U.S. Department of the Interior

U.S. Geological Survey

Open-File Report 2012–1128 

Prepared in cooperation with the 

U.S. Department of the Army Environmental and Natural Resources Management 

Office of the U.S. Army Signal Center and Fort Gordon

Assessment of Soil-Gas and Groundwater Contamination 

at the Gibson Road Landfill, Fort Gordon, Georgia, 2011
Cover photo shows access road along northwestern side 

of wetland and partially cleared land between wetland and 

Gibson Road landfill. Photo by W. Fred Falls, USGS.;
Assessment of Soil-Gas and Groundwater 

Contamination at the Gibson Road Landfill, 

Fort Gordon, Georgia, 2011 

By W. Fred Falls, Andral W. Caldwell, Wladmir G. Guimaraes, W. Hagan Ratliff, 

John B. Wellborn, and James E. Landmeyer 

Prepared in cooperation with the 

U.S. Department of the Army Environmental and Natural Resources Management 

Office of the U.S. Army Signal Center and Fort Gordon

Open-File Report 2012–1128

U.S. Department of the Interior

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

KEN SALAZAR, Secretary

U.S. Geological Survey

Marcia K. McNutt, Director

U.S. Geological Survey, Reston, Virginia: 2012

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reproduce any copyrighted materials contained within this report.

Suggested citation:

Falls, W.F., Caldwell, A.W., Guimaraes, W.G., Ratliff, W.H., Wellborn, J.B., and Landmeyer, J.E., 2012, Assessment 

of soil-gas and groundwater contamination at the Gibson Road landfill, Fort Gordon, Georgia, 2011: U.S. Geological 

Survey Open-File Report 2012–1128, 27 p. (also available at http://pubs.usgs.gov/ofr/2012/1128/).
iii

Contents 

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

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

Puurpose and Scope .......................................................................................................................2

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

Gibson Road Landfill....................................................................................................................2

Soil-Gas and Groundwater Assessment..................................................................................5

Methods...........................................................................................................................................................5

Results .............................................................................................................................................................9

Quality Assurance and Quality Control .............................................................................................9

Soil-Gas Assessment ...........................................................................................................................9

Groundwater Assessment.................................................................................................................14

Summary........................................................................................................................................................15

References Cited..........................................................................................................................................16

Figures

 1. Map showing the locations of Fort Gordon, the Gibson Road landfill, 

the monitoring wells, and the study area, Richmond County, Georgia, 2011 ............................3 

 2. Map showing the locations of passive samplers for the soil-gas and 

groundwater assessments at the Gibson Road landfill, 

 Richmond County, Georgia, 2011...................................................................................................4

 3. Photographs showing land characteristics of the study area to the southeast 

of the Gibson Road landfill including the access road along the northwestern 

side of the wetland and the partially cleared land near the access road, the 

wooded wetland, the partially wooded area near the southeastern side of the 

landfill, and the gully near the southeastern side of the landfill, Fort Gordon, 

Richmond County, Georgia, 2011...................................................................................................6

 4. Photographs showing a passive sampler prior to installation and in an 

air-tight vial as received from the laboratory for deployment and shipped 

to the laboratory for analysis ........................................................................................................7

 5. Photographs showing installation of a passive sampler for a soil-gas sampling 

site, including drilling a borehole in the soil with a stainless steel drill bit attached 

to a cordless drill, attaching one end of a string to a sampler and the other end to 

a cork plug, inserting the sampler into the borehole, and sealing the borehole with 

the cork plug to keep out surface contaminants.........................................................................8

6–9. Photographs and aerial site maps showing locations and identification numbers 

for passive samplers deployed in the soil and the monitoring wells, and: 

 6. Ranges of mass in the soil gas and concentration in groundwater for total 

petroleum hydrocarbons (TPH) at the Gibson Road landfill, Fort Gordon, 

Georgia, July 25–29, July 26–29, July 29–August 3, and August 8, 2011. .........................10

7. Ranges of combined undecane, tridecane, and pentadecane (C11, C13, and C15) 

as diesel mass in soil gas, and as diesel concentration in groundwater at 

the Gibson Road landfill, Fort Gordon, Georgia, July 25–29, July 26–29, 

July 29–August 3, and August 8, 2011......................................................................................11
iv

8. Ranges for combined benzene, toluene, ethylbenzene, and xylene as 

BTEX mass in the soil gas, and as BTEX concentration in groundwater 

at the Gibson Road landfill, Fort Gordon, Georgia, July 28–29, 

July 29–August 3, and August 8, 2011......................................................................................12

9. Ranges for naphthalene, chloroform and perchloroethene as masses 

in the soil gas, and concentrations of chlorinated compounds in 

groundwater at the Gibson Road landfill, Fort Gordon, Georgia, 

July 28–29, July 29–August 3, and August 8, 2011 .................................................................13

Tables 

1. Gore identification numbers and location information for passive samplers 

deployed and recovered in the soil-gas assessment from July 25–29, 

July 26–29, and July 29–August 3, 2011, and groundwater assessment 

on August 8, 2011, at the Gibson Road landfill study area, Fort Gordon, Georgia............ 18–19

2. Masses for volatile and semivolatile organic compounds and polycyclic 

aromatic hydrocarbons detected in passive samplers deployed and 

recovered during the soil-gas assessment in the Gibson Road landfill 

study area, Fort Gordon, Georgia, July 25–29, July 26–29, and 

July 29–August 3, 2011...........................................................................................................20–25

3. Concentrations of volatile and semivolatile organic compounds and 

polycyclic aromatic hydrocarbons detected in passive samplers 

deployed and recovered in the water column of monitoring wells in 

Gibson Road landfill study area, Fort Gordon, Georgia, August 8, 2011 ............................. 26–27
v

Conversion Factors and Datums 

Multiply By To obtain

Length

inch (in) 2.54 centimeter (cm)

inch (in) 25.4 millimeter (mm)

foot (ft) 0.3048 meter (m)

mile (mi) 1.609 kilometer (km)

Area

acre 4,047 square meter (m2)

acre 0.4047 hectare (ha)

acre 0.4047 square hectometer (hm2) 

acre 0.004047 square kilometer (km2)

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

Soil-gas units

μg microgram 

μg/L micrograms per liter 

Acronyms and Abbreviation

bdl below detection level

BTEX benzene, toluene, ethylbenzene, and xylene (total)

C11, C13, and C15 undecane, tridecane, and pentadecane (total)

MDL method detection level

MTBE methyl tert-butyl ether

PAH polycyclic aromatic hydrocarbon

PCE perchloroethene (also known as perchloroethylene and tetrachloroethene)

SVOC semivolatile organic compound

TCE trichloroethene (also known as trichloroethylene)

TPH total petroleum hydrocarbons

USEPA U.S. Environmental Protection Agency

USGS U.S. Geological Survey

VOC volatile organic compound
vi
Abstract 

Soil-gas and groundwater assessments were conducted 

at the Gibson Road landfill in 2011 to provide screening-level 

environmental contamination data to supplement the data 

collected during previous environmental studies at the landfill. 

Passive samplers were used in both assessments to detect 

volatile and semivolatile organic compounds and polycyclic 

aromatic hydrocarbons in soil gas and groundwater.

A total of 56 passive samplers were deployed in the 

soil in late July and early August for the soil-gas assessment. 

Total petroleum hydrocarbons (TPH) were detected at masses 

greater than the method detection level of 0.02 microgram 

in all samplers and masses greater than 2.0 micrograms in 

13 samplers. Three samplers located between the landfill and a 

nearby wetland had TPH masses greater than 20 micrograms. 

Diesel was detected in 28 of the 56 soil-gas samplers. 

Undecane, tridecane, and pentadecane were detected, but 

undecane was the most common diesel compound with 

23 detections. Only five detections exceeded a combined 

diesel mass of 0.10 microgram, including the highest mass 

of 0.27 microgram near the wetland. Toluene was detected in 

only five passive samplers, including masses of 0.65 microgram near the wetland and 0.85 microgram on the southwestern side of the landfill. The only other gasoline-related 

compound detected was octane in two samplers. Naphthalene 

was detected in two samplers in the gully near the landfill 

and two samplers along the southwestern side of the landfill, 

but had masses less than or equal to 0.02 microgram. Six 

samplers located southeast of the landfill had detections of 

chlorinated compounds, including one perchloroethene detection (0.04 microgram) and five chloroform detections (0.05 to 

0.08 microgram).

Passive samplers were deployed and recovered on 

August 8, 2011, in nine monitoring wells along the southwestern, southeastern and northeastern sides of the landfill and 

downgradient from the eastern corner of the landfill. Six of the 

nine samplers had TPH concentrations greater than 100 micrograms per liter. TPH concentrations declined from 320 micrograms per liter in a sampler near the landfill to 18 micrograms 

in a sampler near the wetland. Five of the samplers had 

detections of one or more diesel compounds but detections 

of individual diesel compounds had concentrations below a 

method detection level of 0.01 microgram per liter. Benzene 

was detected in three samplers and exceeded the national 

primary drinking-water standard of 5 micrograms per liter set 

by the U.S. Environmental Protection Agency. The concentrations of benzene, and therefore BTEX, were 6.1 micrograms 

per liter in the sampler near the eastern corner of the landfill, 

27 micrograms per liter in the sampler near the wetland, and 

37 micrograms per liter in the sampler at the southern corner 

of the landfill.

Nonfuel-related compounds were detected in the four 

wells that are aligned between the eastern corner of the landfill 

and the wetland. The sampler deployed nearest the eastern 

corner of the landfill had the greatest number of detected 

organic compounds and had the only detections of two 

trimethylbenzene compounds, naphthalene, 2-methyl naphthalene, and 1,4-dichlorobenzene. The two upgradient samplers 

had the greatest number of chlorinated compounds with five 

compounds each, compared to detections of four compounds 

and one compound in the two downgradient samplers. All four 

samplers had detections of 1,1-dichloroethane which ranged 

from 42 to 1,300 micrograms per liter. Other detections of 

chlorinated compounds included trichloroethene, perchloroethene, cis-1,2-dichloroethene, 1,1,1-trichloroethane and 

chloroform.

Assessment of Soil-Gas and Groundwater Contamination 

at the Gibson Road Landfill, Fort Gordon, Georgia, 2011

By W. Fred Falls1, Andral W. Caldwell1, Wladmir G. Guimaraes1, W. Hagan Ratliff2, 

John B. Wellborn3, and James E. Landmeyer1

______________________

1

 U.S. Geological Survey, Columbia, South Carolina.

2

 Environmental Branch, Fort Gordon, Georgia.

3

 Environmental and Natural Resources Division, Fort Gordon, Georgia.
2 Soil-gas and groundwater contamination at the Gibson Road landfill, Fort Gordon, Georgia, 2011

Introduction

Fort Gordon is a U.S. Department of the Army facility 

located in east-central Georgia, approximately 10 miles 

southwest of Augusta, Georgia (fig. 1). Several areas at Fort 

Gordon have been used for the disposal of waste related to 

the operation of the fort, including the currently (2012) active 

Gibson Road landfill near Sandy Run Creek in the central 

part of Fort Gordon. Volatile organic compounds have been 

detected during previous investigations in water samples from 

the groundwater-monitoring wells located inside and outside 

the perimeter fence of the landfill (Priest and McSwain, 2002).

Soil-gas and groundwater assessments were conducted 

at the Gibson Road landfill in 2011 to provide screening-level 

environmental contamination data to supplement the data 

collected during previous environmental studies at the landfill 

(fig. 2). The soil-gas and groundwater data of the 2011 assessments are not quantitative as were previously reported waterquality data for water samples, but the sampling sites in the 

soil-gas assessment are more numerous than the existing monitoring wells and have a broader coverage of the area immediately outside the perimeter fence surrounding the landfill 

and in the downslope area between the landfill and a nearby 

unnamed wetland. Passive samplers also were deployed in 

the water column of nine of the existing monitoring wells to 

determine the organic compounds in the groundwater.

The assessment of potential environmental effects at 

the landfill is warranted, because the Gibson Road landfill is 

located in the outcrop area of the Dublin and Midville aquifer 

systems, which are water-supply sources for drinking-water 

wells in the nearby towns of Augusta and Hephzibah, Georgia 

(Williams, 2007; fig. 1). The assessments are further warranted 

because the Gibson Road landfill is located near a wetland 

that drains to Sandy Run Creek (fig. 1). Contaminants in 

groundwater, surface water, and soil derived from the landfill 

could affect the local ecology and water quality of the wetland 

and Sandy Run Creek, and potentially be transported off Fort 

Gordon into the regional surface-water drainage system.

Purpose and Scope

The U.S. Geological Survey assessed the presence of 

volatile and semivolatile organic compounds (VOCs and 

SVOCs) and polycyclic aromatic hydrocarbons (PAHs) in 

soil gas and groundwater in the land surrounding the Gibson 

Road landfill in July and August 2011 (fig. 2). The assessment 

was completed in cooperation with the U.S. Department of 

the Army Environmental and Natural Resources Management Office of the U.S. Army Signal Center and Fort Gordon, 

Georgia. 

