&EPA
United States
Environmental Protection
Agency
Office of Radiation and
Indoor Air
Washington, DC 20460
EPA-402-R-01-002
February 2001
Annual Water Sampling and
Analysis, Calendar Year 2000:
RULISON Test Site Area
RIO BLANCO Test Site Area
FAULTLESS Test Site Area
SHOAL Test Site Area
GASBUGGY Test Site Area
GNOME Test Site Area
-------
Annual Water Sampling and
Analysis, Calendar Year 2000
RULISON Test Site Area
RIO BLANCO Test Site Area
FAULTLESS Test Site Area
SHOAL Test Site Area
GASBUGGY Test Site Area
GNOME Test Site Area
by
Max G. Davis
Prepared for the U.S. Department of Energy
under Interagency Agreement
DE-AI08-96NV11969
".
~~
"'.....,.
4!,
RADIATION AND INDOOR ENVIRONMENTS NATIONAL LABORATORY
OFFICE OF RADIATION AND INDOOR AIR
U.S. ENVIRONMENTAL PROTECTION AGENCY
P.O. BOX 98517
LAS VEGAS, NV 89193-8517
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NOTICE
The information in this document has been funded wholly or in part by the United States
Environmental Protection Agency (EP A) through Interagency Agreement (lAG) DE-AI08-96 NV
11969 from the United States Department of Energy (DOE). This document has been subjected
to the Agency's peer and administrative review, and it has been approved for publication as an
EP A document. Mention of trade names or commercial products does not constitute
endorsement or recommendation for use.
11
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ABSTRACT
The U. S. Environmental Protection Agency, Radiation and Indoor Environments National
Laboratory in Las Vegas, Nevada (R&IE), operates the radiological surveillance program
surrounding the Nevada Test Site (NTS) and, in addition, monitors former nuclear test areas in
Alaska, Colorado, Mississippi, Nevada, and New Mexico, each year under the Long Term
Hydrological Monitoring Program (L THMP). The L THMP is designed to detect residual man-
made radionuclides in surface and ground water resulting from underground nuclear test
activities. This report describes the sampling and analysis of water samples collected from six
former nuclear test sites in three western states during 2000; Projects Rulison and Rio Blanco in
Colorado; Projects Shoal and Faultless in Nevada; and Projects Gasbuggy and Gnome in New
Mexico. Monitoring results for Alaska and Mississippi are reported separately.
Radiological results for 2000 are consistent with results from previous years and no increase was
seen in either tritium concentrations or gamma-ray emitting radionuclides at any site. Tritium
levels at the sites are generally decreasing or stable and are well below the National Primary
Drinking Water Standard for tritium of20,000 pCi/L, with the exception of samples from several
deep wells adjacent to the nuclear cavity at the Gnome site. As in previous years, the highest
tritium value recorded for any sample, 4.5 x 107 pCi/L, was from one of these wells, Well DD-l
(project Gnome).
11l
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This page left blank intentionally
IV
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CONTENTS
Page
Notice. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . " 11
Abstract. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . iii
Figures and Tables. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . '.' . . VI
Acronyms and Abbreviations. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. vii
Acknowledgments. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . VI11
1.0 Introduction. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1
2.0 Sample Analysis. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1
2.1 Sampling at Project RULISON, Colorado. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2
2.1.1 Water Analysis Results. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .4
2.1.2 Conclusions. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
2.2 Sampling at Project RIO BLANCO, Colorado. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
2.2.1 Water Analysis Results. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
2.2.2 Conclusions....... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
2.3 Sampling at Project F AUL TLESS, Nevada. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8
2.3.1 Water Analysis Results. . . . . . . . . . . . . . . ',' . . . . . . . . . . . . . . . . . . . . . . . 8
2.3.2 Conclusions................................................. 8
2.4 Sampling at Project SHOAL, Nevada. ... . . . .. . . . . . . . . . . .. . . . . . . . . . . .. . . .10
2.4.1 Water Analysis Results. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10
2.4.2 Conclusions........................ . . . . . . . . . . . . . . . . . . . . . . . . 12
2.5 Sampling at Project GASBUGGY, New Mexico. . . . . . . . . . . . . . . . . . . . . . . . . . . 12
2.5.1 Water Analysis Results. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13
2.5.2 Conclusions.................. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13
2.6 Sampling at Project GNOME, New Mexico. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15
2.6.1 Water Analysis Results. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ... 16
2.6.2 Conclusions............................................. . . . 16
References. . . . . . ~ . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .20
Glossary of Terms [[[ 21
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FIGURES
Pa~e
1. RULISON Site sampling locations for July2000 ................................... 3
2. RIO BLANCO Site sampling locations for July2000 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
3 . FAULTLESS Site sampling locations for March 2000 .............................. 9
4. SHOAL Site sampling locations for February 2000 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12
5. GASBUGGY Site sampling locations for June 2000 . . . . . . . . . . . . . . . . . . . . . . . . . . ., .. .15
6. GNOME Site sampling locations for June 2000. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18
TABLES
Page
1. Analysis Results for Water Samples Collected at RULISON Site - July 2000 ............4
2. Analysis Results for Water Samples Collected at RIO BLANCO Site - July 2000 ........ 7
3. Analysis Results for Water 'Samples Collected at FAULTLESS Site - March & July 2000 .10
4. Analysis Results for Water Samples Collected at SHOAL Site - February 2000 """'" 13
5. Analysis Results for Water Samples Collected at GASBUGGY Site - June 2000 ........16
6. Analysis Results for Water Samples Collected at GNOME Site - June 2000 ............ 19
VI
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AEC
DOE
DRI
RSL
EPA
DCG
g
3H+
3H
HpGe
lAG
keV
kg
KT
L THMP
L
m
nun
MDC
MeV
mL
MT
ORIA
pCi/L
PHS
R&IE
SGZ
USGS
IT
ACRONYMS AND ABBREVIATIONS
U.S. Atomic Energy Commission
U.S. Department of Energy
Desert Research Institute
Radiation Sciences Laboratory
U.S. Environmental Protection Agency
Derived Concentration Guide (20,000 pCi/L for Tritium in Drinking Water)
gram
Enriched Tritium
Tritium
high purity germanium gamma detector
Interagency Agreement
kilo electron volts (one thousand electron volts)
kilogram, 1000 grams
kiloton (one thousand tons TNT equivalent)
Long-Term Hydrological Monitoring Program
liter
meter
minute
minimum detectable concentration
one miJlion electron volts
milliliter (one thousandth of a liter)
megaton (one million tons TNT equivalent)
Office of Radiation and Indoor Air .
