Base extracted from U.S. Geological Survey 1:7,500-scale Digital Raster Graphic (DRG), 2004

Universal Transverse Mercator projection, Zone 12

Horizontal coordinate information is referenced to the North American Datum of 1983 (NAD83)

Vertical coordinate information is referenced to the North Americal Vertical Datum of 1988 (NAD88)

Concentration of 1,4-Dioxane in Wells Sampled During 2002–2009 in the Vicinity of the

Tucson International Airport Area Superfund Site, Arizona

By

Fred D Tillman

2010

When this map is printed on an electronic plotter directly from 

digital files, dimensional calibration may vary between X and Y 

directions on the same plotter, and paper may change size due to 

atmospheric conditions; therefore, scale and proportions may 

not be true on plots of this map

For sale by U.S. Geological Survey, Information Services, Box 

25286, Federal Center, Denver, CO 80225, or call 1-888-ASK-USGS

Available at http://pubs.usgs.gov/sim/3113

1 0.125 0.25 0.5 0.75 1 KILOMETER

1 0.125 0.25 0.5 0.75 1 MILE

SCALE 1: 7 500 Data compiled by Fred D Tillman

Digital cartography by Fred D Tillman

Edited by J.L. Zigler; cartography by D.A. Ryan

Manuscript approved for publication January 29, 2010

INTERSTATE 19

INTERSTATE 19

IRVINGTON RD IRVINGTON RD

DREXEL RD

BILBY RD

VALENCIA RD VALENCIA RD

LOS REALES RD

NOGALES HWY

NOGALES HWY

12TH AVE 12TH AVE

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.

FLAGSTAFF

PRESCOTT

PHOENIX

YUMA

TUCSON TUCSON INTERNATIONAL 

AIRPORT AREA 

SUPERFUND SITE

U.S. AIR FORCE CENTER FOR ENGINEERING AND THE ENVIRONMENTRESTORATION PROGRAM MANAGMENT OFFICE

EXPLANATION

.!

!.

!.

!.

Monitoring well

Supply well

Private well

Former supply well

Display All

Select well type to display

only that well type.

02

0

2

4

6

8

10

12

14

16

03 04 05

SAMPLE DATE

1,4-DIOXANE (ppb)

06 07 08 09

PW020 Well Depth

140 (ft)

Opening

unknown

Sample collection date (20xx)

Data source

Depth of well, if known, in 

feet below land surface

USEPA Drinking Water

Advisory Level of 3 ppb

1,4-dioxane 

concentration, in 

parts per billion 

(micrograms per 

liter)

USEPA Region 9 

Preliminary Remediation 

Goal of 6.1 ppb

Well identifier

Depth of well opening, 

if known, in feet below 

land surface

Pima DEQ

USGS

Data Source 

(See References Cited for complete source reference)

Pima DEQ Pima County Department of Environ-

 mental Quality (2009)

Tucson Intl Airport Connestoga-Rovers & Associates

 (2007, 2009)

Tucson Water Malcolm Pirnie, Inc. (2007, 2009)

USGS Tillman (2009)

Introduction

Extensive groundwater contamination resulting from industrial activities led to the listing of the Tucson International Airport Area as a Superfund Site in 1983. 

Early investigations revealed elevated levels of volatile organic compounds (VOCs) including the chlorinated solvents trichloroethylene (TCE) and perchloroethylene (PCE) in wells in the area. Several responsible parties were identified and cleanup activities were begun in the late 1980s using technology designed for 

removal of VOCs. In 2002, the compound 1,4-dioxane was discovered in wells in the Tucson Airport Remediation Project (TARP) area. Since then, 1,4-dioxane 

has been detected throughout the TARP area, in some cases exceeding the U.S. Environmental Protection Agency (USEPA) drinking water advisory level of 3 μg/L 

(U.S. Environmental Protection Agency, 2006).

Purpose and Scope

The purpose of this map is to present 1,4-dioxane temporal data from wells sampled from 2002 through 2009 in the TARP area, which shows trends in well 

concentrations. This map includes data from wells in the commercial and residential community in the TARP area and does not include data from wells in 

suspected or confirmed source areas such as Air Force Plant 44 and Tucson International Airport or from wells within treatment facilities. Data from agency reports 

including the U.S. Geological Survey, Pima County Department of Environmental Quality, Tucson International Airport, and Tucson Water are included on the 

map.