The sampling sites for the soil-gas assessment were 

chosen to determine the distribution of VOCs, SVOCs, and 

PAHs around the landfill and between the landfill and the 

wetland, because of the close proximity of the landfill to 

the wetland (fig. 2). A few additional passive samplers were 

deployed in the field to the southwest of the landfill to assess 

the presence of VOCs, SVOCs, and PAHs in the soil between 

the landfill and Sandy Run Creek.

Nine of the thirteen existing wells used to monitor 

groundwater levels and collect groundwater samples were 

sampled with the same passive sampler used at the soil-gas 

sampling sites to determine the presence of organic compounds in the groundwater along the southwestern and 

northeastern sides of the landfill and southeast of the landfill 

in the direction of the wetland (fig. 2). The results of the passive samplers are compared to results for soil-gas samplers 

deployed adjacent to seven of the wells and to water-quality 

results from the wells reported in a previous investigation 

(Priest and McSwain, 2002).

This report provides analytical results for the soil-gas and 

groundwater samplers and maps showing the locations of the 

most commonly detected contaminants identified in the study 

area. This report also provides a map showing the locations 

of less common detections, such as chlorinated compounds, 

trimethylbenzene, and naphthalene.

Description of the Study Area

Fort Gordon is located south of the Fall Line in the 

northern part of the Coastal Plain Physiographic Province near 

Augusta, Georgia (fig. 1). Fort Gordon is underlain by late 

Cretaceous and Tertiary geologic strata and is characterized by 

soils, alluvial sediments, and geologic exposures of unconsolidated sands and semiconsolidated sandstones, and layers of 

clay that include kaolinite (Hetrick, 1992; Gregory and others, 

2001).

Average annual precipitation in the Fort Gordon/Augusta, 

Georgia, area is approximately 44.5 inches (in.) (Southeast 

Regional Climate Center at the University of North Carolina, 

Chapel Hill, N.C., website accessed February 17, 2012, for 

Augusta WSO Airport, Georgia 090495, http://nc-climate.

ncsu.edu/cronos/normals.php?station=090495). With the 

porous sandy soil and the hilly topography in the study area, 

perennial creeks and streams in the area of Fort Gordon 

receive an ample supply of groundwater discharge to maintain 

streamflows during times of normal precipitation (Faye and 

Mayer, 1990; Atkins and others, 1996). During the summer 

of 2011, however, there was no standing water observed in 

the wetland, which may reflect the seasonality of intermittent 

flow in parts of the wetland and the lower than normal annual 

precipitation of 28.6 and 28.2 in. in the Augusta area in 2010 

and 2011, respectively.

Gibson Road Landfill

The Gibson Road landfill is an approximately 35-acre 

site located on the southern sides of Gibson Road and Sawmill 

Road (unpaved) and occupies a topographically high area 
Introduction 3

Base from U.S. Army 

Albers equal-area conic projection 

Standard parallels 29°30’N and 45°30’N 

Central meridian -96°00’00”

Gibson Road Landfill

N

82°14'50" 82°14'40" 82°14'30" 82°14'20" 82°14'10"

82°14'50" 82°14'40" 82°14'30" 82°14'20" 82°14'10"

33°22'10"

33°22'

33°21'50"

33°22'10"

33°22'

33°21'50"

Reservoir

Wetland

N

COLUMBIA CO.

MCDUFFIE 

CO.

88

20 520

1

221

223

78

MCDUFFIE 

CO.

RICHMOND CO.

BURKE CO.

Augusta

Hephzibah

0 1 2 3

0 1 2 3

4

4

5 MILES

5 KILOMETERS

78

Base from 1:100,000-scale 

U.S. Geological Survey digital line graph

Brier

Creek

Spirit Cree

So

k

uth Prong Creek

Boggy Gut Creek

JEFFERSON CO.

RICHMOND CO.

San Run Creek

dy

Gibson Road Landfill

Wetland

EXPLANATION

 Monitoring well

Reservoir

Study 

area

Augusta

Coastal Plain

GEORGIA

Piedmont

Blue Ridge

Cumberland 

Plateau, Valley, 

and Ridge

Fall Line

Study area 

Fort Gordon 

EXPLANATION

32°26’15”

32°18’45”

82°18’45” 82°11’15”

ACCESS ROAD

SAWMILL ROAD

GIBSON ROAD

ACCESS ROAD

DIRT ROAD

gully

Location of

 sampling sites

0 500 1,000 FEET

0 100 200 300 METERS

Figure 1. Locations of Fort Gordon, the Gibson Road landfill, the monitoring wells, and the study area, Richmond County, Georgia, 2011.
4 Soil-gas and groundwater contamination at the Gibson Road landfill, Fort Gordon, Georgia, 2011

Base from U.S. Army 

Albers equal-area conic projection 

Standard parallels 29 ̊20’N and 45 ̊30’N 

Central meridian -96 ̊00’00”

Wetland

0 500 1,000 FEET

0 100 200 300 METERS

GIBSON ROAD

Gibson Road 

Landfill

Gibson Road 

Landfill

Wetland

DIRT ROAD

ACCESS ROAD

667399

667419

667418

667417

667416

667420

667421

667415

667414

667413

667402

667401

667403

667404

667405

667406

667407

667408

667409

667410

667411

667412

667424

667425

667426

667427

667423

667397

667398

662573

667422

667393

667395 667394

667396

667400

662559

662560

662561

662562

662563

662564

662565

662566

662567

662568

662569

662570

662571

662572

662579

662578

662577

662576

662575

662574

667399

667419

667418

667417

667416

667420

667421

667415

667414

667413

667402

667401

667403

667404

667405

667406

667407

667408

667409

667410

667411

667412

667424

667425

667426

667427

667423

667397

667398

667422

667393

667395 667394

667396

662573

662559

662560

662561

662562

662563

662564

662565

662566

662567

662568

662569

662570

662571

662572

662579

662578

662577

662576

662575

662574

667400

667441

667433

667434

667435

667438

667436

667437

667439

667440

667433

667434

667441

667435

667438

667436

667437

667439

667440

82°14’40” 82°14’30” 82°14’20”

82°14’40” 82°14’30” 82°14’20”

32°22’10”

32°22’

32°21’50”

32°22’10”

32°22’

32°21’50”

EXPLANATION

Groundwater sampler and sampler number

667408 Soil-gas sampler and sampler number

667440

N

Figure 2. Locations of passive samplers for the soil-gas and groundwater assessments at the Gibson Road landfill, 

Richmond County, Georgia, 2011.
Methods 5

relative to the wetland to the southeast, Sandy Run Creek to 

the southwest, and a small reservoir to the northwest (fig. 1). 

The landfill is fenced and has a gate to regulate access. 

Unpaved access roads parallel the perimeter fence inside and 

outside the landfill that enables access to the monitoring wells.

The landfill was issued an operating permit in 1985 and 

operated continuously as an unlined landfill for 26 years prior 

to the 2011 investigation (Priest and McSwain, 2002). Disposal of household waste began at the northeastern end of the 

landfill in 1985 and continued into the middle of the landfill 

through the mid-1990s. Since the mid-1990s, the southwestern 

part of the landfill has received mainly construction and demolition waste. The northeastern and central parts of the landfill 

were capped with soil to control infiltration of precipitation 

and grassed to control erosion, but the southwestern quarter of 

the landfill is still (2012) open and continues to receive waste 

(fig. 1).

Overland flow of rainwater inside the fenced area drains 

across the surface of the capped part of the landfill to a 1-acre 

retention pond on the southeastern side of the landfill inside 

the perimeter fence (fig. 1). If enough water accumulates in the 

retention pond, water drains into an overflow pipe in the center 

of the pond and is discharged to the adjacent woodland outside 

the perimeter fence on the southeastern side of the landfill. The 

southwestern quarter of the landfill receives some overland 

flow from adjacent parts of the landfill inside the fence and is 

open to precipitation events. 

Monitoring wells were installed along the access roads 

inside and outside the perimeter fence for a water-quality 

monitoring program started in 1985 (fig. 1). Additional wells 

were installed in 1995 in the wooded area downslope of the 

eastern corner of the perimeter fence (Priest and McSwain, 

2002, fig. 1). Groundwater levels were measured in the monitoring wells during June and November 1999. The general 

direction of groundwater flow is from the northwest to the 

southeast across the landfill and from the landfill toward the 

wetland. Organic contaminants were detected in groundwater 

samples collected in 1998 and 1999 from monitoring wells on 

the northwestern side of the landfill along Gibson Road, but 

were detected at higher concentrations for methylene chloride, 

1,1-dichloroethane, and 1,1,1-trichloroethane in a well outside 

the eastern (downgradient) corner of the perimeter fence 

(Priest and McSwain, 2002).

Soil-Gas and Groundwater Assessment

The study area chosen for the soil-gas assessment 

included land on all four sides of the landfill outside the 

perimeter fence, but mostly consisted of the land between the 

eastern (downgradient) side of the landfill and the access road 

adjacent to the wetland (fig. 2). The study area was expanded 

to include the field to the southwest of the landfill but does not 

include the land inside the landfill or wetland, or the land to 

the northwest of Gibson Road. The landfill and soil-gas study 

area, excluding the wetland, occupies approximately 106 acres 

at Fort Gordon.

The land between the landfill and the wetland is sloped to 

the east and southeast and is described as heavily wooded in a 

previous study (Priest and McSwain, 2002). Prior to the 2011 

assessments, however, much of this land between the landfill 

and the wetland was partially cleared of trees and underbrush. 

The access road along the edge of the wetland delineates a 

boundary between the sparsely wooded (cleared) land to the 

northwest and west of the access road and the still wooded 

wetland (figs. 1; 3A, B). Farther upslope toward the landfill, 

trees were selectively cleared to thin the woodland but this 

area generally had more trees and underbrush during the 2011 

assessment and is steeper than the land closer to the wetland 

(fig. 3C). An elongated topographic depression (gully) to the 

southeast is cut into the land surface closer to the eastern side 

of the landfill and was not disturbed by the clearing of trees 

(figs. 1 and 3D).

Passive samplers in the soil-gas assessment were 

deployed outside the perimeter fence along all four sides of 

the landfill, between the eastern sides of the landfill and the 

access road along the edge of the wetland, and in the adjacent field to the southwest of the landfill (fig. 2). Most of the 

sampling locations were chosen to create a fairly even spacing 

of the samplers around and downgradient from the landfill. 

Five of the samplers, however, were intentionally deployed 

closer together in and adjacent to the gully to evaluate the 

presence of contaminants associated with this topographically 

low feature. Four samplers also were deployed 350 to 600 feet 

(ft) southwest of the landfill to assess the potential for VOCs, 

SVOCs, and PAHs in the field adjacent to the landfill.

Nine of the thirteen monitoring wells were selected for 

the groundwater assessment using the passive samplers and 

represented only a partial coverage in the study area, relative 

to the passive samplers deployed in the soil-gas assessment 

(fig. 2). Only wells outside the perimeter fence of the landfill 

were considered for the study. The wells chosen for the assessment are located along the southwestern, southeastern, and 

northeastern sides of the landfill or in an area downgradient 

from the eastern corner of the landfill. Groundwater was collected from some of the wells during a previous study in 1998 

and 1999 by a commercial environmental company (Priest and 

McSwain, 2002).

Methods

Passive samplers were collected for soil-gas and groundwater assessments of potential organic compounds in the 

Gibson Road landfill study area (fig. 2; tables 1–3 at end of 

report). Passive samplers were deployed and collected in the 

unsaturated soil around and downgradient from the landfill and 

in the field adjacent to the southwest side of the landfill during 

late July and early August 2011, and in the water columns of 

nine existing monitoring wells outside the perimeter fence of 

the landfill on August 8, 2011. All samplers were analyzed 

by U.S. Environmental Protection Agency (USEPA)-verified 
6 Soil-gas and groundwater contamination at the Gibson Road landfill, Fort Gordon, Georgia, 2011

sampling technologies at the W.L .Gore & Associates Laboratory in Elkton, Maryland, from August 25–29, 2011, (U.S. 

Environmental Protection Agency, 1998; W.L. Gore & Associates, Inc., 2004; American Society for Testing and Materials, 

2006).

Samples for the soil-gas and groundwater assessments 

were collected at the Gibson Road landfill by using the 

GORETM passive vapor sampler, a commercially available 

passive sampler based on GORE-TEXTM membrane technology (U.S. Environmental Protection Agency, 1998; W.L. Gore 

& Associates, Inc., 2004). The passive sampler approach was 

approved for use at sites at Fort Gordon by the Hazardous 

Waste Management Branch, Georgia Environmental Protection Department, to collect screening-level data for contaminant assessments (William Powell, P.E., Environmental Engineer, Department of Defense Remediation Unit, oral commun., 

December 10, 2008).