picocuries per liter = 10-12 curies per liter = 1/1,000,000,000,000 curies per liter
U.S. Public Health Service
Radiation and Indoor Environments National Laboratory, Las Vegas, NY
surface ground zero
U.S. Geological Survey
International Technology Corp.
Vll
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ACKNOWLEDGMENTS
The author would like to thank Rich Flotard, Rose Houston, Pat Honsa, Betty Strickland, and the
staff of the hydrological monitoring team, EP A, for their dedication to quality and tireless work
in the execution of the sampling and laboratory analysis effort. The author would also like to
thank Terry Mouck for her dedication and skill in word processing and desktop publishing
support which was crucial to the production of this report.
Vlll
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1.0 INTRODUCTION
Under an lAG with the DOE, the R&IE, fonnerly Radiation and Sciences Laboratory (RSL),
Office of Radiation and Indoor Air (ORIA), EPA located in Las Vegas, NV, conducts a Long-
Tenn Hydrological Monitoring Program (L THMP) to measure radioactivity concentrations in
water sources near the sites of fonner underground nuclear explosions. The results of the
L THMP provide assurance that radioactive materials from the tests have not migrated into
drinking water supplies. This report presents the results for the samples collected in February,
May, June, and July of 2000, around the following test site areas:
.
.
.
.
.
Project RULISON Test Site, Garfield County, Colorado
Project RIO BLANCO Test Site, Rio Blanco County, Colorado
Project FAULTLESS Test Site, Nye County, Nevada
Project SHOAL Test Site, Churchill County, Nevada
Project GASBUGGY Test Site; Rio Arriba County, New Mexico
Project GNOME Test Site, Eddy County, New Mexico
.
2.0 Sample Analysis
Radiochemical procedures used to analyze the samples collected for this report are described in
Johns, et al. (1979) and are summarized below (see Appendix for typical minimum detectable
concentration (MDC) values for gamma spectroscopy). These include standard methods to
identify natural and man-made gamma-emitting radionuclides, tritium, plutonium, strontium, and
uranium in water samples. Two types of tritium analyses were performed; conventional and
electrolytic enrichment. The enrichment method lowers the MDC from approximately 300
pCi/L to 5 pCi/L. An activity limit of activity of 800 pCiIL has been established for the
conventional method because sample cross contamination becomes a problem at higher levels.
In late 1995, it was decided that a maximum of 25 percent of all samples collected would be
analyzed by the low-level enrichment method. This decision was based on the time required for
analysis, budgetary constraints, and an assessment of past results. Under the current sampling
and analysis protocol for the site, all samples are initially screened for tritiuin activity by tP.e
conventional method, and selected samples are enriched. At this time only sampling locations
that are in a position to show migration are selected for enrichment.
Sufficient sample is collected from new sampling locations to perform all routine analyses, and a
full-suite of other radiochemical detenninations including assays for strontium, plutonium, and
uranIum.
I
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Summary of Analytical Procedures
Type of
Analysis
Analytical
Equipment
Counting
Period (Min)
Analytical
Procedures
Size of
Sample
Approximate
Detection Limit"
HpGe
Gammab
HpGe detector
calibrated at 0.5 keV/
channel (0.04 to 2 MeV
range) individual detector.
Efficiencies ranging from
15 to 35%.
-150
Radionuclide concen-
tration quantified from
gamma spectral data
by online computer
program.
3.5L
Varies with radionuclides
and detector used, if
counted to a MDC of
approx. 5 pCiIL for I37Cs.
JH
Automatic liquid
scintillation counter
300
Sample prepared by
distillation.
30 - 40 mL 300 to 700 pCiIL
3H+ Automatic liquid
Enrichment scintillation counter
300
Sample concentrated
by electrolysis following
distillation.
250 mL C S pCiIL
. The detection limit is dermed as the smallest amount of radioactivity that can be reliably detected, i.e.,
probability of Type I and Type II error at S percent each (DOE 1981).
b Gamma spectrometry using a high purity intrinsic germanium (HpGe) detector.
C Sample distilled, then concentrated to - Sml by electrolysis.
2.1 Sampling at Project RULISON, Colorado
History
Co-sponsored by the ABC and Austral Oil Company under the Plowshare Program, Project
RULISON was designed to stimulate natural gas r~covery in the Mesa Verde fonnation. The
test, conducted near Grand Valley, Colorado on September 10, 1969, consisted of a 40-KT
nuclear explosive emplaced at a depth of2,568 m (8,425 ft). Production testing began in 1970
and was completed in April 1971. Cleanup was initiated in 1972, and the wells were plugged in
1976. Some surface contamination resulted from decontamination of drilling equipment and
fallout from gas flaring. Contaminated soil was removed during the cleanup operations.