Methods

Data from all wells sampled and analyzed for 1,4-dioxane in the TARP area were compiled from available sources (Appendix A at http://pubs.usgs.gov/sim/3113/). 

These data were plotted on time-series charts, using a value of one-half the reporting limit for all samples reported as “non-detect”. All charts utilize the same scale 

of data points for both the horizonal sample date and the vertical 1,4-dioxane concentration. This permits ease of comparison of concentration levels between wells. 

Basic well construction information of depth of well in feet below land surface and depth of well openings in feet below land surface, if available, is placed in the 

chart header with the local well identifier. Well construction information and well location information were obtained from the U.S. Geological Survey and the 

Arizona Department of Water Resources databases. Horizontal dashed lines on the charts indicate the USEPA Region 9 Preliminary Remediation Goal of 6.1 ppb 

(U.S. Environmental Protection Agency, 2009) and the USEPA Drinking Water Advisory Level of 3 ppb (U.S. Environmental Protection Agency, 2006). Well 

locations are plotted on an aerial photo of the TARP area in a Geographic Information System (GIS) using colored symbols to differentiate between monitoring, 

supply, former supply, and private wells. Charts are placed as closely as possible to well locations on the map, and colored arrows link the chart to the well.

Wells were sampled using collection, handling, and analysis methods approved by each collecting organization (see data sources listed in explanation for information on sample collection and analysis methods). Former supply wells were sampled using disposable polyethylene bailers and were not purged prior to sample 

collection. While a significant mass of dissolved 1,4-dioxane is not likely to volatilize out of water under natural conditions, results from these bailed wells indicate 

only the concentration of 1,4-dioxane in the borehole water at the time of sampling and do not necessarily represent concentrations in the surrounding aquifer.

Acknowledgements

The author wishes to thank Marc Herman of Pima County Department of Environmental Quality, Craig Kafura of Arizona Department of Environmental Quality, 

Fred Brinker of the Tucson International Airport Authority, Catherine Schladweiler of Malcolm Pirnie, Arizona Department of Water Resources, and ConestogaRovers and Associates for providing access to information and data used in this report. In particular, the author would like to thank Stephen Dean, Joe Huerstel, 

Nagieb Mussa, and Michael Dew of the City of Tucson Water Department for their continued assistance in sampling wells in the TARP area.

References Cited

Conestoga-Rovers & Associates, 2007, Groundwater monitoring results for 1,4-dioxane sampling, TIAA superfund site—Airport property, Tucson, Arizona: 

Conestoga-Rovers & Associates, Reference No. 013711-89, 130 p.

Conestoga-Rovers & Associates, 2009, Groundwater monitoring results for 1,4-dioxane sampling, TIAA superfund site—Airport property, Tucson, Arizona: 

Conestoga-Rovers & Associates, Reference No. 013711-281, 12 p.

Malcolm Pirnie, Inc., 2007, Tucson International Airport area Groundwater Remediation Project, semi-annual status report, September 2006 through February 

2007: Malcolm Pirnie, Inc., no. 1830-086, 193 p.

Malcolm Pirnie, Inc., 2009, Tucson International Airport Area Groundwater Remediation Project, semi-annual status report, March 2009 through August 2009: 

Malcolm Pirnie, Inc., no. 1830-086, 202 p.

Pima County Department of Environmental Quality, 2009, South-side private well monitoring program, Tucson International Airport area superfund site, Tucson, 

Arizona: Pima County Department of Environmental Quality, Annual Report, April 2009, 52 p.

Tillman, F.D, 2009, Results of the analyses for 1,4-dioxane of groundwater samples collected in the Tucson Airport Remediation Project area: U.S. Geological 

Survey Open-File Report 2009-1196, 14 p.

U.S. Environmental Protection Agency, 2006, 2006 Edition of the drinking water standards and health advisories: U.S. Environmental Protection Agency, Office of 

Water, EPA 822-R-06-013, 18 p. [http://www.epa.gov/waterscience/criteria/drinking/dwstandards.pdf, last accessed August 17, 2009].