The passive sampler consists of a proprietary adsorbent 

medium placed inside a shoestring-shaped GORE-TEXTM tube 

(fig. 4A). The proprietary medium can adsorb a wide variety of 

volatile and semivolatile organic compounds (VOCs/SVOCs), 

including chlorinated solvents such as trichloroethene (TCE) 

and perchloroethene (PCE; also known as tetrachloroethene); 

gasoline-range compounds such as benzene, toluene, ethylbenzene, and xylenes (collectively referred to as BTEX); the 

gasoline additive methyl tert-butyl ether (MTBE); diesel-range 

compounds such as undecane, tridecane, and pentadecane 

(collectively referred to as C11, C13, and C15); and polycyclic 

aromatic hydrocarbons (PAHs) such as naphthalene (U.S. 

Environmental Protection Agency, 1998).

Passive results can indicate the presence of particular 

organic compounds and are a rapid approach for environmental assessment of organic compounds (U.S. Environmental 

Protection Agency, 1998). The results do not, however, reveal 

if the detection was derived from free product, residual-phase 

A B

C D

Figure 3. Land characteristics of the study area to the southeast of the Gibson Road landfill, including: A, the access road along the 

northwestern side of the wetland and the partially cleared land near the access road; B, the wooded wetland; C, the partially wooded 

area near the southeastern side of the landfill; and D, the gully near the southeastern side of the landfill, Fort Gordon, Richmond County, 

Georgia, 2011.
Methods 7

compounds adsorbed on soil particles, vapors in the unsaturated zone, or the dissolved compound in shallow and deep 

groundwater (unless the passive soil-gas sampler is deployed 

in direct contact with water) (U.S. Environmental Protection 

Agency, 2000). 

In unsaturated soil, higher soil-gas mass in a sampler 

tends to be related to the presence of residual compounds 

or free product that is close to the land surface where the 

sampler is located (U.S. Environmental Protection, 1998). If 

such source material is located at greater depths, however, 

the soil-gas mass generally will be lower. A lower value near 

known sources may be due to various attenuation processes 

that affect the soil-gas mass prior to detection. In both cases, 

however, the passive vapor samplers indicate the presence of 

contaminants.

In the soil-gas study area, sample sites for the passive 

sampler were created with a stainless steel bit attached to a 

cordless drill (fig. 5). A 0.5-in-diameter bit was used to drill 

a 15-in-deep vertical borehole into the soil. A string was 

attached to a cork plug at one end and the passive sampler at 

the other end, and was used to lower and suspend the sampler 

in the borehole. The cork plug was used to seal the borehole at 

land surface to prevent surface water and ambient land-surface 

material from entering the borehole. The depth of 15 in. is 

similar to the depth recommended by the USEPA for soil-gas 

investigations (U.S. Environmental Protection Agency, 1998). 

Most of the passive samplers in the soil-gas assessment were 

deployed on July 25 and recovered on July 29, 2011, after 

4 days (96 hours) of exposure to the shallow soil gas. Samplers, including one (667421) next to the well sampled on the 

northeastern side of the landfill and two (667422 and 667423) 

deployed in the gully on the southeastern side of the landfill, 

were deployed on July 26 and recovered on July 29, 2011, 

after 3 days (72 hours). Four additional samplers (667424 

– 667427) were deployed near a dirt road in field adjacent to 

the southwest side of the landfill on July 29 and recovered on 

August 3, 2011, after 5 days (120 hours).

The same type of passive sampler used in the soil-gas 

study also was used in the groundwater assessment at the 

Gibson Road landfill. The wells were not developed specifically for the groundwater assessment, but had been developed 

before collection of groundwater samples for previous studies. 

The groundwater level in each well was checked with an 

electric water-level sensor to determine depth to static groundwater level. A sampler was attached to a weighted string and 

lowered to a depth of 5 ft below the static groundwater level in 

each well. The samplers were submerged in the water column 

for only 30 to 60 minutes because a previous investigation 

found that contaminants in groundwater can adsorb rapidly 

on the proprietary medium in a submerged sampler (U.S. 

Environmental Protection Agency, 2000; Guimaraes and others, 2011). All samplers in the groundwater assessment were 

deployed and collected on August 8, 2011.

Each passive sampler recovered in the field was placed 

in its original 20-milliliter (mL) air-tight vial provided by the 

laboratory and sent to a commercial laboratory (W.L. Gore 

& Associates, Inc.) for analysis (fig. 4B). For each period of 

deployment, 5 to 10 percent of the samplers were kept in the 

air-tight vials during the deployment and recovery of environmental samplers and were shipped back to the laboratory with 

the environmental samplers as trip blanks. 

All samplers were processed and analyzed at the 

laboratory by using a modification of USEPA method 

8260/8270 (U.S. Environmental Protection Agency, 2006). 

Prior to analysis, each sampler was processed in an automated 

thermal desorption unit to produce a gas sample. The gas 

sample was analyzed by a gas chromatograph equipped with 

mass-selective detectors. The laboratory analyzed method 

A B

Figure 4. A passive sampler A, prior to installation, 

and B, in air-tight vial as received from the laboratory 

for deployment and shipped to the laboratory for 

analysis.
8 Soil-gas and groundwater contamination at the Gibson Road landfill, Fort Gordon, Georgia, 2011

blanks for quality assurance and was in compliance with good 

laboratory practices and ISO Guide 25 (International Organization for Standardization, 1990). Results are reported as mass 

in micrograms (mg) for the soil-gas assessment and concentration in micrograms per liter (mg/L) for the groundwater 

assessment. Concentrations in water for each contaminant 

were calculated using the measured contaminant mass, sampler exposure time to the environment, and compound-specific 

solute uptake rates based on an average water temperature of 

20 degrees Celsius and a water depth of 5 ft (Dayna M. Cobb, 

Project Manager, W.L. Gore & Associates, Inc., written commun., September 12, 2011).

The laboratory results provided screening-level data for 

the assessment of 31 compounds. TPH is a laboratory-derived 

estimate based on the area under the chromatogram for all 

aliphatic hydrocarbons, including all gasoline-range (C4 to C10) 

and diesel-range (C10 to C20) aliphatic compounds. In addition, 

results of individual compounds were summed to calculate 

values for the combined mass in soil gas and combined concentrations in groundwater of benzene, toluene, ethylbenzene, 

and xylenes (aromatic gasoline-range compounds) as BTEX; 

undecane, tridecane, and pentadecane (C11, C13, and C15) 

as diesel; 1,2,4- and 1,3,5-trimethylbenzene (as trimethylbenzene); trans- and cis-1,2-dichloroethene (as 1,2-dichloroethene); and naphthalene and 2-methyl naphthalene (as 

naphthalene). 

The laboratory provided method detection levels (MDL) 

for each organic compound. The laboratory, however, did not 

provide MDLs for the five combined values because individual compounds summed as a combined value may have 

different MDLs. A combined value is considered estimated 

(E) if the measureable value for at least one of the individual 

compounds in the combined value is summed with at least one 

value reported as below its MDL. A value of 0.00 is the reporting format of W.L. Gore & Associates, Inc., and is used for a 

combined value if none of the individual compounds summed 

in the combined value were detected above MDLs and at least 

one of the individual compounds was reported as below detection level.

A B

C D

Figure 5. Installation of a passive sampler for a soil-gas sampling site, including: A, drilling a borehole in the soil with 

a stainless steel drill bit attached to a cordless drill; B, attaching one end of a string to a sampler and the other end to a 

cork plug; C, inserting the sampler into the borehole; and D, sealing the borehole with the cork plug to keep out surface 

contaminants.
Results 9

Results

The detections and the distribution of detections in the 

Gibson Road landfill study area are evaluated using environmental samplers 662559 to 662579 and 667393 to 667427 as 

the soil-gas assessment, and environmental samplers 667433 

to 667443 as the groundwater assessment (tables 2 and 3, 

respectively, at end of report). A passive sampler was deployed 

in the soil next to each of the wells in the groundwater assessment, except for two of the downgradient wells (samplers 

667435 and 667436). Results for these seven pairs of samplers 

are included in the description of the groundwater assessment. 

The results for the groundwater assessment also are compared 

to previously published water-quality results for the wells collected in 1998 and 1999 (Priest and McSwain, 2002).

Quality Assurance and Quality Control

The laboratory reported no detections of organic 

compounds in the method blanks analyzed with the samplers 

in the soil-gas and groundwater assessments and no detections 

in the five trip blanks (667428–667432) associated with the 

samplers in the soil-gas assessment (tables 2 and 3). The two 

trip blanks (667442 and 667443) carried to the field during the 

groundwater assessment, however, did have TPH detections, 

but the TPH concentrations were reported as below the TPH 

detection level of 8.3 mg/L. One of the trip blanks (667443) 

carried to the field during the groundwater assessment also had 

a detection of toluene at a concentration of 4.8 mg/L, which 

exceeded the toluene MDL of 4.1 mg/L. There were, however, 

no detections of toluene in the nine passive samplers for the 

groundwater assessment, and therefore, the environmental 

results for toluene did not have to be qualified (censored).

The detection of toluene in trip blank 667443 means that 

the combined concentration of BTEX in the trip blank also 

is reported as 4.8 mg/L. Three environmental samplers in the 

groundwater assessment had BTEX detections greater than the 

BTEX detection in the trip blank, but the BTEX detections in 

the environmental samplers were due to benzene, not toluene, 

ethylbenzene, or the xylene compounds. Benzene was not 

detected in the two trip blanks; therefore, the BTEX detection in the trip blank was not used to qualify (censor) the three 

BTEX detections in the groundwater assessment.

Soil-Gas Assessment

A total of 56 samplers were deployed for the soil-gas 

assessment in the Gibson Road landfill study area (fig. 2). 

The survey mostly identified detections of TPH and dieselrange compounds, but also identified the presence of BTEX 

(toluene), PCE, chloroform, and naphthalene in a few samples 

(table 2).

TPH mass exceeded the MDL of 0.02 mg in all 

56 samplers and was equal to or exceeded 2.0 mg in 13 of the 

56 samplers (fig. 6; table 2). The 13 TPH detections greater 

than 2.0 mg were found in samplers located along all sides 

of the landfill except along Gibson Road, which is upgradient from the landfill. TPH exceeded a mass of 20 mg in 

three samplers located between the landfill and the wetland. 

The TPH mass in each of the five samplers deployed in the 

gully located downgradient from the landfill was greater 

than 0.20 mg, including 5.7 mg in sampler 667397, 8.8 mg in 

sampler 667398, and 27 mg in sampler 667422. The largest 

TPH detection was a mass of 85 mg in sampler 662571, which 

is located downgradient from the landfill within 250 ft of the 

wetland. The TPH detections along Gibson Road in samplers 

667412 to 667419 on the northwestern side of the landfill had 

TPH masses less than 1 mg.

TPH was detected from 6.6 to 13 mg in three samplers 

deployed along the southwestern side of the landfill (fig 6; 

table 2). TPH also was detected from 0.49 to 1.7 mg in samplers deployed along a dirt road in the field adjacent to the 

southwestern side of the landfill.

Diesel was detected in 28 of the 56 samplers, including 

detections along all four sides of the landfill, downgradient 

from the landfill toward the wetland, in the gully, and along 

the dirt road in the field southwest of the landfill (fig. 7; table 

2). All three diesel compounds—undecane, tridecane, and 

pentadecane—were detected, but undecane was the most 

common diesel compound with 23 detections (table 2). The 

diesel detections also included 17 detections of tridecane and 

8 detections of pentadecane, but 18 of these detections were 

reported as below detection level. All three diesel compounds 

have MDLs of 0.01 mg; therefore, values for the combined 

mass as diesel were divided into those samplers that had less 

than 0.10 mg (one order of magnitude greater than the MDL) 

and into those samplers equal to or greater than 0.10 mg in 

figure 7. Only five detections, however, exceeded a combined 

diesel mass of 0.10 mg, including 0.12, 0.15 (estimated), and 

0.24 mg along the southwestern side of the landfill from samplers 667409 to 667411, and 0.27 mg (estimated) in samplers 

662571, and 0.11 mg in samplers 667394 southeast of the landfill near the wetland. All other diesel detections were equal to 

or less than an estimated mass of 0.06 mg.

BTEX was detected in only five samplers (fig. 8; table 2). 

Detections of 0.03, 0.05 and 0.06 mg were located next to the 

wetland in sampler 662565 and along the northwestern and 

southwestern sides of the landfill in samplers 667416 and 

667411, respectively. The other two detections were greater, 

including 0.65 mg in sampler 662571 near the wetland and 

0.85 mg on the southwestern side of the landfill in sampler 

667410. Toluene was the only BTEX compound detected in 

all five samplers. The only other gasoline-related compound 

detected in the soil-gas assessment was octane which had a 

mass of 0.07 mg in sampler 667410 and a mass reported as 

below detection level in sampler 667405.