Sampling was conducted on July 12, 2000, from all sampling locations at Grand Valley and
Rulison, Colorado. Routine sampling locations are shown in Figure 1. Sampling included the
Grand Valley municipal drinking water supply springs, water supply wells for five local ranches,
and five sites in the vicinity of SGZ, including one test well, a surface-discharge spring and two
wells (RU-l and RU-2) located at SGZ.
2
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,
@)
e
I
Douglas K. Sauter Potter Ranch
Ranch
Grand Valley
City Springs
/
""'-\,,;
"'" - .
I
-., I
Rulison...J /
"",- --;
---,;"'" I
"'"
~ - - - - .... ,rI Tim Jacobs Ranch
I \ .Patrick Mc Carty
\ I ,
. I ., Battlement Creek
,,-.; .
DanielGardner CER ""-
Ranch Test Well - Spring
RU-1 .0
RU-2.
~
N
o Surface Ground Zero
I Water Sampling Locations
- - - Unpaved Road
LOCATION MAP
Scale In Miles
o 5
..-~
o
Scale in Kilometers
GARFIELD
COUNTY
8
Figure 1. RULISON Site sampling locations for July 2000.
3
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2.1.1 Water Analysis Results
Tritium has never been observed in measurable concentrations in the Grand Valley City Springs.
All of the remaining sampling sites show detectable levels of tritium, which have generally
exhibited a stable or decreasing trend over the last two decades. The range of tritium activity in
2000 was from 32:!: 4.3 pCi/L at RU-1 to 66:!: 4.3 pCi/L at Patrick McCarty Ranch (see Table
1). All enriched values were less than 0.5 percent of the DCG (20,000 pCi/L). The detectable
tritium activities are consistent with values found in current precipitation and, perhaps, a small
residual component remaining from clean-up activities at the site. This is supported by Desert
Research Institute analysis, which indicates that most of the sampling locations at the RULISON
site are shallow, drawing water from the surficial aquifer, and therefore, unlikely to become
contaminated by radionuclide migration from the Project RULISON cavity (Chapman and
Hokett, 1991).
Analysis Results for Water Samples Collected at RULISON Site - Julv 2000
TABLE 1
~~1~;;:I~j;~i'!,;~t~:~~ '~~~~JJ~.l~g~I~"i~~!~f~ ;,%!i£~f~~1r~
Battlement Creek 7/12/00 12.5:1: 122 (201) ND (4.9)
City Springs 7/12/00 112:1: 124 (201) ND (4.4)
David Gardner 7/12/00 62:1: 123 (201) ND (4.8)
(4.8)
(5.0)
(4.7)
(4.6)
(5.0)
(4.8)
CER Test Well 7/12/00 112:1: 124 (201) ND
Patrick McCarty 7/12/00 66.7:1: 4.3 (5.0) ND
Potter Ranch 7/12/00 74.9:1: 123 (201) ND
Douglas Sauter 7/12/00 104:1: 124 (20 1) ND
Tim Jacobs 7/12/00 37.4:1: 123 (201) ND
Spring 300 yds N. 7/12/00 99:1: 124 (201) ND
ofGZ
Well RU-l 7/12/00 32:1: 4.1 (5.7) ND
Well RU-2 7/12/00 74.9:1: 123 (201) ND
Well RU-3 7/12/00 30.9:1: 3.8 (5.1) ND
(4.6)
(4.9)
(4.9)
(a) Indicate results are less than MDC (enriched or conventional method).
(b) Value in parenthesis represents \37Cs MDC (pC ilL).
ND Non-detected.
4
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2.1.2 Conclusions
Tritium concentrations in water samples collected onsite and offsite are consistent with those of
past studies at the RULISON Test Site. In general, the current level of tritium in shallow wells at
the RULISON site cannot be distinguished from the rain-out of naturally produced tritium
augmented by, perhaps, a small amount of residual global "fallout tritium" remaining from
nuclear testing in the 1950s and 1960s. All routine samples were analyzed for presence of
gamma-ray emitting radionuclides. None were detected above the:MDC (see Table 1, page 4).
2.2 Sampling at Project RIO BLANCO, Colorado
History
Project RIO BLANCO a joint government-industry test designed to stimulate natural gas flow
was conducted under the Plowshare Program. The test was conducted on May 17, 1973, at a
location between Rifle and Meeker Colorado. Three explosives with a total yield of 99 KT were
emplaced at 1,780, 1,920, and 2,040 m (5,840,6,299, and 6,693 ft) depths in the Ft. Union and
Mesa Verde formations. Production testing continued until 1976 when cleanup and restoration
activities were completed. Tritiated water produced during testing was injected to 1,710 m
(5,610 ft) in a nearby gas well.
Sampling was conducted on July 13-14,2000, and locations are shown in Figure 2. The routine
sampling locations included four springs, four surface, and five wells, three of which are located
near the cavity. At least two of the wells (Wells RB-D-01 and RB-D-03) are suitable for
monitoring because they were down gradient and would indicate possible migration of
radioactivity from the cavity.
2.2.1 Water Analysis Results
Gamma-ray spectral analysis results indicated that no man-made gamma-ray emitting
radionuclides were present in any offsite samples. None of the 15 samples collected were above
the MDC for enriched tritium. This year Well RB- W -01 was not sampled, as it was inaccessible
(see Table 2, page 7).
