151; 153 27.9; 27.4 4.42; 4.59 101; 100 291; 290 --; -- 0.120*; 0.1 58.9; 55.3 0.43; 0.46 IW-21C 200–209 (8) 36–38.9 (8) 4.7–4.96 (8) 131–145 (8) 320–360 (8) <1–<1 (8) 0.1–0.2 (8) 91.4–124 (8) 0.06–0.48 (8) 205; 206 37; 36.7 4.85; 4.86 137; 137 338; 340 --; <1 0.163; 0.2 110; 113 0.3; 0.32 IW-22C 73.7–79.9 (7) 11.8–12.5 (7) 2.63–3.01 (7) 60.6–65.5 (7) 300–310 (7) --–0 (7) 0–0.1 (7) 18–23 (7) 0.43–0.59 (7) 75.2; 74.4 12.2; 12.3 2.81; 2.8 63; 62.8 307; 310 --; -- 0.057; 0.1 20.9; 21 0.51; 0.51 IW-23C 60.5–66 (7) 10.4–11.1 (7) 2.66–2.83 (7) 68.2–73.1 (7) 290–320 (7) --–0 (7) 0–0.1 (7) 26–33 (7) 0.38–0.51 (7) 63.7; 63.8 10.9; 11.1 2.74; 2.77 70.4; 69.8 309; 310 --; -- 0.071; 0.1 30.5; 31 0.46; 0.47 IW-24C 52–57.9 (8) 11.8–13.3 (8) 2.96–3.93 (8) 170–191 (8) 290–300 (7) --–0 (7) 0.1–0.1 (7) 170–215 (8) 0.55–0.73 (8) 54.2; 53.6 12.3; 12.2 3.55; 3.61 179; 180 297; 300 --; -- 0.1; 0.1 189; 191 0.66; 0.67 IW-25C 55.2–93.8 (10) 12.4–16.7 (10) 2.76–4.18 (10) 104–195 (10) 300–350 (8) --–0 (8) 0.1–0.1 (8) 23–126 (10) <0.02–0.71 (10) 75.7; 71.5 15.2; 15.1 3.69; 3.83 117; 108 320; 320 --; -- 0.1; 0.1 94.9; 99 0.616*; 0.6 IW-26C 76–81.8 (6) 16.4–17.5 (6) 3.74–5.61 (6) 92.3–99.6 (6) 320–340 (6) --–0 (6) 0–0.1 (6) 81–104 (6) 0.42–0.49 (6) 78.1; 77.5 17; 17 4.24; 4.01 97.1; 97.9 333; 335 --; -- 0.083; 0.1 92.1; 91 0.45; 0.45 IW-27C 66.6–70.7 (7) 12.9–13.5 (7) 3.13–3.51 (7) 88.6–97.3 (7) 320–330 (7) --–0 (7) 0–0.1 (7) 51–65 (7) 0.34–0.45 (7) 68.2; 68 13.3; 13.4 3.37; 3.39 92.5; 92.7 329; 330 --; -- 0.086; 0.1 58.6; 60 0.4; 0.4

IW-28C 67.1–73.2 (7) 13.4–14.5 (7) 3.36–3.65 (7) 99.6–109 (7) 320–340 (7) --–0 (7) 0–0.1 (7) 65–85 (7) 0.17–0.4 (7)

70.2; 70 13.9; 13.8 3.53; 3.58 104; 104 334; 340 --; -- 0.071; 0.1 74.3; 73 0.32; 0.34

IW-29C 82.2–96.1 (7) 14.1–15.7 (7) 3.03–3.43 (7) 98.9–107 (7) 320–350 (7) --–0 (7) <0.03–0.1 (7) 36–53 (7) 0.27–0.43 (7)

89.4; 90.2 15.1; 15.2 3.25; 3.26 103; 103 334; 330 --; -- 0.100*; 0.1 43.4; 43 0.36; 0.38

IW-30C 88.4–100 (11) 30.1–33.3 (11) 2.92–4.15 (11) 185–196 (11) 260–280 (8) --–0 (8) 0.1–0.1 (8) 184–272 (11) 0.29–0.45 (11)

92.3; 91.5 32.1; 32.4 3.75; 3.96 192; 193 270; 270 --; -- 0.1; 0.1 211; 199 0.38; 0.39

IW-31C 86.4–93 (8) 18.8–20.8 (8) 3.6–4.2 (8) 95.9–108 (8) 300–320 (7) --–0 (7) 0.1–0.1 (7) 111–130 (8) 0.23–0.38 (8)

90; 90.5 20; 20.1 3.96; 4.03 102; 103 314; 320 --; -- 0.1; 0.1 119; 119 0.31; 0.34

IW-32C 77.1–82.8 (7) 12–13.1 (7) 2.93–3.38 (7) 70.6–80.4 (7) 300–320 (7) --–0 (7) 0.1–0.1 (7) 50–70 (7) 0.52–0.65 (7)

79.2; 78.7 12.3; 12.1 3.15; 3.17 73.8; 71.4 306; 300 --; -- 0.1; 0.1 61.9; 62 0.59; 0.62

IW-33C 72.8–80 (7) 13.9–15 (7) 3.2–3.71 (7) 82.6–91.2 (7) 320–330 (7) --–0 (7) 0.1–0.1 (7) 59–66 (7) 0.33–0.42 (7)

76.5; 77.4 14.6; 14.7 3.46; 3.47 86.1; 86 326; 330 --; -- 0.1; 0.1 61.4; 60 0.4; 0.41

IW-34C 70.8–79 (7) 13.2–15.5 (7) 3.37–3.82 (7) 67.6–77.5 (7) 320–330 (7) --–0 (7) 0–0.1 (7) 48–57 (7) 0.39–0.51 (7)

75.5; 76.3 14.5; 14.7 3.56; 3.57 72.4; 72 327; 330 --; -- 0.057; 0.1 52.3; 53 0.46; 0.46

IW-35C 106–115 (10) 18.2–20.7 (10) 4.57–5.94 (10) 132–150 (10) 200–230 (8) --–0 (8) 0.1–0.1 (8) 256–424 (10) 0.07–0.51 (10)

109; 109 19.7; 19.9 5.3; 5.33 138; 138 221; 225 --; -- 0.1; 0.1 286; 265 0.34; 0.37

IW-36C 96.4–174 (7) 18.5–31.4 (7) 4.3–5.81 (7) 95.5–127 (7) 260–290 (7) --–0 (7) 0.1–0.2 (7) 157–285 (7) 0.28–0.41 (7)

125; 120 23.6; 23 4.85; 4.77 106; 103 276; 280 --; -- 0.114; 0.1 215; 216 0.35; 0.35

IW-37C 69.8–75.5 (7) 12–13 (7) 3.25–3.46 (7) 74.1–78 (7) 280–300 (7) --–0 (7) 0.1–0.1 (7) 61–75.4 (7) 0.44–0.59 (7)

73.5; 74.2 12.6; 12.8 3.38; 3.39 76.6; 76.8 291; 290 --; -- 0.1; 0.1 67.6; 65 0.53; 0.54

IW-38C 93.8–105 (7) 18.2–19.9 (7) 3.34–3.81 (7) 56.2–63.6 (7) 340–380 (7) --–0 (7) <0.03–0.1 (7) 21–37.8 (7) 0.55–0.67 (7)

97.1; 95.5 18.7; 18.4 3.53; 3.58 60.6; 61.8 354; 350 --; -- 0.100*; 0.1 26; 26 0.61; 0.62
Appendix 99

Table A–4. Summary of major-ion and nutrient concentrations in water samples collected as part of the Equus Beds Groundwater Recharge Project, 1995–2005.—Continued[mg/L, milligrams per liter; --, not determined; DWA, Drinking-Water Advisory; SDWR, Secondary Drinking-Water Regulation; <, less than; MCL, Maximum Contaminant Level; NA, not analyzed. The first set of numbers under each heading, for example 99–3,350, indicates the range in concentration. The number in parentheses () indicates the number of samples collected. The numbers below indicate the average followed by the median. Asterisk * is value estimated 

by using a log-probability regression to predict the values of data below the reporting level.]

Data-collection site

(fig. 6)

Sulfate

(mg/L)

Ammonia as nitrogen

(mg/L)

Nitrate as nitrogen, 

dissolved 

(mg/L)

Nitrate as nitrogen,

total 

(mg/L)

Nitrite plus nitrate as 

nitrogen, dissolved 

(mg/L)

Nitrite plus nitrate 

as nitrogen, total 

(mg/L)

Nitrite as nitrogen, 

dissolved 

(mg/L)

Nitrite as nitrogen,

total 

(mg/L)

Phosphorus, 

total 

(mg/L)

Drinking-water criteria 250 (SDWR) -- 10 (MCL) 10 (MCL) 10 (MCL) 10 (MCL) 1 (MCL) 1 (MCL) --

Reporting level 5.0 0.03 0.01 0.01 0.02 0.02 0.02 0.02 0.01

Deep index wells—Continued

IW-16C 227–318 (7) 0.17–0.27 (7) <0.01–0.02 (7) NA <0.02–0.02 (7) NA <0.02–<0.02 (7) NA NA

267; 257 0.229; 0.24 --; <0.01 NA --; <0.02 NA --; <0.02 NA NA

IW-17C 29–56 (7) 0.12–0.24 (7) <0.01–0.01 (7) NA <0.02–0.01 (7) NA <0.02–<0.02 (7) NA NA

41.3; 43 0.164; 0.17 --; <0.01 NA --; <0.02 NA --; <0.02 NA NA

IW-18C 72–100 (7) 0.04–0.08 (7) <0.01–0.02 (7) NA <0.02–0.02 (7) NA <0.02–<0.02 (7) NA NA

84.1; 87 0.054; 0.05 --; <0.01 NA --; <0.02 NA --; <0.02 NA NA

IW-19C 67–91 (7) 0.1–0.17 (7) <0.01–0.02 (7) NA <0.02–0.02 (7) NA <0.02–<0.02 (7) NA NA

72.9; 71 0.14; 0.14 --; <0.01 NA --; <0.02 NA --; <0.02 NA NA

IW-20C 235–489 (10) 0.16–0.27 (10) <0.01–0.09 (8) NA <0.02–0.21 (10) NA <0.008–0.12 (10) NA 0.18–0.19 (2)

375; 364 0.22; 0.235 --; <0.01 NA --; <0.02 NA --; <0.02 NA --; --

IW-21C 352–890 (8) 0.09–0.22 (8) <0.01–<0.01 (8) NA <0.02–<0.02 (8) NA <0.02–<0.02 (8) NA NA

505; 449 0.171; 0.19 --; <0.01 NA --; <0.02 NA --; <0.02 NA NA

IW-22C 74–94 (7) 0.06–0.12 (7) <0.01–<0.01 (7) NA <0.02–<0.02 (7) NA <0.02–<0.02 (7) NA NA

82.7; 83 0.091; 0.08 --; <0.01 NA --; <0.02 NA --; <0.02 NA NA

IW-23C 39–72.8 (7) 0.11–0.22 (7) <0.01–<0.01 (7) NA <0.02–<0.02 (7) NA <0.02–<0.02 (7) NA NA

50.4; 45 0.153; 0.14 --; <0.01 NA --; <0.02 NA --; <0.02 NA NA

IW-24C 69–88 (8) <0.03–0.03 (8) 0.02–0.29 (7) NA 0.02–0.29 (8) NA <0.008–<0.02 (8) NA --–0.03 (1)

76.7; 75.7 --; <0.03 0.173; 0.15 NA 0.17; 0.15 NA --; <0.02 NA --; --

IW-25C 58–101 (10) <0.03–0.05 (10) <0.01–0.12 (8) NA <0.02–0.12 (10) NA <0.008–<0.02 (10) NA 0.03–0.03 (2)

76.9; 73.5 --; <0.03 0.063*; 0.05 NA 0.057*; <0.06 NA --; <0.02 NA --; --

IW-26C 52–84 (6) 0.08–0.14 (6) <0.01–0.12 (6) NA <0.02–0.12 (6) NA <0.02–<0.02 (6) NA NA

65.2; 63.5 0.097; 0.09 --; <0.01 NA --; <0.02 NA --; <0.02 NA NA

IW-27C 46–72.6 (7) 0.11–0.16 (7) <0.01–0.35 (7) NA <0.02–0.35 (7) NA <0.02–<0.02 (7) NA NA

58.8; 55 0.133; 0.14 0.115*; 0.06 NA 0.115*; 0.06 NA --; <0.02 NA NA

IW-28C 50–73 (7) 0.04–0.11 (7) <0.01–0.21 (7) NA <0.02–0.21 (7) NA <0.02–<0.02 (7) NA NA

60.3; 62 0.056; 0.05 0.063*; 0.05 NA 0.063*; 0.05 NA --; <0.02 NA NA

IW-29C 143–225 (7) 0.11–0.17 (7) <0.01–0.16 (7) NA <0.02–0.16 (7) NA <0.02–<0.02 (7) NA NA

172; 167 0.146; 0.15 --; <0.01 NA --; <0.02 NA --; <0.02 NA NA

IW-30C 216–418 (11) <0.03–0.07 (11) <0.01–0.71 (8) NA <0.02–0.71 (11) NA <0.008–<0.02 (11) NA 0.04–0.06 (3)

286; 261 0.040*; 0.04 --; <0.01 NA 0.126*; <0.06 NA --; <0.02 NA --; --

IW-31C 91–113 (8) 0.06–0.12 (8) <0.01–0.63 (7) NA <0.02–0.63 (8) NA <0.008–<0.02 (8) NA --–0.03 (1)

102; 103 0.08; 0.08 0.142*; 0.05 NA 0.126*; 0.01 NA --; <0.02 NA --; --

IW-32C 38–63 (7) <0.03–0.08 (7) <0.01–2.93 (7) NA <0.02–2.93 (7) NA <0.02–<0.02 (7) NA NA

50.7; 48 --; <0.03 2.14*; 2.18 NA 2.142*; 2.18 NA --; <0.02 NA NA

IW-33C 61–80 (7) <0.03–0.06 (7) <0.01–1.18 (7) NA <0.02–1.18 (7) NA <0.02–<0.02 (7) NA NA

70; 67 --; <0.03 0.461*; 0.35 NA 0.461*; 0.35 NA --; <0.02 NA NA

IW-34C 42–58 (7) <0.03–0.04 (7) 0.06–0.51 (7) NA 0.06–0.51 (7) NA <0.02–0.09 (7) NA NA

51.3; 51 --; <0.03 0.247; 0.26 NA 0.27; 0.26 NA --; <0.02 NA NA

IW-35C 69–85 (10) <0.03–0.04 (10) <0.01–0.46 (8) NA <0.02–0.46 (10) NA <0.008–<0.02 (10) NA 0.03–0.04 (2)

74.9; 74.9 --; <0.03 0.074*; 0.02 NA 0.065*; 0.02 NA --; <0.02 NA --; --

IW-36C 59–132 (7) <0.03–0.13 (7) 4.93–9.61 (7) NA 4.93–9.61 (7) NA <0.02–<0.02 (7) NA NA

95.9; 95 --; <0.03 6.81; 6.67 NA 6.81; 6.67 NA --; <0.02 NA NA

IW-37C 38–55 (7) <0.03–0.07 (7) 3.37–7.09 (7) NA 3.45–7.09 (7) NA <0.02–0.2 (7) NA NA

45.9; 42 --; <0.03 4.31; 3.92 NA 4.37; 3.93 NA 0.066*; 0.05 NA NA

IW-38C 83–138 (7) 0.04–0.08 (7) <0.01–0.3 (7) NA <0.02–0.3 (7) NA <0.02–<0.02 (7) NA NA

114; 119 0.057; 0.06 --; <0.01 NA --; <0.02 NA --; <0.02 NA NA
100 Water Quality in the Equus Beds Aquifer and the Little Arkansas River, South-Central Kansas Table A–4. Summary of major-ion and nutrient concentrations in water samples collected as part of the Equus Beds Groundwater Recharge Project, 1995–2005.—Continued [mg/L, milligrams per liter; --, not determined; DWA, Drinking-Water Advisory; SDWR, Secondary Drinking-Water Regulation; <, less than; MCL, Maximum Contaminant Level; NA, not analyzed. The first set of numbers under each heading, for example 99–3,350, indicates the range in concentration. The number in parentheses () indicates the number of samples collected. The numbers below indicate the average followed by the median. Asterisk * is value estimated by using a log-probability regression to predict the values of data below the reporting level.] Data-collection site (fig. 6) Orthophosphate (mg/L) Orthophosphate as phosphorous (mg/L) Organic carbon, total (mg/L) Drinking-water criteria -- -- -- Reporting level 0.01 0.01 0.2 Deep index wells—Continued IW-16C 0.184–0.276 (3) <0.01–0.09 (7) 0.8–1.5 (4) --; -- --; <0.01 --; -- IW-17C 0.061–0.368 (5) <0.01–0.12 (7) 0.7–1.2 (3) --; -- 0.042*; 0.03 --; -- IW-18C --–0.153 (1) <0.01–0.05 (7) 0.4–1 (3) --; -- --; <0.01 --; -- IW-19C 0.123–0.184 (6) <0.01–0.06 (7) 0.5–1.2 (3) 0.148; 0.153 0.046*; 0.05 --; -- IW-20C 0.061–0.46 (9) <0.01–0.15 (10) 0.8–2.4 (5) 0.241; 0.276 0.072*; 0.05 --; -- IW-21C 0.092–0.153 (3) <0.01–0.05 (8) 1–1.8 (4) --; -- --; <0.01 --; -- IW-22C 0.061–0.245 (6) <0.01–0.08 (7) 0.8–1.8 (3) 0.163; 0.154 0.048*; 0.04 --; -- IW-23C 0.184–0.399 (7) 0.06–0.13 (7) 0.6–1.3 (3) 0.25; 0.215 0.081; 0.07 --; -- IW-24C 0.061–0.153 (5) <0.01–0.05 (8) 0.2–1 (4) --; -- 0.029*; 0.03 --; -- IW-25C 0.061–0.184 (9) <0.01–0.06 (10) 0.3–2.5 (5) 0.109; 0.095 0.033*; 0.03 --; -- IW-26C 0.061–0.123 (3) <0.01–0.04 (6) 0.5–1.1 (3) --; -- --; <0.01 --; -- IW-27C 0.092–0.092 (3) <0.01–0.03 (7) 0.5–1.2 (3) --; -- --; <0.01 --; --

IW-28C 0.061–0.123 (4) <0.01–0.04 (7) 0.4–1.1 (4)

--; -- --; 0.02 --; --

IW-29C 0.061–0.276 (3) <0.01–0.09 (7) 0.7–1.4 (3)

--; -- --; <0.01 --; --

IW-30C 0.061–0.184 (8) <0.01–0.06 (11) <0.2–4.3 (6)

0.139; 0.153 0.038*; 0.05 1.26*; 0.8

IW-31C 0.061–0.092 (5) <0.01–0.03 (8) 0.4–0.9 (4)

--; -- 0.020*; 0.02 --; --

IW-32C 0.061–0.092 (4) <0.01–0.03 (7) 0.3–0.9 (4)

--; -- --; 0.02 --; --

IW-33C 0.092–0.123 (5) <0.01–0.04 (7) 0.3–0.9 (3)

--; -- 0.030*; 0.03 --; --

IW-34C 0.092–0.245 (4) <0.01–0.08 (7) 0.3–0.9 (4)

--; -- 0.035*; 0.03 --; --

IW-35C 0.031–0.184 (8) <0.01–0.06 (10) 0.2–0.9 (6)

0.101; 0.083 0.027*; 0.02 0.433; 0.35

IW-36C 0.061–0.153 (2) <0.01–0.05 (7) 0.3–0.7 (3)

--; -- --; <0.01 --; --

IW-37C 0.061–0.123 (6) <0.01–0.04 (7) 0.3–1 (3)

0.076; 0.061 0.023*; 0.02 --; --

IW-38C 0.031–0.337 (7) 0.01–0.11 (7) 0.5–1 (3)

0.171; 0.153 0.056; 0.05 --; --
Appendix 10

1

Table A–5. Summary of dissolved trace element concentrations in water samples collected as part of the Equus Beds Groundwater Recharge Project during 1995–2005.[μg/L, micrograms per liter; SDWR, Secondary Drinking-Water Regulation; MCL, Maximum Contaminant Level; --, not determined; HAL, Health Advisory Level; <, less than; NA, not analyzed. The first set of numbers under each heading, for example 99–3,350, indicates the range in concentration. The number in parentheses () indicates the number of samples collected. The numbers below indicate the average followed by the median. Asterisk * is value estimated by using a log-probability regression to predict the values of data below the reporting level.]

Data-collection site

(fig. 6)

Aluminum

(μg/L)

Antimony

(μg/L)

Arsenate as arsenic

(μg/L)

Arsenic

(μg/L)

Arsenite as arsenic

(μg/L)

Barium

(μg/L)

Beryllium

(μg/L)

Boron

(μg/L)

Cadmium

(μg/L)

Drinking-water criteria 50–200 (SDWR) 6 (MCL) -- 10 (MCL) -- 2,000 (MCL) 4 (MCL) 1,000 (HAL) 5 (MCL)

Reporting level 10.0 2 0.2 1.0 0.1 5.0 1.0 10.0 0.1

Surface-water monitoring sites (Little Arkansas River)

7143672 

(near Halstead)

<0.01–273 (52) <2–3 (52) 1.4–10.1 (8) 1.2–14.1 (82) <0.1–0.3 (8) 45.4–358 (52) <0.06–<1 (52) 20–130 (52) <0.1–0.05 (52)

14.4*; <10 --; <2 3.75; 3.05 5.54; 5.05 --; <0.6 161; 126 --; <1 60.3; 50 --; <0.1

7144100 

(near Sedgwick)

<8–841 (56) <2–0.27 (55) 1.5–12.5 (8) 1–14.1 (84) <0.1–0.3 (8) 43.8–270 (56) <0.06–<1 (56) 20–200 (56) <0.1–0.06 (56)

28.7*; <10 --; <2 4.21; 3.3 5.34; 4.75 --; <0.6 122; 95.6 --; <1 63.2; 50 --; <0.1

Diversion well site near Halstead

Diversion well <10–11 (31) <2–3 (31) --–1.8 (1) 15.7–24.4 (35) --–15.9 (1) 82.8–337 (31) <1–<1 (31) 40–60 (31) <0.1–<0.5 (31)

--; <10 --; <2 --; -- 20.1; 20 --; -- 140; 137 --; <1 52.6; 50 --; <0.1

EB-145-A1 <8–14 (19) <0.3–<2 (20) <0.2–<0.8 (5) <1–10 (33) <0.1–0.5 (5) 342–835 (19) <0.06–<1 (19) 40–120 (19) <0.01–<0.5 (19)

7.31*; <10 --; <2 --; -- --; <1 --; -- 580; 588 --; <1 72.6; 70 --; <0.1

EB-145-A2 <10–10 (10) <2–<2 (10) 0.4–1.2 (2) <1–3.7 (13) <0.1–0.7 (2) 391–496 (10) <1–<1 (10) 60–80 (10) <0.1–<0.5 (10)

--; <10 --; <2 --; -- 1.34*; 1.2 --; -- 429; 426 --; <1 70; 70 --; <0.1

EB-145-A3 <10–<10 (10) <2–4 (10) <0.8–0.4 (2) <1–2.4 (13) 0.5–1 (2) 228–310 (10) <1–<1 (10) 50–80 (10) <0.01–<0.5 (10)

--; <10 --; <2 --; -- 1.26*; <1 --; -- 268; 261 --; <1 66; 70 --; <0.1

EB-145-A4 <10–<10 (7) <2–<2 (7) 5.7–5.8 (2) 14.8–22.3 (9) 11.1–11.8 (2) 102–279 (7) <1–<1 (7) 40–50 (7) <0.1–<0.5 (7)

--; <10 --; <2 --; -- 17.2; 16.8 --; -- 202; 225 --; <1 48.6; 50 --; --

EB-145-A5 <10–<10 (8) <2–3 (8) 2.4–5 (3) 19.2–31.8 (15) 17–19 (3) 189–268 (8) <1–<1 (8) 40–50 (8) <0.1–<0.5 (8)

--; <10 --; <2 --; -- 25.6; 25.2 --; -- 225; 220 --; <1 47.5; 50 --; <0.1

EB-145-P-D5 <1–<10 (15) <2–<2 (15) 0.5–3.4 (5) 18.5–48.9 (28) 28.4–40.7 (5) 67.8–144 (15) <1–<1 (15) 40–60 (15) <0.1–<0.5 (15)

--; <10 --; <2 --; -- 29.1; 26.7 --; -- 95.7; 88.5 --; <1 50; 50 --; <0.1

Halstead recharge site

SMW-H4 <10–<10 (19) <2–<2 (19) 1.3–1.8 (3) <1–2.9 (26) <0.1–<0.6 (3) 161–331 (19) <1–<1 (19) 30–60 (19) <0.1–<0.5 (19)

--; <10 --; <2 --; -- 1.78*; 1.7 --; -- 277; 289 --; <1 48.9; 50 --; <0.1

SMW-H14 <10–<10 (20) <2–3 (20) 1.6–2.2 (3) <1–4.3 (28) <0.1–<0.6 (3) 203–488 (20) <1–<1 (20) 40–100 (20) <0.1–<0.5 (20)

--; <10 --; <2 --; -- 2.25*; 2.2 --; -- 279; 272 --; <1 57; 50 --; <0.1

DMW-H1 <10–<10 (19) <2–3 (19) 0.4–1.5 (3) 8.1–23.4 (27) 16.1–16.9 (3) 75.7–155 (19) <1–<1 (19) 40–60 (19) <0.1–<0.5 (19)

--; <10 --; <2 --; -- 17.3; 19.1 --; -- 125; 141 --; <1 50; 50 --; <0.1

DMW-H13 <10–<10 (20) <2–3 (20) 0.4–2.3 (3) 4.6–13.7 (28) 8.9–10.3 (3) 146–388 (20) <1–<1 (20) 40–70 (20) <0.1–<0.5 (20)

--; <10 --; <2 --; -- 9.89; 10.6 --; -- 270; 328 --; <1 47.5; 50 --; <0.1

Sedgwick recharge site

Treated stream water <10–23 (13) <2–9 (13) NA 2.1–5.9 (13) NA 57.5–211 (13) <1–<1 (13) 40–70 (13) <0.1–<0.1 (13)

--; <10 --; <2 NA 3.81; 3.6 NA 120; 105 --; <1 55.4; 50 --; <0.1

SMW-S11 <10–<10 (15) <2–<2 (16) <0.2–2.8 (3) <1–2.7 (23) <0.1–<0.6 (3) 89–152 (15) <1–<1 (15) 20–80 (15) <0.1–<0.5 (15)

--; <10 --; <2 --; -- --; <1 --; -- 119; 117 --; <1 51.3; 50 --; <0.1

SMW-S13 <10–<10 (15) <2–<2 (15) <0.8–0.4 (3) <1–1.3 (22) <0.1–<0.6 (3) 57.2–144 (15) <1–<1 (15) 20–60 (15) <0.1–<0.5 (15)

--; <10 --; <2 --; -- --; <1 --; -- 95.6; 89.3 --; <1 48; 50 --; <0.1

DMW-S10 <10–<10 (14) <2–<2 (15) 2.2–2.7 (3) 1.8–3.6 (22) <0.1–<0.6 (3) 51–66.3 (14) <1–<1 (14) 30–60 (14) <0.1–<0.5 (14)

--; <10 --; <2 --; -- 2.91; 3.05 --; -- 57; 55.9 --; <1 47.1; 50 --; <0.1

DMW-S14 <10–11 (13) <2–<2 (13) 3.6–3.7 (3) 2.7–5 (20) <0.1–<0.6 (3) 23–53.3 (13) <1–<1 (13) 30–50 (13) <0.1–<0.5 (13)

--; <10 --; <2 --; -- 4.12; 4.05 --; -- 32.4; 29.4 --; <1 43.8; 50 --; <0.1
102 Water Quality in the Equus Beds Aquifer and the Little Arkansas River, South-Central Kansas Table A–5. Summary of dissolved trace element concentrations in water samples collected as part of the Equus Beds Groundwater Recharge Project during 1995–2005.— Continued. [μg/L, micrograms per liter; SDWR, Secondary Drinking-Water Regulation; MCL, Maximum Contaminant Level; --, not determined; HAL, Health Advisory Level; <, less than; NA, not analyzed. The first set of numbers under each heading, for example 99–3,350, indicates the range in concentration. The number in parentheses () indicates the number of samples collected. The numbers below indicate the average followed by the median. Asterisk * is value esti- mated by using a log-probability regression to predict the values of data below the reporting level.] Data-collection site (fig. 6) Chromium (μg/L) Copper (μg/L) Cyanide (μg/L) Iron (μg/L) Lead (μg/L) Manganese (μg/L) Mercury (μg/L) Molybdenum (μg/L) Nickel (μg/L) Drinking-water criteria 100 (MCL) 1,300 (MCL) 200 (MCL) 300 (SDWR) 15 (MCL) 50 (SDWR) 2 (MCL) -- 100 (HAL) Reporting level 10.0 5.0 0.001 5.0 1.0 1.0 0.02 -- 1.0 Surface-water monitoring sites (Little Arkansas River) 7143672 <0.8–<10 (52) <5–1.7 (52) <0.001–6 (50) <5–860 (186) <1–0.39 (52) <1–1,140 (185) <0.02–0.14 (51) --–7.2 (1) <1–7.5 (52) (near Halstead) --; <10 --; <5 --; <0.01 28.8*; 10 --; <1 193*; 120 0.038*; <0.1 --; -- --; -- 7144100 <0.8–<10 (56) <3–1.9 (56) <0.001–5 (54) <5–620 (161) <1–0.09 (56) <1–740 (161) <0.02–0.45 (54) --–5.6 (1) <1–6.69 (56) (near Sedgwick) --; <10 --; <5 --; <0.01 37.9*; 20 --; <1 94.2*; 40 0.051*; <0.1 --; -- --; <1 Diversion well site near Halstead Diversion well <8–<10 (31) <5–<5 (31) <0.001–<5 (31) 30–1,150 (150) <1–<1 (31) 450–830 (150) <0.02–0.17 (31) NA <1–<1 (31) --; <10 --; <5 --; <0.01 414; 430 --; <1 685; 725 --; <0.1 NA --; <1 EB-145-A1 <8–0.7 (19) <5–0.4 (19) <0.001–1 (18) 1,630–6,250 (66) <0.08–<1 (19) 1,180–3,850 (66) <0.02–0.04 (18) --–0.5 (1) <1–2.5 (19) --; <10 --; <5 --; <0.01 3,170; 3,010 --; <1 2,380; 2,350 --; <0.1 --; -- --; <1 EB-145-A2 <8–<10 (10) <5–<5 (10) <0.001–1 (10) 1,640–2,670 (28) <1–<1 (10) 900–1,510 (28) <0.02–0.03 (10) NA <1–<1 (10) --; <8 --; <5 --; <0.01 2,110; 2,050 --; <1 1,180; 1,160 --; <0.1 NA --; <1 EB-145-A3 <8–<10 (10) <5–<5 (10) <0.001–1 (10) 260–1,240 (33) <1–<1 (10) 800–1,280 (33) <0.02–<0.1 (10) NA <1–<3 (10) --; <8 --; <5 --; <0.01 791; 770 --; <1 1,040; 1,030 --; <0.1 NA --; <1 EB-145-A4 <8–<10 (7) <5–<5 (7) <0.001–<0.01 (7) 80–590 (21) <1–<1 (7) 380–1,010 (21) <0.02–<0.1 (7) NA <0.1–<1 (7) --; -- --; <5 --; <0.01 403; 370 --; <1 660; 680 --; <0.1 NA --; -- EB-145-A5 <8–<10 (8) <5–<5 (8) <0.001–0.01 (8) 70–540 (32) <1–<1 (8) 640–980 (32) <0.02–<0.1 (8) NA <1–<1 (8) --; <10 --; <5 --; <0.01 347; 380 --; <1 814; 825 --; <0.1 NA --; -- EB-145-P-D5 <1–<10 (15) <5–<5 (15) <0.001–<0.01 (15) 10–740 (58) <1–<1 (15) 380–1,000 (58) <0.02–0.1 (15) NA <1–<3 (15) --; <10 --; <5 --; <0.01 273; 240 --; <1 569; 575 --; <0.1 NA --; <1 Halstead recharge site SMW-H4 <10–<10 (19) <5–<5 (19) <0.001–0.01 (19) <5–50 (47) <1–<1 (19) <1–20 (47) <0.02–0.08 (19) NA <1–<1 (19) --; <10 --; <5 --; <0.01 --; <5 --; <1 --; <5 --; <0.1 NA --; -- SMW-H14 <10–<10 (20) <5–<5 (20) <0.001–0.01 (20) <5–20 (46) <1–<1 (20) <5–70 (46) <0.02–0.27 (20) NA --–<1 (20) --; <10 --; <5 --; <0.01 --; <5 --; <1 --; <5 --; <0.1 NA --; -- DMW-H1 <1–<10 (19) <5–<5 (19) <0.001–0.01 (19) 0–360 (46) <1–<1 (19) 210–790 (46) <0.02–0.13 (19) NA <1–<1 (19) --; <10 --; <5 --; <0.01 195; 210 --; <1 650; 720 --; <0.1 NA --; <1 DMW-H13 <1–<10 (20) <5–<5 (20) <0.001–0.01 (20) 300–1,260 (46) <1–<1 (20) 260–690 (46) <0.02–0.25 (20) NA <1–<1 (20) --; <10 --; <5 --; <0.01 816; 835 --; <1 510; 560 --; <0.1 NA --; <1 Sedgwick recharge site

Treated stream water <10–<10 (13) <5–<5 (13) <0.001–0.01 (13) <5–10 (48) <1–<1 (13) <5–180 (48) <0.1–0.25 (13) NA <1–<1 (13)

--; <10 --; <5 --; <0.01 --; <5 --; <1 23.2*; <5 --; <0.1 NA --; --

SMW-S11 <1–<10 (15) <5–<5 (15) <0.001–0.01 (15) <5–1370 (52) <1–<1 (15) <5–180 (52) <0.1–0.07 (15) NA <1–<1 (15)

--; <10 --; <5 --; <0.01 73.5*; 20 --; <1 20.7*; <5 --; <0.1 NA --; <1

SMW-S13 <1–<10 (15) <5–<5 (15) <0.001–<0.01 (15) <5–20 (47) <1–<1 (15) <1–30 (47) <0.02–0.1 (15) NA <1–<1 (15)

--; <10 --; <5 --; <0.01 --; <5 --; <1 --; <5 --; <0.1 NA --; --

DMW-S10 <10–<10 (14) <5–<5 (14) <0.001–<0.01 (14) <5–100 (40) <1–<1 (14) 210–250 (40) <0.02–<0.1 (14) NA <1–<1 (14)

--; <10 --; <5 --; <0.01 --; <5 --; <1 232; 230 --; <0.1 NA --; <1

DMW-S14 <1–<10 (13) <5–20 (13) <0.001–0.01 (13) <5–50 (36) <1–<1 (13) 140–200 (36) <0.02–<0.1 (13) NA <1–<1 (13)

--; <10 --; <5 --; <0.01 --; <5 --; <1 155; 155 --; <0.1 NA --; <1
Appendix 10

3

Table A–5. Summary of dissolved trace element concentrations in water samples collected as part of the Equus Beds Groundwater Recharge Project during 

1995–2005.—Continued.

[μg/L, micrograms per liter; SDWR, Secondary Drinking-Water Regulation; MCL, Maximum Contaminant Level; --, not determined; HAL, Health Advisory Level; <, less than; NA, not analyzed. The first set of numbers under each heading, for example 99–3,350, indicates the range in concentration. The number in parentheses () indicates the number of samples collected. The numbers below indicate the average followed by the median. Asterisk * is value estimated by using a log-probability regression to predict the values of data below the reporting level.]