Naphthalene was detected in only four samplers (fig. 9; 

table 2). Two detections of 0.01 mg in sampler 667397 and 

0.02 mg in sampler 667398 were in the gully southeast of 

the landfill. The other two detections of 0.02 mg in sampler 

667409 and a mass reported as below detection level in sampler 667411 were along the southwestern side of the landfill.
10 Soil-gas and groundwater contamination at the Gibson Road landfill, Fort Gordon, Georgia, 2011

Base from U.S. Army 

Albers equal-area conic projection 

Standard parallels 29 ̊20’N and 45 ̊30’N 

Central meridian -96 ̊00’00”

Wetland

0 500 1,000 FEET

0 100 200 300 METERS

GIBSON ROAD

Gibson Road 

Landfill

Gibson Road 

Landfill

Wetland

DIRT ROAD

ACCESS ROAD

667395

667396

662577

667399

667418

667417

667416

667420

667421

667414

667402

667401

667420

667403

667404

667405

667406

667407

667408

667409

667410

667411

667412

667424

667425

667426

667427

667423 667405

667397

667398

667422

667399

667393

667394

667395

667396

662573

662559

662560

662561

662565

662566

662568

662569

662571

662572

667394

662578

667408

667393

662577

662576

662575

662574

667400

662573

662559

662560

662561

662576

662575

662574

667400

667433

667434

667441

667435

667438

667436

667437

667439

667418

667412

667440

Soil-gas sampler location and number – In 

 yellow, orange, and red.

Total petroleum hydrocarbons mass 

 in soil gas in micrograms

 Less than 0.20 

 0.20 to less than 2.0 

 2.0 to less than 20 

 20 or greater

Groundwater sampler location and 

 number – In white

Total petroleum hydrocarbons concentration

 in groundwater in micrograms per liter 

 Less than 100 

 100 or greater

EXPLANATION

667427

667439

N

82°14’40” 82°14’30” 82°14’20”

82°14’40” 82°14’30” 82°14’20”

32°22’10”

32°22’

32°21’50”

32°22’10”

32°22’

32°21’50”

Figure 6. Locations and identification numbers for passive samplers deployed in the soil and the monitoring wells, 

and ranges of mass in the soil gas and concentration in groundwater for total petroleum hydrocarbons (TPH) at the 

Gibson Road landfill, Fort Gordon, Georgia, July 25–29, July 26–29, July 29–August 3, and August 8, 2011. Method 

detection level is 0.02 microgram.
Results 11

Wetland

GIBSON ROAD

Gibson Road 

Landfill

Gibson Road 

Landfill

Wetland

dirt road

ACCESS ROAD

667418

667416 667421

667414

667401

667404

667407

667409

667410

667411

667424

667425

667426

667427

667397

667398

667393

667394

662573

662560

662565

662566

662568

662569

662571

662572

667394

667393

662576

662573

662560

667433

667434

667441

667435

667438

667439

667418

667419

667440

Soil-gas sampler location and number – In 

 yellow, orange, and red.

Diesel mass in soil gas in micrograms

 No detection

 Less than 0.10 

 0.10 to less than 1.0 

Groundwater sampler location and 

 number – In white

Diesel detections in groundwater 

 No detection 

 Diesel detection

EXPLANATION

667427

667439

82°14’40” 82°14’30” 82°14’20”

82°14’40” 82°14’30” 82°14’20”

32°22’10”

32°22’

32°21’50”

32°22’10”

32°22’

32°21’50”

Base from U.S. Army 

Albers equal-area conic projection 

Standard parallels 29 ̊20’N and 45 ̊30’N 

Central meridian -96 ̊00’00”

0 500 1,000 FEET

0 100 200 300 METERS

N

Figure 7. Locations and identification numbers for passive samplers deployed in the soil and the monitoring wells, and 

ranges of combined undecane, tridecane, and pentadecane (C11, C13, and C15) as diesel mass in soil gas, and as diesel 

concentration in groundwater at the Gibson Road landfill, Fort Gordon, Georgia, July 25–29, July 26–29, July 29–August 3, 

and August 8, 2011. Method detection level is 0.02 microgram.
12 Soil-gas and groundwater contamination at the Gibson Road landfill, Fort Gordon, Georgia, 2011

Wetland

GIBSON ROAD

Gibson Road 

Landfill

Gibson Road 

Landfill

Wetland

DIRT ROAD

ACCESS ROAD

667416

667410

667411

662565

662571

667437

667434

667440

Soil-gas sampler location and number – In 

 yellow, orange, and red.

Combined mass of benzene, toluene, ethylbenzene, 

and xylenes (BTEX) in soil gas in micrograms

 No detection

 Less than 0.10 

 0.10 to less than 1.0 

Groundwater sampler location and 

 number – In white

BTEX detections in groundwater 

 No detection 

 BTEX detection

EXPLANATION

667411

667439

Base from U.S. Army 

Albers equal-area conic projection 

Standard parallels 29 ̊20’N and 45 ̊30’N 

Central meridian -96 ̊00’00”

0 500 1,000 FEET

0 100 200 300 METERS

82°14’40” 82°14’30” 82°14’20”

82°14’40” 82°14’30” 82°14’20”

32°22’10”

32°22’

32°21’50”

32°22’10”

32°22’

32°21’50”

N

Figure 8. Locations and identification numbers for passive samplers deployed in the soil and monitoring wells, 

and ranges for combined benzene, toluene, ethylbenzene, and xylene as BTEX mass in the soil gas, and as BTEX 

concentration in groundwater at the Gibson Road landfill, Fort Gordon, Georgia, July 28–29, July 29–August 3, and 

August 8, 2011.
Results 13

Base from U.S. Army 

Albers equal-area conic projection 

Standard parallels 29 ̊20’N and 45 ̊30’N 

Central meridian -96 ̊00’00”

Wetland

0 500 1,000 FEET

0 100 200 300 METERS

ACCESS ROAD

667397

667411

667437

667433

667439

667402

667438

667393

662575

667436

667434

667435 662573

662574

667440

667441

667409

667398 

(naphthalene 

and chloroform) 

Soil-gas sampler location and number – In 

 yellow, orange, red, and blue.

Soil-gas mass in micrograms

 No detection

 Napthalene less than 0.03 

 Chloroform less than 0.10 

 Perchloroethene equal to 0.04

Groundwater sampler location and 

 number – In white

Chlorinated compounds detected in groundwater 

 No detection 

 Detection of at least one chlorinated compound

EXPLANATION

667393

667439

82°14’40” 82°14’30” 82°14’20”

82°14’40” 82°14’30” 82°14’20”

32°22’10”

32°22’

32°21’50”

32°22’10”

32°22’

32°21’50”

N

GIBSON ROAD

Gibson Road 

Landfill

Gibson Road 

Landfill

Wetland

DIRT ROAD

Figure 9. Locations and identification numbers for passive samplers deployed in the soil and the monitoring wells, 

and ranges for naphthalene, chloroform and perchloroethene as masses in the soil gas, and concentrations of 

chlorinated compounds in groundwater at the Gibson Road landfill, Fort Gordon, Georgia, July 28–29, July 29–August 3, 

and August 8, 2011.
14 Soil-gas and groundwater contamination at the Gibson Road landfill, Fort Gordon, Georgia, 2011

Six samplers had detections of chlorinated compounds 

and all six were located southeast (downgradient) of the 

landfill (fig. 9; table 2). Perchloroethene (PCE) was detected 

at 0.04 mg in sampler 667402 at the eastern corner of the 

landfill (table 2). The other chlorinated compound detected in 

the study area was chloroform. All five chloroform detections 

ranged from 0.05 to 0.08 mg. Three samplers (662573, 662574, 

and 662575) had detections of chloroform near the wetland 

and were downgradient from the PCE detection in sampler 

667402. Chloroform also was detected in sampler 667398 with 

a naphthalene detection in the gully and in sampler 667393 to 

the southeast of the landfill.

Groundwater Assessment

Passive samplers in the groundwater assessment were 

deployed and recovered on August 8, 2011, in nine monitoring 

wells along the southwestern, southeastern, and northeastern 

sides from the landfill and downgradient from the eastern 

corner of the landfill (fig. 2). TPH was detected in all samplers 

in the groundwater assessment at concentrations exceeding the 

MDL of 8.3 mg/L (table 3). Six of the nine TPH concentrations 

were greater than 100 mg/L, including concentrations in samplers 667434, 667438, 667439, and 667440 along the southeastern side of the landfill, sampler 667433 on the northeastern 

side of the landfill, and sampler 667435 downgradient from 

the eastern corner of the landfill (fig. 6). The TPH concentrations less than 100 mg/L were in sampler 667441 on the southwestern side of the landfill and downgradient from the landfill 

in samplers 667436 and 667437 near the wetland. Soil-gas 

sampling sites located next to seven of the nine groundwater 

TPH detections had TPH mass greater than 0.20 mg.

Samplers were deployed in four wells roughly aligned 

between the eastern corner of the landfill and the wetland 

(fig. 6). The TPH concentrations declined from a concentration 

of 320 mg/L in upgradient sampler 667434 near the landfill to 

concentrations of 120 mg/L in sampler 667435, 56.20 mg/L in 

sampler 667436, and finally to a concentration of 18 mg/L in 

downgradient sampler 667437 nearest the wetland. TPH in the 

soil-gas samplers ranged from 0.18 to 0.88 mg/L in the area of 

these four monitoring wells with no recognizable pattern of 

downgradient decline in mass.

Five of the samplers had detections of one or more 

diesel compounds but the individual diesel compounds were 

reported as having concentrations below the MDL or were 

nondetectable (table 3). The combined diesel concentration 

for each of these five samplers was 0.00 mg/L. Diesel was 

detected in sampler 667433 on the northeastern side of the 

landfill, samplers 667434 and 667435 near the eastern corner 

of the landfill, sampler 667439 on the southeastern side of 

the landfill, and sampler 667441 on the southwestern side 

of the landfill (fig. 7). The diesel detections located on the 

northeastern and southwestern sides of the landfill were the 

only two groundwater detections associated with detectable 

diesel mass in adjacent samplers in the soil-gas assessment.

Benzene was detected in three samplers and was the only 

BTEX compound detected in the groundwater assessment 

(table 3). The concentrations of benzene and, therefore, BTEX 

were 6.1 mg/L in sampler 667434 near the eastern corner of the 

landfill, 27 mg/L in sampler 667437 at a downgradient location near the wetland, and 37 mg/L in sampler 667440 at the 

southern corner of the landfill (fig. 8). These three concentrations exceed the National Primary Drinking Water Standard of 

5.0 mg/L set for benzene by the USEPA (U.S. Environmental 

Protection Agency, 2009). Benzene and other BTEX compounds were not detected at any of the samplers in the soil-gas 

assessment deployed at the locations of the three groundwater 

samplers with BTEX.

All of the detections of nonfuel-related compounds in the 

groundwater assessment were in the four wells that are aligned 

between the eastern corner of the landfill and the wetland 

(fig. 9; table 3). Sampler 667434 deployed in the well nearest the eastern corner of the landfill is closest to the landfill, 

relative to the other three wells, and had the greatest number 

of detected compounds. Sampler 667434 had the only detections of the two trimethylbenzene compounds, naphthalene, 

2-methyl naphthalene, and 1,4-dichlorobenzene (table 3). 

Chlorinated compounds were detected in samplers deployed in 

these four wells, but the two upgradient samplers (667434 and 

667435) had the greatest number of chlorinated compounds 

with five compounds each, compared to four compounds in 

sampler 667436 and one compound in sampler 667437. The 

chlorinated compound with the highest concentration in each 

of the four samplers was 1,1-dichloroethane which ranged in 

concentration from 1,300 mg/L in sampler 667435 to 42 mg/L 

in downgradient sampler 667437. Other chlorinated compounds detected in the groundwater assessment included TCE 

and PCE in samplers 667434, 667435, and 667436; and cis1,2-dichloroethene in samplers 667434 and 667435. Samplers 

667435 and 667436 had the only detections of 1,1,1-trichloroethane and chloroform, respectively.

The only detection of a chlorinated compound in a soilgas sampler paired with a groundwater sampler was PCE in 

soil-gas sampler 667402 near the eastern corner of the landfill 

(fig. 9). Chloroform was not detected in any of the seven 

samplers in the soil-gas assessment paired with seven samplers in the groundwater assessment. Likewise, none of the 

naphthalene detections in the soil-gas assessment were located 

next to the naphthalene detection in sampler 667434 of the 

groundwater assessment.
Summary 15

Summary

Soil-gas and groundwater assessments were conducted 

at the Gibson Road landfill in 2011 to provide screening-level 

environmental contamination data to supplement the data 

collected during previous environmental studies at the landfill. 