2.2.2 Conclusions
Tritium concentrations in water samples collected onsite and off site are consistent with those of
past studies at the RIO BLANCO Site. No radioactive materials attributable to the RIO
BLANCO test were detected in samples collected in the offsite areas during July 2000. All
samples were analyzed for presence of gamma-ray emitting radionuclides. None were detected
above the MDC.
5
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Fawn Cr.500'
Upstream
Fawn Cr. 6800'
Upstream
. Fawn Cr.500' Downstream
. RB-D-O 1 }
RB-D-03 4
RB-S-03
RB-W-01
. Fawn Cr. NO.3
Scale In Miles
0 5
~ ..,
o 8
Scale In Kilometers
RIO BLANCO COUNTY
-------------------------------
GARFIELD COUNTY
o Surface Ground Zero
. Water Sampling Locations
,
N
LOCATION MAP
RIO BLANCO
COUNTY
Figure 2. RIO BLANCO Site sampling locations for July 2000.
6
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Analysis Results for Water Samples Collected at RIO BLANCO Site - July 2000
TABLE 2
Sample Collection Enriched Tritium Tritium(a) Gamma Spectrometry(b)
Location Date pCilL :I: 2 SD (MDC) pCiIL :I: 2 SD (MDC) pCi/L (MDC)
B-1 Equity Camp 7/14/00 117:!: 124 (201) ND (5.0)
Brennan Windmill 7/13/00 -66.6:1: 120 (201) ND (4.9)
CER #1 Black 7/14/00 25 :I: 122 (201) ND (4.6)
Sulphur
CER #4 Black 7/14/00 -16.6:1: 121 (210) ND (4.9)
Sulphur
Fawn Creek # 1 7/13/00 45.8:1: 123 (201) ND (4.7)
Fawn Creek #3 7/13/00 -29.1 :I: 121 (201) ND (4.9)
Fawn Creek 500' 7/14/00 -66.6:1: 120 (201) ND (4.9)
Upstream
Fawn Creek 6800' 7/13/00 -45.8:1: 121 (201) ND (4.6)
Upstream
Fawn Creek 500' 7/14/00 20.8 :I: 122 (201) ND (4.7)
Downstream
Fawn Creek 8400' 7/14/00 8.3 :I: 122 (201) ND (4.8)
Downstream
Johnson Artesian 7/13/00 -95.7:1: 120 (201) ND (4.9)
Well
Well RB-D-Ol 7/13/00 3.3 :I: 3.0 (a) (4.8) -22:1: 127 (201) ND (4.6)
Well RB-D-03 7/13/00 18:1: 128 (201) ND (4.8)
Well RB-S-03 7/14/00 3.7:1: 3.1 (a) (4.9) ND (4.7)
Well RB-W-01 7/14/00 Not Sampled
(a) Indicate results are less than MDC (enriched or conventional method).
(b) Value in parenthesis represents I37Cs MDC (pC ilL).
ND Non-detected.
7
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2.3 Sampling at Project FAULTLESS, Nevada
History
Project FAULTLESS was a "calibration test" conducted on January 19, 1968, in a sparsely
populated area near Blue Jay Maintenance Station, Nevada. The test had a yield of less than 1
MT and was designed to test the behavior of seismic waves and to determine the usefulness of
the site for high-yield tests. The emplacement depth was 975 m (3,200 ft). A surface crater was
fanned, but as an irregular block along local faults rather than as a saucer-shaped depression.
The area is characterized by basin' and range topography, with alluvium overlying tuffaceous
sediments. The working point of the test was in tuff. The groundwater flow is generally from
the highlands to the valley and through the valley to Twin Springs Ranch and Railroad Valley
(Chapman and Hokett, 1991).
Sampling was conducted in March and July 2000. Sampling locations are shown in Figure 3.
They include one spring and six wells of varying depths. A new well was added in March 2000.
This well is located at Twin Springs Ranch.
At least two wells (HTH-1 and HTH-2) are positioned to intercept migration from the test cavity,
should it occur (Chapman and Hok€?tt, 1991). All samples yielded negligible gamma activity.
Enriched tritium concentrations were less than the MDC and less than 0.02 percent of the DCG.
These results were all consistent with results obtained in previous years. The consistently below-
MDC results for tritium indicate that, to date, migration into the sampled wells has not taken
place and no event-related radioactivity has entered area drinking water supplies.
2.3.1 Water Analysis Results
All gamma-ray spectral analysis results indicated that no man-made gamma-ray emitting
radionuclides were present above minimum detectable levels in any offsite samples. All tritiuni
results were below the MDC (see Table 3, page 10).
2.3.2 Conclusions
Tritium concentrations of water samples collected onsite and off site are consistent with those of
past studies at the F AUL TLESS Site. No gamma-ray emitting radionuclides were detected above
the MDC.
8
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I
/
0/
.. HTH 2
\. HTH 1
\
.
I
J
,,"/
,,; /
/ ,," I
/ " I
" ,
, ,,-,- ,," I
r ,--, " \
. ',,," \
I '..... " \
HclCre~ ~ \
Ranch Spring .
. Six-Mile Well
.
.
I
I
I
I
,
,
,
I
I
I
I
I
I
I
I
I
.
I
~
N
SiteC
Complex
. Twin Springs Ranch
Blue Jay
Maintenance
Station
o Surface Ground Zero
. Water Sampling Locations
Scale in Miles
o
I
o
5
~
5
Scale in Kilometers
Figure 3. FAULTLESS Site sampling locations for March 2000.
