U.S. Department of the Interior

U.S. Geological Survey

U.S. Geological Survey Toxic Substances Hydrology Program

Open-File Report 2006–1207

Results of Analyses of the Fungicide 

Chlorothalonil, Its Degradation Products, and 

Other Selected Pesticides at 22 Surface-Water 

Sites in Five Southern States, 2003–04

MEXICO

Texas

Oklahoma

Kansas Missouri

Arkansas

Louisiana

Mississippi

Tennessee

Kentucky

Indiana Illinois

West

Virginia

Virginia

North

Carolina

South

Carolina

Georgia

Alabama

Florida

Gulf of Mexico

Atlantic

Ocean

18

20

19

21

7

9

13 12

14 10 17

11

15 16 2

8 3

6

5 1

4

22

Results of Analyses of the Fungicide 

Chlorothalonil, Its Degradation Products, 

and Other Selected Pesticides at 22 SurfaceWater Sites in Five Southern States, 

2003–04

By Elisabeth A. Scribner, James L. Orlando, William A. Battaglin, 

Mark W. Sandstrom, Kathryn M. Kuivila, and Michael T. Meyer

U.S. Geological Survey Toxic Substances Hydrology Program

Open-File Report 2006–1207

U.S. Department of the Interior

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

DIRK KEMPTHORNE, Secretary

U.S. Geological Survey

P. Patrick Leahy, Acting Director

U.S. Geological Survey, Reston, Virginia: 2006

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U.S. Government.

Although this report is in the public domain, permission must be secured from the individual copyright owners to 

reproduce any copyrighted materials contained within this report.

Suggested citation:

Scribner, E.A., Orlando, J.L., Battaglin, W.A., Sandstrom, M.W., Kuivila, K.M., and Meyer, M.T., 2006, Results of 

analyses of the fungicide chlorothalonil, its degradation products, and other selected pesticides at 22 surface-water 

sites in five Southern States, 2003–04: U.S. Geological Survey Open-File Report 2006–1207, 59 p.

Back cover:

Spraying of chlorothalonil on a peanut field in the Southern United States.
iii

Contents

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

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

Background.............................................................................................................................................. 1

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

Acknowledgments.................................................................................................................................. 4

Sampling Methods and Procedures............................................................................................................. 4

Sampling-Site Selection Method ......................................................................................................... 4

Sample Collection................................................................................................................................... 5

Sample Processing................................................................................................................................. 7

Analytical Methods and Procedures............................................................................................................ 8

Analysis of Chlorothalonil and Its Degradation Products by Liquid Chromatography/

Mass Spectrometry .................................................................................................................. 8

Materials ......................................................................................................................................... 8

Atmospheric Pressure Chemical Ionization Method Used in 2003 ....................................... 8

Atmospheric Pressure Chemical Ionization and Electrospray Ionization Methods Used 

in 2004................................................................................................................................. 10

Identification and Quantification................................................................................................. 10

Analysis of Chlorothalonil by Gas Chromatography/Mass Spectrometry..................................... 10

Solid-Phase Extraction ................................................................................................................. 10

Gas Chromatography/Mass Spectrometry................................................................................ 13

Analysis of Other Selected Pesticides and Their Degradation Products ..................................... 13

Determination of Dissolved Organic Carbon...................................................................................... 13

Analysis of Suspended Sediment ........................................................................................................ 13

Quality Assurance............................................................................................................................................ 13

Analysis of Chlorothalonil and Its Degradation Products by Liquid Chromatography/

Mass Spectrometry .................................................................................................................. 13

Analysis of Chlorothalonil by Gas Chromatography/Mass Spectrometry..................................... 18

Analysis of Other Pesticides and Their Degradation Products ...................................................... 18

Results of Analyses ......................................................................................................................................... 18

Chlorothalonil and Its Degradation Products..................................................................................... 19

Other Selected Pesticides and Their Degradation Products .......................................................... 20

Dissolved Organic Carbon and Suspended Sediment...................................................................... 20

Associated Streamflow and Physical Properties.............................................................................. 22

Conclusions....................................................................................................................................................... 22

References Cited.............................................................................................................................................. 23

Supplemental Information.............................................................................................................................. 27
iv

Figures

1. Map showing location of 22 surface-water sampling sites in five Southern States, 

2003–04 ............................................................................................................................................. 2

2. Map showing geographic distribution of chlorothalonil applications at 22 surface-water 

sampling sites in five Southern States........................................................................................ 4

3. Chemical structures of chlorothalonil and five degradation products .................................... 5

Tables

1. Site name, location, year sampled, watershed basin size, and amount of chlorothalonil 

application during 1997 in counties adjacent to 22 surface-water sampling sites in five 

Southern States, 2003–04 .............................................................................................................. 6

2. Type of analysis, number of bottles, sample volume, and year collected for surfacewater samples collected from five Southern States, 2003–04 ................................................ 8

3. Operating conditions of liquid chromatograph/mass spectrometer using atmospheric 

pressure chemical ionization and electrospray ionization for analysis of samples from 

22 surface-water sampling sites in five Southern States, 2003–04........................................ 9

4. Compounds analyzed in samples from 22 surface-water sampling sites in five Southern 

States using U.S. Geological Survey National Water-Quality Laboratory schedules 2001 

and 2060, 2003–04 ........................................................................................................................... 11

5. Concentrations of chlorothalonil and three chlorothalonil degradation products in 

quality-assurance samples from surface-water sampling sites in five Southern States 

as determined by U.S. Geological Survey Organic Geochemistry Research Laboratory,

2003–04 ............................................................................................................................................. 14

6. Percentage recoveries of chlorothalonil in extracts of reagent-water samples fortified 

at 0.025 microgram per liter, extracted by solid-phase extraction in July–August 2003, 

and analyzed by gas chromatography/mass spectrometry in March 2004 .......................... 19

7. Percentage recoveries of surrogate compounds in samples from 22 surface-water 

sampling sites in five Southern States using U.S. Geological Survey National WaterQuality Laboratory schedules 2001 and 2060, 2003–04............................................................. 19

8. Statistical summary of concentrations of chlorothalonil and three chlorothalonil 

degradation products determined by liquid chromatography/mass spectrometry and 

gas chromatography/mass spectrometry for water samples collected from 22 sampling 

sites in five Southern States, 2003–04......................................................................................... 20

9. Statistical summary of concentrations of selected pesticides and pesticide degradation 

products determined by U.S. Geological Survey National Water-Quality Laboratory 

schedules 2001 and 2060 for water samples collected from 22 surface-water sampling 

sites in five Southern States, 2003–04......................................................................................... 21

10. Statistical summary of concentrations of dissolved organic carbon, suspended 

sediment, and percentage of silt- and clay-sized particles for water samples collected 

from 22 surface-water sampling sites in five Southern States, 2003–04............................... 23

11. Statistical summary of streamflow and physical properties determined for water 

samples collected from 22 surface-water sampling sites in five Southern States, 

2003–04 ............................................................................................................................................. 23

12. Concentrations of chlorothalonil and three chlorothalonil degradation products analyzed 

by the U.S. Geological Survey Organic Geochemistry Research Laboratory for water 

samples collected from 22 surface-water sampling sites in five Southern States, 2003–04 28
13. Concentrations of chlorothalonil analyzed by the U.S. Geological Survey Methods and 

Research Development Group for water samples collected from 22 surface-water 

sampling sites in five Southern States, July through September 2003.................................. 33

14. Concentrations of selected pesticides and pesticide degradation products analyzed 

by the U.S. Geological Survey National Water-Quality Laboratory schedule 2001 for 

water samples collected from 22 surface-water sampling sites in five Southern States, 

2003–04 ............................................................................................................................................. 36

15. Concentrations of selected pesticides and pesticide degradation products analyzed by 

the U.S. Geological Survey National Water-Quality Laboratory schedule 2060 for water 

samples collected from 22 surface-water sampling sites in five Southern States, 

2003–04 ............................................................................................................................................. 47

16. Concentrations of dissolved organic carbon, suspended sediment, and percentage of 

silt- and clay-sized particles for water samples collected from 22 surface-water sampling 

sites in five Southern States, 2003–04......................................................................................... 52

17. Results of analysis of streamflow, gage height, and physical properties for water

samples collected from 22 surface-water sampling sites in five Southern States, 

2003–04 ............................................................................................................................................. 56

Conversion Factors, Abbreviated Water-Quality Units, and Datum 

 Multiply By To obtain

acre 4,047 square meter (m2)

cubic centimeter (cm3) 0.6102 cubic inch (in3)

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

foot (ft) 0.3048 meter (m)

liter (L) 0.2642 gallon (gal)

microgram (μg) 3.527 x 10-8 ounce (oz)

microliter (μL) 2.642 x 10-7 gallon (gal)

micrometer (μm) 3.937 x 10-5 inch (in.)

mile (mi) 1.609 kilometer (km)

milligram (mg) 3.53 x 10-5 ounce (oz)

milliliter (mL) 0.0338 ounce (oz)

millimeter (mm) 0.03937 inch (in.)

nanogram (ng) 3.527 x 10-11 ounce (oz)

ounce, fluid (oz) 0.02957 liter (L)

pound (lb) 453.6 gram (g)

pound per square inch (lb/in2) 0.07031 kilogram per square centimeter (kg/cm2)

square mile (mi2) 2.590 square kilometer (km2)

Temperature can be converted to degrees Celsius ( ̊C) or degrees Fahrenheit ( ̊F) by the equations:

 ̊C = 5/9 ( ̊F -32)

 ̊F = 9/5 ( ̊C) +32.
vi

Abbreviated Water-Quality Units

microgram per liter (μg/L)

microgram per milliliter (μg/mL)

microsiemens per centimeter at 25 degrees Celsius (μS/cm)

milligram per liter (mg/L)

milliliter (mL)

milliliter per minute (mL/min)

Datum

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

In accordance with the mission of the U.S. Geological Survey (USGS) Toxic Substances Hydrology Program, a 

pesticide study was conducted during 2003–04 to determine 

the occurrence of the fungicide chlorothalonil and its degradation products at 22 surface-water sites in five Southern States. 

Water-quality samples were collected during the peanut-growing season (June–September) in 2003. During the peanutgrowing season in 2004, samples were collected after large 

storms.

An analytical method was developed at the USGS 

Organic Geochemistry Research Laboratory in Lawrence, 

Kansas, to measure chlorothalonil and its degradation products 

by liquid chromatography/mass spectrometry (LC/MS). Chlorothalonil was detected in 4 of the 113 surface-water samples. 

The primary degradation product of chlorothalonil, 4-hydroxychlorothalonil, was detected in 26 of the 113 samples with 

concentrations ranging from 0.002 to 0.930 microgram per 

liter. The chlorothalonil degradation products, 1-amide-4-

hydroxy-chorothalonil and 1,3-diamide-chlorothalonil, were 

detected in one water sample each at 0.020 and 0.161 microgram per liter, respectively.

The USGS Methods and Research Development Group, 

Lakewood, Colorado, developed a custom method for chlorothalonil using gas chromatography/mass spectrometry 

(GC/MS) in an effort to achieve a lower laboratory reporting 

level (LRL) than the USGS National Water-Quality Laboratory (NWQL) schedule 2060, which analyzes the compound 

chlorothalonil at a LRL of 0.035 μg/L. The group succeeded 

in achieving a lower GC/MS reporting level of 0.01 μg/L. 

Chlorothalonil was detected in 5 of 68 water samples analyzed 

using the custom GC/MS method, whereas chlorothalonil 

was detected in 2 of 21 water samples analyzed using NWQL 

schedule 2060.

 In addition to analysis of chlorothalonil and its degradation products, samples were analyzed using the USGS NWQL 

schedules 2001 and 2060 for about 114 pesticides and their 

degradation products. Samples also were analyzed for dissolved organic carbon, suspended sediment, and percentage of 

silt- and clay-sized particles.

Overall, it was found that chlorothalonil was detected 

only infrequently and at relatively low concentrations. 

Chlorothalonil’s major degradation product, 4-hydroxychlorothalonil, was detected most frequently, occurred generally at higher concentrations in water samples than did the 

parent fungicide, and the data from this study reaffirmed that 

it is the dominant degradation product of chlorothalonil in the 

peanut-growing environment.

Introduction

Background

The primary objective of Pesticide Studies (PEST) in the 

U.S. Geological Survey’s (USGS) Toxic Substances Hydrology Program is to conduct research on the occurrence, fate, 

and ecotoxicity of new or understudied pesticides and pesticide degradation products in the environment. In line with this 

objective, PEST conducted a study during 2003–04 to improve 

understanding of these processes with regard to the extensively 

used fungicide, chlorothalonil, and its degradation products. 

Chlorothalonil has a wide variety of beneficial uses, including 

agricultural, home and garden, industrial, and vector control of 

fungi, and it is used extensively for disease control in peanuts, 

potatoes, turf, and many fruit and vegetable crops (Cox, 1997). 

However, the transport of chlorothalonil and its degradation 

products through natural and human processes from the point 

of application could result in potentially harmful concentrations in the environment. During the study, water samples 

were collected from 22 surface-water sampling sites in five 

Southern States—Alabama, Florida, Georgia, Oklahoma, and 

Texas (fig. 1).

Results of Analyses of the Fungicide Chlorothalonil, Its 

Degradation Products, and Other Selected Pesticides at 

22 Surface-Water Sites in Five Southern States, 2003–04

By Elisabeth A. Scribner, James L. Orlando, William A. Battaglin, Mark W. Sandstrom, Kathryn M. Kuivila, and 

Michael T. Meyer
Figure 1. Location of 22 surface-water sampling sites in five Southern States, 2003–04.

   Results of Analyses of the Fungicide Chlorothalonil, Its Degradation Products, and Other Selected Pesticides

102° 39°

36°

33°

30°

27°

99° 96° 93° 90° 87° 84° 81°

0 75 150 225 300 MILES

0

Base from U.S. Geological Survey digital data, 1:2,000,000, 1994 

Albers Equal-Area Conic projection

Standard parallels 29°30’ and 45°30’, central meridian -96°

Horizontal coordinate information is referenced to the North American

 Datum of 1983 (NAD 83)

75 150 225 300 KILOMETERS

MEXICO

Texas

Oklahoma

Kansas

Missouri

Arkansas

Louisiana

Mississippi

Tennessee

Kentucky

Indiana Illinois

West

Virginia

Virginia

North

Carolina

South

Carolina

Georgia

Alabama

Florida

Gulf of Mexico

Atlantic

Ocean

EXPLANATION

2003 sampling site and

 map number

2003 and 2004 sampling site and map number

18

20

19

21

7

7

9

13 12

14 10 17

11

15 16

2

3 8 6

5 1

4

22

22

Index map

MEXICO

CANADA

UNITED STATES
Chlorothalonil (1,3-dicyano-2,4,5,6-tetrachlorobenzene) 

is a broad spectrum, non-systemic fungicide used as a preventative treatment to control foliar diseases of vegetable, field, 

and ornamental crops. It was first registered for use on food 

crops in the United States in 1970 by the U.S. Environmental 

Protection Agency. Chlorothalonil frequently is applied multiple times per growing season and can be used exclusively or 

in rotation with other fungicides. Chlorothalonil is one of the 

most extensively used fungicides in the United States. During 1992, it was the second-most extensively used fungicide 

behind only sulfur, and in 1997 ranked third behind sulfur and 

copper. Pesticide use data show that chlorothalonil applications nationwide exceeded 10 million lb annually during both 

1992 and 1997 (National Center for Food and Agricultural 

Policy, 1997). Chlorothalonil application data by county for 

1997 show that areas of highest use occurred in Alabama, 

Florida, and Georgia, with less amounts in Oklahoma and 

Texas (fig. 2). Peanuts are the primary crops treated with 

chlorothalonil in these five States.

Chlorothalonil has the potential to be transported away 

from the point of application either through spray drift, field 

runoff, or on sediment mobilized by runoff (Cox, 1997). The 

field half-life for chlorothalonil ranges from 10 to 60 days 

(Syngenta Crop Protection, 2005), and this coupled with large 

application amounts and the practice of frequent, repeated 

applications would tend to promote the offsite movement of 

this fungicide. It has been detected in surface water (Scott and 

others, 2002), rainfall (Sakai, 2002), and chlorothalonil degradation products have been detected in ground-water samples 

(Harris and Andreoli, 1988). Chlorothalonil also has been 

detected in air samples at great distances from areas where it 

is applied, such as the Bering Sea (Chernyak and others, 1996) 

and Sequoia National Park, California (McConnell and others, 

1998). The U.S. Environmental Protection Agency (1999) has 

classified chlorothalonil as a probable carcinogen because tests 

have shown very high toxicity to both terrestrial and aquatic 

vertebrates (Cox, 1997).

Chlorothalonil has three principle degradation products, 4-hydroxy-chlorothalonil (1,3-dicyano-4-hydroxy2,5,6-trichlorobenzene), 1,3-diamide-chlorothalonil 

(1,3-dicarbamoyl-2,4,5,6-tetrachlorobenzene), and 1-amide4-hydroxy-chlorothalonil (1-carbamoyl-3-cyano-4-hydroxy2,5,6-trichlorobenzene) (Sato and Tanaka, 1987; Rouchaud 

and others, 1988; Katayama and others, 1992). Two additional degradation products have been tentatively identified, 

1-amide-2-hydroxy-chlorothalonil (1-carbamoyl-2-hydroxy5-cyano-3,4,6-trichlorobenzene) and 4-hydroxy-1,3-diamidechlorothalonil (1,3-dicarbamoyl-2,4,5-trichloro-6-hydroxybenzene) (fig. 3).

Research was undertaken by the USGS Organic Geochemistry Research Laboratory (OGRL), Lawrence, Kansas, 

to develop a reliable, sensitive analytical method using liquid 

chromatography/mass spectrometry (LC/MS) to look for 

chlorothalonil and its primary degradation product 4-hydroxychlorothalonil in water. The 4-hydroxy-chlorothalonil has 

been reported to have greater stability and toxicity than the 

parent compound (Potter and others, 2001). Two degradation 

products, 1-amide-2-hydroxy-chlorothalonil and 4-hydroxy1,3-diamide-chlorothalonil, were identified in initial method 

development due to their formation while synthesizing the 

4-hydroxy-chlorothalonil for use as a primary standard 

(Rouchaud and others, 1988). Studies have indicated that 

chlorothalonil is degraded by ultraviolet light (Sakkas and 

others, 2002).

The USGS Methods and Research Development Group, 

Lakewood, Colorado, developed a method for chlorothalonil using gas chromatography/mass spectrometry (GC/MS) 

endeavoring to reach a lower LRL (0.01 μg/L) than the USGS 

National Water-Quality Laboratory (NWQL) schedule 2060, 

which analyzes the compound chlorothalonil at a LRL of 

0.035 μg/L.

In addition to analysis of chlorothalonil and its degradation products, samples were analyzed by the USGS National 

Water-Quality Laboratory schedules 2001 and 2060 for about 

114 pesticides and their degradation products. Samples also 

were analyzed for dissolved organic carbon by the USGS 

National Research Program, Boulder, Colorado, and concentrations of suspended sediment and percentage of silt- and 

clay-sized particles were determined by the Marine Sediment 

Laboratory, Marina, California.

Purpose and Scope

The primary purpose of this report is to document the 

results of analyses of the fungicide chlorothalonil and its degradation products in samples from 22 surface-water sampling 

sites in Alabama, Florida, Georgia, Oklahoma, and Texas 

during 2003–04. As part of quantifying chlorothalonil and 

its degradation products in surface water, the report describes 

an analytical method, using solid-phase extraction (SPE) and 

liquid chromatography/mass spectrometry (LC/MS), developed by the USGS Organic Geochemistry Research Laboratory (OGRL), Lawrence, Kansas, and a limited test of a gas 

chromatography/mass spectrometry (GC/MS) method for 

determination of a lower LRL for chlorothalonil developed 

by the USGS Methods and Research Development Group, 

Lakewood, Colorado. The report also describes chlorothalonil usage, selection of sampling sites, sample-collection and 

processing methods, and quality-assurance procedures.

This report also includes the results of analysis of waterquality samples collected at the 22 surface-water sampling 

sites for the occurrence of selected pesticides and their 

degradation products by laboratory schedules 2001 and 2060 

at the USGS National Water-Quality Laboratory (NWQL), 

Lakewood, Colorado, analysis of dissolved organic carbon 

(DOC) by the USGS National Research Program, Boulder, 

Colorado, and analysis of suspended sediment in environmental water samples by the USGS Marine Sediment Laboratory, 

Marina, California. Streamflow discharge measurements, 

gage heights, and physical properties of the water associated 

with each surface-water sample also are presented.

Introduction   
Acknowledgments

This study was supported by the USGS Toxic Substances 

Hydrology Program and conducted with the support of USGS 

Water Science Centers in Alabama, California, Florida, Georgia, Oklahoma, and Texas. The authors would especially like 

to acknowledge the following USGS personnel who collected 

samples and provided logistical support: Lance Wilhelm, 

Mark Reynolds, Brian Hughes, Brian Atkins, Ann McPherson, 

Richard Moreland, John Pittman, Monti Haynie, and Cary 

Carman.

Sampling Methods and Procedures

Sampling-Site Selection Method

A geographic information system (GIS) database was 

created to evaluate relevant spatial and pesticide application 

data on a nationwide scale. Data types in the GIS database 

included land-use/land-cover data, detailed hydrology, watershed boundaries, and chlorothalonil application data circa 

Figure 2. Geographic distribution of chlorothalonil applications at 22 surface-water sampling sites in five Southern States 

(fungicide data from National Center for Food and Agricultural Policy, 1997).

   Results of Analyses of the Fungicide Chlorothalonil, Its Degradation Products, and Other Selected Pesticides

102° 39°

36°

33°

30°

27°

99° 96° 93° 90° 87° 84° 81°

0 75 150 225 300 MILES

0

Base from U.S. Geological Survey digital data, 1:2,000,000, 1994 

Albers Equal-Area Conic projection

Standard parallels 29°30’ and 45°30’, central meridian -96°

Horizontal coordinate information is referenced to the North American

 Datum of 1983 (NAD 83) 75 150 225 300 KILOMETERS

MEXICO

Texas

Oklahoma

Kansas

Missouri

Arkansas

Louisiana

Mississippi

Tennessee

Kentucky

Indiana Illinois

West

Virginia

Virginia

North

Carolina

South

Carolina

Georgia

Alabama

Florida

Gulf of Mexico

Atlantic

Ocean

Fungicide data from National Center for Food and Agricultural Policy, 1997

EXPLANATION

Chlorothalonil application

1,000 to 50,000 pounds

50,000 to 100,000 pounds

Greater than 100,000 pounds

18

20

19

21

7

9

13 12

14 10 17

11

15 16

6

5 1

4

22

2003 sampling site and

 map number

2003 and 2004 sampling site and map number 

7

22

2

3 8
1997, as well as other ancillary data sources. The GIS 

database then was manipulated using the site-selection criteria 

to identify watershed-scale regions in which to locate sampling sites.