U.S. Environmental Protection Agency, 2009, Regional screening levels (RSL) for chemical contaminants at superfund sites: U.S. Environmental Protection 

Agency RSL Table Update, April 2009, 85 p. [http://www.epa.gov/region09/superfund/prg/pdf/composite_sl_table_bwrun_APRIL2009.pdf, last accessed 

August 17, 2009].

32°10'N

32°09'N

32°08'N

110°59'W 110°58'W 110°57'W

110°59'W 110°58'W 110°57'W

32°10'N

32°09'N

32°08'N

02 0

2

4

6

8

10

12

14

16

03 04 05

SAMPLE DATE

1,4-DIOXANE (ppb)

06 07 08 09

D-7 Well Depth

139 (ft)

Opening

129-139 (ft)

Tucson Intl Airport

02

0

2

4

6

8

10

12

14

16

03 04 05

SAMPLE DATE

1,4-DIOXANE (ppb)

06 07 08 09

S-37 Well Depth

112 (ft)

Opening

101-110 (ft)

Tucson Intl Airport

02

0

2

4

6

8

10

12

14

16

03 04 05

SAMPLE DATE

1,4-DIOXANE (ppb)

06 07 08 09

S-39 Well Depth

131 (ft)

Opening

126-129 (ft)

Tucson Intl Airport

02

0

2

4

6

8

10

12

14

16

03 04 05

SAMPLE DATE

1,4-DIOXANE (ppb)

06 07 08 09

S-26 Well Depth

126 (ft)

Opening

108-123 (ft)

Tucson Intl Airport

02

0

2

4

6

8

10

12

14

16

03 04 05

SAMPLE DATE

1,4-DIOXANE (ppb)

06 07 08 09

EW-4 Well Depth

126 (ft)

Opening

109-119 (ft)

Tucson Intl Airport

EPA 7 Well Depth

393 (ft)

Opening

323-372 (ft)

02

0

2

4

6

8

10

12

14

16

03 04 05

SAMPLE DATE

1,4-DIOXANE (ppb)

06 07 08 09

USGS

02

0

2

4

6

8

10

12

14

16

03 04 05

SAMPLE DATE

1,4-DIOXANE (ppb)

06 07 08 09

EPA 10 Well Depth

235 (ft)

Opening

167-215 (ft)

Tucson Water

USGS

02

0

2

4

6

8

10

12

14

16

03 04 05

SAMPLE DATE

1,4-DIOXANE (ppb)

06 07 08 09

WR-055 B Well Depth

233 (ft)

Opening

213-233 (ft)

Tucson Water

USGS

02 0

2

4

6

8

10

12

14

16

03 04 05

SAMPLE DATE

1,4-DIOXANE (ppb)

06 07 08 09

WR-056 B Well Depth

178 (ft)

Opening

158-178 (ft)

Tucson Water

USGS

02 0

2

4

6

8

10

12

14

16

03 04 05

SAMPLE DATE

1,4-DIOXANE (ppb)

06 07 08 09

WR-056 C Well Depth

130 (ft)

Opening

110-130 (ft)

Tucson Water

USGS

02 0

2

4

6

8

10

12

14

16

03 04 05

SAMPLE DATE

1,4-DIOXANE (ppb)

06 07 08 09

WR-057 A Well Depth

160 (ft)

Opening

130-160 (ft)

Tucson Water

USGS

02

0

2

4

6

8

10

12

14

16

03 04 05

SAMPLE DATE

1,4-DIOXANE (ppb)

06 07 08 09

WR-058 A Well Depth

400 (ft)

Opening

360-400 (ft)

Tucson Water

USGS

02

0

2

4

6

8

10

12

14

16

03 04 05

SAMPLE DATE

1,4-DIOXANE (ppb)

06 07 08 09

WR-058 B Well Depth

144 (ft)

Opening

124-144 (ft)

Tucson Water

USGS

WR-059 A Well Depth

401 (ft)

Opening

361-401 (ft)

02 0

2

4

6

8

10

12

14

16

03 04 05

SAMPLE DATE

1,4-DIOXANE (ppb)