Data-collection site

(fig. 6)

Selenium

(μg/L)

Silver

(μg/L)

Strontium

(μg/L)

Thallium

(μg/L)

Vanadium

(μg/L)

Zinc 

(μg/L)

Dimethylarsinate 

as arsenic 

(μg/L)

Monomethylarsonate 

as arsenic 

(μg/L)

Drinking-water criteria 50 (MCL) 100 (SDWR) 4,000 (HAL) 2 (MCL) -- 2,000 (HAL) -- --

Reporting level 2.0 10.0 1.0 1.7 20.0 5.0 0.1 1.2

Surface-water monitoring sites (Little Arkansas River)

7143672 <2–3 (51) <0.2–23 (52) 0–1,330 (51) <1.7–<1.7 (51) <9–15.8 (51) <3–10 (52) <0.1–0.1 (8) <0.1–0.3 (8)

 (near Halstead) 1.18*; <2 --; <10 454; 260 --; <1.7 7.84*; <20 4.15*; <5 --; <0.1 --; <0.1

7144100 <2–3 (54) <0.2–28 (56) 50–1,280 (55) <1.7–<1.7 (54) <9–26.4 (55) <3–20 (56) <0.1–0.1 (8) <0.1–0.3 (8)

 (near Sedgwick) --; <2 3.47*; <10 348; 220 --; <1.7 7.99*; <20 --; <5 --; <0.1 --; <1.2

Diversion well site near Halstead

Diversion well <2–<2 (31) <10–14 (31) 370–870 (31) <1.7–<1.7 (31) <9–<20 (31) <5–20 (31) --–0.8 (1) --–<0.1 (1)

--; <2 --; <10 590; 590 --; <1.7 --; <20 --; <5 --; -- --; --

EB-145-A1 <2–<2 (18) <0.2–<10 (19) 440–1,070 (18) <1.7–<1.7 (18) <2–<20 (18) <3–0.6 (19) <0.1–<0.6 (5) <0.1–<1.2 (5)

--; <2 --; <10 757; 720 --; <1.7 --; <9 --; <5 --; -- --; --

EB-145-A2 <2–<2 (10) <10–<10 (10) 610–970 (10) <1.7–<1.7 (10) <2–<20 (10) <5–20 (10) <0.1–<0.6 (2) <0.1–<1.2 (2)

--; <2 --; <10 758; 750 --; <1.7 --; <9 --; <5 --; -- --; --

EB-145-A3 <2–<2 (10) <1–<10 (10) 680–1,180 (10) <1.7–<1.7 (10) <2–<20 (10) <5–<5 (10) <0.1–<0.6 (2) <1.2–0.1 (2)

--; <2 --; <10 866; 835 --; <1.7 --; <9 --; <5 --; -- --; --

EB-145-A4 <2–<2 (7) <10–<10 (7) 340–940 (7) <1.7–<1.7 (7) <2–<20 (7) <5–<5 (7) <0.1–0.7 (2) <0.1–<1.2 (2)

--; <2 --; <10 671; 760 --; <1.7 --; <20 --; <5 --; -- --; --

EB-145-A5 <2–<2 (9) <10–<10 (8) 490–940 (8) <1.7–<1.7 (8) <2–<20 (8) <5–<5 (8) 0.2–1.8 (3) <1.2–1.2 (3)

--; <2 --; <10 654; 605 --; <1.7 --; <20 --; <5 --; -- --; --

EB-145-P-D5 <2–<2 (15) <10–<10 (15) 310–740 (15) <1.7–<1.7 (15) <2–<20 (15) <5–10 (15) 0.4–3.2 (5) <1.2–2.2 (5)

--; <2 --; <10 483; 510 --; <1.7 --; <20 --; <5 --; -- --; --

Halstead recharge site

SMW-H4 <2–2 (19) <10–21 (19) 280–620 (19) <1.7–<1.7 (19) <20–37.5 (19) <5–<6 (19) <0.1–<0.6 (3) <0.1–<1.2 (3)

--; <2 --; <10 475; 470 --; <1.7 --; <20 --; <5 --; -- --; --

SMW-H14 <2–4 (20) <10–20 (20) 360–740 (20) <1.7–<1.7 (20) <20–6.2 (20) <5–10 (20) <0.1–<0.6 (3) <0.1–<1.2 (3)

1.35*; <2 --; <10 568; 595 --; <1.7 --; <20 --; <5 --; -- --; --

DMW-H1 <2–<2 (19) <10–21 (19) 300–840 (19) <1.7–1.7 (19) <2–<20 (19) <5–<5 (19) <0.1–0.4 (3) <0.1–<1.2 (3)

--; <2 --; <10 559; 640 --; <1.7 --; <20 --; <5 --; -- --; --

DMW-H13 <2–<2 (20) <10–23 (20) 210–650 (20) <1.7–<1.7 (20) <2–28.6 (20) <5–<5 (20) <0.1–<0.6 (3) <0.1–<1.2 (3)

--; <2 --; <10 433; 530 --; <1.7 --; <20 --; <5 --; -- --; --

Sedgwick recharge site

Treated stream water <2–6 (13) <10–18 (13) 170–690 (13) <1.7–<1.7 (13) <20–29.2 (13) <5–20 (13) NA NA

--; <2 --; <10 349; 280 --; <1.7 --; <20 --; <5 NA NA

SMW-S11 <2–12 (16) <10–28 (15) 350–840 (15) <1.7–<1.7 (16) <2–30.2 (15) <5–<5 (15) <0.1–<0.6 (3) <0.1–<1.2 (3)

5.77*; 4 --; <10 512; 490 --; <1.7 --; <20 --; <5 --; -- --; --

SMW-S13 <2–14 (15) <10–15 (15) <1–650 (15) <1.7–<1.7 (15) <2–20.1 (15) <5–<5 (15) <0.1–<0.6 (3) <0.1–<1.2 (3)

4.29*; <2 --; <10 507*; 490 --; <1.7 --; <20 --; <5 --; -- --; --

DMW-S10 <2–<2 (15) <10–22 (14) 760–1,120 (14) <1.7–<1.7 (15) <20–4.7 (14) <5–<5 (14) <0.1–<0.6 (3) <0.1–<1.2 (3)

--; <2 --; <10 859; 810 --; <1.7 --; <20 --; <5 --; -- --; --

DMW-S14 3–10 (13) <10–23 (13) 570–870 (13) <1.7–1.7 (13) <20–34.4 (13) <5–<5 (13) <0.1–<0.6 (3) <0.1–<1.2 (3)

7.77; 8 --; <10 688; 680 --; <1.7 --; <20 --; <5 --; -- --; --
104 Water Quality in the Equus Beds Aquifer and the Little Arkansas River, South-Central Kansas Table A–5. Summary of dissolved trace element concentrations in water samples collected as part of the Equus Beds Groundwater Recharge Project during 1995–2005.— Continued. [μg/L, micrograms per liter; SDWR, Secondary Drinking-Water Regulation; MCL, Maximum Contaminant Level; --, not determined; HAL, Health Advisory Level; <, less than; NA, not analyzed. The first set of numbers under each heading, for example 99–3,350, indicates the range in concentration. The number in parentheses () indicates the number of samples collected. The numbers below indicate the average followed by the median. Asterisk * is value esti- mated by using a log-probability regression to predict the values of data below the reporting level.] Data-collection site (fig. 6) Aluminum (μg/L) Antimony (μg/L) Arsenate as arsenic (μg/L) Arsenic (μg/L) Arsenite as arsenic (μg/L) Barium (μg/L) Beryllium (μg/L) Boron (μg/L) Cadmium (μg/L) Drinking-water criteria 50–200 (SDWR) 6 (MCL) -- 10 (MCL) -- 2,000 (MCL) 4 (MCL) 1,000 (HAL) 5 (MCL) Reporting level 10.0 2 0.8 1.0 0.1 5.0 1.0 10.0 0.5 Background wells EB-142-A3 <10–<10 (3) <2–<2 (3) <4–11 (45) <1–1.3 (3) <0.2–0.3 (5) 143–155 (3) <1–<1 (3) 40–40 (3) <0.01–<0.1 (3) --; -- --; -- 1.95*; <4 --; -- --; -- --; -- --; -- --; -- --; -- Sedgwick well <10–11 (15) <2–80 (16) NA <1–2 (28) NA 109–141 (15) <1–<1 (15) 30–60 (14) <0.01–0.05 (27) --; <10 --; <2 NA 0.744*; <1 NA 127; 125 --; <1 45; 50 0.024*; 0.02 City well-Sedgwick --–<8 (1) --–<2 (1) 2.3–3.8 (5) --–4.4 (1) 4.8–6.5 (5) --–51 (1) --–<1 (1) --–50 (1) --–<0.1 (1) --; -- --; -- --; -- --; -- --; -- --; -- --; -- --; -- --; -- TH-02-95 <8–<10 (7) <2–<2 (7) 1.3–2.3 (5) 7.3–15.4 (20) 3.1–9.5 (5) 176–190 (7) <1–<1 (7) 30–50 (7) <0.1–<0.5 (7) --; <10 --; <2 --; -- 10; 9.9 --; -- 184; 185 --; <1 40; 40 --; <0.5 TH-06-95 <8–<10 (8) <2–<2 (8) 0.5–0.8 (5) 4.2–14.1 (22) 7.2–7.8 (5) 164–199 (8) <1–<1 (8) 20–40 (8) <0.1–<0.5 (8) --; <10 --; <2 --; -- 7.51; 7.05 --; -- 183; 184 --; <1 27.5; 30 --; <0.5 TH-10-95 <8–<10 (7) <2–<2 (7) NA 6.1–10.9 (22) NA 238–385 (7) <1–<1 (7) 10–30 (7) <0.1–<0.5 (7) --; <10 --; <2 NA 9.15; 9.2 NA 310; 302 --; <1 21.4; 20 --; <0.5 TH-12-95 --–<8 (1) --–<2 (1) NA --–2.6 (1) NA --–112 (1) --–<1 (1) --–40 (1) --–<0.1 (1) --; -- --; -- NA --; -- NA --; -- --; -- --; -- --; -- TH-08-A1 <10–<10 (5) <2–<2 (5) NA 4.8–7.9 (5) NA 102–283 (5) <1–<1 (5) 50–60 (5) <0.1–<0.1 (5) --; -- --; -- NA --; -- NA --; -- --; -- --; -- --; -- TH-08-A2 <10–<10 (3) <2–<2 (3) 1.4–2.2 (4) 2.3–6.8 (3) 7.4–8.7 (4) 166–188 (3) <1–<1 (3) 50–50 (3) <0.1–<0.1 (3) --; -- --; -- --; -- --; -- --; -- --; -- --; -- --; -- --; -- TH-08-A3 <10–<10 (7) <2–<2 (7) --–2.4 (1) 9.3–15.1 (19) --–6.9 (1) 56.9–88.1 (7) <1–<1 (7) 40–60 (7) <0.1–<0.5 (7) --; <10 --; <2 --; -- 11.9; 12 --; -- 70.5; 68.5 --; <1 52.9; 50 --; <0.1 TH-08-A4 --–<10 (1) --–<2 (1) 0.8–2 (4) --–11.5 (1) <0.1–<0.6 (4) --–59.2 (1) --–<1 (1) --–40 (1) --–<0.5 (1) --; -- --; -- --; -- --; -- --; -- --; -- --; -- --; -- --; -- TH-08-A5 <10–<10 (3) <2–<2 (3) 2.5–2.7 (5) <1–2.2 (12) <0.1–<0.6 (5) 80.6–102 (3) <1–<1 (3) 40–50 (3) <0.5–<0.5 (3) --; -- --; -- --; -- 1.61*; 1.7 --; -- --; -- --; -- --; -- --; -- Alta Mills <10–<10 (6) <2–<2 (8) NA 1.9–3.4 (18) NA 305–342 (6) <1–<1 (6) 40–60 (6) <0.1–<0.5 (6) --; <10 --; <2 NA 2.8; 2.9 NA 327; 332 --; <1 48.3; 50 --; <0.5 Aquifer storage and recovery prototype wells DW-TW-01 <10–<10 (6) <2–<2 (6) 10.2–10.8 (6) 10–15.1 (7) <0.6–0.5 (6) 51–58.7 (6) <1–<1 (6) 20–40 (6) <0.5–<0.5 (6) --; <10 --; <2 10.6; 10.7 12.3; 12.1 --; 0.2 55.5; 55.7 --; <1 31.7; 35 --; <0.5 DW-TW-02 <10–<10 (6) <2–<2 (6) 10.1–13.9 (6) 11–21.4 (7) 0.3–1 (6) 35.6–60.2 (6) <1–<1 (6) 20–40 (6) <0.5–<0.5 (6) --; <10 --; <2 11.8; 11.8 13.7; 12 0.6; 0.6 42.8; 40.1 --; <1 28.3; 30 --; <0.5 DW-TW-03 <10–<10 (6) <2–<2 (6) 2.4–6.5 (6) 7.3–17.4 (7) 1.5–9.9 (6) 56–59.7 (6) <1–<1 (6) 20–40 (6) <0.5–<0.5 (6) --; <10 --; <2 5.62; 6.2 9.97; 8.9 3.22; 1.95 57.7; 57.6 --; <1 30; 30 --; <0.5 DW-TW-04 <10–<10 (6) <2–<2 (6) 2.6–4.2 (6) 5.2–11.3 (7) 2.7–4.7 (6) 72–81.9 (6) <1–<1 (6) 20–40 (6) <0.5–<0.5 (6) --; <10 --; <2 3.33; 3.3 7.66; 7.3 3.62; 3.6 76.9; 76.2 --; <1 28.3; 30 --; <0.5 DW-TW-05 <10–<10 (6) <2–<2 (6) 6.5–8.8 (6) 8.3–12.8 (7) 0.7–3.5 (6) 88.5–97.4 (6) <1–<1 (6) 10–40 (6) <0.5–<0.5 (6)

--; <10 --; <2 8.12; 8.5 10.6; 10.4 1.38; 1 93.7; 94.4 --; <1 26.7; 30 --; <0.5

DW-TW-06 <10–<10 (6) <2–<2 (6) 2.9–4.9 (5) 4.4–9.1 (7) 0.6–3.6 (5) 80.8–100 (6) <1–<1 (6) 20–40 (6) <0.5–<0.5 (6)

--; <10 --; <2 --; -- 6.4; 6.2 --; -- 88.3; 87.6 --; <1 30; 30 --; <0.5

DW-TW-07 <10–<10 (6) <2–<2 (6) <0.8–3.4 (5) 2.5–6 (7) <0.6–3.3 (5) 87–104 (6) <1–<1 (6) 30–60 (6) <0.5–<0.5 (6)

--; <10 --; <2 --; -- 4.2; 4 --; -- 94.2; 91.1 --; <1 38.3; 35 --; <0.5

DW-TW-08 <10–<10 (4) <2–<2 (4) 5.3–6.7 (3) 5.6–8.4 (4) 0.6–1.6 (3) 131–148 (4) <1–<1 (4) 30–30 (4) <0.5–<0.5 (4)

--; -- --; -- --; -- --; -- --; -- --; -- --; -- --; -- --; --

DW-TW-09 <10–<10 (4) <2–<2 (4) 4.9–5.7 (3) 4.8–7 (4) <0.6–0.9 (3) 116–120 (4) <1–<1 (4) 30–30 (4) <0.5–<0.5 (4)

--; -- --; -- --; -- --; -- --; -- --; -- --; -- --; -- --; --

RRW-01 <10–<10 (6) <2–<2 (6) 0.9–2 (6) <1–3.2 (7) <0.6–1.7 (6) 178–207 (6) <1–<1 (6) <10–30 (6) <0.5–<0.5 (6)

--; <10 --; <2 1.52; 1.6 2.24*; 2 --; <0.6 193; 195 --; <1 15.8*; 10 --; <0.5

RRW-02 <10–<10 (6) <2–<2 (6) <0.2–1.9 (6) 1.2–4.6 (7) 2.1–2.4 (6) 85–94 (6) <1–<1 (6) 20–40 (6) <0.5–<0.5 (6)

--; <10 --; <2 --; <0.8 2.8; 2.8 2.2; 2.15 90.9; 91.7 --; <1 33.3; 35 --; <0.5

RRW-03 <10–<10 (4) <2–<2 (4) <0.2–<0.8 (4) 4.3–5 (5) 3.7–3.9 (4) 121–161 (4) <1–<1 (4) 20–40 (4) <0.5–<0.5 (4)

--; -- --; -- --; -- --; -- --; -- --; -- --; -- --; -- --; --
Appendix 10

5

Table A–5. Summary of dissolved trace element concentrations in water samples collected as part of the Equus Beds Groundwater Recharge Project during 1995–2005.—

Continued.

[μg/L, micrograms per liter; SDWR, Secondary Drinking-Water Regulation; MCL, Maximum Contaminant Level; --, not determined; HAL, Health Advisory Level; <, less than; NA, not analyzed. The first set of numbers under each heading, for example 99–3,350, indicates the range in concentration. The number in parentheses () indicates the number of samples collected. The numbers below indicate the average followed by the median. Asterisk * is value estimated by using a log-probability regression to predict the values of data below the reporting level.]

Data-collection site

(fig. 6)

Chromium

(μg/L)

Copper

(μg/L)

Cyanide

(μg/L)

Iron

(μg/L)

Lead

(μg/L) 

Manganese

(μg/L)

Mercury

(μg/L)

Molybdenum

(μg/L)

Nickel

(μg/L)

Drinking-water criteria 100 (MCL) 1,300 (MCL) 200 (MCL) 300 (SDWR) 15 (MCL) 50 (SDWR) 2 (MCL) -- 100 (HAL)

Reporting level 10.0 5.0 0.01 10.0 1.0 5.0 0.1 0.1 1.0

Background wells

EB-142-A3 <8–<8 (3) <5–<5 (3) <0.001–<1 (3) 420–480 (3) <1–<1 (3) 120–150 (3) <0.02–<0.02 (3) NA <1–<1 (3)

--; -- --; -- --; -- --; -- --; -- --; -- --; -- NA --; --

Sedgwick well <0.01–<0.5 (15) <8–<10 (15) <5–<5 (15) 540–810 (45) <1–<1 (15) 80–110 (45) <0.02–<0.2 (15) <0.1–<0.6 (5) <1–<3 (15)

--; <0.1 --; <8 --; <5 663; 660 --; <1 96; 100 --; <0.1 --; -- --; <1

City well-Sedgwick --–<1 (1) --–<5 (1) --–<0.01 (1) --–130 (1) --–0 (1) --–520 (1) --–<0.2 (1) NA --–<1 (1)

--; -- --; -- --; -- --; -- --; -- --; -- --; -- NA --; --

TH-02-95 <8–<10 (7) <5–<5 (7) <0.01–<0.01 (7) 280–1,190 (25) <1–<1 (7) 290–340 (25) <0.1–<0.2 (7) NA <1–<1 (7)

--; -- --; <5 --; <0.01 1,060; 1,090 --; <1 312; 310 --; <0.1 NA --; <1

TH-06-95 <1–<10 (8) <5–<5 (8) <0.01–<0.01 (8) 210–1,730 (27) <1–<1 (8) 220–360 (27) <0.1–<0.2 (8) NA <1–<1 (8)

--; <8 --; <5 --; <0.01 1,030; 1,020 --; <1 259; 240 --; <0.1 NA --; <1

TH-10-95 <1–<10 (7) <5–<5 (7) <0.01–<0.01 (7) 390–800 (27) <1–<1 (7) 500–690 (27) <0.1–<0.2 (7) NA <1–<1 (7)

--; <10 --; <5 --; <0.01 453; 440 --; <1 562; 560 --; <0.1 NA --; <1

TH-12-95 --–<8 (1) --–<5 (1) --–<0.01 (1) --–920 (1) --–<1 (1) --–170 (1) --–<0.2 (1) NA --–0 (1)

--; -- --; -- --; -- --; -- --; -- --; -- --; -- NA --; --

TH-08-A1 <8–<8 (5) <5–<5 (5) <0.001–1 (5) <10–1,850 (7) <1–<1 (5) 310–4,320 (7) <0.02–0.05 (5) NA <1–<3 (5)

--; -- --; -- --; -- --; 10 --; -- 934; 360 --; -- NA --; --

TH-08-A2 <8–<10 (3) <5–<5 (3) <0.001–<0.01 (3) <5–<10 (10) <1–<1 (3) 90–620 (10) <0.1–0.03 (3) NA <1–<1 (3)

--; -- --; -- --; -- --; <5 --; -- 278; 250 --; -- NA --; --

TH-08-A3 <8–<10 (7) <5–<5 (7) <0.001–2 (7) 360–700 (23) <1–<1 (7) 700–990 (23) <0.02–<0.1 (7) NA <1–<1 (7)

--; <10 --; <5 --; <0.01 617; 620 --; <1 786; 780 --; <0.1 NA --; --

TH-08-A4 --–<10 (1) --–<5 (1) --–<0.01 (1) --–700 (1) --–<1 (1) --–900 (1) --–<0.1 (1) NA --–<1 (1)

--; -- --; -- --; -- --; -- --; -- --; -- --; -- NA --; --

TH-08-A5 <10–<10 (3) <5–<5 (3) <0.01–<0.01 (3) <5–80 (12) <1–<1 (3) 70–290 (12) <0.1–<0.1 (3) NA --–<1 (3)

--; -- --; -- --; -- 25.5*; 10 --; -- 173; 185 --; -- NA --; --

Alta Mills <10–<10 (6) <5–<5 (6) <0.01–<0.01 (6) <5–300 (23) <1–<1 (6) 0–40 (23) <0.1–<0.1 (6) NA <1–<1 (6)

--; -- --; <5 --; <0.01 --; <5 --; -- 12.4; 10 --; <0.1 NA --; <1

Aquifer storage and recovery prototype wells

DW-TW-01 <1–<10 (6) <5–<5 (6) <0.01–<0.01 (6) <5–<5 (7) <1–<1 (6) 160–180 (7) <0.1–<0.1 (6) NA <1–<1 (6)

--; -- --; <5 --; <0.01 --; <5 --; <1 164; 160 --; <0.1 NA --; <1

DW-TW-02 <1–<10 (6) <5–<5 (6) <0.01–<0.01 (6) <5–<5 (7) <1–<1 (6) 170–230 (7) <0.1–<0.1 (6) NA <1–<1 (6)

--; -- --; <5 --; <0.01 --; <5 --; <1 187; 180 --; <0.1 NA --; <1

DW-TW-03 <1–<10 (6) <5–<5 (6) <0.01–<0.01 (6) <5–<5 (7) <1–<1 (6) 130–150 (7) <0.1–<0.1 (6) NA <1–<1 (6)

--; -- --; <5 --; <0.01 --; <5 --; <1 139; 140 --; <0.1 NA --; <1

DW-TW-04 <1–<10 (6) <5–<5 (6) <0.01–<0.01 (6) 10–20 (7) <1–<1 (6) 150–170 (7) <0.1–<0.1 (6) NA <1–<1 (6)

--; -- --; <5 --; <0.01 12.9; 10 --; <1 154; 150 --; <0.1 NA --; <1

DW-TW-05 <1–<10 (6) <5–<5 (6) <0.01–<0.01 (6) <5–<5 (7) <1–<1 (6) 200–240 (7) <0.1–<0.1 (6) NA <1–<1 (6)

--; -- --; <5 --; <0.01 --; <5 --; <1 207; 200 --; <0.1 NA --; <1

DW-TW-06 <1–<10 (6) <5–<5 (6) <0.01–<0.01 (6) <5–<5 (7) <1–<1 (6) 190–220 (7) <0.1–<0.1 (6) NA <1–<1 (6)

--; -- --; <5 --; <0.01 --; -- --; <1 199; 190 --; <0.1 NA --; --

DW-TW-07 <1–<10 (6) <5–<5 (6) <0.005–<0.01 (6) <5–20 (7) <1–<1 (6) 240–330 (7) <0.1–<0.1 (6) NA <1–<1 (6)

--; -- --; <5 --; <0.01 --; <5 --; <1 269; 250 --; <0.1 NA --; --

DW-TW-08 <1–<1 (4) <5–<5 (4) <0.01–<0.01 (4) <5–<5 (4) <1–<1 (4) 270–280 (4) <0.1–<0.1 (4) NA <1–<1 (4)

--; -- --; -- --; -- --; -- --; -- --; -- --; -- NA --; --

DW-TW-09 <1–<1 (4) <5–<5 (4) <0.01–<0.01 (4) <5–<5 (4) <1–<1 (4) 260–260 (4) <0.1–<0.1 (4) NA <1–<1 (4)

--; -- --; -- --; -- --; -- --; -- --; -- --; -- NA --; --

RRW-01 <1–<10 (6) <5–<5 (6) <0.01–<0.01 (6) <5–470 (7) <1–<1 (6) 40–170 (7) <0.1–<0.1 (6) NA <1–<1 (6)

--; -- --; <5 --; <0.01 --; 20 --; <1 119; 130 --; <0.1 NA --; --

RRW-02 <1–<10 (6) <5–<5 (6) <0.01–<0.01 (6) 0–20 (7) <1–<1 (6) 180–200 (7) <0.1–0.1 (6) NA <1–<1 (6)

--; -- --; <5 --; <0.01 15.7; 20 --; <1 193; 190 --; <0.1 NA --; --

RRW-03 <10–<10 (4) <5–<5 (4) <0.01–<0.01 (4) 50–230 (5) <1–<1 (4) 270–320 (5) <0.1–<0.1 (4) NA <1–<1 (4)

--; -- --; -- --; -- --; -- --; -- --; -- --; -- NA --; --
106 Water Quality in the Equus Beds Aquifer and the Little Arkansas River, South-Central Kansas Table A–5. Summary of dissolved trace element concentrations in water samples collected as part of the Equus Beds Groundwater Recharge Project during 1995–2005.—Continued. [μg/L, micrograms per liter; SDWR, Secondary Drinking-Water Regulation; MCL, Maximum Contaminant Level; --, not determined; HAL, Health Advisory Level; <, less than; NA, not analyzed. The first set of numbers under each heading, for example 99–3,350, indicates the range in concentration. The number in parentheses () indicates the number of samples collected. The numbers below indicate the average followed by the median. Asterisk * is value estimated by using a log-probability regression to predict the values of data below the reporting level.] Data-collection site (fig. 6) Selenium (μg/L) Silver (μg/L) Strontium (μg/L) Thallium (μg/L) Vanadium (μg/L) Zinc (μg/L) Dimethylarsinate as arsenic (μg/L) Monomethylarsonate as arsenic (μg/L) Drinking-water criteria 50 (MCL) 100 (SDWR) 4,000 (HAL) 2 (MCL) -- 2,000 (HAL) -- -- Reporting level 2.0 10.0 1.0 1.7 20.0 5.0 0.6 1.2 Background wells EB-142-A3 <1–<2 (3) <10–<10 (3) 580–610 (3) <1.7–<1.7 (3) <9–<9 (3) <5–<5 (3) NA NA --; -- --; -- --; -- --; -- --; -- --; -- NA NA Sedgwick well <2–2 (16) <1–<10 (15) <0.001–1 (15) 540–860 (15) <2–<20 (15) <3–20 (15) 0.4–0.7 (5) <0.1–<1.2 (5) --; <2 --; <10 --; <0.01 652; 590 --; <9 --; <5 --; -- --; -- City well-Sedgwick --–<2 (1) --–<7 (1) --–700 (1) --–<1.7 (1) --–<9 (1) --–10 (1) NA NA --; -- --; -- --; -- --; -- --; -- --; -- NA NA TH-02-95 <2–<2 (8) <7–<10 (7) 430–600 (7) <1.7–<1.7 (7) <2–<20 (7) <3–10 (7) <0.1–0.4 (5) <0.1–<1.2 (5) --; <2 --; <10 484; 470 --; <1.7 --; <20 --; -- --; -- --; -- TH-06-95 <2–<2 (9) <7–<10 (8) 310–450 (8) <1.7–<1.7 (8) <2–<20 (8) <3–<5 (8) <0.1–0.6 (5) <0.1–0.2 (5) --; <2 --; <10 369; 370 --; <1.7 --; <9 --; <5 --; -- --; -- TH-10-95 <2–2 (8) <7–<10 (7) 220–310 (7) <1.7–<1.7 (7) <2–<20 (7) <3–<5 (7) <0.1–0.7 (5) <0.1–0.2 (5) --; <2 --; <10 267; 280 --; <1.7 --; <20 --; <5 --; -- --; -- TH-12-95 --–<2 (1) --–<7 (1) --–650 (1) --–<1.7 (1) --–<9 (1) --–<3 (1) NA NA --; -- --; -- --; -- --; -- --; -- --; -- NA NA TH-08-A1 <2–<2 (5) <10–<10 (5) 380–520 (5) <1.7–<1.7 (5) <9–14.7 (5) <5–10 (5) NA NA --; -- --; -- --; -- --; -- --; -- --; -- NA NA TH-08-A2 <2–<2 (3) <10–<10 (3) 510–560 (3) <1.7–<1.7 (3) <9–<20 (3) <5–<5 (3) NA NA --; -- --; -- --; -- --; -- --; -- --; -- NA NA TH-08-A3 <2–<2 (7) <10–<10 (7) 410–530 (7) <1.7–<1.7 (7) <2–<20 (7) <5–10 (7) <0.1–0.7 (4) <0.1–0.1 (4) --; <2 --; <10 473; 470 --; <1.7 --; <20 --; <5 --; -- --; -- TH-08-A4 --–<2 (1) --–<10 (1) --–440 (1) --–<1.7 (1) --–<20 (1) --–0 (1) --–<0.1 (1) --–<0.1 (1) --; -- --; -- --; -- --; -- --; -- --; -- --; -- --; -- TH-08-A5 <2–<2 (3) <10–<10 (3) 420–630 (3) <1.7–<1.7 (3) <20–4 (3) <5–<5 (3) <0.1–<0.6 (4) <0.1–<1.2 (4) --; -- --; -- --; -- --; -- --; -- --; -- --; -- --; -- Alta Mills 6–22 (8) <10–<10 (6) 610–780 (6) <1.7–<1.7 (8) <20–7.6 (6) <5–<5 (6) <0.1–<0.6 (5) <0.1–<1.2 (5) 15.5; 16 --; <10 662; 650 --; <1.7 --; <20 --; -- --; -- --; -- Aquifer storage and recovery prototype wells DW-TW-01 <2–<2 (6) <10–<10 (6) 260–280 (6) <1.7–<1.7 (6) <2–<20 (6) <5–<5 (6) <0.1–0.1 (6) <0.1–<1.2 (6) --; <2 --; <10 273; 275 --; <1.7 --; <2 --; -- --; <0.6 --; <1.2 DW-TW-02 <2–<2 (6) <10–<10 (6) 280–290 (6) <1.7–<1.7 (6) <2–<20 (6) <5–<5 (6) <0.1–0.1 (6) <0.1–<1.2 (6) --; <2 --; <10 283; 280 --; <1.7 --; <2 --; -- --; <0.6 --; <1.2 DW-TW-03 <2–<2 (6) <10–<10 (6) 270–290 (6) <1.7–<1.7 (6) <2–<20 (6) <5–<5 (6) <0.6–0.3 (6) <0.1–<1.2 (6) --; <2 --; <10 283; 285 --; <1.7 --; <2 --; <5 --; <0.6 --; <1.2 DW-TW-04 <2–<2 (6) <10–<10 (6) 260–290 (6) <1.7–<1.7 (6) <2–<20 (6) <5–<5 (6) <0.1–0.2 (6) <0.1–0.1 (6) --; <2 --; <10 278; 280 --; <1.7 --; <2 --; -- --; <0.6 --; <1.2 DW-TW-05 <2–<2 (6) <10–<10 (6) 240–260 (6) <1.7–<1.7 (6) <2–<20 (6) <5–<5 (6) <0.1–0.2 (6) <0.1–0.1 (6) --; <2 --; <10 253; 255 --; <1.7 --; <2 --; -- --; <0.6 --; <1.2

DW-TW-06 <2–<2 (6) <10–<10 (6) 250–280 (6) <1.7–<1.7 (6) <2–<20 (6) <5–<5 (6) <0.1–0.2 (6) <0.1–<1.2 (6)

--; <2 --; <10 265; 265 --; <1.7 --; <2 --; -- --; <0.6 --; <1.2

DW-TW-07 <2–<2 (6) <10–<10 (6) 280–760 (6) <1.7–<1.7 (6) <2–<20 (6) <5–<5 (6) <0.1–0.1 (6) <0.1–<1.2 (6)

--; <2 --; <10 393; 325 --; <1.7 --; <2 --; -- --; <0.6 --; <1.2

DW-TW-08 <2–<2 (4) <10–<10 (4) 250–270 (4) <1.7–<1.7 (4) <2–<2 (4) <5–10 (4) <0.6–<0.6 (3) <1.2–<1.2 (3)

--; -- --; -- --; -- --; -- --; -- --; -- --; -- --; --

DW-TW-09 <2–<2 (4) <10–<10 (4) 270–280 (4) <1.7–<1.7 (4) <2–<2 (4) <5–<5 (4) <0.6–<0.6 (3) <1.2–<1.2 (3)

--; -- --; -- --; -- --; -- --; -- --; -- --; -- --; --

RRW-01 <2–<2 (6) <10–<10 (6) 180–210 (6) <1.7–<1.7 (6) <20–11 (6) <5–<5 (6) <0.1–0.1 (6) <0.1–<1.2 (6)

--; <2 --; <10 197; 200 --; <1.7 --; 4.1 --; -- --; <0.6 --; <1.2

RRW-02 <2–<2 (6) <10–<10 (6) 260–290 (6) <1.7–<1.7 (6) <2–<20 (6) <5–<5 (6) <0.1–<0.6 (6) <0.1–<1.2 (6)

--; <2 --; <10 278; 280 --; <1.7 --; <2 --; -- --; <0.6 --; <1.2

RRW-03 <2–<2 (4) <10–<10 (4) 320–410 (4) <1.7–<1.7 (4) <2–<20 (4) <5–<5 (4) <0.1–0.2 (4) <0.1–<1.2 (4)

--; -- --; -- --; -- --; -- --; -- --; -- --; -- --; --
Appendix 10

7

Table A–5. Summary of dissolved trace element concentrations in water samples collected as part of the Equus Beds Groundwater Recharge Project during 1995–2005.—

Continued.

[μg/L, micrograms per liter; SDWR, Secondary Drinking-Water Regulation; MCL, Maximum Contaminant Level; --, not determined; HAL, Health Advisory Level; <, less than; NA, not analyzed. The first set of numbers under each heading, for example 99–3,350, indicates the range in concentration. The number in parentheses () indicates the number of samples collected. The numbers below indicate the average followed by the median. Asterisk * is value estimated 

by using a log-probability regression to predict the values of data below the reporting level.]

Data-collection site

(fig. 6)

Aluminum

(μg/L)

Antimony

(μg/L)

Arsenate as arsenic

(μg/L)

Arsenic

(μg/L)

Arsenite as arsenic

(μg/L)

Barium

(μg/L)

Beryllium

(μg/L)

Boron

(μg/L)

Cadmium

(μg/L)

Drinking-water criteria 50–200 (SDWR) 6 (MCL) -- 10 (MCL) -- 2,000 (MCL) 4 (MCL) 1,000 (HAL) 5 (MCL)

Reporting level 10.0 2 0.8 1.0 0.6 5.0 1.0 10.0 0.5

Shallow index wells

IW-01A <10–<10 (3) <2–<2 (3) <0.2–0.7 (5) <1–<1 (7) <0.1–0.4 (5) 62.7–80.3 (3) <1–<1 (3) <10–10 (3) <0.5–<0.5 (3)

--; -- --; -- --; -- --; <1 --; -- --; -- --; -- --; -- --; --

IW-02A <10–<10 (3) <2–<2 (3) <0.8–0.2 (4) <1–<1 (7) <0.1–<0.6 (4) 82.2–88.7 (3) <1–<1 (3) <10–10 (3) <0.5–<0.5 (3)

--; -- --; -- --; -- --; <1 --; -- --; -- --; -- --; -- --; --

IW-03A <10–<10 (3) <2–<2 (3) 0.7–3.4 (5) 1.3–4.8 (7) 0.7–2.4 (5) 342–427 (3) <1–<1 (3) 30–30 (3) <0.5–<0.5 (3)

--; -- --; -- --; -- 3.09; 3 --; -- --; -- --; -- --; -- --; --

IW-04A <10–<10 (3) <2–<2 (3) 0.5–3.1 (4) 2.8–55 (7) <0.6–2 (4) 53.1–72.2 (3) <1–<1 (3) 170–270 (3) <0.5–<0.5 (3)

--; -- --; -- --; -- 17.1; 4.3 --; -- --; -- --; -- --; -- --; --

IW-05A <10–<10 (3) <2–<2 (3) 0.5–0.6 (4) <1–1.1 (7) <0.1–<0.6 (4) 341–400 (3) <1–<1 (3) 10–20 (3) --–0 (3)

--; -- --; -- --; -- --; <1 --; -- --; -- --; -- --; -- --; --

IW-06A <10–5.3 (4) <2–0.11 (4) 0.6–1.1 (5) <1–2.9 (8) <0.1–0.4 (5) 312–345 (4) <0.06–<1 (4) 30–34 (4) <0.5–0.19 (4)

--; -- --; -- --; -- --; <1 --; -- --; -- --; -- --; -- --; --

IW-07A <10–<10 (3) <2–<2 (3) 3.9–6.3 (4) 9.5–14.4 (7) 4.8–6.1 (4) 202–214 (3) <1–<1 (3) 30–40 (3) <0.5–<0.5 (3)

--; -- --; -- --; -- 11.5; 11.1 --; -- --; -- --; -- --; -- --; --

IW-08A <10–<10 (3) <2–<2 (3) 0.5–0.9 (5) <1–1.1 (7) <0.6–0.5 (5) 88–106 (3) <1–<1 (3) 50–50 (3) <0.5–<0.5 (3)

--; -- --; -- --; -- --; <1 --; -- --; -- --; -- --; -- --; --

IW-09A <10–<10 (3) <2–<2 (3) 0.5–0.8 (4) <1–1.2 (7) <0.1–<0.6 (4) 108–147 (3) <1–<1 (3) 40–60 (3) <0.5–<0.5 (3)

--; -- --; -- --; -- --; <1 --; -- --; -- --; -- --; -- --; --

IW-10A <10–<10 (3) <2–<2 (3) <0.2–<0.8 (4) <1–1.1 (7) <0.1–<0.6 (4) 215–272 (3) <1–<1 (3) 60–70 (3) <0.5–<0.5 (3)

--; -- --; -- --; -- --; <1 --; -- --; -- --; -- --; -- --; --

IW-11A-2 <10–<10 (4) <2–<2 (4) 1.9–2.8 (5) 10.4–14.1 (7) 6.7–9.7 (5) 176–359 (4) <1–<1 (4) 40–50 (4) <0.5–<0.5 (4)

--; -- --; -- --; -- 11.9; 11.6 --; -- --; -- --; -- --; -- --; --

IW-12A <10–5.4 (4) <2–0.6 (4) 3.2–4.1 (6) 3.9–28.7 (8) <0.1–2 (6) 109–141 (4) <0.06–<1 (4) 60–70 (4) <0.5–0.03 (4)

--; -- --; -- 3.65; 3.7 8.13; 5.2 --; 0.4 --; -- --; -- --; -- --; --

IW-13A <10–5.3 (5) <0.05–<2 (5) 1.5–3.8 (5) 5.1–8.2 (8) 2–4.9 (5) 107–120 (5) <0.06–<1 (5) 60–72 (5) <0.5–0.03 (5)

--; -- --; -- --; -- 6.7; 6.45 --; -- --; -- --; -- --; -- --; --

IW-14A <10–51 (4) <2–<2 (4) 1.5–5 (5) 3–8.1 (8) 0.2–1.6 (5) 36–49.3 (4) <1–<1 (4) 80–90 (4) <0.5–<0.5 (4)

--; -- --; -- --; -- 4.41; 4.25 --; -- --; -- --; -- --; -- --; --

IW-15A <10–<10 (3) <2–<2 (3) <0.8–4.9 (4) 11.9–19.1 (7) 7.7–8.9 (4) 66–68 (3) <1–<1 (3) 60–70 (3) <0.5–<0.5 (3)

--; -- --; -- --; -- 14.8; 14.3 --; -- --; -- --; -- --; -- --; --

IW-16A <10–<10 (4) <2–<2 (4) <0.8–1.6 (5) 3.6–6.3 (7) 2.4–4 (5) 150–221 (4) <1–<1 (4) 50–60 (4) <0.5–<0.5 (4)

--; -- --; -- --; -- 4.77; 4.7 --; -- --; -- --; -- --; -- --; --

IW-17A <10–<10 (3) <2–<2 (3) 1.9–3.6 (4) 7.2–11.1 (7) 4.8–6.7 (4) 136–148 (3) <1–<1 (3) 40–50 (3) <0.5–<0.5 (3)

--; -- --; -- --; -- 9.56; 9.8 --; -- --; -- --; -- --; -- --; --

IW-18A <10–<10 (3) <2–<2 (3) <0.2–0.3 (4) <1–<1 (7) <0.1–<0.6 (4) 153–157 (3) <1–<1 (3) 50–70 (3) <0.5–<0.5 (3)

--; -- --; -- --; -- --; <1 --; -- --; -- --; -- --; -- --; --

IW-19A <10–<10 (3) <2–<2 (3) 1.5–2.1 (4) 3.8–5.6 (7) 1.5–1.7 (4) 136–166 (3) <1–<1 (3) 70–90 (3) <0.5–<0.5 (3)

--; -- --; -- --; -- 4.27; 3.9 --; -- --; -- --; -- --; -- --; --

IW-20A <10–<10 (3) <2–<2 (3) 0.8–2.1 (6) 2.9–5.6 (7) 1.3–3 (6) 48.1–54.4 (3) <1–<1 (3) 80–110 (3) <0.5–<0.5 (3)