During May 2003, USGS personnel evaluated selected 

areas in Alabama, Florida, and Georgia to locate specific sites 

for sampling. During this process, focus was on the prevalence of peanut crops in the potential sampling-site watersheds, as well as associated logistical and safety concerns. 

Sites in Oklahoma and Texas were selected primarily on the 

basis of onsite reconnaissance by local USGS personnel with 

the additional criteria that the sites be collocated with existing 

USGS streamflow-gaging stations.

During 2003, 22 surface-water sites in Alabama, Florida, 

Georgia, Oklahoma, and Texas (fig. 1) were sampled, and 9 of 

the 22 sites were sampled again in 2004 (table 1). The selection of sampling sites in 2004 was based largely upon chlorothalonil detections during the previous year. The selected 

sampling sites for 2003–04 represented areas of varying climate, vegetation, topography, geology, and cropping practices. 

Watershed basin areas for the surface-water sampling sites 

varied from 13 to 783 mi2 (table 1). All the sites represented 

watersheds with abundant peanut acreage and were located in 

counties with substantial amounts of chlorothalonil application (table 1). Chlorothalonil application data circa 1997 are 

shown by county for the watersheds of each site sampled in 

2003–04 (table 1).

Sample Collection

During 2003, each surface-water site was sampled three 

times during the peanut-growing season (June through September) with the exception of one site each in Oklahoma and 

Texas, which were sampled twice. The timing of each sampling was intended to correspond with the timing of chlorothalonil applications in each study area as determined through 

contacts with local county agricultural extension agents. In 

2004, nine surface-water sites were sampled twice, once early 

in the growing season and once just prior to harvest. These 

samples were collected within 48 hours after storms in the 

respective watersheds.

Water samples were collected either by wading or from 

bridges depending upon streamflow conditions and safety 

considerations (Wilde and others, 1999). Wading samples 

were collected during low flows using a USGS DH-81 sampler 

and 1-L Teflon bottle, whereas samples collected during highflow conditions, or where water at the site was too deep to be 

Figure 3. Chemical structures of chlorothalonil and five degradation products

Introduction 

C

N

N

Cl

Cl

Cl C

Cl

N

C

N

OH

Cl

Cl C

Cl

C

H2N

NH2

O

O

Cl

Cl

Cl C

Cl

C

NH2

NH2

O

O

OH

Cl

Cl C

Cl

N

C

C

H2N O

OH

Cl

Cl

Cl

N

C

C

H2N O

Cl

HO

Cl

Cl

Chlorothalonil

(1,3-dicyano-2,4,5,6-

tetrachlorobenzene)

4-hydroxy-chlorothalonil

(1,3-dicyano-4-hydroxy-2,5,6-

trichlorobenzene) 

1,3-diamide-chlorothalonil 

(1,3-dicarbamoyl-2,4,5,6-t

etrachlorobenzene)

1-amide-4-hydroxy-chlorothalonil

(1-carbamoyl-3-cyano-4-hydroxy-2,5,6-

trichlorobenzene)

1-amide-2-hydroxy-chlorothalonil

(1-carbamoyl-2-hydroxy-5-cyano-3,4,6-

trichlorobenzene)

4-hydroxy-1,3-diamide-chlorothalonil

(1,3-dicarbamoyl-2,4,5-trichloro-6-

hydroxybenzene)
Table 1. Site name, location, year sampled, watershed basin size, and amount of chlorothalonil application during 1997 in counties adjacent 

to 22 surface-water sampling sites in five Southern States, 2003–04.

[mi2, square mile]

Map 

number 

(fig. 1)

Site name

Site identification 

number

Latitude 

(degree/

minute/

second)

Longitude 

(degree/minute/second)

Year 

sampled

Watershed 

basin 

size (mi2)

Chlorothalonil 

application 

counties

Chlorothalonil 

application1

(pounds)

Alabama

1 Big Creek at State Highway 

203 near Rehobeth

02358765 31o 04' 49" 85o 25' 53" 2003 26 Geneva, 

Houston

210,051

2 Cedar Creek at East Cook Road 

near Pansey

02343848 31o 11' 07" 85o 09' 00" 2003–04 22 Houston 126,862

3 Cowarts Creek above Cottonwood235878075 31o 06' 19" 85o 15' 17" 2003 44 Houston 126,862

4 Cowarts Creek near Love Hill 235878055 31o 07' 20" 85o 17' 32" 2003 19 Houston 126,862

5 Spring Creek at County Road 

55 near Geneva

02365100 31o 02' 35" 85o 45' 11" 2003 15 Geneva 83,189

Florida

6 Moore Creek near Chumuckla 02375800 30o 48' 35" 87o 15' 14" 2003 22 Santa Rosa 63,189

7 Pond Creek near Milton 02370700 30o 40' 50" 87o 07' 55" 2003–04 59 Santa Rosa 63,189

8 Russ Mill Creek at Union Road 

near Cottondale

02358778 30o 51' 09" 85o 20' 30" 2003 18 Jackson 127,828

9 West Fork Big Coldwater Creek 

near Allentown

02370400 30o 47' 22" 87o 02' 29" 2003 70 Santa Rosa 63,189

Georgia

10 Big Creek at Crystal Lake Road 

near Irwinville

02315919 31o 40' 19" 83o 25' 12" 2003 34 56,310 2003

11 Black Creek near Blitchton 02202600 32o 10' 04" 81o 29' 18" 2003–04 232 70,158 2003–04

12 Bridge Creek at James King 

Road near Doerun

02327314 31o 17' 15" 85o 57' 19" 2003–04 13 185,465 2003–04

13 Coheelee Creek at River Road 

near Hilton

02343410 31o 18' 22" 85o 04' 43" 2003–04 21 83,897 2003–04

14 Little Abrams Creek at GA 

Highway 313 near Doles

02350522 31o 41' 13" -- 2003–04 19 168,166 2003–04

15 Reedy Creek at U.S. Highway 

129 near Ocilla

02316217 31o 29' 59" 83o 14' 19" 2003 49 56,310 2003

16 Warrior Creek near Sumner 02317870 31o 21' 45" 83o 46' 11" 2003–04 109 106,401 2003–04

17 Willacoochee Creek at Frank 

Road near Ocilla

02316134 31o 37' 21" 83o 12' 58" 2003 54 79,893 2003

Oklahoma

18 Cobb Creek near Eakly 07325800 35o 17' 26" 98o 35' 38" 2003–04 132 Caddo, Washita 51,712

19 Cobb Creek near Fort Cobb 07326000 35o 08' 37" 98o 26' 33" 2003–04 307 Caddo, Washita 51,712

 Results of Analyses of the Fungicide Chlorothalonil, Its Degradation Products, and Other Selected Pesticides
waded safely, used a USGS D-95 weighted sampler with a 1-L 

Teflon bottle and bridgeboard cable-reel device. Sampling 

was conducted using the equal-width-increment method as 

described in Shelton (1994). During sampling, in-situ measurements were made of water physical properties (specific 

conductance, pH, temperature, and dissolved oxygen concentrations) using a hand-held multiparameter meter. Stream 

stage and discharge measurements also were collected each 

time water-quality samples were collected, following standard 

USGS procedures (Buchanan and Somers, 1969). Samples for 

analysis of suspended-sediment concentration and percentage 

of silt- and clay-sized particles (less than 0.062 mm in diameter) were collected by submerging a 500-mL glass bottle in 

the center of flow and were not processed prior to shipment.

In addition to the standard sampling conducted at all 

sites in both years, samples were collected at one site (Black 

Creek near Blitchton, Georgia, map number 11, fig. 1) using 

an ISCO Model 3700 portable automatic sampler (Teledyne 

ISCO, Los Angeles, California). This sampling method was 

used so that samples could be collected automatically every 

30 to 60 minutes without the need for personnel onsite and in 

response to rising stage associated with storms near the site. 

The sampler was mounted in a specially designed aluminum 

housing attached to the side of a road bridge spanning Black 

Creek. The sampler used a Teflon inlet hose that was attached 

to a bridge pile near the center of flow and immediately adjacent to a USGS gaging station located at the site. Sampling 

was triggered either by a rise in stream stage as detected by 

the sampler or manually. During a sampled storm, the instrument first purged the sampling line to reduce the chances of 

contamination between samples and then pumped a preset 

volume of sample water into an open-mouthed, pre-cleaned, 

1-L glass or polypropylene bottle contained within the sealed 

sampler housing. During this study, the autosampler typically was programmed to collect 2 L of water every hour for 

6 consecutive hours during the initial period of rising stream 

stage. Samples were removed from the autosampler by USGS 

personnel within 6 to 12 hours of collection and processed for 

shipment.

Sample Processing

Onsite sample processing was conducted after collection of the samples using USGS procedures (Shelton, 1994; 

Shelton and Capel, 1994). Upon collection, water from 

the equal-discharge increment profile or autosampler was 

poured into a 14-L Teflon churn where it was composited and 

homogenized. All samples for pesticide analysis were filtered 

through 0.7-μm baked, glass-fiber filters. These samples then 

were filtered directly into 1-L or 125-mL baked, amber glass 

bottles in accordance with the laboratory schedule as listed in 

table 2. Water samples collected using the autosampler were 

processed in the same manner and analyzed only for pesticides 

and pesticide degradation products.

 Quality-assurance samples included pesticide field spike, 

field replicate, and blank samples that were processed in an 

identical manner to environmental samples. Certified-grade 

blank water for pesticide spike solution and blank samples 

were obtained from the USGS NWQL. Additional information about quality-assurance samples is provided in the ‘Quality Assurance’ section of this report.

Water samples collected for dissolved organic carbon 

analysis were filtered separately using single 47-mm glassfiber filters and 0.7-μm, pre-combusted glass microfiber filters. 

The dissolved organic carbon samples then were filtered into 

125-mL baked, amber glass bottles. Water samples for suspended sediment were collected in 500-mL baked, amber glass 

bottles. All samples were shipped on ice within 24 hours to 

the appropriate laboratories (table 2).

Table 1. Site name, location, year sampled, watershed basin size, and amount of chlorothalonil application during 1997 in counties adjacent 

to 22 surface-water sampling sites in five Southern States, 2003–04.—Continued

[mi2, square mile]

Map 

number 

(fig. 1)

Site name

Site identification 

number

Latitude 

(degree/

minute/

second)

Longitude 

(degree/minute/second)

Year 

sampled

Watershed 

basin 

size (mi2)

Chlorothalonil 

application 

counties

Chlorothalonil 

application1

(pounds)

Texas

20 Beaver Creek near Electra 07312200 33o 54' 21" 98o 54' 17" 2003 652 Foard, Wichita, 

Willbarger

2,965

21 Sabana River near DeLeon 08099300 32o 06' 50" 98o 36' 19" 2003 264 Comanche, 

Eastland

20,592

22 San Miguel Creek near Tilden 08206700 28o 35' 14” 98o 32' 44” 2003 783 Atascosa, Frio, 

McMullen, 

Medina

44,778

1

Chlorothalonil application data from National Center for Food and Agricultural Policy (1997).

Introduction 
Analytical Methods and Procedures

Analysis of Chlorothalonil and Its Degradation 

Products by Liquid Chromatography/Mass 

Spectrometry

Analytical methods for chlorothalonil and its three 

principle degradation products were developed by the USGS 

OGRL in Lawrence, Kansas, and are described in this section. 

The methods include SPE LC/MS using atmospheric pressure 

chemical ionization (APCI) or electrospray ionization (ESI) 

in negative-ion mode. The APCI method was used to analyze 

chlorothalonil and three degradation products during 2003 at 

an LRL of 0.050 μg/L. To improve sensitivity and minimize 

background matrix interferences, water-quality samples collected during 2004 were analyzed by two separate LC/MS 

methods with the same sample extract. Although LRLs 

ranged from 0.020 to 0.050 μg/L, compounds were detected at 

estimated concentrations as low as 0.002 μg/L depending on 

the sample matrix. As a research method, LRLs were established on the basis of reagent spikes at levels five times above 

the background. The APCI method measured chlorothalonil 

and 1,3-diamide-chlorothalonil, and the ESI method measured 

4-hydroxy-chlorothalonil and 1-amide-4-hydroxy-chlorothalonil. All four compounds could be determined using the APCI 

method, but the ESI method was approximately 10 to 20 times 

more sensitive to the presence of the 4-hydroxy-chlorothalonil 

degradation product. Chlorothalonil and 1,3-diamide-chlorothalonil did not ionize efficiently using the ESI method.

Materials

Chlorothalonil was obtained from Chem Service, Inc. 

(Westchester, Pennsylvania). The chlorothalonil degradation 

product 4-hydroxy-chlorothalonil was obtained from the U.S. 

Environmental Protection Agency (USEPA) repository (Fort 

Meade, Maryland). 1,3-diamide-chlorothalonil and 1-amide–

4-hydroxy-chlorothalonil were synthesized using the method 

of Rouchaud and others (1988) with added purification using 

flash chromatography and concentrated by lypholyzation. 

The surrogate standard, 2,4-dichlorophenoxyacetic acid-D3, 

and internal standard (ISTD), pentachlorophenol-13C6, were 

obtained from Cambridge Isotope Laboratory (Andover, Massachusetts). All solvents were high-performance liquid chromatography (HPLC) grade, and the acetic acid was American 

Chemical Society (ACS) certified.

Atmospheric Pressure Chemical Ionization 

Method Used in 2003

A 1.23-ng/mL working standard mix of chlorothalonil, 

4-hydroxy-chlorothalonil, 1,3-diamide-chlorothalonil, and 1-

amide-4-hydroxy-chlorothalonil was prepared in acetonitrile. 

A 2-ng/mL working standard of 2,4-dichlorophenoxyacetic 

acid-D3 was prepared in methanol. The working standard of 

pentachlorophenol-13C6 was prepared by diluting the stock to 

0.5 μg/mL in 96/4 acetonitrile/isopropanol.

Blank samples and calibration standards were prepared 

in buffered reagent water, pH 7.0, at 0.05-, 0.10-, 0.20-, 0.50-, 

1.00-, and 2.00-μg/L concentrations by diluting directly into 

baked 123-mL amber bottles. Buffered reagent water was prepared by adding 2 mL of 0.1 M phosphate buffer (adjusted to 

pH 7.0 standard units with phosphoric acid) to the bottle prior 

to filling with deionized water. All blank samples, calibration 

standards, and unknown samples were spiked with 50 μL of 

the surrogate standard, 2,4-dichlorophenoxyacetic acid-D3.

Solid-phase extraction (SPE) was performed on a Zymark 

Autotrace (Zymark, Palo Alto, California) using Waters 

Oasis hydrophilic-lipophilic-balanced (HLB) 500-mg/6-cm3

cartridges (Waters, Milford, Massachusetts) to analyze water 

Table 2. Type of analysis, number of bottles, sample volume, and year collected for surface-water samples collected from five 

Southern States, 2003–04.

[MSL, Marine Sediment Laboratory, Marina, California; NRP, U.S. Geological Survey National Research Program, Boulder, Colorado; NWQL, U.S. 

Geological Survey National Water-Quality Laboratory, Lakewood, Colorado; OGRL, U.S. Geological Survey Organic Geochemistry Research Laboratory, 

Lawrence, Kansas; mL, milliliter; L, liter]

Laboratory Type of analysis Number of bottles 

and sample volume Year collected

MSL Suspended-sediment concentration and percentage of silt- and clay-sized particles 1 x 500 mL 2003–04

NRP Dissolved organic carbon (DOC) 2 x 125 mL 2003–04

NWQL Schedule 2001 pesticides and degradation products 1 x 1 L 2003–04

NWQL Schedule 2060 pesticides and degradation products 1 x 1 L 2003–04

OGRL Acetamide herbicides and acetamide degradation products (laboratory code LCPD) 2 x 125 mL 2004

OGRL Chlorothalonil and degradation products 4 x 125 mL 2003–04

OGRL Chlorothalonil and degradation products (field spike) 1 x 125 mL 2003–04

 Results of Analyses of the Fungicide Chlorothalonil, Its Degradation Products, and Other Selected Pesticides
samples collected in 2003. Cartridges were rinsed with 3 mL 

acetonitrile at a flow rate of 1 mL/min and equilibrated with 

3 mL reagent water at a flow rate of 1 mL/min. The 123-mL 

sample was loaded onto the cartridge at a flow rate of 

10 mL/min and kept under vacuum for 30 seconds after 

loading. Compounds then were eluted from the column with 

3 mL acetonitrile at a flow rate of 1 mL/min. One hundred 

microliters (100 μL) of the ISTD solution, pentachlorophenol- 13C6

 (0.5 μg/mL), were added to the sample tubes. Sample 

eluates were reduced to a volume of 100 μL using a Zymark 

turbovap with nitrogen evaporation at 15 lb/in2 with a water 

bath at 35 oC. Sample extracts were not allowed to go to 

dryness. The extracts then were transferred to 0.10-mL amber 

vials, capped, labeled, and stored in a freezer at –10 oC until 

analysis.

Samples were analyzed on an Agilent 1100 model D 

series LC/MS using the APCI spray chamber in negativeion mode with selected-ion monitoring. The compounds 

were separated using a Luna 3-μm, 150- x 2-mm C-18 (2) 

LC column (Phenomenex, Torrance, California). The LC 

injection volume was 25 μL, which was mixed with 10 μL of 

2.5-percent acetic acid using the programming function of the 

autosampler.

The APCI spray chamber was operated using the conditions as shown in table 3. The mobile-phase composition 

(which is the solvent that carries the analyte through the 

column) was used with the APCI negative-ion mode. MobileTable 3. Operating conditions of liquid chromatograph/mass spectrometer using atmospheric pressure chemical ionization and electrospray ionization for analysis of samples from 22 surface-water sampling sites in five Southern States, 2003–04.

[APCI, atmospheric pressure chemical ionization; ESI, electrospray ionization; oC, degrees Celsius; L/min, liter per minute; lb/in2, pounds per square inch; 

kV, kilovolt; μA, microamp; V, volt; v, volume; min, minute; mM, millimolar; DI, deionized; H2O, water; %, percent; --, not applicable] 

Measurement APCI 2003 negative ion ESI negative ion

Gas temperature 300 oC --

Vaporizer temperature 350 oC --

Drying gas flow 9.0 L/min --

Nebulizer pressure 30 lb/in2 --

Capillary voltage 2.0 kV --

Corona current 15 μA --

Fragmentation 100 V --

Gain 1.0 --

Dwell 35 milliseconds --

Peak width 0.15 min --

Mobile-phase A 5 mM ammonium acetate --

Mobile-phase B acetonitrile --

Measurement APCI 2004 negative ion ESI negative ion

Gas temperature 300 oC 300 oC

Vaporizer temperature 350 oC 350 oC

Drying gas flow 9.0 L/min 9.0 L/min

Nebulizer pressure 30 lb/in2 30 lb/in2

Capillary voltage 3,000 V 3,000 V 

Corona current 2.5 μA --

Fragmentation 100 V 100 V

Gain 1.0 1.0

Dwell 35 milliseconds 27 milliseconds

Peak width 0.15 min 0.15 min

Mobile-phase A negative 5 mM ammonium acetate 2.5 mM ammonium acetate in DI water adjusted

 in DI water using acetic acid to pH 3.7 standard units 

Mobile-phase B negative Isopropanol/acetonitrile/H2O Acetonitrile 

49.75%/49.75%/0.5% v/v/v)

Analytical Methods and Procedures 
phase A consisted of ammonium acetate in deionized water, 

and mobile-phase B consisted of acetonitrile. The mass 

spectrometer was turned on at 3 min and turned off at 25 min 

(table 3).

Atmospheric Pressure Chemical Ionization and 

Electrospray Ionization Methods Used in 2004

A standard mix solution was prepared from individual 

1-mg/mL stock solutions of chlorothalonil, 4-hydroxy-chlorothalonil, 1-amide–4-hydroxy-chlorothalonil, and 1,3-diamidechlorothalonil at 2.46 ng/μL, and 2,4-dichlorophenoxyacetic 

acid-D3 and pentachlorophenol-13C6 at 4.92 ng/μL. In a 2-mL 

autosampler vial, 100 μL of the standard mix were added 

to 700 μL deionized water. Blank solution for the standard 

addition was prepared in a 2-mL autosampler vial by adding 

100 μL acetonitrile to 700 μL deionized water. Extracts were 

transferred to 0.1-mL amber vials, capped, labeled, and stored 

in freezer at -10 oC until analysis.

The 123-mL blank sample was prepared using deionized 

water with 2 mL buffer solution. Then 50 μL of 1.23-μg/mL 

surrogate standard solution and 100 μL glacial acetic acid 

were added to all environmental and blank samples. Each SPE 

cartridge was rinsed by mounting the cartridges on the vacuum 

manifold and passing 5 mL acetonitrile and 5 mL deionized 

water through each cartridge. The samples then were loaded 

onto the SPE cartridges.

SPE was performed on a Zymark Autotrace using Waters 

HLB 500-mg/6-cm3 cartridges to elute compound with 8 mL 

of 0.75-percent ammonium hydroxide in acetonitrile. One 

hundred microliters (100 μL) of the ISTD solution, pentachlorophenol-13C6

, and 15 μL of glacial acetic acid then were 

added to each sample tube. A second test tube was placed in 

the vacuum rack, and the cartridges were eluted with another 

8 mL of 0.75-percent ammonium hydroxide in acetonitrile. 

Sample eluates then were reduced in each of the two test tubes 

to a volume of 2 to 4 mL, and the eluate of the two test tubes 

was combined. Sample eluates then were reduced to a volume 

of 200 μL using a Zymark turbovap. Sample extracts were 

transferred to 250-μL autosampler vials, capped, and labeled.

Compounds then were eluted from the cartridge with 

8 mL of 0.75-percent ammonium hydroxide in acetonitrile. 

One hundred microliters (100 μL) of the ISTD solution, pentachlorophenol-13C6

, and 15 μL of glacial acetic acid then were 

added to each sample tube. A second test tube was placed in 

the vacuum rack, and the cartridges were eluted with another 

8 mL of 0.75-percent ammonium hydroxide in acetonitrile. 

Sample eluates then were reduced in each of the two test tubes 

to a volume of 2 to 4 mL, and the eluate of the two test tubes 

was combined. Sample eluates then were reduced to a volume 

of 200 μL using a Zymark turbovap. Sample extracts were 

transferred to 250-μL autosampler vials, capped, labeled, and 

stored in a freezer at –10 oC until analysis.

An Agilent 1100 model D series liquid chromatography/

mass spectrometry (LC/MS) using APCI and ESI was used to 

analyze chlorothalonil and its diamide degradation product. 

The compounds were measured using the APCI negative-ion 

mode, and 4-hydroxy-chlorothalonil and 1-amide-4-hydroxychlorothalonil were measured using ESI negative-ion mode, 

which is more sensitive than APCI for these two compounds. 

