&EPA
           United States
           Environmental Protection
           Agency
           Environmental Monitoring
           Systems Laboratory
           P.O. Box 93478
           Las Vegas NV 89193-3478
EPA 600/4-91/031
November 1991
           Research and Development
Environmental Monitoring
Report

Radiation Monitoring
On and Around the
Tatum Salt Dome,
Lamar County, Mississippi
April 1991
                                        1238mPB91 rpt

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     Radiation  Monitoring On and
Around the Tatum Salt Dome,  Lamar
           County, Mississippi
                 April 1991
                       by

                    D. J. Thome*
                    S. H. Faller
                    C. A. Fontana
                    C. F. Costa

              Environmental Protection Agency
                   P.O. Box 93478
                Las Vegas, NV 89193-3478
                prepared for the U.S. DOE
                under Interagency Agreement
                 DE-A108-86NV10522
       ENVIRONMENTAL MONITORING SYSTEMS LABORATORY
          OFFICE OF RESEARCH AND DEVELOPMENT
          U.S. ENVIRONMENTAL PROTECTION AGENCY
               LAS VEGAS, NV 89193-3478
                                               1238mPB91.rpt

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                                         NOTICE
       The information in this document has been funded wholly or in part by the United States Environ-
mental Protection Agency through Interagency Agreement DE-A108-91NV10963 from the United States
Department of Energy.  It has been subject to the Agency's peer and administrative review, and it has been
approved for publication as an EPA document.
       Mention of trade names or commercial products does not constitute endorsement or recommendation
for use.

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                                         ABSTRACT
       In 1964, and again in 1966 a nuclear explosive was detonated approximately 2700 feet underground
in the Tatum Salt Dome located in Lamar County, Mississippi. Drilling and cleanup activities have resulted
in tritium contamination in close proximity to the surface ground zero.  The Long-Term Hydrological
Monitoring Program conducted by the U.S. Environmental Protection Agency consists of annual water
sampling on and around the Tatum Salt Dome.  In 1991, in addition to water sampling, a gamma-ray
characterization study was conducted.
       As in past years no radioactive materials from the Tatum Salt Dome were detected in any water
samples collected offsite. The highest tritium concentration found in water collected in the offsite area was
48 pCi/1. This is from natural sources and is 0.24 percent of the National Interim Primary Drinking Water
Regulations (40CFR141) which places the maximum level of tritium in drinking water to be 20,000 pCi/1. The
highest tritium concentration found onsite was 14,000 pCi/1. This concentration was detected in water samples
collected in two wells, Well HMH-1 and Well HMH-2. These wells are both less than 10 feet deep and they
are located very near to the surface ground zero. The water from these wells is not available to the public nor
suitable for drinking due to its brackishness.
       The gamma-ray characterization study consisted of eight locations onsite and four offsite. The study
showed good agreement between exposure rates derived from in-situ gamma-ray spectrometry and those
measured with a pressurized ion chamber in all locations surveyed. Variabilities of gamma flux contributed
by radionuclides in the soil were small with the exception of 137Cs, which was lower than expected in all onsite
locations. The 137Cs is the result of global fallout from atmospheric nuclear testing.
                                              in

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                                       CONTENTS
                                                                                     Page
Abstract	iii
Figures	vii
Acknowledgments	viii

Introduction	1
History	1
Monitoring Results: Historical Summary	1
Calendar Year 1991 Monitoring Results	5
Water	5
Sample Analysis Procedures	8
Water Analysis Results	8
Gamma-Ray Characterization Study	11
Gamma-Ray Characterization Results	11
Conclusion	12
References	13

Appendices

1      Abbreviations	14
2      Glossary of Terms	15
3      Summary of Analytical Procedures	16
4      Results for Water Samples Collected in April 1991	17
5      Exposure Rate Inventories at all Survey Locations	24
6      Soil Sample Study	25

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                                         FIGURES
Figure Number	Page


1    General site location	2
2    Topographic map of the Tatum Dome Test Area showing the Surface Ground Zero and
     outline of Salt Dome at 2,700 feet below land surface	3
3    Test cavity and aquifers	4
4    Plots of tritium concentrations vs. time	6
5    Locations in the vicinity of surface ground zero sampled and monitored in 1991	9
6    Offsite locations sampled in 1991	10
                                             VI

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                                 ACKNOWLEDGMENTS
       The authors would like to acknowledge Mr. M.G. Davis for his dedication to quality and his tireless
work in the design and execution of the sampling effort. We also want to thank Ms. D.J. Chaloud for her
suggestions, editorial expertise, and for bringing this document to fruition.
                                            VII

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                                       INTRODUCTION
      Under an Interagency Agreement with the U.S.
 Department of Energy (DOE), the Environmental
 Monitoring Systems Laboratory (EMSL-LV) of the
 U.S. Environmental Protection Agency (EPA) located
 in Las Vegas, NV, conducts a Long-Term Hydro-
 logical Monitoring Program (LTHMP) to measure
 radioactivity  concentrations in water sources near
 the sites of underground nuclear explosions. The
 results of the  LTHMP provide assurance that radio-
 active materials from the tests have not migrated into
 drinking water supplies.  This report presents the
 results for the samples collected in April 1991, on
 and around the Tatum Salt Dome, in Lamar County,
 Mississippi.