06 07 08 09

USGS

02 0

2

4

6

8

10

12

14

16

03 04 05

SAMPLE DATE

1,4-DIOXANE (ppb)

06 07 08 09

WR-059 B Well Depth

141 (ft)

Opening

121-141 (ft)

Tucson Water

USGS

02 0

2

4

6

8

10

12

14

16

03 04 05

SAMPLE DATE

1,4-DIOXANE (ppb)

06 07 08 09

WR-076 S Well Depth

400 (ft)

Opening

300-400 (ft)

Tucson Water

USGS

02

0

2

4

6

8

10

12

14

16

03 04 05

SAMPLE DATE

1,4-DIOXANE (ppb)

06 07 08 09

WR-077 S Well Depth

130 (ft)

Opening

100-130 (ft)

Tucson Water

USGS

02 0

2

4

6

8

10

12

14

16

03 04 05

SAMPLE DATE

1,4-DIOXANE (ppb)

06 07 08 09

WR-078 S Well Depth

160 (ft)

Opening

110-160 (ft)

Tucson Water

USGS

Tucson Water

USGS

02 0

2

4

6

8

10

12

14

16

03 04 05

SAMPLE DATE

1,4-DIOXANE (ppb)

06 07 08 09

WR-079 S Well Depth

145 (ft)

Opening

95-145 (ft)

02 0

2

4

6

8

10

12

14

16

03 04 05

SAMPLE DATE

1,4-DIOXANE (ppb)

06 07 08 09

WR-081 S Well Depth

175 (ft)

Opening

95-175 (ft)

Tucson Water

USGS

02 0

2

4

6

8

10

12

14

16

03 04 05

SAMPLE DATE

1,4-DIOXANE (ppb)

06 07 08 09

WR-082 S Well Depth

158 (ft)

Opening

108-158 (ft)

Tucson Water

USGS

02 0

2

4

6

8

10

12

14

16

03 04 05

SAMPLE DATE

1,4-DIOXANE (ppb)

06 07 08 09

WR-080 S Well Depth

150 (ft)

Opening

100-150 (ft)

Tucson Water

USGS

02

0

2

4

6

8

10

12

14

16

03 04 05

SAMPLE DATE

1,4-DIOXANE (ppb)

06 07 08 09

WR-084 S Well Depth

160 (ft)

Opening

130-160 (ft)

Tucson Water

USGS

02 0

2

4

6

8

10

12

14

16

03 04 05

SAMPLE DATE

1,4-DIOXANE (ppb)

06 07 08 09

WR-085 S Well Depth

190 (ft)

Opening

110-190 (ft)

Tucson Water

USGS

Tucson Water

USGS

02 0

2

4

6

8

10

12

14

16

03 04 05

SAMPLE DATE

1,4-DIOXANE (ppb)

06 07 08 09

WR-086 S Well Depth

140 (ft)

Opening

100-140 (ft)

02 0

2

4

6

8

10

12

14

16

03 04 05

SAMPLE DATE

1,4-DIOXANE (ppb)

06 07 08 09

WR-241 A Well Depth

402 (ft)

Opening

152-402 (ft)

Tucson Water

USGS

02 0

2

4

6

8

10

12

14

16

03 04 05

SAMPLE DATE

1,4-DIOXANE (ppb)

06 07 08 09

WR-163 A Well Depth

350 (ft)

Opening

300-350 (ft)

Tucson Water

USGS

02 0

2

4

6

8

10

12

14

16

03 04 05

SAMPLE DATE

1,4-DIOXANE (ppb)

06 07 08 09

WR-091 S Well Depth

175 (ft)

Opening

125-175 (ft)

Tucson Water

USGS

02 0

2

4

6

8

10

12

14

16

03 04 05

SAMPLE DATE

1,4-DIOXANE (ppb)

06 07 08 09

WR-087 S Well Depth

240 (ft)

Opening

140-240 (ft)

Tucson Water

USGS

02

0

2

4

6

8

10

12

14

16

03 04 05

SAMPLE DATE

1,4-DIOXANE (ppb)

06 07 08 09

WR-089 S Well Depth

405 (ft)

Opening

300-400 (ft)

Tucson Water

USGS

02 0

2

4

6

8

10

12

14

16

03 04 05

SAMPLE DATE

1,4-DIOXANE (ppb)