These assessments were completed in cooperation with the 

U.S. Department of the Army Environmental and Natural 

Resources Management Office of the U.S. Army Signal Center 

and Fort Gordon, Georgia.

A total of 56 passive samplers were deployed for the soilgas assessment in the Gibson Road landfill study area. The 

survey mostly identified detections of total petroleum hydrocarbons (TPH) and diesel-range compounds, but also identified the presence of toluene, perchloroethene, chloroform, and 

naphthalene in a few samples. TPH mass exceeded the method 

detection level of 0.02 microgram in all 56 samplers. There 

were 13 TPH detections with masses greater than 2.0 micrograms that were in samplers located along the northeastern 

and southwestern sides of the landfill and southeast (downgradient) of the landfill toward the wetland. Detections in all 

five samplers deployed in the gully located downgradient from 

landfill had TPH masses greater than 0.20 microgram. TPH 

exceeded a mass of 20 micrograms in three samplers located 

between the landfill and the wetland. The largest TPH detection had a mass of 85 micrograms and was in sampler 662571, 

which is located downgradient from the landfill and within 

250 feet of the wetland. TPH was detected in three samplers 

deployed along the southwestern side of the landfill and had 

masses that ranged from 6.6 to 13 micrograms. TPH also was 

detected in samplers deployed farther to the southwest of 

the landfill along a dirt road in the adjacent field, which had 

masses ranging from 0.49 to 1.7 micrograms.

Diesel was detected in 28 of the 56 samplers in the 

soil-gas assessment, including detections along all four sides 

of the landfill, downgradient from the landfill toward the 

wetland, in the gully, and in the field to the southwest of the 

landfill. All three diesel compounds—undecane, tridecane, 

and pentadecane—were detected, but undecane was the most 

common diesel compound with 23 detections. Only five 

detections, however, exceeded a combined diesel mass of 

0.10 microgram, including masses of 0.12, 0.15 (estimated), 

and 0.24 microgram along the southwestern side of the 

landfill, and 0.27 (estimated) and 0.11 microgram in samplers 

southeast of the landfill near the wetland.

Toluene was detected in only five samplers in the soil-gas 

assessment. The detections with the largest masses were a 

sampler near the wetland with a mass of 0.65 microgram and 

a sampler on the southwestern side of the landfill with a mass 

of 0.85 microgram. Toluene was the only BTEX compound 

detected in all five samplers. The only other gasoline-related 

compound detected in the soil-gas assessment was octane 

with a mass of 0.07 microgram in sampler 667410 and a mass 

reported as below detction level in sampler 667405. Naphthalene, detected in two samplers in the gully and two samplers 

along the southwestern side of the landfill, had masses less 

than or equal to 0.02 microgram. Six samplers had detections 

of chlorinated compounds and were located southeast (downgradient) of the landfill. The only detection of perchloroethene 

was in sampler 667402 at the eastern corner of the landfill, 

which had a mass of 0.04 microgram. Five samplers had 

chloroform detections, which had masses ranging from 0.05 to 

0.08 microgram. 

Passive samplers in the groundwater assessment were 

deployed and recovered on August 8, 2011, in nine monitoring 

wells along the southwestern, southeastern, and northeastern 

sides of the landfill and downgradient from the eastern corner 

of the landfill. TPH was detected in all samplers and had concentrations greater than 100 micrograms per liter in six of the 

nine samplers, including samplers along the southeastern and 

northeastern sides of the landfill, and a sampler just downgradient from the eastern corner of the landfill. Soil-gas sampling sites are located next to seven of the nine groundwater 

TPH detections and had TPH masses greater than 0.20 microgram. In four wells aligned between the eastern corner of the 

landfill and the wetland, TPH concentrations declined from 

320 micrograms per liter in an upgradient sampler near the 

landfill to 18 micrograms per liter in a downgradient sampler 

nearest the wetland.

Five of the groundwater samplers had detections of one 

or more diesel compounds, but the individual diesel compounds were reported as having a concentration below the 

MDL or as a nondetection. Benzene was detected in three 

groundwater samplers and was the only BTEX compound 

detected in the groundwater assessment. The concentrations of benzene were 6.1 micrograms per liter in sampler 

667434 at the upgradient location near the eastern corner of 

the landfill, 27 micrograms per liter in sampler 667437 at the 

downgradient location near the wetland, and 37 micrograms 

per liter in sampler 667440 at the southern corner of the 

landfill.

All of the detections of nonfuel-related compounds in the 

groundwater assessment were in the four wells that are aligned 

between the eastern corner of the landfill and the wetland. 

Sampler 667434 deployed in the well nearest the eastern 

corner of the landfill had the greatest diversity of detected 

compounds and had the only detections of the two trimethylbenzene compounds, naphthalene, 2-methyl naphthalene, and 

1,4-dichlorobenzene in the groundwater assessment. The two 

upgradient samplers had the greatest diversity of chlorinated 

compounds with five compounds each, compared to four 

compounds in sampler 667436 and one compound in sampler 667437. Concentrations of 1,1-dichloroethane were the 

highest of all detected organic compounds and ranged from 

1,300 micrograms per liter in sampler 667435 to 42 micrograms per liter in downgradient sampler 667437. Other chlorinated compounds detected in the groundwater assessment 

included trichloroethene, perchloroethene, cis-1,2-dichloroethene, 1,1,1-trichloroethane and chloroform.
16 Soil-gas and groundwater contamination at the Gibson Road landfill, Fort Gordon, Georgia, 2011

References Cited

Atkins, J.B., Journey, C.A., and Clarke, J.S., 1996, Estimation of ground-water discharge to streams in the central 

Savannah River basin of Georgia and South Carolina: 

U.S. Geological Survey Water-Resources Investigations 

Report 96-4179, 36 p.

American Society for Testing and Materials, 2006, Standard 

guide for soil gas monitoring in the vadose zone: West 

Conshohocken, Pa., ASTM D5314-92, 36 p.

Faye, R.E., and Mayer, H.C., 1990, Ground-water and 

stream-aquifer relations in the northern Coastal Plain of 

Georgia and adjacent parts of Alabama and South Carolina: 

U.S. Geological Survey Water-Resources Investigations 

Report 88-4143, 83 p.

Gregory, M.B., Stamey, T.C., and Wellborn, J.B., 2001, 

Ecological characterization of streams, and fish-tissue 

analysis for mercury and lead at selected locations, Fort 

Gordon, Georgia, June 1999 to May 2000: U.S. Geological 

Survey Open-File Report 01-203, 14 p.

Guimaraes, W.B., Falls, W.F., Caldwell, A.W., Ratliff, 

W.H., Wellborn, J.B., and Landmeyer, J.E., 2011, Assessment of groundwater, soil-gas, and soil contamination 

at the Vietnam Armor Training Facility, Fort Gordon, 

Georgia, 2009-2010: U.S. Geological Survey Open-File 

Report 2011-1200, 40 p.

Hetrick, J.H., 1992, A geologic atlas of the Wrens-Augusta 

area: Georgia Geologic Survey Geologic Atlas no. 8, 2 pls.

International Organization for Standardization, 1990, ISO 

Guide 25. General requirements for the competence of 

calibration and testing laboratories (3d ed.): New York, 

American National Standards Institute.

Priest, Sherlyn, and McSwain, K.B., 2002, Hydrogeology 

and water quality of the Upper Three Runs aquifer in the 

vicinity of the Gibson Road Landfill, Fort Gordon, Georgia, 

June–November 1999: U.S. Geological Survey WaterResources Investigations Report 02-4153, 22 p.

U.S. Environmental Protection Agency, 1998, Environmental 

Technology Verification Report Passive Soil Gas Sampler: EPA/600/R-98/095, accessed September 1, 2010, at 

http://www.epa.gov/nrmrl/std/etv/pubs/01_vr_gore.pdf.

U.S. Environmental Protection Agency, 2000, Environmental 

Technology Verification Report Groundwater Sampling 

Technologies: EPA/600/R-00/091, accessed September 1, 

2010 at http://www.epa.gov/nrmrl/std/etv/pubs/

01_vr_gore.pdf.

U.S. Environmental Protection Agency, 2006, The method of 

evaluating solid waste–Physical chemical methods (3d ed.), 

final update IV of SW-846, accessed March 22, 2010, at 

http://www.epa.gov/fedrgstr/EPA-WASTE/2008/January/

Day-03/f25575.htm.

U.S. Environmental Protection Agency, 2009, National 

Primary Drinking Water Regulations: EPA 816-F-09-004, 

6 p., accessed April 30, 2012, at http://www.epa.gov/ogwdw/

consumer/pdf/mcl.pdf.

Williams, L.J., 2007, Hydrogeology and potentiometric 

surface of the Dublin and Midville aquifer systems in 

Richmond County, Georgia, January 2007: U.S. Geological 

Survey Scientific Investigations Map 2982, 1 sheet.

W.L. Gore & Associates, Inc., 2004, GORETM surveys for site 

assessment & monitoring, accessed February 24, 2011, at 

http://www.gore.com/MungoBlobs/239/659/

surveys_environmental_brochure.pdf.
Tables 1–3 17

Tables 1–3

_____________________________________________________________________
18 Soil-gas and groundwater contamination at the Gibson Road landfill, Fort Gordon, Georgia, 2011

Gore 

identification 

number

Use of 

sampler

Latitude, 

decimal degrees

Longitude, 

decimal degrees

Sampling 

period

Date 

analyzed 

662559 Soil Gas 33.367667 82.239194 7/25 – 7/29 8/26

662560 Soil Gas 33.367167 82.240056 7/25 – 7/29 8/25

662561 Soil Gas 33.366417 82.240222 7/25 – 7/29 8/26

662562 Soil Gas 33.366000 82.240056 7/25 – 7/29 8/26

662563 Soil Gas 33.365333 82.240333 7/25 – 7/29 8/26

662564 Soil Gas 33.364139 82.240306 7/25 – 7/29 8/26

662565 Soil Gas 33.362917 82.239667 7/25 – 7/29 8/26

662566 Soil Gas 33.362111 82.239417 7/25 – 7/29 8/26

662567 Soil Gas 33.363806 82.241056 7/25 – 7/29 8/26

662568 Soil Gas 33.362861 82.241222 7/25 – 7/29 8/25

662569 Soil Gas 33.363528 82.242111 7/25 – 7/29 8/25

662570 Soil Gas 33.364361 82.241361 7/25 – 7/29 8/26

662571 Soil Gas 33.365194 82.240917 7/25 – 7/29 8/29

662572 Soil Gas 33.365889 82.240611 7/25 – 7/29 8/25

662573 Soil Gas 33.368000 82.239583 7/25 – 7/29 8/25

662574 Soil Gas 33.367444 82.240250 7/25 – 7/29 8/26

662575 Soil Gas 33.366944 82.240694 7/25 – 7/29 8/25

662576 Soil Gas 33.366250 82.241333 7/25 – 7/29 8/26

662577 Soil Gas 33.365611 82.241750 7/25 – 7/29 8/25

662578 Soil Gas 33.364806 82.242139 7/25 – 7/29 8/26

662579 Soil Gas 33.363833 82.242806 7/25 – 7/29 8/26

667393 Soil Gas 33.364917 82.243194 7/25 – 7/29 8/27

667394 Soil Gas 33.365472 82.241861 7/25 – 7/29 8/26

667395 Soil Gas 33.365472 82.242861 7/25 – 7/29 8/26

667396 Soil Gas 33.366111 82.242444 7/25 – 7/29 8/27

667397 Soil Gas 33.367306 82.242083 7/25 – 7/29 8/26

667398 Soil Gas 33.367222 82.242028 7/25 – 7/29 8/26

667399 Soil Gas 33.367750 82.240972 7/25 – 7/29 8/29

667400 Soil Gas 33.367778 82.239861 7/25 – 7/29 8/27

667401 Soil Gas 33.369250 82.240361 7/25 – 7/29 8/26

667402 Soil Gas 33.368806 82.241056 7/25 – 7/29 8/26

667403 Soil Gas 33.368167 82.241778 7/25 – 7/29 8/25

667404 Soil Gas 33.367833 82.242139 7/25 – 7/29 8/26

667405 Soil Gas 33.367306 82.242583 7/25 – 7/29 8/26

667406 Soil Gas 33.366694 82.243250 7/25 – 7/29 8/25

667407 Soil Gas 33.366278 82.243528 7/25 – 7/29 8/26

667408 Soil Gas 33.365944 82.244000 7/25 – 7/29 8/26

667409 Soil Gas 33.366556 82.244583 7/25 – 7/29 8/26

Table 1. Gore identification numbers and location information for passive samplers 

deployed and recovered in the soil-gas assessment from July 25–29, July 26–29, and 

July 29–August 3, 2011, and groundwater assessment on August 8, 2011, at the 

Gibson Road landfill study area, Fort Gordon, Georgia. 