Mobile-phase A and B compositions used for the APCI and 

ESI methods and MS conditions are listed in table 3. The LC 

autosampler was programmed to inject 25 μL of environmental sample and 25 μL of blank solution onto the column. The 

LC autosampler then took up 25 μL of environmental sample 

and 25 μL of standard addition mix and injected them onto 

the column. The difference in the ratio of the detected analyte 

to the internal standard in the unspiked and spiked samples 

then was used to calculate the concentration in the unspiked 

sample.

Identification and Quantitation

All compounds in this method, including the internal and 

surrogate standards, contained from two to five chlorine atoms 

(fig. 3). The low molecular weight and chemical structure of 

the compounds with their benzene ring, where the chlorine 

atoms were attached, were not easy to fragment in the mass 

spectrometer. However, the signature of the chlorine atoms, 

along with retention times relative to the standards, made 

identification accurate.

Analysis of Chlorothalonil by Gas 

Chromatography/Mass Spectrometry

The USGS Methods and Research Development Group, 

Lakewood, Colorado, developed a custom method for analysis 

of chlorothalonil by gas chromatography/mass spectrometry 

(GC/MS) in an effort to achieve a lower LRL than the USGS 

National Water-Quality Laboratory (NWQL) schedule 2060, 

which analyzes the compound chlorothalonil at a LRL of 

0.035 μg/L (table 4). Chlorothalonil was determined in filtered water samples by C-18 SPE and GC/MS.

Solid-Phase Extraction

The extraction and analysis procedures for SPE are 

described in Zaugg and others (1995) and Sandstrom and others (2001). Briefly, a 1-L water sample was filtered through a 

0.7-μm glass-fiber filter onsite. The sample then was shipped 

to the laboratory. At the laboratory, after addition of surrogate standards, diazinon-d10 and alpha HCH-d6

, and methanol 

conditioner, the sample was pumped through a C-18 SPE 

column at about 25 mL/min. The SPE column then was dried 

with nitrogen and eluted with about 3 mL ethyl acetate into a 

test tube containing a 100-μL aliquot of toluene containing the 

polycyclic aromatic hydrocarbons (PAH) internal standards. 

After evaporation of the ethyl acetate, the sample extract in 

10 Results of Analyses of the Fungicide Chlorothalonil, Its Degradation Products, and Other Selected Pesticides
Quality Assurance 11

Table 4. Compounds analyzed in samples from 22 surface-water sampling sites in five Southern States using U.S. Geological 

Survey National Water-Quality Laboratory (Lakewood, Colorado) schedules 2001 and 2060, 2003–04. 

[μg/L, micrograms per liter]

Pesticide compound

schedule 2001

Laboratory

reporting level

(μg/L)

Pesticide compound

schedule 2060

Laboratory

reporting level

(μg/L)

2,6-diethylaniline 0.006 2,4-D 0.038

acetochlor .006 2,4-D methyl ester .016

alachlor .005 2,4-DB .020

alpha-HCH .005 2-hydroxyatrazine .032

atrazine .007 3-(4-chlorophenyl)-1-methyl urea .036

azinphos-methyl .050 3-hydroxycarbofuran .008

benfluralin .010 3-ketocarbofuran .020

butylate .004 acifluorfen .028

carbaryl .041 aldicarb .040

carbofuran .020 aldicarb sulfone .018

chlorpyrifos .005 aldicarb sulfoxide .022

cis-permethrin .006 atrazine .008

cyanazine .018 bendiocarb .020

dacthal (DCPA) .003 benomyl .022

deethylatrazine (DEA) .006 bensulfuron-methyl .018

desulfinylfipronil .012 bentazon .012

desulfinylfipronil amide .029 bromacil .018

diazinon .005 bromoxynil .028

dieldrin .009 caffeine .018

disulfoton .021 carbaryl .018

EPTC (s-ethyl dipropylthiocarbamate) .004 carbofuran .016

ethalfluralin .009 chloramben, methyl ester .024

ethoprophos .005 chlordiamino-s-triazine .022

fipronil .016 chlorimuron-ethyl .032

fipronil sulfide .013 chlorothalonil .035

fipronil sulfone .024 clopyralid .024

fonofos .003 cycloate .014

lindane .004 dacthal monoacid .028

linuron .035 deethylatrazine (DEA) .028

malathion .027 deisopropylatrazine (DIA) .080
Table 4. Compounds analyzed in samples from 22 surface-water sampling sites in five Southern States using U.S. Geological 

Survey National Water-Quality Laboratory (Lakewood, Colorado) schedules 2001 and 2060, 2003–04.—Continued

[μg/L, micrograms per liter]

Pesticide compound

schedule 2001

Laboratory

reporting level

(μg/L)

Pesticide compound

schedule 2060

Laboratory

reporting level

(μg/L)

metolachlor 0.006 dicamba 0.038

metribuzin .006 dichlorprop .028

molinate .003 dinoseb .038

napropamide .007 diphenamid .010

p,p’-DDE .003 diuron .015

parathion .010 fenuron .032

parathion-methyl .015 flumetsulam .040

pebulate .004 fluometuron .016

pendimethalin .022 imazaquin .036

phorate .011 imazethapyr .038

prometon .010 imidacloprid .020

propachlor .025 linuron .014

propanil .011 MCPA .030

propargite .023 MCPB .010

propyzamide .004 metalaxyl .012

simazine .005 methiocarb .010

tebuthiuron .016 methomyl .020

terbacil .034 metsulfuron methyl .025

terbufos .017 neburon .012

thiobencarb .010 nicosulfuron .040

tri-allate .006 norflurazon .020

trifluralin .009 oryzalin .012

oxamyl .030

picloram .032

propham .030

propiconazole .010

propoxur .008

siduron .020

sulfometuron-methyl .038

tebuthiuron .032

terbacil .016

triclopyr .026

12 Results of Analyses of the Fungicide Chlorothalonil, Its Degradation Products, and Other Selected Pesticides
toluene was transferred to a GC vial, followed by one rinse 

with about 100 μL toluene.

Gas Chromatography/Mass Spectrometry

The water-sample extracts were analyzed for pesticides 

by GC/MS operated in the selected-ion monitoring (SIM) 

mode. The approximate retention time for chlorothalonil was 

21.26 minutes. The 264 and 266 mass-to-charge (m/z) ions 

with 100- and 129- percent abundance, respectively, were 

used for quantitation. The 124 and 229 m/z ions, with 17- and 

13-percent abundance, respectively, were used as confirming 

quantitation ions.

Analysis of Other Pesticides and Their 

Degradation Products

Water samples shipped to the NWQL were analyzed 

for 52 pesticides and degradation products using laboratory 

schedule 2001 and 62 pesticides and degradation products 

using laboratory schedule 2060. Analytes for these laboratory schedules are listed in table 4. Details of the analytical 

methods for NWQL schedules 2001 and 2060 can be found in 

Zaugg and others (1995), Furlong and others (2001), Sandstrom and others (2001), and Madsen and others (2003).

Determination of Dissolved Organic Carbon

Water samples were analyzed for dissolved organic carbon concentrations by the National Research Program, Branch 

of Regional Research, Boulder, Colorado (Aiken, 1992; Aiken 

and others, 1992). Dissolved organic carbon measurements 

using the catalyzed persulfate wet oxidation method were 

made on an O.I. Analytical Model 700 TOC Analyzer (O.I. 

Corporation, College Station, Texas). The instrument was 

warmed up for 24 hours before analyzing samples. Samples 

and calibration standards were loaded onto an autosampler for 

analysis and introduced into the reaction vessel by means of 

a fixed-volume sample loop. The volume of the sample loop 

was constrained by the desire to maintain linear instrument 

response (0 to 50 μg of carbon). The standard automated analytical conditions called for 0.5 mL of 5-percent-by-volume 

phosphoric acid to be added to the sample. The sample then 

was purged for 2.0 minutes with nitrogen to remove inorganic carbon after which 0.5 mL of 0.42-m sodium persulfate 

solution was added. The standard reaction time of 5 minutes 

was employed for the persulfate oxidation step. The instrument was calibrated with solutions of reagent-grade potassium 

hydrogen phthalate (KHP) in distilled water. The standard 

curve, consisting of a minimum of five standards over the 

range of interest, was repeated for every eight water samples 

analyzed in duplicate. Reported values are the averages of 

duplicate analyses. The standard deviation for dissolved 

organic carbon measurements was determined to be ±0.2 mg 

(Aiken, 1992).

Analysis of Suspended Sediment

Unfiltered water samples were analyzed for suspendedsediment concentrations and percentage of silt- and claysized particles (less than 0.062 mm in diameter) at the USGS 

Marine Sediment Laboratory in Marina, California. Details of 

the analytical method can be found in Guy (1969). Analytical 

results of single-blind quality-control samples provided by the 

USGS Sediment Laboratory Quality Assurance Project show 

that laboratory performance during the period of this study 

was satisfactory (U.S. Geological Survey, 2005).

Quality Assurance

All water-quality measurements and water samples for 

this study were collected by USGS personnel in accordance 

with a written work plan for the study (on file with the USGS, 

Sacramento, California). Onsite quality assurance required all 

bottles and sampling equipment to be cleaned by washing the 

glass containers, filter units, and tubing with a phosphate-free 

laboratory detergent and rinsing with tapwater, then rinsing 

with organic-free, deionized, or distilled water, rinsing with 

methanol, and rinsing again with organic-free water to remove 

traces of methanol. Bottles were inverted to drain and dry.

Analysis of Chlorothalonil and Its Degradation 

Products by Liquid Chromatography/Mass 

Spectrometry

Quality-assurance samples for chlorothalonil and its three 

degradation products collected during 2003–04 and analyzed 

by LC/MS at the OGRL consisted of 10 field blanks, 11 field 

replicates, and 13 chlorothalonil spikes as shown in table 5. 

Chlorothalonil or its degradation products were not detected in 

any of the 11 field blanks. The field replicates were analyzed 

to estimate method precision at ambient chlorothalonil concentrations in the presence of sample-collection and samplematrix interferences. The chlorothalonil field-spiked samples 

were prepared by the collector and submitted with the environmental sample for analysis at a concentration of 0.25 μg/L. 

Spikes of environmental samples are useful in determining the 

effect of a particular matrix on analyte recovery. Laboratoryspiked samples (LS) were fortified at 1.0 μg/L for chlorothalonil, 1-3, diamide chlorothalonil, 1 amide-4-hydroxy-chlorothalonil, and 4-hydroxy-chlorothalonil. The concentration of 

these compounds varied from less than the LRL to 1.6 μg/L. 

The field replicates (FR) all agreed, and neither chlorothalonil 

nor its degradation products were detected in any of the field 

blanks.

Quality Assurance 13
Table 5. Concentrations of chlorothalonil and three chlorothalonil degradation products in quality-assurance samples from surfacewater sampling sites in five Southern States as determined by U.S. Geological Survey Organic Geochemistry Research Laboratory, 

Lawrence, Kansas, 2003–04. 

[Sample type: FB, field blank; FCS, field chlorothalonil spike; FR, field replicate; LD, laboratory duplicate; LS, laboratory spike; R, regular environmental; 

<, less than; --, no data] 

Map

number

(fig. 1)

Site location

Date of

collection

(month/day/

year)

Collection time

(24-hour)

Sample

type

Concentrations, in micrograms per liter

Chlorothalonil

1-3,

diamidechlorothalonil

1 amide4-hydroxychlorothalonil

4-hydroxychlorothalonil

Alabama

1 Big Creek at State Highway 203 near 

Rehobeth

09/17/03 1220 R <0.050 <0.050 <0.050 <0.050

09/17/03 1221 FR <.050 <.050 <.050 <.050

2 Cedar Creek at East Cook Road near 

Pansey

08/04/03 1105 R <.050 <.050 <.050 .110

08/04/03 1106 FR <.050 <.050 <.050 .050

06/15/04 1250 R <.020 <.050 .020 .066

06/15/04 1255 FCS .160 <.050 .016 .076

06/15/04 1240 FB <.020 <.050 <.020 <.020

3 Cowarts Creek above Cottonwood 08/05/03 0900 R <.050 <.050 <.050 <.050

08/05/03 0900 LS 1.04 <.050 1.36 1.29

4 Cowarts Creek near Love Hill 08/05/03 1300 R <.050 <.050 <.050 <.050

08/05/03 1300 LD <.050 <.050 <.050 <.050

5 Spring Creek at County Road 55 near 

Geneva

06/25/03 0810 R <.050 <.050 <.050 <.050

06/25/03 0810 LD <.050 <.050 <.050 <.050

09/17/03 0900 R <.050 <.050 <.050 <.050

09/17/03 0800 FB <.050 <.050 <.050 <.050

Florida

6 Moore Creek near Chumuckla 07/29/03 1225 R <.050 <.050 <.050 <.050

07/29/03 1145 LD <.050 <.050 <.050 <.050

07/29/03 1145 FB <.050 <.050 <.050 <.050

09/25/03 1200 R <.050 <.050 <.050 <.050

09/25/03 1200 LD <.050 <.050 <.050 <.050

09/25/03 1202 FCS .080 <.050 <.050 <.050

14 Results of Analyses of the Fungicide Chlorothalonil, Its Degradation Products, and Other Selected Pesticides
Quality Assurance 15

Table 5. Concentrations of chlorothalonil and three chlorothalonil degradation products in quality-assurance samples from surfacewater sampling sites in five Southern States as determined by U.S. Geological Survey Organic Geochemistry Research Laboratory, 

Lawrence, Kansas, 2003–04.—Continued

[Sample type: FB, field blank; FCS, field chlorothalonil spike; FR, field replicate; LD, laboratory duplicate; LS, laboratory spike; R, regular environmental; 

<, less than; --, no data] 

Map

number

(fig. 1)

Site location

Date of

collection

(month/day/

year)

Collection time

(24-hour)

Sample

type

Concentrations, in micrograms per liter

Chlorothalonil

1-3,

diamidechlorothalonil

1 amide4-hydroxychlorothalonil

4-hydroxychlorothalonil

Florida—Continued

7 Pond Creek near Milton 06/14/04 1310 R <0.020 <0.050 <0.020 <0.020

06/14/04 1315 FCS .123 <.050 <.020 .005

09/23/04 0830 R <.020 <.050 <.020 .007

09/23/04 0830 LS .072 <.050 <.020 .006

09/23/04 0835 FR <.020 <.050 <.020 .005

9 West Fork Big Coldwater Creek near 

Allentown

06/24/03 0900 R <.050 <.050 <.050 <.050

06/24/03 0745 FB <.050 <.050 <.050 <.050

09/25/03 0845 R <.050 <.050 <.050 <.050

09/25/03 0845 LS 1.19 1.50 1.56 .960

Georgia

10 Big Creek at Crystal Lake Road near 

Irwinville

09/24/03 0715 R <.050 <.050 <.050 <.050

09/24/03 0716 FR <.050 <.050 <.050 <.050

11 Black Creek near Blichton 09/08/03 0930 R <.050 <.050 <.050 <.050

09/08/03 0930 LS 1.08 <.050 .920 .940

09/08/03 0945 R <.050 <.050 <.050 <.050

09/08/03 0945 LD <.050 <.050 <.050 <.050

09/22/03 1230 R <.050 <.050 <.050 <.050

09/22/03 1232 FCS .240 <.050 <.050 <.050

09/22/03 1232 LS .730 <.050 <.050 1.18

10/18/03 2030 R <.050 <.050 <.050 <.050

10/18/03 2030 LS .260 <.050 1.23 1.62

06/23/04 0430 R <.020 <.050 <.020 .009

06/23/04 0432 FCS .252 <.050 <.020 .021

06/23/04 0930 R <.020 <.050 <.020 .008

06/23/04 0932 FCS .048 <.050 <.020 .015

06/24/04 0915 R <.020 <.050 <.020 .013

06/24/04 0915 LS .456 <.050 <.020 .013

06/24/04 0916 FCS .248 <.050 <.020 .009
Table 5. Concentrations of chlorothalonil and three chlorothalonil degradation products in quality-assurance samples from surfacewater sampling sites in five Southern States as determined by U.S. Geological Survey Organic Geochemistry Research Laboratory, 

Lawrence, Kansas, 2003–04.—Continued

[Sample type: FB, field blank; FCS, field chlorothalonil spike; FR, field replicate; LD, laboratory duplicate; LS, laboratory spike; R, regular environmental; 

<, less than; --, no data] 

Map

number

(fig. 1)

Site location

Date of

collection

(month/day/

year)

Collection time

(24-hour)

Sample

type

Concentrations, in micrograms per liter

Chlorothalonil

1-3,

diamidechlorothalonil

1 amide4-hydroxychlorothalonil

4-hydroxychlorothalonil

Georgia—Continued

11 Black Creek near Blichton—Continued 09/07/04 1540 R <0.020 <0.050 <0.020 <0.020

09/07/04 1540 LS .055 <.050 <.020 .011

12 Bridge Creek at James King Road near 

Doerun

07/15/03 1150 R <.050 <.050 <.050 <.050

07/15/03 1150 LS .990 1.21 .950 1.51

09/23/03 0800 R <.050 <.050 <.050 <.050

09/23/03 0800 LD <.050 <.050 <.050 <.050

09/23/03 0801 FB <.050 <.050 <.050 <.050

07/08/04 1900 R <.020 <.050 <.020 .019

07/08/04 1900 LS .114 <.050 <.020 .025

13 Coheelee Creek at River Road near 

Hilton

09/15/03 1220 R <.050 <.050 <.050 <.050

09/15/03 1220 LD <.050 <.050 <.050 <.050

09/15/03 1221 FR <.050 <.050 <.050 <.050

06/15/04 1510 R <.020 <.050 <.020 .031

06/15/04 1515 FCS .109 <.050 <.020 .032

14 Little Abrams Creek at GA Highway 

313 near Doles

08/12/03 1300 R <.050 <.050 <.050 <.050

08/12/03 1301 FR <.050 <.050 <.050 <.050

08/12/03 1301 LS .890 <.050 <.050 1.61

07/08/04 1030 R .433 <.050 <.020 .930

07/08/04 1030 FCS .369 <.050 <.020 .754

07/08/04 0955 FB <.020 <.050 <.020 <.020

07/08/04 1215 R .150 <.050 <.020 .350

07/08/04 1215 LD .150 <.050 <.020 .350

15 Reedy Creek at U.S. Highway 129 near 

Ocilla

08/13/03 1345 R <.050 <.050 <.050 <.050

08/13/03 1345 LD <.050 <.050 <.050 <.050

16 Warrior Creek near Sumner 07/15/03 750 R <.050 <.050 <.050 <.050

07/15/03 0751 FR <.050 <.050 <.050 <.050

16  Results of Analyses of the Fungicide Chlorothalonil, Its Degradation Products, and Other Selected Pesticides
Table 5. Concentrations of chlorothalonil and three chlorothalonil degradation products in quality-assurance samples from surfacewater sampling sites in five Southern States as determined by U.S. Geological Survey Organic Geochemistry Research Laboratory, 

Lawrence, Kansas, 2003–04.—Continued

[Sample type: FB, field blank; FCS, field chlorothalonil spike; FR, field replicate; LD, laboratory duplicate; LS, laboratory spike; R, regular environmental; 

<, less than; --, no data] 

Map

number

(fig. 1)

Site location

Date of

collection

(month/day/

year)

Collection time

(24-hour)

Sample

type

Concentrations, in micrograms per liter

Chlorothalonil

1-3,

diamidechlorothalonil

1 amide4-hydroxychlorothalonil

4-hydroxychlorothalonil

Oklahoma

18 Cobb Creek near Eakly 07/15/03 1030 R <0.050 <0.050 <0.050 <0.050

07/15/03 1033 FR <.050 <.050 <.050 <.050

07/30/03 1200 R <.050 <.050 <.050 <.050

07/30/03 1202 FR <.050 <.050 <.050 <.050

08/15/04 1630 R <.020 <.050 <.020 .002

08/15/04 1630 LD <.020 <.050 <.020 .002

08/15/04 1630 LS <.020 <.050 <.020 .002

08/15/04 1632 FCS .189 <.050 <.020 .009

08/15/04 1636 FB <.020 <.050 <.020 <.020

08/28/04 1700 R <.020 <.050 <.020 .018

08/28/04 1700 LD <.020 <.050 <.020 .012

10/07/04 2130 R <.020 <.050 <.020 <.020

10/07/04 2132 FCS .109 <.050 <.020 .007

19 Cobb Creek near Fort Cobb 07/17/03 1430 R <.050 <.050 <.050 <.050

07/15/03 1430 LD <.050 <.050 <.050 <.050

12/03/03 1400 R <.050 <.050 <.050 <.050

12/03/03 1401 FR <.050 <.050 <.050 <.050

12/03/03 1402 FB <.050 <.050 <.050 <.050

08/15/04 1930 R <.020 <.050 <.020 .002

08/15/04 1932 FCS .171 <.050 <.020 .012

08/30/04 1300 R <.020 <.050 <.020 <.020

08/30/04 1306 FB <.020 <.050 <.020 <.020

10/12/04 1230 R <.020 <.050 <.020 <.020

10/12/04 1232 FCS .112 <.050 <.020 .007

Texas

20 Beaver Creek near Electra 08/30/03 1305 R <.050 <.050 <.050 <.050

08/30/03 1306 FR <.050 <.050 <.050 <.050

Quality Assurance 17
Quality-assurance laboratory samples for the OGRL 

LC/MS chlorothalonil method consisted of 16 blank, 12 duplicate, and 14 spiked samples. The results for the laboratoryduplicate and field- and laboratory-spiked samples are shown 

in table 5. Chlorothalonil and its degradation products were 

not detected in any of the laboratory blank samples. The laboratory-duplicate samples were analyzed to estimate precision 

at ambient chlorothalonil concentrations in natural matrices. 

Field-spiked samples (FCS) were fortified at 0.25 μg/L with 

chlorothalonil. The concentration of chlorothalonil in these 

FCS varied from 0.11 to 0.25 μg/L.

Analysis of Chlorothalonil by Gas 

Chromatography/Mass Spectrometry

Analysis of chlorothalonil using GC/MS selected-ion 

monitoring demonstrated stable retention times, quantitation 

and confirming ions, and abundance percentage response as 

previously discussed. Samples fortified with a spike mixture 

containing chlorothalonil, which had been extracted in September 2003, were analyzed by the GC/MS method in March 

2004. Results in table 6 show that the recoveries of several 

samples spiked at 0.025 μg/L varied from 78 and 116 percent 

indicating good performance.