 History

     Project Dribble, consisting of two nuclear ex-
 plosions, and Project Miracle Play, consisting of two
 non-nuclear gas explosions, were conducted in the
 Tatum Salt Dome, near Baxterville, Lamar County,
 Mississippi, between 1964 and 1970. The general
 area is depicted in Figure 1. This area is called the
 Tatum Dome Test Area (Figure 2) and contains
 approximately 1470 acres located in Sections 11,12,
 13 and 14, Township 2 North, Range 16 West.
Event Date  Name
10-22-64    Salmon        Nuclear
12-03-66    Sterling        Nuclear
02-02-69    Diode Tube    Gas
04-19-70    Humid Water  Gas
Yield
 5.3
 0.38
 0.32
 0.32
     These tests were part of the Vela Uniform
program of the U.S. Atomic Energy Commission
(now the DOE). The purpose of the tests was to study
the decoupling principle, i.e., to measure and evalu-
ate the phenomena of seismic waves that are induced
from the explosions as compared to those that occur
naturally from earthquakes.
     The first explosion, the Salmon Event, created
a cavity in the Tatum Salt Dome that was used for the
 other three explosions. The top of the cavity is 1,160
 feet (360 m) below the top of the salt dome. The top
 of the salt dome is another 1,500 feet (460 m) below
 the land surface (Figure 3).
     At the Project Dribble site, disposal of drilling
 muds and fluids near surface ground zero (SGZ)
 resulted in onsite contamination of shallow ground
 water and the surficial aquifer with tritium (3H). The
 shallow ground water, between 4 and 10 feet (1.2 and
 3 m) deep, and the surficial aquifer that is approxi-
 mately 30 feet (9 m) below the surface both consist
 of non-potable water.
     Tritium contamination has also been detected
 in the potable water Local Aquifer which is 200 feet
 (62 m) deep. The 3H appears to be migrating down
 the exterior of the sampling well (HM-L) casing
 from the  surficial  aquifer  above.  Well HM-L  is
 located very close  to the SGZ and the well casing
 penetrates the  contaminated surficial aquifer. No
 contamination has been detected in a second Local
 Aquifer sampling well (HM-L2), located down gra-
 dient from HM-L. All 3H contamination is less than
 the concentration specified in the National Interim
 Primary Drinking Water Regulations (40CFR141).
 There is no indication from ground and surface water
 monitoring that any radioactivity is presently escaping
 from the test cavity.
     Following each explosive event, the near-offsite
 area was closely monitored by the U.S. Public Health
 Service (PHS). The radiological monitoring became
 the responsibility of EPA at its inception in 1970.
 The  EPA  radiological monitoring is a continuing
 responsibility. From 1964 to the present, neither the
EPA nor the PHS has detected  any contamination
 offsite resulting from the Tatum Dome experiments.

 Monitoring Results: Historical Summary

     After site cleanup activities in 1971-72 the
LTHMP was instituted.  In this program, all potable
aquifers, many individual wells, public water sup-
plies, and  some surface waters in the Tatum Salt
Dome area have been sampled and analyzed for

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                             Prentiss
                             •***_

                         Monticello
Brookhaven
                                                    Seminary


                                       Bassfield     A       f Moselle
                                                         Eatonyille

                                                                     Runnelstown
                                     Bunker  sumrall
                                     Hill
                             Columbia

                             ^
                             Cheraw
                                                               Purvis


                                                            Talowah
                                                                         Beaumont


                                                                   Brooklyn
 Tylertown-                I Pinebur   w

MISSISSIPPI                I      Baxterville
	7	\             ^Lumberton
LOUISIANA                I   /
                 Varnado ^   /
   — Major Highway

   (•) Test Site, SGZ
Figure 1. General site location.

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             All tritium contamination found
             within this circle with radius of
                   1400 feet (430m)
                    DRIBBLE SITE
                     BOUNDARY
      T
       W
       _0>
       1
       CM
       X
       2
       Q.
       Q.
       CO
      I
                         approx.  1 1/2 miles
            Baxterville
               M^_
         N
     SCALE IN FEET
1000    2000    3000   4000    5000
     _m
     500         1000
   SCALE IN METERS
                                                                        1238GR90NRD-2
Figure 2. Topographic map of the Tatum Dome Test Area showing the Surface Ground Zero and outline of
Salt Dome at 2,700 feet (830 m) below land surface.

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I
3
w
a
i
s
I
i
/Well HT-2
Surficlal Aquifer
                                       ^Anhydrite

                                   1160' ^    STA.1A   ps-1

                                          Salt Stock
                                      PS-1W

                                       PS-2W
                                                                 Test
                                                                 Cavity*
                                           Highly
                                           Radioactive
                                           Zone
                                     Recrystalized
                                     Melt Puddle
                    SANDSTONE
                               Ground Surface


                               Local Aquifer

                               Aquifer 1

                           iifT Aquifer 2A


                               Aquifer 2B

                               Aquifer 3A


                               Caprock Aquifer


                     •!•!•!•!•!•!•!•!•* Aquifer4


                     i|i|i|;|i!i!i!Ji|1 Aquifers
       *The test cavity contains fission and activation
        products from the detonations plus 10,770
        cubic yards of radioactive, contaminated soils
        and 1,305,000 gallons of contaminated fluids
        and water from surface cleanup.
                                                                                                                        1238GR90-3nnJ

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 tritium and for any detectable gamma-emitting ra-
 dioisotopes.
     A special study was conducted in  1977-78
 because of irregularities in tritium results in onsite
 samplings from a pond near SGZ (Half Moon Creek
 Overflow). To determine the source and extent of
 contamination, a grid design was used to locate 171
 shallow holes that were drilled into the surface ground
 water. From the tritium results of the samples collected
 from these holes, a set of LTHMP holes was selected
 and added to the LTHMP sampling design. Tritium
 levels in the surface ground water have shown large
 fluctuations due to local rainfall.  In general the
 concentrations continue to decrease.   Decreasing
 trends, representative of those sampling wells with
 the highest tritium concentrations, from the Local
 Aquifer (HM-L), the Surficial Aquifer (HM-S) and
 the surface ground water (HMH-1, HMH-2, HMH-
 5) are shown in Figure 4.
     Concern regarding possible health effects at-
 tributable to the two nuclear detonations conducted
 in the Tatum Salt Dome caused EPA to increase the
 scope of the radiological monitoring activities  in
 1990 to include the following:

   a.  Urine samples from nearby residents.
   b.  Vegetables and soil samples from local
       gardens.
   c.  Water samples from additional residen-
       tial wells.
   d.  Milk samples from goats and cows.
   e.  Atmospheric moisture monitoring.
   f.   Atmospheric paniculate monitoring.
   g.  Deer, turkey, catfish, and turtle from the
       vicinity of SGZ.
   h.  Soil, sediment, and vegetation sampling
       in the vicinity of SGZ.
   i.   Water samples for non-radiological analysis
       (volatile organics,  semi-volatile organics,
       pesticides, and heavy metals).
   j.   Cow tissue samples.
   k.  Goat tissue samples.
   1.   Five additional onsite shallow  ground-
       water monitoring holes.