--; -- --; -- 1.42; 1.4 4.03; 3.8 2.38; 2.65 --; -- --; -- --; -- --; --

IW-21A <10–<10 (4) <2–<2 (4) 0.4–2.6 (5) 2–3.4 (7) 1.3–2.3 (5) 113–145 (4) <1–<1 (4) 50–60 (4) <0.5–<0.5 (4)

--; -- --; -- --; -- 2.67; 2.6 --; -- --; -- --; -- --; -- --; --

IW-22A <10–3.1 (4) <2–0.13 (4) <0.2–0.4 (5) <1–1.7 (8) <0.6–0.6 (5) 151–207 (4) <0.06–<1 (4) 40–70 (4) <0.5–0.05 (4)

--; -- --; -- --; -- --; <1 --; -- --; -- --; -- --; -- --; --

IW-23A <10–<10 (3) <2–<2 (3) 1.3–2.4 (4) 5.7–8.8 (7) 4.9–5.4 (4) 66.4–80.6 (3) <1–<1 (3) 60–80 (3) <0.5–<0.5 (3)

--; -- --; -- --; -- 7.56; 7.8 --; -- --; -- --; -- --; -- --; --

IW-24A <10–5.6 (4) <0.3–<2 (4) <0.8–0.8 (5) <1–<1 (7) <0.1–<0.6 (5) 161–171 (4) <0.06–<1 (4) 40–60 (4) <0.5–0.07 (4)

--; -- --; -- --; -- --; <1 --; -- --; -- --; -- --; -- --; --

IW-25A <10–<10 (3) <2–<2 (3) <0.8–0.5 (4) <1–<1 (7) <0.1–<0.6 (4) 123–133 (3) <1–<1 (3) 40–70 (3) <0.5–<0.5 (3)

--; -- --; -- --; -- --; <1 --; -- --; -- --; -- --; -- --; --

IW-26A <10–<10 (3) <2–<2 (3) <0.8–0.6 (4) <1–<1 (7) <0.1–<0.6 (4) 135–160 (3) <1–<1 (3) 50–70 (3) <0.5–<0.5 (3)

--; -- --; -- --; -- --; <1 --; -- --; -- --; -- --; -- --; --
108 Water Quality in the Equus Beds Aquifer and the Little Arkansas River, South-Central Kansas Table A–5. Summary of dissolved trace element concentrations in water samples collected as part of the Equus Beds Groundwater Recharge Project during 1995–2005.— Continued. [μg/L, micrograms per liter; SDWR, Secondary Drinking-Water Regulation; MCL, Maximum Contaminant Level; --, not determined; HAL, Health Advisory Level; <, less than; NA, not analyzed. The first set of numbers under each heading, for example 99–3,350, indicates the range in concentration. The number in parentheses () indicates the number of samples collected. The numbers below indicate the average followed by the median. Asterisk * is value estimated by using a log-probability regression to predict the values of data below the reporting level.] Data-collection site (fig. 6) Chromium (μg/L) Copper (μg/L) Cyanide (μg/L) Iron (μg/L) Lead (μg/L) Manganese (μg/L) Mercury (μg/L) Molybdenum (μg/L) Nickel (μg/L) Drinking-water criteria 100 (MCL) 1,300 (MCL) 200 (MCL) 300 (SDWR) 15 (MCL) 50 (SDWR) 2 (MCL) -- 100 (HAL) Reporting level 10.0 5.0 0.01 10.0 1.0 5.0 0.1 -- 1.0 Shallow index wells IW-01A <10–<10 (3) <5–<5 (3) <0.01–<0.01 (3) <5–<5 (7) <1–<1 (3) 60–90 (7) <0.1–<0.1 (3) NA --–<1 (3) --; -- --; -- --; -- --; <5 --; -- 78.6; 80 --; -- NA --; -- IW-02A <10–<10 (3) <5–<5 (3) <0.01–<0.01 (3) <5–<5 (7) <1–<1 (3) <5–20 (7) <0.1–<0.1 (3) NA --–<1 (3) --; -- --; -- --; -- --; <5 --; -- --; -- --; -- NA --; -- IW-03A <10–<10 (3) <5–<5 (3) <0.01–<0.01 (3) 2,090–3,040 (7) <1–<1 (3) 950–1,490 (7) <0.1–<0.1 (3) NA <1–<1 (3) --; -- --; -- --; -- 2,410; 2,340 --; -- 1,240; 1,190 --; -- NA --; -- IW-04A <1–<10 (3) <5–<5 (3) <0.01–<0.01 (3) 0–34,500 (7) <1–<1 (3) 100–1,390 (7) <0.1–<0.1 (3) NA --–0 (3) --; -- --; -- --; -- 9,830; 370 --; -- 587; 310 --; -- NA --; -- IW-05A <10–<10 (3) <5–<5 (3) <0.01–<0.01 (3) 10–260 (7) <1–<1 (3) 120–300 (7) <0.1–<0.1 (3) NA --–0 (3) --; -- --; -- --; -- 100; 60 --; -- 220; 220 --; -- NA --; -- IW-06A <10–0.8 (4) <5–0.6 (4) <0.01–<0.01 (3) <5–10 (8) <0.08–<1 (4) 0–30 (8) <0.1–<0.1 (3) --–1.4 (1) 0–4.21 (4) --; -- --; -- --; -- --; <5 --; -- 14.7; 18.9 --; -- --; -- --; -- IW-07A <1–<10 (3) <5–<5 (3) <0.01–<0.01 (3) 40–170 (7) <1–<1 (3) 330–370 (7) <0.1–<0.1 (3) NA <1–<1 (3) --; -- --; -- --; -- 94.3; 90 --; -- 353; 350 --; -- NA --; -- IW-08A <10–<10 (3) <5–<5 (3) <0.01–<0.01 (3) 30–270 (7) <1–<1 (3) 30–110 (7) <0.1–<0.1 (3) NA --–0 (3) --; -- --; -- --; -- 174; 170 --; -- 85.7; 100 --; -- NA --; -- IW-09A <10–<10 (3) <5–<5 (3) <0.01–<0.01 (3) <5–<5 (7) <1–<1 (3) 100–360 (7) <0.1–<0.1 (3) NA --–0 (3) --; -- --; -- --; -- --; <5 --; -- 260; 300 --; -- NA --; -- IW-10A <10–<10 (3) <5–<5 (3) <0.01–<0.01 (3) <5–20 (7) <1–<1 (3) <1–<5 (7) <0.1–<0.1 (3) NA --–<1 (3) --; -- --; -- --; -- --; -- --; -- --; <5 --; -- NA --; -- IW-11A-2 <1–<10 (4) <5–<5 (4) <0.01–<0.01 (4) 370–1270 (7) <1–<1 (4) 240–330 (7) <0.1–<0.1 (4) NA <1–<1 (4) --; -- --; -- --; -- 790; 720 --; -- 304; 310 --; -- NA --; -- IW-12A <0.8–<10 (4) <5–0.8 (4) <0.01–<0.01 (3) 10–80 (9) <0.08–<1 (4) 0–380 (9) <0.1–0.13 (3) --–3.1 (1) 0–1.78 (4) --; -- --; -- --; -- 43.3; 40 --; -- 125; 30 --; -- --; -- --; -- IW-13A <0.8–<10 (5) <5–1.5 (5) <0.01–<0.01 (4) 1,600–2,490 (8) <0.08–<1 (5) 150–190 (8) <0.1–<0.1 (4) --–9.4 (1) <1–1.48 (5) --; -- --; -- --; -- 2,130; 2,180 --; -- 165; 166 --; -- --; -- --; -- IW-14A <1–<10 (4) <5–<5 (4) <0.01–<0.01 (4) 2,440–8,440 (8) <1–<1 (4) 130–350 (8) <0.1–<0.1 (4) NA 0–200 (4) --; -- --; -- --; -- 4,890; 4,410 --; -- 199; 165 --; -- NA --; -- IW-15A <10–<10 (3) <5–<5 (3) <0.01–<0.01 (3) 6,440–8,200 (7) <1–<1 (3) 870–1,040 (7) <0.1–<0.1 (3) NA --–0 (3) --; -- --; -- --; -- 7,060; 6,780 --; -- 957; 950 --; -- NA --; -- IW-16A <10–<10 (4) <5–<5 (4) <0.01–<0.01 (4) 7,540–9,040 (7) <1–<1 (4) 700–780 (7) <0.1–<0.1 (4) NA <1–<1 (4) --; -- --; -- --; -- 8,280; 8,260 --; -- 737; 740 --; -- NA --; -- IW-17A <10–<10 (3) <5–<5 (3) <0.01–<0.01 (3) 1,350–1,940 (7) <1–<1 (3) 130–180 (7) <0.1–<0.1 (3) NA <1–<1 (3) --; -- --; -- --; -- 1,560; 1,520 --; -- 157; 160 --; -- NA --; -- IW-18A <10–<10 (3) <5–<5 (3) <0.01–<0.01 (2) 210–270 (7) <1–<1 (3) 10–30 (7) <0.1–<0.1 (3) NA <1–<1 (3) --; -- --; -- --; -- 251; 260 --; -- 18.6; 20 --; -- NA --; -- IW-19A <10–<10 (3) <5–<5 (3) <0.01–<0.01 (3) 2,440–2,980 (7) <1–<1 (3) 250–340 (7) <0.1–<0.1 (3) NA <1–<1 (3)

--; -- --; -- --; -- 2,710; 2,680 --; -- 317; 330 --; -- NA --; --

IW-20A <10–<10 (3) <5–<5 (3) <0.01–<0.01 (3) 34,900–40,700 (7) <1–<1 (3) 860–1,070 (7) <0.1–<0.1 (3) NA <1–<1 (3)

--; -- --; -- --; -- 37,000; 36,700 --; -- 967; 940 --; -- NA --; --

IW-21A <10–<10 (4) <5–<5 (4) <0.01–<0.01 (4) 6,870–9,130 (7) <1–<1 (4) 380–530 (7) <0.1–<0.1 (4) NA <1–<1 (4)

--; -- --; -- --; -- 7,790; 7,460 --; -- 423; 400 --; -- NA --; --

IW-22A <10–1.4 (4) <5–1 (4) <0.01–<0.01 (3) 78–210 (8) <0.08–<1 (4) 50–90 (8) <0.1–<0.1 (3) --–3.4 (1) <1–1.4 (4)

--; -- --; -- --; -- 151; 170 --; -- 68.2; 65 --; -- --; -- --; --

IW-23A <1–<10 (3) <5–<5 (3) <0.01–<0.01 (3) 800–1,870 (7) <1–<1 (3) 730–960 (7) <0.1–<0.1 (3) NA <1–<1 (3)

--; -- --; -- --; -- 1,590; 1,760 --; -- 890; 930 --; -- NA --; --

IW-24A <0.8–<10 (4) <5–0.5 (4) <0.01–<0.01 (3) <5–<8 (8) <0.08–<1 (4) <1–1.9 (8) <0.1–<0.1 (3) --–2.3 (1) <1–2.9 (4)

--; -- --; -- --; -- --; <5 --; -- --; <5 --; -- --; -- --; --

IW-25A <1–<10 (3) <5–<5 (3) <0.01–<0.01 (3) <5–<5 (7) <1–<1 (3) <1–20 (7) <0.1–<0.1 (3) NA <1–<1 (3)

--; -- --; -- --; -- --; <5 --; -- --; <5 --; -- NA --; --

IW-26A <10–<10 (3) <5–<5 (3) <0.01–<0.01 (3) <5–10 (7) <1–<1 (3) <1–<5 (7) <0.1–<0.1 (3) NA <1–<1 (3)

--; -- --; -- --; -- --; <5 --; -- --; <5 --; -- NA --; --
Appendix 10

9

Table A–5. Summary of dissolved trace element concentrations in water samples collected as part of the Equus Beds Groundwater Recharge Project during 1995–

2005.—Continued.

[μg/L, micrograms per liter; SDWR, Secondary Drinking-Water Regulation; MCL, Maximum Contaminant Level; --, not determined; HAL, Health Advisory Level; <, less than; NA, not analyzed. The first set of numbers under each heading, for example 99–3,350, indicates the range in concentration. The number in parentheses () indicates the number of samples collected. The numbers below indicate the average followed by the median. Asterisk * is 

value estimated by using a log-probability regression to predict the values of data below the reporting level.]

Data-collection site

(fig. 6)

Selenium

(μg/L)

Silver

(μg/L)

Strontium

(μg/L)

Thallium

(μg/L)

Vanadium

(μg/L)

Zinc 

(μg/L)

Dimethylarsinate 

as arsenic 

(μg/L)

Monomethylarsonate 

as arsenic 

(μg/L)

Drinking-water criteria 50 (MCL) 100 (SDWR) 4,000 (HAL) 2 (MCL) -- 2,000 (HAL) -- --

Reporting level 2.0 10.0 1.0 1.7 20.0 5.0 0.6 1.2

Shallow index wells

IW-01A <2–<2 (3) <10–<10 (3) 70–100 (3) <1.7–<1.7 (3) <2–<20 (3) <5–<5 (3) <0.1–0.4 (5) <0.1–0.4 (5)

--; -- --; -- --; -- --; -- --; -- --; -- --; -- --; --

IW-02A <2–<2 (3) <10–<10 (3) 80–90 (3) <1.7–<1.7 (3) <2–<20 (3) <5–<5 (3) <0.1–<0.6 (4) <0.1–<1.2 (4)

--; -- --; -- --; -- --; -- --; -- --; -- --; -- --; --

IW-03A <2–<2 (3) <10–<10 (3) 320–370 (3) <1.7–<1.7 (3) <2–<20 (3) <5–<5 (3) <0.1–0.4 (5) <0.1–0.5 (5)

--; -- --; -- --; -- --; -- --; -- --; -- --; -- --; --

IW-04A <2–<2 (3) <10–<10 (3) 340–430 (3) <1.7–<1.7 (3) <20–6.3 (3) <5–10 (3) <0.1–<0.6 (4) <0.1–<1.2 (4)

--; -- --; -- --; -- --; -- --; -- --; -- --; -- --; --

IW-05A <2–<2 (3) <10–<10 (3) 230–270 (3) <1.7–<1.7 (3) <2–<20 (3) <5–<5 (3) <0.1–0.1 (4) <0.1–0.2 (4)

--; -- --; -- --; -- --; -- --; -- --; -- --; -- --; --

IW-06A 2–3 (4) <1–<10 (4) 360–380 (3) <1.7–<1.7 (3) <20–3.5 (3) <5–1.9 (4) <0.1–0.4 (5) <1.2–0.3 (5)

--; -- --; -- --; -- --; -- --; -- --; -- --; -- --; --

IW-07A <2–<2 (3) <10–<10 (3) 250–260 (3) <1.7–<1.7 (3) <2–<20 (3) <5–<5 (3) <0.1–0.5 (4) <0.1–0.5 (4)

--; -- --; -- --; -- --; -- --; -- --; -- --; -- --; --

IW-08A <2–3 (3) <10–<10 (3) 1,240–1,400 (3) <1.7–<1.7 (3) <20–4.1 (3) 0–10 (3) <0.1–0.3 (5) <0.1–0.3 (5)

--; -- --; -- --; -- --; -- --; -- --; -- --; -- --; --

IW-09A 11–14 (3) <10–<10 (3) 500–500 (3) <1.7–<1.7 (3) <20–7.9 (3) <5–<5 (3) <0.1–<0.6 (4) <0.1–<1.2 (4)

--; -- --; -- --; -- --; -- --; -- --; -- --; -- --; --

IW-10A <2–2 (3) <10–<10 (3) 340–420 (3) <1.7–<1.7 (3) <20–4.5 (3) <5–<5 (3) <0.1–<0.6 (4) <0.1–<1.2 (4)

--; -- --; -- --; -- --; -- --; -- --; -- --; -- --; --

IW-11A-2 <2–<2 (4) <10–<10 (4) 240–430 (4) <1.7–<1.7 (4) <2–<20 (4) <5–<5 (4) <0.1–0.6 (5) <0.1–<1.2 (5)

--; -- --; -- --; -- --; -- --; -- --; -- --; -- --; --

IW-12A <2–<2 (4) <1–<10 (4) 400–560 (3) <1.7–<1.7 (3) <20–6.5 (3) <1–<5 (4) <0.1–<0.6 (6) <0.1–<1.2 (6)

--; -- --; -- --; -- --; -- --; -- --; -- --; <0.1 --; <0.1

IW-13A <2–<2 (4) <1–<10 (5) 1,070–1,520 (4) <1.7–<1.7 (4) <2–<20 (4) <5–1.7 (5) <0.1–<0.6 (5) <0.1–<1.2 (5)

--; -- --; -- --; -- --; -- --; -- --; -- --; -- --; --

IW-14A <2–2 (4) <10–<10 (4) 460–640 (4) <1.7–<1.7 (4) <2–<20 (4) 30–90 (4) <0.1–<0.6 (5) <0.1–<1.2 (5)

--; -- --; -- --; -- --; -- --; -- --; -- --; -- --; --

IW-15A <2–<2 (3) <10–<10 (3) 1,320–1,360 (3) <1.7–<1.7 (3) <2–<20 (3) --–0 (3) <0.1–1 (4) <0.1–<1.2 (4)

--; -- --; -- --; -- --; -- --; -- --; -- --; -- --; --

IW-16A <2–<2 (4) <10–<10 (4) 650–810 (4) <1.7–<1.7 (4) <2–<20 (4) <5–10 (4) <0.1–<0.6 (5) <0.1–<1.2 (5)

--; -- --; -- --; -- --; -- --; -- --; -- --; -- --; --

IW-17A <2–4 (3) <10–<10 (3) 620–640 (3) <1.7–<1.7 (3) <2–<20 (3) <5–<5 (3) <0.1–0.5 (4) <0.1–0.3 (4)

--; -- --; -- --; -- --; -- --; -- --; -- --; -- --; --

IW-18A <2–<2 (3) <10–<10 (3) 1,090–1,130 (3) <1.7–<1.7 (3) <2–<20 (3) --–<5 (3) <0.1–<0.6 (4) <0.1–<1.2 (4)

--; -- --; -- --; -- --; -- --; -- --; -- --; -- --; --

IW-19A <2–<2 (3) <10–<10 (3) 1,600–1,880 (3) <1.7–<1.7 (3) <2–<20 (3) --–0 (3) <0.1–<0.6 (4) <0.1–0.2 (4)

--; -- --; -- --; -- --; -- --; -- --; -- --; -- --; --

IW-20A <2–<2 (3) <10–<10 (3) 1,730–1,800 (3) <1.7–<1.7 (3) <2–<20 (3) 0–10 (3) <0.1–0.1 (6) <0.1–0.3 (6)

--; -- --; -- --; -- --; -- --; -- --; -- --; <0.6 --; <1.2

IW-21A <2–<2 (4) <10–<10 (4) 860–1,290 (4) <1.7–<1.7 (4) <2–<20 (4) <5–<5 (4) <0.1–<0.6 (5) <1.2–0.2 (5)

--; -- --; -- --; -- --; -- --; -- --; -- --; -- --; --

IW-22A <2–<2 (3) <1–<10 (4) 920–1,090 (3) <1.7–<1.7 (3) <2–<20 (3) <5–1 (4) <0.1–<0.6 (5) <0.1–0.2 (5)

--; -- --; -- --; -- --; -- --; -- --; -- --; -- --; --

IW-23A <2–<2 (3) <10–<10 (3) 480–620 (3) <1.7–<1.7 (3) <2–<20 (3) <5–<5 (3) <0.1–0.4 (4) <0.1–0.4 (4)

--; -- --; -- --; -- --; -- --; -- --; -- --; -- --; --

IW-24A <2–4 (4) <0.2–<10 (4) 860–930 (3) <1.7–<1.7 (3) <2–<20 (3) <5–0.9 (4) <0.1–<0.6 (5) <0.1–0.3 (5)

--; -- --; -- --; -- --; -- --; -- --; -- --; -- --; --

IW-25A 54–76 (3) <10–<10 (3) 610–710 (3) <1.7–<1.7 (3) <2–<20 (3) --–<5 (3) <0.1–<0.6 (4) <0.1–0.2 (4)

--; -- --; -- --; -- --; -- --; -- --; -- --; -- --; --

IW-26A 13–39 (3) <10–<10 (3) 720–790 (3) <1.7–<1.7 (3) <2–<20 (3) <5–<5 (3) <0.1–<0.6 (4) <1.2–0.3 (4)

--; -- --; -- --; -- --; -- --; -- --; -- --; -- --; --
110 Water Quality in the Equus Beds Aquifer and the Little Arkansas River, South-Central Kansas Table A–5. Summary of dissolved trace element concentrations in water samples collected as part of the Equus Beds Groundwater Recharge Project during 1995–2005.— Continued. [μg/L, micrograms per liter; SDWR, Secondary Drinking-Water Regulation; MCL, Maximum Contaminant Level; --, not determined; HAL, Health Advisory Level; <, less than; NA, not analyzed. The first set of numbers under each heading, for example 99–3,350, indicates the range in concentration. The number in parentheses () indicates the number of samples collected. The numbers below indicate the average followed by the median. Asterisk * is value estimated by using a log-probability regression to predict the values of data below the reporting level.] Data-collection site (fig. 6) Aluminum (μg/L) Antimony (μg/L) Arsenate as arsenic (μg/L) Arsenic (μg/L) Arsenite as arsenic (μg/L) Barium (μg/L) Beryllium (μg/L) Boron (μg/L) Cadmium (μg/L) Drinking-water criteria 50–200 (SDWR) 6 (MCL) -- 10 (MCL) -- 2,000 (MCL) 4 (MCL) 1,000 (HAL) 5 (MCL) Reporting level 10.0 2.5 0.8 1.0 0.6 5.0 1.0 10.0 0.5 Shallow index wells—Continued IW-27A <10–<10 (3) <2–<2 (3) <0.8–1 (4) <1–<1 (7) <0.1–<0.6 (4) 160–170 (3) <1–<1 (3) 40–60 (3) <0.5–<0.5 (3) --; -- --; -- --; -- --; <1 --; -- --; -- --; -- --; -- --; -- IW-28A <10–<10 (4) <2–<2 (4) 0.7–1.2 (5) <1–1.4 (7) <0.1–<0.6 (5) 56.6–65 (4) <1–<1 (4) 30–60 (4) <0.5–<0.5 (4) --; -- --; -- --; -- --; <1 --; -- --; -- --; -- --; -- --; -- IW-29A <10–5.1 (5) <0.3–<2 (5) 3.4–5.1 (4) 7–11.4 (10) 5.7–7.4 (4) 83.9–112 (5) <0.06–<1 (5) 40–60 (5) <0.5–0.03 (5) --; -- --; -- --; -- 9.67; 10.1 --; -- --; -- --; -- --; -- --; -- IW-30A <10–6.3 (5) <0.3–0.11 (5) <0.2–0.5 (5) <1–<2 (8) <0.1–0.2 (5) 62.8–71.5 (5) <0.06–<1 (5) 30–50 (5) <0.04–<0.5 (5) --; -- --; -- --; -- --; <1 --; -- --; -- --; -- --; -- --; -- IW-31A <10–<10 (3) <2–<2 (3) <0.2–0.4 (4) <1–<1 (7) <0.1–0.2 (4) 141–159 (3) <1–<1 (3) 30–40 (3) <0.5–<0.5 (3) --; -- --; -- --; -- --; <1 --; -- --; -- --; -- --; -- --; -- IW-32A <10–<10 (4) <2–<2 (4) <0.8–0.8 (5) <1–<1 (7) <0.1–0.2 (5) 82.5–112 (4) <1–<1 (4) 30–50 (4) <0.5–<0.5 (4) --; -- --; -- --; -- --; <1 --; -- --; -- --; -- --; -- --; -- IW-33A <10–<10 (3) <2–<2 (3) <0.8–0.4 (4) <1–<1 (7) <0.1–<0.6 (4) 153–171 (3) <1–<1 (3) 30–40 (3) <0.5–<0.5 (3) --; -- --; -- --; -- --; <1 --; -- --; -- --; -- --; -- --; -- IW-34A <10–<10 (4) <2–<2 (4) <0.2–0.8 (5) 2.9–7.5 (7) 2–4.1 (5) 117–137 (4) <1–<1 (4) 40–60 (4) <0.5–<0.5 (4) --; -- --; -- --; -- 4.74; 4 --; -- --; -- --; -- --; -- --; -- IW-35A <10–6.5 (6) <0.3–<2 (6) <0.2–0.3 (5) <1–<2 (10) <0.1–0.1 (5) 40–44.7 (6) <0.06–<1 (6) 110–140 (6) <0.5–0.21 (6) --; <10 --; <2 --; -- --; <1 --; -- 43.2; 44 --; <1 129; 130 --; <0.5 IW-36A <10–6.4 (5) <0.3–<2 (5) <0.2–0.3 (4) <1–<2 (10) <0.1–0.1 (4) 83.7–103 (5) <0.06–<1 (5) 70–90 (5) <0.5–0.04 (5) --; -- --; -- --; -- --; <1 --; -- --; -- --; -- --; -- --; -- IW-37A <10–<10 (3) <2–<2 (3) <0.2–0.5 (5) <1–<1 (7) <0.1–0.1 (5) 381–427 (3) <1–<1 (3) 30–40 (3) <0.5–<0.5 (3) --; -- --; -- --; -- --; <1 --; -- --; -- --; -- --; -- --; -- IW-38A <10–<10 (3) <2–<2 (3) 0.8–1.8 (4) 3.3–5.3 (7) 2.3–2.8 (4) 118–136 (3) <1–<1 (3) 70–80 (3) <0.5–<0.5 (3) --; -- --; -- --; -- 4.01; 3.9 --; -- --; -- --; -- --; -- --; -- Deep index wells IW-01C 36–56 (3) <2–<2 (3) 3.6–4 (5) 12–16.2 (7) 8.2–9.9 (5) 149–152 (3) <1–<1 (3) 20–30 (3) <0.5–<0.5 (3) --; -- --; -- --; -- 13.6; 13 --; -- --; -- --; -- --; -- --; -- IW-02C <10–10 (3) <2–<2 (3) 0.3–0.7 (4) <1–2 (7) 0.7–1.1 (4) 207–221 (3) <1–<1 (3) <10–20 (3) <0.5–<0.5 (3) --; -- --; -- --; -- 1.37*; 1.40 --; -- --; -- --; -- --; -- --; -- IW-03C <10–4.6 (4) <2–0.11 (4) <0.2–1.2 (5) 8.4–10.4 (8) 7.1–7.9 (5) 118–123 (4) <0.06–<1 (4) 20–36 (4) <0.5–0.02 (4) --; -- --; -- --; -- 9.33; 9.2 --; -- --; -- --; -- --; -- --; -- IW-04C <10–<10 (3) <2–<2 (3) 0.5–2 (4) 6.1–10.1 (7) 4.4–6.6 (4) 191–201 (3) <1–<1 (3) 40–40 (3) <0.5–<0.5 (3) --; -- --; -- --; -- 7.5; 7.4 --; -- --; -- --; -- --; -- --; -- IW-05C <10–<10 (3) <2–<2 (3) 0.8–0.9 (4) 4.8–6.6 (7) 3.5–4.3 (4) 271–414 (3) <1–<1 (3) 20–30 (3) <0.5–<0.5 (3) --; -- --; -- --; -- 5.53; 5.4 --; -- --; -- --; -- --; -- --; -- IW-06C <10–<10 (3) <2–<2 (3) 1.9–3.8 (5) 4.8–6.7 (7) 1.6–3.5 (5) 160–167 (3) <1–<1 (3) 20–30 (3) <0.5–<0.5 (3) --; -- --; -- --; -- 5.83; 5.9 --; -- --; -- --; -- --; -- --; -- IW-07C <10–<10 (3) <2–<2 (3) 1.3–1.7 (4) 10.9–13.8 (7) 9.3–11 (4) 53–62.2 (3) <1–<1 (3) 50–50 (3) <0.5–<0.5 (3) --; -- --; -- --; -- 12.4; 12.3 --; -- --; -- --; -- --; -- --; --

IW-08C <10–5.1 (6) <0.6–0.07 (6) 2.6–6 (5) 7–14.9 (11) 4.1–8.1 (5) 993–1,150 (6) <0.1–<1 (6) 41–60 (6) <0.07–0.05 (6)

--; <10 --; <2 --; -- 11.2; 10.6 --; -- 1,090; 1,090 --; -- 50.2; 48 --; --

IW-09C <10–<10 (3) <2–<2 (3) 1.4–4.5 (4) 14–21 (7) 10.7–14.2 (4) 131–144 (3) <1–<1 (3) 30–40 (3) <0.5–<0.5 (3)

--; -- --; -- --; -- 17.3; 16.9 --; -- --; -- --; -- --; -- --; --

IW-10C <10–<10 (3) <2–<2 (3) 0.6–1.6 (4) 8–9.8 (7) 6–6.8 (4) 98.6–109 (3) <1–<1 (3) 30–40 (3) <0.5–<0.5 (3)

--; -- --; -- --; -- 8.73; 8.8 --; -- --; -- --; -- --; -- --; --

IW-11C <10–<10 (4) <2–<2 (4) 3.6–4.7 (5) 8.2–15.2 (7) 6.8–7.6 (5) 70–77.4 (4) <1–<1 (4) 40–50 (4) <0.5–<0.5 (4)

--; -- --; -- --; -- 12.1; 12.1 --; -- --; -- --; -- --; -- --; --

IW-12C <10–<10 (3) <2–<2 (3) 3.2–5.1 (6) 14.4–19.1 (8) 8.7–10.8 (6) 259–277 (3) <1–<1 (3) 60–70 (3) <0.5–<0.5 (3)

--; -- --; -- 4.08; 4.15 16.9; 16.9 9.67; 9.75 --; -- --; -- --; -- --; --

IW-13C <10–<10 (4) <2–<2 (4) 2–4.9 (5) 15.5–22.3 (7) 10.8–13.4 (5) 86–90.4 (4) <1–<1 (4) 50–50 (4) <0.5–<0.5 (4)

--; -- --; -- --; -- 18.3; 17.8 --; -- --; -- --; -- --; -- --; --

IW-14C <10–<10 (4) <2–<2 (4) 0.7–3.9 (5) 14.5–19 (8) 10.5–13.7 (5) 143–151 (4) <1–<1 (4) 60–70 (4) <0.5–<0.5 (4)

--; -- --; -- --; -- 16.7; 16.4 --; -- --; -- --; -- --; -- --; --

IW-15C <10–<10 (3) <2–<2 (3) 4.8–5 (4) 5.9–9.6 (7) 0.5–0.8 (4) 84–86.6 (3) <1–<1 (3) 40–50 (3) <0.5–<0.5 (3)

--; -- --; -- --; -- 7.33; 7.3 --; -- --; -- --; -- --; -- --; --
Appendix 11

1

Table A–5. Summary of dissolved trace element concentrations in water samples collected as part of the Equus Beds Groundwater Recharge Project during 1995–2005.—

Continued.

[μg/L, micrograms per liter; SDWR, Secondary Drinking-Water Regulation; MCL, Maximum Contaminant Level; --, not determined; HAL, Health Advisory Level; <, less than; NA, not analyzed; The first set of numbers under each heading, for example 99–3,350, indicates the range in concentration. The number in parentheses () indicates the number of samples collected. The numbers below indicate the average followed by the median. Asterisk * is value estimated 

by using a log-probability regression to predict the values of data below the reporting level.]

Data-collection site

(fig. 6)

Chromium

(μg/L)

Copper

(μg/L)

Cyanide

(μg/L)

Iron

(μg/L)

Lead

(μg/L) 

Manganese

(μg/L)

Mercury

(μg/L)

Molybdenum

(μg/L)

Nickel

(μg/L)

Drinking-water criteria 100 (MCL) 1,300 (MCL) 200 (MCL) 300 (SDWR) 15 (MCL) 50 (SDWR) 2 (MCL) -- 100 (HAL)

Reporting level 10.0 5.0 0.01 10.0 1.0 5.0 0.1 -- 1.0

Shallow index wells—Continued

IW-27A <10–<10 (3) <5–<5 (3) <0.01–<0.01 (3) <5–<5 (7) <1–<1 (3) <1–<5 (7) <0.1–<0.1 (3) NA <1–<1 (3)

--; -- --; -- --; -- --; <5 --; -- --; -- --; -- NA --; --

IW-28A <10–<10 (4) <5–<5 (4) <0.01–<0.01 (4) <5–<5 (7) <1–<1 (4) <1–<5 (7) <0.1–<0.1 (4) NA --–<1 (4)

--; -- --; -- --; -- --; <5 --; -- --; <1 --; -- NA --; --

IW-29A <0.8–0.8 (5) <5–1.9 (5) <0.01–<0.01 (3) 1,520–5,340 (10) <0.08–0.12 (5) 740–910 (10) <0.1–<0.1 (3) 5.3–5.5 (2) 0–6.16 (5)

--; -- --; -- --; -- 3,830; 3,960 --; -- 828; 810 --; -- --; -- --; --

IW-30A <0.8–<10 (5) <5–1 (5) <0.01–<0.01 (3) <5–20 (9) <0.08–<1 (5) <1–0.5 (9) <0.1–<0.1 (3) 1.4–1.5 (2) <1–2.83 (5)

--; -- --; -- --; -- --; <5 --; -- --; <5 --; -- --; -- --; --

IW-31A <10–<10 (3) <5–<5 (3) <0.01–<0.01 (3) <5–<5 (7) <1–<1 (3) <1–<5 (7) <0.1–<0.1 (3) NA <1–<1 (3)

--; -- --; -- --; -- --; <5 --; -- --; <5 --; -- NA --; --

IW-32A <10–<10 (4) <5–<5 (4) <0.01–<0.01 (4) <5–<5 (7) <1–<1 (4) 10–20 (7) <0.1–<0.1 (4) NA <1–<1 (4)

--; -- --; -- --; -- --; -- --; -- 17.1; 20 --; -- NA --; --

IW-33A <10–<10 (3) <5–<5 (3) <0.01–<0.01 (3) <5–20 (7) <1–<1 (3) <1–<5 (7) <0.1–<0.1 (3) NA <1–<1 (3)

--; -- --; -- --; -- --; <5 --; -- --; <5 --; -- NA --; --

IW-34A <1–<10 (4) <5–<5 (4) <0.01–<0.01 (4) 380–460 (7) <1–<1 (4) 0–50 (7) <0.1–<0.1 (4) NA <1–<1 (4)

--; -- --; -- --; -- 420; 410 --; -- 15.7; 10 --; -- NA --; --

IW-35A <0.8–<10 (6) <5–1.6 (6) <0.01–<0.01 (4) <5–14 (10) <1–3.43 (6) 500–590 (10) <0.1–<0.1 (4) 8.5–9.3 (2) <1–5.15 (6)

--; -- --; <5 --; -- --; <5 --; <1 541; 535 --; -- --; -- --; --

IW-36A <0.8–<10 (5) <5–1.3 (5) <0.01–<0.01 (3) <5–<10 (10) <0.08–0.07 (5) <1–1 (10) <0.1–<0.1 (3) 1.8–2 (2) <1–3.84 (5)

--; -- --; -- --; -- --; <5 --; -- --; <5 --; -- --; -- --; --

IW-37A <10–<10 (3) <5–<5 (3) <0.01–<0.01 (3) <5–<5 (7) <1–<1 (3) <1–<5 (7) <0.1–<0.1 (3) NA --–<1 (3)

--; -- --; -- --; -- --; <5 --; -- --; <5 --; -- NA --; --

IW-38A <10–<10 (3) <5–<5 (3) <0.01–<0.01 (3) 370–970 (7) <1–<1 (3) 510–650 (7) <0.1–<0.1 (3) NA <1–<1 (3)

--; -- --; -- --; -- 659; 690 --; -- 554; 550 --; -- NA --; --

Deep index wells

IW-01C <1–<10 (3) <5–<5 (3) <0.01–<0.01 (3) 20–190 (7) <1–<1 (3) 140–300 (7) <0.1–<0.1 (3) NA <1–<1 (3)

--; -- --; -- --; -- 97.1; 80 --; -- 229; 240 --; -- NA --; --

IW-02C <1–<10 (3) <5–<5 (3) <0.01–<0.01 (3) 180–640 (7) <1–<1 (3) 100–160 (7) <0.1–<0.1 (3) NA <1–<1 (3)

--; -- --; -- --; -- 471; 510 --; -- 124; 120 --; -- NA --; --

IW-03C <0.8–<10 (4) <5–0.2 (4) <0.01–<0.01 (3) 20–50 (8) <0.08–<1 (4) 160–230 (8) <0.1–<0.1 (3) --–3.3 (1) <1–0.65 (4)

--; -- --; -- --; -- 40.8; 40 --; -- 213; 225 --; -- --; -- --; --

IW-04C <10–<10 (3) <5–<5 (3) <0.01–<0.01 (3) 290–510 (7) <1–<1 (3) 490–560 (7) <0.1–<0.1 (3) NA <1–<1 (3)

--; -- --; -- --; -- 411; 430 --; -- 534; 530 --; -- NA --; --

IW-05C <10–<10 (3) <5–<5 (3) <0.01–<0.01 (3) 560–1170 (7) <1–<1 (3) 450–800 (7) <0.1–<0.1 (3) NA <1–<1 (3)

--; -- --; -- --; -- 889; 940 --; -- 669; 710 --; -- NA --; --

IW-06C <1–<10 (3) <5–<5 (3) <0.01–<0.01 (3) 290–720 (7) <1–<1 (3) 210–300 (7) <0.1–<0.1 (3) NA <1–<1 (3)

--; -- --; -- --; -- 509; 510 --; -- 267; 280 --; -- NA --; --

IW-07C <10–<10 (3) <5–<5 (3) <0.01–<0.01 (3) 40–50 (7) <1–<1 (3) 260–320 (7) <0.1–<0.1 (3) NA <1–<1 (3)

--; -- --; -- --; -- 45.7; 50 --; -- 289; 290 --; -- NA --; --

IW-08C <0.8–0.4 (6) <5–1.4 (6) <0.01–<0.01 (3) 14,300–15,800 (11) <0.160–<1 (6) 1,250–1,420 (11) <0.1–<0.1 (3) 2.1–2.1 (3) 0–15 (6)

--; -- --; <5 --; -- 15,200; 15,300 --; -- 1,310; 1,310 --; -- --; -- 5.14; 2.96

IW-09C <10–<10 (3) <5–<5 (3) <0.01–<0.01 (3) 70–120 (7) <1–<1 (3) 380–440 (7) <0.1–<0.1 (3) NA <1–<1 (3)

--; -- --; -- --; -- 92.9; 100 --; -- 416; 420 --; -- NA --; --

IW-10C <1–<10 (3) <5–<5 (3) <0.01–<0.01 (3) 670–900 (7) <1–<1 (3) 240–260 (7) <0.1–<0.1 (3) NA <1–<1 (3)

--; -- --; -- --; -- 800; 790 --; -- 247; 250 --; -- NA --; --

IW-11C <1–<10 (4) <5–<5 (4) <0.01–0.01 (4) 20–140 (7) <1–<1 (4) 90–280 (7) <0.1–<0.1 (4) NA <1–<1 (4)