Analysis of Other Pesticides and Their 

Degradation Products

Surrogate compounds were added to all environmental and blank samples analyzed for pesticides by the USGS 

NWQL. Surrogate compounds in samples analyzed using 

laboratory schedule 2001 were diazinon-d10 and alpha 

HCH-d6. Three surrogates, barban, 2,4,5-T, and caffeine-C13, 

were added to samples analyzed using laboratory schedule 

2060. Surrogate compounds were similar in chemical properties to some target analytes but were not expected to be present 

in the environmental samples. They were used to assess 

extraction efficiency and to detect potential sample-processing 

problems in the laboratory.

A summary of surrogate compound recoveries for 

samples analyzed in 2003 and 2004 is shown in table 7. The 

surrogate standard recoveries in NWQL schedule 2001 ranged 

from 85 to 123 and 82 to 120 percent in 2003 and 2004, 

respectively. For the 2060 schedule, the surrogate standard 

recovery ranged from 66 to 134 and 4 to 151 percent in 2003 

and 2004, respectively. The smallest minimum recoveries 

were obtained from barban and 2,4,5-T at 4 and 30 percent, 

respectively. The median recovery for all the surrogate standards that could be calculated ranged from 75 to 110 percent 

indicating overall acceptable method performance.

Results of Analyses

In the “Supplemental Information” section at the back of 

this report, results of analyses of water samples from 22 surface-water sampling sites are shown in tables 12–17 by analytical method as previously described. Statistical summaries 

of reported concentrations are provided in tabular form in the 

following sections. For the calculation of the statistics in these 

tables, all nondetections were treated as zero.

Table 5. Concentrations of chlorothalonil and three chlorothalonil degradation products in quality-assurance samples from surfacewater sampling sites in five Southern States as determined by U.S. Geological Survey Organic Geochemistry Research Laboratory, 

Lawrence, Kansas, 2003–04.—Continued

[Sample type: FB, field blank; FCS, field chlorothalonil spike; FR, field replicate; LD, laboratory duplicate; LS, laboratory spike; R, regular environmental; 

<, less than; --, no data] 

Map

number

(fig. 1)

Site location

Date of

collection

(month/day/

year)

Collection time

(24-hour)

Sample

type

Concentrations, in micrograms per liter

Chlorothalonil

1-3,

diamidechlorothalonil

1 amide4-hydroxychlorothalonil

4-hydroxychlorothalonil

Texas—Continued

21 Sabana River near DeLeon 07/09/03 1240 R <0.050 <0.050 <0.050 <0.050

07/09/03 1240 LS 1.02 .950 1.48 --

09/03/03 1030 R <.050 <.050 <.050 <.050

09/03/03 1030 FB <.050 <.050 <.050 <.050

12/11/03 1130 R <.050 <.050 <.050 <.050

12/11/03 1130 LS .050 .810 .200 .560

18  Results of Analyses of the Fungicide Chlorothalonil, Its Degradation Products, and Other Selected Pesticides
Chlorothalonil and Its Degradation Products

The development of the LC/MS method by the USGS 

OGRL was critical to a better understanding of the occurrence 

and transport of chlorothalonil and its three principle degradation products, 4-hydroxy-chlorothalonil, 1,3-diamide-chlorothalonil, and 1-amide-4-hydroxy-chlorothalonil. Concentrations 

of chlorothalonil and three of its degradation products using 

LC/MS analysis are shown in table 12, and concentrations 

using GC/MS analysis by the USGS Methods and Research 

Development Group are shown in table 13 in the “Supplemental Information” section at the back of this report. A statistical summary of LC/MS and GC/MS chlorothalonil analytical 

results is shown in table 8. Chlorothalonil was detected in 

4 (4 percent) of the 113 water samples analyzed by LC/MS, 

with concentrations ranging from 0.089 to 0.433 μg/L. Of 

the 113 water samples analyzed by LC/MS, the chlorothalonil 

degradation product, 4-hydroxy-chlorothalonil, was detected 

in 26 of the samples with a 23-percent detection rate. This 

degradation product had a minimum detected concentration of 

0.002 μg/L and a maximum concentration of 0.930 μg/L. The 

remaining two chlorothalonil degradation products, 1-amide–

4-hydroxy-chlorothalonil and 1,3-diamide-chlorothalonil, had 

detections of 0.020 and 0.161 μg/L, respectively.

Chlorothalonil was detected in 5 (7 percent) of the 

68 sample extracts analyzed by GC/MS (table 8). Low levels 

of chlorothalonil at 0.01 μg/L were estimated from minimum 

area counts of the lowest calibration standard that could be 

reliably determined with all ions present in correct abundance. 

In many samples, a peak with the correct retention time for 

chlorothalonil (21.26 minutes) and the two most abundant ions 

(264 and 266 m/z) were present, but chlorothalonil could not 

Results of Analyses 19

Table 6. Percentage recoveries of chlorothalonil in extracts of reagent-water samples fortified at 0.025 microgram per liter, extracted 

by solid-phase extraction in July–August 2003, and analyzed by gas chromatography/mass spectrometry in March 2004. 

[μg/L, micrograms per liter]

Laboratory identification 

number

Collection date 

(month/day/year)

Collection time 

(24-hour)

Fortification level 

(μg/L)

Recovery

(percent)

20012430321 08/31/01 1605 0.025 115

20012430322 08/31/01 1600 .025 116

20012490116 09/06/01 1600 .025 109

20012490117 090/6/01 1605 .025 93

20012560174 09/13/01 1600 .025 85

20012560175 09/13/01 1605 .025 82

20012820104 10/09/01 1600 .025 78

20012820105 10/09/01 1605 .025 90

Table 7. Percentage recoveries of surrogate compounds in samples from 22 surface-water sampling sites in five Southern States 

using U.S. Geological Survey National Water-Quality Laboratory (Lakewood, Colorado) schedules 2001 and 2060, 2003–04.

[Values are percentage recovered. E, estimated; NA, not applicable]

Year Laboratory 

schedule

Surrogate 

compound

Number of 

samples

Percentage recoveries

Maximum Minimum Median

2003 2001 diazinon-d10 64 123 92 103

2001 alpha HCH-d6 64 111 85 96

2060 Barban 2 134 E82 NA

2060 2,4,5-T 2 104 66 NA

2060 caffeine-C13 2 E79 68 NA

2004 2001 diazinon-d10 20 120 94 110

2001 alpha HCH-d6 20 103 82 94

2060 Barban 19 105 E4 E75

2060 2,4,5-T 19 119 E30 E84

2060 caffeine-C13 19 E151 74 E105
be confirmed because the lower abundance confirming ions 

(124 and 229 m/z) were lacking.

Chlorothalonil was detected in only one of the samples 

(Pond Creek near Milton, July 29, 2003) analyzed by both the 

LC/MS and the GC/MS. Of the five samples where chlorothalonil was detected by the GC/MS method, four of the 

detections were less than the LRL of the LC/MS. The reasons 

for this discrepancy are not known. The low concentrations 

at which chlorothalonil and its degradation products were 

detected in surface water is demonstrated in table 8, which 

shows that none of the chorothalonil compounds were detected 

at concentrations greater than the LRLs at the 90th percentile 

of the chlorothalonil concentrations.

Other Selected Pesticides and Their 

Degradation Products

Concentrations of selected pesticides and their degradation products analyzed as part of NWQL schedules 2001 

and 2060 and detected in one or more samples are shown 

in tables 14 and 15, respectively, in the “Supplemental 

Information” section. A statistical summary for both NWQL 

schedules is shown in table 9. Although LRLs ranged from 

0.003 to 0.050 μg/L for NWQL schedule 2001 and 0.008 to 

0.040 μg/L for NWQL schedule 2060 (table 4), compound 

concentrations were estimated as low as 0.001 μg/L depending 

on the sample matrix (table 9).

Eighty-four water samples were analyzed by NWQL 

schedule 2001 (table 9). Twenty-one of the 52 parent pesticides and pesticide degradation products were detected at or 

above their LRL (see table 4). Metolachlor, the most 

frequently detected pesticide, was present in 58 percent of the 

samples, followed by atrazine (50 percent), and deethylatrazine (27 percent), which is a degradation product of atrazine.

NWQL schedule 2060 (table 4) contains 62 parent pesticides and pesticide degradation products. Eighteen compounds were detected at or above LRLs (table 9). 

2-hydroxyatrazine, a triazine degradation product, and caffeine 

were detected in 48 percent of the samples, whereas atrazine, 

bentazon, diuron, and tebuthiron were all detected in 29 percent of the samples. Chlorothalonil had two estimated detections 0.061 and 0.161 μg/L. Fenuron also had two detections 

(9.5 percent) and contained the highest reported concentration 

at 1.51 μg/L of all compounds analyzed using NWQL schedule 2060.

Dissolved Organic Carbon and Suspended 

Sediment

Results for dissolved organic carbon concentrations, 

suspended-sediment concentrations, and percentage of 

silt- and clay-sized particles are presented in table 16 in the 

“Supplemental Information” section at the back of this report, 

and a statistical summary is shown in table 10. Dissolved 

organic carbon concentrations ranged from 1.2 to 41 mg/L 

(table 16). Suspended-sediment concentrations ranged from 

3 to 1,329 mg/L, and percentage of silt- and clay-sized particles ranged from 21 to 98 percent in the suspended-sediment 

samples.

Table 8. Statistical summary of concentrations of chlorothalonil and three chlorothalonil degradation products determined by liquid 

chromatography/mass spectrometry (U.S. Geological Survey Organic Geochemistry Research Laboratory, Lawrence, Kansas) and gas 

chromatography/mass spectrometry (U.S. Geological Survey Methods and Research Development Group, Lakewood, Colorado) for 

water samples collected from 22 sampling sites in five Southern States, 2003–04.

[<LRL, less than laboratory reporting level; NA, not applicable]

Compound

Number 

of

samples

Number of

samples at or 

above

laboratory reporting levels

Concentrations (micrograms per liter)

Mean Median 90th

percentile Maximum Minimum

Liquid chromatography/mass spectrometry (LRL = 0.020 and 0.050 microgram per liter)

Chlorothalonil 113 4 0.150 0.135 <LRL 0.433 0.089

1,3-diamide of 

chlorothalonil

113 1 NA NA NA .161 NA

1 amide-4-hydroxy of 

chlorothalonil 

113 1 NA NA NA .020 NA

4-hydroxy of 

chlorothalonil

113 26 <LRL <LRL <LRL .930 .002

Gas chromatography/mass spectrometry (LRL = 0.01 microgram per liter)

Chlorothalonil 68 5 .001 LRL LRL .035 .004

20 Results of Analyses of the Fungicide Chlorothalonil, Its Degradation Products, and Other Selected Pesticides
Results of Analyses 21

Table 9. Statistical summary of concentrations of selected pesticides and pesticide degradation products determined by U.S. 

Geological Survey National Water-Quality Laboratory (Lakewood, Colorado) schedules 2001 and 2060 for water samples collected 

from 22 surface-water sampling sites in five Southern States, 2003–04.

[E, estimated; LD, less than method detection level; <LRL, less than laboratory reporting level; <, less than]

Herbicide Number of

samples

Percentage of 

samples at or 

above

 laboratory 

reporting level

Concentrations (micrograms per liter)

Mean Median 90th percentile Maximum Minimum

Schedule 2001

Alachlor 84 9.5 0.001 <LRL LD 0.041 0.010

Atrazine 84 50 .019 .002E .028 .505 .008

Carbaryl 84 3.6 .001 <LRL LD .027E .006E

Carbofuran 84 1.2 <.001 <LRL LD .006E .006E

Chlorpyrifos 84 6.0 .001 <LRL LD .018 .008

Cyanazine 84 2.4 <.001 <LRL LD .011E .008E

Deethylatrazine 84 27 .003 <LRL .009 .050 .003E

Diazinon 84 1.2 <.001 <LRL LD .011 .011

Ethalfluralin 84 3.6 <.001 <LRL LD .022 .009

Malathion 84 3.6 .001 <LRL LD .033 .033

Metolachlor 84 58 .008 .006 .019 .063 .013

Metribuzin 84 7.1 .001 <LRL LD .046 .009

Parathion 84 1.2 <.001 <LRL LD .007E .007E

Pendimethalin 84 3.6 .001 <LRL LD .040 .040

Prometon 84 16 .002 <LRL .005 .031 .005E

Propanil 84 1.2 <.001 <LRL LD .003E .003E

Propargite 84 6.0 .013 <LRL LD .032 .007E

Simazine 84 12 .003 <LRL .006 .117 .006

Terbuthiuron 84 13 .002 <LRL .007 .022 .018

Terbacil 84 1.2 <.001 <LRL LD .008E .008E

Trifluralin 84 3.6 <.001 <LRL LD .013 .008E

Schedule 2060

2,4-D 21 24 0.009 <LRL 0.037 0.056 0.026

2-Hydroxyatrazine 21 48 .024E <LRL .054 .143 .009E

Acifluorfen 21 4.8 .001 <LRL LD .029 .029

Atrazine 21 29 .005 <LRL .014 .031 .005E

Bensulfuron-methyl 21 4.8 <.001 <LRL LD .006E .006E

Bentazon 21 29 .019 <LRL .026 .280 .007E

Caffeine 21 48 .021 <LRL .037 .125 .014E

Chlorothalonil 21 9.5 .011 <LRL LD .161 .061

Deisopropylatrazine 21 4.8 <.001 <LRL LD .007E .007E
Associated Streamflow and Physical Properties

The streamflow discharge measurements, gage heights, 

and physical properties associated with each surface-water 

sample were recorded at all sites during the 2003–04 sampling 

and are listed in table 17 in the “Supplemental Information” 

section at the back of this report. A statistical summary of 

these data is shown in table 11.

Conclusions

Chlorothalonil is a fungicide that has been used in the 

United States for more than 30 years. It has a wide range of 

uses, including agricultural, home, garden, and industrial. 

The greatest use of chlorothalonil is on peanuts in the States 

of Alabama, Florida, and Georgia. The field half-life for 

chlorothalonil ranges from 10 to 60 days and this, coupled 

with large application amounts and the practice of frequent, 

repeated applications, could promote the offsite movement of 

this fungicide. Because chlorothalonil has the potential to be 

transported away from the point of application through spray 

drift, field runoff, or unsaturated zone transport, it has been 

detected in surface water, rainfall, and air samples, whereas 

chlorothalonil degradation products have been detected in 

ground-water samples. Chlorothalonil also has been classified 

as a probable carcinogen by the U.S. Environmental Protection 

Agency as tests have shown very high toxicity to both fish and 

aquatic invertebrates.

This report documents the results of analyses of chlorothalonil and its degradation products in surface water in five 

Southern States—Alabama, Florida, Georgia, Oklahoma, and 

Texas. In 2003, sampling was conducted at 22 surface-water 

sites located in the five States. Samples were collected during 

three sampling periods extending through the peanut-growing season (June–September), with the exception of one site 

each in Oklahoma and Texas, which were sampled twice. In 

2004, sampling was a modified version of the 2003 sampling 

in which water samples were collected at 9 of the 22 surfacewater sampling sites in three States (Alabama, Florida, and 

Georgia) within 48 hours after storms.

An analytical method, using solid-phase extraction (SPE) 

and liquid chromatography/mass spectrometry (LC/MS), to 

determine chlorothalonil and three degradation products was 

developed by the U.S. Geological Survey’s (USGS) Organic 

Geochemistry Research Laboratory (OGRL) in Lawrence, 

Kansas. The development of the LC/MS method was critical to a better understanding of the occurrence and transport 

of chlorothalonil and its three principle degradation products, 

4-hydroxy-chlorothalonil, 1,3-diamide-chlorothalonil, and 

1-amide-4-hydroxy-chlorothalonil. Of the 113 water samples 

analyzed by LC/MS, chlorothalonil was detected in one 

sample during 2003 and three samples during 2004 from water 

collected at sites in Alabama, Florida, and Georgia. Concentrations ranged from 0.089 to 0.433 μg/L. The primary 

degradation product, 4-hydroxy-chlorothalonil, was reported 

in 26 samples during 2003–04 with a concentration range of 

0.002 to 0.930 μg/L. The degradation product 1-amide-4-

hydroxy-chlorothalonil was detected in one sample at a conTable 9. Statistical summary of concentrations of selected pesticides and pesticide degradation products determined by U.S. 

Geological Survey National Water-Quality Laboratory (Lakewood, Colorado) schedules 2001 and 2060 for water samples collected 

from 22 surface-water sampling sites in five Southern States, 2003–04.—Continued

[E, estimated; LD, less than method detection level; <LRL, less than laboratory reporting level; <, less than]

Herbicide Number of

samples

Percentage of 

samples at or 

above

 laboratory 

reporting level

Concentrations (micrograms per liter)

Mean Median 90th percentile Maximum Minimum

Schedule 2060—Continued

Dinoseb 21 9.5 0.005 <LRL LD 0.087 0.008E

Diuron 21 29 .052 <LRL .151 .685 .017

Fenuron 21 9.5 .073 <LRL LD 1.5 .016E

Fluometuron 21 14 .002 <LRL .009 .022 .009E

Norflurazon 21 10 <.001 <LRL LD .008E .008E

Oryzalin 21 19 .016 <LRL .048 .127 .043

Propiconazole 21 10 .002 <LRL LD .026 .005E

Tebuthiuron 21 29 .009 <LRL .023 .090 .005E

Triclopyr 21 14 .033 <LRL .093 .355 .093

22 Results of Analyses of the Fungicide Chlorothalonil, Its Degradation Products, and Other Selected Pesticides
centration of 0.020 μg/L, whereas 1,3-diamide-chlorothalonil 

was detected in one sample at a concentration of 0.161 μg/L.

The USGS Methods and Research Development Group 

developed a method for analysis of chlorothalonil by gas 

chromatography/mass spectrometry (GC/MS) in an effort 

to achieve a lower laboratory reporting level (LRL) than the 

USGS National Water-Quality Laboratory (NWQL) schedule 

2060 which contains the compound chlorothalonil at a LRL 

of 0.035 μg/L. The group succeeded in achieving a lower 

GC/MS LRL of 0.01 μg/L. Chlorothalonil was detected in 

5 of 68 water samples analyzed by the custom GC/MS method 

with a concentration range of 0.004 to 0.035 μg/L, whereas 

chlorothalonil was detected in 2 of 21 water samples analyzed 

by NWQL schedule 2060 with estimated concentrations of 

0.061 and 0.161 μg/L. The GC/MS analytical method demonstrated stable retention times, quantitation, and abundance 

percentage response.

As expected, chlorothalonil was detected only infrequently and at relatively low concentrations. Notably, 

chlorothalonil’s major degradation product, 4-hydroxy-chlorothalonil, was detected most frequently and occurred generally 

at higher concentrations in water samples than did the parent 

fungicide. Analytical results showed that the methods were 

valuable for acquiring information about the occurrence of the 

fungicide chlorothalonil. The data also reaffirm that 

4-hydroxy-chlorothalonil is the dominant degradation product 

in the peanut-growing environment as noted in previous 

studies.

References Cited

Aiken, G.R., 1992, Chloride interference in the analysis of 

dissolved organic carbon by the wet oxidation method: 

Environmental Science & Technology, v. 26, p. 2435–2439.

Aiken, G.R., McKnight, D.M., Thorn, K.A., and Thurman, 

E.M., 1992, Isolation of hydrophilic acids from water using 

macroporous resins: Organic Geochemistry, v. 18, p. 567–

573.

Buchanan, T.J., and Somers, W.P., 1969, Discharge measurements at gaging stations: U.S. Geological Survey Techniques of Water-Resources Investigations, book 3, chaps. 

A7 and A8, various pagination.

References Cited 23

Table 10. Statistical summary of concentrations of dissolved organic carbon, suspended sediment, and percentage of silt- and claysized particles for water samples collected from 22 surface-water sampling sites in five Southern States, 2003–04. 

[mg/L, milligrams per liter; <, less than; mm, milligrams]

Herbicide Number of

samples

Percentage of

samples at or 

above

 laboratory reporting levels

Concentrations or percentage

Mean Median 90th

percentile Maximum Minimum

Dissolved organic carbon, in mg/L 92 100 11 7.9 20 41 1.2

Suspended sediment, in mg/L 74 100 54 16 42 1,329 3

Silt- and clay-sized particles 

(<0.062 mm), in percent 

70 100 71 74 93 98 28

Table 11. Statistical summary of streamflow and physical properties determined for water samples collected from 22 surface-water 

sampling sites in five Southern States, 2003–04.

Streamflow or physical property

Number 

of

samples

Percentage of 

samples at or 

above

laboratory 

reporting level

Measurement

Mean Median 90th

percentile Maximum Minimum

Instantaneous discharge, in cubic feet per 

second

98 100 186 37.1 811 2,329 1.3

Specific conductance, in microsiemens per 

centimeter at 25 degrees Celsius

97 100 240 69 580 3,760 22

pH, in standard units 97 100 6.4 6.4 7.8 8.2 4.4

Water temperature, in degrees Celsius 46 100 24.2 24.2 25.9 32.5 16.2

Dissolved oxygen, in milligrams per liter 46 100 5.8 5.7 8.5 11 1.5
Chernyak, S.M., Rice, C.P., and McConnell, L.L., 1996, Evidence of currently-used pesticides in air, ice, fog, seawater 

and surface microlayer in the Bering and Chukchi Seas: 

Marine Pollution Bulletin, v. 32, no. 5, p. 410–419.

Cox, Caroline, 1997, Fungicide fact sheet—chlorothalonil: 

Journal of Pesticide Reform, v. 17, no. 4, p. 14–20.

Furlong, E.T., Anderson, B.D., Werner, S.L., Soliven, P.P., 

Coffey, L.J., and Burkhardt, M.R., 2001, Methods of 

analysis by the U.S. Geological Survey National Water 

Quality Laboratory—determination of pesticides in water 

by graphitized carbon-based solid-phase extraction and 

high-performance liquid chromatography/mass spectrometry: U.S. Geological Survey Water-Resources Investigations 

Report 01–4134, 73 p.

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

analysis: U.S. Geological Survey Techniques of WaterResources Investigations, book 5, chap. C1, 58 p.

Harris, D., and Andreoli, A., 1988, Status report, pesticide 

sampling program 1980–1987: Suffolk County, New York, 

Bureau of Drinking Water, Suffolk County Department of 

Health Services, 23 p.

Katayama, A., Ukai, T., Nomura, K., and Kuwatsuka, S., 1992, 

Formation of a methylthioated metabolite from the fungicide chlorothalonil by soil bacteria; Bioscience Biotechnical 

Biochemistry, v. 56, no. 9, p. 1520–1521.

Madsen, J.E., Sandstrom, M.W., and Zaugg, S.D., 2003, 

Methods of analysis by the U.S. Geological Survey National 

Water Quality Laboratory—a method supplement for the 

determination of fipronil and degradates in water by gas 

chromatography/mass spectrometry: U.S. Geological Survey Open-File Report 02–462, 11 p.

McConnell, L.L., LeNoir, J.S., Datta, S., and Seiber, J.N., 

1998, Wet deposition of current-use pesticides in the Sierra 

Nevada mountain range, California, USA: Environmental 

Toxicology and Chemistry, v. 17, no. 10, p. 1908–1916.