[—, no data]
Tables 1–3 19

667410 Soil Gas 33.366972 82.244917 7/25 – 7/29 8/26

667411 Soil Gas 33.367583 82.245389 7/25 – 7/29 8/26

667412 Soil Gas 33.368111 82.245917 7/25 – 7/29 8/25

667413 Soil Gas 33.368306 82.246111 7/25 – 7/29 8/25

667414 Soil Gas 33.369278 82.245222 7/25 – 7/29 8/26

667415 Soil Gas 33.369833 82.244444 7/25 – 7/29 8/25

667416 Soil Gas 33.370278 82.243694 7/25 – 7/29 8/26

667417 Soil Gas 33.370722 82.242972 7/25 – 7/29 8/26

667418 Soil Gas 33.371306 82.242083 7/25 – 7/29 8/26

667419 Soil Gas 33.371611 82.241389 7/25 – 7/29 8/25

667420 Soil Gas 33.370333 82.241389 7/25 – 7/29 8/26

667421 Soil Gas 33.369806 82.241333 7/26 – 7/29 8/26

667422 Soil Gas 33.367306 82.241778 7/26 – 7/29 8/29

667423 Soil Gas 33.367250 82.242278 7/26 – 7/29 8/26

667424 Soil Gas 33.367389 82.246750 7/29 – 8/3 8/27

667425 Soil Gas 33.366000 82.246639 7/29 – 8/3 8/26

667426 Soil Gas 33.365417 82.246111 7/29 – 8/3 8/26

667427 Soil Gas 33.364861 82.245667 7/29 – 8/3 8/26

667428 Trip blank — — — 8/26

667429 Trip blank — — — 8/26

667430 Trip blank — — — 8/26

667431 Trip blank — — — 8/26

667432 Trip blank — — — 8/26

667433 Well water 33.369750 82.241278 8/8 8/27

667434 Well water 33.368750 82.240972 8/8 8/27

667435 Well water 33.368278 82.240694 8/8 8/27

667436 Well water 33.368194 82.240222 8/8 8/27

667437 Well water 33.367806 82.239833 8/8 8/27

667438 Well water 33.368083 82.241778 8/8 8/27

667439 Well water 33.366667 82.243167 8/8 8/27

667440 Well water 33.366000 82.243944 8/8 8/27

667441 Well water 33.350306 82.244861 8/8 8/29

667442 Trip blank — — — 8/27

667443 Trip blank — — — 8/27

 — Method blank — — — 8/25

 — Method blank — — — 8/26

 — Method blank — — — 8/27

 — Method blank — — — 8/29

Gore 

identification 

number

Use of 

sampler

Latitude, 

decimal degrees

Longitude, 

decimal degrees

Sampling 

period

Date 

analyzed 

Table 1. Gore identification numbers and location information for passive samplers 

deployed and recovered in the soil-gas assessment from July 25–29, July 26–29, and 

July 29–August 3, 2011, and groundwater assessment on August 8, 2011, at the 

Gibson Road landfill study area, Fort Gordon, Georgia. —Continued

[—, no data]
20 Soil-gas and groundwater contamination at the Gibson Road landfill, Fort Gordon, Georgia, 2011

Table 2. Masses of volatile and semivolatile organic compounds and polycyclic aromatic hydrocarbons detected in passive 

samplers deployed and recovered during the soil-gas assessment in the Gibson Road landfill study area, Fort Gordon, Georgia, 

July 25–29, July 26–29, and July 29–August 3, 2011.

[Raw data provided by W.L. Gore & Associates, Inc. rounded to two significant figures; MDL, method detection level; μg, micrograms; Sampler 662559, 

example of unique identification number assigned by W.L. Gore & Associates to passive sampler; N/A, not applicable; nd, not detected; E, the reported 

value for a combined mass should be considered estimated if the masses of any of the individual compounds used to calculate the combined mass were 

reported as below detection level; bdl, below detection level; a value of 0.00 (reporting format of W.L. Gore & Associates, Inc.) is reported for a combined 

mass if the individual compounds included in the combined mass were not detected above method detection levels and at least one of the individual 

compounds was reported as below detection level]

MDL

(μg)

Sampler

662559 662560 662561 662562 662563 662564 662565 662566 662567 662568 662569

0.02 0.27 0.73 0.22 0.13 0.09 0.17 1.80 1.50 0.12 0.25 5.60

N/A nd nd nd nd nd nd 0.03 nd nd nd nd

0.01 nd nd nd nd nd nd nd nd nd nd nd

0.01 nd nd nd nd nd nd 0.03 nd nd nd nd

0.02 nd nd nd nd nd nd nd nd nd nd nd

0.02 nd nd nd nd nd nd nd nd nd nd nd

0.01 nd nd nd nd nd nd nd nd nd nd nd

N/A nd 0.02 nd nd nd nd E0.02 E0.05 nd 0.00 0.00

0.01 nd 0.02 nd nd nd nd 0.01 0.05 nd nd nd

0.01 nd nd nd nd nd nd 0.01 bdl nd bdl bdl

0.01 nd nd nd nd nd nd bdl bdl nd nd nd

0.02 nd nd nd nd nd nd nd nd nd nd nd

0.03 nd nd nd nd nd nd nd nd nd nd nd

N/A nd nd nd nd nd nd nd nd nd nd nd

0.01 nd nd nd nd nd nd nd nd nd nd nd

0.02 nd nd nd nd nd nd nd nd nd nd nd

0.01 nd nd nd nd nd nd nd nd nd nd nd

0.01 nd nd nd nd nd nd nd nd nd nd nd

0.01 nd nd nd nd nd nd nd nd nd nd nd

0.03 nd nd nd nd nd nd nd nd nd nd nd

0.01 nd nd nd nd nd nd nd nd nd nd nd

N/A nd nd nd nd nd nd nd nd nd nd nd

0.05 nd nd nd nd nd nd nd nd nd nd nd

0.02 nd nd nd nd nd nd nd nd nd nd nd

0.02 nd nd nd nd nd nd nd nd nd nd nd

0.02 nd nd nd nd nd nd nd nd nd nd nd

0.02 nd nd nd nd nd nd nd nd nd nd nd

0.01 nd nd nd nd nd nd nd nd nd nd nd

0.01 nd nd nd nd nd nd nd nd nd nd nd

0.02 nd nd nd nd nd nd nd nd nd nd nd

0.02 nd nd nd nd nd nd nd nd nd nd nd

0.01 nd nd nd nd nd nd nd nd nd nd nd

0.03 nd nd nd nd nd nd nd nd nd nd nd

N/A nd nd nd nd nd nd nd nd nd nd nd

0.01 nd nd nd nd nd nd nd nd nd nd nd

0.01 nd nd nd nd nd nd nd nd nd nd nd

Organic 

compounds

Total petroleum hydrocarbon (TPH)

 BTEX (gasoline)1

 Benzene

 Toluene

 Ethylbenzene

 meta- and para-Xylene

 ortho-Xylene,

 C11, C13, and C15 (diesel)1

 Undecane

 Tridecane

 Pentadecane

Octane

Methyl tert-butyl ether

Trimethylbenzene1

 1,2,4-Trimethylbenzene

 1,3,5-Trimethylbenzene

1,2-Dichlorobenzene

1,3-Dichlorobenzene

1,4-Dichlorobenzene

Chlorobenzene

Chloroform

cis- and trans-1,2-Dichloroethene1

 trans-1,2-Dichloroethene

 cis-1,2-Dichloroethene

Trichloroethene

Perchloroethene

1,1-Dichloroethane

1,2-Dichloroethane

1,1,1-Trichloroethane

1,1,2-Trichloroethane

1,1,1,2-Tetrachloroethane

1,1,2,2-Tetrachloroethane

Carbon tetrachloride

Naphthalene and 2-Methyl naphthalene1

 Naphthalene

 2-Methyl naphthalene
Tables 1–3 21

Table 2. Masses of volatile and semivolatile organic compounds and polycyclic aromatic hydrocarbons detected in passive 

samplers deployed and recovered during the soil-gas assessment in the Gibson Road landfill study area, Fort Gordon, Georgia, 

July 25–29, July 26–29, and July 29–August 3, 2011. —Continued

[Raw data provided by W.L. Gore & Associates, Inc. rounded to two significant figures; MDL, method detection level; μg, micrograms; Sampler 662559, 

example of unique identification number assigned by W.L. Gore & Associates to passive sampler; N/A, not applicable; nd, not detected; E, the reported 

value for a combined mass should be considered estimated if the masses of any of the individual compounds used to calculate the combined mass were 

reported as below detection level; bdl, below detection level; a value of 0.00 (reporting format of W.L. Gore & Associates, Inc.) is reported for a combined 

mass if the individual compounds included in the combined mass were not detected above method detection levels and at least one of the individual 

compounds was reported as below detection level]

MDL

(μg)

Sampler

662570 662571 662572 662573 662574 662575 662576 662577 662578 662579 667393

0.02 0.07 85.00 3.30 0.88 0.34 0.43 1.3 0.11 1.4 0.14 0.23

N/A nd 0.65 nd nd nd nd nd nd nd nd nd

0.01 nd nd nd nd nd nd nd nd nd nd nd

0.01 nd 0.65 nd nd nd nd nd nd nd nd nd

0.02 nd nd nd nd nd nd nd nd nd nd nd

0.02 nd nd nd nd nd nd nd nd nd nd nd

0.01 nd nd nd nd nd nd nd nd nd nd nd

N/A nd E0.27 0.00 0.00 nd nd 0.00 nd nd nd 0.02

0.01 nd 0.27 bdl nd nd nd nd nd nd nd 0.02

0.01 nd nd bdl nd nd nd nd nd nd nd nd

0.01 nd nd nd bdl nd nd bdl nd nd nd nd

0.02 nd nd nd nd nd nd nd nd nd nd nd

0.03 nd nd nd nd nd nd nd nd nd nd nd

N/A nd nd nd nd nd nd nd nd nd nd nd

0.01 nd nd nd nd nd nd nd nd nd nd nd

0.02 nd nd nd nd nd nd nd nd nd nd nd

0.01 nd nd nd nd nd nd nd nd nd nd nd

0.01 nd nd nd nd nd nd nd nd nd nd nd

0.01 nd nd nd nd nd nd nd nd nd nd nd

0.03 nd nd nd nd nd nd nd nd nd nd nd

0.01 nd nd nd 0.06 0.08 0.07 nd nd nd nd 0.05

N/A nd nd nd nd nd nd nd nd nd nd nd

0.05 nd nd nd nd nd nd nd nd nd nd nd

0.02 nd nd nd nd nd nd nd nd nd nd nd

0.02 nd nd nd nd nd nd nd nd nd nd nd

0.02 nd nd nd nd nd nd nd nd nd nd nd

0.02 nd nd nd nd nd nd nd nd nd nd nd

0.01 nd nd nd nd nd nd nd nd nd nd nd

0.01 nd nd nd nd nd nd nd nd nd nd nd

0.02 nd nd nd nd nd nd nd nd nd nd nd

0.02 nd nd nd nd nd nd nd nd nd nd nd

0.01 nd nd nd nd nd nd nd nd nd nd nd

0.03 nd nd nd nd nd nd nd nd nd nd nd

N/A nd nd nd nd nd nd nd nd nd nd nd

0.01 nd nd nd nd nd nd nd nd nd nd nd

0.01 nd nd nd nd nd nd nd nd nd nd nd

Organic 

compounds

Total petroleum hydrocarbon (TPH)

 BTEX (gasoline)1

 Benzene

 Toluene

 Ethylbenzene

 meta- and para-Xylene

 ortho-Xylene,

 C11, C13, and C15 (diesel)1

 Undecane

 Tridecane

 Pentadecane

Octane

Methyl tert-butyl ether

Trimethylbenzene1

 1,2,4-Trimethylbenzene

 1,3,5-Trimethylbenzene

1,2-Dichlorobenzene

1,3-Dichlorobenzene

1,4-Dichlorobenzene

Chlorobenzene

Chloroform

cis- and trans-1,2-Dichloroethene1

 trans-1,2-Dichloroethene

 cis-1,2-Dichloroethene

Trichloroethene

Perchloroethene

1,1-Dichloroethane

1,2-Dichloroethane

1,1,1-Trichloroethane

1,1,2-Trichloroethane

1,1,1,2-Tetrachloroethane

1,1,2,2-Tetrachloroethane

Carbon tetrachloride

Naphthalene and 2-Methyl naphthalene1

 Naphthalene

 2-Methyl naphthalene
22 Soil-gas and groundwater contamination at the Gibson Road landfill, Fort Gordon, Georgia, 2011

MDL

(μg)