--; -- --; -- --; -- 75.7; 60 --; -- 221; 240 --; -- NA --; --

IW-12C <10–<10 (3) <5–<5 (3) <0.01–<0.01 (3) 1,590–2,350 (8) <1–<1 (3) 1,180–1,450 (8) <0.1–<0.1 (3) NA <1–<1 (3)

--; -- --; -- --; -- 2,040; 2,050 --; -- 1,360; 1,400 --; -- NA --; --

IW-13C <10–<10 (4) <5–<5 (4) <0.01–<0.01 (4) 1,670–2,210 (7) <1–<1 (4) 490–530 (7) <0.1–<0.1 (4) NA <1–<1 (4)

--; -- --; -- --; -- 2,060; 2,160 --; -- 503; 500 --; -- NA --; --

IW-14C <10–<10 (4) <5–<5 (4) <0.01–<0.01 (4) 1,900–2,240 (8) <1–<1 (4) 970–1,070 (8) <0.1–<0.1 (4) NA <1–<1 (4)

--; -- --; -- --; -- 2,090; 2,100 --; -- 1,020; 1,020 --; -- NA --; --

IW-15C <10–<10 (3) <5–<5 (3) <0.01–<0.01 (3) 10–30 (7) <1–<1 (3) 460–500 (7) <0.1–<0.1 (3) NA <1–<1 (3)

--; -- --; -- --; -- 20; 20 --; -- 481; 480 --; -- NA --; --
112 Water Quality in the Equus Beds Aquifer and the Little Arkansas River, South-Central Kansas Table A–5. Summary of dissolved trace element concentrations in water samples collected as part of the Equus Beds Groundwater Recharge Project during 1995–2005.—Continued. [μg/L, micrograms per liter; SDWR, Secondary Drinking-Water Regulation; MCL, Maximum Contaminant Level; --, not determined; HAL, Health Advisory Level; <, less than; NA, not analyzed. The first set of numbers under each heading, for example 99–3,350, indicates the range in concentration. The number in parentheses () indicates the number of samples collected. The numbers below indicate the average followed by the median. Asterisk * is value estimated by using a log-probability regression to predict the values of data below the reporting level.] Data-collection site (fig. 6) Selenium (μg/L) Silver (μg/L) Strontium (μg/L) Thallium (μg/L) Vanadium (μg/L) Zinc (μg/L) Dimethylarsinate as arsenic (μg/L) Monomethylarsonate as arsenic (μg/L) Drinking-water criteria 50 (MCL) 100 (SDWR) 4,000 (HAL) 2 (MCL) -- 2,000 (HAL) -- -- Reporting level 2.0 10.0 1.0 1.7 20.0 5.0 0.6 1.2 Shallow index wells—Continued IW-27A 5–8 (3) <10–<10 (3) 900–1,010 (3) <1.7–<1.7 (3) <20–2.7 (3) 0–10 (3) <0.1–<0.6 (4) <1.2–0.4 (4) --; -- --; -- --; -- --; -- --; -- --; -- --; -- --; -- IW-28A 5–33 (4) <10–<10 (4) 770–960 (4) <1.7–<1.7 (4) <2–<20 (4) --–0 (4) <0.1–<0.6 (5) <0.1–0.2 (5) --; -- --; -- --; -- --; -- --; -- --; -- --; -- --; -- IW-29A <2–<2 (3) <10–0.2 (5) 1,120–1,620 (3) <1.7–<1.7 (3) <2–<20 (3) 0–1.9 (5) <0.1–0.6 (4) <0.1–0.5 (4) --; -- --; -- --; -- --; -- --; -- --; -- --; -- --; -- IW-30A <2–2 (4) <0.2–<10 (5) 710–780 (3) <1.7–<1.7 (3) <2–<20 (3) <1–10 (5) <0.1–0.1 (5) <0.1–0.4 (5) --; -- --; -- --; -- --; -- --; -- --; -- --; -- --; -- IW-31A <2–2 (3) <10–<10 (3) 760–880 (3) <1.7–<1.7 (3) <2–<20 (3) --–0 (3) <0.1–0.2 (4) <0.1–0.6 (4) --; -- --; -- --; -- --; -- --; -- --; -- --; -- --; -- IW-32A <2–2 (4) <10–<10 (4) 620–1,080 (4) <1.7–<1.7 (4) <2–<20 (4) <5–<5 (4) <0.1–0.1 (5) <0.1–0.4 (5) --; -- --; -- --; -- --; -- --; -- --; -- --; -- --; -- IW-33A 3–5 (3) <10–<10 (3) 550–620 (3) <1.7–<1.7 (3) <2–<20 (3) <5–20 (3) <0.1–<0.6 (4) <0.1–<1.2 (4) --; -- --; -- --; -- --; -- --; -- --; -- --; -- --; -- IW-34A <2–<2 (4) <10–<10 (4) 520–690 (4) <1.7–<1.7 (4) <2–<20 (4) <5–<5 (4) <0.1–0.2 (5) <0.1–0.4 (5) --; -- --; -- --; -- --; -- --; -- --; -- --; -- --; -- IW-35A <2–<2 (4) <10–0.2 (6) 1,000–1,440 (4) <1.7–<1.7 (4) <2–<20 (4) <5–1.3 (6) <0.1–<0.6 (5) <0.1–0.1 (5) --; -- --; <10 --; -- --; -- --; -- --; -- --; -- --; -- IW-36A <2–3 (3) <10–0.3 (5) 960–1,120 (3) <1.7–<1.7 (3) <2–<20 (3) <5–1.6 (5) <0.1–<0.6 (4) <0.1–0.2 (4) --; -- --; -- --; -- --; -- --; -- --; -- --; -- --; -- IW-37A <2–2 (3) <10–<10 (3) 750–890 (3) <1.7–<1.7 (3) <2–<20 (3) --–0 (3) <0.1–<0.6 (5) <0.1–0.2 (5) --; -- --; -- --; -- --; -- --; -- --; -- --; -- --; -- IW-38A <2–<2 (3) <10–<10 (3) 1,280–1,430 (3) <1.7–<1.7 (3) <2–<20 (3) --–0 (3) <0.1–0.2 (4) <1.2–0.4 (4) --; -- --; -- --; -- --; -- --; -- --; -- --; -- --; -- Deep index wells IW-01C <2–<2 (3) <10–<10 (3) 250–310 (3) <1.7–<1.7 (3) <2–<20 (3) <5–<5 (3) <0.1–0.8 (5) <0.1–0.4 (5) --; -- --; -- --; -- --; -- --; -- --; -- --; -- --; -- IW-02C <2–<2 (3) <10–<10 (3) 190–220 (3) <1.7–<1.7 (3) <2–<20 (3) <5–<5 (3) <0.1–0.1 (4) <0.1–0.1 (4) --; -- --; -- --; -- --; -- --; -- --; -- --; -- --; -- IW-03C <2–2 (4) <1–<10 (4) 220–230 (3) <1.7–1.7 (3) <2–<20 (3) <1–<5 (4) <0.1–1.9 (5) <0.1–0.4 (5) --; -- --; -- --; -- --; -- --; -- --; -- --; -- --; -- IW-04C <2–<2 (3) <10–<10 (3) 550–600 (3) <1.7–<1.7 (3) <2–<20 (3) <5–<5 (3) <0.1–0.4 (4) <0.1–0.4 (4) --; -- --; -- --; -- --; -- --; -- --; -- --; -- --; -- IW-05C <2–<2 (3) <10–<10 (3) 420–680 (3) <1.7–<1.7 (3) <2–<20 (3) <5–<5 (3) <0.1–0.5 (4) <0.1–0.2 (4) --; -- --; -- --; -- --; -- --; -- --; -- --; -- --; -- IW-06C <2–<2 (3) <10–<10 (3) 210–230 (3) <1.7–<1.7 (3) <2–<20 (3) <5–<5 (3) <0.1–0.5 (5) <0.1–0.4 (5) --; -- --; -- --; -- --; -- --; -- --; -- --; -- --; -- IW-07C <2–<2 (3) <10–<10 (3) 370–390 (3) <1.7–<1.7 (3) <2–<20 (3) <5–<5 (3) <0.1–0.8 (4) <1.2–0.6 (4)

--; -- --; -- --; -- --; -- --; -- --; -- --; -- --; --

IW-08C <2–<2 (4) <2–1.5 (6) 4,380–4,760 (3) <1.7–<1.7 (3) <2–<20 (3) 0–10 (6) <0.1–0.6 (5) <0.1–0.4 (5)

--; -- --; <10 --; -- --; -- --; -- 4.95; 3.45 --; -- --; --

IW-09C <2–<2 (3) <10–<10 (3) 360–450 (3) <1.7–<1.7 (3) <2–<20 (3) <5–<5 (3) <0.1–0.9 (4) <0.1–0.7 (4)

--; -- --; -- --; -- --; -- --; -- --; -- --; -- --; --

IW-10C <2–<2 (3) <1–<10 (3) 250–270 (3) <1.7–<1.7 (3) <2–<20 (3) <5–<5 (3) <0.1–0.8 (4) <0.1–<1.2 (4)

--; -- --; -- --; -- --; -- --; -- --; -- --; -- --; --

IW-11C <2–<2 (4) <10–<10 (4) 240–260 (4) <1.7–<1.7 (4) <2–<20 (4) <5–<5 (4) <0.1–0.5 (5) <0.1–<1.2 (5)

--; -- --; -- --; -- --; -- --; -- --; -- --; -- --; --

IW-12C <2–<2 (3) <10–<10 (3) 970–1,040 (3) <1.7–<1.7 (3) <2–<20 (3) --–<5 (3) <0.1–0.8 (6) <0.1–0.6 (6)

--; -- --; -- --; -- --; -- --; -- --; -- --; 0.5 --; <1.2

IW-13C <2–2 (4) <10–<10 (4) 1,000–1,230 (4) <1.7–<1.7 (4) <2–<20 (4) <5–<5 (4) <0.1–0.8 (5) <0.1–0.6 (5)

--; -- --; -- --; -- --; -- --; -- --; -- --; -- --; --

IW-14C <2–<2 (4) <10–<10 (4) 1,500–1,880 (4) <1.7–<1.7 (4) <2–<20 (4) 0–10 (4) <0.1–0.8 (5) <0.1–0.5 (5)

--; -- --; -- --; -- --; -- --; -- --; -- --; -- --; --

IW-15C <2–<2 (3) <10–<10 (3) 840–910 (3) <1.7–<1.7 (3) <2–<20 (3) --–0 (3) <0.1–<0.6 (4) <0.1–<1.2 (4)

--; -- --; -- --; -- --; -- --; -- --; -- --; -- --; --
Appendix 11

3

Table A–5. Summary of dissolved trace element concentrations in water samples collected as part of the Equus Beds Groundwater Recharge Project during 1995–2005.—

Continued.

[μg/L, micrograms per liter; SDWR, Secondary Drinking-Water Regulation; MCL, Maximum Contaminant Level; --, not determined; HAL, Health Advisory Level; <, less than; NA, not analyzed. The first set of numbers under each heading, for example 99–3,350, indicates the range in concentration. The number in parentheses () indicates the number of samples collected. The numbers below indicate the average followed by the median. Asterisk * is value estimated 

by using a log-probability regression to predict the values of data below the reporting level.]

Data-collection site

(fig. 6)

Aluminum

(μg/L)

Antimony

(μg/L)

Arsenate as arsenic

(μg/L)

Arsenic

(μg/L)

Arsenite as arsenic

(μg/L)

Barium

(μg/L)

Beryllium

(μg/L)

Boron

(μg/L)

Cadmium

(μg/L)

Drinking-water criteria 50–200 (SDWR) 6 (MCL) -- 10 (MCL) -- 2,000 (MCL) 4 (MCL) 1,000 (HAL) 5 (MCL)

Reporting level 10.0 2.5 0.8 1.0 0.6 5.0 1.0 10.0 0.5

Deep index wells—Continued

IW-16C <10–<10 (4) <2–<2 (4) 0.4–1.5 (5) 5.5–7 (7) 3.8–5 (5) 72.7–83.8 (4) <1–<1 (4) 40–50 (4) <0.5–<0.5 (4)

--; -- --; -- --; -- 6.07; 6 --; -- --; -- --; -- --; -- --; --

IW-17C <10–<10 (3) <2–<2 (3) 1.9–3.5 (4) 20.4–23.9 (7) 16.9–17.5 (4) 64.1–72.7 (3) <1–<1 (3) 40–60 (3) <0.5–<0.5 (3)

--; -- --; -- --; -- 21.6; 21.1 --; -- --; -- --; -- --; -- --; --

IW-18C <10–<10 (3) <2–<2 (3) <0.8–0.5 (4) 1.5–3 (7) 1.2–1.3 (4) 85.8–92.1 (3) <1–<1 (3) 40–50 (3) <0.5–<0.5 (3)

--; -- --; -- --; -- 2.09; 2 --; -- --; -- --; -- --; -- --; --

IW-19C <10–<10 (3) <2–<2 (3) <0.8–0.4 (4) 1.6–2.6 (7) 1.6–2 (4) 67.4–70.5 (3) <1–<1 (3) 50–60 (3) <0.5–<0.5 (3)

--; -- --; -- --; -- 2.26; 2.2 --; -- --; -- --; -- --; -- --; --

IW-20C <10–4.7 (5) <0.3–<2 (5) 2.2–3.6 (5) 10–15.7 (10) 7.9–10.5 (5) 101–127 (5) <0.06–<1 (5) 50–60 (5) <0.5–0.04 (5)

--; -- --; -- --; -- 13; 12.7 --; -- --; -- --; -- --; -- --; --

IW-21C <10–<10 (4) <2–<2 (4) 0.7–3.6 (5) 6.3–9.3 (8) 3.5–6.1 (5) 116–130 (4) <1–<1 (4) 60–60 (4) <0.5–<0.5 (4)

--; -- --; -- --; -- 7.49; 7.1 --; -- --; -- --; -- --; -- --; --

IW-22C <10–<10 (3) <2–<2 (3) 1.6–3 (5) 14.6–17.3 (7) 0.3–12.1 (5) 60.7–64.7 (3) <1–<1 (3) 40–60 (3) <0.5–<0.5 (3)

--; -- --; -- --; -- 15.8; 15.6 --; -- --; -- --; -- --; -- --; --

IW-23C <10–<10 (3) <2–<2 (3) 1.7–2.3 (4) 14.3–16.6 (7) 10.2–11.7 (4) 64.2–67.7 (3) <1–<1 (3) 40–60 (3) <0.5–<0.5 (3)

--; -- --; -- --; -- 15.2; 15 --; -- --; -- --; -- --; -- --; --

IW-24C <10–5.6 (4) <0.3–<2 (4) <0.8–0.6 (5) <1–<1 (7) <0.1–0.1 (5) 42–43.9 (4) <0.06–<1 (4) 50–70 (4) <0.5–0.12 (4)

--; -- --; -- --; -- --; <1 --; -- --; -- --; -- --; -- --; --

IW-25C <10–5.4 (5) <0.3–<2 (5) 0.5–0.8 (4) <1–1 (10) <0.1–0.1 (4) 40.4–49.1 (5) <0.06–<1 (5) 40–64 (5) <0.04–0.03 (5)

--; -- --; -- --; -- --; <1 --; -- --; -- --; -- --; -- --; --

IW-26C <10–<10 (3) <2–<2 (3) 2.2–2.7 (4) 2–2.9 (6) <0.6–12.7 (4) 42.2–44.3 (3) <1–<1 (3) 40–70 (3) <0.5–<0.5 (3)

--; -- --; -- --; -- 2.52; 2.6 --; -- --; -- --; -- --; -- --; --

IW-27C <10–<10 (3) <2–<2 (3) 0.4–1.5 (4) <1–1.6 (7) <0.1–<0.6 (4) 41–48.4 (3) <1–<1 (3) 50–60 (3) <0.5–<0.5 (3)

--; -- --; -- --; -- 1.30*; 1.30 --; -- --; -- --; -- --; -- --; --

IW-28C <10–<10 (4) <2–<2 (4) 1.4–2.1 (5) 1.6–3.1 (7) <0.1–0.2 (5) 43–49.4 (4) <1–<1 (4) 40–70 (4) <0.5–<0.5 (4)

--; -- --; -- --; -- 2.19; 2 --; -- --; -- --; -- --; -- --; --

IW-29C <10–25 (3) <2–<2 (3) 1.5–9.2 (4) 11.6–15.8 (7) <0.6–9.6 (4) 91.9–94 (3) <1–<1 (3) 40–50 (3) <0.5–<0.5 (3)

--; -- --; -- --; -- 13.3; 13.2 --; -- --; -- --; -- --; -- --; --

IW-30C <10–9.1 (6) <0.3–<2 (6) <0.8–0.7 (5) <1–1 (10) <0.1–0.3 (5) 28–36 (6) <0.06–<1 (6) 104–115 (6) <0.5–0.04 (6)

--; <10 --; <10 --; -- --; <1 --; -- 31.7; 30.7 --; <0.06 109; 110 --; <0.5

IW-31C <10–5.2 (4) <2–0.13 (4) 1–1.6 (4) 1–1.7 (8) <0.1–0.3 (4) 33.7–40 (4) <0.06–<1 (4) 50–71 (4) <0.5–0.03 (4)

--; -- --; -- --; -- 1.36; 1.35 --; -- --; -- --; -- --; -- --; --

IW-32C <10–<10 (4) <2–<2 (4) <0.8–1.2 (5) <1–1.2 (7) <0.1–0.2 (5) 100–105 (4) <1–<1 (4) 30–40 (4) <0.5–<0.5 (4)

--; -- --; -- --; -- --; <1 --; -- --; -- --; -- --; -- --; --

IW-33C <10–<10 (3) <2–<2 (3) <0.8–1.1 (4) 1.8–3.4 (7) <0.6–1 (4) 56.8–60.9 (3) <1–<1 (3) 40–50 (3) <0.5–<0.5 (3)

--; -- --; -- --; -- 2.33; 2.2 --; -- --; -- --; -- --; -- --; --

IW-34C <10–<10 (4) <2–<2 (4) 2.2–3.3 (5) 3.2–4.2 (7) <0.1–0.2 (5) 59.1–81 (4) <1–<1 (4) 40–60 (4) <0.5–<0.5 (4)

--; -- --; -- --; -- 3.84; 3.9 --; -- --; -- --; -- --; -- --; --

IW-35C <10–6.4 (6) <0.3–<2 (6) 1.3–2 (5) 1.2–2.2 (10) <0.1–0.1 (5) 74–83 (6) <0.06–<1 (6) 40–60 (6) <0.04–<0.5 (6)

--; <10 --; <2 --; -- 1.75; 1.8 --; -- 80.2; 80.7 --; <1 52.5; 53.5 --; <0.5

IW-36C <10–<10 (3) <2–<2 (3) 0.5–1.2 (4) <1–2.4 (7) <0.1–0.1 (4) 93.9–105 (3) <1–<1 (3) 40–60 (3) <0.5–<0.5 (3)

--; -- --; -- --; -- --; 1.1 --; -- --; -- --; -- --; -- --; --

IW-37C <10–<10 (3) <2–<2 (3) <0.8–1 (5) <1–1.2 (7) <0.1–0.1 (5) 73.9–76.4 (3) <1–<1 (3) 30–40 (3) <0.5–<0.5 (3)

--; -- --; -- --; -- --; <1 --; -- --; -- --; -- --; -- --; --

IW-38C <10–<10 (3) <2–<2 (3) <0.2–0.4 (4) <1–<1 (7) <0.1–0.3 (4) 114–115 (3) <1–<1 (3) 40–50 (3) <0.5–<0.5 (3)

--; -- --; -- --; -- --; <1 --; -- --; -- --; -- --; -- --; --
114 Water Quality in the Equus Beds Aquifer and the Little Arkansas River, South-Central Kansas Table A–5. Summary of dissolved trace element concentrations in water samples collected as part of the Equus Beds Groundwater Recharge Project during 1995–2005.— Continued. [μg/L, micrograms per liter; SDWR, Secondary Drinking-Water Regulation; MCL, Maximum Contaminant Level; --, not determined; HAL, Health Advisory Level; <, less than; NA, not analyzed. The first set of numbers under each heading, for example 99–3,350, indicates the range in concentration. The number in parentheses () indicates the number of samples collected. The numbers below indicate the average followed by the median. Asterisk * is value estimated by using a log-probability regression to predict the values of data below the reporting level.] Data-collection site (fig. 6) Chromium (μg/L) Copper (μg/L) Cyanide (μg/L) Iron (μg/L) Lead (μg/L) Manganese (μg/L) Mercury (μg/L) Molybdenum (μg/L) Nickel (μg/L) Drinking-water criteria 100 (MCL) 1,300 (MCL) 200 (MCL) 300 (SDWR) 15 (MCL) 50 (SDWR) 2 (MCL) -- 100 (HAL) Reporting level 10.0 5.0 0.01 10.0 1.0 5.0 0.1 -- 1.0 Deep index wells—Continued IW-16C <10–<10 (4) <5–<5 (4) <0.01–<0.01 (4) 3,110–5,840 (7) <1–<1 (4) 810–980 (7) <0.1–<0.1 (4) NA <1–<1 (4) --; -- --; -- --; -- 4,420; 4,250 --; -- 883; 860 --; -- NA --; -- IW-17C <10–<10 (3) <5–<5 (3) <0.01–<0.01 (3) 730–960 (7) <1–<1 (3) 330–360 (7) <0.1–<0.1 (3) NA <1–<1 (3) --; -- --; -- --; -- 850; 860 --; -- 347; 350 --; -- NA --; -- IW-18C <10–<10 (3) <5–<5 (3) <0.01–<0.01 (3) 290–590 (7) <1–<1 (3) 260–270 (7) <0.1–<0.1 (3) NA <1–<1 (3) --; -- --; -- --; -- 501; 540 --; -- 264; 260 --; -- NA --; -- IW-19C <10–<10 (3) <5–<5 (3) <0.01–<0.01 (3) 60–140 (7) <1–<1 (3) 510–550 (7) <0.1–<0.1 (3) NA <1–<1 (3) --; -- --; -- --; -- 126; 140 --; -- 526; 520 --; -- NA --; -- IW-20C <0.8–0.5 (5) <5–1.7 (5) <0.01–<0.01 (3) 1,420–2,260 (10) <0.08–<1 (5) 1,100–1,390 (10) <0.1–<0.1 (3) 3.7–4.1 (2) <1–3.69 (5) --; -- --; -- --; -- 1,840; 1,690 --; -- 1,210; 1,180 --; -- --; -- --; -- IW-21C <10–<10 (4) <5–<5 (4) <0.01–<0.01 (4) 7,600–11,500 (8) <1–<1 (4) 1,000–1,210 (8) <0.1–<0.1 (4) NA <1–<1 (4) --; -- --; -- --; -- 10,400; 11,000 --; -- 1,070; 1,070 --; -- NA --; -- IW-22C <1–<10 (3) <5–<5 (3) <0.01–<0.01 (3) 600–1,120 (7) <1–<1 (3) 440–490 (7) <0.1–<0.1 (3) NA <1–<1 (3) --; -- --; -- --; -- 899; 900 --; -- 459; 450 --; -- NA --; -- IW-23C <1–<10 (3) <5–<5 (3) <0.01–<0.01 (3) 430–720 (7) <1–<1 (3) 470–520 (7) <0.1–<0.1 (3) NA <1–<1 (3) --; -- --; -- --; -- 511; 490 --; -- 497; 500 --; -- NA --; -- IW-24C <0.8–<10 (4) <5–0.4 (4) <0.01–<0.01 (3) <5–20 (8) <0.08–<1 (4) 60–120 (8) <0.1–<0.1 (3) --–6.3 (1) <1–1.76 (4) --; -- --; -- --; -- --; <5 --; -- 89.9; 89.7 --; -- --; -- --; -- IW-25C <0.8–<10 (5) <5–0.6 (5) <0.01–<0.01 (3) <5–<10 (10) <1–0.04 (5) 38.4–140 (10) <0.1–<0.1 (3) 6.2–6.3 (2) <1–1.7 (5) --; -- --; -- --; -- --; <5 --; -- 64; 60 --; -- --; -- --; -- IW-26C <10–<10 (3) <5–<5 (3) <0.01–<0.01 (3) <5–<5 (6) <1–<1 (3) 220–240 (6) <0.1–<0.1 (3) NA <1–<1 (3) --; -- --; -- --; -- --; -- --; -- 225; 220 --; -- NA --; -- IW-27C <1–<10 (3) <5–<5 (3) <0.01–<0.01 (3) <5–10 (7) <1–<1 (3) 170–190 (7) <0.1–<0.1 (3) NA <1–<1 (3) --; -- --; -- --; -- --; -- --; -- 180; 180 --; -- NA --; -- IW-28C <10–<10 (4) <5–<5 (4) <0.01–<0.01 (4) <5–<5 (7) <1–<1 (4) 160–210 (7) <0.1–<0.1 (4) NA <1–<1 (4) --; -- --; -- --; -- --; <5 --; -- 179; 170 --; -- NA --; -- IW-29C <10–<10 (3) <5–<5 (3) <0.01–<0.01 (3) 1,320–2,000 (7) <1–<1 (3) 500–610 (7) <0.1–<0.1 (3) NA --–<1 (3) --; -- --; -- --; -- 1,680; 1,720 --; -- 557; 550 --; -- NA --; -- IW-30C <0.8–<10 (6) <5–1.3 (6) <0.01–<0.01 (3) <5–5 (11) <0.08–0.05 (6) 310–340 (11) <0.1–<0.1 (3) 5.7–6 (3) <1–3.19 (6) --; -- --; <5 --; -- --; <5 --; <1 323; 322 --; -- --; -- --; <1 IW-31C <0.8–<10 (4) <5–0.6 (4) <0.01–<0.01 (3) <5–<10 (8) <0.08–<1 (4) 289–320 (8) <0.1–<0.1 (3) --–5.8 (1) <1–1.43 (4) --; -- --; -- --; -- --; -- --; -- 300; 295 --; -- --; -- --; -- IW-32C <10–<10 (4) <5–<5 (4) <0.01–<0.01 (4) <5–<5 (7) <1–<1 (4) 50–70 (7) <0.1–<0.1 (4) NA <1–<1 (4) --; -- --; -- --; -- --; <5 --; -- 57.1; 60 --; -- NA --; -- IW-33C <10–<10 (3) <5–<5 (3) <0.01–<0.01 (3) <5–20 (7) <1–<1 (3) 140–170 (7) <0.1–<0.1 (3) NA <1–<1 (3) --; -- --; -- --; -- --; <5 --; -- 157; 160 --; -- NA --; -- IW-34C <10–<10 (4) <5–<5 (4) <0.01–<0.01 (4) <5–<5 (7) <1–<1 (4) 110–190 (7) <0.1–<0.1 (4) NA <1–<1 (4) --; -- --; -- --; -- --; <5 --; -- 169; 180 --; -- NA --; -- IW-35C <0.8–<10 (6) <5–0.7 (6) <0.01–<0.01 (4) <5–<10 (10) <0.08–0.07 (6) 0–40 (10) <0.1–<0.1 (4) 3.4–3.4 (2) <1–3.33 (6)

--; -- --; <5 --; -- --; <5 --; <1 21.6; 20.5 --; -- --; -- --; <1

IW-36C <10–<10 (3) <5–<5 (3) <0.01–<0.01 (3) <5–<5 (7) <1–<1 (3) <1–30 (7) <0.1–<0.1 (3) NA <1–<1 (3)

--; -- --; -- --; -- --; <5 --; -- --; -- --; -- NA --; --

IW-37C <10–<10 (3) <5–<5 (3) <0.01–<0.01 (3) <5–<5 (7) <1–<1 (3) 310–340 (7) <0.1–<0.1 (3) NA <1–<1 (3)

--; -- --; -- --; -- --; <5 --; -- 326; 330 --; -- NA --; --

IW-38C <10–<10 (3) <5–<5 (3) <0.01–<0.01 (3) 0–10 (7) <1–<1 (3) 290–330 (7) <0.1–<0.1 (3) NA <1–<1 (3)

--; -- --; -- --; -- 7.14; 10 --; -- 306; 300 --; -- NA --; --
Appendix 11

5

Table A–5. Summary of dissolved trace element concentrations in water samples collected as part of the Equus Beds Groundwater Recharge Project during 

1995–2005.—Continued.

[μg/L, micrograms per liter; SDWR, Secondary Drinking-Water Regulation; MCL, Maximum Contaminant Level; --, not determined; HAL, Health Advisory Level; <, less than; NA, not analyzed. The first set of numbers under each heading, for example 99–3,350, indicates the range in concentration. The number in parentheses () indicates the number of samples collected. The numbers below indicate the average followed by the median.Asterisk * is value estimated by using a log-probability regression to predict the values of data below the reporting level.]

Data-collection site

(fig. 6)

Selenium

(μg/L)

Silver

(μg/L)

Strontium

(μg/L)

Thallium

(μg/L)

Vanadium

(μg/L)

Zinc 

(μg/L)

Dimethylarsinate 

as arsenic 

(μg/L)

Monomethylarsonate 

as arsenic 

(μg/L)

Drinking-water criteria 50 (MCL) 100 (SDWR) 4,000 (HAL) 2 (MCL) -- 2,000 (HAL) -- --

Reporting level 2.0 10.0 1.0 1.7 20.0 5.0 0.6 1.2

Deep index wells—Continued

IW-16C <2–<2 (4) <10–<10 (4) 670–900 (4) <1.7–<1.7 (4) <2–<20 (4) <5–<5 (4) <0.1–<0.6 (5) <0.1–<1.2 (5)

--; -- --; -- --; -- --; -- --; -- --; -- --; -- --; --

IW-17C <2–<2 (3) <10–<10 (3) 330–390 (3) <1.7–<1.7 (3) <2–<20 (3) <5–<5 (3) <0.1–1.6 (4) <0.1–1 (4)

--; -- --; -- --; -- --; -- --; -- --; -- --; -- --; --

IW-18C <2–<2 (3) <10–<10 (3) 880–940 (3) <1.7–<1.7 (3) <2–<20 (3) <5–<5 (3) <0.1–<0.6 (4) <0.1–0.1 (4)

--; -- --; -- --; -- --; -- --; -- --; -- --; -- --; --

IW-19C <2–<2 (3) <10–<10 (3) 800–850 (3) <1.7–<1.7 (3) <2–<20 (3) <5–<5 (3) <0.1–<0.6 (4) <1.2–0.2 (4)

--; -- --; -- --; -- --; -- --; -- --; -- --; -- --; --

IW-20C <2–<2 (3) <0.2–<10 (5) 1,330–1,580 (3) <1.7–<1.7 (3) <2–<20 (3) 0–2.2 (5) 0.2–0.6 (5) <0.1–0.4 (5)

--; -- --; -- --; -- --; -- --; -- --; -- --; -- --; --

IW-21C <2–<2 (4) <10–<10 (4) 1,760–1,880 (4) <1.7–<1.7 (4) <2–<20 (4) --–0 (4) <0.1–0.3 (5) <1.2–0.3 (5)

--; -- --; -- --; -- --; -- --; -- --; -- --; -- --; --

IW-22C <2–<2 (3) <10–<10 (3) 570–610 (3) <1.7–1.7 (3) <2–<20 (3) <5–<5 (3) <0.1–0.9 (5) <0.1–0.6 (5)

--; -- --; -- --; -- --; -- --; -- --; -- --; -- --; --

IW-23C <2–<2 (3) <10–<10 (3) 490–540 (3) <1.7–<1.7 (3) <2–<20 (3) <5–<5 (3) <0.1–1 (4) <0.1–0.5 (4)

--; -- --; -- --; -- --; -- --; -- --; -- --; -- --; --

IW-24C <2–<3 (4) <0.2–<10 (4) 600–690 (3) <1.7–<1.7 (3) <2–<20 (3) <1–<5 (4) <0.1–<0.6 (5) <0.1–0.2 (5)

--; -- --; -- --; -- --; -- --; -- --; -- --; -- --; --

IW-25C <2–<2 (3) <0.2–0.2 (5) 790–920 (3) <1.7–<1.7 (3) <20–3.4 (3) <1–0.7 (5) <0.1–<0.6 (4) <0.1–0.2 (4)

--; -- --; -- --; -- --; -- --; -- --; -- --; -- --; --

IW-26C <2–<2 (3) <10–<10 (3) 960–1,090 (3) <1.7–<1.7 (3) <20–4.5 (3) <5–<5 (3) <0.6–0.2 (4) <1.2–0.4 (4)

--; -- --; -- --; -- --; -- --; -- --; -- --; -- --; --

IW-27C <2–<2 (3) <10–<10 (3) 830–930 (3) <1.7–<1.7 (3) <20–2.2 (3) --–<5 (3) <0.1–<0.6 (4) <1.2–0.2 (4)

--; -- --; -- --; -- --; -- --; -- --; -- --; -- --; --

IW-28C <2–<2 (4) <10–<10 (4) 920–1,040 (4) <1.7–<1.7 (4) <2–<20 (4) <5–<5 (4) <0.1–<0.6 (5) <0.1–0.3 (5)

--; -- --; -- --; -- --; -- --; -- --; -- --; -- --; --

IW-29C <2–<2 (3) <10–<10 (3) 760–810 (3) <1.7–<1.7 (3) <2–<20 (3) --–<5 (3) <0.1–0.6 (4) <0.1–0.8 (4)

--; -- --; -- --; -- --; -- --; -- --; -- --; -- --; --

IW-30C <2–<3 (4) <0.2–0.2 (6) 2,050–2,300 (3) <1.7–<1.7 (3) <2–<20 (3) <5–0.9 (6) <0.1–0.2 (5) <0.1–0.6 (5)

--; -- --; <10 --; -- --; -- --; -- --; -- --; -- --; --

IW-31C <2–<2 (3) <1–<10 (4) 1,260–1,430 (3) <1.7–<1.7 (3) <20–2.6 (3) <1–<5 (4) <0.1–0.2 (4) <0.1–0.4 (4)

--; -- --; -- --; -- --; -- --; -- --; -- --; -- --; --

IW-32C 5–7 (4) <10–<10 (4) 620–770 (4) <1.7–<1.7 (4) <2–<20 (4) <5–<5 (4) <0.1–0.1 (5) <0.1–0.5 (5)

--; -- --; -- --; -- --; -- --; -- --; -- --; -- --; --

IW-33C <2–<2 (3) <10–<10 (3) 770–880 (3) <1.7–<1.7 (3) <20–2.1 (3) <5–10 (3) <0.1–<0.6 (4) <0.1–0.2 (4)

--; -- --; -- --; -- --; -- --; -- --; -- --; -- --; --

IW-34C <2–<2 (4) <10–<10 (4) 800–970 (4) <1.7–<1.7 (4) <20–5.6 (4) <5–<5 (4) <0.1–<0.6 (5) <0.1–0.4 (5)

--; -- --; -- --; -- --; -- --; -- --; -- --; -- --; --

IW-35C <2–<2 (4) <10–0.1 (6) 1,010–1,380 (4) <1.7–<1.7 (4) <2–3.5 (4) <5–0.8 (6) <0.1–<0.6 (5) <0.1–0.2 (5)

--; -- --; <10 --; -- --; -- --; -- --; -- --; -- --; --

IW-36C <2–2 (3) <10–<10 (3) 1,210–1,670 (3) <1.7–<1.7 (3) <20–2.1 (3) --–0 (3) <0.1–<0.6 (4) <0.1–0.2 (4)

--; -- --; -- --; -- --; -- --; -- --; -- --; -- --; --

IW-37C 9–12 (3) <10–<10 (3) 650–730 (3) <1.7–<1.7 (3) <20–2.7 (3) <5–<5 (3) <0.1–<0.6 (5) <0.1–0.2 (5)

--; -- --; -- --; -- --; -- --; -- --; -- --; -- --; --

IW-38C <2–<2 (3) <10–<10 (3) 940–1,040 (3) <1.7–<1.7 (3) <2–<20 (3) --–<5 (3) <0.1–<0.6 (4) <0.1–0.3 (4)

--; -- --; -- --; -- --; -- --; -- --; -- --; -- --; --
116 Water Quality in the Equus Beds Aquifer and the Little Arkansas River, South-Central Kansas Table A–6. Summary of detections of organic compounds in water samples collected as part of the Equus Beds Groundwater Recharge Project during 1995–2005. [μg/L, micrograms per liter; MCL, Maximum Contaminant Level; --, not determined; <, less than; NA, not analyzed; HAL, Health Advisory Level; ELISA, enzyme-linked immunosorbent assay; ft, feet. The first set of numbers under each heading, for example 99–3,350, indicates the range in concentration. The number in parentheses () indicates the number of samples collected. The numbers below indicate the average followed by the median. Asterisk * is value estimated by using a log-probability regression to predict the values of data below the reporting level.] Data-collection site (fig. 6) 2,4-D, dissolved (μg/L) 2,4-D, total (μg/L) 2,6-Diethylaniline, dissolved (μg/L)1 2-Chloro-2’,6’-diethyl- acetanilide, dissolved (μg/L) 2-Chloro-4-isopro- pylamno-6-amino-s- triazine, dissolved (μg/L) 2-Chloro-4-isopro- pylamino-6-amino- s-triazine, total (μg/L) 2-Chloro-6-ethyl- amino-4-amino-s- triazine, dissolved (μg/L) 2-Chloro-6-ethyl- amino-4-amino- s-triazine, total (μg/L) 2-Ethyl-6- methylaniline, dissolved (μg/L) Drinking-water criteria 70 (MCL) 70 (MCL) -- -- -- -- -- -- 6 (MCL) Reporting level 0.36 0.01 0.009 0.005 0.05 0.2 0.08 0.2 5.0 07143672 (near Halstead) <0.01–1.07 (4) <0.01–0.18 (5) <0.002–<0.009 (50) <0.005–0.032 (9) <0.006–1.85 (144) <0.2–0.4 (3) <0.05–1.25 (90) <0.2–0.2 (3) <0.004–<0.004 (9) --; -- --; -- --; <0.003 --; <0.005 0.357*; 0.2 --; -- 0.228*; 0.15 --; -- --; <0.004 07144100 (near Sedgwick) <0.04–0.34 (5) <0.01–0.46 (5) <0.002–<0.009 (52) <0.005–0.021 (9) 0.008–5.81 (353) 0.2–0.4 (2) <0.05–1.71 (298) 0.2–0.2 (2) <0.004–<0.004 (9) --; -- --; -- --; <0.003 --; <0.005 0.543; 0.37 --; -- 0.31; 0.23 --; -- --; <0.004 Halstead diversion well <0.04–<0.340 (6) --–<0.01 (1) <0.002–0.003 (30) NA <0.002–0.021 (100) --–<0.2 (1) <0.05–<0.05 (70) --–<0.2 (1) NA --; <0.04 --; -- 0.002*; 0.002 NA 0.004*; <0.05 --; -- --; <0.05 --; -- NA HAL22 <0.04–<0.15 (2) --–<0.01 (1) <0.003–0.007 (14) <0.005–<0.005 (2) <0.002–0.009 (34) NA <0.05–<0.05 (19) NA <0.004–0.002 (2) --; -- --; -- 0.004*; 0.003 --; -- 0.004*; <0.05 NA --; <0.05 NA --; -- HAL33 <0.04–<0.15 (3) <0.01–<0.01 (4) <0.004–0.015 (32) <0.005–<0.005 (2) <0.002–0.17 (95) NA <0.05–0.06 (63) NA 0.007–0.011 (2) --; -- --; -- 0.007*; 0.007 --; -- 0.013*; <0.05 NA --; <0.05 NA --; -- HAL44 NA NA <0.002–0.001 (11) NA <0.002–0.002 (29) NA <0.05–<0.05 (18) NA NA NA NA --; <0.003 NA --; <0.05 NA --; <0.05 NA NA HAL75 <0.04–<0.15 (11) NA <0.002–<0.003 (35) NA <0.05–0.43 (65) NA <0.05–0.09 (30) NA NA --; <0.04 NA --; <0.003 NA 0.031*; 0.005 NA --; <0.05 NA NA HAL86 <0.04–<0.15 (11) NA <0.002–0.003 (35) NA <0.002–0.008 (71) NA <0.05–<0.05 (36) NA NA --; <0.04 NA 0.002*; <0.003 NA 0.004*; <0.05 NA --; <0.05 NA NA Sedgwick treated stream water <0.04–0.09 (4) NA <0.002–<0.003 (13) NA <0.05–0.39 (65) NA <0.05–0.19 (52) NA NA --; -- NA --; <0.003 NA 0.049*; <0.05 NA --; <0.05 NA NA SED57 <0.04–<0.15 (6) NA <0.002–<0.003 (26) NA <0.05–0.21 (70) NA <0.05–0.06 (44) NA NA --; <0.15 NA --; <0.003 NA 0.041*; 0.017 NA --; <0.05 NA NA SED68 <0.04–<0.15 (7) NA <0.002–<0.003 (23) NA <0.002–0.018 (39) NA <0.05–<0.05 (17) NA NA --; <0.15 NA --; <0.003 NA 0.004*; <0.05 NA --; <0.05 NA NA Prototype <0.04–<0.160 (18) NA <0.006–<0.006 (32) <0.005–<0.005 (23) <0.006–<0.05 (53) NA <0.05–<0.08 (19) NA <0.004–<0.004 (23) --; <0.160 NA --; <0.006 --; <0.005 --; <0.006 NA --; <0.05 NA --; <0.004

Background <0.04–<0.04 (2) <0.01–<0.01 (12) <0.002–<0.006 (62) <0.005–<0.005 (15) <0.002–0.58 (82) NA <0.05–0.08 (19) NA <0.004–<0.004 (15)

--; -- --; <0.01 --; <0.003 --; <0.005 0.046*; <0.05 NA --; <0.05 NA --; <0.004

Shallow index wells <0.02–<0.360 (67) NA <0.006–0.003 (66) <0.005–<0.005 (18) <0.006–1.08 (105) NA <0.01–0.28 (59) NA <0.004–<0.004 (18)

--; <0.160 NA 0.002*; <0.006 --; <0.005 0.103*; 0.013 NA 0.034*; <0.05 NA --; <0.004

Deep index wells <0.02–<0.04 (29) NA <0.006–0.002 (29) <0.005–<0.005 (19) <0.006–0.39 (51) NA <0.01–0.07 (41) NA <0.004–<0.004 (19)

--; <0.02 NA --; <0.006 --; <0.005 0.022*; <0.05 NA --; <0.05 NA --; <0.004
Appendix 11

7

Table A–6. Summary of detections of organic compounds in water samples collected as part of the Equus Beds Groundwater Recharge Project during 1995–2005.—Continued[μg/L, micrograms per liter; MCL, Maximum Contaminant Level; --, not determined; <, less than; NA, not analyzed; HAL, Health Advisory Level; ELISA, enzyme-linked immunosorbent assay; ft, feet. The first set of numbers under each heading, for example 99–3,350, indicates the range in concentration. The number in parentheses () indicates the number of samples collected. The numbers below indicate the 

average followed by the median. Asterisk * is value estimated by using a log-probability regression to predict the values of data below the reporting level.]