National Center for Food and Agricultural Policy, 1997, 

National pesticide use database: Washington, D.C., information available on the Web, accessed April 20, 2006, at 

http://www.ncfap.org/database/default.php

Potter, T.L., Wauchope, R.D., and Culbreath, A.K., 2001, 

Accumulation and decay of chlorothalonil and selected 

metabolites in surface soil following foliar application 

to peanuts: Environmental Science & Technology, v. 35, 

p. 2634–2639.

Rouchaud, Jean, Roucourt, Pascal, Vanazhter, Alfons, Benoit, 

Frans, and Ceustermans, Norbert, 1988, Hydrolytic biodegradation of chlorothalonil in soil and in cabbage crops: 

Toxicology and Environmental Chemistry, v. 17, p. 59–68.

Sakai, Manabu, 2002, Determination of pesticides and chronic 

test with daphnia magna for rainwater samples: Journal of 

Environmental Science Health, v. B37, no. 3, p. 247–254.

Sakkas, V.A., Lambropoulou, D.A., and Albanis, T.A., 2002, 

Study of chlorothalonil photodegradation in natural waters 

and in the presence of humic substances: Chemosphere, 

v. 48, p. 939–945.

Sandstrom, M.W., Stroppel, M.W., Foreman, W.T., and Schroeder, M.P., 2001, Methods of analysis by the U.S. Geological Survey National Water Quality Laboratory—determination of moderate-use pesticides and selected degradates in 

water by C-18 solid-phase extraction and gas chromatography/mass spectrometry: U.S. Geological Survey WaterResources Investigations Report 01–4098, 70 p.

Sato, K., and Tanaka, H., 1987, Degradation and metabolism 

of a fungicide, 2,4,5,6-tetrachloroisophthalonitrile (TPN) in 

soil: Biology Fertilizer Soils, v. 3, p. 205–209.

Scott, G.I., Fulton, M.H., Wirth, E.F., Chandler, G.T., Key, 

P.B., Daughomah, J.W., Bearden, D., Chung, K.W., Strozier, 

E.D., DeLorenzo, M., Sivertsen, S., Dias, A., Sanders, M., 

Macauley, J.M., Goodman, L.R., LaCroix, M.W., Thayer, 

G.W., and Kucklick, J., 2002, Toxicological studies in tropical ecosystems—an ecotoxicological risk assessment of pesticide runoff in South Florida estuarine ecosystems: Journal 

of Agriculture and Food Chemistry, v. 50, p. 4400–4408.

Shelton, L.R., 1994, Field guide for collecting and processing stream-water samples for the National Water-Quality 

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

Report 94–455, 50 p.

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

and processing samples of stream bed sediment for analysis 

of trace elements and organic contaminants for the National 

Water-Quality Assessment Program: U.S. Geological Survey Open-File Report 94–458, 20 p.

Syngenta Crop Protection, 2005, Chlorothalonil 

ENVIROfacts: Information available on Web, accessed 

December 19, 2005, at 

http://www.syngentacropprotection.com/enviro/futuretopics/

U.S. Environmental Protection Agency, 1999, EPA reregistration eligibility decision (RED) chlorothalonil: 

EPA 738–R–99–004, available on Web, accessed June 26, 

2006, at http://www.epa.gov/REDs/0097red/pdf

U.S. Geological Survey, 2005, Sediment Laboratory quality assurance project data: Information available on Web, 

accessed February 28, 2005, at http://sedserv.cr.usgs.gov/

Lab results/ca.htm

24 Results of Analyses of the Fungicide Chlorothalonil, Its Degradation Products, and Other Selected Pesticides
Wilde, F.D., Radke, D.B., Gibs, J., and Iwatsubo, R.T., eds., 

1999, Collection of water samples, in National field manual 

for the collection of water quality data: U.S. Geological 

Survey Techniques of Water-Resources Investigations, 

book 9, chap. A4, p. 7–48.

Zaugg, S.D., Sandstrom, M.W., Smith, S.G., and Fehlberg, 

K.M., 1995, Methods of analysis by the U.S. Geological 

Survey National Water Quality Laboratory—determination 

of pesticides in water by C-18 solid-phase extraction and 

capillary-column gas chromatography/mass spectrometry 

with selected-ion monitoring: U.S. Geological Survey 

Open-File Report 95–181, 60 p.

References Cited 25
26  Results of Analyses of the Fungicide Chlorothalonil, Its Degradation Products, and Other Selected Pesticides
Supplemental Information

Supplemental Information 27
Table 12. Concentrations of chlorothalonil and three chlorothalonil degradation products analyzed by the U.S. Geological Survey 

Organic Geochemistry Research Laboratory, Lawrence, Kansas, for water samples collected from 22 surface-water sampling sites in 

five Southern States, 2003–04. 

[ND, no detection; Sample type: R, regular environmental; <, less than; --, no data]

Map

number

(fig. 1)

Site name

Date of

collection

(month/day

year)

Collection

time

(24-hour)

Sample

type

Concentrations, in micrograms per liter

Chlorothalonil4-hydroxychlorothalonil

1,3-

diamidechlorothalonil

1-amide4-hydroxychlorothalonil

Alabama

1 Big Creek at State Highway 203 

near Rehobeth

06/25/03 1220 R <0.050 <0.050 <0.050 <0.050

08/06/03 1140 R <.050 <.050 <.050 <.050

09/17/03 1220 R <.050 <.050 <.050 <.050

2 Cedar Creek at East Cook Road 

near Pansey

06/26/03 1210 R <.050 <.050 <.050 <.050

08/04/03 1105 R <.050 .110 <.050 <.050

09/15/03 1545 R <.050 <.050 <.050 <.050

06/15/04 1250 R <.020 .066 <.050 .020

09/17/04 1220 R <.020 .136 <.050 <.020

3 Cowarts Creek above 

Cottonwood

06/26/03 1515 R <.050 <.050 <.050 <.050

08/05/03 0900 R <.050 <.050 <.050 <.050

09/16/03 1225 R <.050 <.050 <.050 <.050

4 Cowarts Creek near Love Hill 06/25/03 1730 R <.050 <.050 <.050 <.050

08/05/03 1300 R <.050 <.050 <.050 <.050

09/16/03 1550 R <.050 <.050 <.050 <.050

5 Spring Creek at County Road 55 

near Geneva

06/25/03 0810 R <.050 <.050 <.050 <.050

08/06/03 0810 R <.050 <.050 <.050 <.050

09/17/03 0900 R <.050 <.050 <.050 <.050

Florida

6 Moore Creek near Chumuckla 06/23/03 1125 R <0.050 <0.050 <0.050 <0.050

07/29/03 1225 R <.050 <.050 <.050 <.050

09/25/03 1200 R <.050 <.050 <.050 <.050

7 Pond Creek near Milton 06/23/03 1500 R <.050 <.050 <.050 <.050

07/29/03 1435 R .120 <.050 <.050 <.050

09/24/03 1400 R <.050 <.050 <.050 <.050

06/14/04 1310 R <.020 <.020 <.050 <.020

09/23/04 0830 R <.020 .007 <.050 <.020

09/23/04 0830 R <.020 .008 <.050 <.020

28  Results of Analyses of the Fungicide Chlorothalonil, Its Degradation Products, and Other Selected Pesticides
Table 12. Concentrations of chlorothalonil and three chlorothalonil degradation products analyzed by the U.S. Geological Survey 

Organic Geochemistry Research Laboratory, Lawrence, Kansas, for water samples collected from 22 surface-water sampling sites in 

five Southern States, 2003–04.—Continued

[ND, no detection; Sample type: R, regular environmental; <, less than; --, no data]

Map

number

(fig. 1)

Site name

Date of

collection

(month/day

year)

Collection

time

(24-hour)

Sample

type

Concentrations, in micrograms per liter

Chlorothalonil4-hydroxychlorothalonil

1,3-

diamidechlorothalonil

1-amide4-hydroxychlorothalonil

Florida—Continued

8 Russ Mill Creek at Union Road 

near Cottondale

06/24/03 1330 R <0.050 <0.050 <0.050 <0.050

08/05/03 1640 R <.050 <.050 <.050 <.050

09/16/03 0825 R <.050 <.050 <.050 <.050

9 West Fork Big Coldwater Creek 

near Allentown

06/24/03 0900 R <.050 <.050 <.050 <.050

07/30/03 0800 R <.050 <.050 <.050 <.050

09/25/03 0845 R <.050 <.050 <.050 <.050

Georgia

10 Big Creek at Crystal Lake Road 

near Irwinville

07/16/03 1340 R <.050 <.050 <.050 <.050

08/13/03 0710 R <.050 <.050 <.050 <.050

09/24/03 0715 R <.050 <.050 <.050 <.050

11 Black Creek near Blichton 07/14/03 1020 R <.050 <.050 <.050 <.050

08/11/03 0945 R <.050 <.050 <.050 <.050

09/08/03 0900 R <.050 <.050 <.050 <.050

09/08/03 0915 R <.050 <.050 <.050 <.050

09/08/03 0930 R <.050 <.050 <.050 <.050

09/08/03 0945 R <.050 <.050 <.050 <.050

09/08/03 1000 R <.050 <.050 <.050 <.050

09/08/03 1015 R <.050 <.050 <.050 <.050

09/08/03 1030 R <.050 <.050 <.050 <.050

09/08/03 1045 R <.050 <.050 <.050 <.050

09/08/03 1100 R <.050 <.050 <.050 <.050

09/08/03 1115 R <.050 <.050 <.050 <.050

09/08/03 1130 R <.050 <.050 <.050 <.050

09/08/03 1145 R <.050 <.050 <.050 <.050

09/22/03 1230 R <.050 <.050 <.050 <.050

10/18/03 1820 R <.050 <.050 <.050 <.050

10/18/03 1850 R <.050 <.050 <.050 <.050

10/18/03 1920 R <.050 <.050 <.050 <.050

Supplemental Information 29
Table 12. Concentrations of chlorothalonil and three chlorothalonil degradation products analyzed by the U.S. Geological Survey 

Organic Geochemistry Research Laboratory, Lawrence, Kansas, for water samples collected from 22 surface-water sampling sites in 

five Southern States, 2003–04.—Continued

[ND, no detection; Sample type: R, regular environmental; <, less than; --, no data]

Map

number

(fig. 1)

Site name

Date of

collection

(month/day

year)

Collection

time

(24-hour)

Sample

type

Concentrations, in micrograms per liter

Chlorothalonil4-hydroxychlorothalonil

1,3-

diamidechlorothalonil

1-amide4-hydroxychlorothalonil

Georgia—Continued

11 Black Creek near Blichton—

Continued

10/18/03 1950 R <0.050 <0.050 <0.050 <0.050

10/18/03 2030 R <.050 <.050 <.050 <.050

06/23/04 0430 R <.020 .009 <.050 <.020

06/23/04 0630 R <.020 .009 <.050 <.020

06/23/04 0730 R <.020 .011 <.050 <.020

06/23/04 0830 R <.020 .014 <.050 <.020

06/23/04 0930 R <.020 .008 <.050 <.020

06/24/04 0915 R <.020 .013 <.050 <.020

09/06/04 0940 R <.020 <.020 <.050 <.020

09/06/04 2140 R <.020 .010 <.050 <.020

09/07/04 0340 R <.020 <.020 <.050 <.020

09/07/04 0940 R <.020 <.020 <.050 <.020

09/07/04 1540 R <.020 <.020 <.050 <.020

12 Bridge Creek at James King Road 

near Doerun 

07/15/03 1150 R <.050 <.050 <.050 <.050

08/12/03 1000 R <.050 .120 <.050 <.050

09/23/03 0800 R <.050 <.050 <.050 <.050

07/08/04 1900 R <.020 .019 <.020 <.020

09/06/04 1346 R .089 .008 <.020 <.020

13 Coheelee Creek at River Road 

near Hilton

06/26/03 0815 R <.050 <.050 <.050 <.050

08/04/03 1435 R <.050 <.050 <.050 <.050

09/15/03 1220 R <.050 <.050 <.050 <.050

06/15/04 1510 R <.020 .031 <.050 <.020

09/17/04 1530 R <.020 .174 <.050 <.020

14 Little Abrams Creek at GA 

Highway 313 near Doles

07/15/03 1500 R <.050 .190 <.050 <.050

08/12/03 1245 R <.050 .850 <.050 <.050

08/12/03 1300 R <.050 <.050 <.050 <.050

09/23/03 1350 R <.050 <.050 <.050 <.050

07/08/04 1030 R .433 .930 <.050 <.020

07/08/04 1215 R .150 .350 <.050 <.020

30 Results of Analyses of the Fungicide Chlorothalonil, Its Degradation Products, and Other Selected Pesticides
Table 12. Concentrations of chlorothalonil and three chlorothalonil degradation products analyzed by the U.S. Geological Survey 

Organic Geochemistry Research Laboratory, Lawrence, Kansas, for water samples collected from 22 surface-water sampling sites in 

five Southern States, 2003–04.—Continued

[ND, no detection; Sample type: R, regular environmental; <, less than; --, no data]

Map

number

(fig. 1)

Site name

Date of

collection

(month/day

year)

Collection

time

(24-hour)

Sample

type

Concentrations, in micrograms per liter

Chlorothalonil4-hydroxychlorothalonil

1,3-

diamidechlorothalonil

1-amide4-hydroxychlorothalonil

Georgia—Continued

15 Reedy Creek at U.S. Highway 

129 near Ocilla

07/16/03 0745 R <0.050 <0.050 <0.050 <0.050

08/13/03 1345 R <.050 <.050 <.050 <.050

09/24/03 1340 R <.050 <.050 <.050 <.050

16 Warrior Creek near Sumner 07/15/03 0750 R <.050 <.050 <.050 <.050

08/12/03 0715 R <.050 <.050 <.050 <.050

09/23/03 1020 R <.050 <.050 <.050 <.050

07/08/04 1410 R <.020 .022 <.050 <.020

07/08/04 1530 R <.020 .281 .161 <.020

17 Willacoochee Creek at Frank 

Road near Ocilla

07/16/03 1100 R <.050 <.050 <.050 <.050

08/13/03 0930 R <.050 <.050 <.050 <.050

09/24/03 1000 R <.050 <.050 <.050 <.050

Oklahoma

18 Cobb Creek near Eakly 07/15/03 1030 R <.050 <.050 <.050 <.050

07/30/03 1200 R <.050 <.050 <.050 <.050

12/03/03 1015 R <.050 <.050 <.050 <.050

08/15/04 1630 R <.020 .002 <.050 <.020

08/28/04 1700 R <.020 .018 <.050 <.020

10/07/04 2130 R <.020 <.020 <.050 <.020

19 Cobb Creek near Fort Cobb 07/17/03 1430 R <.050 <.050 <.050 <.050

12/03/03 1400 R <.050 <.050 <.050 <.050

08/15/04 1930 R <.020 .002 <.050 <.020

08/30/04 1300 R <.020 <.020 <.050 <.020

10/12/04 1230 R <.020 <.020 <.050 <.020

Texas

20 Beaver Creek near Electra 07/14/03 1255 R <.050 <.050 <.050 <.050

07/18/03 1415 R <.050 <.050 <.050 <.050

08/30/03 1305 R <.050 <.050 <.050 <.050

21 Sabana River near DeLeon 07/09/03 1240 R <.050 <.050 <.050 <.050

09/03/03 1030 R <.050 <.050 <.050 <.050

12/11/03 1130 R <.050 <.050 <.050 <.050

Supplemental Information 31
Table 12. Concentrations of chlorothalonil and three chlorothalonil degradation products analyzed by the U.S. Geological Survey 

Organic Geochemistry Research Laboratory, Lawrence, Kansas, for water samples collected from 22 surface-water sampling sites in 

five Southern States, 2003–04.—Continued

[ND, no detection; Sample type: R, regular environmental; <, less than; --, no data]

Map

number

(fig. 1)

Site name

Date of

collection

(month/day

year)

Collection

time

(24-hour)

Sample

type

Concentrations, in micrograms per liter

Chlorothalonil4-hydroxychlorothalonil

1,3-

diamidechlorothalonil

1-amide4-hydroxychlorothalonil

Texas—Continued

22 San Miguel Creek near Tilden 07/15/03 1050 R <0.050 <0.050 <0.050 <0.050

07/17/03 0910 R <.050 <.050 <.050 <.050

09/04/03 1100 R <.050 <.050 <.050 <.050

32 Results of Analyses of the Fungicide Chlorothalonil, Its Degradation Products, and Other Selected Pesticides
Table 13. Concentrations of chlorothalonil analyzed by the U.S. Geological Survey Methods and Research Development Group, 

Lakewood, Colorado, for water samples collected from 22 surface-water sampling sites in five Southern States, July through 

September 2003. 

[Sample type: B, blank; FR, field replicate; R, regular environmental; E, estimated; <, less than]

Map

number

(fig. 1)

Site name

Date of

collection

(month/day/

year)

Collection

time

(24-hour)

Sample

type

Concentration

of

chlorothalonil

(micrograms

per liter)

Alabama

1 Big Creek at State Highway 203 near Rehobeth 06/25/03 1220 R <0.01

08/06/03 1140 R <.01

09/17/03 1220 R <.01

2 Cedar Creek at East Cook Road near Pansey 06/26/03 1210 R <.01

08/04/03 1105 R <.01

09/15/03 1545 R <.01

3 Cowarts Creek above Cottonwood 06/26/03 1515 R <.01

08/05/03 0900 R <.01

09/16/03 1225 R <.01

4 Cowarts Creek near Love Hill 06/25/03 1730 R <.01

08/05/03 1300 R <.01

09/16/03 1550 R <.01

5 Spring Creek at County Road 55 near Geneva 06/25/03 0810 R <.01

08/06/03 0810 R <.01

09/17/03 0900 R <.01

Florida

6 Moore Creek near Chumuckla 06/23/03 1125 R <.01

07/29/03 1145 B <.01

07/29/03 1215 R <.01

7 Pond Creek near Milton 06/23/03 1500 R <.01

06/23/03 1501 FR <.01

07/29/03 1435 R E.007

09/24/03 1400 R <.01

8 Russ Mill Creek at Union Road near Cottondale 06/24/03 1330 R <.01

08/05/03 1640 R <.01

09/16/03 0825 R <.01

Supplemental Information 33
Table 13. Concentrations of chlorothalonil analyzed by the U.S. Geological Survey Methods and Research Development Group, 

Lakewood, Colorado, for water samples collected from 22 surface-water sampling sites in five Southern States, July through 

September 2003.—Continued

[Sample type: B, blank; FR, field replicate; R, regular environmental; E, estimated; <, less than]

Map

number

(fig. 1)

Site name

Date of

collection

(month/day/

year)

Collection

time

(24-hour)

Sample

type

Concentration

of

chlorothalonil

(micrograms

per liter)

Florida—Continued

9 West Fork Big Coldwater Creek near Allentown 06/24/03 0745 B <0.01

06/24/03 0900 R <.01

07/30/03 0800 R <.01

Georgia

10 Big Creek at Crystal Lake Road near Irwinville 07/16/03 1340 R <.01

08/13/03 0710 R <.01

09/24/03 0715 R <.01

11 Black Creek near Blichton 07/14/03 1020 R <.01

08/11/03 0945 R <.01

09/22/03 1230 R <.01

12 Bridge Creek at James King Road near Doerun 07/15/03 1150 R <.01

08/12/03 1000 R <.01

09/23/03 0800 R <.01

09/23/03 0801 B <.01

13 Coheelee Creek at River Road near Hilton 06/26/03 0815 R E.004

08/04/03 1435 R E.006

09/15/03 1220 R <.01

14 Little Abrams Creek at GA Highway 313 near Doles 07/15/03 1500 R <.01

08/12/03 1245 B <.01

08/12/03 1300 R .035

09/23/03 1350 R <.01

15 Reedy Creek at U.S. Highway 129 near Ocilla 07/16/03 0745 R <.01

08/13/03 1345 R <.01

09/24/03 1340 R <.01

16 Warrior Creek near Sumner 07/15/03 0745 B <.01

07/15/03 0750 R <.01

08/12/03 0715 R E.005

09/23/03 1020 R <.01

34 Results of Analyses of the Fungicide Chlorothalonil, Its Degradation Products, and Other Selected Pesticides
Table 13. Concentrations of chlorothalonil analyzed by the U.S. Geological Survey Methods and Research Development Group, 

Lakewood, Colorado, for water samples collected from 22 surface-water sampling sites in five Southern States, July through 

September 2003.—Continued

[Sample type: B, blank; FR, field replicate; R, regular environmental; E, estimated; <, less than]

Map

number

(fig. 1)

Site name

Date of

collection

(month/day/

year)

Collection

time

(24-hour)

Sample

type

Concentration

of

chlorothalonil

(micrograms

per liter)

Georgia—Continued

17 Willacoochee Creek at Frank Road near Ocilla 07/16/03 1100 R <0.01

08/13/03 0930 R <.01

09/24/03 1000 R <.01

Oklahoma

18 Cobb Creek near Eakly 07/15/03 1030 R <.01

07/15/03 1033 B <.01

07/30/03 1200 R <.01

19 Cobb Creek near Fort Cobb 07/15/03 1430 R <.01

Texas

20 Beaver Creek near Electra 07/18/03 1415 R <.01

08/30/03 1305 R <.01

21 Sabana River near DeLeon 07/09/03 1240 R <.01

09/03/03 1030 R <.01

09/03/03 1030 R <.01

12/11/03 1130 R <.01

22 San Miguel Creek near Tilden 07/15/03 1050 R <.01

07/17/03 0910 R <.01

09/04/03 1100 R <.01

Supplemental Information 35
Table 14. Concentrations of selected pesticides and pesticide degradation products analyzed by the U.S. Geological Survey National 

Water-Quality Laboratory (Lakewood, Colorado) schedule 2001 for water samples collected from 22 surface-water sampling sites in five 

Southern States, 2003–04.

[Water samples analyzed for the following pesticides were not detected: 2,6-diethylaniline, acetochlor, alpha-HCH, azinphos-methyl, benfluralin, butylate, 

cis-permethrin, dacthal, desulfinylfipronil, desulfinylfipronil amide, dieldrin, disulfoton, EPTC, ethalfluralin, ethoprop, fipronil, fipronil sulfide, fipronil sulfone, 

fonofos, lindane, linuron, molinate, napropamide, p,p’-DDE, parathion-methyl, pebulate, phorate, propachlor, propyzamide, terbufos, thiobencarb, and triallate. 