Sampler

667394 667395 667396 667397 667398 667399 667400 667401 667402 667403 667404

0.02 2.8 0.18 0.09 5.7 8.8 28 0.18 1.2 0.62 0.26 2.3

N/A nd nd nd nd nd nd nd nd nd nd nd

0.01 nd nd nd nd nd nd nd nd nd nd nd

0.01 nd nd nd nd nd nd nd nd nd nd nd

0.02 nd nd nd nd nd nd nd nd nd nd nd

0.02 nd nd nd nd nd nd nd nd nd nd nd

0.01 nd nd nd nd nd nd nd nd nd nd nd

N/A 0.11 nd nd E0.03 E0.01 nd nd 0.04 nd nd E0.06

0.01 0.10 nd nd 0.03 0.01 nd nd 0.04 nd nd 0.06

0.01 0.01 nd nd bdl bdl nd nd nd nd nd bdl

0.01 nd nd nd nd nd nd nd nd nd nd nd

0.02 nd nd nd nd nd nd nd nd nd nd nd

0.03 nd nd nd nd nd nd nd nd nd nd nd

N/A nd nd nd nd nd nd nd nd nd nd nd

0.01 nd nd nd nd nd nd nd nd nd nd nd

0.02 nd nd nd nd nd nd nd nd nd nd nd

0.01 nd nd nd nd nd nd nd nd nd nd nd

0.01 nd nd nd nd nd nd nd nd nd nd nd

0.01 nd nd nd nd nd nd nd nd nd nd nd

0.03 nd nd nd nd nd nd nd nd nd nd nd

0.01 nd nd nd nd 0.05 nd nd nd nd nd nd

N/A nd nd nd nd nd nd nd nd nd nd nd

0.05 nd nd nd nd nd nd nd nd nd nd nd

0.02 nd nd nd nd nd nd nd nd nd nd nd

0.02 nd nd nd nd nd nd nd nd nd nd nd

0.02 nd nd nd nd nd nd nd nd 0.04 nd nd

0.02 nd nd nd nd nd nd nd nd nd nd nd

0.01 nd nd nd nd nd nd nd nd nd nd nd

0.01 nd nd nd nd nd nd nd nd nd nd nd

0.02 nd nd nd nd nd nd nd nd nd nd nd

0.02 nd nd nd nd nd nd nd nd nd nd nd

0.01 nd nd nd nd nd nd nd nd nd nd nd

0.03 nd nd nd nd nd nd nd nd nd nd nd

N/A nd nd nd 0.01 0.02 nd nd nd nd nd nd

0.01 nd nd nd 0.01 0.02 nd nd nd nd nd nd

0.01 nd nd nd nd nd nd nd nd nd nd nd

Organic 

compounds

Total petroleum hydrocarbon (TPH)

 BTEX (gasoline)1

 Benzene

 Toluene

 Ethylbenzene

 meta- and para-Xylene

 ortho-Xylene,

 C11, C13, and C15 (diesel)1

 Undecane

 Tridecane

 Pentadecane

Octane

Methyl tert-butyl ether

Trimethylbenzene1

 1,2,4-Trimethylbenzene

 1,3,5-Trimethylbenzene

1,2-Dichlorobenzene

1,3-Dichlorobenzene

1,4-Dichlorobenzene

Chlorobenzene

Chloroform

cis- and trans-1,2-Dichloroethene1

 trans-1,2-Dichloroethene

 cis-1,2-Dichloroethene

Trichloroethene

Perchloroethene

1,1-Dichloroethane

1,2-Dichloroethane

1,1,1-Trichloroethane

1,1,2-Trichloroethane

1,1,1,2-Tetrachloroethane

1,1,2,2-Tetrachloroethane

Carbon tetrachloride

Naphthalene and 2-Methyl naphthalene1

 Naphthalene

 2-Methyl naphthalene

Table 2. Masses of volatile and semivolatile organic compounds and polycyclic aromatic hydrocarbons detected in passive 

samplers deployed and recovered during the soil-gas assessment in the Gibson Road landfill study area, Fort Gordon, Georgia, 

July 25–29, July 26–29, and July 29–August 3, 2011. —Continued

[Raw data provided by W.L. Gore & Associates, Inc. rounded to two significant figures; MDL, method detection level; μg, micrograms; Sampler 662559, 

example of unique identification number assigned by W.L. Gore & Associates to passive sampler; N/A, not applicable; nd, not detected; E, the reported 

value for a combined mass should be considered estimated if the masses of any of the individual compounds used to calculate the combined mass were 

reported as below detection level; bdl, below detection level; a value of 0.00 (reporting format of W.L. Gore & Associates, Inc.) is reported for a combined 

mass if the individual compounds included in the combined mass were not detected above method detection levels and at least one of the individual 

compounds was reported as below detection level]
Tables 1–3 23

Table 2. Masses of volatile and semivolatile organic compounds and polycyclic aromatic hydrocarbons detected in passive 

samplers deployed and recovered during the soil-gas assessment in the Gibson Road landfill study area, Fort Gordon, Georgia, 

July 25–29, July 26–29, and July 29–August 3, 2011. —Continued

[Raw data provided by W.L. Gore & Associates, Inc. rounded to two significant figures; MDL, method detection level; μg, micrograms; Sampler 662559, 

example of unique identification number assigned by W.L. Gore & Associates to passive sampler; N/A, not applicable; nd, not detected; E, the reported 

value for a combined mass should be considered estimated if the masses of any of the individual compounds used to calculate the combined mass were 

reported as below detection level; bdl, below detection level; a value of 0.00 (reporting format of W.L. Gore & Associates, Inc.) is reported for a combined 

mass if the individual compounds included in the combined mass were not detected above method detection levels and at least one of the individual 

compounds was reported as below detection level]

MDL

(μg)

Sampler

667405 667406 667407 667408 667409 667410 667411 667412 667413 667414 667415

0.02 0.82 0.76 1.9 0.23 13 6.6 7.4 0.20 0.11 0.73 0.19

N/A nd nd nd nd nd 0.85 0.06 nd nd nd nd

0.01 nd nd nd nd nd nd nd nd nd nd nd

0.01 nd nd nd nd nd 0.85 0.06 nd nd nd nd

0.02 nd nd nd nd nd nd nd nd nd nd nd

0.02 nd nd nd nd nd nd nd nd nd nd nd

0.01 nd nd nd nd nd nd nd nd nd nd nd

N/A nd nd 0.02 nd 0.12 E0.15 0.24 nd nd E0.02 nd

0.01 nd nd 0.02 nd 0.10 0.15 0.22 nd nd 0.02 nd

0.01 nd nd nd nd 0.02 bdl 0.02 nd nd bdl nd

0.01 nd nd nd nd nd nd nd nd nd bdl nd

0.02 bdl nd nd nd nd 0.07 nd nd nd nd nd

0.03 nd nd nd nd nd nd nd nd nd nd nd

N/A nd nd nd nd nd nd nd nd nd nd nd

0.01 nd nd nd nd nd nd nd nd nd nd nd

0.02 nd nd nd nd nd nd nd nd nd nd nd

0.01 nd nd nd nd nd nd nd nd nd nd nd

0.01 nd nd nd nd nd nd nd nd nd nd nd

0.01 nd nd nd nd nd nd nd nd nd nd nd

0.03 nd nd nd nd nd nd nd nd nd nd nd

0.01 nd nd nd nd nd nd nd nd nd nd nd

N/A nd nd nd nd nd nd nd nd nd nd nd

0.05 nd nd nd nd nd nd nd nd nd nd nd

0.02 nd nd nd nd nd nd nd nd nd nd nd

0.02 nd nd nd nd nd nd nd nd nd nd nd

0.02 nd nd nd nd nd nd nd nd nd nd nd

0.02 nd nd nd nd nd nd nd nd nd nd nd

0.01 nd nd nd nd nd nd nd nd nd nd nd

0.01 nd nd nd nd nd nd nd nd nd nd nd

0.02 nd nd nd nd nd nd nd nd nd nd nd

0.02 nd nd nd nd nd nd nd nd nd nd nd

0.01 nd nd nd nd nd nd nd nd nd nd nd

0.03 nd nd nd nd nd nd nd nd nd nd nd

N/A nd nd nd nd 0.02 nd 0.00 nd nd nd nd

0.01 nd nd nd nd 0.02 nd bdl nd nd nd nd

0.01 nd nd nd nd nd nd nd nd nd nd nd

Organic 

compounds

Total petroleum hydrocarbon (TPH)

 BTEX (gasoline)1

 Benzene

 Toluene

 Ethylbenzene

 meta- and para-Xylene

 ortho-Xylene,

 C11, C13, and C15 (diesel)1

 Undecane

 Tridecane

 Pentadecane

Octane

Methyl tert-butyl ether

Trimethylbenzene1

 1,2,4-Trimethylbenzene

 1,3,5-Trimethylbenzene

1,2-Dichlorobenzene

1,3-Dichlorobenzene

1,4-Dichlorobenzene

Chlorobenzene

Chloroform

cis- and trans-1,2-Dichloroethene1

 trans-1,2-Dichloroethene

 cis-1,2-Dichloroethene

Trichloroethene

Perchloroethene

1,1-Dichloroethane

1,2-Dichloroethane

1,1,1-Trichloroethane

1,1,2-Trichloroethane

1,1,1,2-Tetrachloroethane

1,1,2,2-Tetrachloroethane

Carbon tetrachloride

Naphthalene and 2-Methyl naphthalene1

 Naphthalene

 2-Methyl naphthalene
24 Soil-gas and groundwater contamination at the Gibson Road landfill, Fort Gordon, Georgia, 2011

MDL

(μg)

Sampler

667416 667417 667418 667419 667420 667421 667422 667423 667424 667425 667426

0.02 0.56 0.21 0.20 0.19 0.35 5.0 27.0 0.43 0.89 1.7 0.49

N/A 0.05 nd nd nd nd nd nd nd nd nd nd

0.01 nd nd nd nd nd nd nd nd nd nd nd

0.01 0.05 nd nd nd nd nd nd nd nd nd nd

0.02 nd nd nd nd nd nd nd nd nd nd nd

0.02 nd nd nd nd nd nd nd nd nd nd nd

0.01 nd nd nd nd nd nd nd nd nd nd nd

N/A 0.00 nd 0.02 0.01 nd E0.06 nd nd E0.02 E0.01 0.00

0.01 bdl nd nd 0.01 nd 0.04 nd nd 0.02 bdl bdl

0.01 nd nd 0.02 nd nd bdl nd nd bdl 0.01 nd

0.01 nd nd nd nd nd 0.02 nd nd nd nd bdl

0.02 nd nd nd nd nd nd nd nd nd nd nd

0.03 nd nd nd nd nd nd nd nd nd nd nd

N/A nd nd nd nd nd nd nd nd nd nd nd

0.01 nd nd nd nd nd nd nd nd nd nd nd

0.02 nd nd nd nd nd nd nd nd nd nd nd

0.01 nd nd nd nd nd nd nd nd nd nd nd

0.01 nd nd nd nd nd nd nd nd nd nd nd

0.01 nd nd nd nd nd nd nd nd nd nd nd

0.03 nd nd nd nd nd nd nd nd nd nd nd

0.01 nd nd nd nd nd nd nd nd nd nd nd

N/A nd nd nd nd nd nd nd nd nd nd nd

0.05 nd nd nd nd nd nd nd nd nd nd nd

0.02 nd nd nd nd nd nd nd nd nd nd nd

0.02 nd nd nd nd nd nd nd nd nd nd nd

0.02 nd nd nd nd nd nd nd nd nd nd nd

0.02 nd nd nd nd nd nd nd nd nd nd nd

0.01 nd nd nd nd nd nd nd nd nd nd nd

0.01 nd nd nd nd nd nd nd nd nd nd nd

0.02 nd nd nd nd nd nd nd nd nd nd nd

0.02 nd nd nd nd nd nd nd nd nd nd nd

0.01 nd nd nd nd nd nd nd nd nd nd nd

0.03 nd nd nd nd nd nd nd nd nd nd nd

N/A nd nd nd nd nd nd nd nd nd nd nd

0.01 nd nd nd nd nd nd nd nd nd nd nd

0.01 nd nd nd nd nd nd nd nd nd nd nd

Organic 

compounds

Total petroleum hydrocarbon (TPH)

 BTEX (gasoline)1

 Benzene

 Toluene

 Ethylbenzene

 meta- and para-Xylene

 ortho-Xylene,

 C11, C13, and C15 (diesel)1

 Undecane

 Tridecane

 Pentadecane

Octane

Methyl tert-butyl ether

Trimethylbenzene1

 1,2,4-Trimethylbenzene

 1,3,5-Trimethylbenzene

1,2-Dichlorobenzene

1,3-Dichlorobenzene

1,4-Dichlorobenzene

Chlorobenzene

Chloroform

cis- and trans-1,2-Dichloroethene1

 trans-1,2-Dichloroethene

 cis-1,2-Dichloroethene

Trichloroethene

Perchloroethene

1,1-Dichloroethane

1,2-Dichloroethane

1,1,1-Trichloroethane

1,1,2-Trichloroethane

1,1,1,2-Tetrachloroethane

1,1,2,2-Tetrachloroethane

Carbon tetrachloride

Naphthalene and 2-Methyl naphthalene1

 Naphthalene

 2-Methyl naphthalene

Table 2. Masses of volatile and semivolatile organic compounds and polycyclic aromatic hydrocarbons detected in passive 

samplers deployed and recovered during the soil-gas assessment in the Gibson Road landfill study area, Fort Gordon, Georgia, 