06 07 08 09

WR-090 S Well Depth

215 (ft)

Opening

115-215 (ft)

Tucson Water

02 0

2

4

6

8

10

12

14

16

03 04 05

SAMPLE DATE

1,4-DIOXANE (ppb)

06 07 08 09

WR-165 A Well Depth

350 (ft)

Opening

300-350 (ft)

Tucson Water

USGS

02 0

2

4

6

8

10

12

14

16

03 04 05

SAMPLE DATE

1,4-DIOXANE (ppb)

06 07 08 09

WR-236 A Well Depth

250 (ft)

Opening

150-250 (ft)

Tucson Water

USGS

02 0

2

4

6

8

10

12

14

16

03 04 05

SAMPLE DATE

1,4-DIOXANE (ppb)

06 07 08 09

WR-237 A Well Depth

400 (ft)

Opening

150-400 (ft)

Tucson Water

USGS

02 0

2

4

6

8

10

12

14

16

03 04 05

SAMPLE DATE

1,4-DIOXANE (ppb)

06 07 08 09

WR-240 A Well Depth

400 (ft)

Opening

150-400 (ft)

Tucson Water

USGS

02 0

2

4

6

8

10

12

14

16

03 04 05

SAMPLE DATE

1,4-DIOXANE (ppb)

06 07 08 09

WR-239 A Well Depth

400 (ft)

Opening

150-400 (ft)

Tucson Water

USGS

02 0

2

4

6

8

10

12

14

16

03 04 05

SAMPLE DATE

1,4-DIOXANE (ppb)

06 07 08 09

WR-238 A Well Depth

380 (ft)

Opening

150-280 (ft)

Tucson Water

USGS

02 0

2

4

6

8

10

12

14

16

03 04 05

SAMPLE DATE

1,4-DIOXANE (ppb)

06 07 08 09

WR-700 A Well Depth

177 (ft)

Opening

100-170 (ft)

Tucson Water

USGS

PW-020 Well Depth

140 (ft)

Opening

unknown

02 0

2

4

6

8

10

12

14

16

03 04 05

SAMPLE DATE

1,4-DIOXANE (ppb)

06 07 08 09

Pima DEQ

USGS

02

0

2

4

6

8

10

12

14

16

03 04 05

SAMPLE DATE

1,4-DIOXANE (ppb)

06 07 08 09

Pima DEQ

PW-011 Well Depth

223 (ft)

Opening

unknown

02

0

2

4

6

8

10

12

14

16

03 04 05

SAMPLE DATE

1,4-DIOXANE (ppb)

06 07 08 09

PW-003 Well Depth

unknown

Opening

unknown

Pima DEQ

02

0

2

4

6

8

10

12

14

16

03 04 05

SAMPLE DATE

1,4-DIOXANE (ppb)

06 07 08 09

PW-012 Well Depth

212 (ft)

Opening

unknown

Pima DEQ

02

0

2

4

6

8

10

12

14

16

03 04 05

SAMPLE DATE

1,4-DIOXANE (ppb)

06 07 08 09

Pima DEQ

PW-013 Well Depth

unknown

Opening

unknown

02

0

2

4

6

8

10

12

14

16

03 04 05

SAMPLE DATE

1,4-DIOXANE (ppb)

06 07 08 09

PW-014 Well Depth

unknown

Opening

unknown

Pima DEQ 02

0

2

4

6

8

10

12

14

16

03 04 05

SAMPLE DATE

1,4-DIOXANE (ppb)

06 07 08 09

PW-007 Well Depth

150 (ft)

Opening

unknown

Pima DEQ

02 0

2

4

6

8

10

12

14

16

03 04 05

SAMPLE DATE

1,4-DIOXANE (ppb)

06 07 08 09

R-001 A Well Depth

165 (ft)

Opening

110-150 (ft)

Tucson Water

USGS

02 0

2

4

6

8

10

12

14

16

03 04 05

SAMPLE DATE

1,4-DIOXANE (ppb)

06 07 08 09

R-002 A Well Depth

171 (ft)

Opening

110-150 (ft)