<, less than; E, estimated; --, no data]

Map

number

(fig. 1)

Site name

Site

identification

number

Date

(month/

day/year)

Collection

time

(24-hour)

Concentrations, in micrograms per liter

AlachlorAtrazineCarbaryl

CarbofuranChlorpyrifosCyanazine

Alabama

1 Big Creek at State Highway 203 

near Rehobeth

02358765 06/25/03 1220 <0.005 <0.007 <0.041 <0.02 <0.005 <0.018

08/06/03 1140 <.005 <.007 <.041 <.02 <.005 <.018

09/17/03 1220 <.005 <.007 <.041 <.02 <.005 <.018

2 Cedar Creek at East Cook Road 

near Pansey

02343848 06/26/03 1210 <.005 <.007 <.041 <.02 <.005 <.018

08/04/03 1105 .0069 <.007 <.041 <.02 <.005 <.018

09/15/03 1545 <.005 <.007 <.041 <.02 <.005 <.018

06/15/04 1250 <.005 E.005 <.041 <.02 <.005 <.018

09/17/04 1220 <.005 .012 <.041 <.02 <.005 <.018

3 Cowarts Creek above 

Cottonwood

0235878075 06/26/03 1515 <.005 .013 <.041 <.02 <.005 <.018

08/05/03 0900 <.005 <.007 <.041 <.02 <.005 <.018

09/16/03 1225 <.005 <.007 <.041 <.02 <.005 <.018

4 Cowarts Creek near Love Hill 0235878055 06/25/03 1730 <.005 .014 <.041 <.02 <.005 <.018

08/05/03 1300 <.005 <.007 <.041 <.02 <.005 <.018

09/16/03 1550 <.005 <.007 <.041 <.02 <.005 <.018

5 Spring Creek at County Road 55 

near Geneva

02365100 06/25/03 0810 <.005 .013 <.041 <.02 <.005 <.018

08/06/03 0810 <.005 <.007 <.041 <.02 <.005 <.018

09/17/03 0900 E.004 E.006 <.041 <.02 <.005 <.018

Florida

6 Moore Creek near Chumuckla 02375800 06/23/03 1125 .010 <.007 <.041 <.02 <.005 <.018

07/29/03 1215 .015 <.007 <.041 E.006 <.005 <.018

09/25/03 1200 .008 <.007 <.041 <.02 <.005 <.018

7 Pond Creek near Milton 02370700 06/23/03 1500 <.005 <.007 <.041 <.02 <.005 <.018

07/29/03 1435 <.005 <.007 <.041 <.02 <.005 <.018

09/24/03 1400 <.005 <.007 <.041 <.02 <.005 <.018

06/14/04 1310 <.005 <.007 <.041 <.02 <.005 <.018

09/23/04 0830 <.005 <.007 <.041 <.02 <.005 <.018

8 Russ Mill Creek at Union Road 

near Cottondale

02358778 06/24/03 1330 <.005 E.006 <.041 <02 <.005 <.018

36  Results of Analyses of the Fungicide Chlorothalonil, Its Degradation Products, and Other Selected Pesticides
Table 14. Concentrations of selected pesticides and pesticide degradation products analyzed by the U.S. Geological Survey National 

Water-Quality Laboratory (Lakewood, Colorado) schedule 2001 for water samples collected from 22 surface-water sampling sites in five 

Southern States, 2003–04.—Continued

[Water samples analyzed for the following pesticides were not detected: 2,6-diethylaniline, acetochlor, alpha-HCH, azinphos-methyl, benfluralin, butylate, 

cis-permethrin, dacthal, desulfinylfipronil, desulfinylfipronil amide, dieldrin, disulfoton, EPTC, ethalfluralin, ethoprop, fipronil, fipronil sulfide, fipronil sulfone, 

fonofos, lindane, linuron, molinate, napropamide, p,p’-DDE, parathion-methyl, pebulate, phorate, propachlor, propyzamide, terbufos, thiobencarb, and triallate. 

<, less than; E, estimated; --, no data]

Map

number

(fig. 1)

Site name

Site

identification

number

Date

(month/

day/year)

Collection

time

(24-hour)

Concentrations, in micrograms per liter

AlachlorAtrazineCarbaryl

CarbofuranChlorpyrifosCyanazine

Florida—Continued

8 Russ Mill Creek at Union Road 

near Cottondale

02358778 08/05/03 1640 <0.005 <0.007 <0.041 <0.02 <0.005 <0.018

09/16/03 0825 <.005 <.007 <.041 <.02 <.005 <.018

9 West Fork Big Coldwater Creek 

near Allentown

02370400 06/24/03 0900 <.005 <.007 <.041 <.02 <.005 <.018

07/30/03 0800 .011 <.007 <.041 <.02 <.005 <.018

09/25/03 0845 .006 <.007 <.041 <.02 <.005 <.018

Georgia

10 Big Creek at Crystal Lake Road 

near Irwinville

02315919 07/16/03 1340 <.005 .010 <.041 <.02 <.005 <.018

08/13/03 0710 <.005 .010 E.007 <.02 <.005 <.018

09/24/03 0715 <.005 <.007 <.041 <.02 <.005 <.018

11 Black Creek near Blitchton 02202600 07/14/03 1020 <.005 <.007 <.041 <.02 <.005 <.018

08/11/03 0945 <.005 <.007 <.041 <.02 <.005 <.018

09/22/03 1230 <.005 <.007 <.041 <.02 <.005 <.018

06/23/04 0630 <.005 <.007 <.041 <.02 <.005 <.018

06/24/04 0915 <.005 <.007 <.041 <.02 <.005 <.018

09/07/04 0340 <.005 <.007 <.041 <.02 <.005 <.018

12 Bridge Creek at James King 

Road near Doerun

2327314 07/15/03 1115 <.005 .016 <.041 <.02 <.005 <.018

08/12/03 1000 <.005 .012 <.041 <.02 <.005 <.018

09/23/03 0800 <.005 <.007 <.041 <.02 <.005 <.018

07/08/04 1900 <.005 E.006 <.041 <.02 .018 <.018

09/06/04 1345 <.005 <.007 <.041 <.02 .008 <.018

13 Coheelee Creek at River Road 

near Hilton

2343410 06/26/03 0815 <.005 <.007 <.041 <.02 <.005 <.018

08/04/03 1435 <.005 .505 <.041 <.02 <.005 <.018

09/15/03 1220 <.005 .018 <.041 <.02 <.005 <.018

06/15/04 1510 <.005 .013 <.041 <.02 .018 E.008

09/17/04 1530 <.005 .012 <.041 <.02 .008 <.018

14 Little Abrams Creek at GA 

Highway 313 near Doles

2350522 07/15/03 1500 <.005 <.007 <.041 <.02 <.005 <.018

08/12/03 1300 .041 .012 <.041 <.02 <.005 <.018

09/23/03 1350 <.005 .284 <.041 <.02 <.005 <.018

07/08/04 1035 <.005 .064 <.041 <.02 E.004 <.018

Supplemental Information 37
Table 14. Concentrations of selected pesticides and pesticide degradation products analyzed by the U.S. Geological Survey National 

Water-Quality Laboratory (Lakewood, Colorado) schedule 2001 for water samples collected from 22 surface-water sampling sites in five 

Southern States, 2003–04.—Continued

[Water samples analyzed for the following pesticides were not detected: 2,6-diethylaniline, acetochlor, alpha-HCH, azinphos-methyl, benfluralin, butylate, 

cis-permethrin, dacthal, desulfinylfipronil, desulfinylfipronil amide, dieldrin, disulfoton, EPTC, ethalfluralin, ethoprop, fipronil, fipronil sulfide, fipronil sulfone, 

fonofos, lindane, linuron, molinate, napropamide, p,p’-DDE, parathion-methyl, pebulate, phorate, propachlor, propyzamide, terbufos, thiobencarb, and triallate. 

<, less than; E, estimated; --, no data]

Map

number

(fig. 1)

Site name

Site

identification

number

Date

(month/

day/year)

Collection

time

(24-hour)

Concentrations, in micrograms per liter

AlachlorAtrazineCarbaryl

CarbofuranChlorpyrifosCyanazine

Georgia—Continued

15 Reedy Creek at U.S. Highway 

129 near Ocilla

2316217 07/16/03 0745 <0.005 0.014 <0.041 <0.02 <0.005 <0.018

08/13/03 1345 <.005 .023 E.006 <.02 <.005 <.018

09/24/03 1340 <.005 E.005 <.041 <.02 <.005 <.018

16 Warrior Creek near Sumner 2317870 07/15/03 0750 <.005 .011 <.041 <.02 <.005 <.018

08/12/03 0715 <.005 .044 <.041 <.02 <.005 E.011

09/23/03 1020 <.005 .018 <.041 <.02 <.005 <.018

07/08/04 1420 <.005 .014 <.041 <.02 <.005 <.018

09/06/04 1530 <.005 <.007 <.041 <.02 <.005 <.018

17 Willacoochee Creek at Frank 

Road near Ocilla

02316134 07/16/03 1100 <.005 .014 <.041 <.02 <.005 <.018

08/13/03 0930 <.005 .016 <.041 <.02 <.005 <.018

09/24/03 1000 <.005 .008 <.041 <.02 <.005 <.018

Oklahoma

18 Cobb Creek near Eakly 07325800 07/15/03 1030 <.005 E.006 <.041 <.02 <.005 <.018

07/30/03 1200 <.005 .010 <.041 <.02 <.005 <.018

12/03/03 1015 <.005 .009 <.041 <.02 <.005 <.018

08/15/04 1630 <.005 .014 <.041 <.02 <.005 <.018

08/28/04 1700 <.005 <.007 <.041 <.02 <.005 <.018

10/07/04 2130 <.005 .018 <.041 <.02 <.005 <.018

19 Cobb Creek near Fort Cobb 07326000 07/15/03 1430 <.005 .043 <.041 <.02 <.005 <.018

12/03/03 1400 <.005 <.007 <.041 <.02 <.005 <.018

08/15/04 1930 <.005 .038 <.041 <.02 <.005 <.018

08/30/04 1300 <.005 .034 <.041 <.02 <.005 <.018

10/12/04 1230 <.005 .028 <.041 <.02 <.005 <.018

Texas

20 Beaver Creek near Electra 07312200 07/18/03 1415 <.005 .024 <.041 <.02 <.005 <.018

08/30/03 1305 <.005 .024 <.041 <.02 <.005 <.018

21 Sabana River near DeLeon 08099300 07/09/03 1240 <.005 <.007 <.041 <.02 <.005 <.018

09/03/03 1030 <.005 <.007 <.041 <.02 <.005 <.018

12/11/03 1130 <.005 <.007 <.041 <.02 <.005 <.018

38  Results of Analyses of the Fungicide Chlorothalonil, Its Degradation Products, and Other Selected Pesticides
Table 14. Concentrations of selected pesticides and pesticide degradation products analyzed by the U.S. Geological Survey National 

Water-Quality Laboratory (Lakewood, Colorado) schedule 2001 for water samples collected from 22 surface-water sampling sites in five 

Southern States, 2003–04.—Continued

[Water samples analyzed for the following pesticides were not detected: 2,6-diethylaniline, acetochlor, alpha-HCH, azinphos-methyl, benfluralin, butylate, 

cis-permethrin, dacthal, desulfinylfipronil, desulfinylfipronil amide, dieldrin, disulfoton, EPTC, ethalfluralin, ethoprop, fipronil, fipronil sulfide, fipronil sulfone, 

fonofos, lindane, linuron, molinate, napropamide, p,p’-DDE, parathion-methyl, pebulate, phorate, propachlor, propyzamide, terbufos, thiobencarb, and triallate. 

<, less than; E, estimated; --, no data]

Map

number

(fig. 1)

Site name

Site

identification

number

Date

(month/

day/year)

Collection

time

(24-hour)

Concentrations, in micrograms per liter

AlachlorAtrazineCarbaryl

CarbofuranChlorpyrifosCyanazine

22 San Miguel Creek near Tilden 08206700 07/15/03 1050 <0.005 0.122 <0.041 <0.02 <0.005 <0.018

07/17/03 0910 <.005 .008 E.027 <.02 <.005 <.018

09/04/03 1100 <.005 <.007 <.041 <.02 <.005 <.018

Supplemental Information 39
Table 14. Concentrations of selected pesticides and pesticide degradation products analyzed by the U.S. Geological Survey National 

Water-Quality Laboratory (Lakewood, Colorado) schedule 2001 for water samples collected from 22 surface-water sampling sites in 

five Southern States, 2003–04.—Continued

[Water samples analyzed for the following pesticides were not detected: 2,6-diethylaniline, acetochlor, alpha-HCH, azinphos-methyl, benfluralin, butylate, cispermethrin, dacthal, desulfinylfipronil, desulfinylfipronil amide, dieldrin, disulfoton, EPTC, ethalfluralin, ethoprop, fipronil, fipronil sulfide, fipronil sulfone, 

fonofos, lindane, linuron, molinate, napropamide, p,p’-DDE, parathion-methyl, pebulate, phorate, propachlor, propyzamide, terbufos, thiobencarb, and triallate. <, less than; E, estimated; --, no data]

Map 

number 

(fig. 1)

Site name

Concentrations, in micrograms per liter

Deethylatrazine

Diazinon

Ethalfluralin

MalathionMetolachlorMetribuzinParathion

Pendimethalin

PrometonPropanil

Alabama

1 Big Creek at State Highway 203 near Rehobeth<0.006 <0.005 <0.009 <0.027 <0.006 <0.006 <0.010 <0.022 <0.010 <0.011

<.006 <.005 <.009 <.027 <.006 <.006 <.010 <.022 <.010 <.011

<.006 <.005 <.009 <.027 <.006 <.006 <.010 <.022 <.010 <.011

2 Cedar Creek at East Cook 

Road near Pansey

<.006 <.005 <.009 <.027 E.009 <.006 <.010 <.022 <.010 <.011

<.006 <.005 <.009 <.027 E.012 <.006 <.010 <.022 <.010 <.011

<.006 <.005 <.009 <.027 E.008 <.006 <.010 <.022 <.010 <.011

E.004 <.005 E.003 <.027 E.007 <.006 <.010 <.022 <.010 <.011

<.006 <.005 <.009 <.027 <.006 <.006 <.010 <.022 .015 <.011

3 Cowarts Creek above 

Cottonwood

<.006 <.005 <.009 <.027 <.006 <.006 <.010 <.022 <.010 <.011

<.006 <.005 <.009 <.027 <.006 <.006 <.010 <.022 <.010 <.011

<.006 <.005 <.009 <.027 <.006 <.006 <.010 <.022 <.010 <.011

4 Cowarts Creek near Love 

Hill

<.006 <.005 <.009 <.027 <.006 <.006 <.010 <.022 <.010 <.011

<.006 <.005 <.009 <.027 <.006 <.006 <.010 <.022 <.010 <.011

<.006 <.005 <.009 <.027 <.006 <.006 <.010 <.022 E.004 <.011

5 Spring Creek at County 

Road 55 near Geneva

E.005 <.005 <.009 <.027 .014 <.006 <.010 <.022 <.010 <.011

<.006 <.005 <.009 <.027 <.006 <.006 <.010 <.022 <.010 <.011

<.006 <.005 <.009 <.027 E.01 <.006 <.010 <.022 <.010 <.011

Florida

6 Moore Creek near 

Chumuckla

<.006 <.005 <.009 <.027 .016 <.006 <.010 <.022 <.010 <.011

<.006 <.005 <.009 <.027 .025 <.006 <.010 <.022 <.010 <.011

<.006 <.005 <.009 <.027 .021 <.006 <.010 <.022 <.010 <.011

7 Pond Creek near Milton <.006 <.005 <.009 <.027 E.005 <.006 <.010 <.022 <.010 <.011

<.006 <.005 <.009 <.027 E.004 <.006 <.010 <.022 <.010 <.011

<.006 <.005 <.009 <.027 E.007 <.006 <.010 <.022 <.010 <.011

<.006 <.005 <.009 <.027 E.011 <.006 <.010 <.022 <.010 <.011

<.006 <.005 <.009 <.027 <.006 <.006 <.010 <.022 <.010 <.011

40 Results of Analyses of the Fungicide Chlorothalonil, Its Degradation Products, and Other Selected Pesticides
Table 14. Concentrations of selected pesticides and pesticide degradation products analyzed by the U.S. Geological Survey National 

Water-Quality Laboratory (Lakewood, Colorado) schedule 2001 for water samples collected from 22 surface-water sampling sites in 

five Southern States, 2003–04.—Continued

[Water samples analyzed for the following pesticides were not detected: 2,6-diethylaniline, acetochlor, alpha-HCH, azinphos-methyl, benfluralin, butylate, cispermethrin, dacthal, desulfinylfipronil, desulfinylfipronil amide, dieldrin, disulfoton, EPTC, ethalfluralin, ethoprop, fipronil, fipronil sulfide, fipronil sulfone, 

fonofos, lindane, linuron, molinate, napropamide, p,p’-DDE, parathion-methyl, pebulate, phorate, propachlor, propyzamide, terbufos, thiobencarb, and triallate. <, less than; E, estimated; --, no data]

Map 

number 

(fig. 1)

Site name

Concentrations, in micrograms per liter

Deethylatrazine

Diazinon

Ethalfluralin

MalathionMetolachlorMetribuzinParathion

Pendimethalin

PrometonPropanil

Florida—Continued

8 Russ Mill Creek at Union 

Road near Cottondale

E0.006 <0.005 <0.009 <0.027 <0.006 <0.006 <0.010 <0.022 <0.010 <0.011

<.006 <.005 <.009 <.027 <.006 <.006 <.010 <.022 <.010 <.011

<.006 <.005 <.009 <.027 <.006 <.006 <.010 <.022 <.010 <.011

9 West Fork Big Coldwater 

Creek near Allentown

<.006 <.005 <.009 <.027 .049 <.006 <.010 <.022 <.010 <.011

<.006 <.005 <.009 <.027 .015 <.006 <.010 <.022 <.010 <.011

<.006 <.005 <.009 <.027 .015 <.006 <.010 <.022 <.010 <.011

Georgia

10 Big Creek at Crystal Lake 

Road near Irwinville 

<.006 <.005 <.009 <.027 .058 <.006 <.010 <.022 <.010 <.011

<.006 <.005 <.009 <.027 .014 .009 <.010 <.022 <.010 <.011

<.006 <.005 <.009 <.027 E.010 <.006 <.010 <.022 <.010 <.011

11 Black Creek near Blitchton <.006 <.005 <.009 <.027 <.006 <.006 <.010 <.022 <.010 <.011

<.006 <.005 <.009 <.027 E.006 <.006 <.010 <.022 <.010 <.011

<.006 <.005 <.009 E.007 <.006 <.006 <.010 <.022 <.010 <.011

<.006 <.005 <.009 <.027 <.006 <.006 <.010 <.022 <.010 <.011

<.006 <.005 <.009 <.027 <.006 <.006 <.010 <.022 <.010 <.011

<.006 <.005 <.009 <.027 <.006 <.006 <.010 <.022 <.010 <.011

12 Bridge Creek at James 

King Road near Doerun

E.004 <.005 <.009 <.027 <.006 <.006 <.010 <.022 <.010 <.011

E.004 <.005 <.009 <.027 E.006 E.004 <.010 <.022 E.003 <.011

<.006 <.005 <.009 <.027 <.006 <.006 <.010 <.022 <.010 <.011

E.003 <.005 <.009 <.027 E.007 <.006 <.010 <.022 .005 <.011

<.006 <.005 <.009 <.027 E.005 <.006 <.010 <.022 <.010 <.011

13 Coheelee Creek at River 

Road near Hilton

<.006 <.005 <.009 <.027 E.009 <.006 <.010 <.022 <.010 <.011

E.022 <.005 <.009 <.027 .063 <.006 <.010 <.022 <.010 <.011

<.006 <.005 <.009 <.027 E.009 <.006 <.010 <.022 <.010 <.011

E.003 <.005 .022 <.027 .0173 <.006 <.010 E.010 .005 <.011

<.006 <.005 <.009 <.027 .0190 <.006 <.010 <.022 <.010 <.011

14 Little Abrams Creek at GA 

Highway 313 near Doles

<.006 <.005 <.009 <.027 <.006 <.006 <.010 <.022 <.010 <.011

<.006 <.005 <.009 <.027 <.006 .046 <.010 <.022 <.010 <.011

Supplemental Information 41
Table 14. Concentrations of selected pesticides and pesticide degradation products analyzed by the U.S. Geological Survey National 

Water-Quality Laboratory (Lakewood, Colorado) schedule 2001 for water samples collected from 22 surface-water sampling sites in 

five Southern States, 2003–04.—Continued

[Water samples analyzed for the following pesticides were not detected: 2,6-diethylaniline, acetochlor, alpha-HCH, azinphos-methyl, benfluralin, butylate, cispermethrin, dacthal, desulfinylfipronil, desulfinylfipronil amide, dieldrin, disulfoton, EPTC, ethalfluralin, ethoprop, fipronil, fipronil sulfide, fipronil sulfone, 

fonofos, lindane, linuron, molinate, napropamide, p,p’-DDE, parathion-methyl, pebulate, phorate, propachlor, propyzamide, terbufos, thiobencarb, and triallate. <, less than; E, estimated; --, no data]

Map 

number 

(fig. 1)

Site name

Concentrations, in micrograms per liter

Deethylatrazine

Diazinon

Ethalfluralin

MalathionMetolachlorMetribuzinParathion

Pendimethalin

PrometonPropanil

Georgia—Continued

14 Little Abrams Creek at GA 

Highway 313 near Doles

E0.050 <0.005 <0.009 <0.027 E0.005 E0.005 <0.010 <0.022 <0.010 <0.011

E.004 <.005 .009 <.027 E.007 <.006 <.010 E.013 E.005 <.011

15 Reedy Creek at U.S. Highway 129 near Ocilla<.006 <.005 <.009 <.027 .023 <.006 <.010 <.022 <.010 <.011

E.005 <.005 <.009 <.027 .016 <.006 <.010 <.022 <.010 <.011

<.006 <.005 <.009 <.027 E.008 <.006 E.007 <.022 <.010 <.011

16 Warrior Creek near Sumner <.006 <.005 <.009 <.027 E.010 <.006 <.010 <.022 .030 <.011

E.005 <.005 <.009 <.027 .013 E.004 <.010 <.022 E.005 <.011

<.006 <.005 <.009 <.027 E.006 <.006 <.010 <.022 <.010 <.011

<.006 .011 <.009 E.022 .028 <.006 <.010 <.022 .017 E.003

<.006 <.005 <.009 <.027 <.006 <.006 <.010 <.022 <.010 <.011

17 Willacoochee Creek at 

Frank Road near Ocilla

<.006 <.005 <.009 <.027 .018 <.006 <.010 <.022 .031 <.011

<.006 <.005 <.009 <.027 E.010 E.004 <.010 <.022 E.012 <.011

<.006 <.005 <.009 <.027 E.008 <.006 <.010 <.022 E.013 <.011

Oklahoma

18 Cobb Creek near Eakly E.007 <.005 <.009 <.027 E.004 <.006 <.010 <.022 <.010 <.011

E.009 <.005 <.009 <.027 E.001 <.006 <.010 .040 <.010 <.011

<.006 <.005 <.009 <.027 E.008 <.006 <.010 <.022 <.010 <.011

<.006 <.005 <.009 <.027 <.006 <.006 <.010 <.022 <.010 <.011

<.006 <.005 <.009 <.027 <.006 <.006 <.010 <.022 <.010 <.011

E.006 <.005 <.009 <.027 E.006 <.006 <.010 <.022 <.010 <.011

19 Cobb Creek near Fort Cobb E.012 <.005 <.009 <.027 <.006 <.006 <.010 <.022 <.010 <.011

E.012 <.005 <.009 <.027 <.006 <.006 <.010 <.022 <.010 <.011

E.012 <.005 <.009 <.027 E.004 <.006 <.010 <.022 E.004 <.011

E.012 <.005 <.009 <.027 <.006 <.006 <.010 <.022 <.010 <.011

E.012 <.005 <.009 <.027 <.006 <.006 <.010 <.022 <.010 <.011

Texas

20 Beaver Creek near Electra E.006 <.005 <.009 <.027 <.006 <.006 <.010 <.022 <.010 <.011

E.006 <.005 <.009 .033 <.006 <.006 <.010 <.022 <.010 <.011

42 Results of Analyses of the Fungicide Chlorothalonil, Its Degradation Products, and Other Selected Pesticides
Table 14. Concentrations of selected pesticides and pesticide degradation products analyzed by the U.S. Geological Survey National 