     For 1990, in all of the offsite samples, including
human bioassay, no radioactive materials from the
Tatum  Dome Test Area were detected.  Tritium
contamination was detected in some water samples
taken close to SGZ but the concentrations met the
EPA criteria for drinking water. No other radioac-
tive material above background was detected in any
sample.  All tritium  contamination was detected
within  a 1,400-foot (430m) radius of SGZ.  The
analysis of water  samples taken in the vicinity of
SGZ for nonradioactive hazardous materials revealed
 very low level  concentrations of a few organic
 chemical contaminants of unknown origin. No health
 effects would be expected from the contaminants at
 the concentrations found.
      The 1990 study is described in the EPA report,
 "Onsite and Offsite Environmental Monitoring Re-
 port:  Radiation Monitoring Around Tatum Salt
 Dome, Lamar County, Mississippi, April 1990
 (Thome et al., 1990). All analytical data resulting
 from the LTHMP and other radiological monitoring
 programs are published annually in EPA's "Offsite
 Environmental Monitoring Report: Radiation Moni-
 toring Around United  States Nuclear Test
 Areas,...." These reports have been published each
 calendar year since the tests were conducted.

 Calendar Year 1991 Monitoring Results

      In April 1991, EMSL-LV conducted sampling
 on and around Tatum Salt Dome. In addition to the
 routine monitoring, a gamma-ray characterization of
 the Tatum Dome Test  Area was performed.  The
 locations of all sampling and gamma-ray measure-
 ment sites are shown in Figures 5 and 6.  Sampling
 also included three locations in Columbia, MS, not
 shown in Figure 6.  The sampling results are dis-
 cussed in the following sections.

 Water

     Much emphasis is placed on tritium analysis of
 ground-water samples. Following an underground
 nuclear test most of the radioactive materials that are
 created decay  away  very quickly. Most of those
 remaining are captured in the molten rock created by
 the explosion  and in the surrounding rock itself.
 Tritium, which is naturally occurring and is also a
 product of nuclear explosions, is a radioactive form
 of hydrogen.  It becomes incorporated in water
 molecules and moves with the ground-water flow.
 For this reason, tritium is used as an indicator of the
 migration of radioactive materials created from
 nuclear explosions.
     In April 1991, the HMH holes were sampled
 and then pumped dry. On the following day tritium
 samples were again  collected. Also, according to
 standard procedure, one HM well (Well HM-3) was
pumped steadily and five samples collected at one-
naif hour intervals. The other HM wells were pumped
 steadily and two samples collected at one-half hour
intervals. Two samples were taken on successive
days from Half  Moon Creek, Half Moon  Creek
Overflow, and the Pond West of GZ.   All other
locations were sampled  once.  Additional  water
 samples were collected at the request of  nine resi-
dents.

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                          Tritium in Water, Well HMH-1
                             Tatum Dome Test Area



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ouuuuu "
450000 -
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.

. 250000 -

i
200000 '
.

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50000 -

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               1978 1979 1980 19811982 1983 1984 1985 1986 1987 19881989 1990 1991 1992
                                         Year
 o
 o
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      250000
      200000 '
 O   150000 '
 a.

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 "•     100000 -
50000 -
                           Tritium in Water, Well HMH-2
                              Tatum Dome Test Area
                                               a..
                                                         -n—-a,.
                                                                   a—-a
             0 1978 1979 1980 19811982 1983 1984 1985 1986 1987 19881989 1990 1991  1992
Figure 4. Plots of tritium concentrations vs. time.

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                                Tritium in Water, Well HM-L

                                  Tatum Dome Test Area



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u
a.

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               0   1981 1982  1983  1984  1985 1986  1987  1988  1989  1990 1991  1992


                                             Year


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                                  Tritium in Water, Well HM-S

                                     Tatum Dome Test Area
                             "•n.
                                                                      '"a
                0   1981  1982  1983 1984 1985 1986   1987  1988  1989  1990 1991  1992


                                             Year

                                         (Depth = 30')
Figure 4. (Continued)

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                         Tritium in Water,  Well  HMH-5
                                   Tatum Dome Test Area





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           0  1978 1979 1980 1981 1982 19831984 19851986 1987 1988 1989 1990 1991 1992
                                             Year
                                                                               1041GR91-4A
Figure 4. (Continued)
Sample Analysis Procedures

     The procedures for analyzing samples collected
for this report were described by Johns et al. (EPA
1979) and are summarized in Appendix 3. These
include gamma spectral  analysis and radionuclide
analysis for strontium, tritium, and plutonium. The
EPA procedures are based on standard methodology
for given analytical procedures.  Two methods for
tritium analysis were performed—conventional and
electrolytic enrichment. The samples were initially
analyzed by the conventional method. If the tritium
result was less than 700 pCi/I, the sample was then
analyzed by the electrolytic enrichment method which
lowers the  Minimum Detectable Concentration
(MDC) from approximately 300 pCi/1 to 10 pCi/1. In
the data tables (Appendix 4), results obtained using
the conventional method are denoted by "3H" and
results obtained by electrolytic enrichment are de-
noted by "3H+". Sample results are corrected for the
background radioactivity in the laboratory. Occa-
sionally, negative results are obtained for extremely
low level samples  due to slight fluctuations in the
background or analytical variability.
Water Analysis Results

     No gamma-emitting radioactive materials were
detected.  The highest tritium concentration above
the MDC in water collected from the offsite area was
48 pCi/L. This is from natural sources and it is 0.24
percent of the National Interim Primary Drinking
Water Regulations (40CFR141) that places the
maximum level of tritium in drinking water to be
20,000 pCi/L. The water samples from Wells HMH-
1 and HMH-2 both had the highest tritium concen-
tration, 14,000 pCi/L, which is 70 percent of the
drinking water regulation. Wells HMH-1 andHMH-
2 are located near SGZ and the water is not accessible
to the public nor suitable for drinking due to its
brackishness. In addition to the tritium and gamma
spectroscopy analyses, water samples from locations
sampled for the first time were analyzed for '"Sr, 238Pu
and 239+24°pu.  All of the water sample results are
shown in Appendix 4. . Strontium-90, 238Pu, and
239+24opu were not detected at levels above the MDCs
of approximately 3 pCi/L, 0.05 pCi/L and 0.004 pCi/
L, respectively.