Tucson Water

USGS

02 0

2

4

6

8

10

12

14

16

03 04 05

SAMPLE DATE

1,4-DIOXANE (ppb)

06 07 08 09

R-003 A Well Depth

169 (ft)

Opening

120-155 (ft)

USGS Tucson Water

02 0

2

4

6

8

10

12

14

16

03 04 05

SAMPLE DATE

1,4-DIOXANE (ppb)

06 07 08 09

R-004 A Well Depth

175 (ft)

Opening

125-160 (ft)

Tucson Water

USGS

02 0

2

4

6

8

10

12

14

16

03 04 05

SAMPLE DATE

1,4-DIOXANE (ppb)

06 07 08 09

R-006 A Well Depth

419 (ft)

Opening

180-400 (ft)

Tucson Water

USGS

02 0

2

4

6

8

10

12

14

16

03 04 05

SAMPLE DATE

1,4-DIOXANE (ppb)

06 07 08 09

R-007 A Well Depth

424 (ft)

Opening

178-398 (ft)

Tucson Water

USGS

02 0

2

4

6

8

10

12

14

16

03 04 05

SAMPLE DATE

1,4-DIOXANE (ppb)

06 07 08 09

R-008 A Well Depth

426 (ft)

Opening

180-400 (ft)

Tucson Water

USGS

02

0

2

4

6

8

10

12

14

16

03 04 05

SAMPLE DATE

1,4-DIOXANE (ppb)

06 07 08 09

R-009 A Well Depth

425 (ft)

Opening

175-395 (ft)

Tucson Water

USGS

02 0

2

4

6

8

10

12

14

16

03 04 05

SAMPLE DATE

1,4-DIOXANE (ppb)

06 07 08 09

SS-021 A Well Depth

320 (ft)

Opening

120-300 (ft)

Tucson Water

USGS

02 0

2

4

6

8

10

12

14

16

03 04 05

SAMPLE DATE

1,4-DIOXANE (ppb)

06 07 08 09

SS-023 B Well Depth

420 (ft)

Opening

260-400 (ft)

Tucson Water

USGS

02

0

2

4

6

8

10

12

14

16

03 04 05

SAMPLE DATE

1,4-DIOXANE (ppb)

06 07 08 09

R-005 A Well Depth

155 (ft)

Opening

100-140 (ft)

Tucson Water

USGS

02 0

2

4

6

8

10

12

14

16

03 04 05

SAMPLE DATE

1,4-DIOXANE (ppb)

06 07 08 09

B-103 A Well Depth

522 (ft)

Opening

65-150

USGS

C-066 A Well Depth

743 (ft)

Opening

68-743 (ft)

02 0

2

4

6

8

10

12

14

16

03 04 05

SAMPLE DATE

1,4-DIOXANE (ppb)

06 07 08 09

USGS

C-081 A Well Depth

520 (ft)

Opening

79-520 (ft)

02 0

2

4

6

8

10

12

14

16

03 04 05

SAMPLE DATE

1,4-DIOXANE (ppb)

06 07 08 09

USGS

C-077 A Well Depth

150 (ft)

Opening

50-150 (ft)

02 0

2

4

6

8

10

12

14

16

03 04 05

SAMPLE DATE

1,4-DIOXANE (ppb)

06 07 08 09

USGS

C-078 A Well Depth

230 (ft)

Opening

32-230 (ft)

02 0

2

4

6

8

10

12

14

16

03 04 05

SAMPLE DATE

1,4-DIOXANE (ppb)

06 07 08 09

USGS

C-064 A Well Depth

189 (ft)

Opening

75-165 (ft)

02

0

2

4

6

8

10

12

14

16

03 04 05

SAMPLE DATE

1,4-DIOXANE (ppb)

06 07 08 09

USGS

C-064 B Well Depth

900 (ft)

Opening

107-900 (ft)

02

0

2

4

6

8

10

12

14

16

03 04 05

SAMPLE DATE

1,4-DIOXANE (ppb)

06 07 08 09

USGS

02 0

2

4

6

8

10

12

14

16

03 04 05

SAMPLE DATE

1,4-DIOXANE (ppb)

06 07 08 09

PK-010 A Well Depth

250 (ft)

Opening

92-250

USGS