Water-Quality Laboratory (Lakewood, Colorado) schedule 2001 for water samples collected from 22 surface-water sampling sites in 

five Southern States, 2003–04.—Continued

[Water samples analyzed for the following pesticides were not detected: 2,6-diethylaniline, acetochlor, alpha-HCH, azinphos-methyl, benfluralin, butylate, cispermethrin, dacthal, desulfinylfipronil, desulfinylfipronil amide, dieldrin, disulfoton, EPTC, ethalfluralin, ethoprop, fipronil, fipronil sulfide, fipronil sulfone, 

fonofos, lindane, linuron, molinate, napropamide, p,p’-DDE, parathion-methyl, pebulate, phorate, propachlor, propyzamide, terbufos, thiobencarb, and triallate. <, less than; E, estimated; --, no data]

Map 

number 

(fig. 1)

Site name

Concentrations, in micrograms per liter

Deethylatrazine

Diazinon

Ethalfluralin

MalathionMetolachlorMetribuzinParathion

Pendimethalin

PrometonPropanil

Texas—Continued

21 Sabana River near DeLeon <0.006 <0.005 <0.009 <0.027 E0.010 <0.006 <0.010 <0.022 <0.010 <0.011

<.006 <.005 <.009 <.027 .019 <.006 <.010 <.022 <.010 <.011

<.006 <.005 <.009 <.027 <.006 <.006 <.010 <.022 <.010 <.011

22 San Miguel Creek near 

Tilden

E.040 <.005 <.009 <.027 E.007 <.006 <.010 <.022 <.010 <.011

<.006 <.005 <.009 <.027 <.006 <.006 <.010 <.022 <.010 <.011

<.006 <.005 <.009 <.027 .019 <.006 <.010 <.022 <.010 <.011

Supplemental Information 43
Table 14. Concentrations of selected pesticides and pesticide degradation products analyzed by the U.S. Geological Survey National 

Water-Quality Laboratory (Lakewood, Colorado) schedule 2001 for water samples collected from 22 surface-water sampling sites in 

five Southern States, 2003–04.—Continued

[Water samples analyzed for the following pesticides were not detected: 2,6-diethylaniline, acetochlor, alpha-HCH, azinphos-methyl, benfluralin, butylate, 

cis-permethrin, dacthal, desulfinylfipronil, desulfinylfipronil amide, dieldrin, disulfoton, EPTC, ethalfluralin, ethoprop, fipronil, fipronil sulfide, fipronil sulfone, fonofos, lindane, linuron, molinate, napropamide, p,p’-DDE, parathion-methyl, pebulate, phorate, propachlor, propyzamide, terbufos, thiobencarb, and 

triallate. <, less than; E, estimated; --, no data]

Map 

number 

(fig. 1)

Site name

Concentrations, in micrograms per liter

Propargite Simazine Terbuthiuron Terbacil Trifluralin

Alabama

1 Big Creek at State Highway 203 near Rehobeth <0.023 <0.005 <0.016 <0.034 <0.009

<.023 <.005 <.016 <.034 <.009

<.023 <.005 <.016 <.034 <.009

2 Cedar Creek at East Cook Road near Pansey <.023 <.005 <.016 <.034 <.009

<.023 .006 E.015 <.034 <.009

<.023 .007 E.011 <.034 <.009

<.023 .018 E.011 <.034 <.009

<.023 <.005 <.016 <.034 <.009

3 Cowarts Creek above Cottonwood <.023 <.005 <.016 <.034 E.013

E.012 <.005 <.016 <.034 <.009

<.023 E.005 <.016 <.034 <.009

4 Cowarts Creek near Love Hill <.023 <.005 <.016 <.034 <.009

<.023 .027 <.016 <.034 <.009

<.023 <.005 <.016 <.034 <.009

5 Spring Creek at County Road 55 near Geneva <.023 <.005 <.016 <.034 <.009

<.023 <.005 <.016 <.034 <.009

<.023 <.005 <.016 <.034 <.009

Florida

6 Moore Creek near Chumuckla <.023 <.005 <.016 <.034 <.009

<.023 <.005 <.016 <.034 <.009

<.023 <.005 <.016 <.034 <.009

7 Pond Creek near Milton <.023 <.005 <.016 <.034 <.009

<.023 <.005 <.016 <.034 <.009

<.023 <.005 E.007 <.034 <.009

<.023 <.005 E.011 <.034 <.009

.032 <.005 <.016 <.034 <.009

8 Russ Mill Creek at Union Road near 

Cottondale

<.023 <.005 <.016 <.034 <.009

<.023 <.005 <.016 <.034 <.009

44 Results of Analyses of the Fungicide Chlorothalonil, Its Degradation Products, and Other Selected Pesticides
Table 14. Concentrations of selected pesticides and pesticide degradation products analyzed by the U.S. Geological Survey National 

Water-Quality Laboratory (Lakewood, Colorado) schedule 2001 for water samples collected from 22 surface-water sampling sites in 

five Southern States, 2003–04.—Continued

[Water samples analyzed for the following pesticides were not detected: 2,6-diethylaniline, acetochlor, alpha-HCH, azinphos-methyl, benfluralin, butylate, 

cis-permethrin, dacthal, desulfinylfipronil, desulfinylfipronil amide, dieldrin, disulfoton, EPTC, ethalfluralin, ethoprop, fipronil, fipronil sulfide, fipronil sulfone, fonofos, lindane, linuron, molinate, napropamide, p,p’-DDE, parathion-methyl, pebulate, phorate, propachlor, propyzamide, terbufos, thiobencarb, and 

triallate. <, less than; E, estimated; --, no data]

Map 

number 

(fig. 1)

Site name

Concentrations, in micrograms per liter

Propargite Simazine Terbuthiuron Terbacil Trifluralin

Florida—Continued

8 Russ Mill Creek at Union Road near 

Cottondale

<0.023 <0.005 <0.016 <0.034 <0.009

9 West Fork Big Coldwater Creek near 

Allentown

<.023 <.005 <.016 <.034 <.009

<.023 <.005 <.016 <.034 <.009

<.023 <.005 <.016 <.034 <.009

Georgia

10 Big Creek at Crystal Lake Road near Irwinville <.023 <.005 <.016 <.034 <.009

<.023 <.005 <.016 <.034 <.009

<.023 <.005 <.016 <.034 <.009

11 Black Creek near Blitchton <.023 <.005 <.016 <.034 <.009

<.023 <.005 <.016 <.034 <.009

<.023 <.005 <.016 <.034 <.009

<.023 <.005 <.016 <.034 <.009

<.023 <.005 <.016 <.034 <.009

<.023 <.005 <.016 <.034 <.009

12 Bridge Creek at James King Road near Doerun <.023 <.005 <.016 <.034 <.009

<.023 .006 <.016 <.034 <.009

<.023 <.005 <.016 <.034 <.009

<.023 <.005 <.016 <.034 <.009

<.023 <.005 <.016 <.034 <.009

13 Coheelee Creek at River Road near Hilton <.023 <.005 <.016 <.034 <.009

<.023 <.005 <.016 <.034 <.009

<.023 <.005 <.016 <.034 <.009

<.023 <.005 <.016 <.034 E.008

<.023 <.005 <.016 <.034 <.009

14 Little Abrams Creek at GA Highway 313 near 

Doles

<.023 <.005 <.016 <.034 <.009

<.023 <.005 E.007 <.034 <.009

<.023 .010 <.016 <.034 <.009

<.023 <.005 <.016 <.034 E.008

15 Reedy Creek at U.S. Highway 129 near Ocilla <.023 <.005 <.016 <.034 <.009

Supplemental Information 45
Table 14. Concentrations of selected pesticides and pesticide degradation products analyzed by the U.S. Geological Survey National 

Water-Quality Laboratory (Lakewood, Colorado) schedule 2001 for water samples collected from 22 surface-water sampling sites in 

five Southern States, 2003–04.—Continued

[Water samples analyzed for the following pesticides were not detected: 2,6-diethylaniline, acetochlor, alpha-HCH, azinphos-methyl, benfluralin, butylate, 

cis-permethrin, dacthal, desulfinylfipronil, desulfinylfipronil amide, dieldrin, disulfoton, EPTC, ethalfluralin, ethoprop, fipronil, fipronil sulfide, fipronil sulfone, fonofos, lindane, linuron, molinate, napropamide, p,p’-DDE, parathion-methyl, pebulate, phorate, propachlor, propyzamide, terbufos, thiobencarb, and 

triallate. <, less than; E, estimated; --, no data]

Map 

number 

(fig. 1)

Site name

Concentrations, in micrograms per liter

Propargite Simazine Terbuthiuron Terbacil Trifluralin

Georgia—Continued

15 Reedy Creek at U.S. Highway 129 near Ocilla <0.023 <0.005 <0.016 <0.034 <0.009

<.023 <.005 <.016 <.034 <.009

16 Warrior Creek near Sumner <.023 <.005 <.016 <.034 <.009

<.023 <.005 <.016 <.034 <.009

<.023 <.005 <.016 <.034 <.009

<.023 <.005 <.016 <.034 <.009

<.023 <.005 <.016 <.034 <.009

17 Willacoochee Creek at Frank Road near Ocilla <.023 <.005 .018 <.034 <.009

<.023 <.005 E.010 <.034 <.009

<.023 .117 .022 <.034 <.009

Oklahoma

18 Cobb Creek near Eakly <.023 <.005 <.016 <.034 <.009

<.023 <.005 <.016 E.008 <.009

<.023 <.005 <.016 <.034 <.009

<.023 <.005 <.016 <.034 <.009

<.023 <.005 <.016 <.034 <.009

<.023 <.005 E.004 <.034 <.009

19 Cobb Creek near Fort Cobb .007 E.007 <.016 <.034 <.009

<.023 <.005 <.016 <.034 <.009

.008 E.008 <.016 <.034 <.009

.007 <.005 <.016 <.034 <.009

<.023 <.005 <.016 <.034 <.009

Texas

20 Beaver Creek near Electra <.023 <.005 <.016 <.034 <.009

<.023 <.005 <.016 <.034 <.009

21 Sabana River near DeLeon <.023 <.005 <.016 <.034 <.009

<.023 <.005 <.016 <.034 <.009

<.023 <.005 <.016 <.034 <.009

22 San Miguel Creek near Tilden <.023 <.005 <.016 <.034 <.009

<.023 <.005 E.008 <.034 <.009

<.023 <.005 <.016 <.034 <.009

46  Results of Analyses of the Fungicide Chlorothalonil, Its Degradation Products, and Other Selected Pesticides
Table 15. Concentrations of selected pesticides and pesticide degradation products analyzed by the U.S. Geological Survey National 

Water-Quality Laboratory (Lakewood, Colorado) schedule 2060 for water samples collected from 22 surface-water sampling sites in 

five Southern States, 2003–04.

[Water samples analyzed for the following pesticides were not detected: 2,4-D methyl ester, 2,4-DB, 3(4-chlorophenyl)-1-methyl urea, 3-hydroxycarbofuran, 

3-ketocarbofuran, aldicarb, aldicarb sulfone, aldicarb sulfoxide, bendiocarb, benomyl, bromacil, bromoxynil, carbaryl, carbofuran, chloramben methyl ester, 

chlordiamine-s-triazine, chlorimuron-ethyl, clopyralid, cycloate, dacthal monoacid, deethylatrazine, dicamba, dichlorprop, diphenamid, flumetsulam, imazaquin, imazethapyr, imidacloprid, linuron, MCPA, MCPB, metalaxyl, methiocarb, methomyl, metsulfuron-methyl, neburon, nicosulfuron, oxamyl, picloram, 

propham, propoxur, siduron, sulfometuron-methyl, and terbacil. E, estimated; <, less than]

Map 

number 

(fig. 1)

Site name

Site identification 

number

Date (month/

day/year)

Collection 

time 

(24-hour)

Concentrations, micrograms per liter

2,4-D 2-Hydroxyatrazine Acifluorfen

Alabama

2 Cedar Creek at East Cook Road near 

Pansey

02343848 06/15/04 1250 0.026 E0.009 <0.028

09/17/04 1220 <.038 E.019 <.028

Florida

6 Moore Creek near Chumuckla 02375800 09/25/03 1200 <.038 <.032 <.028

7 Pond Creek near Milton 02370700 06/14/04 1310 <.038 <.032 <.028

09/23/04 0830 <.038 <.032 <.028

Georgia

11 Black Creek near Blitchton 02202600 09/22/03 1230 <.038 <.032 <.028

06/24/04 0915 <.038 <.032 <.028

12 Bridge Creek at James King Road near 

Doerun

02327314 07/08/04 1900 .030 E.105 <.028

09/06/04 1345 <.038 E.143 <.028

13 Coheelee Creek at River Road near 

Hilton

02343410 06/15/04 1510 .056 E.052 .029

09/17/04 1530 <.038 E.054 <.028

14 Little Abrams Creek at GA Highway 

313 near Doles

02350522 07/08/04 1035 <.038 <.032 <.028

09/06/04 1830 <.038 <.032 <.028

16 Warrior Creek near Sumner 02317870 07/08/04 1420 <.038 <.032 <.028

09/06/04 1530 <.038 <.032 <.028

Oklahoma

18 Cobb Creek near Eakly 07325800 08/15/04 1630 <.038 <.032 <.028

08/28/04 1700 .037 E.025 <.028

10/07/04 2130 <.038 <.032 <.028

19 Cobb Creek near Fort Cobb 07326000 08/15/04 1930 E.038 E.031 <.028

08/30/04 1300 <.038 E.038 <.028

10/12/04 1230 <.038 E.028 <.028

Supplemental Information 47
Table 15. Concentrations of selected pesticides and pesticide degradation products analyzed by the U.S. Geological Survey National 

Water-Quality Laboratory (Lakewood, Colorado) schedule 2060 for water samples collected from 22 surface-water sampling sites in 

five Southern States, 2003–04.—Continued

[Water samples analyzed for the following pesticides were not detected: 2,4-D methyl ester, 2,4-DB, 3(4-chlorophenyl)-1-methyl urea, 3-hydroxycarbofuran, 

3-ketocarbofuran, aldicarb, aldicarb sulfone, aldicarb sulfoxide, bendiocarb, benomyl, bromacil, bromoxynil, carbaryl, carbofuran, chloramben methyl ester, 

chlordiamine-s-triazine, chlorimuron-ethyl, clopyralid, cycloate, dacthal monoacid, deethylatrazine, dicamba, dichlorprop, diphenamid, flumetsulam, imazaquin, imazethapyr, imidacloprid, linuron, MCPA, MCPB, metalaxyl, methiocarb, methomyl, metsulfuron-methyl, neburon, nicosulfuron, oxamyl, picloram, 

propham, propoxur, siduron, sulfometuron-methyl, and terbacil. E, estimated; <, less than]

Map 

number 

(fig. 1)

Site name

Concentrations, micrograms per liter

Atrazine Bensulfuronmethyl Bentazon Caffeine

Alabama

2 Cedar Creek at East Cook Road near Pansey <0.008 <0.018 <0.012 <0.018

<.008 <.018 E.017 .018

Florida

6 Moore Creek near Chumuckla <.008 <.018 <.012 <.018

7 Pond Creek near Milton <.008 <.018 <.012 .027

<.008 <.018 <.012 E.125

Georgia

11 Black Creek near Blitchton <.008 <.018 <.012 <.018

<.008 <.018 <.012 E.014

12 Bridge Creek at James King Road near Doerun <.008 <.018 E.026 <.018

<.008 <.018 <.012 E.087

13 Coheelee Creek at River Road near Hilton E.005 <.018 E.280 <.018

<.008 <.018 E.043 E.036

14 Little Abrams Creek at GA Highway 313 near Doles .031 <.018 E.0241 <.018

<.008 <.018 <.012 <.018

16 Warrior Creek near Sumner <.008 <.018 <.012 <.018

<.008 E.006 <.012 E.037

Oklahoma

18 Cobb Creek near Eakly E.010 <.018 <.012 <.018

<.008 <.018 E.007 .020

<.008 <.018 <.012 <.018

19 Cobb Creek near Fort Cobb E.024 <.018 <.012 .037

.014 <.018 <.012 .030

.012 <.018 <.012 <.018

48  Results of Analyses of the Fungicide Chlorothalonil, Its Degradation Products, and Other Selected Pesticides
Table 15. Concentrations of selected pesticides and pesticide degradation products analyzed by the U.S. Geological Survey National 

Water-Quality Laboratory (Lakewood, Colorado) schedule 2060 for water samples collected from 22 surface-water sampling sites in 

five Southern States, 2003–04.—Continued

[Water samples analyzed for the following pesticides were not detected: 2,4-D methyl ester, 2,4-DB, 3(4-chlorophenyl)-1-methyl urea, 3-hydroxycarbofuran, 

3-ketocarbofuran, aldicarb, aldicarb sulfone, aldicarb sulfoxide, bendiocarb, benomyl, bromacil, bromoxynil, carbaryl, carbofuran, chloramben methyl ester, 

chlordiamine-s-triazine, chlorimuron-ethyl, clopyralid, cycloate, dacthal monoacid, deethylatrazine, dicamba, dichlorprop, diphenamid, flumetsulam, imazaquin, imazethapyr, imidacloprid, linuron, MCPA, MCPB, metalaxyl, methiocarb, methomyl, metsulfuron-methyl, neburon, nicosulfuron, oxamyl, picloram, 

propham, propoxur, siduron, sulfometuron-methyl, and terbacil. E, estimated; <, less than]

Map 

number 

(fig. 1)

Site name

Concentrations, micrograms per liter

Chlorothalonil Deisopropylatrazine Dinoseb

Alabama

2 Cedar Creek at East Cook Road near Pansey <0.035 <0.08 <0.038

<.035 <.08 <.038

Florida

6 Moore Creek near Chumuckla <.035 <.08 .008

7 Pond Creek near Milton <.035 <.08 <.038

<.035 <.08 <.038

Georgia

11 Black Creek near Blitchton <.035 <.08 <.038

<.035 <.08 <.038

12 Bridge Creek at James King Road near Doerun <.035 <.08 <.038

<.035 <.08 E.087

13 Coheelee Creek at River Road near Hilton <.035 <.08 <.038

<.035 <.08 <.038

14 Little Abrams Creek at GA Hwy 313 near Doles E.161 <.08 <.038

<.035 <.08 <.038

16 Warrior Creek near Sumner <.035 <.08 <.038

E.061 <.08 <.038

Oklahoma

18 Cobb Creek near Eakly <.035 <.08 <.038

<.035 <.08 <.038

<.035 <.08 <.038

19 Cobb Creek near Fort Cobb <.035 <.08 <.038

<.035 <.08 <.038

<.035 E.007 <.038

Supplemental Information 49
Table 15. Concentrations of selected pesticides and pesticide degradation products analyzed by the U.S. Geological Survey National 

Water-Quality Laboratory (Lakewood, Colorado) schedule 2060 for water samples collected from 22 surface-water sampling sites in 

five Southern States, 2003–04.—Continued

[Water samples analyzed for the following pesticides were not detected: 2,4-D methyl ester, 2,4-DB, 3(4-chlorophenyl)-1-methyl urea, 3-hydroxycarbofuran, 

3-ketocarbofuran, aldicarb, aldicarb sulfone, aldicarb sulfoxide, bendiocarb, benomyl, bromacil, bromoxynil, carbaryl, carbofuran, chloramben methyl ester, 

chlordiamine-s-triazine, chlorimuron-ethyl, clopyralid, cycloate, dacthal monoacid, deethylatrazine, dicamba, dichlorprop, diphenamid, flumetsulam, imazaquin, imazethapyr, imidacloprid, linuron, MCPA, MCPB, metalaxyl, methiocarb, methomyl, metsulfuron-methyl, neburon, nicosulfuron, oxamyl, picloram, 

propham, propoxur, siduron, sulfometuron-methyl, and terbacil. E, estimated; <, less than]

Map 

number 

(fig. 1)

Site name

Concentrations, micrograms per liter

Diuron Fenuron Fluometuron Norflurazon Oryzalin

Alabama

2 Cedar Creek at East Cook Road near Pansey 0.685 <0.032 <0.016 <0.020 <0.012

.164 <.032 <.016 <.020 <.012

Florida

6 Moore Creek near Chumuckla <.015 <.032 <.016 .008 <.012

7 Pond Creek near Milton <.015 <.032 <.016 <.020 <.012

<.015 <.032 <.016 <.020 <.012

Georgia

11 Black Creek near Blitchton E.017 <.032 <.016 <.020 <.012

<.015 <.032 <.016 <.020 <.012

12 Bridge Creek at James King Road near Doerun <.015 1.51 <.016 <.020 E.048

<.015 <.032 <.016 <.020 <.012

13 Coheelee Creek at River Road near Hilton .049 E.016 E.016 E.008 <.012

E.023 <.032 E.022 <.020 <.012

14 Little Abrams Creek at GA Highway 313 near Doles <.015 <.032 <.016 <.020 <.012

<.015 <.032 E.009 <.020 <.012

16 Warrior Creek near Sumner E.151 <.032 <.016 <.020 <.012

<.015 <.032 <.016 <.020 <.012

Oklahoma

18 Cobb Creek near Eakly <.015 <.032 <.016 <.020 <.012

<.015 <.032 <.016 <.020 <.012

<.015 <.032 <.016 <.020 <.012

19 Cobb Creek near Fort Cobb <.015 <.032 <.016 <.020 .043

<.015 <.032 <.016 <.020 .126

<.015 <.032 <.016 <.020 .127

50 Results of Analyses of the Fungicide Chlorothalonil, Its Degradation Products, and Other Selected Pesticides
Table 15. Concentrations of selected pesticides and pesticide degradation products analyzed by the U.S. Geological Survey National 

Water-Quality Laboratory (Lakewood, Colorado) schedule 2060 for water samples collected from 22 surface-water sampling sites in 

five Southern States, 2003–04.—Continued

[Water samples analyzed for the following pesticides were not detected: 2,4-D methyl ester, 2,4-DB, 3(4-chlorophenyl)-1-methyl urea, 3-hydroxycarbofuran, 

3-ketocarbofuran, aldicarb, aldicarb sulfone, aldicarb sulfoxide, bendiocarb, benomyl, bromacil, bromoxynil, carbaryl, carbofuran, chloramben methyl ester, 

chlordiamine-s-triazine, chlorimuron-ethyl, clopyralid, cycloate, dacthal monoacid, deethylatrazine, dicamba, dichlorprop, diphenamid, flumetsulam, imazaquin, imazethapyr, imidacloprid, linuron, MCPA, MCPB, metalaxyl, methiocarb, methomyl, metsulfuron-methyl, neburon, nicosulfuron, oxamyl, picloram, 

propham, propoxur, siduron, sulfometuron-methyl, and terbacil. E, estimated; <, less than]

Map 

number 

(fig. 1)

Site name

Concentrations, micrograms per liter

Propiconazole Tebuthiuron Triclopyr

Alabama

2 Cedar Creek at East Cook Road near Pansey <0.010 E0.005 <0.026

<.010 E.005 E.093

Florida

6 Moore Creek near Chumuckla <.010 <.032 <.026

7 Pond Creek near Milton <.010 <.032 <.026

<.010 E.006 <.026

Georgia

11 Black Creek near Blitchton <.010 <.032 <.026

<.010 <.032 <.026

12 Bridge Creek at James King Road near Doerun <.010 <.032 <.026

E.026 E.050 <.026

13 Coheelee Creek at River Road near Hilton <.010 <.032 <.026

<.010 <.032 <.026

14 Little Abrams Creek at GA Highway 313 near Doles E.005 <.032 .355

<.010 <.032 <.026

16 Warrior Creek near Sumner <.010 <.032 <.026

<.010 <.032 <.026

Oklahoma

18 Cobb Creek near Eakly <.010 <.032 E.245

<.010 .023 <.026

<.010 .090 <.026

19 Cobb Creek near Fort Cobb <.010 <.032 <.026

<.010 <.032 <.026

<.010 <.032 <.026

Supplemental Information  51
Table 16. Concentrations of dissolved organic carbon, suspended sediment, and percentage of silt- and clay-sized particles for water 

samples collected from 22 surface-water sampling sites in five Southern States, 2003–04.