Data-collection site

(fig. 6)

2-Hydroxy-4-isopropylamino-6-aminos-triazine, dissolved 

(μg/L)1

2-Hydroxy-4-isopropylamino-6-ethylamino-striazine, dissolved 

(μg/L)

3,4-Dichloroaniline, 

dissolved 

(μg/L)

Acetochlor 

ethanesulfonic 

acid, dissolved 

(μg/L)1

Acetochlor 

oxanilic acid, 

dissolved 

(μg/L)1

Acetochlor, 

dissolved 

(μg/L)

Alachlor ethanesulfonic acid, 

dissolved 

(μg/L)1

Alachlor 

oxanilic acid, 

dissolved 

(μg/L)1

Alachlor, 

dissolved 

(μg/L)

Drinking-water criteria -- -- -- -- -- -- -- -- 2.0 (MCL)

Reporting level 0.05 0.05 0.004 0.1 0.1 0.1 0.1 0.1 0.0507143672 

(near Halstead)

<0.03–0.4 (4) <0.025–1.99 (4) <0.004–0.036 (9) <0.1–<0.1 (6) <0.1–<0.1 (6) <0.002–2.2 (140) <0.1–0.3 (6) <0.1–0.3 (6) <0.002–28 (140)

--; -- --; -- --; <0.004 --; <0.1 --; <0.1 --; <0.05 --; <0.1 --; <0.1 0.597*; 0.05

07144100 

(near Sedgwick)

<0.03–0.66 (3) <0.05–1.23 (3) <0.004–0.064 (9) <0.1–<0.1 (5) <0.1–<0.1 (5) <0.002–0.755 (350) <0.1–0.6 (5) 0.1–0.6 (5) <0.002–12.7 (350)

--; -- --; -- 0.018; 0.015 --; -- --; -- 0.022; <0.05 --; -- --; -- 0.523; 0.16

Halstead diversion well NA NA NA --–<0.1 (1) --–<0.1 (1) <0.002–0.003 (100) --–0.2 (1) --–0.1 (1) <0.002–<0.05 (100)

NA NA NA --; -- --; -- --; <0.05 --; -- --; -- --; <0.05

HAL22 --–<0.05 (1) --–<0.05 (1) <0.004–<0.004 (2) --–<0.1 (1) --–<0.1 (1) <0.002–<0.05 (33) --–0.1 (1) --–0.1 (1) <0.002–<0.05 (33)

--; -- --; -- --; -- --; -- --; -- --; <0.05 --; -- --; -- --; <0.05

HAL33 --–<0.05 (1) --–0.91 (1) <0.015–0.019 (2) --–<0.1 (1) --–<0.1 (1) <0.002–<0.05 (94) --–0.1 (1) --–0.1 (1) <0.002–0.24 (94)

--; -- --; -- --; -- --; -- --; -- --; <0.05 --; -- --; -- --; <0.05

HAL44 NA NA NA NA NA <0.002–<0.05 (29) NA NA <0.002–<0.05 (29)

NA NA NA NA NA --; <0.05 NA NA --; <0.05

HAL75 NA NA NA <0.1–0.1 (2) <0.1–<0.1 (2) <0.002–<0.05 (65) <0.1–0.1 (2) <0.1–0.1 (2) <0.002–0.017 (65)

NA NA NA --; -- --; -- --; <0.002 --; -- --; -- --; <0.05

HAL86 NA NA NA <0.1–<0.1 (2) <0.1–<0.1 (2) <0.002–<0.05 (71) 0.2–0.2 (2) 0.1–0.1 (2) <0.002–<0.05 (71)

NA NA NA --; -- --; -- --; <0.05 --; -- --; -- --; <0.05

Sedgwick treated 

stream water

NA NA NA --–<0.1 (1) --–0.1 (1) <0.002–0.022 (65) --–<0.1 (1) --–0.1 (1) <0.002–0.72 (65)

NA NA NA --; -- --; -- --; <0.05 --; -- --; -- 0.037*; <0.05

SED57 NA NA NA <0.1–<0.1 (3) <0.1–<0.1 (3) <0.002–0.009 (70) <0.1–<0.1 (3) <0.1–<0.1 (3) <0.002–0.034 (70)

NA NA NA --; -- --; -- --; <0.05 --; -- --; -- --; <0.05

SED68 NA NA NA <0.1–<0.1 (2) <0.1–<0.1 (2) <0.002–<0.05 (39) <0.1–<0.1 (2) <0.1–<0.1 (2) <0.002–<0.05 (39)

NA NA NA --; -- --; -- --; <0.004 --; -- --; -- --; <0.002

Prototype <0.03–<0.03 (10) <0.025–<0.032 (18) <0.004–<0.004 (23) <0.1–<0.1 (10) <0.1–<0.1 (10) <0.006–<0.05 (43) <0.1–<0.1 (10) <0.1–<0.1 (10) <0.004–<0.05 (43)

--; <0.03 --; <0.025 --; <0.004 --; <0.1 --; <0.1 --; <0.006 --; <0.1 --; <0.1 --; <0.005

Background --–<0.05 (1) --–<0.05 (1) <0.004–<0.004 (15) <0.1–<0.1 (7) <0.1–<0.1 (7) <0.002–0.004 (81) <0.1–0.9 (7) <0.1–<0.1 (7) <0.002–0.017 (81)

--; -- --; -- --; <0.004 --; <0.1 --; <0.1 --; <0.006 --; <0.1 --; <0.1 --; <0.004

Shallow index wells <0.05–<0.05 (10) <0.008–0.159 (40) <0.004–0.017 (18) <0.1–<0.1 (10) <0.1–<0.1 (10) <0.006–<0.05 (95) <0.1–1.5 (10) <0.1–0.1 (10) <0.004–0.013 (95)

--; <0.05 0.012*; <0.032 --; <0.004 --; <0.1 --; <0.1 --; <0.006 0.349*; <0.1 --; <0.1 --; <0.005

Deep index wells <0.05–<0.05 (10) <0.008–0.004 (39) <0.004–<0.004 (19) <0.1–<0.1 (10) <0.1–<0.1 (10) <0.006–<0.05 (41) <0.1–0.2 (10) <0.1–<0.1 (10) <0.004–<0.05 (41)

--; <0.05 --; <0.032 --; <0.004 --; <0.1 --; <0.1 --; <0.006 --; <0.1 --; <0.1 --; <0.005
118 Water Quality in the Equus Beds Aquifer and the Little Arkansas River, South-Central Kansas Table A–6. Summary of detections of organic compounds in water samples collected as part of the Equus Beds Groundwater Recharge Project during 1995–2005.—Continued [μg/L, micrograms per liter; MCL, Maximum Contaminant Level; --, not determined; <, less than; NA, not analyzed; HAL, Health Advisory Level; ELISA, enzyme-linked immunosorbent assay; ft, feet. The first set of numbers under each heading, for example 99–3,350, indicates the range in concentration. The number in parentheses () indicates the number of samples collected. The numbers below indicate the average followed by the median. Asterisk * is value estimated by using a log-probability regression to predict the values of data below the reporting level.] Data-collection site (fig. 6) Alachlor, total (μg/L) Ametryn, dissolved (μg/L) Ametryn, total (μg/L) Aminomethylphos- phonic acid, dissolved (μg/L)1 Atrazine, dissolved (μg/L) Atrazine, total (μg/L) Triazine screen, ELISA, dissolved (μg/L as atrazine) Triazine screen, ELISA, total (μg/L as atrazine) Bentazon, dissolved (μg/L)1 Drinking-water criteria 2.0 (MCL) 60 (HAL) 60 (HAL) -- 3.0 (MCL) 3.0 (MCL) -- -- 20 (HAL) Reporting level 0.1 0.1 0.1 10.0 0.05 0.1 0.1 0.1 0.05 07143672 (near Halstead) <0.1–0.4 (3) <0.05–0.09 (90) <0.1–0.2 (3) 0.3–0.5 (5) 0.028–46.2 (144) 0.3–1.6 (3) <0.1–50 (696) <0.1–3 (10) <0.01–<0.01 (4) --; -- 0.042*; <0.05 --; -- --; -- 5.55; 3.105 --; -- 2.63* ;1 0.657* ;0.2 --; -- 07144100 (near Sedgwick) <0.1–0.2 (2) <0.05–0.92 (298) <0.1–0.1 (2) 0.3–0.5 (5) 0.04–48 (351) 1.1–2.5 (2) 0.1–40 (2,469) <0.1–4 (6) <0.01–<0.05 (5) --; -- --; <0.05 --; -- --; -- 5.922; 3.47 --; -- 4.01 ;2 1.97* ;2 --; -- Halstead diversion well --–<0.1 (1) <0.05–<0.05 (70) --–<0.1 (1) NA <0.05–0.101 (100) --–<0.1 (1) <0.1–0.4 (283) <0.1–0.3 (102) <0.01–<0.01 (6) --; -- --; <0.05 --; -- NA 0.060*; 0.07 --; -- 0.064* ;<0.1 -- ;<0.1 --; <0.01 HAL22 NA <0.05–<0.05 (19) NA --–<0.1 (1) <0.001–0.18 (34) NA <0.1–0.3 (57) <0.1–<0.1 (2) <0.01–<0.01 (2) NA --; <0.05 NA --; -- 0.063*; 0.059 NA 0.078* ;<0.1 -- ;-- --; -- HAL33 NA <0.05–0.05 (63) NA --–<0.1 (1) <0.001–2.2 (95) NA <0.1–3 (128) 0.1–0.2 (4) <0.01–<0.01 (3) NA --; <0.05 NA --; -- 0.210*; 0.05 NA 0.361* ;0.2 -- ;-- --; -- HAL44 NA <0.05–<0.05 (18) NA NA <0.001–0.01 (29) NA <0.1–0.3 (55) NA NA NA --; <0.05 NA NA --; <0.05 NA -- ;<0.1 NA NA HAL75 NA <0.05–<0.05 (30) NA NA <0.05–0.52 (65) NA <0.1–0.5 (92) NA <0.01–<0.01 (11) NA --; <0.05 NA NA 0.059*; 0.038 NA 0.058* ;<0.1 NA --; <0.01 HAL86 NA <0.05–<0.05 (36) NA NA <0.001–0.1 (71) NA <0.1–0.2 (92) NA <0.01–<0.01 (11) NA --; <0.05 NA NA 0.051*; 0.063 NA 0.063* ;<0.1 NA --; <0.01 Sedgwick treated stream water NA <0.05–<0.05 (52) NA NA <0.05–6.71 (65) NA <0.1–7 (228) --–<0.1 (1) <0.01–<0.01 (4) NA --; <0.05 NA NA 0.517*; 0.22 NA 0.265* ;<0.1 -- ;-- --; -- SED57 NA <0.05–<0.05 (44) NA NA <0.05–0.39 (70) NA <0.1–1 (99) NA <0.01–<0.01 (6) NA --; <0.05 NA NA 0.099*; 0.035 NA 0.115* ;<0.1 NA --; <0.01 SED68 NA <0.05–<0.05 (17) NA NA <0.001–0.004 (39) NA <0.1–0.1 (79) NA <0.01–<0.01 (7) NA --; <0.05 NA NA --; <0.007 NA -- ;<0.1 NA --; <0.01 Prototype NA <0.05–<0.05 (11) NA <0.1–<0.1 (10) <0.007–<0.05 (53) NA <0.1–0.8 (76) NA <0.01–<0.05 (18) NA --; <0.05 NA --; <0.1 --; <0.007 NA 0.026* ;<0.1 NA --; <0.05

Background NA <0.05–<0.05 (19) NA <0.1–<0.1 (7) <0.001–1.6 (82) NA <0.01–2 (214) <0.1–<0.1 (13) <0.01–<0.01 (2)

NA --; <0.05 NA --; <0.1 0.056*; <0.05 NA 0.069* ;<0.1 -- ;<0.1 --; --

Shallow index wells NA <0.05–0.09 (29) NA <0.1–0.3 (10) <0.007–1.2 (105) NA <0.1–2 (272) NA <0.01–0.06 (67)

NA --; <0.05 NA --; <0.1 0.048*; 0.005 NA 0.057* ;<0.1 NA --; <0.05

Deep index wells NA <0.05–<0.05 (12) NA <0.1–<10 (10) <0.007–0.07 (51) NA <0.1–0.3 (272) NA <0.01–<0.01 (29)

NA --; <0.05 NA --; <0.1 0.010*; <0.05 NA -- ;<0.1 NA --; <0.01
Appendix 11

9

Table A–6. Summary of detections of organic compounds in water samples collected as part of the Equus Beds Groundwater Recharge Project during 1995–2005.—Continued[μg/L, micrograms per liter; MCL, Maximum Contaminant Level; --, not determined; <, less than; NA, not analyzed; HAL, Health Advisory Level; ELISA, enzyme-linked immunosorbent assay; ft, feet. The first set of numbers under each heading, for example 99–3,350, indicates the range in concentration. The number in parentheses () indicates the number of samples collected. The numbers below indicate the 

average followed by the median. Asterisk * is value estimated by using a log-probability regression to predict the values of data below the reporting level.]

Data-collection site

(fig. 6)

Bis(2-ethylhexyl) 

phthalate, 

total 

(μg/L)

Bromacil, 

dissolved 

(μg/L)

Bromacil, 

total 

(μg/L)

Butylate, 

dissolved 

(μg/L)

Caffeine, 

dissolved 

(μg/L)

Carbaryl, 

dissolved 

(μg/L)1

Carbofuran, 

dissolved 

μg/L)1

Chlorodiamino-striazine, 

dissolved 

(μg/L)1

Chlorodiamino-striazine, 

dissolved 

(μg/L)

Drinking-water criteria -- 90 (HAL) 90 (HAL) 350 (HAL) -- 700 (HAL) 40 (MCL) -- --

Reporting level 5.0 0.09 0.2 0.01 0.018 0.041 0.054 0.05 0.05

07143672 

(near Halstead)

<5–<15 (3) <0.01–<0.04 (4) <0.2–0.5 (3) <0.002–0.007 (41) NA <0.003–0.083 (54) <0.003–0.93 (41) <0.03–0.44 (4) <0.03–0.8 (4)

--; -- --; -- --; -- --; <0.002 NA 0.0134*; <0.041 0.060*; <0.03 --; -- --; --

07144100 

(near Sedgwick)

<5–<5 (3) <0.01–<0.05 (5) 0.6–0.6 (2) <0.002–<0.01 (43) NA <0.003–0.089 (57) <0.003–0.952 (43) <0.03–0.47 (3) <0.03–1.97 (3)

--; -- --; -- --; -- --; <0.002 NA 0.008; <0.041 0.079; 0.009 --; -- --; --

Halstead diversion well --–<5 (1) <0.04–<0.04 (6) --–<0.2 (1) <0.002–<0.002 (30) NA <0.003–<0.041 (36) <0.003–<0.02 (30) NA NA

--; -- --; <0.04 --; -- --; <0.002 NA --; <0.003 --; <0.003 NA NA

HAL22 --–<5 (1) <0.04–<0.130 (2) NA <0.002–<0.002 (12) NA <0.003–<0.041 (16) <0.003–0.004 (12) --–<0.05 (1) --–<0.05 (1)

--; -- --; -- NA --; <0.002 NA --; <0.003 --; <0.003 --; -- --; --

HAL33 <5–<5 (4) <0.04–<0.180 (3) NA <0.002–0.008 (30) NA <0.003–<0.046 (35) <0.003–0.1 (30) --–<0.05 (1) --–<0.05 (1)

--; -- --; -- NA 0.001*; <0.002 NA --; <0.003 0.006*; <0.003 --; -- --; --

HAL44 NA NA NA <0.002–<0.002 (11) NA <0.003–<0.041 (11) <0.003–<0.02 (11) NA NA

NA NA NA --; <0.002 NA --; <0.003 --; <0.003 NA NA

HAL75 NA <0.04–<0.04 (11) NA <0.002–<0.002 (35) NA <0.003–<0.041 (46) <0.003–<0.02 (35) NA NA

NA --; <0.04 NA --; <0.002 NA --; <0.003 --; <0.003 NA NA

HAL86 NA <0.04–<0.04 (11) NA <0.002–<0.002 (35) NA <0.003–<0.041 (46) <0.003–<0.02 (35) NA NA

NA --; <0.04 NA --; <0.002 NA --; <0.003 --; <0.003 NA NA

Sedgwick treated 

stream water

NA <0.04–0.07 (4) NA <0.002–<0.002 (13) NA <0.003–0.016 (17) <0.003–0.211 (13) NA NA

NA --; -- NA --; <0.002 NA --; <0.003 --; <0.008 NA NA

SED57 NA <0.04–<0.04 (6) NA <0.002–<0.002 (26) NA <0.003–<0.041 (32) <0.003–0.054 (26) NA NA

NA --; <0.04 NA --; <0.002 NA --; <0.003 --; <0.003 NA NA

SED68 NA <0.04–<0.04 (7) NA <0.002–<0.002 (23) NA <0.003–<0.041 (30) <0.003–<0.02 (23) NA NA

NA --; <0.04 NA --; <0.002 NA --; <0.003 --; <0.003 NA NA

Prototype NA <0.02–<0.09 (18) NA <0.002–<0.002 (9) <0.018–<0.018 (8) <0.02–<0.08 (50) <0.02–<0.02 (9) <0.03–<0.03 (10) <0.03–<0.04 (18)

NA --; <0.09 NA --; <0.002 --; <0.018 --; <0.041 --; <0.02 --; <0.03 --; <0.03

Background <5–<5 (12) <0.04–<0.04 (2) NA <0.002–<0.008 (47) NA <0.003–<0.046 (64) <0.003–<0.02 (47) --–<0.05 (1) --–<0.05 (1)

--; <5 --; -- NA --; <0.002 NA --; <0.041 --; <0.003 --; -- --; --

Shallow index wells --–3 (1) <0.02–<0.450 (61) NA <0.002–<0.002 (48) <0.01–0.007 (28) <0.02–<0.08 (127) <0.02–<0.02 (48) <0.05–0.17 (10) <0.01–0.05 (38)

--; -- --; <0.09 NA --; <0.002 --; <0.01 --; <0.041 --; <0.02 --; <0.05 --; <0.04

Deep index wells NA <0.02–<0.03 (29) NA <0.002–<0.002 (10) <0.01–0.004 (27) <0.02–<0.041 (58) <0.02–<0.02 (10) <0.05–<0.05 (10) <0.01–<0.05 (37)

NA --; <0.03 NA --; <0.002 --; <0.01 --; <0.041 --; <0.02 --; <0.05 --; <0.04
120 Water Quality in the Equus Beds Aquifer and the Little Arkansas River, South-Central Kansas Table A–6. Summary of detections of organic compounds in water samples collected as part of the Equus Beds Groundwater Recharge Project during 1995–2005.—Continued [μg/L, micrograms per liter; MCL, Maximum Contaminant Level; --, not determined; <, less than; NA, not analyzed; HAL, Health Advisory Level; ELISA, enzyme-linked immunosorbent assay; ft, feet. The first set of numbers under each heading, for example 99–3,350, indicates the range in concentration. The number in parentheses () indicates the number of samples collected. The numbers below indicate the average followed by the median. Asterisk * is value estimated by using a log-probability regression to predict the values of data below the reporting level.] Data-collection site (fig. 6) Chlorotetracycline, dissolved (μg/L) Chlorothalonil, dissolved (μg/L)1 Chlorpyrifos, dissolved (μg/L) Cyanazine acid, dissolved (μg/L) Cyanazine amide, dissolved (μg/L) Cyanazine, dissolved (μg/L) Cyanazine, total (μg/L) Dimethyl tetrachlo- roterephthalate, dissolved (μg/L)1 Deethyl cyanazine acid, dissolved (μg/L) Drinking-water criteria -- 500 (HAL) 20 (HAL) -- -- 1.0 (HAL) 1.0 (HAL) -- -- Reporting level 0.2 0.48 0.005 0.05 0.05 0.05 0.2 0.004 0.05 07143672 (near Halstead) <0.2–<0.2 (3) <0.01–<0.04 (4) <0.004–0.004 (50) <0.03–<0.05 (4) <0.03–0.06 (94) <0.004–0.53 (135) <0.2–0.4 (3) <0.002–0.011 (50) <0.03–<0.05 (4) --; -- --; -- --; <0.004 --; -- --; <0.05 0.034*; <0.05 --; -- 0.001*; <0.003 --; -- 07144100 (near Sedgwick) <0.2–<0.2 (3) <0.01–0.09 (5) <0.004–<0.025 (52) <0.03–<0.05 (3) <0.03–0.18 (284) <0.004–2.07 (342) <0.2–0.3 (2) <0.002–0.005 (52) <0.03–<0.05 (3) --; -- --; -- --; <0.004 --; -- --; <0.05 0.035; <0.05 --; -- 0.001; <0.003 --; -- Halstead diversion well NA <0.04–<0.480 (6) <0.004–<0.005 (30) NA <0.05–<0.05 (61) <0.004–<0.05 (100) --–<0.2 (1) <0.002–<0.003 (30) NA NA --; <0.04 --; <0.004 NA --; <0.05 --; <0.05 --; -- --; <0.002 NA HAL22 --–<0.2 (1) <0.04–<0.480 (2) <0.004–<0.005 (14) --–<0.05 (1) <0.05–<0.05 (20) <0.004–0.07 (32) NA <0.002–<0.003 (14) --–<0.05 (1) --; -- --; -- --; <0.004 --; -- --; <0.05 --; <0.05 NA --; <0.002 --; -- HAL33 --–<0.2 (1) <0.04–<0.480 (3) <0.004–<0.005 (32) --–<0.05 (1) <0.05–<0.05 (64) <0.004–<0.05 (93) NA <0.002–<0.004 (32) --–<0.05 (1) --; -- --; -- --; <0.004 --; -- --; <0.05 --; <0.05 NA --; <0.002 --; -- HAL44 NA NA <0.004–<0.005 (11) NA <0.05–<0.05 (18) <0.004–<0.05 (29) NA <0.002–<0.003 (11) NA NA NA --; <0.004 NA --; <0.05 --; <0.05 NA --; <0.002 NA HAL75 NA <0.04–<0.480 (11) <0.004–<0.005 (35) NA <0.05–<0.05 (30) <0.004–0.74 (65) NA <0.002–<0.003 (35) NA NA --; <0.04 --; <0.004 NA --; <0.05 --; <0.004 NA --; <0.002 NA HAL86 NA <0.04–0.29 (11) <0.004–<0.005 (35) NA <0.05–<0.05 (35) <0.004–<0.05 (71) NA <0.002–<0.003 (35) NA NA --; <0.04 --; <0.004 NA --; <0.05 --; <0.05 NA --; <0.002 NA Sedgwick treated stream water NA <0.04–<0.480 (4) <0.004–<0.005 (13) NA <0.05–<0.05 (52) <0.004–<0.05 (65) NA <0.002–<0.003 (13) NA NA --; -- --; <0.004 NA --; <0.05 --; <0.05 NA --; <0.002 NA SED57 NA <0.04–0.02 (6) <0.004–0.001 (26) NA <0.05–<0.05 (44) <0.004–0.008 (70) NA <0.002–<0.003 (26) NA NA --; <0.480 --; <0.004 NA --; <0.05 --; <0.05 NA --; <0.002 NA SED68 NA <0.04–<0.480 (7) <0.004–<0.005 (23) NA <0.05–<0.05 (17) <0.004–<0.05 (39) NA <0.002–<0.003 (23) NA NA --; <0.480 --; <0.004 NA --; <0.05 --; <0.018 NA --; <0.002 NA Prototype <0.1–<0.1 (9) <0.04–<0.250 (18) <0.005–<0.05 (32) <0.03–<0.03 (10) <0.03–<0.05 (21) <0.018–<0.05 (30) NA <0.003–<0.003 (32) <0.03–<0.03 (10) --; <0.1 --; <0.250 --; <0.005 --; <0.03 --; <0.05 --; <0.03 NA --; <0.003 --; <0.03

Background <0.2–<0.2 (7) <0.04–<0.04 (2) <0.004–<0.005 (62) --–<0.05 (1) <0.05–<0.05 (20) <0.004–0.017 (67) NA <0.002–<0.004 (62) --–<0.05 (1)

--; <0.2 --; -- --; <0.005 --; -- --; <0.05 --; <0.018 NA --; <0.003 --; --

Shallow index wells <0.1–0.1 (10) <0.04–<0.250 (61) <0.005–<0.005 (66) <0.05–<0.05 (10) <0.05–<0.05 (39) <0.018–<0.05 (87) NA <0.003–<0.003 (66) <0.05–<0.05 (10)

--; <0.1 --; <0.250 --; <0.005 --; <0.05 --; <0.05 --; <0.018 NA --; <0.003 --; <0.05

Deep index wells <0.1–<0.1 (9) <0.04–<0.04 (29) <0.005–<0.005 (29) <0.05–0.06 (10) <0.05–<0.05 (22) <0.018–<0.05 (32) NA <0.003–<0.003 (29) <0.05–0.17 (10)

--; <0.1 --; <0.04 --; <0.005 --; <0.05 --; <0.05 --; <0.05 NA --; <0.003 --; <0.05
Appendix 12

1

Table A–6. Summary of detections of organic compounds in water samples collected as part of the Equus Beds Groundwater Recharge Project during 1995–2005.—Continued[μg/L, micrograms per liter; MCL, Maximum Contaminant Level; --, not determined; <, less than; NA, not analyzed; HAL, Health Advisory Level; ELISA, enzyme-linked immunosorbent assay; ft, feet. The first set of numbers under each heading, for example 99–3,350, indicates the range in concentration. The number in parentheses () indicates the number of samples collected. The numbers below indicate the 

average followed by the median. Asterisk * is value estimated by using a log-probability regression to predict the values of data below the reporting level.]

Data-collection site

(fig. 6)

Desulfinylfipronil, 

dissolved 

(μg/L)

Diazinon, 

dissolved 

(μg/L)

Diazinon, 

total 

(μg/L)

Dicamba, 

total 

(μg/L)

Dimethenamid, 

dissolved 

(μg/L)

Diuron, 

dissolved 

(μg/L)1

Diuron, 

dissolved 

(μg/L)

S-Ethyl dipropylthiocarbamate, 

dissolved 

(μg/L)1

Ethalfluralin, 

dissolved 

(μg/L)1

Drinking-water criteria -- 0.600 (HAL) 0.600 (HAL) 200 (HAL) -- 10 (HAL) 10 (HAL) -- --Reporting level 0.012 0.079 0.04 0.01 0.05 0.02 0.2 0.005 0.013

07143672 

(near Halstead)

<0.004–0.006 (9) <0.002–0.079 (50) <0.01–<0.01 (3) <0.01–0.09 (5) <0.05–1.94 (21) <0.02–0.26 (4) <0.05–0.38 (4) <0.002–0.061 (41) <0.004–0.007 (41)

--; <0.012 0.009*; <0.005 --; -- --; -- 0.201*; <0.05 --; -- --; -- --; <0.002 --; <0.004

07144100 

(near Sedgwick)

<0.004–0.006 (9) <0.002–0.054 (52) <0.01–0.01 (3) <0.01–0.19 (5) <0.05–7.65 (89) <0.02–0.28 (5) <0.05–<0.2 (3) <0.002–0.061 (43) <0.004–0.007 (43)

--; <0.012 0.01; 0.004 --; -- --; -- 0.642; 0.11 --; -- --; -- --; <0.002 --; <0.004

Halstead diversion well NA <0.002–<0.005 (30) --–<0.01 (1) --–<0.01 (1) <0.05–<0.05 (8) <0.02–<0.02 (6) NA <0.002–<0.002 (30) <0.004–<0.009 (30)

NA --; <0.002 --; -- --; -- --; <0.05 --; <0.02 NA --; <0.002 --; <0.004

HAL22 <0.004–<0.012 (2) <0.002–<0.005 (14) --–<0.01 (1) --–<0.01 (1) <0.05–<0.05 (7) <0.02–0.02 (2) --–<0.05 (1) <0.002–<0.002 (12) <0.004–<0.009 (12)

--; -- --; <0.002 --; -- --; -- --; <0.05 --; -- --; -- --; <0.002 --; <0.004

HAL33 <0.004–<0.012 (2) <0.002–<0.008 (32) <0.01–<0.01 (4) <0.01–<0.01 (4) <0.05–<0.05 (11) <0.02–0.05 (3) --–<0.05 (1) <0.002–0.002 (30) <0.004–<0.013 (30)

--; -- --; <0.002 --; -- --; -- --; <0.05 --; -- --; -- --; <0.002 --; <0.004

HAL44 NA <0.002–<0.005 (11) NA NA <0.05–<0.05 (3) NA NA <0.002–<0.002 (11) <0.004–<0.009 (11)

NA --; <0.002 NA NA --; -- NA NA --; <0.002 --; <0.004

HAL75 NA <0.002–<0.005 (35) NA NA <0.05–<0.05 (11) <0.02–<0.02 (11) NA <0.002–<0.002 (35) <0.004–<0.009 (35)

NA --; <0.002 NA NA --; <0.05 --; <0.02 NA --; <0.002 --; <0.004

HAL86 NA <0.002–<0.005 (35) NA NA <0.05–<0.05 (11) <0.02–<0.02 (11) NA <0.002–<0.002 (35) <0.004–<0.009 (35)

NA --; <0.002 NA NA --; <0.05 --; <0.02 NA --; <0.002 --; <0.004

Sedgwick treated 

stream water

NA <0.002–<0.005 (13) NA NA <0.05–<0.05 (6) <0.02–<0.02 (4) NA <0.002–<0.002 (13) <0.004–<0.009 (13)

NA --; <0.002 NA NA --; <0.05 --; -- NA --; <0.002 --; <0.004

SED57 NA <0.002–<0.005 (26) NA NA <0.05–<0.05 (10) <0.02–<0.02 (6) NA <0.002–0.014 (26) <0.004–<0.009 (26)

NA --; <0.002 NA NA --; <0.05 --; <0.02 NA --; <0.002 --; <0.004

SED68 NA <0.002–<0.005 (23) NA NA <0.05–<0.05 (5) <0.02–<0.02 (7) NA <0.002–<0.002 (23) <0.004–<0.009 (23)

NA --; <0.002 NA NA --; -- --; <0.02 NA --; <0.002 --; <0.004

Prototype <0.004–<0.012 (32) <0.005–<0.005 (32) NA NA <0.05–<0.05 (11) <0.01–<0.12 (18) <0.2–<0.2 (10) <0.002–<0.002 (9) <0.009–<0.009 (9)

--; <0.012 --; <0.005 NA NA --; <0.05 --; <0.12 --; <0.2 --; <0.002 --; <0.009

Background <0.004–<0.012 (15) <0.002–<0.008 (62) <0.01–<0.01 (12) <0.01–<0.01 (12) <0.05–<0.05 (15) <0.02–<0.02 (2) --–<0.05 (1) <0.002–<0.005 (47) <0.004–<0.013 (47)

--; <0.004 --; <0.005 --; <0.01 --; <0.01 --; <0.05 --; -- --; -- --; <0.002 --; <0.004

Shallow index wells <0.004–0.007 (28) <0.005–<0.005 (66) <0.02–<0.04 (58) NA <0.05–<0.05 (29) <0.01–0.03 (61) <0.05–0.12 (10) <0.002–<0.002 (48) <0.009–<0.009 (48)

--; <0.012 --; <0.005 --; <0.02 NA --; <0.05 --; <0.12 --; <0.05 --; <0.002 --; <0.009

Deep index wells <0.004–<0.012 (29) <0.005–<0.008 (29) <0.02–<0.02 (20) NA <0.05–<0.05 (12) <0.01–<0.01 (29) <0.05–0.05 (10) <0.002–<0.002 (10) <0.009–<0.009 (10)

--; <0.012 --; <0.005 --; <0.02 NA --; <0.05 --; <0.01 --; <0.05 --; <0.002 --; <0.009
122 Water Quality in the Equus Beds Aquifer and the Little Arkansas River, South-Central Kansas Table A–6. Summary of detections of organic compounds in water samples collected as part of the Equus Beds Groundwater Recharge Project during 1995–2005.—Continued [μg/L, micrograms per liter; MCL, Maximum Contaminant Level; --, not determined; <, less than; NA, not analyzed; HAL, Health Advisory Level; ELISA, enzyme-linked immunosorbent assay; ft, feet. The first set of numbers under each heading, for example 99–3,350, indicates the range in concentration. The number in parentheses () indicates the number of samples collected. The numbers below indicate the average followed by the median. Asterisk * is value estimated by using a log-probability regression to predict the values of data below the reporting level.] Data-collection site (fig. 6) Fipronil sulfide, dissolved (μg/L) Fipronil, dissolved (μg/L) Flumetsulam, dissolved (μg/L) Glyphosate, dissolved (μg/L)1 Hexazinone, dissolved (μg/L) Imazaquin, dissolved (μg/L) Lindane, dissolved (μg/L) Linuron, dissolved (μg/L)1 Malaoxon, dissolved (μg/L) Drinking-water criteria -- -- -- -- 200 (HAL) -- 0.2 (MCL) -- -- Reporting level 0.013 0.016 0.04 0.1 0.013 0.04 0.02 0.175 0.03 07143672 (near Halstead) <0.005–0.002 (9) <0.007–0.006 (9) NA <0.1–0.8 (5) <0.013–<0.013 (7) NA <0.004–<0.02 (40) <0.002–<0.175 (41) <0.008–0.049 (9) --; <0.013 --; <0.016 NA --; -- --; <0.013 NA --; <0.004 --; <0.002 --; <0.008 07144100 (near Sedgwick) <0.005–<0.013 (9) <0.007–0.012 (9) NA <0.1–1 (5) <0.013–<0.013 (7) NA <0.004–0.009 (42) <0.002–0.008 (43) <0.008–<0.03 (9) --; <0.013 --; <0.016 NA --; -- --; <0.013 NA --; <0.004 --; <0.002 --; <0.008 Halstead diversion well NA NA NA NA NA NA <0.004–0.018 (30) <0.002–<0.035 (30) NA NA NA NA NA NA NA --; <0.004 --; <0.002 NA HAL22 <0.005–<0.013 (2) <0.007–<0.016 (2) NA --–<0.1 (1) <0.013–<0.013 (2) NA <0.004–<0.004 (12) <0.002–<0.035 (12) <0.008–<0.03 (2) --; -- --; -- NA --; -- --; -- NA --; <0.004 --; <0.002 --; -- HAL33 <0.005–<0.013 (2) <0.007–<0.016 (2) NA --–<0.1 (1) <0.013–<0.013 (2) NA <0.004–<0.011 (30) <0.002–<0.039 (30) <0.008–<0.03 (2) --; -- --; -- NA --; -- --; -- NA --; <0.004 --; <0.002 --; -- HAL44 NA NA NA NA NA NA <0.004–<0.004 (11) <0.002–<0.035 (11) NA NA NA NA NA NA NA --; <0.004 --; <0.002 NA HAL75 NA NA NA NA NA NA <0.004–<0.004 (35) <0.002–<0.035 (35) NA NA NA NA NA NA NA --; <0.004 --; <0.002 NA HAL86 NA NA NA NA NA NA <0.004–<0.004 (35) <0.002–<0.035 (35) NA NA NA NA NA NA NA --; <0.004 --; <0.002 NA Sedgwick treated stream water NA NA NA NA NA NA <0.004–<0.004 (13) <0.002–<0.035 (13) NA NA NA NA NA NA NA --; <0.004 --; <0.002 NA SED57 NA NA NA NA NA NA <0.004–<0.004 (26) <0.002–<0.035 (26) NA NA NA NA NA NA NA --; <0.004 --; <0.002 NA SED68 NA NA NA NA NA NA <0.004–<0.004 (23) <0.002–<0.035 (23) NA NA NA NA NA NA NA --; <0.004 --; <0.002 NA Prototype <0.005–<0.013 (32) <0.007–<0.016 (32) <0.04–<0.04 (8) <0.1–<0.1 (10) <0.013–<0.013 (22) <0.04–<0.04 (8) <0.004–<0.004 (9) <0.035–<0.035 (9) <0.008–<0.03 (23) --; <0.013 --; <0.016 --; <0.04 --; <0.1 --; <0.013 --; <0.04 --; <0.004 --; <0.035 --; <0.03 Background <0.005–<0.013 (15) <0.007–<0.016 (15) NA <0.1–<0.1 (7) <0.013–<0.013 (15) NA <0.004–<0.011 (47) <0.002–<0.039 (47) <0.008–<0.03 (15)

--; <0.005 --; <0.007 NA --; <0.1 --; <0.013 NA --; <0.004 --; <0.002 --; <0.008

Shallow index wells <0.005–0.005 (28) <0.007–<0.016 (28) <0.01–0.01 (30) <0.1–<0.1 (10) <0.013–0.02 (18) <0.02–0.04 (30) <0.004–<0.004 (48) <0.035–<0.035 (48) <0.008–<0.03 (18)

--; <0.013 --; <0.016 --; <0.01 --; <0.1 --; <0.013 0.012*; <0.02 --; <0.004 --; <0.035 --; <0.03

Deep index wells <0.005–<0.013 (29) <0.007–<0.016 (29) <0.01–<0.04 (29) <0.1–<0.1 (10) <0.013–<0.013 (19) <0.02–0.01 (29) <0.004–<0.004 (10) <0.035–<0.035 (10) <0.008–<0.03 (19)

--; <0.013 --; <0.016 --; <0.01 --; <0.1 --; <0.013 --; <0.02 --; <0.004 --; <0.035 --; <0.03
Appendix 12

3

Table A–6. Summary of detections of organic compounds in water samples collected as part of the Equus Beds Groundwater Recharge Project during 1995–2005.—Continued[μg/L, micrograms per liter; MCL, Maximum Contaminant Level; --, not determined; <, less than; NA, not analyzed; HAL, Health Advisory Level; ELISA, enzyme-linked immunosorbent assay; ft, feet. The first set of numbers under each heading, for example 99–3,350, indicates the range in concentration. The number in parentheses () indicates the number of samples collected. The numbers below indicate the 

average followed by the median. Asterisk * is value estimated by using a log-probability regression to predict the values of data below the reporting level.]