9
10
NYE
COUNTY
LOCATION MAP
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A I
S
I C II t d t FAULTLESS S'
M
h & J I 2000
nalysis Results for Water amples 0 ec e a Ite - arc uly .
TABLE 3
Sample Collection Enriched TritiumCa) TritiumCa) Gamma Spectrometry(b)
Location Date pCiIL :J: 2 SD (MDC) pCiIL :!:: 2 SD (MDC) pCiIL (MDC)
Hot Creek Ranch 3/14/00 6.2:J: 127 (209) ND (4.9)
Spring
Blue Jay Maint 3/13/00 -44.8:!:: 126 (209) ND (1.7)
Station
Well HTH-l 3/14/00 -.75 :J: 3.2 (5.2) ND (4.5)
Well HTH-2 7/26/00 -4.6:J: 3.3 (5.1) ND (4.8)
Site C Complex 3/13/00 -117:J: 124 (209) ND (4.6)
Six Mile 3/14/00 Not Sampled
Twin Springs 3/14/00 -2.4:!:: 3.5 (5.8) ND (1.6)
Ranch
(a) Indicate results are less than MDC (enriched or conventional method).
(b) Value in parenthesis represents \J1Cs MDC (pCiIL).
ND Non-detected.
2.4 Sampling at Project SHOAL, Nevada
History
Project SHOAL, a 12-KT nuclear test emplaced at 365 m (1,204 ft), was conducted on
October 26, 1963, in a sparsely populated area near Frenchman Station, Nevada, 28 miles
southeast of Fallon, Nevada. The test, a part of the Vela Uniform Program, was designed to
investigate detection of a nuclear detonation in an active earthquake zone. The working point
was in granite and no surface crater was created. The effluent released during drillback was
detected onsite only and consisted of 110 curies of 13IXe and 133Xe, and less than 1.0 curie of 1311.
Samples were collected on February 15 through 17, 2000. The sampling locations are shown in
Figure 4. Only eight of the nine routine locations were sampled. Since 1997, eight new wells
have been added to the L THMP at this site which are positioned near GZ. Two of the eight new
wells drilled at Shoal in 1999 were designed for conducting a tracer test. Previous modeling of
the site found that the effective porosity of the aquifer was a very important, but highly uncertain,
parameter. The purpose of the tracer test is to determine the effective porosity of the fractured
granite aquifer. The test was conducted in two' phases. The initial, smaller, injection consisted of
iodide, carbon-13, and deuterium and occurred on November 3, 1999. Its primary purpose was
to provide information for the major injection. The majorinjection occurred on November 10,
1999, and consisted oflithium, bromide, and poly-fluorinated benzoic acid. On November 28,
1999, cesium was injected, and in June 2000, polystyrene micro spheres were" injected. The
breakthrough has been slow, leading to an extension of the test beyond its planned four-month
time period to the end of the federal fiscal year (September 2000). Both the injection well, HC-6,
and pumping well, HC-7, are likely to contain remnants from the tests for some time to come.
10
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The routine sampling locations include one spring, one windmill, and seven wells of varying
depths. At least one location, Well HS-l, should intercept radioactivity migrating from the test
cavity, if it occurs (Chapman and Hokett 1991).
2.4.1 Water Analysis Results
Analysis of a well sample from the Shoal Site collected in February 2000, (Well HC-3, sample
#72839) has brought to light a potential problem in this program. Apparently, because of fairly
significant sediment loading, this sample, as received in the lab, assayed at about 19 pCi/L for
natural uranium (U-234+U-235+U-238). It should also be noted that these fairly unusual results
occurred even though the sample was filtered in the laboratory prior to analysis. Even more
intriguing, an un-acidified sample collected from this well at the same time for tritium analysis
showed only - 3 pCi/L of natural uranium.
The difference between the two results is probably due to differences in the collection processes.
Specifically, the sample collected for radiochemistry was acidified with nitric acid; the second
sample, collected as a spare for tritium analysis, was not. Apparently the acid added to the
radiochemistry sample leached uranium from the sediments in the sample. Subsequent filtering
in the laboratory removed the bulk of the uranium-containing sediment from the sample but
would of course, not be effective in removing what is now dissolved uranium.
One could make the point that some radionuclides in the un-acidified sample might have plated
out on the sides of the glass sample bottle - i.e, if the results for the field acidified sample are too
high those for the un-acidified sample may be too low. This is not likely for uranium as long as
dissolved oxygen and complexing anions, like carbonates, are present. Only re-sampling would
sort out the true in-situ "dissolved" uranium content of the water in this well.
In 1987, it was decided that field filtering of water samples was unnecessary and the practice was
discontinued. Prior to the annual water sampling in 2001, the issue of filtering water samples
will be addressed by DOE and EPA. We recommend that any water sample that shows visible
amounts of sediment should be filtered in the field before being acidified with nitric acid. This
would also be prudent for any new sampling location and would prevent uncertainty of the type
encountered in the analysis of this sample. Standard treatment for ground-water samples
submitted for inorganic analysis is filtration through a 0-:45 micron filter before acidification. For
examples, Gelman Scientific makes a 0.45 micron filtration cartridge that is used by a lot of
environmental/hydrology groups. A single filter cartridge used on a battery-operated peristaltic
pump or pressurized tank. system is sufficient to filter several gallons of water in the field and the
used filters should probably be saved in case analysis of the water indicates something
unexpected.