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     HMH-16
 Decontamiation
      Pad
                               HMH-6

                Water Lilies  xx —HMH-4
                                                                                   200
                                                           Location/water sample
                                                           Survey Location
                                                                                   N
  [WellHT-2C
'HT-2
                                                                                1238GR90NRD-5
Figure 5. Locations in the vicinity of surface ground zero sampled and monitored in 1991.

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3
(Q

3
0>
 o
 0)
 s

•o
 (O
 to
                Little Creek #1
              T.S. Saucier -
          Yancy Saucier -
      erman Gipson —

  Lower Little Creek
                               GIN Ray's Crawfish Pond
                                                     Hugh Gipson
                                                   r-Willie Surge
                                                   I  r~Joe Burge
                                                                                                        Hattiesburg
                                                                                                                •

                                                                                                               A  ©CD©®
Young s Dairy
     M
     u
Salt Dome Timber Co.
  Donald Beach
            A.C.
             Mills
           ujRoy Mills
B. Chambliss   R. King

       Anderson's Pond
     v)©(u)B.R. Anderson
 Dennis •
 Saucier
Hulon Lowe   Tatum Hunting
                 Club
Howard Smith
    Rita Moree
Sylvester Graham
       Lee L. Saul
                                                P.T. Lee
                                                 H. Anderson (
                                                   J.R. Nobles
                                                     G.W. Anderson©
                                                      Noble's Pond
                                                         Rita Smith
                                                                                                                           Purvis Well
                                                                                                                             * *13
                                                   Regina Anderson
                                              ,.,„   . .
                                              W. Daniels
                                                             Noble's Quail
                                                             House
                    Ray Daniels

                    Daniel's Well #2
        • Location/water sample
        0 Vegetation
        I) Soil          Goat
        u) Urine
        5) Milk
        * Non-Rad Water Sample
        A Atmospheric Tritium
                                                                                                      Lumberton
                                                                                                      i   W
                                                                                                          'u

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 Gamma-Ray Characterization Study

     This study was undertaken to inventory the
 amounts of surficial gamma-ray emitting radioactive
 materials and to determine the gamma-ray exposure
 rates on and around the Tatum Dome Test Area.
 Field measurements and  soil core sampling were
 conducted at eight sites on the Tatum Dome Test
 Area and four locations in the surrounding areas.
 The locations of the eight sites located near SGZ are
 shown in Figure 5. The remaining four sites are the
 B.R. Anderson residence near the Tatum Dome Test
 Area, Purvis Elementary School lawn, Purvis High
 School lawn and the Hattiesburg Fire Station #4 dirt
 lot.
     Gamma-ray spectra were collected in the field
 with a high-purity germanium detector (HpGe) and
 a desktop multi-channel analyzer. Power was sup-
 plied to the electronics by aportable gasoline-powered
 generator. The spectra were later interpreted by the
 methods described in Beck et al. (1972) and Heifer
 and Miller (1988). During the data collection time,
 pressurized ion chamber measurements were made
 around the individual sites and at the exact location
 of the HpGe detector to determine the overall exposure
 rates.
     In addition, soil core samples were taken from
 the sites to determine the distribution of radionuclides
 with depth. The samples were separated into depth
 intervals of 0-2.5 cm, 2.5-5.0 cm, and 5.0-15.0 cm
 and packaged for shipment to the EMSL-LV labora-
 tory, where they were prepared and analyzed.

 Gamma-Hay Characterization Results

     Appendix 5 lists the (one meter above ground)
dose rates measured in this study.  Under the head-
ings of "Total" and "PIC" are listed the sum of all
 nuclide and cosmic-ray contributions, and the pres-
 surized ion chamber readings at the same locations
 for comparison. Under the heading of "Other PIC
 Readings" are given the readings taken in the vicinity
 of each site.  In addition to the pressurized  ion
 chamber readings listed, the following locations
 were surveyed:  south bank of Half Moon Creek
 Overflow (5.5 u.R/hr), 20 m southeast of the surface
 ground zero (SGZ) monument (5.9 |J-R/hr), 40 m
 southeast of SGZ monument (5.7 ^iR/hr), 120 m
 southeast of SGZ monument on access road (7.0 jiR/
 hr), near Well HMH-11 approximately 40 m south-
 east of SGZ monument (6.1 uJR/hr), and inside
 REECo Pit near sampling location B (6.4 |iR/hr).
     The gamma-ray contribution sums and  the
 pressurized ion chamber  readings at all surveyed
 locations are in good agreement. In most cases the
 summed value is slightly  less than the pressurized
 ion chamber value probably due to attenuation of
 radiation by surrounding trees (Miller et al. 1990).
     Appendix 6 lists the 137Cs inventories calcu-
 lated for each site surveyed with the germanium
 detector.  The table shows the depth distribution
 parameter expressed as 3/p (Miller and Heifer 1985),
 137Cs activity per unit area, and the MDC. No other
 manmade radionuclides were detected. The 137Cs
 inventories at all onsite locations are much lower
 than those at offsite locations where the surveys were
 taken on lawns. This is expected because dense grass
 cover is known to strongly retain  deposited global
 fallout (Beck  1979), and the onsite locations were
 generally bare or partially covered. Also, all of the
 onsite surveys were made at locations where covering
 material was put down in remedial clean-up opera-
 tions. The presence of sand or gravel and the lack of
humus causes  a reduction of 137Cs retention and
promotes a deeper dispersion of the cesium that
remains, resulting in the low values of 3/p .
                                              11