Data-collection site

(fig. 6)

Malathion, 

dissolved 

(μg/L)

Methyl parathion, 

dissolved 

(μg/L)1

Metolachlor 

ethanesulfonic acid, 

dissolved 

(μg/L)1

Metolachlor 

oxanilic acid, 

dissolved 

(μg/L)1

Metolachlor, 

dissolved 

(μg/L)

Metolachlor, 

total 

(μg/L)

Metribuzin, 

dissolved 

(μg/L)

Metsulfuron, 

dissolved 

(μg/L)

Molinate, 

dissolved 

(μg/L)1

Drinking-water criteria -- 2 (HAL) -- -- 70 (HAL) 70 (HAL) 100 (HAL) -- --

Reporting level 0.027 0.015 0.1 0.1 0.05 0.2 0.05 0.03 0.008

07143672 

(near Halstead)

<0.005–0.132 (50) <0.006–0.011 (50) 0.3–0.8 (6) 0.3–1.1 (6) 0.002–44.9 (140) <0.2–0.4 (3) <0.004–0.871 (140) NA <0.002–<0.008 (41)

0.006*; <0.014 --; <0.006 0.583; 0.65 0.733; 0.75 3.275; 1.105 --; -- 0.046*; <0.05 NA --; <0.004

07144100 

(near Sedgwick)

<0.005–0.214 (52) <0.006–<0.035 (52) 0.4–0.8 (5) 0.5–1.1 (5) 0.009–21.9 (350) 0.5–0.6 (2) <0.004–0.58 (350) NA <0.002–<0.008 (43)

0.006; <0.014 --; <0.006 --; -- --; -- 2.746; 1.41 --; -- 0.036; <0.05 NA --; <0.004

Halstead diversion well <0.005–<0.027 (30) <0.006–<0.006 (30) --–0.1 (1) --–0.1 (1) <0.002–0.025 (100) --–<0.2 (1) <0.004–<0.05 (100) NA <0.002–0.001 (30)

--; <0.005 --; <0.006 --; -- --; -- 0.014*; <0.05 --; -- --; <0.05 NA --; <0.004

HAL22 <0.005–<0.027 (14) <0.006–<0.015 (14) --–0.1 (1) --–0.2 (1) <0.002–0.045 (33) NA <0.004–<0.05 (33) NA <0.002–<0.004 (12)

--; <0.005 --; <0.006 --; -- --; -- 0.014*; <0.05 NA --; <0.05 NA --; <0.004

HAL33 <0.005–<0.027 (32) <0.006–<0.035 (32) --–0.5 (1) --–0.5 (1) <0.002–1 (94) NA <0.004–0.021 (94) NA <0.002–<0.007 (30)

--; <0.005 --; <0.006 --; -- --; -- 0.079*; 0.012 NA --; <0.05 NA --; <0.004

HAL44 <0.005–<0.027 (11) <0.006–<0.006 (11) NA NA <0.002–<0.05 (29) NA <0.004–<0.05 (29) NA <0.002–<0.004 (11)

--; <0.005 --; <0.006 NA NA --; <0.05 NA --; <0.05 NA --; <0.004

HAL75 <0.005–<0.027 (35) <0.006–<0.006 (35) <0.1–0.1 (2) <0.1–<0.1 (2) <0.002–0.02 (65) NA <0.004–<0.05 (65) NA <0.002–<0.004 (35)

--; <0.005 --; <0.006 --; -- --; -- 0.008*; <0.05 NA --; <0.004 NA --; <0.004

HAL86 <0.005–<0.027 (35) <0.006–<0.006 (35) 0.1–0.1 (2) 0.1–0.1 (2) <0.002–0.023 (71) NA <0.004–<0.05 (71) NA <0.002–<0.004 (35)

--; <0.005 --; <0.006 --; -- --; -- 0.016*; <0.05 NA --; <0.05 NA --; <0.004

Sedgwick treated 

stream water

<0.005–<0.027 (13) <0.006–<0.006 (13) --–0.6 (1) --–0.8 (1) <0.05–3.82 (65) NA <0.004–0.06 (65) NA <0.002–<0.004 (13)

--; <0.005 --; <0.006 --; -- --; -- 0.326*; 0.11 NA 0.011*; <0.05 NA --; <0.004

SED57 <0.005–<0.027 (26) <0.006–<0.006 (26) 0.1–0.6 (3) <0.1–0.1 (3) <0.05–7.01 (70) NA <0.004–0.007 (70) NA <0.002–<0.004 (26)

--; <0.005 --; <0.006 --; -- --; -- 0.949*; 0.133 NA --; <0.05 NA --; <0.004

SED68 <0.005–<0.027 (23) <0.006–<0.006 (23) <0.1–<0.1 (2) <0.1–<0.1 (2) <0.002–0.01 (39) NA <0.004–<0.05 (39) NA <0.002–<0.004 (23)

--; <0.005 --; <0.006 --; -- --; -- --; <0.05 NA --; <0.006 NA --; <0.004

Prototype <0.027–<0.027 (32) <0.006–<0.015 (32) <0.1–<0.1 (10) <0.1–<0.1 (10) <0.006–0.003 (43) NA <0.006–<0.05 (43) <0.03–<0.03 (8) <0.002–<0.002 (9)

--; <0.027 --; <0.015 --; <0.1 --; <0.1 --; <0.013 NA --; <0.006 --; <0.03 --; <0.002

Background <0.005–<0.027 (62) <0.006–<0.035 (62) <0.1–0.2 (7) <0.1–0.1 (7) <0.002–0.77 (81) NA <0.004–0.01 (81) NA <0.002–<0.007 (47)

--; <0.014 --; <0.006 --; 0.1 --; <0.1 0.020*; <0.013 NA --; <0.006 NA --; <0.004

Shallow index wells <0.027–<0.027 (66) <0.006–<0.015 (66) <0.1–3.8 (10) <0.1–0.7 (10) <0.006–2.61 (95) NA <0.006–<0.05 (95) <0.03–0.02 (29) <0.002–0.005 (48)

--; <0.027 --; <0.006 0.764*; 0.2 --; <0.1 0.093*; <0.013 NA --; <0.006 --; <0.03 --; <0.002

Deep index wells <0.027–<0.027 (29) <0.006–<0.015 (29) <0.1–<0.1 (10) <0.1–<0.1 (10) <0.006–0.015 (41) NA <0.006–<0.05 (41) <0.03–<0.03 (28) <0.002–<0.002 (10)

--; <0.027 --; <0.015 --; <0.1 --; <0.1 --; <0.013 NA --; <0.006 --; <0.03 --; <0.002
124 Water Quality in the Equus Beds Aquifer and the Little Arkansas River, South-Central Kansas Table A–6. Summary of detections of organic compounds in water samples collected as part of the Equus Beds Groundwater Recharge Project during 1995–2005.—Continued [μg/L, micrograms per liter; MCL, Maximum Contaminant Level; --, not determined; <, less than; NA, not analyzed; HAL, Health Advisory Level; ELISA, enzyme-linked immunosorbent assay; ft, feet. The first set of numbers under each heading, for example 99–3,350, indicates the range in concentration. The number in parentheses () indicates the number of samples collected. The numbers below indicate the average followed by the median. Asterisk * is value estimated by using a log-probability regression to predict the values of data below the reporting level.] Data-collection site (fig. 6) Napropamide, dissolved (μg/L)1 Nicosulfuron, dissolved (μg/L) p,p'-dichlorodiphe- nyldichloro-ethylene, dissolved (μg/L) Pendimethalin, dissolved (μg/L)1 Picloram, total (μg/L) Prometon, dissolved (μg/L) Prometryn, dissolved (μg/L) Propyzamide, dissolved (μg/L)1 Propachlor, dissolved (μg/L) Drinking-water criteria -- -- -- -- 500 (MCL) 100 (HAL) -- 50 (HAL) 90 (HAL) Reporting level 0.035 0.04 0.013 0.075 0.01 0.05 0.05 0.021 0.05 07143672 (near Halstead) <0.003–<0.035 (41) NA <0.003–0.002 (41) <0.004–0.89 (72) <0.01–0.06 (5) <0.01–0.32 (140) <0.005–0.12 (99) <0.003–0.007 (50) <0.007–0.2 (131) --; <0.003 NA --; <0.006 --; <0.022 --; -- 0.030*; <0.05 --; <0.05 --; <0.003 0.010*; <0.05 07144100 (near Sedgwick) <0.003–<0.035 (43) NA <0.003–<0.013 (43) <0.004–0.015 (141) <0.01–0.09 (5) <0.01–0.8 (350) <0.005–0.2 (307) <0.003–<0.021 (52) <0.007–1.13 (335) --; <0.003 NA --; <0.006 --; <0.05 --; -- 0.032; <0.05 --; <0.05 --; <0.003 --; <0.05 Halstead diversion well <0.003–<0.007 (30) NA <0.003–0.001 (30) <0.004–<0.05 (38) --–<0.01 (1) <0.01–0.02 (100) <0.05–<0.05 (70) <0.003–<0.004 (30) <0.007–<0.05 (100) --; <0.003 NA --; <0.006 --; <0.004 --; -- --; <0.05 --; <0.05 --; <0.003 --; <0.05 HAL22 <0.003–<0.007 (12) NA <0.003–<0.006 (12) <0.004–<0.05 (21) --–<0.01 (1) <0.01–0.01 (33) <0.005–0.006 (21) <0.003–<0.004 (14) <0.007–<0.05 (31) --; <0.003 NA --; <0.006 --; <0.01 --; -- 0.010*; <0.05 --; <0.05 --; <0.003 --; <0.05 HAL33 <0.003–<0.01 (30) NA <0.003–<0.01 (30) <0.004–<0.05 (43) <0.01–<0.01 (4) <0.01–0.02 (94) <0.005–<0.05 (65) <0.003–<0.009 (32) <0.007–<0.05 (92) --; <0.003 NA --; <0.006 --; <0.004 --; -- 0.009*; <0.05 --; <0.05 --; <0.003 --; <0.05 HAL44 <0.003–<0.007 (11) NA <0.003–0.002 (11) <0.004–<0.05 (14) NA <0.01–<0.05 (29) <0.05–<0.05 (18) <0.003–<0.004 (11) <0.007–<0.05 (29) --; <0.003 NA --; <0.006 --; <0.004 NA --; <0.05 --; <0.05 --; <0.003 --; <0.05 HAL75 <0.003–<0.016 (35) NA <0.003–<0.006 (35) <0.004–<0.05 (46) NA <0.02–0.01 (65) <0.05–0.29 (30) <0.003–<0.004 (35) <0.007–<0.05 (65) --; <0.003 NA --; <0.006 --; <0.004 NA 0.010*; <0.05 --; <0.05 --; <0.003 --; <0.007 HAL86 <0.003–0.004 (35) NA <0.003–0.002 (35) <0.004–<0.05 (46) NA <0.01–0.05 (71) <0.05–<0.05 (36) <0.003–<0.004 (35) <0.007–<0.05 (71) --; <0.003 NA --; <0.006 --; <0.004 NA --; <0.05 --; <0.05 --; <0.003 --; <0.05 Sedgwick treated stream water <0.003–<0.007 (13) NA <0.003–<0.006 (13) <0.004–<0.05 (20) NA <0.02–0.06 (65) <0.05–<0.05 (52) <0.003–<0.004 (13) <0.007–<0.05 (65) --; <0.003 NA --; <0.006 --; <0.004 NA 0.014*; <0.05 --; <0.05 --; <0.003 --; <0.05 SED57 <0.003–<0.007 (26) NA <0.003–0.001 (26) <0.004–<0.05 (37) NA <0.01–0.01 (70) <0.05–<0.05 (44) <0.003–<0.004 (26) <0.007–<0.05 (70) --; <0.003 NA --; <0.006 --; <0.004 NA --; <0.05 --; <0.05 --; <0.003 --; <0.05 SED68 <0.003–<0.007 (23) NA <0.003–0.001 (23) <0.004–<0.05 (28) NA <0.01–<0.05 (39) <0.05–<0.05 (17) <0.003–<0.004 (23) <0.007–<0.05 (39)

--; <0.003 NA --; <0.006 --; <0.004 NA --; <0.02 --; <0.05 --; <0.003 --; <0.01

Prototype <0.007–<0.009 (9) <0.04–<0.04 (8) <0.003–<0.003 (9) <0.022–<0.075 (43) NA <0.01–<0.05 (43) <0.005–<0.05 (34) <0.004–<0.004 (32) <0.01–<0.05 (20)

--; <0.007 --; <0.04 --; <0.003 --; <0.022 NA --; <0.01 --; <0.005 --; <0.004 --; <0.05

Background <0.003–<0.01 (47) NA <0.003–0.001 (47) <0.004–<0.05 (77) <0.01–<0.01 (12) <0.01–0.01 (81) <0.005–<0.05 (34) <0.003–<0.009 (62) <0.007–<0.05 

(66)

--; <0.003 NA --; <0.006 --; <0.018 --; <0.01 --; <0.02 --; <0.05 --; <0.004 --; <0.01

Shallow index wells <0.007–<0.007 (48) <0.01–0.03 (30) <0.003–<0.003 (48) <0.022–<0.05 (95) NA <0.01–0.14 (95) <0.005–0.012 (47) <0.004–<0.004 (66) <0.01–<0.05 (77)

--; <0.007 --; <0.01 --; <0.003 --; <0.022 NA 0.010*; <0.01 --; <0.05 --; <0.004 --; <0.01

Deep index wells <0.007–<0.007 (10) <0.01–<0.04 (29) <0.003–<0.003 (10) <0.022–<0.05 (41) NA <0.01–<0.05 (41) <0.005–<0.05 (31) <0.004–<0.004 (29) <0.01–<0.05 (22)

--; <0.007 --; <0.01 --; <0.003 --; <0.022 NA --; <0.01 --; <0.005 --; <0.004 --; <0.05
Appendix 12

5

Table A–6. Summary of detections of organic compounds in water samples collected as part of the Equus Beds Groundwater Recharge Project during 1995–2005.—Continued[μg/L, micrograms per liter; MCL, Maximum Contaminant Level; --, not determined; <, less than; NA, not analyzed; HAL, Health Advisory Level; ELISA, enzyme-linked immunosorbent assay; ft, feet. The first set of numbers under each heading, for example 99–3,350, indicates the range in concentration. The number in parentheses () indicates the number of samples collected. The numbers below indicate the 

average followed by the median. Asterisk * is value estimated by using a log-probability regression to predict the values of data below the reporting level.]

Data-collection site

(fig. 6)

Propazine, 

dissolved 

(μg/L)

Propazine, 

total 

(μg/L)

Roxithromycin, 

dissolved 

(μg/L)

Simazine, 

dissolved 

(μg/L)

Simazine, 

total 

(μg/L)

Tebuthiuron, 

dissolved 

(μg/L)1

Terbacil, 

dissolved 

(μg/L)1

Terbuthylazine, 

dissolved 

(μg/L)

Trifluralin, 

dissolved 

(μg/L)1

Drinking-water criteria 10 (HAL) 10 (HAL) -- 4.0 (MCL) 4.0 (MCL) 500 (HAL) 90 (HAL) -- 5.0 (HAL)

Reporting level 0.05 0.1 0.1 0.05 0.1 0.02 0.17 0.01 0.012

07143672 

(near Halstead)

<0.03–2.46 (94) <0.1–0.1 (3) NA <0.005–0.11 (144) <0.1–0.2 (3) <0.01–0.24 (50) <0.007–0.009 (41) <0.01–0.1 (12) <0.002–0.028 (50)

0.087*; <0.05 --; -- NA 0.020*; <0.05 --; -- 0.023*; <0.02 --; <0.007 --; <0.01 0.006*; <0.012

07144100 

(near Sedgwick)

<0.03–5.22 (301) <0.1–0.1 (2) NA <0.005–1.67 (353) 0.2–0.2 (2) <0.01–0.2 (52) <0.007–<0.170 (43) <0.01–0.2 (14) <0.002–0.045 (52)

0.082; <0.05 --; -- NA 0.027; <0.05 --; -- 0.026; 0.01 --; <0.007 --; <0.01 0.006; <0.012

Halstead diversion well <0.05–<0.05 (70) --–<0.1 (1) NA <0.005–0.015 (100) --–<0.1 (1) <0.01–0.02 (30) <0.007–<0.034 (30) NA <0.002–<0.009 (30)

--; <0.05 --; -- NA --; <0.05 --; -- 0.008*; <0.01 --; <0.007 NA --; <0.002

HAL22 <0.05–<0.05 (20) NA NA <0.005–<0.05 (34) NA <0.01–0.01 (14) <0.007–<0.034 (12) <0.01–<0.01 (2) <0.002–<0.009 (14)

--; <0.05 NA NA --; <0.05 NA 0.010*; <0.02 --; <0.007 --; -- --; <0.002

HAL33 <0.05–<0.05 (64) NA NA <0.005–<0.05 (95) NA <0.01–0.05 (32) <0.007–<0.034 (30) <0.01–<0.01 (3) <0.002–<0.012 (32)

--; <0.05 NA NA --; <0.05 NA 0.014*; 0.01 --; <0.007 --; -- --; <0.002

HAL44 <0.05–<0.05 (18) NA NA <0.005–<0.05 (29) NA <0.01–<0.02 (11) <0.007–<0.034 (11) NA <0.002–<0.009 (11)

--; <0.05 NA NA --; <0.05 NA --; <0.01 --; <0.007 NA --; <0.002

HAL75 <0.05–<0.05 (30) NA NA <0.005–0.003 (65) NA <0.01–<0.02 (35) <0.007–<0.034 (35) NA <0.002–0.004 (35)

--; <0.05 NA NA --; <0.011 NA --; <0.01 --; <0.007 NA --; <0.002

HAL86 <0.05–<0.5 (36) NA NA <0.005–<0.05 (71) NA <0.01–0.01 (35) <0.007–<0.034 (35) NA <0.002–<0.009 (35)

--; <0.05 NA NA --; <0.05 NA --; <0.01 --; <0.007 NA --; <0.002

Sedgwick treated 

stream water

<0.05–0.07 (52) NA NA <0.005–0.033 (65) NA <0.01–0.02 (13) <0.007–<0.034 (13) --–0 (1) <0.002–0.004 (13)

--; <0.05 NA NA --; <0.05 NA --; <0.01 --; <0.007 --; -- --; <0.002

SED57 <0.05–0.07 (44) NA NA <0.005–0.006 (70) NA <0.01–<0.02 (26) <0.007–<0.034 (26) --–0.1 (1) <0.002–0.001 (26)

0.036*; <0.05 NA NA --; <0.05 NA --; <0.01 --; <0.007 --; -- --; <0.002

SED68 <0.05–<0.05 (17) NA NA <0.005–<0.05 (39) NA <0.01–<0.02 (23) <0.007–<0.034 (23) NA <0.002–<0.009 (23)

--; <0.05 NA NA --; <0.011 NA --; <0.01 --; <0.007 NA --; <0.002

Prototype <0.03–<0.05 (21) NA <0.1–<0.1 (9) <0.005–<0.05 (53) NA <0.02–<0.02 (32) <0.034–<0.034 (9) <0.01–<0.01 (23) <0.009–<0.009 (32)

--; <0.05 NA --; <0.1 --; <0.005 NA --; <0.02 --; <0.034 --; <0.01 --; <0.009

Background <0.05–<0.05 (20) NA NA <0.005–0.007 (82) NA <0.01–0.01 (62) <0.007–<0.034 (47) <0.01–<0.01 (15) <0.002–<0.012 (62)

--; <0.05 NA NA --; <0.005 NA --; <0.01 --; <0.007 --; <0.01 --; <0.009

Shallow index wells <0.05–<0.05 (39) NA <0.1–<0.1 (10) <0.005–0.007 (105) NA <0.02–0.02 (67) <0.034–<0.034 (48) <0.01–<0.01 (18) <0.009–<0.009 (66)

--; <0.05 NA --; <0.1 --; <0.005 NA --; <0.02 --; <0.034 --; <0.01 --; <0.009

Deep index wells <0.05–<0.05 (22) NA <0.1–0.1 (9) <0.005–<0.05 (51) NA <0.02–<0.02 (29) <0.034–<0.034 (10) <0.01–<0.01 (19) <0.009–<0.009 (29)

--; <0.05 NA --; <0.1 --; <0.005 NA --; <0.02 --; <0.034 --; <0.01 --; <0.009
126 Water Quality in the Equus Beds Aquifer and the Little Arkansas River, South-Central Kansas Table A–6. Summary of detections of organic compounds in water samples collected as part of the Equus Beds Groundwater Recharge Project during 1995–2005.—Continued [μg/L, micrograms per liter; MCL, Maximum Contaminant Level; --, not determined; <, less than; NA, not analyzed; HAL, Health Advisory Level; ELISA, enzyme-linked immunosorbent assay; ft, feet. The first set of numbers under each heading, for example 99–3,350, indicates the range in concentration. The number in parentheses () indicates the number of samples collected. The numbers below indicate the average followed by the median. Asterisk * is value estimated by using a log-probability regression to predict the values of data below the reporting level.] Data-collection site (fig. 6) 1,2-Dichloroethane, total, (μg/L) Bromodichloromethane, total, (μg/L) Dibromochloromethane, total (μg/L) Methyl tert-butyl ether, total (μg/L) Tetrachloroethene, total, (μg/L) Trichloromethane, total, (μg/L) Drinking-water criteria 5 (MCL) -- 100 (MCL) -- 5 (MCL) 100 (MCL) Reporting level 3.0 3.0 3.0 3.0 3.0 3.0 07143672 (near Halstead) <0.2–<3 (9) <0.2–<3 (9) <0.2–<3 (9) <0.2–<3 (9) <0.2–<3 (9) <0.2–<3 (9) --; <0.2 --; <0.2 --; <0.2 --; <0.2 --; <0.2 --; <0.2 07144100 (near Sedgwick) <0.2–<3 (7) <0.2–<3 (7) <0.2–<3 (7) <0.2–<3 (7) <0.2–<3 (7) <0.2–<3 (7) --; <3 --; <3 --; <3 --; <3 --; <3 --; <3 Halstead diversion well <0.2–<0.2 (13) <0.2–<0.2 (12) <0.2–<0.2 (13) <0.2–<0.2 (13) <0.2–<0.2 (13) <0.2–<0.2 (13) --; <0.2 --; <0.2 --; <0.2 --; <0.2 --; <0.2 --; <0.2 HAL22 <0.2–<0.2 (4) <0.2–<0.2 (4) <0.2–<0.2 (4) <0.2–<0.2 (4) <0.2–<0.2 (4) <0.2–<0.2 (4) --; -- --; -- --; -- --; -- --; -- --; -- HAL33 <0.2–<3 (10) <0.2–<3 (10) <0.2–<3 (10) <0.2–<3 (10) <0.2–<3 (10) <0.2–<3 (10) --; <0.2 --; <0.2 --; <0.2 --; <0.2 --; <0.2 --; <0.2 HAL44 <0.2–<0.2 (2) <0.2–<0.2 (2) <0.2–<0.2 (2) <0.2–<0.2 (2) <0.2–<0.2 (2) <0.2–<0.2 (2) --; -- --; -- --; -- --; -- --; -- --; -- HAL75 <0.2–<0.2 (21) <0.2–0.3 (21) <0.2–0.3 (21) <0.2–<0.2 (21) <0.2–0.9 (21) <0.2–0.5 (21) --; <0.2 --; <0.2 --; <0.2 --; <0.2 --; <0.2 --; <0.2 HAL86 <0.2–<0.2 (21) <0.2–<0.2 (21) <0.2–<0.2 (21) <0.2–<0.2 (21) <0.2–<0.2 (21) <0.2–0.3 (21) --; <0.2 --; <0.2 --; <0.2 --; <0.2 --; <0.2 --; <0.2 Sedgwick treated stream water <0.2–<0.2 (4) <0.2–<0.2 (4) <0.2–<0.2 (4) <0.2–<0.2 (4) <0.2–<0.2 (4) <0.2–<0.2 (4) --; -- --; -- --; -- --; -- --; -- --; -- SED57 <0.2–<0.4 (8) <0.2–<0.4 (8) <0.2–<0.4 (8) <0.2–<0.4 (8) <0.2–<0.4 (8) <0.2–<0.4 (8) --; <0.2 --; <0.2 --; <0.2 --; <0.2 --; <0.2 --; <0.2 SED68 <0.2–<0.2 (7) <0.2–<0.2 (7) <0.2–<0.2 (7) <0.2–<0.2 (7) <0.2–<0.2 (7) <0.2–<0.2 (7) --; <0.2 --; <0.2 --; <0.2 --; <0.2 --; <0.2 --; <0.2 Prototype <0.2–<0.2 (8) <0.1–<0.1 (8) <0.2–<0.2 (8) <0.2–<0.2 (8) <0.1–<0.1 (8) <0.1–<0.1 (8) --; <0.2 --; <0.1 --; <0.2 --; <0.2 --; <0.1 --; <0.1 Background <0.2–<3 (14) <0.2–<3 (14) <0.2–<3 (14) <0.2–<3 (14) <0.2–<3 (14) <0.2–<3 (14) --; <3 --; <3 --; <3 --; <3 --; <3 --; <3

Shallow index wells <0.2–0.8 (67) <0.1–<0.2 (67) <0.2–<0.2 (67) <0.2–0.2 (67) <0.1–<0.2 (67) <0.1–1 (67)

--; <0.2 --; <0.2 --; <0.2 --; <0.2 --; <0.2 --; <0.2

Deep index wells <0.2–1.7 (39) <0.1–<0.2 (39) <0.2–<0.2 (39) <0.2–5.8 (39) <0.1–<0.2 (39) <0.1–0.2 (39)

--; <0.2 --; <0.2 --; <0.2 --; <0.2 --; <0.2 --; <0.2

1 Constituent was analyzed using a 0.7-micron glass fiber filter.2 Deep monitoring well at diversion well site near Halstead, Kansas.3 Shallow monitoring wells within 500 feet of Little Arkansas River at diversion well site near Halstead, Kansas.4 Shallow monitoring wells more than 500 feet from Little Arkansas River at diversion well site near Halstead, Kansas.5 Shallow monitoring wells at Halstead recharge site near Halstead, Kansas.6 Deep monitoring wells at Halstead recharge site near Halstead, Kansas.7 Shallow monitoring wells at Sedgwick recharge site near Sedgwick, Kansas.8 Deep monitoring wells at Sedgwick recharge site near Sedgwick, Kansas.
Appendix 12

7

Table A–7. Summary of bacteria and viral indicator detections and triazine herbicide concentrations in water samples collected as part of the Equus Beds Groundwater 

Recharge Project during 1995–2005.

[cfu/100 mL, colony forming units per 100 milliliters; pfu/100 mL, plaque forming units per 100 milliliters; m-TEC, membrane-thermotolerant Escherichia coli; MF, membrane filter; col/100 mL, colonies per 100 milliliters; μg/L, micrograms per liter; ELISA, enzyme-linked immunosorbent assay; --, not determined; MCLG, Maximum Contaminant Level Goal; MCL, Maximum Contaminant Level; <, less than; NA, not analyzed. The first set of numbers under each heading, for example 99–3,350, indicates the range in concentration. The number in parentheses () indicates the number of samples collected. The numbers below indicate the average followed by the median. Asterisk * is value estimated by using a log-probability regression to predict the values of data below the detection level.]

Data-collection site

(fig. 6)

Clostridium perfringens 

(cfu/100 mL)

Coliphage, Escherichia 

coli, C13 host 

(pfu/100 mL)

Coliphage, Escherichia 

coli, Famp host 

(pfu/100 mL)

Enterococci

(cfu/100 mL)

Escherichia coli, modified 

m-TEC MF method

(cfu/100 mL)

Escherichia coli, m-TEC 

MF method

(cfu/100 mL)

Fecal coliform

(col/100 mL)

Fecal streptococci

(cfu/100 mL)

Drinking-water criteria -- -- -- -- -- -- -- --

Reporting level 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0

Surface-water monitoring sites (Little Arkansas River)

7143672 

(near Halstead)

150–270 (4) 600–1,200 (5) <1–73 (5) 34–26,500 (25) 20–12,000 (47) 36–41,000 (21) 4–3,000,000 (219) -- –440 (1)

--; -- --; -- --; -- 4,330; 690 1,870; 820 3,420; 425 17,200; 560 --; --

7144100 

(near Sedgwick)

120–360 (3) 40–1,300 (4) <1–290 (4) 27–198,000 (48) 4–38,000 (49) 21–23,000 (45) 1–4,000,000 (239) 2,570–7,400 (2)

--; -- --; -- --; -- 10,000; 635 5,290; 1,700 1,610; 144 21,600; 680 --; --

Diversion well site near Halstead

Diversion well NA NA NA NA NA NA <1–36 (111) NA

NA NA NA NA NA NA --; <1 NA

EB-145-A1 NA <1–<1 (2) <1–<1 (2) NA NA NA <1–1 (62) NA

NA --; -- --; -- NA NA NA --; <1 NA

EB-145-A2 NA --–<1 (1) --–<1 (1) NA NA NA <1–15 (28) NA

NA --; -- --; -- NA NA NA --; <1 NA

EB-145-A3 NA --–<1 (1) --–1 (1) NA NA NA <1–17 (32) NA

NA --; -- --; -- NA NA NA --; <1 NA

EB-145-A4 NA NA NA NA NA NA <1–<2 (21) NA

NA NA NA NA NA NA --; <1 NA

EB-145-A5 NA <1–<1 (2) <1–<1 (2) NA NA NA <1–<4 (31) NA

NA --; -- --; -- NA NA NA --; <1 NA

EB-145-P-D5 NA <1–<1 (2) <1–<1 (2) NA NA NA <1–29 (56) NA

NA --; -- --; -- NA NA NA --; <1 NA

Halstead recharge site

SMW-H4 NA --–<1 (1) --–<1 (1) NA NA NA <1–1 (47) NA

NA --; -- --; -- NA NA NA --; <1 NA

SMW-H14 NA --–<1 (1) --–<1 (1) NA NA NA <1–21 (46) NA

NA --; -- --; -- NA NA NA --; <1 NA

DMW-H1 NA --–<1 (1) --–<1 (1) NA NA NA <1–2 (46) NA

NA --; -- --; -- NA NA NA --; <1 NA

DMW-H13 NA --–<1 (1) --–<1 (1) NA NA NA <1–7 (46) NA

NA --; -- --; -- NA NA NA --; <1 NA

Sedgwick recharge site

Treated stream water NA NA NA NA NA 96–650 (2) <1–3,200 (50) NA

NA NA NA NA NA --; -- 336*; 120 NA

SMW-S11 NA --–<1 (1) --–<1 (1) NA NA NA <1–14 (52) NA

NA --; -- --; -- NA NA NA 0.437*; <1 NA

SMW-S13 NA --–<1 (1) --–<1 (1) NA NA NA <1–65 (47) NA

NA --; -- --; -- NA NA NA --; <1 NA

DMW-S10 NA --–<1 (1) --–<1 (1) NA NA NA <1–<2 (40) NA

NA --; -- --; -- NA NA NA --; <1 NA

DMW-S14 NA --–<1 (1) --–<1 (1) NA NA NA <1–17 (36) NA

NA --; -- --; -- NA NA NA --; <1 NA
128 Water Quality in the Equus Beds Aquifer and the Little Arkansas River, South-Central Kansas Table A–7. Summary of bacteria and viral indicator detections and triazine herbicide concentrations in water samples collected as part of the Equus Beds Groundwater Recharge Project during 1995–2005.—Continued [cfu/100 mL, colony forming units per 100 milliliters; pfu/100 mL, plaque forming units per 100 milliliters; m-TEC, membrane- thermotolerant Escherichia coli; MF, membrane filter; col/100 mL, colonies per 100 milliliters; μg/L, micrograms per liter; ELISA, enzyme-linked immunosorbent assay; --, not determined; MCLG, Maximum Contaminant Level Goal; MCL, Maximum Contami- nant Level; <, less than; NA, not analyzed. The first set of numbers under each heading, for example 99–3,350, indicates the range in concentration. The number in parentheses () indicates the number of samples collected. The numbers below indicate the average followed by the median. Asterisk * is value estimated by using a log-probability regression to predict the values of data below the detection level.] Data-collection site (fig. 6) Total coliform (col/100 mL) Atrazine (μg/L) Triazine screen, ELISA (μg/L as atrazine) Drinking-water criteria 0 (MCLG) 3.0 (MCL) -- Reporting level 1.0 0.05 0.1 Surface-water monitoring sites (Little Arkansas River) 7143672 (near Halstead) 1–2,000,000 (150) 0.028–46.2 (144) <0.1–50 (696) 22,000; 1,500 5.55; 3.11 2.6*; 1 7144100 (near Sedgwick) <1–9,000,000 (147) 0.04–48 (351) 0.1–40 (2469) 71,100*; 1,800 5.92; 3.47 4.0; 2 Diversion well site near Halstead Diversion well <1–21 (111) <0.05–0.101 (100) <0.1–0.4 (283) 0.628; <1 0.06; 0.07 0.06; <0.1 EB-145-A1 <1–26 (62) <0.007–2.2 (51) <0.1–3 (67) 0.851*; <1 0.289*; 0.05 0.5*; 0.2 EB-145-A2 <1–7 (28) <0.05–0.91 (22) <0.1–2 (28) --; <1 0.193*; 0.08 0.5*; 0.2 EB-145-A3 <1–14 (31) <0.001–0.13 (22) <0.1–0.2 (33) --; <1 0.046*; 0.01 0.1*; <0.1 EB-145-A4 <1–<2 (21) <0.001–0.01 (12) <0.1–<0.1 (22) --; <1 --; <0.05 --; <0.1 EB-145-A5 <1–2 (31) <0.001–<0.05 (17) <0.1–0.3 (33) --; <1 --; <0.05 --; <0.1 EB-145-P-D5 <1–56 (56) <0.001–0.18 (34) <0.1–0.3 (57) 1.72*; <1 0.063*; 0.06 0.08*; <0.1 Halstead recharge site SMW-H4 <1–10 (47) <0.05–0.142 (31) <0.1–0.4 (46) 0.448*; <1 0.046*; 0.04 0.07*; <0.1 SMW-H14 <1–99 (46) <0.05–0.52 (34) <0.1–0.5 (46) 3.13*; <1 0.070*; 0.04 0.03*; <0.1 DMW-H1 <1–2 (46) <0.05–0.1 (34) <0.1–0.2 (46) --; <1 0.053*; 0.07 0.07*; <0.1

DMW-H13 <1–80 (46) <0.001–0.09 (37) <0.1–0.2 (46)

2.47*; <1 0.060*; 0.06 0.06*; <0.1

Sedgwick recharge site

Treated stream water <1–7000 (48) <0.05–6.71 (65) <0.1–7 (228)

393*; 80 0.517*; 0.22 0.3*; <0.1

SMW-S11 <1–196 (52) <0.05–0.39 (41) <0.1–1 (52)

5.82*; <1 0.142*; 0.11 0.2*; 0.1

SMW-S13 <1–56 (47) <0.05–0.16 (29) <0.1–0.2 (47)

3.16*; <1 0.037*; 0.01 0.04*; <0.1

DMW-S10 <1–8 (40) <0.001–<0.05 (18) <0.1–<0.1 (40)

0.451*; <1 --; <0.001 --; <0.1

DMW-S14 <1–4 (36) <0.001–0.004 (20) <0.1–0.1 (36)

0.524*; <1 --; <0.05 --; <0.1
Appendix 12

9

Table A–7. Summary of bacteria and viral indicator detections and triazine herbicide concentrations in water samples collected as part of the Equus Beds Groundwater 

Recharge Project during 1995–2005.—Continued

[cfu/100 mL, colony forming units per 100 milliliters; pfu/100 mL, plaque forming units per 100 milliliters; m-TEC, membrane-thermotolerant Escherichia coli; MF, membrane filter; col/100 mL, colonies per 100 milliliters; μg/L, micrograms per liter; ELISA, enzyme-linked immunosorbent assay; --, not determined; MCLG, Maximum Contaminant Level Goal; MCL, Maximum Contaminant Level; <, less than; NA, not analyzed. The first set of numbers under each heading, for example 99–3,350, indicates the range in concentration. The number in parentheses () indicates the number of samples collected. The numbers below indicate the average followed by the median. Asterisk * is value estimated by using a log-probability regression to predict the values of data below the detection level.]