As a final note, the "as received" gross alpha result for this sample would probably exceed the
Safe Drinking Water Standard of 15 pCiIL (alpha), which could trigger further, and probably un-
necessary work, based on a sampling artifact. Because we initially analyzed this sample for
uranium (one of the SDW A follow-up analyses for samples that exhibit high alpha activity), we
are fairly confident the source of the elevated activity is largely due to the leaching of uranium-
containing sediments in the sample by acid added at the time of collection.
11
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,
,
, , CHURCHILL COUNTY
--------------------------___--_1
MINERAL COUNTY
Fallon
95
. Flowing Well
Well H-3 .
,
,
(J.: "
01- ,
°o ,
~ ,
~
HC-5 .
-----
To Scheelite Mine
Scale in Miles
o 5
.--.,
o
10
~
15
.0 Surface Ground Zero
. Water Sampling Locations
5 10
Scale In Kilometers
Figure 4. SHOAL Site sampling locations for February 2000.
12
. HS-1
~
N
LOCATION MAP
-------
Gamma-ray spectral analysis results indicated that no man-made gamma-ray emitting
radionuclides were present in any samples above the MDC. Tritium concentration at all the
locations were 'below the MDC (see Table 4, below).
2.4.2 Conclusions
No radioactive materials attributable to the SHOAL nuclear test were detected in samples
collected in the offsite areas during 2000.
Analysis Results for Water Samples Collected at SHOAL Site - February 2000
;: ;!;~:t.:~:.~}~;;~.:;~.:~:; :~.::~ ::. .:.....,. '.";
~~~~~~?,:'5,:,:,:,::"'i
TABLE 4
!!~1~~I~lf~!~t!!ifil~ti]!~if~' !;~~!i~i.;
Hunts Station 2/15/00
Flowing Well 2/15/00
Well H-2 2/17/00
Well H-3 2/15/00
Well HS-1 2/17/00
Well HC-1 2/17/00
Well HC-2 2/17/00
Well HC-3 2/16/00
Well HC-4 2/15/00
Well HC-5 2/15/00
Well HC -7 2/15/00
Well HC-8 2/17/00
.75 :i:2.9
79:i: 123
105:i: 124
66.2:i: 123
57.7:i: 123
(4.8)
147:i: 125
49 :i: 878
(4.8)
1.8 :i: 2.9
442 :i: 708
0.2:i: 3.2
2.9:i: 3.3
(5.2)
(5.2)
( 5.4)
-0.6 :i: 3.3
(a) Indicate results are less than MDC (enriched or conventional method).
(b) Value in parenthesis represents I37Cs MDC (pCi/L).
ND Non-detected.
(200) ND (3.0)
(200) ND (3.2)
(200) ND (3.1)
(200) ND (3.8)
ND (3.3)
(200) ND (3.1 )
(200) ND (3.3)
ND (3.2)
(200) ND (3.1)
ND (3.1)
ND (3.8)
ND (3.7)
2.5 Sampling at Project GASBUGGY, New Mexico
History
Project GASBUGGY was a Plowshare Program test co-sponsored by the U.S. Government and
£1 Paso Natural Gas Co., conducted near Gobemador, New Mexico, on December 10, 1967. A
nuclear explosive with a 29-KT yield was detonated at a depth of 1,290 m (4,240 ft) to stimulate
13
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a low productivity natural gas reservoir. Production testing was completed in 1976 and
restoration activities were completed in July 1978.
The principal aquifers near the test site are the Ojo Alamo Sandstone, an aquifer containing non-
potable water located above the test cavity, and the San Jose formation and Nacimiento
formation.
Both surficial aquifers contain potable water. The flow regime of the San Juan Basin is not well
known, although it is likely that the Ojo Alamo Sandstone discharges to the San Juan River 50
miles northwest of the Gasbuggy site. Hydrologic gradients in the vicinity are downward, but
upward gas migration is possible (Chapman and Hokett, 1991).
Annual sampling at Project GASBUGGY was completed during June 8 -10,2000. All of the
routine sampling locations were collected (see Figure 5).
2.5.1 Water Analysis Results
The Cedar Springs sampling site yielded enriched tritium activities of 35 ~ 3.8 pCi/L which is
less than 0.5 percent of the DCG and similar to the range seen in previous years. Tritium samples
from the other locations were all below the average MDC.
Well EPNG 10-36 has yielded tritium activities between 100 and 560 pCi/L in each year since
1984, except in 1987. The sample collected in June 2000, yielded a tritium activity of 88 ~ 5.0
pCi/L. The migration mechanism and route are not currently known, although an analysis by
Desert Research Institute indicated two feasible routes, one through the Printed Cliffs sandstones,
and the other one through the Ojo Alamo sandstone, one of the principal aquifers in the region
(Chapman 1991). In either case, fractures extending from the cavity may be the primary or a
contributing mechanism. The proximity of the well to the test cavity suggests the possibility that
the activity increases may indicate migration from the test cavity.
All gamma-ray spectral analysis results indicated that no man-made gamma-ray emitting
radionuclides were present in any off site samples above minimum detectable levels.
2.5.2 Conclusions
Tritium concentrations of water samples collected onsite and offsite are consistent with those of
past studies at the GASBUGGY Site.
14
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Bixler Ranch. '
. Pond N. of
. Well 30.3.32.343N
Well 30.3.32.343N
. Well 28.3.33.233S
Cedar Springs.
Cave Springs.
Arnold Ranch Spring
Arnold Ranch Well
J.10
~
N
Scale in Miles
o 5
...-~
o Surface' Ground Zero
. Water Sampling Locations
o
Scale in Kilometers
Figure 5. GASBUGGY Site sampling locations for June 2000.