[mg/L, milligrams per liter; NR, not measured; <, less than; mm, millimeters]

Map 

number 

(fig. 1)

Site name

Site identification 

number

Date of 

collection 

(month/

day/year)

Collection time 

(24-hour)

Dissolved 

organic 

carbon concentration 

(mg/L)

Suspendedsediment 

concentration (mg/L)

Percentage 

of silt- and 

clay-sized 

particles 

(<0.062 mm)

Alabama

1 Big Creek at State Highway 203 near Rehobeth 02358765 06/25/03 1220 6.2 13 38

08/06/03 1140 6.4 6 80

09/17/03 1220 5.5 56 74

2 Cedar Creek at East Cook Road near Pansey 02343848 06/26/03 1210 1.7 10 80

08/04/03 1105 3.0 5 95

09/15/03 1545 1.6 4 94

06/15/04 1250 3.3 14 87

09/17/04 1220 5.1 26 85

07/13/05 1815 2.6 36 56

3 Cowarts Creek above Cottonwood 0235878075 06/26/03 1515 3.4 13 74

08/05/03 0900 5.3 13 63

09/16/03 1225 3.4 20 67

5 Spring Creek at County Road 55 near Geneva 02365100 06/25/03 0810 7.0 24 73

08/06/03 0810 8.8 19 59

09/17/03 0900 12.0 25 48

Florida

6 Moore Creek near Chumuckla 02375800 06/23/03 1125 2.2 25 56

07/29/03 1215 1.8 5 21

09/25/03 1200 1.2 10 64

7 Pond Creek near Milton 02370700 06/23/03 1500 9.2 40 31

07/29/03 1435 5.4 7 40

09/24/03 1400 3.8 11 45

06/14/04 1310 5.6 9 39

09/23/04 0830 16.0 9 84

07/14/05 1320 16.0 8 83

52 Results of Analyses of the Fungicide Chlorothalonil, Its Degradation Products, and Other Selected Pesticides
Table 16. Concentrations of dissolved organic carbon, suspended sediment, and percentage of silt- and clay-sized particles for water 

samples collected from 22 surface-water sampling sites in five Southern States, 2003–04.—Continued

[mg/L, milligrams per liter; NR, not measured; <, less than; mm, millimeters]

Map 

number 

(fig. 1)

Site name

Site identification 

number

Date of 

collection 

(month/

day/year)

Collection time 

(24-hour)

Dissolved 

organic 

carbon concentration 

(mg/L)

Suspendedsediment 

concentration (mg/L)

Percentage 

of silt- and 

clay-sized 

particles 

(<0.062 mm)

Florida—Continued

8 Russ Mill Creek at Union Road near 

Cottondale

02358778 06/24/03 1330 2.7 15 63

08/05/03 1640 5.6 21 61

09/16/03 0825 2.1 16 89

9 West Fork Big Coldwater Creek near 

Allentown

02370400 06/24/03 0900 6.4 66 64

07/30/03 0800 3.6 4 62

09/25/03 0845 2.8 13 55

Georgia

10 Big Creek at Crystal Lake Road near Irwinville 02315919 07/16/03 1340 15 7 87

08/13/03 0710 19 19 57

09/24/03 0715 18 12 88

11 Black Creek near Blitchton 02202600 07/14/03 1020 41 10 76

08/11/03 0945 39 13 84

09/08/03 0900 NR NR NR

09/08/03 0915 NR NR NR

09/08/03 0930 NR NR NR

09/08/03 0945 NR NR NR

09/08/03 1000 NR NR NR

09/08/03 1015 NR NR NR

09/08/03 1030 NR NR NR

09/08/03 1045 NR NR NR

09/08/03 1100 NR NR NR

09/08/03 1115 NR NR NR

09/08/03 1130 NR NR NR

09/08/03 1145 NR NR NR

09/22/03 1230 34 13 61

10/18/03 1820 NR NR NR

10/18/03 1920 NR NR NR

10/18/03 1950 NR NR NR

10/18/03 2030 NR NR NR

06/23/04 0630 35 NR NR

Supplemental Information  53
Table 16. Concentrations of dissolved organic carbon, suspended sediment, and percentage of silt- and clay-sized particles for water 

samples collected from 22 surface-water sampling sites in five Southern States, 2003–04.—Continued

[mg/L, milligrams per liter; NR, not measured; <, less than; mm, millimeters]

Map 

number 

(fig. 1)

Site name

Site identification 

number

Date of 

collection 

(month/

day/year)

Collection time 

(24-hour)

Dissolved 

organic 

carbon concentration 

(mg/L)

Suspendedsediment 

concentration (mg/L)

Percentage 

of silt- and 

clay-sized 

particles 

(<0.062 mm)

Georgia—Continued

11 Black Creek near Blitchton—Continued 06/24/04 0915 40 10 NR

09/06/04 0940 18 NR NR

09/07/04 0340 25 NR NR

07/11/05 1225 40 NR NR

07/16/05 1555 34 8 83

12 Bridge Creek at James King Road near Doerun 02327314 07/15/03 1115 11 16 72

08/12/03 1000 11 14 50

09/23/03 0800 13 25 87

07/08/04 1900 12 15 NR

09/06/04 1345 12 8 86

07/12/05 1120 9.0 22 87

07/13/05 1610 4.8 10 94

13 Coheelee Creek at River Road near Hilton 02343410 06/26/03 0815 3.2 12 89

08/04/03 1435 6.4 47 65

09/15/03 1220 3.3 3 92

06/15/04 1510 4.9 17 76

09/17/04 1530 8.0 42 73

14 Little Abrams Creek at GA Highway 313 

 near Doles

02350522 07/15/03 1500 16 12 61

08/12/03 1300 20 32 62

09/23/03 1350 12 24 83

07/08/04 1035 16 25 NR

09/06/04 1830 18 39 98

07/11/05 1900 13 NR NR

07/13/05 0915 NR 19 79

15 Reedy Creek at U.S. Highway 129 near Ocilla 02316217 07/16/03 0745 18 11 78

08/13/03 1345 21 15 90

09/24/03 1340 18 14 62

16 Warrior Creek near Sumner 02317870 07/15/03 0750 13 18 50

08/12/03 0715 18 25 65

54 Results of Analyses of the Fungicide Chlorothalonil, Its Degradation Products, and Other Selected Pesticides
Table 16. Concentrations of dissolved organic carbon, suspended sediment, and percentage of silt- and clay-sized particles for water 

samples collected from 22 surface-water sampling sites in five Southern States, 2003–04.—Continued

[mg/L, milligrams per liter; NR, not measured; <, less than; mm, millimeters]

Map 

number 

(fig. 1)

Site name

Site identification 

number

Date of 

collection 

(month/

day/year)

Collection time 

(24-hour)

Dissolved 

organic 

carbon concentration 

(mg/L)

Suspendedsediment 

concentration (mg/L)

Percentage 

of silt- and 

clay-sized 

particles 

(<0.062 mm)

Georgia—Continued

16 Warrior Creek near Sumner—Continued 02317870 09/23/03 1020 14 29 62

07/08/04 1420 14 11 NR

09/06/04 1530 15 22 94

07/12/05 0950 11.0 NR NR

07/12/05 1700 12.0 46 81

17 Willacoochee Creek at Frank Road near Ocilla 02316134 07/16/03 1100 16 18 26

08/13/03 0930 18 22 73

09/24/03 1000 14 16 81

Oklahoma

18 Cobb Creek near Eakly 07325800 07/15/03 1030 2.7 NR NR

07/30/03 1200 5.0 NR NR

12/03/03 1015 2.9 NR NR

08/15/04 1630 4.7 74 73

08/28/04 1700 4.8 1,329 73

10/07/04 2130 4.9 1,297 85

19 Cobb Creek near Fort Cobb 07326000 07/15/03 1430 3.3 NR NR

12/03/03 1400 3.5 NR NR

08/15/04 1930 3.9 27 94

08/30/04 1300 3.8 30 85

10/12/04 1230 3.8 14 94

Texas

20 Beaver Creek near Electra 07312200 07/18/03 1415 6.5 NR NR

08/30/03 1305 6.6 NR NR

21 Sabana River near DeLeon 08099300 07/09/03 1240 5.0 NR NR

09/03/03 1030 8.4 NR NR

12/11/03 1130 4.7 NR NR

22 San Miguel Creek near Tilden 08206700 07/15/03 1050 7.9 NR NR

07/17/03 0910 10 NR NR

09/04/03 1100 12 NR NR

Supplemental Information  55
Table 17. Results of analysis of streamflow, gage height, and physical properties for water samples collected from 22 surface-water 

sampling sites in five Southern States, 2003–04. 

[ft3/s, cubic feet per second; ft, feet; μS/cm, microsiemens per centimenter at 25 degrees Celsius; oC, degrees Celsius; mg/L, milligrams per liter; NR, not measured]

Map 

number 

(fig. 1)

Site name

Site identification 

number

Date of 

collection 

(month/

day/year)

Collection time 

(24-hour)

Streamflow 

(ft3/s) 

Gage 

height 

(ft)

Specific 

conductance 

(μS/cm)

pH 

(standard 

units)

Water 

temperature (o

C)

Dissolved 

oxygen 

(mg/L)

Alabama

1 Big Creek at State 

Highway 203 near 

Rehobeth

02358765 06/25/03 1220 NR NR 67 6.9 NR NR

08/06/03 1140 45 NR 66 6.5 NR NR

09/17/03 1220 17 NR 65 6.6 NR NR

2 Cedar Creek at East 

Cook Road near 

Pansey

02343848 06/26/03 1210 16 NR 154 7.6 NR NR

08/04/03 1105 19 NR 140 7.1 NR NR

09/15/03 1545 19 NR 150 7.4 NR NR

06/15/04 1250 22 21.6 135 7.2 24 10

09/17/04 1220 25 21.4 117 7.2 24 7.6

3 Cowarts Creek above 

Cottonwood

0235878075 06/26/03 1515 29 NR 158 7.1 NR NR

08/05/03 0900 110 NR 105 6.9 NR NR

09/16/03 1225 58 NR 134 7.3 NR NR

4 Cowarts Creek near 

Love Hill

0235878055 06/25/03 1730 21 NR 176 7.6 NR NR

08/05/03 1300 46 NR 127 7.1 NR NR

09/16/03 1550 25 NR 155 7.4 NR NR

5 Spring Creek at 

County Road 55 

near Geneva

02365100 06/25/03 0810 48 NR 52 6.6 NR NR

08/06/03 0810 81 NR 48 6.2 NR NR

09/17/03 0900 39 NR 48 6.3 NR NR

Florida

6 Moore Creek near 

Chumuckla

02375800 06/23/03 1125 28 NR 45 6.3 NR NR

07/29/03 1215 27 NR 45 5.9 NR NR

09/25/03 1200 26 NR 95 5.8 NR NR

7 Pond Creek near 

Milton

02370700 06/23/03 1500 113 NR 25 5.0 NR NR

07/29/03 1435 114 NR 22 4.9 NR NR

09/24/03 1400 72 NR 34 5.0 NR NR

06/14/04 1310 70 3.2 34 5.2 22 7.5

09/23/04 0830 NR 15.3 29 5.8 22 6.5

56  Results of Analyses of the Fungicide Chlorothalonil, Its Degradation Products, and Other Selected Pesticides
Table 17. Results of analysis of streamflow, gage height, and physical properties for water samples collected from 22 surface-water 

sampling sites in five Southern States, 2003–04.—Continued

[ft3/s, cubic feet per second; ft, feet; μS/cm, microsiemens per centimenter at 25 degrees Celsius; oC, degrees Celsius; mg/L, milligrams per liter; NR, not 

measured]

Map 

number 

(fig. 1)

Site name

Site identification 

number

Date of 

collection 

(month/

day/year)

Collection time 

(24-hour)

Streamflow 

(ft3/s) 

Gage 

height 

(ft)

Specific 

conductance 

(μS/cm)

pH 

(standard 

units)

Water 

temperature (o

C)

Dissolved 

oxygen 

(mg/L)

Florida—Continued

8 Russ Mill Creek at 

Union Road near 

Cottondale

02358778 06/24/03 1330 15 NR 273 7.8 NR NR

08/05/03 1640 20 NR 244 7.4 NR NR

09/16/03 0825 9 NR 277 7.6 NR NR

9 West Fork Big Coldwater Creek near 

Allentown

02370400 06/24/03 0900 318 NR 35 5.7 NR NR

07/30/03 0800 227 NR 36 5.3 NR NR

09/25/03 0845 198 NR 77 5.4 NR NR

Georgia

10 Big Creek at Crystal 

Lake Road near 

Irwinville

2315919 07/16/03 1340 5 1.0 60 6.2 26 5.2

08/13/03 0710 82 4.0 59 5.9 26 5.7

09/24/03 0715 3 1.0 73 6.2 22 4.8

11 Black Creek near 

Blitchton

2202600 07/14/03 1020 92 5.0 56 4.7 25 3.8

08/11/03 0945 2,329 10.7 55 4.4 24 5.2

09/08/03 0900 807 8.0 56 4.7 NR NR

09/08/03 0915 811 8.0 53 4.7 NR NR

09/08/03 0930 807 8.0 53 4.7 NR NR

09/08/03 0945 811 8.0 52 4.8 NR NR

09/08/03 1000 811 8.0 53 4.7 NR NR

09/08/03 1015 811 8.0 52 4.7 NR NR

09/08/03 1030 811 8.0 52 4.7 NR NR

09/08/03 1045 816 8.0 51 4.7 NR NR

09/08/03 1100 811 8.0 52 4.6 NR NR

09/08/03 1115 811 8.0 52 4.7 NR NR

09/08/03 1130 811 8.0 51 4.7 NR NR

09/08/03 1145 811 8.0 51 4.7 NR NR

09/22/03 1230 32 3.5 57 4.6 24 4.0

10/18/03 1820 66 4.0 59 5.0 NR NR

10/18/03 1920 75 4.0 57 5.0 NR NR

10/18/03 1950 77 4.0 58 5.0 NR NR

10/18/03 2030 78 4.0 58 5.0 NR NR

06/23/04 0630 42 4.0 NR NR NR NR

Supplemental Information  57
Table 17. Results of analysis of streamflow, gage height, and physical properties for water samples collected from 22 surface-water 

sampling sites in five Southern States, 2003–04.—Continued

[ft3/s, cubic feet per second; ft, feet; μS/cm, microsiemens per centimenter at 25 degrees Celsius; oC, degrees Celsius; mg/L, milligrams per liter; NR, not 

measured]

Map 

number 

(fig. 1)

Site name

Site identification 

number

Date of 

collection 

(month/

day/year)

Collection time 

(24-hour)

Streamflow 

(ft3/s) 

Gage 

height 

(ft)

Specific 

conductance 

(μS/cm)

pH 

(standard 

units)

Water 

temperature (o

C)

Dissolved 

oxygen 

(mg/L)

Georgia—Continued

11 Black Creek near 

Blitchton—

Continued

2202600 06/24/04 0915 57 4.0 63 5.4 25 6.1

09/06/04 0940 31 3.5 NR NR NR NR

09/07/04 0340 59 4.0 NR NR NR NR

12 Bridge Creek at James 

King Road near 

Doerun

2327314 07/15/03 1115 NR 7.0 92 6.6 24 5.3

08/12/03 1000 57 9.0 73 6.5 24 5.7

09/23/03 0800 30 8.0 88 6.4 21 4.8

07/08/04 1900 30 9.0 57 6.7 25 5.9

09/06/04 1345 2 8.0 93 7.8 24 3.6

13 Coheelee Creek at 

River Road near 

Hilton

2343410 06/26/03 0815 12 NR 61 7.2 NR NR

08/04/03 1435 141 NR 40 6.0 NR NR

09/15/03 1220 13 NR 56 6.9 NR NR

06/15/04 1510 36 20.9 55 6.5 24 11

09/17/04 1530 191 19.5 39 6.2 25 6.4

14 Little Abrams Creek 

at GA Highway 313 

near Doles

2350522 07/15/03 1500 NR 1.0 83 6.2 26 2.8

08/12/03 1300 4 1.0 77 6.1 24 3.6

09/23/03 1350 1 1.0 69 6.0 24 2.4

07/08/04 1035 11 1.0 78 5.9 24 3.6

09/06/04 1830 3 1.0 71 4.7 25 7.8

15 Reedy Creek at U.S. 

Highway 129 near 

Ocilla

2316217 07/16/03 0745 9 9.0 86 6.3 24 2.9

08/13/03 1345 374 11.8 62 6.0 25 5.7

09/24/03 1340 2 9.0 110 6.4 22 1.5

16 Warrior Creek near 

Sumner

2317870 07/15/03 0750 7 6.0 103 6.7 24 5.2

08/12/03 0715 417 9.7 61 6.2 24 5.7

09/23/03 1020 169 8.0 60 6.3 23 5.6

07/08/04 1420 63 7.0 68 6.7 25 5.1

09/06/04 1530 9 5.0 65 8.0 24 5.1

17 Willacoochee Creek 

at Frank Road near 

Ocilla

02316134 07/16/03 1100 12 1.0 127 6.6 26 5.6

08/13/03 0930 288 3.0 79 6.2 24 4.2

09/24/03 1000 9 1.0 138 6.8 23 4.6

58  Results of Analyses of the Fungicide Chlorothalonil, Its Degradation Products, and Other Selected Pesticides
Table 17. Results of analysis of streamflow, gage height, and physical properties for water samples collected from 22 surface-water 

sampling sites in five Southern States, 2003–04.—Continued

[ft3/s, cubic feet per second; ft, feet; μS/cm, microsiemens per centimenter at 25 degrees Celsius; oC, degrees Celsius; mg/L, milligrams per liter; NR, not 

measured]

Map 

number 

(fig. 1)

Site name

Site identification 

number

Date of 

collection 

(month/

day/year)

Collection time 

(24-hour)

Streamflow 

(ft3/s) 

Gage 

height 

(ft)

Specific 

conductance 

(μS/cm)

pH 

(standard 

units)

Water 

temperature (o

C)

Dissolved 

oxygen 

(mg/L)

Oklahoma

18 Cobb Creek near 

Eakly

07325800 07/15/03 1030 16 4.0 770 7.6 25 8.6

07/30/03 1200 11 4.0 NR NR NR NR

12/03/03 1015 12 4.0 842 8.1 NR NR

08/28/04 1700 200 7.0 948 7.6 26 5.8

10/07/04 2130 47 5.0 423 7.6 18 8.1

19 Cobb Creek near Fort 

Cobb

07326000 07/15/03 1430 .02 NR 546 7.5 29 8.4

12/03/03 1400 4 4.0 580 7.4 NR NR

08/30/04 1300 4 4.0 523 7.8 22 6.9

10/12/04 1230 3 4.0 526 7.9 16 8.5

Texas

20 Beaver Creek near 

Electra

07312200 07/18/03 1415 5 8.0 3,760 8.1 33 7.4

08/30/03 1305 110 10.5 2,290 7.7 NR NR

21 Sabana River near 

DeLeon

08099300 07/09/03 1240 1 2.0 1,205 7.7 27 5.5

09/03/03 1030 2 2.0 346 7.4 NR NR

12/11/03 1130 2 2.0 929 8.1 NR NR

22 San Miguel Creek near 

Tilden

08206700 07/15/03 1050 4 2.0 1,640 8.1 29 5.7

07/17/03 0910 1,230 12.3 234 7.8 26 4.5

09/04/03 1100 60 4.0 NR NR NR NR

Supplemental Information  59
Prepared by Lawrence Publishing Service Center.

Edited by Lanna Combs.

Illustrations and cover design by Jeff Hartley and Mike Kemppainen.

Layout and design by Kristi Hartley.

For more information concerning the research described in this report, 

contact:

U.S. Geological Survey

4821 Quail Crest

Lawrence, KS 66049–3839

(785) 842–9909

http://ks.water.usgs.gov
Printed on recycled paper

Scribner and others—Results of Analyses of the Fungicide Chlorothalonil, Its Degradation Products, and Other Selected 

Pesticides at 22 Surface-Water Sites in Five Southern States, 2003–04 —Open-File Report 2006−1207