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                                       CONCLUSION
     Njo radioactive materials from the Tatum Dome
Test Area were detected in any of the offsite water
samples. Onsite, tritium was the only radioactive
contaminant detected.  The tritium contamination
was found in brackish water collected from shallow
wells located near SGZ. Although this water is not
available to the public nor fit for human consumption
because of its brackishness, the tritium concentra-
tions are well below those defined in the EPA Na-
tional Interim Primary Drinking Water Regulations
(40CFR141).
     The gamma-ray characterization study showed
good agreement between the exposure rates derived
from in-situ gamma-ray spectrometry and those
measured with a pressurized ion chamber in all of the
locations surveyed. Variabilities of flux contributed
from radionuclides in the soil were small, with the
exception of 137Cs fallout, which was lower than
expected on all onsite locations. The 137Cs inventories
on cultivated lawns were the highest measured in this
study, but were within the range observed at other
locations with similar annual precipitation. Vertical
distributions of 137Cs in soil cores were found to be
extended, likely because of the large amount of
precipitation and the characteristics of the soil used
as backfill during cleanup and  decommission
operations. No other manmade gamma-emitting
nuclides were detected in laboratory analyses of soils
or in spectra collected at any locations. A comparison
of the  open-field pressurized ion chamber
measurements  in this study showed no significant
difference in gamma-ray flux at onsite and offsite
locations.
                                              12

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                                       REFERENCES
 1.   A Guide for Environmental Radiological Sur-
 veillance at U.S. Dept. of Energy Installations, July
 1981,  Office of Operational Safety Report,  U.S.
 DOE(DOE/EP-0023).

 2.   Beck, H.  L.   1979.   The natural  radiation
 background of Utah - Preliminary report on radio-
 nuclides in soils in populated areas. New York: U.S.
 Department of  Energy, Environmental Measure-
 ments Laboratory; EML-362.

 3.    Beck, H. L., J., De Campo, C. V., Gogolak.
 1972. In Situ Ge(Li) and Nal(Tl) gamma-ray spec-
 trometry.  New York:  U.S. Department of energy,
 Environmental Measurements Laboratory; HASL-
 258.

 4.    Federal Register, Vol. 41, title 40, Part  141,
 July 9, 1976, National Interim Primary Drinking
 Water Regulations.

 5.    Heifer, I. K., and K. M., Miller.  1988. Cali-
 bration factors for Ge detectors used for field spec-
trometry. Health Physics 55:15-29.

 6.    Johns, F. 1979. Radiochemical and Analytical
Procedures for Analysis of Environmental Samples.
 U.S. EPA, (EMSL-LV-0539-17-1979).
 7.   Lowder, W. M. and H. L., Beck. 1966. Cos-
 mic-ray ionization in the lower atmosphere.   J.
 Geophys.  Research 71:4661-4668.

 8.   Miller, K. M. and I. K., Heifer.  1985.  In situ
 measurements of 137Cs inventory in natural terrain.
 In: Proceedings of the Health Physics Society mid-
 year topical symposium; (6-10 January); Colorado
 Springs, CO: Central Rocky Mountain chapter of the
 Health Physics society; 1985:243-251.

 9.   Miller, K. M., J. L., Kuiper, and I. K., Heifer.
 1990.137Cs fallout depth distributions in forest ver-
 sus field sites: implications for external gamma dose
rates. J. Environ. Radioactivity  12:23-47.

 10.  Shleien, B. and M. Terpilak. 1984. The Health
Physics and Radiological Health Handbook. Nucleon
Lectern Associates.

 11.  Thome", D. J., C. F., Fontana, and C. F., Costa.
 1990. Onsite and offsite environmental monitoring
report: radiation monitoring around Tatum Salt Dome,
Lamar county, Mississippi. Las Vegas, NV:  U.S.
Environmental Protection  Agency, Environmental
Monitoring systems Laboratory; EPA/600/4-91/005.
                                              13

-------
                                        Appendix 1
Abbreviations

cm        centimeter = 1/100 meter = 0.39 inch
DOE      U.S. Department of Energy            24IAm
EMSL-LV  Environmental Monitoring Systems     3H
            Laboratory - Las Vegas              3H+
EPA       U.S. Environmental Protection Agency   ^Co
FDA      U.S. Food and Drug Administration     137Cs
HpGe      High purity germanium detector        ^Sr
keV       kilo electron volts = thousand electron   238Pu
            VOltS                               239+240^
kT        kiloton (TNT equivalent)
LTHMP    Long-Term Hydrological Monitoring
            Program                           HMH-1
L          liter                                thru 16
m         meter                               HM-L,
MDC      minimum detectable concentration      HM-L2
MeV      mega electron volts = million electron   HM-S
            volts
mL        milliliter = one thousandth of a liter     HM-1
NIST      National Institute of Science and
            Technology                         HM-2a
ppb        parts per billion
pCi/L      picocuries per liter = 10~12 curies per     HM-2b
            liter = 1/1,000,000,000,000 curies
            per liter                            HM-3
pCi/g      picocuries per gram = 10'12 curies per
            gram                               HT-2c, 4,5
PHS       U.S. Public Health Service
SGZ       surface ground zero
Americium-241
tritium
enriched tritium
cobalt-60
cesium-137
strontium-90
plutonium-238
plutonium-239 andplutonium-240 (in-
 dividual isotope not distinguished in
 analysis)
Hydrological Monitoring Hole

Hydrological Monitoring Well - Local
 Aquifer
Hydrological Monitoring Well -
 Surficial Aquifer
Hydrological Monitoring Well -
 Aquifer 1
Hydrological Monitoring Well -
 Aquifer 2a
Hydrological Monitoring Well -
 Aquifer 2b
Hydrological Monitoring Well -
 Aquifer 3
Hydrological Test Hole
                                             14

-------
                                         Appendix 2
                                     Glossary of Terms
 Background Radiation

     The radiation in man's natural environment,
 including cosmic rays and radiation from natural-
 occurring radioactive elements, both outside and
 inside the bodies of humans and animals. It is also
 called natural radiation. The usually quoted average
 individual exposure from background radiation is
 125 millirem per year in mid-latitudes at sea level
 (Shleien and Terpilak 1984).

 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 ap-
 proximately the rate of decay of 1 gram of radium;
 named for Marie and Pierre  Curie, who discovered
 radium in 1898.

 Isotope

     One of two or more  atoms with  the same
 number of protons, but different numbers of neutrons
 in their nuclei. Thus 12C, 13C, and I4C are isotopes of
 the element  carbon, the numbers denoting the ap-
 proximate atomic weights. Isotopes have very nearly
 the same chemical properties,  but often different
 physical properties (for example 12C and 13C are
 stable, I4C is radioactive).