Data-collection site

(fig. 6)

Clostridium 

perfringens 

(cfu/100 mL)

Coliphage, Escherichia 

coli, C13 host 

(pfu/100 mL)

Coliphage, Escherichia 

coli, Famp host 

(pfu/100 mL)

Enterococci

(cfu/100 mL)

Escherichia coli, modified 

m-TEC MF method

(cfu/100 mL)

Escherichia coli, m-TEC 

MF method

(cfu/100 mL)

Fecal coliform

(col/100 mL)

Fecal streptococci

(cfu/100 mL)

Drinking-water criteria -- -- -- -- -- -- -- --

Reporting level 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0

Background wells

EB-142-A3 NA NA NA NA NA NA <2–<2 (3) NA

NA NA NA NA NA NA --; -- NA

Sedgwick well NA --–<1 (1) --–<1 (1) NA NA NA <1–<10 (45) NA

NA --; -- --; -- NA NA NA --; <1 NA

City well-Sedgwick NA NA NA NA NA NA --–<1 (1) NA

NA NA NA NA NA NA --; -- NA

TH-02-95 NA --–<1 (1) --–<1 (1) NA NA NA <1–6 (25) NA

NA --; -- --; -- NA NA NA --; <1 NA

TH-06-95 NA --–<1 (1) --–<1 (1) NA NA NA <1–<2 (27) NA

NA --; -- --; -- NA NA NA --; <1 NA

TH-10-95 NA --–<1 (1) --–<1 (1) NA NA NA <1–3 (26) NA

NA --; -- --; -- NA NA NA --; <1 NA

TH-12-95 NA NA NA NA NA NA --–<1 (1) NA

NA NA NA NA NA NA --; -- NA

TH-08-A1 NA NA NA NA NA NA <1–<4 (7) NA

NA NA NA NA NA NA --; <2 NA

TH-08-A2 NA NA NA NA NA NA <1–<2 (10) NA

NA NA NA NA NA NA --; <1 NA

TH-08-A3 NA --–<1 (1) --–1 (1) NA NA NA <1–<2 (23) NA

NA --; -- --; -- NA NA NA --; <1 NA

TH-08-A4 NA NA NA NA NA NA --–<1 (1) NA

NA NA NA NA NA NA --; -- NA

TH-08-A5 NA NA NA NA NA NA <1–<1 (12) NA

NA NA NA NA NA NA --; <1 NA

Alta Mills NA --–<1 (1) --–<1 (1) NA NA NA <1–<10 (23) NA

NA --; -- --; -- NA NA NA --; <1 NA

Aquifer storage and recovery prototype wells

DW-TW-01 NA --–<1 (1) --–<1 (1) NA NA NA <1–1 (7) NA

NA --; -- --; -- NA NA NA --; <1 NA

DW-TW-02 NA --–<1 (1) --–<1 (1) NA NA NA <1–<1 (7) NA

NA --; -- --; -- NA NA NA --; <1 NA

DW-TW-03 NA --–<1 (1) --–<1 (1) NA NA NA <1–<1 (7) NA

NA --; -- --; -- NA NA NA --; <1 NA

DW-TW-04 NA --–<1 (1) --–<1 (1) NA NA NA <1–<1 (7) NA

NA --; -- --; -- NA NA NA --; <1 NA

DW-TW-05 NA --–<1 (1) --–<1 (1) NA NA NA <1–<1 (7) NA

NA --; -- --; -- NA NA NA --; <1 NA

DW-TW-06 NA --–<1 (1) --–<1 (1) NA NA NA <1–<1 (7) NA

NA --; -- --; -- NA NA NA --; <1 NA

DW-TW-07 NA --–<1 (1) --–<1 (1) NA NA NA <1–<1 (7) NA

NA --; -- --; -- NA NA NA --; <1 NA

DW-TW-08 NA --–<1 (1) --–<1 (1) NA NA NA <1–<1 (4) NA

NA --; -- --; -- NA NA NA --; -- NA

DW-TW-09 NA --–<1 (1) --–<1 (1) NA NA NA <1–<1 (4) NA

NA --; -- --; -- NA NA NA --; -- NA

RRW-01 NA --–<1 (1) --–<1 (1) NA NA NA <1–<1 (7) NA

NA --; -- --; -- NA NA NA --; <1 NA

RRW-02 NA --–<1 (1) --–<1 (1) NA NA NA <1–<1 (7) NA

NA --; -- --; -- NA NA NA --; <1 NA

RRW-03 NA NA NA NA NA NA <1–<1 (5) NA

NA NA NA NA NA NA --; -- NA
130 Water Quality in the Equus Beds Aquifer and the Little Arkansas River, South-Central Kansas Table A–7. Summary of bacteria and viral indicator detections and triazine herbicide concentrations in water samples collected as part of the Equus Beds Groundwater Recharge Project during 1995–2005.—Continued [cfu/100 mL, colony forming units per 100 milliliters; pfu/100 mL, plaque forming units per 100 milliliters; m-TEC, membrane-thermotolerant Escherichia coli; MF, membrane filter; col/100 mL, colonies per 100 milliliters; μg/L, micrograms per liter; ELISA, enzyme-linked immunosorbent assay; --, not determined; MCLG, Maximum Contaminant Level Goal; MCL, Maximum Contaminant Level; <, less than; NA, not analyzed. The first set of numbers under each heading, for example 99–3,350, indicates the range in concentration. The number in parentheses () indicates the number of samples collected. The numbers below indicate the average followed by the median. Asterisk * is value estimated by using a log-probability regres- sion to predict the values of data below the detection level.] Data-collection site (fig. 6) Total coliform (col/100 mL) Atrazine (μg/L) Triazine screen, ELISA (μg/L as atrazine) Drinking-water criteria 0 (MCLG) 3.0 (MCL) -- Reporting level 1.0 0.05 0.1 Background wells EB-142-A3 <2–<2 (3) <0.001–0.002 (3) <0.1–<0.1 (4) --; -- --; -- --; -- Sedgwick well <1–490 (45) <0.001–0.006 (17) <0.01–0.3 (47) 23.4*; <1 --; <0.007 --; <0.1 City well-Sedgwick --–<10 (1) --–<0.017 (1) --–<0.1 (1) --; -- --; -- --; -- TH-02-95 <1–22 (25) <0.001–<0.05 (8) <0.01–0.1 (26) 1.29*; <1 --; <0.007 --; <0.1 TH-06-95 <1–20 (27) <0.001–0.004 (9) <0.1–0.3 (28) 2.31*; <1 --; <0.017 --; <0.1 TH-10-95 <1–19 (26) <0.001–<0.05 (9) <0.01–0.1 (28) 1.30*; <1 --; <0.007 --; <0.1 TH-12-95 --–<2 (1) --–<0.017 (1) <0.01–<0.1 (2) --; -- --; -- --; -- TH-08-A1 <1–8 (7) 0.013–1.6 (6) <0.1–2 (9) --; <2 0.56; 0.11 --; <0.1 TH-08-A2 <1–3 (10) <0.05–0.17 (5) <0.1–0.1 (10) --; <1 --; -- --; <0.1 TH-08-A3 <1–636 (23) <0.007–0.02 (9) <0.1–0.2 (23) 28.7*; <1 0.011*; 0.01 --; <0.1 TH-08-A4 --–<1 (1) --–0.006 (1) --–<0.1 (1) --; -- --; -- --; -- TH-08-A5 <1–4 (12) <0.007–0.007 (4) <0.1–0.1 (12) --; <1 --; -- --; <0.1 Alta Mills <1–33 (23) <0.05–0.171 (9) <0.1–1 (23) 4.63*; 1 0.089*; 0.09 0.3*; 0.2 Aquifer storage and recovery prototype wells DW-TW-01 <1–15 (7) <0.007–<0.05 (5) <0.1–<0.1 (7) --; <1 --; -- --; <0.1 DW-TW-02 <1–8 (7) <0.007–<0.05 (4) <0.1–<0.1 (7) --; 1 --; -- --; <0.1 DW-TW-03 <1–48 (7) <0.007–<0.05 (5) <0.1–0.1 (7) --; <1 --; -- --; <0.1 DW-TW-04 <1–6 (7) <0.007–<0.05 (4) <0.1–0.2 (7) --; <1 --; -- --; <0.1 DW-TW-05 <1–10 (7) <0.007–<0.05 (5) <0.1–<0.1 (7)

--; <1 --; -- --; <0.1

DW-TW-06 <1–8 (7) <0.007–<0.05 (5) <0.1–0.1 (7)

--; <1 --; -- --; <0.1

DW-TW-07 <1–28 (7) <0.007–<0.05 (5) <0.1–0.8 (7)

--; <1 --; -- --; <0.1

DW-TW-08 <1–224 (4) <0.007–<0.007 (3) <0.1–<0.1 (4)

--; -- --; -- --; --

DW-TW-09 <1–140 (4) <0.007–<0.007 (3) <0.1–<0.1 (4)

--; -- --; -- --; --

RRW-01 <1–98 (7) <0.007–<0.05 (5) <0.1–0.1 (7)

--; <1 --; -- --; <0.1

RRW-02 <1–12 (7) <0.007–<0.05 (5) <0.1–0.3 (7)

--; <1 --; -- --; <0.1

RRW-03 <1–8 (5) <0.007–<0.05 (4) <0.1–<0.1 (5)

--; -- --; -- --; --
Appendix 13

1

Table A–7. Summary of bacteria and viral indicator detections and triazine herbicide concentrations in water samples collected as part of the Equus Beds Groundwater 

Recharge Project during 1995–2005.—Continued

[cfu/100 mL, colony forming units per 100 milliliters; pfu/100 mL, plaque forming units per 100 milliliters; m-TEC, membrane-thermotolerant Escherichia coli; MF, membrane filter; col/100 mL, colonies per 100 milliliters; μg/L, micrograms per liter; ELISA, enzyme-linked immunosorbent assay; --, not determined; MCLG, Maximum Contaminant Level Goal; MCL, Maximum Contaminant Level; <, less than; NA, not analyzed. The first set of numbers under each heading, for example 99–3,350, indicates the range in concentration. The number in parentheses () indicates the number of samples collected. The numbers below indicate the average followed by the median. Asterisk * is value estimated by using a log-probability regression to predict the values of data below the detection level.]

Data-collection site

(fig. 6)

Clostridium 

perfringens 

(cfu/100 mL)

Coliphage, Escherichia 

coli, C13 host 

(pfu/100 mL)

Coliphage, Escherichia 

coli, Famp host 

(pfu/100 mL)

Enterococci

(cfu/100 mL)

Escherichia coli, modified 

m-TEC MF method

(cfu/100 mL)

Escherichia coli, m-TEC 

MF method

(cfu/100 mL)

Fecal coliform

(col/100 mL)

Fecal streptococci

(cfu/100 mL)

Drinking-water criteria -- -- -- -- -- -- -- --

Reporting level 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0

Shallow index wells

IW-01A --–<1 (1) --–<1 (1) --–<1 (1) NA NA --–<1 (1) <1–<1 (8) NA

--; -- --; -- --; -- NA NA --; -- --; <1 NA

IW-02A --–<1 (1) --–<1 (1) --–<1 (1) NA NA NA <1–<1 (7) NA

--; -- --; -- --; -- NA NA NA --; <1 NA

IW-03A --–<1 (1) --–1 (1) --–<1 (1) NA NA --–<1 (1) <1–<1 (8) NA

--; -- --; -- --; -- NA NA --; -- --; <1 NA

IW-04A --–<1 (1) --–<1 (1) --–<1 (1) NA NA NA <1–10 (7) NA

--; -- --; -- --; -- NA NA NA --; <1 NA

IW-05A --–<1 (1) --–<1 (1) --–<1 (1) NA --–<1 (1) NA <1–24 (8) NA

--; -- --; -- --; -- NA --; -- NA --; <1 NA

IW-06A --–<1 (1) --–<1 (1) --–<1 (1) NA NA NA <1–<1 (7) NA

--; -- --; -- --; -- NA NA NA --; <1 NA

IW-07A --–<1 (1) --–<1 (1) --–<1 (1) NA NA NA <1–<1 (7) NA

--; -- --; -- --; -- NA NA NA --; <1 NA

IW-08A --–<1 (1) --–<1 (1) --–<1 (1) NA --–<1 (1) --–<1 (1) <1–4 (9) NA

--; -- --; -- --; -- NA --; -- --; -- --; <1 NA

IW-09A --–<1 (1) --–<1 (1) --–<1 (1) NA NA NA <1–1 (7) NA

--; -- --; -- --; -- NA NA NA --; <1 NA

IW-10A --–1 (1) --–<1 (1) --–<1 (1) NA NA NA <1–<1 (7) NA

--; -- --; -- --; -- NA NA NA --; <1 NA

IW-11A-2 --–<1 (1) <1–<1 (2) <1–<1 (2) NA NA NA <1–<1 (7) NA

--; -- --; -- --; -- NA NA NA --; <1 NA

IW-12A --–<1 (1) --–<1 (1) --–<1 (1) NA --–<1 (1) --–<1 (1) <1–<1 (10) NA

--; -- --; -- --; -- NA --; -- --; -- --; <1 NA

IW-13A --–<1 (1) <1–<1 (2) <1–<1 (2) NA NA NA <1–<1 (7) NA

--; -- --; -- --; -- NA NA NA --; <1 NA

IW-14A --–<1 (1) <1–<1 (2) <1–<1 (2) NA NA NA <1–<1 (8) NA

--; -- --; -- --; -- NA NA NA --; <1 NA

IW-15A --–<1 (1) --–<1 (1) --–<1 (1) NA NA NA <1–<1 (7) NA

--; -- --; -- --; -- NA NA NA --; <1 NA

IW-16A --–<1 (1) <1–<1 (2) <1–<1 (2) NA NA NA <1–<1 (7) NA

--; -- --; -- --; -- NA NA NA --; <1 NA

IW-17A --–<1 (1) --–<1 (1) --–<1 (1) NA NA NA <1–<1 (7) NA

--; -- --; -- --; -- NA NA NA --; <1 NA

IW-18A --–<1 (1) --–<1 (1) --–1 (1) NA NA NA <1–<1 (7) NA

--; -- --; -- --; -- NA NA NA --; <1 NA

IW-19A --–<1 (1) --–<1 (1) --–<1 (1) NA NA NA <1–<1 (7) NA

--; -- --; -- --; -- NA NA NA --; <1 NA

IW-20A <1–<1 (2) <1–<1 (2) <1–<1 (2) NA NA --–<1 (1) <1–120 (8) NA

--; -- --; -- --; -- NA NA --; -- --; <1 NA

IW-21A --–<1 (1) <1–<1 (2) <1–<1 (2) NA NA NA <1–<1 (7) NA

--; -- --; -- --; -- NA NA NA --; <1 NA

IW-22A --–<1 (1) --–<1 (1) --–<1 (1) NA NA --–<1 (1) <1–<1 (8) NA

--; -- --; -- --; -- NA NA --; -- --; <1 NA

IW-23A --–<1 (1) --–<1 (1) --–<1 (1) NA NA NA <1–2 (7) NA

--; -- --; -- --; -- NA NA NA --; <1 NA

IW-24A --–<1 (1) --–<1 (1) --–<1 (1) NA NA --–<1 (1) <1–<1 (8) NA

--; -- --; -- --; -- NA NA --; -- --; <1 NA

IW-25A --–<1 (1) --–<1 (1) --–<1 (1) NA NA NA <1–<1 (7) NA

--; -- --; -- --; -- NA NA NA --; <1 NA

IW-26A --–<1 (1) --–<1 (1) --–<1 (1) NA NA NA <1–<1 (7) NA

--; -- --; -- --; -- NA NA NA --; <1 NA

IW-27A --–<1 (1) --–<1 (1) --–<1 (1) NA NA NA <1–<20 (7) NA

--; -- --; -- --; -- NA NA NA --; <1 NA

IW-28A --–<1 (1) <1–<1 (2) <1–<1 (2) NA NA NA <1–<1 (7) NA

--; -- --; -- --; -- NA NA NA --; <1 NA
132 Water Quality in the Equus Beds Aquifer and the Little Arkansas River, South-Central Kansas Table A–7. Summary of bacteria and viral indicator detections and triazine herbicide concentrations in water samples collected as part of the Equus Beds Groundwater Recharge Project during 1995–2005.—Continued [cfu/100 mL, colony forming units per 100 milliliters; pfu/100 mL, plaque forming units per 100 milliliters; m-TEC, membrane-thermotolerant Escherichia coli; MF, membrane filter; col/100 mL, colonies per 100 milliliters; μg/L, micrograms per liter; ELISA, enzyme-linked immunosorbent assay; --, not determined; MCLG, Maximum Contaminant Level Goal; MCL, Maximum Contaminant Level; <, less than; NA, not analyzed. The first set of numbers under each heading, for example 99–3,350, indicates the range in concentration. The number in parentheses () indicates the number of samples collected. The numbers below indicate the average followed by the median. Asterisk * is value estimated by using a log-probability regression to predict the values of data below the detection level.] Data-collection site (fig. 6) Total coliform (col/100 mL) Atrazine (μg/L) Triazine screen, ELISA (μg/L as atrazine) Drinking-water criteria 0 (MCLG) 3.0 (MCL) -- Reporting level 1.0 0.05 0.1 Shallow index wells IW-01A <1–7 (7) <0.007–<0.05 (3) <0.1–<0.1 (7) --; <1 --; -- --; <0.1 IW-02A <1–2 (7) <0.007–<0.007 (2) <0.1–<0.1 (7) --; <1 --; -- --; <0.1 IW-03A <1–3 (7) <0.007–<0.05 (4) <0.1–<0.1 (7) --; <1 --; -- --; <0.1 IW-04A <4–84 (7) 0.07–1.2 (5) <0.1–2 (7) 14.6*; 4 --; -- 0.7*; 0.3 IW-05A <1–156 (7) --–0.005 (1) <0.1–<0.1 (7) --; <1 --; -- --; <0.1 IW-06A <1–14 (7) 0.05–0.16 (6) <0.1–0.3 (7) --; <1 0.09; 0.07 0.2*; 0.2 IW-07A <1–3 (7) <0.007–<0.05 (2) <0.1–<0.1 (7) --; <1 --; -- --; <0.1 IW-08A <1–60 (7) <0.05–0.028 (4) <0.1–<0.1 (7) --; <1 --; -- --; <0.1 IW-09A <1–99 (7) 0.009–0.011 (2) <0.1–<0.1 (7) --; 2 --; -- --; <0.1 IW-10A <1–12 (7) 0.21–0.27 (3) 0.2–0.5 (7) --; <1 --; -- 0.3; 0.3 IW-11A-2 <1–7 (7) <0.007–<0.007 (2) <0.1–<0.1 (7) --; <1 --; -- --; <0.1 IW-12A <1–324 (8) <0.05–0.064 (4) <0.1–<0.1 (8) --; <1 --; -- --; <0.1 IW-13A <1–15 (7) 0.005–0.005 (2) <0.1–<0.1 (7) --; <1 --; -- --; <0.1 IW-14A <1–18 (8) 0.004–0.006 (2) <0.1–<0.1 (8) --; <1 --; -- --; <0.1 IW-15A <1–10 (7) --–0.022 (1) <0.1–<0.1 (7) --; <1 --; -- --; <0.1 IW-16A <1–<1 (7) <0.007–<0.007 (2) <0.1–<0.1 (7) --; <1 --; -- --; <0.1 IW-17A <1–7 (7) <0.007–<0.007 (2) <0.1–<0.1 (7) --; <1 --; -- --; <0.1 IW-18A <1–10 (7) 0.006–0.007 (2) <0.1–<0.1 (7) --; <1 --; -- --; <0.1 IW-19A <1–1 (7) --–0.024 (1) <0.1–<0.1 (7) --; <1 --; -- --; <0.1 IW-20A <1–<1 (7) <0.007–<0.05 (5) <0.1–<0.1 (8)

--; <1 --; -- --; <0.1

IW-21A <1–1 (7) 0.009–0.011 (2) <0.1–<0.1 (7)

--; <1 --; -- --; <0.1

IW-22A <1–2 (7) 0.047–0.09 (5) <0.1–0.2 (7)

--; <1 --; -- --; <0.1

IW-23A <1–18 (7) <0.007–<0.007 (2) <0.1–<0.1 (7)

--; <1 --; -- --; <0.1

IW-24A <1–10 (7) <0.007–<0.05 (5) <0.1–<0.1 (7)

--; <1 --; -- --; <0.1

IW-25A <1–12 (7) 0.007–0.013 (2) <0.1–0.3 (7)

--; <1 --; -- --; <0.1

IW-26A <1–37 (7) --–<0.007 (1) <0.1–<0.1 (7)

--; <1 --; -- --; <0.1

IW-27A <1–300 (7) <0.007–<0.007 (2) <0.1–<0.1 (7)

--; 3 --; -- --; <0.1

IW-28A <1–26 (7) 0.005–0.009 (2) <0.1–<0.1 (7)

--; <1 --; -- --; <0.1
Appendix 13

3

Table A–7. Summary of bacteria and viral indicator detections and triazine herbicide concentrations in water samples collected as part of the Equus Beds Groundwater 

Recharge Project during 1995–2005.—Continued

[cfu/100 mL, colony forming units per 100 milliliters; pfu/100 mL, plaque forming units per 100 milliliters; m-TEC, membrane-thermotolerant Escherichia coli; MF, membrane filter; col/100 mL, colonies per 100 milliliters; μg/L, micrograms per liter; ELISA, enzyme-linked immunosorbent assay; --, not determined; MCLG, Maximum Contaminant Level Goal; MCL, Maximum Contaminant Level; <, less than; NA, not analyzed. The first set of numbers under each heading, for example 99–3,350, indicates the range in concentration. The number in parentheses () indicates the number of samples collected. The numbers below indicate the average followed by the median. Asterisk * is value estimated by using a log-probability regression to predict the values of data below the detection level.]

Data-collection site

(fig. 6)

Clostridium 

perfringens 

(cfu/100 mL)

Coliphage, Escherichia 

coli, C13 host 

(pfu/100 mL)

Coliphage, Escherichia 

coli, Famp host 

(pfu/100 mL)

Enterococci

(cfu/100 mL)

Escherichia coli, modified 

m-TEC MF method

(cfu/100 mL)

Escherichia coli, m-TEC 

MF method

(cfu/100 mL)

Fecal coliform

(col/100 mL)

Fecal streptococci

(cfu/100 mL)

Drinking-water criteria -- -- -- -- -- -- -- --

Reporting level 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0

Shallow index wells—Continued

IW-29A --–<1 (1) --–<1 (1) --–<1 (1) NA NA NA <1–<2 (8) NA

--; -- --; -- --; -- NA NA NA --; <1 NA

IW-30A --–<1 (1) --–<1 (1) --–<1 (1) NA NA --–1 (1) <1–1 (8) NA

--; -- --; -- --; -- NA NA --; -- --; <1 NA

IW-31A --–<1 (1) --–<1 (1) --–<1 (1) NA NA NA <1–<1 (7) NA

--; -- --; -- --; -- NA NA NA --; <1 NA

IW-32A --–<1 (1) <1–<1 (2) <1–<1 (2) NA NA NA <1–<1 (7) NA

--; -- --; -- --; -- NA NA NA --; <1 NA

IW-33A --–<1 (1) --–<1 (1) --–<1 (1) NA --–<1 (1) NA <1–<1 (8) NA

--; -- --; -- --; -- NA --; -- NA --; <1 NA

IW-34A --–<1 (1) <1–<1 (2) <1–<1 (2) NA NA NA <1–<1 (7) NA

--; -- --; -- --; -- NA NA NA --; <1 NA

IW-35A --–<1 (1) <1–<1 (2) <1–<1 (2) NA NA NA <1–<1 (8) NA

--; -- --; -- --; -- NA NA NA --; <1 NA

IW-36A --–<1 (1) --–<1 (1) --–<1 (1) NA NA NA <1–<1 (8) NA

--; -- --; -- --; -- NA NA NA --; <1 NA

IW-37A --–<1 (1) --–<1 (1) --–<1 (1) NA --–1 (1) --–<1 (1) <1–1 (9) NA

--; -- --; -- --; -- NA --; -- --; -- --; <1 NA

IW-38A --–<1 (1) --–<1 (1) --–<1 (1) NA NA NA <1–<1 (7) NA

--; -- --; -- --; -- NA NA NA --; <1 NA

Deep index wells

IW-01C --–<1 (1) --–<1 (1) --–<1 (1) NA NA --–<1 (1) <1–<1 (8) NA

--; -- --; -- --; -- NA NA --; -- --; <1 NA

IW-02C --–<1 (1) --–<1 (1) --–<1 (1) NA NA NA <1–<1 (7) NA

--; -- --; -- --; -- NA NA NA --; <1 NA

IW-03C --–<1 (1) --–<1 (1) --–<1 (1) NA NA --–<1 (1) <1–<1 (8) NA

--; -- --; -- --; -- NA NA --; -- --; <1 NA

IW-04C --–<1 (1) --–<1 (1) --–<1 (1) NA NA NA <1–<1 (7) NA

--; -- --; -- --; -- NA NA NA --; <1 NA

IW-05C --–<1 (1) --–<1 (1) --–<1 (1) NA NA NA <1–2 (7) NA

--; -- --; -- --; -- NA NA NA --; <1 NA

IW-06C --–<1 (1) --–<1 (1) --–<1 (1) NA NA --–<1 (1) <1–<1 (8) NA

--; -- --; -- --; -- NA NA --; -- --; <1 NA

IW-07C --–<1 (1) --–<1 (1) --–<1 (1) NA NA NA <1–<1 (7) NA

--; -- --; -- --; -- NA NA NA --; <1 NA

IW-08C --–<1 (1) --–<1 (1) --–<1 (1) NA NA --–<1 (1) <1–<1 (9) NA

--; -- --; -- --; -- NA NA --; -- --; <1 NA

IW-09C --–<1 (1) --–<1 (1) --–<1 (1) NA NA NA <1–<1 (7) NA

--; -- --; -- --; -- NA NA NA --; <1 NA

IW-10C --–<1 (1) --–<1 (1) --–<1 (1) NA NA NA <1–<1 (7) NA

--; -- --; -- --; -- NA NA NA --; <1 NA

IW-11C --–<1 (1) <1–<1 (2) <1–<1 (2) NA NA NA <1–<1 (7) NA

--; -- --; -- --; -- NA NA NA --; <1 NA

IW-12C --–<1 (1) --–<1 (1) --–<1 (1) NA --–<1 (1) --–<1 (1) <1–21 (10) NA

--; -- --; -- --; -- NA --; -- --; -- --; <1 NA

IW-13C --–<1 (1) <1–<1 (2) <1–<1 (2) NA NA NA <1–<1 (7) NA

--; -- --; -- --; -- NA NA NA --; <1 NA

IW-14C --–<1 (1) <1–<1 (2) <1–<1 (2) NA NA NA <1–<1 (8) NA

--; -- --; -- --; -- NA NA NA --; <1 NA
134 Water Quality in the Equus Beds Aquifer and the Little Arkansas River, South-Central Kansas Table A–7. Summary of bacteria and viral indicator detections and triazine herbicide concentrations in water samples collected as part of the Equus Beds Groundwater Recharge Project during 1995– 2005.—Continued [cfu/100 mL, colony forming units per 100 milliliters; pfu/100 mL, plaque forming units per 100 milliliters; m-TEC, membrane-thermotol- erant Escherichia coli; MF, membrane filter; col/100 mL, colonies per 100 milliliters; μg/L, micrograms per liter; ELISA, enzyme-linked immunosorbent assay; --, not determined; MCLG, Maximum Contaminant Level Goal; MCL, Maximum Contaminant Level; <, less than; NA, not analyzed. The first set of numbers under each heading, for example 99–3,350, indicates the range in concentration. The number in parentheses () indicates the number of samples collected. The numbers below indicate the average followed by the median. Asterisk * is value estimated by using a log-probability regression to predict the values of data below the detection level.] Data-collection site (fig. 6) Total coliform (col/100 mL) Atrazine (μg/L) Triazine screen, ELISA (μg/L as atrazine) Drinking-water criteria 0 (MCLG) 3.0 (MCL) -- Reporting level 1.0 0.05 0.1 Shallow index wells—Continued IW-29A <1–6 (8) --–0.015 (1) <0.1–0.1 (8) --; <1 --; -- --; <0.1 IW-30A <1–368 (7) <0.05–0.05 (5) <0.1–0.1 (7) --; <1 --; -- --; <0.1 IW-31A <1–6 (7) 0.06–0.212 (4) <0.1–0.4 (7) --; 2 --; -- 0.2*; 0.1 IW-32A <1–78 (7) <0.007–0.004 (2) <0.1–<0.1 (7) --; <1 --; -- --; <0.1 IW-33A <1–83 (7) <0.05–0.031 (2) <0.1–0.2 (7) --; <1 --; -- --; <0.1 IW-34A <1–136 (7) 0.004–0.006 (2) <0.1–<0.1 (7) --; <1 --; -- --; <0.1 IW-35A <1–34 (8) 0.051–0.054 (2) <0.1–0.1 (8) --; <1 --; -- --; <0.1 IW-36A <1–6 (8) <0.05–0.13 (5) <0.1–0.3 (8) 1.84*; 1 --; -- 0.1*; 0.1 IW-37A <1–54 (7) <0.007–<0.05 (4) <0.1–<0.1 (7) --; 2 --; -- --; <0.1 IW-38A <1–11 (7) <0.007–<0.007 (2) <0.1–<0.1 (7) --; <1 --; -- --; <0.1 Deep index wells IW-01C <1–4 (7) <0.007–0.06 (3) <0.1–<0.1 (7) --; <1 --; -- --; <0.1 IW-02C <1–9 (7) --–<0.007 (1) <0.1–<0.1 (7) --; <1 --; -- --; <0.1 IW-03C <1–6 (7) <0.007–<0.05 (3) <0.1–<0.1 (7) --; <1 --; -- --; <0.1 IW-04C <1–<1 (7) --–<0.007 (1) <0.1–<0.1 (7) --; <1 --; -- --; <0.1 IW-05C <1–7 (7) -- <0.1–<0.1 (7) --; <1 -- --; <0.1 IW-06C <1–1 (7) <0.007–<0.05 (3) <0.1–<0.1 (7) --; <1 --; -- --; <0.1 IW-07C <1–1 (7) --–0.007 (1) <0.1–<0.1 (7)

--; <1 --; -- --; <0.1

IW-08C <1–1 (8) <0.007–<0.05 (3) <0.1–<0.1 (8)

--; <1 --; -- --; <0.1

IW-09C <1–20 (7) --–<0.007 (1) <0.1–<0.1 (7)

--; <1 --; -- --; <0.1

IW-10C <1–15 (7) -- <0.1–<0.1 (7)

--; <1 -- --; <0.1

IW-11C <1–5 (7) --–<0.007 (1) <0.1–<0.1 (7)

--; <1 --; -- --; <0.1

IW-12C <1–51 (8) <0.007–<0.05 (3) <0.1–<0.1 (8)

--; <1 --; -- --; <0.1

IW-13C <1–<1 (7) --–<0.007 (1) <0.1–<0.1 (7)

--; <1 --; -- --; <0.1

IW-14C <1–2 (8) --–0.009 (1) <0.1–<0.1 (8)

--; <1 --; -- --; <0.1
Appendix 13

5

Table A–7. Summary of bacteria and viral indicator detections and triazine herbicide concentrations in water samples collected as part of the Equus Beds Groundwater 

Recharge Project during 1995–2005.—Continued

[cfu/100 mL, colony forming units per 100 milliliters; pfu/100 mL, plaque forming units per 100 milliliters; m-TEC, membrane-thermotolerant Escherichia coli; MF, membrane filter; col/100 mL, colonies per 100 milliliters; μg/L, micrograms per liter; ELISA, enzyme-linked immunosorbent assay; --, not determined; MCLG, Maximum Contaminant Level Goal; MCL, Maximum Contaminant Level; <, less than; NA, not analyzed. The first set of numbers under each heading, for example 99–3,350, indicates the range in concentration. The number in parentheses () indicates the number of samples collected. The numbers below indicate the average followed by the median. Asterisk * is value estimated by using a log-probability regression to predict the values of data below the detection level.]

Data-collection site

(fig. 6)

Clostridium 

perfringens 

(cfu/100 mL)

Coliphage, Escherichia 

coli, C13 host 

(pfu/100 mL)

Coliphage, Escherichia 

coli, Famp host 

(pfu/100 mL)

Enterococci

(cfu/100 mL)

Escherichia coli, modified 

m-TEC MF method

(cfu/100 mL)

Escherichia coli, m-TEC 

MF method

(cfu/100 mL)

Fecal coliform

(col/100 mL)

Fecal streptococci

(cfu/100 mL)

Drinking-water criteria -- -- -- -- -- -- -- --Reporting level 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0

Deep index wells—Continued

IW-15C --–<1 (1) --–<1 (1) --–<1 (1) NA NA NA <1–<1 (7) NA

--; -- --; -- --; -- NA NA NA --; <1 NA

IW-16C --–<1 (1) <1–<1 (2) <1–<1 (2) NA NA NA <1–<1 (7) NA

--; -- --; -- --; -- NA NA NA --; <1 NA

IW-17C --–<1 (1) --–<1 (1) --–<1 (1) NA NA NA <1–<1 (7) NA

--; -- --; -- --; -- NA NA NA --; <1 NA

IW-18C --–<1 (1) --–<1 (1) --–<1 (1) NA NA NA <1–<1 (7) NA

--; -- --; -- --; -- NA NA NA --; <1 NA

IW-19C --–<1 (1) --–<1 (1) --–<1 (1) NA NA NA <1–<1 (7) NA

--; -- --; -- --; -- NA NA NA --; <1 NA

IW-20C --–<1 (1) --–<1 (1) --–<1 (1) NA NA --–<1 (1) <1–<1 (9) NA

--; -- --; -- --; -- NA NA --; -- --; <1 NA

IW-21C --–<1 (1) <1–<1 (2) <1–<1 (2) NA NA NA <1–<1 (8) NA

--; -- --; -- --; -- NA NA NA --; <1 NA

IW-22C --–<1 (1) --–<1 (1) --–<1 (1) NA NA --–<1 (1) <1–<1 (8) NA

--; -- --; -- --; -- NA NA --; -- --; <1 NA

IW-23C --–<1 (1) --–<1 (1) --–<1 (1) NA NA NA <1–<1 (7) NA

--; -- --; -- --; -- NA NA NA --; <1 NA

IW-24C --–<1 (1) --–<1 (1) --–<1 (1) NA NA --–<1 (1) <1–<1 (8) NA

--; -- --; -- --; -- NA NA --; -- --; <1 NA

IW-25C --–<1 (1) --–<1 (1) --–<1 (1) NA NA NA <1–<1 (8) NA

--; -- --; -- --; -- NA NA NA --; <1 NA

IW-26C --–<1 (1) --–<1 (1) --–<1 (1) NA NA NA <1–<1 (6) NA

--; -- --; -- --; -- NA NA NA --; <1 NA

IW-27C --–<1 (1) --–<1 (1) --–<1 (1) NA NA NA <1–<20 (7) NA

--; -- --; -- --; -- NA NA NA --; <1 NA

IW-28C --–<1 (1) <1–<1 (2) <1–<1 (2) NA NA NA <1–<1 (7) NA

--; -- --; -- --; -- NA NA NA --; <1 NA

IW-29C --–<1 (1) --–<1 (1) --–<1 (1) NA NA NA <1–<1 (7) NA

--; -- --; -- --; -- NA NA NA --; <1 NA

IW-30C --–<1 (1) --–<1 (1) --–<1 (1) NA NA --–1 (1) <1–1 (9) NA

--; -- --; -- --; -- NA NA --; -- --; <1 NA

IW-31C --–<1 (1) --–<1 (1) --–<1 (1) NA NA NA <1–<1 (7) NA

--; -- --; -- --; -- NA NA NA --; <1 NA

IW-32C --–<1 (1) <1–<1 (2) <1–<1 (2) NA NA NA <1–<1 (7) NA

--; -- --; -- --; -- NA NA NA --; <1 NA

IW-33C --–<1 (1) --–<1 (1) --–<1 (1) NA NA NA <1–<1 (7) NA

--; -- --; -- --; -- NA NA NA --; <1 NA

IW-34C --–<1 (1) <1–<1 (2) <1–<1 (2) NA NA NA <1–4 (7) NA

--; -- --; -- --; -- NA NA NA --; <1 NA

IW-35C --–<1 (1) <1–<1 (2) <1–<1 (2) NA NA NA <1–<1 (8) NA

--; -- --; -- --; -- NA NA NA --; <1 NA

IW-36C --–<1 (1) --–<1 (1) --–<1 (1) NA NA NA <1–<1 (7) NA

--; -- --; -- --; -- NA NA NA --; <1 NA

IW-37C --–<1 (1) --–<1 (1) --–<1 (1) NA --–<1 (1) --–<1 (1) <1–<1 (9) NA

--; -- --; -- --; -- NA --; -- --; -- --; <1 NA

IW-38C --–<1 (1) --–<1 (1) --–<1 (1) NA NA NA <1–<1 (7) NA

--; -- --; -- --; -- NA NA NA --; <1 NA
136 Water Quality in the Equus Beds Aquifer and the Little Arkansas River, South-Central Kansas Table A–7. Summary of bacteria and viral indicator detections and triazine herbicide concentrations in water samples collected as part of the Equus Beds Groundwater Recharge Project during 1995–2005.—Continued [cfu/100 mL, colony forming units per 100 milliliters; pfu/100 mL, plaque forming units per 100 milliliters; m-TEC, membrane-thermotolerant Escherichia coli; MF, membrane filter; col/100 mL, colonies per 100 milliliters; μg/L, micrograms per liter; ELISA, enzyme-linked immunosorbent assay; --, not determined; MCLG, Maximum Con- taminant Level Goal; MCL, Maximum Contaminant Level; <, less than; NA, not analyzed. The first set of numbers under each heading, for example 99–3,350, indicates the range in concentration. The number in parentheses () indi- cates the number of samples collected. The numbers below indicate the average followed by the median. Asterisk * is value estimated by using a log-probability regression to predict the values of data below the detection level.] Data-collection site (fig. 6) Total coliform (col/100 mL) Atrazine (μg/L) Triazine screen, ELISA (μg/L as atrazine) Drinking-water criteria 0 (MCLG) 3.0 (MCL) -- Reporting level 1.0 0.05 0.1 Deep index wells—Continued IW-15C <1–12 (7) -- <0.1–<0.1 (7) --; <1 -- --; <0.1 IW-16C <1–1 (7) --–0.004 (1) <0.1–<0.1 (7) --; <1 --; -- --; <0.1 IW-17C <1–8 (7) --–<0.007 (1) <0.1–<0.1 (7) --; <1 --; -- --; <0.1 IW-18C <1–46 (7) --–<0.007 (1) <0.1–<0.1 (7) --; <1 --; -- --; <0.1 IW-19C <1–<1 (7) -- <0.1–<0.1 (7) --; <1 -- --; <0.1 IW-20C <1–1 (8) <0.007–<0.05 (3) <0.1–<0.1 (8) --; <1 --; -- --; <0.1 IW-21C <1–<1 (8) --–<0.007 (1) <0.1–<0.1 (8) --; <1 --; -- --; <0.1 IW-22C <1–4 (7) <0.05–0.013 (3) <0.1–0.1 (7) --; <1 --; -- --; <0.1 IW-23C <1–<1 (7) --–<0.007 (1) <0.1–<0.1 (6) --; <1 --; -- --; <0.1 IW-24C <1–2 (7) <0.007–<0.05 (3) <0.1–<0.1 (7) --; <1 --; -- --; <0.1 IW-25C <1–6 (8) --–0.013 (1) <0.1–<0.1 (8) --; <1 --; -- --; <0.1 IW-26C <1–4 (6) -- <0.1–<0.1 (6) --; <1 -- --; <0.1 IW-27C <1–84 (7) --–<0.007 (1) <0.1–<0.1 (7) --; <1 --; -- --; <0.1 IW-28C <1–1 (7) --–<0.007 (1) <0.1–<0.1 (7) --; <1 --; -- --; <0.1 IW-29C <1–1 (7) -- <0.1–<0.1 (7) --; <1 -- --; <0.1 IW-30C <1–13 (8) <0.05–<0.05 (2) <0.1–<0.1 (8) --; <1 --; -- --; <0.1 IW-31C <1–2 (7) --–<0.007 (1) <0.1–<0.1 (7) --; <1 --; -- --; <0.1

IW-32C <1–3 (7) --–0.004 (1) <0.1–<0.1 (7)

--; <1 --; -- --; <0.1

IW-33C <1–7 (7) -- <0.1–<0.1 (7)

--; <1 -- --; <0.1

IW-34C <1–10 (7) --–0.005 (1) <0.1–<0.1 (7)

--; <1 --; -- --; <0.1

IW-35C <1–41 (8) --–<0.007 (1) <0.1–<0.1 (8)

--; <1 --; -- --; <0.1

IW-36C <1–1 (7) 0.035–0.07 (3) <0.1–0.3 (7)

--; <1 --; -- --; <0.1

IW-37C <1–26 (7) <0.05–<0.05 (2) <0.1–<0.1 (7)

--; <1 --; -- --; <0.1

IW-38C <1–5 (7) --–<0.007 (1) <0.1–<0.1 (7)

--; <1 --; -- --; <0.1
Appendix 13

7

Table A–8. Summary of radionuclide analysis in water samples collected as part of the Equus Beds Groundwater Recharge Project, 1995–2005.[μg/L, micrograms per liter; pCi/L, picocuries per liter; --, not determined; MCL, Maximum Contaminant Level; mrem/yr, millirem per year; <, less than, NA; not analyzed; The first set of numbers under each heading, for example 99–3,350, indicates the range in concentration. The number in parentheses () indicates the number of samples collected. The numbers below indicate the average followed by the median. Asterisk * is value estimated by using a logprobability regression to predict the values of data below the detection level.]