July 25–29, July 26–29, and July 29–August 3, 2011. —Continued

[Raw data provided by W.L. Gore & Associates, Inc. rounded to two significant figures; MDL, method detection level; μg, micrograms; Sampler 662559, 

example of unique identification number assigned by W.L. Gore & Associates to passive sampler; N/A, not applicable; nd, not detected; E, the reported 

value for a combined mass should be considered estimated if the masses of any of the individual compounds used to calculate the combined mass were 

reported as below detection level; bdl, below detection level; a value of 0.00 (reporting format of W.L. Gore & Associates, Inc.) is reported for a combined 

mass if the individual compounds included in the combined mass were not detected above method detection levels and at least one of the individual 

compounds was reported as below detection level]
Tables 1–3 25

MDL

(μg)

Sampler Trip blank Laboratory method blank 667427 667428 TB 667429 TB 667430 TB 667431 TB 667432 TB

0.02 0.61 nd nd nd nd nd nd nd nd

N/A nd nd nd nd nd nd nd nd nd

0.01 nd nd nd nd nd nd nd nd nd

0.01 nd nd nd nd nd nd nd nd nd

0.02 nd nd nd nd nd nd nd nd nd

0.02 nd nd nd nd nd nd nd nd nd

0.01 nd nd nd nd nd nd nd nd nd

N/A E0.02 nd nd nd nd nd nd nd nd

0.01 0.02 nd nd nd nd nd nd nd nd

0.01 nd nd nd nd nd nd nd nd nd

0.01 bdl nd nd nd nd nd nd nd nd

0.02 nd nd nd nd nd nd nd nd nd

0.03 nd nd nd nd nd nd nd nd nd

N/A nd nd nd nd nd nd nd nd nd

0.01 nd nd nd nd nd nd nd nd nd

0.02 nd nd nd nd nd nd nd nd nd

0.01 nd nd nd nd nd nd nd nd nd

0.01 nd nd nd nd nd nd nd nd nd

0.01 nd nd nd nd nd nd nd nd nd

0.03 nd nd nd nd nd nd nd nd nd

0.01 nd nd nd nd nd nd nd nd nd

N/A nd nd nd nd nd nd nd nd nd

0.05 nd nd nd nd nd nd nd nd nd

0.02 nd nd nd nd nd nd nd nd nd

0.02 nd nd nd nd nd nd nd nd nd

0.02 nd nd nd nd nd nd nd nd nd

0.02 nd nd nd nd nd nd nd nd nd

0.01 nd nd nd nd nd nd nd nd nd

0.01 nd nd nd nd nd nd nd nd nd

0.02 nd nd nd nd nd nd nd nd nd

0.02 nd nd nd nd nd nd nd nd nd

0.01 nd nd nd nd nd nd nd nd nd

0.03 nd nd nd nd nd nd nd nd nd

N/A nd nd nd nd nd nd nd nd nd

0.01 nd nd nd nd nd nd nd nd nd

0.01 nd nd nd nd nd nd nd nd nd

Table 2. Masses of volatile and semivolatile organic compounds and polycyclic aromatic hydrocarbons detected in passive 

samplers deployed and recovered during the soil-gas assessment in the Gibson Road landfill study area, Fort Gordon, Georgia, 

July 25–29, July 26–29, and July 29–August 3, 2011. —Continued

[Raw data provided by W.L. Gore & Associates, Inc. rounded to two significant figures; MDL, method detection level; μg, micrograms; Sampler 662559, 

example of unique identification number assigned by W.L. Gore & Associates to passive sampler; N/A, not applicable; nd, not detected; E, the reported 

value for a combined mass should be considered estimated if the masses of any of the individual compounds used to calculate the combined mass were 

reported as below detection level; bdl, below detection level; a value of 0.00 (reporting format of W.L. Gore & Associates, Inc.) is reported for a combined 

mass if the individual compounds included in the combined mass were not detected above method detection levels and at least one of the individual 

compounds was reported as below detection level]

Organic 

compounds

Total petroleum hydrocarbon (TPH)

 BTEX (gasoline)1

 Benzene

 Toluene

 Ethylbenzene

 meta- and para-Xylene

 ortho-Xylene,

 C11, C13, and C15 (diesel)1

 Undecane

 Tridecane

 Pentadecane

Octane

Methyl tert-butyl ether

Trimethylbenzene1

 1,2,4-Trimethylbenzene

 1,3,5-Trimethylbenzene

1,2-Dichlorobenzene

1,3-Dichlorobenzene

1,4-Dichlorobenzene

Chlorobenzene

Chloroform

cis- and trans-1,2-Dichloroethene1

 trans-1,2-Dichloroethene

 cis-1,2-Dichloroethene

Trichloroethene

Perchloroethene

1,1-Dichloroethane

1,2-Dichloroethane

1,1,1-Trichloroethane

1,1,2-Trichloroethane

1,1,1,2-Tetrachloroethane

1,1,2,2-Tetrachloroethane

Carbon tetrachloride

Naphthalene and 2-Methyl naphthalene1

 Naphthalene

 2-Methyl naphthalene

1

 Combined mass of two or more compounds with no method detection level provided by laboratory.
26 Soil-gas and groundwater contamination at the Gibson Road landfill, Fort Gordon, Georgia, 2011

Organic 

compound

 MDL

 (μg/L)

Sampler

667433 667434 667435 667436 667437 667438

Total petroleum hydrocarbon (TPH) 8.3 220 320 110 56 18 330

 BTEX (gasoline)1 N/A nd 6.1 nd nd 27 nd

 Benzene 4.1 nd 6.1 nd nd 27 nd

 Toluene 4.1 nd nd nd nd nd nd

 Ethylbenzene 8.3 nd nd nd nd nd nd

 meta- and para- Xylene 8.3 nd nd nd nd nd nd

 ortho-Xylene, 4.1 nd nd nd nd nd nd

 C11, C13, and C15 (diesel)1 N/A 0.00 0.00 0.00 nd nd nd

 Undecane 4.1 nd bdl nd nd nd nd

 Tridecane 4.1 bdl nd bdl nd nd nd

 Pentadecane 4.1 bdl nd bdl nd nd nd

Octane 8.3 nd nd nd nd nd nd

Methyl tert-butyl ether 25 nd nd nd nd nd nd

Trimethylbenzene1 N/A nd 0.00 nd nd nd nd

 1,2,4-Trimethylbenzene 4.1 nd bdl nd nd nd nd

 1,3,5-Trimethylbenzene 8.2 nd bdl nd nd nd nd

1,2-Dichlorobenzene 4.1 nd nd nd nd nd nd

1,3-Dichlorobenzene 4.1 nd nd nd nd nd nd

1,4-Dichlorobenzene 4.1 nd 4.2 nd nd nd nd

Chlorobenzene 12 nd nd nd nd nd nd

Chloroform 4 nd nd nd 22 nd nd

cis- and trans-1,2-Dichloroethene1 N/A nd 0.00 13 nd nd nd

 trans-1,2-Dichloroethene 24 nd nd nd nd nd nd

 cis-1,2-Dichloroethene 8.5 nd bdl 13 nd nd nd

Trichloroethene 8.3 nd 8.6 49 bdl nd nd

Perchloroethene 8.3 nd 9.8 54 13 nd nd

1,1-Dichloroethane 8.3 nd 140 1,300 220 42 nd

1,2-Dichloroethane 4.1 nd nd nd nd nd nd

1,1,1-Trichloroethane 4.1 nd nd 8.2 nd nd nd

1,1,2-Trichloroethane 8.3 nd nd nd nd nd nd

1,1,1,2-Tetrachloroethane 8.3 nd nd nd nd nd nd

1,1,2,2-Tetrachloroethane 4.1 nd nd nd nd nd nd

Carbon tetrachloride 12 nd nd nd nd nd nd

Naphthalene and 2-Methyl naphthalene1 N/A nd E14 nd nd nd nd

 Naphthalene 4.13 nd 14 nd nd nd nd

 2-Methyl naphthalene 4.13 nd bdl nd nd nd nd

Table 3. Concentrations of volatile and semivolatile organic compounds and polycyclic aromatic hydrocarbons detected 

in passive samplers deployed and recovered in the water column of monitoring wells in Gibson Road landfill study area, 

Fort Gordon, Georgia, August 8, 2011. 

[Data as provided by W.L. Gore & Associates, Inc.; MDL, method detection level; μg/L, micrograms per liter; Sampler 667443, example of 

unique identification number assigned by W.L. Gore & Associates to each soil-gas sampler; N/A, not applicable; nd, not detected]
Tables 1–3 27

Organic compound MDL

 (μg/L)

Sampler Trip blank Method

667439 667440 667441 667442 667443 blank

Total petroleum hydrocarbon (TPH) 8.3 170 320 31 bdl bdl nd

 BTEX (gasoline)1 N/A nd 37 nd nd 4.8 nd

 Benzene 4.1 nd 37 nd nd nd nd

 Toluene 4.1 nd nd nd nd 4.8 nd

 Ethylbenzene 8.3 nd nd nd nd nd nd

 meta- and para- Xylene 8.3 nd nd nd nd nd nd

 ortho-Xylene, 4.1 nd nd nd nd nd nd

 C11, C13, and C15 (diesel)1 N/A 0.00 nd 0.00 nd nd nd

 Undecane 4.1 nd nd nd nd nd nd

 Tridecane 4.1 nd nd nd nd nd nd

 Pentadecane 4.1 bdl nd bdl nd nd nd

Octane 8.3 nd nd nd nd nd nd

Methyl tert-butyl ether 25 nd nd nd nd nd nd

Trimethylbenzene1 N/A nd nd nd nd nd nd

 1,2,4-Trimethylbenzene 4.1 nd nd nd nd nd nd

 1,3,5-Trimethylbenzene 8.2 nd nd nd nd nd nd

1,2-Dichlorobenzene 4.1 nd nd nd nd nd nd

1,3-Dichlorobenzene 4.1 nd nd nd nd nd nd

1,4-Dichlorobenzene 4.1 nd nd nd nd nd nd

Chlorobenzene 12 nd nd nd nd nd nd

Chloroform 4 nd nd nd nd nd nd

cis- and trans-1,2-Dichloroethene1 N/A nd nd nd nd nd nd

 trans-1,2-Dichloroethene 24 nd nd nd nd nd nd

 cis-1,2-Dichloroethene 8.5 nd nd nd nd nd nd

Trichloroethene 8.3 nd nd nd nd nd nd

Perchloroethene 8.3 nd nd nd nd nd nd

1,1-Dichloroethane 8.3 nd nd nd nd nd nd

1,2-Dichloroethane 4.1 nd nd nd nd nd nd

1,1,1-Trichloroethane 4.1 nd nd nd nd nd nd

1,1,2-Trichloroethane 8.3 nd nd nd nd nd nd

1,1,1,2-Tetrachloroethane 8.3 nd nd nd nd nd nd

1,1,2,2-Tetrachloroethane 4.1 nd nd nd nd nd nd

Carbon tetrachloride 12 nd nd nd nd nd nd

Naphthalene and 2-Methyl naphthalene1 N/A nd nd nd nd nd nd

 Naphthalene 4.13 nd nd nd nd nd nd

 2-Methyl naphthalene 4.13 nd nd nd nd nd nd

1

 Combined concentrations of two or more compounds with no method detection level provided by laboratory.

Table 3. Concentrations of volatile and semivolatile organic compounds and polycyclic aromatic hydrocarbons detected 

in passive samplers deployed and recovered in the water column of monitoring wells in Gibson Road landfill study area, 

Fort Gordon, Georgia, August 8, 2011. —Continued

[Data as provided by W.L. Gore & Associates, Inc.; MDL, method detection level; μg/L, micrograms per liter; Sampler 667443, example of 

unique identification number assigned by W.L. Gore & Associates to each soil-gas sampler; N/A, not applicable; nd, not detected]
28 Soil-gas and groundwater contamination at the Gibson Road landfill, Fort Gordon, Georgia, 2011

Prepared by: 

USGS Publishing Network 

Raleigh Publishing Service Center 

3916 Sunset Ridge Road 

Raleigh, NC 27607

For additional information regarding this publication, contact: 

USGS South Carolina Water Science Center 

Stephenson Center, Suite 129 

720 Gracern Road 

Columbia, SC 29210-7651 

Or visit the USGS South Carolina Water Science Center Web site at: 

http://sc.water.usgs.gov

W. F. Falls and others—Assessment of Soil-Gas and Groundwater Contamination, Gibson Road Landfill, Fort Gordon, Georgia, 2011—OFR 2012–1128