15
LOCATION MAP
8
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A I . R
I ~ W
S
I
C II t d t GASBUGGY S't
J
2000
nalYSIS esu ts or ater amples 0 ec e a 1 e - une
TABLE 5
Sample Collection Enriched Tritium Tritium(.) Gamma Spectrometry(b)
Location Date pCiIL 1: 2 SD (MDC) pCiIL 1: 2 SD (MDC) pCiIL (MDC)
Arnold Ranch 6/10/00 -7 1: 110 (181) ND (4.7)
Spring
Bubbling Springs 6/09/00 -62 1: 108 (181) ND (4.9)
Cave Springs 6/09/00 40 1: 109 (181) ND (4.6)
Cedar Springs 6/08/00 35.31: 8.8 (5.1) ND (4.8)
La Jara Creek 6/08/00 -69 1: 108 (181) ND (4.9)
Lower Burro 6/08/00 -73 1: 108 (181) ND (4.5)
Canyon
Pond N. of Well 6/09/00 73 1:111 (181) ND (4.5)
30.3.32.343
Well EPNG-10-36 6/08/00 88.31:5.0 (5.6) ND (5.0)
Jicarilla WeIll 6/08/00 -66 1: 108 (181) ND (4.9)
Well 28.3.33.233 6/08/00 -77 1: 108 (181) ND (4.6)
(South)
Well 30.3.32.343 6/08/00 -44 1: 109 (181) ND (4.7)
(North)
Windmill #2 6/10/00 -4 1: 110 (181) ND (4.7)
Arnold Ranch 6/10/00 -55 1: 108 (181) ND (4.9)
Well
(a) Indicate results are less than MDC (enriched or conventional method).
(b) Value in parenthesis represents \J7Cs MDC (PCiIL).
ND Non-detected.
2.6 Sampling at Project GNOME, New Mexico
Project GNOME, conducted on December 10, 1961, near Carlsbad, New Mexico, was a
multipurpose test emplaced at a depth of 1,216 ft in the Salado salt fonnation. The explosive
yield was slightly-more-than 3-KT. Oil and gas are produced from the geologic units below the
working point. The overlying Rustler formation contains three water-bearing zones: brine
located at the boundary of the Rustler and Salado formations, the Culebra Dolomite which is
used for domestic and stock supplies, and the Magenta Dolomite which is above the zone of
saturation (Chapman and Hokett, 1991). The ground water flow is gene~ally to the west and
southwest.
16
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Radioactive gases were accidentally vented following the test. In 1963, USGS conducted a tracer
study involving injection of20 Ci tritium, 10 Ci 137CS, 10 Ci 90Sr, and 4 Ci 1311 in the Culebra
Dolomite zone; using Wells USGS 4 and 8. During remediation activities in 1968-69,
contaminated material was placed in the test cavity and the shaft up to within 7 ft of the surface.
More material was slurried into the cavity and drifts in 1979. A potential exists for discharge of
this slurry to the Culebra Dolomite and to Rustler-Salado brine. Potentially this may increase as
the salt around the cavity compresses, forcing contamination upward and distorting and cracking
the concrete stem and grout.
Annual sampling at Project GNOME was completed during June 2000. The routine sampling
sites, depicted in Figure 6, include ten monitoring wells in the vicinity of surface GZ; the
municipal supplies at Loving and Carlsbad, New Mexico.
2.6.1 Water Analysis Results
No tritium activity was detected in the Carlsbad municipal supply or the Loving Station well. An
. analysis by Desert Research Institute (Chapman and Hokett, 1991) indicates that these sampling
locations, which are on the opposite side of the Pecos River from the Project GNOME site, are
not connected hydrologically to the site and, therefore, cannot become contaminated by Project
GNOME radionuclides.
Tritium results greater than the MDC were detected in water samples from four of the 12
sampling locations in the immediate vicinity ofGZ. Tritium activities in wells DD-l, LRL-7,
USGS-4, and USGS-8 ranged from 4.5 x 107 (DD-l) to 1.7 x 103 (LRL-7) pCi/L. Well DD-l
collects water from the test cavity; Well LRL-7 collects water from a sidedrift; and Wells USGS-
4 and USGS-8 were used in the radionuclide tracer study conducted by the USGS. None of these
wells are sources of potable water.
In addition to tritium, 137Cs and 90Sr concentrations were observed in samples from of Wells DD-
1, LRL-7, and USGS-8, while 90Sr activity was detected in Well USGS-4 as in previous years
(see Table 7). No tritium was detected in the remaining sampling locations, including Well
USGS-I, which the DR! analysis (Chapman and Hokett 1991) indicated is positioned to detect
any migration of radioactivity from the cavity. All other tritium results were below the MDC.
2.6.2 Conclusion
No radioactive materials attributable to the GNOME Test were detected in samples collected in
the offsite areas during June of2000.
17
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Carls bad
Carlsbad
City .
Well?
.
Loving City
Well 2
+
N
PHS Well 6 .
PHS Well 9 .
.
PHS Well 10
. PHS Well 8
Scale In Miles
o 5 10
~
o 5 10 15
Scale in Kilometers
EDDY
COUNTY
o Surface Ground Zero
. Water Sampling Locations
Figure 6. GNOME Site sampling locations for June 2000.