 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

     All areas exclusive of the Tatum Dome Test
 Area.

 Onsite

     In this report refers to the area within the Tatum
 Dome Test Area.

 Shallow ground water

     Water found near the soil surface, caused by
 rain water saturation of the soil.  This shallow ground
 water is not an aquifer.

 Surficial Aquifer

     The ground-water layer located closest to the
 surface, generally at a depth of approximately 30 feet
 at SGZ.

 Tritium

     A radioactive isotope of hydrogen that decays
by beta emission. Its half-life is about  12.5 years.

 Type I Error

     The statistical error of accepting the presence
of radioactivity when none is present.

 Type II Error
                                              15

-------
 APPENDIX 3
 SUMMARY OF ANALYTICAL PROCEDURES
 TYPE OF
 ANALYSIS
  ANALYTICAL
   EQUIPMENT
  COUNTING
 PERIOD (MIN)
    ANALYTICAL
   PROCEDURES
    SAMPLE
      SIZE
    APPROXIMATE
  DETECTION LIMIT*
 IG or Ge(Li)
 Gamma
 Spectrometryb
IG or GE(Li)
detector calibrated
at 0.5 keV/channel
(0.04 to 2 MeV
range) individual
detector efficiencies
ranging from 15%
to 35%.
Individual air
filters, 30 min; 100
min for milk, water,
sus-pended solids.
Radionuclide concen-
tration quantified from
gamma spectral data
by on-line computer
program. Radionu-
clides in air filter com-
posite samples are
identified only.
3.5 L for liquids
and vegetables.
Generally 5 pCi/L for
most common fallout
radionuclides in routine
milk and water samples
in a simple spectrum.
              Low background
              thin-window, gas-
              flow, proportional
              counter.
                           50         Chemical separation by
                                      ion exchange. Separated
                                      sample counted succes-
                                      sively; activity calculated
                                      by simul-taneous solution
                                      of equations.
                                         LOLformilkor
                                         water; 0.1 to 1 kg
                                         for tissue.
                                          2pCi/L
 3H
Automatic liquid
scintillation counter
with output printer.
      300         Sample prepared by
                  distillation.
                       4 ml for water; 10
                       ml for urine; 50 g
                       for tissue.
                   300to700pCi/L
3H+
(Enrichment)
Automatic liquid
scintillation counter
with output printer.
      300         Sample concentrated by
                  electrolysis followed by
                  distillation.
                       250 ml for water.     10 pCi/L
 238,239+240pu   /^ha spectrometer
              with silicon surface
              barrier detectors
              operated in vacuum
              chambers.
                       1000 to 4000
                 Water sample or acid-
                 digested filter or tissue
                 samples separated by ion
                 exchange, electroplated
                 on
                 stainless steel
                 planchet.
                       1.0L for water; 0.1
                       to1 kg for tissue.
                   In water samples
                   0.08 pCi/L for ^Pu, and
                   0.05 pCi/L for 239*240Pu.
                   For tissue samples, 0.05
                   pCi per total sample for all
                   isotopes.
   The detection limit is defined as the smallest amount of radioactivity that can be reliably detected, i.e., probability of Type I and
   Type II error at 5% each.
   Gamma spectrometry using either an intrinsic germanium (IG), or lithium-drifted germanium diode (Ge(Li)) detector.
                                                          16

-------
 APPENDIX 4
 RESULTS FOR WATER SAMPLES COLLECTED IN APRIL, 1991
  SAMPLE
 LOCATION
COLLECTION
 DATE 1991
                                                         CONCENTRATION ± 2 S.D. IN pCI/L
                                                  (MINIMUM DETECTABLE CONCENTRATION [MDC])
                              "°Sr
2MPu
Anderson, Billy Ray            04/22


 Anderson Pond               04/22


Anderson, Regina             04/22


Anderson, Robert Harvey        04/22


Anderson, Robert Lowell        04/22

                           04/22


Burge, Joe                  04/22


Chambliss, B.                04/23


Daniels, Webster, Jr.           04/22


Daniels - Well #2              04/22
Half Moon Creek




Half Moon Creek Overflow




Hudson Quail House


Jr. Green Creek

Kelly Gertrude


King, Rhonda
   04/21

   04/22


   04/21

   04/22


   04/23


   04/23

   04/22


   04/22
                         Baxterville, MS

                             19±5*
                              (7.7)

                             13 ±6*
                              (9.8)

                             18±6*
                              (10)

                             16 ±5*
                              (7.4)

                             14+5*
                              (7.5)
                             26 ±6*
                              (9.9)

                             18 ±7*
                              (11)

                             -4 ±5.5
                              (9.1)

                             14±6*
                              (10)

                             24 ±5*
                              (7.1)
           19 ±5*
            (8.3)
           31 ±7*
             (10)

           120 ±7*
            (8.9)
           280 ±8*
             (10)

           48 ±8*
             (12)

Not Sampled - Could not locate sampling point

          -3.6 ±4.4
            (7.3)

           20 ±6*
            (10)
                                                                                                  (Continued)
                                                    17

-------
APPENDIX 4 Continued
RESULTS FOR WATER
SAMPLES COLLECTED IN APRIL, 1991
SAMPLE COLLECTION
LOCATION DATE 1991

Lee.P.T.
i
Little Creek #1
Lowe, M.
Lower Little Creek #2
Mills, A. C.
Mills, Roy
Nobles Pond
Noble, W.H., Jr.
Pond West of GZ
Ready, R. C.
REECo Pit Drainage-A
REECo Pit Drainage-B
REECo Pit Drainage-C
Salt Dome Hunting Club
Salt Dome Timber Co.
Saucier, Dennis