Data-collection site 

(fig. 6)

Alpha radioactivity 

2-sigma combined 

uncertainty, natural 

uranium curve 

(μg/L)

Alpha radioactivity 

2-sigma combined 

uncertainty, 

Thorium-230 curve 

(pCi/L)

Alpha radioactivity, 

Thorium-230 curve 

(pCi/L)

Beta radioactivity 

2-sigma combined 

uncertainty, 

Cesium-137 curve 

(pCi/L)

Beta radioactivity 

2-sigma combined 

uncertainty, 

Strontium-90/ 

Yttrium-90 curve 

(pCi/L)

Gross alpha 

radioactivity, 

natural uranium 

curve 

(μg/L)

Gross beta 

radioactivity, 

Cesium-137 curve 

(pCi/L)

Gross beta 

radioactivity, 

Strontium-90/ 

Yttrium-90 curve 

(pCi/L)

Uranium

(μg/L)

Drinking-water criteria -- -- -- -- -- 15 pCi/L (MCL) 4 mrem/yr (MCL) 4 mrem/yr (MCL) 30 (MCL)Reporting level -- -- 3.0 -- -- 3.0 4.0 4.0 --

Surface-water monitoring sites (Little Arkansas River)

7143672 2.9–9.7 (4) 2.1–5.3 (5) <3–3.5 (5) 2.2–9.5 (5) 1.7–3.7 (4) <3–6.3 (4) 7.6–20 (5) 5.8–8.8 (4) --–3.75 (1)

(near Halstead) --; -- --; -- --; -- --; -- --; -- --; -- --; -- --; -- --; --7144100 2.4–7.2 (4) 1.4–5.5 (6) <3–4.2 (6) 1.1–7.6 (6) 1.7–4.4 (4) <3–5.5 (4) 7–17 (6) 6.7–10 (4) --–3.68 (1)

(near Sedgwick) --; -- 52.53; 1.95 --; <3 3.77; 3.25 --; -- --; -- 10.9; 10.4 --; -- --; --

Diversion well site near Halstead

Diversion well --–3.9 (1) 1.8–4.1 (6) <3–8.9 (6) 2.1–5.2 (6) --–4.4 (1) --–<3 (1) <4–9.7 (6) --–6.6 (1) NA

--; -- 2.75; 2.85 --; <3 3.73; 4.05 --; -- --; -- --; 4.6 --; -- NA

EB-145-A1 1.9–12 (4) 1.3–5.8 (5) <3–7.3 (5) 2.1–7.5 (5) 1.6–3.7 (4) <3–17 (4) 8.5–18 (5) 5.8–10 (4) --–0.02 (1)

--; -- --; -- --; -- --; -- --; -- --; -- --; -- --; -- --; --

EB-145-A2 --–7.7 (1) --–2.4 (1) --–<3 (1) --–6.1 (1) --–4.2 (1) --–<3 (1) --–<4 (1) --–<4 (1) NA

--; -- --; -- --; -- --; -- --; -- --; -- --; -- --; -- NA

EB-145-A3 --–3.9 (1) --–2.9 (1) --–4 (1) --–1.9 (1) --–1.4 (1) --–5.3 (1) --–4.4 (1) --–<4 (1) NA

--; -- --; -- --; -- --; -- --; -- --; -- --; -- --; -- NA

EB-145-A4 NA NA NA NA NA NA NA NA NA

NA NA NA NA NA NA NA NA NA

EB-145-A5 NA NA NA NA NA NA NA NA NA

NA NA NA NA NA NA NA NA NA

EB-145-P-D5 1.4–1.6 (2) 1–3.1 (3) <3–3 (3) 0.98–2.5 (3) 0.74–0.89 (2) <3–<3 (2) <4–<4 (3) <4–<4 (2) NA

--; -- --; -- --; -- --; -- --; -- --; -- --; -- --; -- NA

Halstead recharge site

SMW-H4 NA 1.3–4.4 (5) <3–10 (5) 1.9–4.9 (5) NA NA <4–9 (5) NA NA

NA --; -- --; -- --; -- NA NA --; -- NA NA

SMW-H14 NA 1–3.9 (4) <3–5.5 (4) 4.1–4.7 (4) NA NA <4–9.6 (4) NA NA

NA --; -- --; -- --; -- NA NA --; -- NA NA

DMW-H1 NA 1.3–3.1 (5) <3–<3 (5) 2.2–4.8 (5) NA NA <4–4.8 (5) NA NA

NA --; -- --; -- --; -- NA NA --; -- NA NA

DMW-H13 NA 1.1–3.2 (4) <3–<3 (4) 3.5–4.9 (4) NA NA <4–6.6 (4) NA NA

NA --; -- --; -- --; -- NA NA --; -- NA NA

Sedgwick recharge site

Treated stream water NA 1.8–2.9 (4) <3–<3 (4) 1.2–4.1 (4) NA NA 5.4–10.5 (4) NA NA

NA --; -- --; -- --; -- NA NA --; -- NA NA

SMW-S11 NA 2.4–4.1 (3) <3–8.8 (3) 1.5–4.3 (3) NA NA 5–12.7 (3) NA NA

NA --; -- --; -- --; -- NA NA --; -- NA NA

SMW-S13 NA 2.5–3.2 (3) <3–3.7 (3) 1.6–2.2 (3) NA NA <4–5.3 (3) NA NA

NA --; -- --; -- --; -- NA NA --; -- NA NA

DMW-S10 NA 2.8–4.8 (4) <3–10.4 (4) 2.3–4.8 (4) NA NA 4.3–8.2 (4) NA NA

NA --; -- --; -- --; -- NA NA --; -- NA NA

DMW-S14 NA 2.8–3.2 (3) <3–<3 (3) 1.7–4.1 (3) NA NA <4–5.1 (3) NA NA

NA --; -- --; -- --; -- NA NA --; -- NA NA
138 Water Quality in the Equus Beds Aquifer and the Little Arkansas River, South-Central Kansas Table A–8. Summary of radionuclide analysis in water samples collected as part of the Equus Beds Groundwater Recharge Project, 1995–2005.—Continued [μg/L, micrograms per liter; pCi/L, picocuries per liter; --, not determined; MCL, Maximum Contaminant Level; mrem/yr, millirem per year; <, less than, NA; not analyzed. The first set of numbers under each heading, for example 99–3,350, indicates the range in concentration. The number in parentheses () indicates the number of samples collected. The numbers below indicate the average followed by the median. Asterisk * is value estimated by using a log- probability regression to predict the values of data below the detection level.] Data-collection site (fig. 6) Alpha radioactivity 2-sigma combined uncertainty, natural uranium curve (μg/L) Alpha radioactivity 2-sigma combined uncertainty, Thorium-230 curve (pCi/L) Alpha radioactivity, Thorium-230 curve (pCi/L) Beta radioactivity 2-sigma combined uncertainty, Cesium-137 curve (pCi/L) Beta radioactivity 2-sigma combined uncertainty, Strontium-90/ Yttrium-90 curve (pCi/L) Gross alpha radioactivity, natural uranium curve (μg/L) Gross beta radioactivity, Cesium-137 curve (pCi/L) Gross beta radioactivity, Strontium-90/ Yttrium-90 curve (pCi/L) Uranium (μg/L) Drinking-water criteria -- -- -- -- -- 15 pCi/L (MCL) 4 mrem/yr (MCL) 4 mrem/yr (MCL) 30 (MCL) Reporting level -- -- 3.0 -- -- 3.0 4.0 4.0 -- Background wells EB-142-A3 --–1.7 (1) --–1.2 (1) --–<3 (1) --–1.3 (1) --–0.99 (1) --–<3 (1) --–5 (1) --–<4 (1) NA --; -- --; -- --; -- --; -- --; -- --; -- --; -- --; -- NA Sedgwick well 1.6–3.4 (4) 1.2–2.2 (4) <0.6–0.9 (4) 1.3–5.3 (4) 0.96–3.5 (4) <3–3.9 (4) 4.1–11 (4) <4–7.9 (4) NA --; -- --; -- --; -- --; -- --; -- --; -- --; -- --; -- NA City well-Sedgwick --–6.1 (1) --–3.1 (1) --–2.7 (1) --–5.6 (1) --–3.3 (1) --–5.2 (1) --–8.2 (1) --–5 (1) NA --; -- --; -- --; -- --; -- --; -- --; -- --; -- --; -- NA TH-02-95 --–4.4 (1) --–2.8 (1) --–2.8 (1) --–3.3 (1) --–1.4 (1) --–4.4 (1) --–5.3 (1) --–2.3 (1) NA --; -- --; -- --; -- --; -- --; -- --; -- --; -- --; -- NA TH-06-95 4.5–5.7 (2) 3.8–4 (2) 4–8.9 (2) 3.4–4.7 (2) 1.3–3.2 (2) 4.8–13 (2) 5.7–9.6 (2) 3.9–4.5 (2) NA --; -- --; -- --; -- --; -- --; -- --; -- --; -- --; -- NA TH-10-95 --–2.4 (1) --–1.3 (1) --–0.7 (1) --–2.5 (1) --–1.6 (1) --–1.3 (1) --–2.3 (1) --–1.5 (1) NA --; -- --; -- --; -- --; -- --; -- --; -- --; -- --; -- NA TH-12-95 --–12 (1) --–6.6 (1) --–19 (1) --–6 (1) --–2.1 (1) --–33 (1) --–19 (1) --–9.2 (1) NA --; -- --; -- --; -- --; -- --; -- --; -- --; -- --; -- NA TH-08-A1 1.9–2.9 (2) 1.5–2.2 (2) <3–<3 (2) 1.1–1.3 (2) 0.76–0.99 (2) <3–<3 (2) <4–<4 (2) <4–<4 (2) NA --; -- --; -- --; -- --; -- --; -- --; -- --; -- --; -- NA TH-08-A2 --–5.8 (1) --–3.7 (1) --–11 (1) --–1.8 (1) --–1.3 (1) --–17 (1) --–8.6 (1) --–6.5 (1) NA --; -- --; -- --; -- --; -- --; -- --; -- --; -- --; -- NA TH-08-A3 NA NA NA NA NA NA NA NA NA NA NA NA NA NA NA NA NA NA TH-08-A4 NA NA NA NA NA NA NA NA NA NA NA NA NA NA NA NA NA NA TH-08-A5 NA NA NA NA NA NA NA NA NA NA NA NA NA NA NA NA NA NA Alta Mills NA NA NA NA NA NA NA NA NA NA NA NA NA NA NA NA NA NA Aquifer storage and recovery prototype wells DW-TW-01 NA --–2.4 (1) 1.2–1.7 (2) --–3.6 (1) NA NA 1.6–4 (2) NA NA NA --; -- --; -- --; -- NA NA --; -- NA NA DW-TW-02 NA --–1.5 (1) 1–1.3 (2) --–1.4 (1) NA NA 2.6–3.4 (2) NA NA NA --; -- --; -- --; -- NA NA --; -- NA NA DW-TW-03 NA --–2.2 (1) 1.5–1.7 (2) --–3.4 (1) NA NA 1.8–3.5 (2) NA NA NA --; -- --; -- --; -- NA NA --; -- NA NA DW-TW-04 NA --–1.6 (1) 1.5–1.5 (2) --–1.4 (1) NA NA 2.2–3.2 (2) NA NA NA --; -- --; -- --; -- NA NA --; -- NA NA DW-TW-05 NA --–1.1 (1) -0.1–0.1 (2) --–1.4 (1) NA NA 2.5–2.8 (2) NA NA

NA --; -- --; -- --; -- NA NA --; -- NA NA

DW-TW-06 NA --–2.2 (1) 0.4–1.7 (2) --–3.4 (1) NA NA 2.4–4.2 (2) NA NA

NA --; -- --; -- --; -- NA NA --; -- NA NA

DW-TW-07 NA --–2.3 (1) 0.9–1.6 (2) --–3.5 (1) NA NA 2.4–2.5 (2) NA NA

NA --; -- --; -- --; -- NA NA --; -- NA NA

DW-TW-08 NA NA --–1.3 (1) NA NA NA --–2.3 (1) NA NA

NA NA --; -- NA NA NA --; -- NA NA

DW-TW-09 NA NA --–1.5 (1) NA NA NA --–3 (1) NA NA

NA NA --; -- NA NA NA --; -- NA NA

RRW-01 NA --–2 (1) 1–1.9 (2) --–3 (1) NA NA 1.6–3.2 (2) NA NA

NA --; -- --; -- --; -- NA NA --; -- NA NA

RRW-02 NA --–1.8 (1) 0.3–0.8 (2) --–1.6 (1) NA NA 3.4–4.2 (2) NA NA

NA --; -- --; -- --; -- NA NA --; -- NA NA

RRW-03 NA --–2.9 (1) --–3.4 (1) --–4 (1) NA NA --–5.4 (1) NA NA

NA --; -- --; -- --; -- NA NA --; -- NA NA
Appendix 13

9

Table A–8. Summary of radionuclide analysis in water samples collected as part of the Equus Beds Groundwater Recharge Project, 1995–2005.—Continued[μg/L, micrograms per liter; pCi/L, picocuries per liter; --, not determined; MCL, Maximum Contaminant Level; mrem/yr, millirem per year; <, less than, NA; not analyzed. The first set of numbers under each heading, for example 99–3,350, indicates the range in concentration. The number in parentheses () indicates the number of samples collected. The numbers below indicate the average followed by the median. Asterisk * is value estimated by using a logprobability regression to predict the values of data below the detection level.]

Data-collection site 

(fig. 6)

Alpha radioactivity 

2-sigma combined 

uncertainty, natural 

uranium curve 

(μg/L)

Alpha radioactivity 

2-sigma combined 

uncertainty, 

Thorium-230 curve 

(pCi/L)

Alpha radioactivity, 

Thorium-230 curve 

(pCi/L)

Beta radioactivity 

2-sigma combined 

uncertainty, 

Cesium-137 curve 

(pCi/L)

Beta radioactivity 

2-sigma combined 

uncertainty, 

Strontium-90/ 

Yttrium-90 curve 

(pCi/L)

Gross alpha 

radioactivity, 

natural uranium 

curve 

(μg/L)

Gross beta 

radioactivity, 

Cesium-137 curve 

(pCi/L)

Gross beta 

radioactivity, 

Strontium-90/ 

Yttrium-90 curve 

(pCi/L)

Uranium

(μg/L)

Drinking-water criteria -- -- -- -- -- 15 pCi/L (MCL) 4 mrem/yr (MCL) 4 mrem/yr (MCL) 30 (MCL)

Reporting level -- -- 3.0 -- -- 3.0 4.0 4.0 --

Shallow index wells

IW-01A NA 0.4–0.56 (2) 0.1–0.2 (2) 0.79–1.1 (2) NA NA 1.1–2.5 (2) NA NA

NA --; -- --; -- --; -- NA NA --; -- NA NA

IW-02A NA 0.54–0.69 (2) 0.5–0.6 (2) 0.91–1.1 (2) NA NA 2.5–3 (2) NA NA

NA --; -- --; -- --; -- NA NA --; -- NA NA

IW-03A NA --–3.1 (1) --–1 (1) --–1.6 (1) NA NA --–1.4 (1) NA NA

NA --; -- --; -- --; -- NA NA --; -- NA NA

IW-04A NA --–3 (1) --–1 (1) --–2.7 (1) NA NA --–10.9 (1) NA NA

NA --; -- --; -- --; -- NA NA --; -- NA NA

IW-05A NA --–1.9 (1) --–1.2 (1) --–1.3 (1) NA NA --–4 (1) NA NA

NA --; -- --; -- --; -- NA NA --; -- NA NA

IW-06A NA 2.7–3.1 (2) -0.3–0.8 (2) 2.1–2.1 (2) NA NA 2.1–3.2 (2) NA --–0.16 (1)

NA --; -- --; -- --; -- NA NA --; -- NA --; --

IW-07A NA --–2 (1) --–0.7 (1) --–1.4 (1) NA NA --–2.2 (1) NA NA

NA --; -- --; -- --; -- NA NA --; -- NA NA

IW-08A NA 8.2–9.5 (2) 8.2–12.6 (2) 4.5–5.3 (2) NA NA 8.3–10.6 (2) NA NA

NA --; -- --; -- --; -- NA NA --; -- NA NA

IW-09A NA 2.9–3.3 (2) 2.4–2.4 (2) 2.3–2.5 (2) NA NA 6.1–6.4 (2) NA NA

NA --; -- --; -- --; -- NA NA --; -- NA NA

IW-10A NA --–2.3 (1) --–0.5 (1) --–1.6 (1) NA NA --–4.4 (1) NA NA

NA --; -- --; -- --; -- NA NA --; -- NA NA

IW-11A-2 NA --–1.9 (1) -0.1–1 (2) --–1.3 (1) NA NA 2–3 (2) NA NA

NA --; -- --; -- --; -- NA NA --; -- NA NA

IW-12A NA 2–4.1 (2) 1.4–3.7 (2) 1.7–2.1 (2) NA NA 2–4.3 (2) NA --–3.88 (1)

NA --; -- --; -- --; -- NA NA --; -- NA --; --

IW-13A NA --–5.2 (1) 1.4–1.5 (2) --–4.4 (1) NA NA 7.1–7.7 (2) NA --–0.15 (1)

NA --; -- --; -- --; -- NA NA --; -- NA --; --

IW-14A NA --–5 (1) 1.6–3.6 (2) --–3.1 (1) NA NA 4.3–6.2 (2) NA NA

NA --; -- --; -- --; -- NA NA --; -- NA NA

IW-15A NA --–6.7 (1) --–6.1 (1) --–4.2 (1) NA NA --–6.1 (1) NA NA

NA --; -- --; -- --; -- NA NA --; -- NA NA

IW-16A NA --–4.8 (1) 3.2–4.7 (2) --–2.7 (1) NA NA 4.9–7 (2) NA NA

NA --; -- --; -- --; -- NA NA --; -- NA NA

IW-17A NA --–4.2 (1) --–3.7 (1) --–2.9 (1) NA NA --–5.8 (1) NA NA

NA --; -- --; -- --; -- NA NA --; -- NA NA

IW-18A NA --–13 (1) 12.7–43.7 (2) --–5.5 (1) NA NA 19–44.1 (2) NA NA

NA --; -- --; -- --; -- NA NA --; -- NA NA

IW-19A NA --–8.5 (1) --–8.5 (1) --–5.5 (1) NA NA --–7.8 (1) NA NA

NA --; -- --; -- --; -- NA NA --; -- NA NA

IW-20A NA 6.6–6.8 (2) 3.9–4.4 (2) 5.1–5.4 (2) NA NA 7–7.6 (2) NA NA

NA --; -- --; -- --; -- NA NA --; -- NA NA

IW-21A NA --–5.3 (1) 4.3–4.5 (2) --–3.2 (1) NA NA 5.2–7.6 (2) NA NA

NA --; -- --; -- --; -- NA NA --; -- NA NA

IW-22A NA 3.2–4.7 (2) 1.3–6.1 (2) 3–3.1 (2) NA NA 7.9–9.8 (2) NA --–2.94 (1)

NA --; -- --; -- --; -- NA NA --; -- NA --; --

IW-23A NA --–4.3 (1) --–2.5 (1) --–2 (1) NA NA --–2 (1) NA NA

NA --; -- --; -- --; -- NA NA --; -- NA NA

IW-24A NA --–3.4 (1) --–2.4 (1) --–3.8 (1) NA NA --–8.5 (1) NA --–5.7 (1)

NA --; -- --; -- --; -- NA NA --; -- NA --; --

IW-25A NA 5.1–5.2 (2) 9.8–11.4 (2) 4.1–4.2 (2) NA NA 13.9–15.8 (2) NA NA

NA --; -- --; -- --; -- NA NA --; -- NA NA

IW-26A NA --–5.5 (1) --–9.4 (1) --–2.6 (1) NA NA --–13.5 (1) NA NA

NA --; -- --; -- --; -- NA NA --; -- NA NA
140 Water Quality in the Equus Beds Aquifer and the Little Arkansas River, South-Central Kansas Table A–8. Summary of radionuclide analysis in water samples collected as part of the Equus Beds Groundwater Recharge Project, 1995–2005.—Continued [μg/L, micrograms per liter; pCi/L, picocuries per liter; --, not determined; MCL, Maximum Contaminant Level; mrem/yr, millirem per year; <, less than, NA; not analyzed. The first set of numbers under each heading, for example 99–3,350, indicates the range in concentration. The number in parentheses () indicates the number of samples collected. The numbers below indicate the average followed by the median. Asterisk * is value estimated by using a log- probability regression to predict the values of data below the detection level.] Data-collection site (fig. 6) Alpha radioactivity 2-sigma combined uncertainty, natural uranium curve (μg/L) Alpha radioactivity 2-sigma combined uncertainty, Thorium-230 curve (pCi/L) Alpha radioactivity, Thorium-230 curve (pCi/L) Beta radioactivity 2-sigma combined uncertainty, Cesium-137 curve (pCi/L) Beta radioactivity 2-sigma combined uncertainty, Strontium-90/ Yttrium-90 curve (pCi/L) Gross alpha radioactivity, natural uranium curve (μg/L) Gross beta radioactivity, Cesium-137 curve (pCi/L) Gross beta radioactivity, Strontium-90/ Yttrium-90 curve (pCi/L) Uranium (μg/L) Drinking-water criteria -- -- -- -- -- 15 pCi/L (MCL) 4 mrem/yr (MCL) 4 mrem/yr (MCL) 30 (MCL) Reporting level -- -- 3.0 -- -- 3.0 4.0 4.0 -- Shallow index wells—Continued IW-27A NA --–4.6 (1) --–8 (1) --–3.8 (1) NA NA --–9.5 (1) NA NA NA --; -- --; -- --; -- NA NA --; -- NA NA IW-28A NA 4.2–5.3 (2) 6.8–9.6 (3) 3.7–4 (2) NA NA 6.9–7.6 (3) NA NA NA --; -- --; -- --; -- NA NA --; -- NA NA IW-29A NA --–5.6 (1) --–4.2 (1) --–3.7 (1) NA NA --–4.6 (1) NA 1.26–1.59 (2) NA --; -- --; -- --; -- NA NA --; -- NA --; -- IW-30A NA --–5.7 (1) --–4.8 (1) --–3.7 (1) NA NA --–9.9 (1) NA 2.22–2.34 (2) NA --; -- --; -- --; -- NA NA --; -- NA --; -- IW-31A NA --–5.3 (1) --–3.8 (1) --–3.7 (1) NA NA --–6.9 (1) NA NA NA --; -- --; -- --; -- NA NA --; -- NA NA IW-32A NA 4.2–5.3 (3) 13.6–20 (4) 2.1–3.7 (3) NA NA 6–19.4 (4) NA NA NA --; -- --; -- --; -- NA NA --; -- NA NA IW-33A NA --–2.6 (1) --–2.4 (1) --–3.6 (1) NA NA --–6 (1) NA NA NA --; -- --; -- --; -- NA NA --; -- NA NA IW-34A NA --–3.4 (1) 3.2–5.2 (2) --–2.1 (1) NA NA 3.9–6 (2) NA NA NA --; -- --; -- --; -- NA NA --; -- NA NA IW-35A NA --–8.3 (1) 6.3–8.9 (2) --–11 (1) NA NA 10–13.1 (2) NA 5.51–7.45 (2) NA --; -- --; -- --; -- NA NA --; -- NA --; -- IW-36A NA --–8.7 (1) --–5.6 (1) --–6.9 (1) NA NA --–5.7 (1) NA 1.69–1.91 (2) NA --; -- --; -- --; -- NA NA --; -- NA --; -- IW-37A NA --–4.7 (1) --–2.2 (1) --–3.6 (1) NA NA --–5.9 (1) NA NA NA --; -- --; -- --; -- NA NA --; -- NA NA IW-38A NA 3.8–5.1 (2) 2–2.6 (2) 3.5–4.1 (2) NA NA 8.7–9.8 (2) NA NA NA --; -- --; -- --; -- NA NA --; -- NA NA Deep index wells IW-01C NA 1.6–5 (2) -0.4–2.1 (2) 1.6–3.5 (2) NA NA 1.7–3.9 (2) NA NA NA --; -- --; -- --; -- NA NA --; -- NA NA IW-02C NA 1.2–1.5 (2) 0.8–1 (2) 1.1–1.3 (2) NA NA 2.5–3 (2) NA NA NA --; -- --; -- --; -- NA NA --; -- NA NA IW-03C NA --–1.7 (1) --–-0.5 (1) --–1.1 (1) NA NA --–2.8 (1) NA --–0.21 (1) NA --; -- --; -- --; -- NA NA --; -- NA --; -- IW-04C NA --–4.2 (1) --–2.2 (1) --–2.9 (1) NA NA --–6 (1) NA NA NA --; -- --; -- --; -- NA NA --; -- NA NA IW-05C NA --–2.5 (1) --–0.8 (1) --–2 (1) NA NA --–5 (1) NA NA NA --; -- --; -- --; -- NA NA --; -- NA NA IW-06C NA 1.7–2 (2) 0.7–1.2 (2) 1.4–2 (2) NA NA 2.6–3.9 (2) NA NA NA --; -- --; -- --; -- NA NA --; -- NA NA IW-07C NA --–2.3 (1) --–1.2 (1) --–1.6 (1) NA NA --–3.4 (1) NA NA

NA --; -- --; -- --; -- NA NA --; -- NA NA

IW-08C NA 7.3–19 (2) 2.2–9.6 (2) 5.3–14 (2) NA NA 10.3–16.8 (2) NA 0.12–0.15 (3)

NA --; -- --; -- --; -- NA NA --; -- NA --; --

IW-09C NA 2–3.3 (2) 0.2–2.4 (2) 1.9–2 (2) NA NA 2.2–4.4 (2) NA NA

NA --; -- --; -- --; -- NA NA --; -- NA NA

IW-10C NA --–1.4 (1) --–0.3 (1) --–1.3 (1) NA NA --–4 (1) NA NA

NA --; -- --; -- --; -- NA NA --; -- NA NA

IW-11C NA --–2.2 (1) 0.4–0.5 (2) --–1.3 (1) NA NA 1.5–2.8 (2) NA NA

NA --; -- --; -- --; -- NA NA --; -- NA NA

IW-12C NA 4.8–6.5 (2) -1.9–0.5 (2) 4–4 (2) NA NA 3.3–3.8 (2) NA NA

NA --; -- --; -- --; -- NA NA --; -- NA NA

IW-13C NA --–2.1 (1) 0.8–1.7 (2) --–1.3 (1) NA NA 3–3.1 (2) NA NA

NA --; -- --; -- --; -- NA NA --; -- NA NA

IW-14C NA --–7.5 (1) 2.5–3.8 (2) --–4.8 (1) NA NA 5.1–6 (2) NA NA

NA --; -- --; -- --; -- NA NA --; -- NA NA

IW-15C NA --–5.2 (1) --–3.8 (1) --–3.2 (1) NA NA --–5.7 (1) NA NA

NA --; -- --; -- --; -- NA NA --; -- NA NA
Appendix 14

1

Table A–8. Summary of radionuclide analysis in water samples collected as part of the Equus Beds Groundwater Recharge Project, 1995–2005.—Continued[μg/L, micrograms per liter; pCi/L, picocuries per liter; --, not determined; MCL, Maximum Contaminant Level; mrem/yr, millirem per year; <, less than, NA; not analyzed. The first set of numbers under each heading, for example 99–3,350, indicates the range in concentration. The number in parentheses () indicates the number of samples collected. The numbers below indicate the average followed by the median. Asterisk * is value estimated by using a logprobability regression to predict the values of data below the detection level.]

Data-collection site 

(fig. 6)

Alpha radioactivity 

2-sigma combined 

uncertainty, natural 

uranium curve 

(μg/L)

Alpha radioactivity 

2-sigma combined 

uncertainty, 

Thorium-230 curve 

(pCi/L)

Alpha radioactivity, 

Thorium-230 curve 

(pCi/L)

Beta radioactivity 

2-sigma combined 

uncertainty, 

Cesium-137 curve 

(pCi/L)

Beta radioactivity 

2-sigma combined 

uncertainty, 

Strontium-90/ 

Yttrium-90 curve 

(pCi/L)

Gross alpha 

radioactivity, 

natural uranium 

curve 

(μg/L)

Gross beta 

radioactivity, 

Cesium-137 curve 

(pCi/L)

Gross beta 

radioactivity, 

Strontium-90/ 

Yttrium-90 curve 

(pCi/L)

Uranium

(μg/L)

Drinking-water criteria -- -- -- -- -- 15 pCi/L (MCL) 4 mrem/yr (MCL) 4 mrem/yr (MCL) 30 (MCL)Reporting level -- -- 3.0 -- -- 3.0 4.0 4.0 --

Deep index wells—Continued

IW-16C NA --–3.4 (1) -0.8–0.9 (2) --–2.8 (1) NA NA 4.2–6.8 (2) NA NA

NA --; -- --; -- --; -- NA NA --; -- NA NA

IW-17C NA 1.5–2.2 (2) -0.6–1.5 (2) 1.7–1.8 (2) NA NA 3.8–4.9 (2) NA NA

NA --; -- --; -- --; -- NA NA --; -- NA NA

IW-18C NA --–6.1 (1) --–2 (1) --–3 (1) NA NA --–4.3 (1) NA NA

NA --; -- --; -- --; -- NA NA --; -- NA NA

IW-19C NA --–5.7 (1) --–5.7 (1) --–3.4 (1) NA NA --–4.7 (1) NA NA

NA --; -- --; -- --; -- NA NA --; -- NA NA

IW-20C NA 5.8–6 (2) 5.2–5.7 (2) 3.5–4.2 (2) NA NA 6.5–10.7 (2) NA 0.28–0.31 (2)

NA --; -- --; -- --; -- NA NA --; -- NA --; --

IW-21C NA --–7.3 (1) 2.6–3.1 (2) --–5.5 (1) NA NA 6.7–7.9 (2) NA NA

NA --; -- --; -- --; -- NA NA --; -- NA NA

IW-22C NA 2.1–2.5 (2) -0.4–0.3 (2) 2.3–2.3 (2) NA NA 4–5.5 (2) NA NA

NA --; -- --; -- --; -- NA NA --; -- NA NA

IW-23C NA --–3.9 (1) --–0.2 (1) --–2.1 (1) NA NA --–3.1 (1) NA NA

NA --; -- --; -- --; -- NA NA --; -- NA NA

IW-24C NA --–5.2 (1) --–5.1 (1) --–4.7 (1) NA NA --–5.1 (1) NA --–5.15 (1)

NA --; -- --; -- --; -- NA NA --; -- NA --; --

IW-25C NA 4.8–5.2 (2) 8–9.1 (2) 4.1–4.1 (2) NA NA 9–9.1 (2) NA 3.94–3.97 (2)

NA --; -- --; -- --; -- NA NA --; -- NA --; --

IW-26C NA --–6.1 (1) --–2.6 (1) --–3 (1) NA NA --–7.5 (1) NA NA

NA --; -- --; -- --; -- NA NA --; -- NA NA

IW-27C NA --–3.1 (1) --–1.6 (1) --–3.4 (1) NA NA --–3.8 (1) NA NA

NA --; -- --; -- --; -- NA NA --; -- NA NA

IW-28C NA --–3.7 (1) 3.6–3.7 (2) --–3.6 (1) NA NA 4.5–6.5 (2) NA NA

NA --; -- --; -- --; -- NA NA --; -- NA NA

IW-29C NA --–3.4 (1) --–0.5 (1) --–3.9 (1) NA NA --–3.9 (1) NA NA

NA --; -- --; -- --; -- NA NA --; -- NA NA

IW-30C NA --–7.2 (1) --–8.8 (1) --–6.2 (1) NA NA --–8.6 (1) NA 4.66–5.54 (3)

NA --; -- --; -- --; -- NA NA --; -- NA --; --

IW-31C NA --–5.4 (1) --–5.4 (1) --–3.9 (1) NA NA --–10.5 (1) NA --–3.27 (1)

NA --; -- --; -- --; -- NA NA --; -- NA --; --

IW-32C NA --–3.9 (1) 2.8–4.3 (2) --–3 (1) NA NA 4.8–6.3 (2) NA NA

NA --; -- --; -- --; -- NA NA --; -- NA NA

IW-33C NA --–3.3 (1) --–2.1 (1) --–4.7 (1) NA NA --–5.2 (1) NA NA

NA --; -- --; -- --; -- NA NA --; -- NA NA

IW-34C NA --–4.7 (1) 5.8–7.1 (2) --–2.6 (1) NA NA 5.5–7.6 (2) NA NA

NA --; -- --; -- --; -- NA NA --; -- NA NA

IW-35C NA --–5.3 (1) 4.9–5.2 (2) --–7 (1) NA NA 7.1–7.5 (2) NA 5–5.34 (2)

NA --; -- --; -- --; -- NA NA --; -- NA --; --

IW-36C NA --–5.4 (1) --–1.9 (1) --–4.7 (1) NA NA --–8.9 (1) NA NA

NA --; -- --; -- --; -- NA NA --; -- NA NA

IW-37C NA --–3.6 (1) --–2.6 (1) --–3.1 (1) NA NA --–6.1 (1) NA NA

NA --; -- --; -- --; -- NA NA --; -- NA NA

IW-38C NA 4–4.5 (2) 4.6–7.2 (2) 2.4–3.1 (2) NA NA 6.2–7.4 (2) NA NA

NA --; -- --; -- --; -- NA NA --; -- NA NA
142 Water Quality in the Equus Beds Aquifer and the Little Arkansas River, South-Central Kansas

0

*Chromium

Bromide

*Nickel

Turbidity laboratory

*Zinc

*Lead

Ammonia

*Total organic carbon

Phosphorus

Orthophosphate

Fecal coliform bacteria

Iron

*Boron

*Selenium

Triazine herbicide screen

5 10 15 20 25 30 35 35

WATER-QUALITY CONSTITUENT

PERCENT

Concentrations near the reporting level *

Figure A-1. Relative percentage difference (RPDs) for replicate sample collected during 1995–2004 that exceeded 10 percent. All 

other constituents had less than 10-percent difference.
Appendix 143

SODIUM

ALKALINITY, as CaCO3

PERCENT

0 2 4 6 8 10 12

FLUORIDE

WATER-QUALITY CONSTITUENT

DISSOLVED SOLIDS

ORGANIC CARBON

SPECIFIC CONDUCTANCE

FLUORIDE

DISSOLVED SOLIDS

SODIUM

ORTHOPHOSPHATE

NITRITE PLUS NITRATE

SULFATE

ALKALINITY

PERCENT

0 2 4 6 8 10 12 14 16

WATER-QUALITY CONSTITUENT

Figure A-2. Detection frequency of various water-quality constituents in blank samples collected during 

1995–2004 from sites in study area used for this report. All other constituents detected in less than 1 

percent of blank samples.

Figure A-3. Detection frequency of various water-quality constituents in blank samples collected during 

1999–2004 from sites in study area used for this report. All other constituents detected in less than1 percent 

of blank samples.
144 Water Quality in the Equus Beds Aquifer and the Little Arkansas River, South-Central Kansas

Publishing support provided by: 

Rolla Publishing Service Center

For additional information concerning this publication, contact:

Director, USGS Kansas Water Science Center 

4821 Quail Crest Place

Lawrence, KS 66049

(785) 842–9909

Or visit the Kansas Water Science Center Web site at:

http://ks.water.usgs.gov

Ziegler and others—Water Quality in the Equus Beds Aquifer and the Little Arkansas River Before Implementation of Large-Scale Artificial Recharge—SIR 2010–5023