18
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Tritium Results for Water Samples Collected at GNOME Site - June 2000
TABLE 6
Sample Collection Enriched Tritium Tritium Gamma SpectrometryCb)
. Location Date pCiIL :%: 2 SD (MDC) pCiIL: 2 SD (MDC) pCiIL (MDC)
Well 7 City 6/13/00 -1.10:%: 107 (181) ND (5.0)
Well 2 City 6/13/00 4.2:%: 3.5 (a) (5.6) ND (5.0)
PHS 6 6/14/00 -18.3:J: 109(a) (181) ND (4.6)
PHS 8 6/14/00 3.7 :J: 110 (a) (181) ND (4.9)
PHS 9 6/15/00 -54.9:J: 109(a) (181) ND (4.1)
PHS 10 6/14/00 -14.6:J: 109(a) (181) ND (4.9)
USGS WeIll 6/13/00 -1.7:J: 3.0 (a) (5.0) ND (4.9)
USGS Well 4 6/14/00 7.4 x 104:J: 748 (181) ND (1.5)
Well USGS 8 6/14/00 5.7 x 104:J: 538 (181) Cs-137
73.4:%: 9.1 (1.54)
1. Mobley Ranch 6/13/00 3.7:J: 3.5 (a) (5.5) ND (5.0)
Well DD-1 6/15/00 4.5 x107 :%: 1.2 x10s Cs-137 (4.2x1 03)
6.7xlOs:J: 1.2xlO 5
LRL-7 6/15/00 1.7x103 :%: 142 (181) Cs-137
27.8 :%: 4.8 (4.9)
(a) Indicate results are less than MDC (enriched or conventional method).
(b) Value in parenthesis represents 137Cs MDC (pCiIL).
ND Non-detected.
19
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REFERENCES
Chapman & Hockett, 1991. Evaluation 01 Groundwater Monitoring at Offsite Nuclear Test
Areas, Las Vegas, NY, Desert Research Institute, University of Nevada System, Report
DOEINV /10845-07.
Code of FederaI Regulations, Vol. 41, title 40, Part 141, July 9, 197Q, National Interim Primary
Drinking Water Regulations.
A Guide for Environmental Radiological Surveillance at US. Dept. of Energy Installations, July
1981, Office ofOperationaI Safety Report. Las Vegas, NY: U.S. Department of Energy;
DOE/EP-0023.
Johns, F., et aI. 1979. Radiochemical and Analytical Procedures for Analysis of Environmental
Samples. Las Vegas, NY: U.S. Environmental Protection Agency; EMSL-L V-0539-17-1979.
Offsite Environmental Monitoring Report Radiation Monitoring Around Nuclear Test Areas,
Calendar Year 1992. EP A 600/R-94/209.
20
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GLOSSARY OF TERMS
Background Radiation
The radiation in man's environment, including cosmic rays and radiation from naturally-
occurring and man-made radioactive elements, both outside and inside the bodies of humans and
animals. The usually quoted average individual exposure from background radiation is 12S
millirem per year in mid-latitudes at sea level.
Curie (Ci)
The basic unit used to describe the rate of radioactive disintegration. The curie is equal to 37
billion disintegrations per second, which is the equivalent of 1 gram of radium. Named for Marie
and Pierre Curie who discovered radium in 1898. One microcurie (!lCi) is 0.000001 Ci.
Isotope
Atoms of the same element with different numbe~s of neutrons in the nuclei. Thus 12C, 13C, and
14C are isotopes of the element carbon, the numbers denoting the approximate atomic weights.
Isotopes have very nearly the same chemical properties, but have different physical properties
(for example 12C and 13C are stable, 14C is radioactive).
Enrichment Method
A method of electrolytic concentration that increases the sensitivity of the analysis of tritium in
water. This method is used for selected samples if the tritium concentration is less than 700
pCi/L.
Minimum Detectable Concentration (MDC)
The smallest amount of radioactivity that can be reliably detected with a probability of Type I
and Type II errors at 5 percent each (DOE 1981).
Offsite
Areas exclusive of the immediate Test Site Area.
Type I Error
The statistical error of accepting the presence of radioactivity when none is present. Sometimes
called alpha error.
Type II Error
The statistical error of failing to recognize the presence of radioactivity when it is present.
Sometimes called beta error.
21
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Appendix
Typical MDA Values for Gamma Spectroscopy
(100 minute count time)
Geometry *
Matrix
Volume
Isotope
Be-7
K-40
Cr-51
Mn-54
Co-57
Co-58
Fe-59
Co-60
Zn-65
Nb-95
Zr-95
4.56E+01
4.92E+01
5.88E+01
4.55E+01
9.65E+00
4.71E+00
1.07E+01
5.38E+00
1.24E+01
5.64E+00
9.06E+00
Model 430G
Density 1.0 g/ml
Units pC ilL
Isotope MDA
Ru-106 4.76E+01
Sn-113 8.32E+OO
Sb-125 1.65E+01
1-131 8.28E+OO
Ba-133 9. 16E+OO
Cs-134 6.12E+OO
Cs-137 6.43E+OO
Ce-144 7.59E+01
Eu-152 2.86E+01
Ra-226 1.58E+01
U-235 1.01E+02
Am-241 6.60E+01
Marinelli
Water
3.5 liter
MDA
Disclaimer
The MDA's provided are for background matrix samples presumed to contain no known analytes and no
decay time. All MDA's provided here are for one specific *Germanium detector and the geometry of
interest. The MDA's in no way should be used as a source of reference for determing MDA's for any
other type of detector. All gamma spectroscopy MDA's will vary with different tYpes of shielding,
geometries, counting times and decay time of sample.
22
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