04/22
04/23
04/23
04/23
04/22
04/22
04/22
04/22
04/21
04/22
04/22
04/24
04/24
04/24
04/24
04/22
04/22
CONCENTRATION ± 2 S.D. IN pCI/L
(MINIMUM DETECTABLE CONCENTRATION [MDC])
3H 3H+ MSr ""Pu *wMopu
Baxterville,MS(Cont.)
44±6*
(9.1)
21 ±7*
(12)
Not sampled - On City Water
20 ±6*
(9.8)
0.50 ±4.6
(7.5)
20 ±5*
(7.3)
21 ±7*
(11)
36 ±7*
(11)
8.9 ±5.8
(9.4)
9.9 ±7.6
(12)
37 ±5*
(7.4)
20 ±6*
(9.8)
240 ±11*
(15)
290+8*
(10)
33 ±8*
(13)
26 ±6*
(9.4)
40 ±6*
(9.9)
                                                 (Continued)
18

-------
APPENDIX 4 Continued
RESULTS FOR WATER
SAMPLES

COLLECTED IN APRIL, 1991
CONCENTRATION ± 2 S.D. IN pCI/L
(MINIMUM DETECTABLE CONCENTRATION [MDC])
SAMPLE COLLECTION
LOCATION DATE 1991 3H 3H+ *>Sr ""Pu 2~»s«pu

Saucier, Talmadge S.
Saucier, Wilma & Yancy
Smith, Rita
Well Ascot 2
Well City
Well E-7
Well HM-1
Well HM-2A
Well HM-2B
Well HM-3
Well HM-L

04/23
04/23
04/22
04/23
04/23
04/23
04/22
04/22
04/22
04/22
04/22
04/22
04/22
04/22
04/22
04/22
04/22
04/22
04/22
04/22
Baxterville, MS(Cont.)
28 ±6*
(9.2)
1.1 ±6.7
(11)
Not Sampled - No One Home
Not Sampled - No Access
33 ±6*
(9.7)
8.5 ±6
(9.7)
1.9 ±5.4
(8.9)
0 + 5
(8.3)
-2.9 ±5.2
(8.6)
-2.8 ±5.7
(9.4)
-0.63 ±6.67
(11)
-1.2 + 5
(8.3)
-0.1 9 ±5.93
(9.8)
-4.1 ±5.4
(8-9)
2±5
(8.1)
-0.19 ±6.18
(10)
-2.5 ±7
(12)
1300 ±280*
(450)
890 ±280*
(450)
850 ±13*
(12)
                                                 (Continued)
19

-------
APPENDIX 4 Continued
RESULTS FOR WATER SAMPLES COLLECTED IN APRIL, 1991
 SAMPLE
LOCATION
COLLECTION
 DATE 1991      >H
                                               CONCENTRATION ± 2 S.D. IN pCI/L
                                         (MINIMUM DETECTABLE CONCENTRATION [MDC])
"°Sr
                                     Baxterville,MS(Cont.)
Well HM-L2

i

Well HM-S





Well HMH-1



Well HMH-2



Well HMH-3



Well HMH4



Well HMH-5



WellHMH-6



Well HMH-7

Well HMH-8



04/22

04/22

04/21

04/23

04/23

04/21

04/22

04/21

04/22

04/21

04/22

04/21

04/22

04/21

04/22

04/21

04/22

04/21
04/22
04/21

04/22





7500 ±340*
(450)
7600 ±340*
(450)
7400 ±340*
(450)
5000 ±320*
(450)
14,000 ±390*
(450)
7200+340*
(450)
14,000 ±400*
(450)

_






2200 ±290*
(450)
2700 ±300*
(450)




0.91 ±5.76
(9.5)
-3.4 ±7.2
(12)














41 ±7*
(11)
44 ±5*
(8.2)
18±6*
(10)
14 + 6*
(8.8)




210 ±8*
(10)
170 ±7*
(8.7)
Not Sampled - Under Water






16 ±6*
(10)
22 ±5*
(8)
                                            20

-------
APPENDIX
4 Continued
RESULTS FOR WATER SAMPLES

COLLECTED IN APRIL, 1991


CONCENTRATION ± 2 S.D. IN pCI/L
(MINIMUM DETECTABLE CONCENTRATION [MDC])
SAMPLE
LOCATION

Well HMH-9
Well HMH-10
WellHMH-11
WellHMH-12
Well HMH-13
Well HMH-14
Well HMH-15
WellHMH-16
Well HT-2C
Well HT-4
Well HT-5
COLLECTION
DATE 1991 3H 3H+ "Sr

04/21
04/22
04/21
04/22
04/21
04/22
04/21
04/22
04/21
04/22
04/21
04/22
04/21
04/22
04/21
04/22
04/23
04/23
04/23
Baxterville,MS,(Cont.)
130 ±8*
(11)
150 ±7*
(9.4)
91 ±8*
(11)
35 ±7*
(10)
22 ±5*
(7.5)
21 ±7*
(11)
16 ±6*
(10)
17 ±5*
(8.2)
18±6*
(10)
19±7*
(11)
16 ±6*
(8.9)
11 ±6*
(10)
18 ±6*
(10)
8.9 ±5*
(8.2)
31 ±6*
(8.8)
38 ±6*
(8.6)
18 ±7*
(12)
7.6 ±6
(9.8)
4.216.5
(11)
2MB it 23ft+240B|]












                                                    (Continued)
21

-------
APPENDIX 4 Continued
RESULTS FOR WATER
SAMPLES COLLECTED
IN APRIL, 1991


CONCENTRATION ± 2 S.D. IN pCI/L
(MINIMUM DETECTABLE CONCENTRATION [MDC])
SAMPLE COLLECTION
LOCATION DATE 1991 3H

Dennis, Buddy
Dennis, Marvin
Well 64B City

Anderson, G. W.
Anderson, Lee L.
Beach, Donald
Bond, Bradley K.
Cox, Eddie
Daniels, Ray
Gil Ray's Crawfish Pond
Gipson, Herman
Graham, Sylvester
Moree, Rita - House Well
Powell, Shannon
Rushing, Debra
Saul, Lee L.

04/23
04/23
04/23

04/22
04/22
04/22
04/22
04/24
04/22
04/23
04/22
04/23
04/23
04/22
04/24
04/23
3H+
Columbia, MS
14 ±4*
(6.7)
26 ±6*
(8.7)
17 ±6*
(10)
Lumberton, MS
27 ±5*
(8.2)
26 ±7*
(11)

28 ±6*
(9.3)
36 ±7*
(11)
27 ±5*
(7.7)
13 ±5*
(8.6)
21 ±5*
(7.3)
-2.616.7
(11)
4.8 ±4.5
(7.4)
18 ±6*
(9.5)
34 ±7*
(10)
-1.3 ±6.5
(11)
•°Sr ^Pu

0.21 ±0.63 0.0048± 0.0096
(1.4)
0.36 ±0.61 0± 0.0094
(1.4)



0.27 ±0.60 -0.0027± 0.0121
(1.4)
No sample - residents moved,
-0.088 ± 0.71 3 -0.0039± 0.0079
(1.5)
0.077 ±0.573 0± 0.0066
(1.3)




0.51 ±0.60 0± 0.0065
(1-3)
0.93 ±0.63 0.01 6 ±0.032
(1.4)

231*240pu

0± 0.0068
0± 0.0094



0.0054 ±0.01 08
well down
-0.0020 ±0.0039
0± 0.0066




0.0068 ±0.01 21
-0.0080 ±0.01 60

                                                   (Continued)
22

-------
APPENDIX 4 Continued
RESULTS FOR WATER SAMPLES COLLECTED IN APRIL, 1991
SAMPLE COLLECTION
LOCATION DATE 1991

Smith, Howard 04/23
Smith, Howard - Pond 04/23
Well 2 City 04/23

Burge, Willie Ray & Graco 04/22
City Supply 04/22
Gil, Ray -House Well 04/22
CONCENTRATION ± 2 S.D. IN pCI/L
(MINIMUM DETECTABLE CONCENTRATION [MDC]}
3H ^ .«* ^ _pu
Lumberton, MS, (Cont.)
0.073 ±4.598
(7-6)
18 ±5* 0.44 ±0.59 0 ±0.011 0.0075 ±0.0151
(7.7) (1.4)
4.7 ±5.9
(9.6)
Purvis, MS
15 ±5*
(7.7)
6.4+5.8
(9.4)
2.6+6.2
(10)
* Concentration is greater than the minimum detectable concentration (MDC). Where gamma spectral analysis was performed, only
 collection dates are shown.
                                                       23

-------
APPENDIX 5
EXPOSURE RATE INVENTORIES AT ALL SURVEY LOCATIONS (Other pic readings taken near the location
are also given.) A discussion of uncertainties is given in the following section.
COSMIC WK
ONSITE
(1 ) Surface Ground Zero (12m
northwest of monument)
(2) Postshot No. 1 Slush Pit
(3) WellHT-2
(4) WellHT-2M
(5) Decontamination Pad (20 m
north of beaver pond)
(6) REECoPitA
(7) REECoPitB
(8) REECoPitC
OFFsrre
(9) B. R. Anderson Residence
(lawn 30 m west of house)
(1 0) Purvis Elementary School
(lawn 100 m southwest of
school)
(11) Purvis High School
(lawn 150 m north of school)
(1 2) Hattiesburg Fire Station
#4 Lot
(13) Hattiesburg Hotel Room


3.6
3.6
3.6
3.6

3.6
3.6
3.6
3.6


3.7


3.7

3.7

3.6
3.6


0.2
0.4
0.3
0.6

0.2
0.4
0.5
0.4


0.5


0.3

0.4

0.2
1.0
Th


0.9
1.6
1.2
1.5

0.9
1.5
1.7
1.5


1.3


0.9

1.1

0.8
1.8
U


1.1
1.0
0.8
1.1

0.8
1.0
1.1
0.9


1.4


0.9

0.9

0.9
1.6
EXPOSURE RATE friR/HR)
Rn "Be 1"Cs TOTAL


0.1
0.1
0.1
0.1

0.1
0.1
0.1
0.1


0.1


0.1

0.1

0.1
—


„
0.01
0.01
0.01

0.01
._
0.01
0.01


0.01


0.01

0.01

0.01
—


0.02*
0.02
0.03
0.06

0.01*
0.03
0.01
0.02


0.1


0.2

0.1

0.1*
™


5.9
6.7
6.0
7.0

5.6
6.6
7.0
6.5


7.1


6.1

6.3

5.7
8.0
PIC


6.0
7.0
6.9
7.2

7.0
6.5
6.7
6.7


8.0


6.7

6.4

6.4
6.6
OTHER
PIC READING


6.2,
7.2,
6.4,
6.8,

7.1,
7.2,
6.6,
7.0,


7.0,


6.8,

6.3,

6.0,



5.9, 6.1
6.5, 6.1
6.8, 6.4
7.5, 6.8

6.0, 6.4
7.3, 6.8
6.0, 6.4
6.6, 6.9


6.7, 7.2


6.4, 6.8

6.7, 6.5

6.5, 6.3
*—•
'Assuming <*/p = 0.5 (no cores taken)
24

-------
APPENDIX 6
SOIL SAMPLE STUDY
                                                                      IN-SITU SPECTROMETRY
                                                               «/p"              (mCi/km2)            MDC
ONSITE

 (1)  Surface Ground Zero (12m
      northwest of monument)                                   0.05a             10.611.5               (5.2)
 (2)  Post Shot No. 1. Slush Pit                                   0.081b             7.311.0               (5.4)
     (15m east of monument)
 (3)  WellHT-2                                                0.13               7.811.7               (3.8)
 (4)  WellHT-2M                                              0.060             25.213.5               (7.7)
 (5)  Decontamination Pad                                       0.05a              6.512.1                (4.1)
 (6)  REECoPitA                                             0.17               7.911.7               (3.7)
 (7)  REECoPitB                                             0.10               4.710.2               (4.7)
 (8)  REECoPitC                                             0.032°            15.514.2              (10.7)

OFFSITE

 (9)  B.R. Anderson Residence                                   0.065             42.613.7               (7.3)
(10)  Purvis Elementary School                                   0.068             89.113.5               (7.8)
(11)  Purvis High School                                         0.052             56.814.6               (8.4)
(12)  Hattiesburg Fire Station #4 Lot                                0.05a              4.412.2               (5.8)

'Estimated value.
''Derived from result of combined six core samples.
c Derived from result of one core sample (all others derived from combined three core samples).
"x/p  = x Corresponds to surficial deposition, <*/p = 0 corresponds to uniform distribution
                                                      25

-------