NV0 - 162 - 25 

* 

,.., ,. I, 

1: _ ) . I I z 

ENVIRONMENTAL RADIOACTIVITY~fq~p 

AT THE NEVADA TEST SITE 

JULY 1965 THROUGH JUNE 1966 

RADIOLOGICAL SCIENCES DEPARTMENT 

SITE FACILITIES DIVISION 

REYNOLDS ELECTRICAL 8. ENGINEERING CO., INC. 
ENVIRONMENTAL RADIOACTIVITY 

AT THE 

NEVADA TEST SITE 

JULY 1965 THROUGH JUNE 1966 

The staff of 

The Environmental Surveillance 

Group 

RADIOLOGICAL SCIENCES DEPARTMENT 

SITE FACILITIES DIVISION 

Work performed Under Contract AT(29-2)-162 

between 

The United States Atomic Energy Commission 

and 

Reynolds Electrical & Engineering Co. , Inc. 

Mercury, Nevada 

November 1966 
LEGAL NOTICE 

This report was prepared as an account of Government sponsored work. 

Neither the United States, nor the Commission, nor any person acting 

on behalf of the Commission: 

A. Makes any warranty or representation, expressed or implied, 

with respect to the accuracy, completeness, or usefulness of 

the information contained in this report, or that the use of any 

information, apparatus, method, or process disclosed in this 

report may not infringe privately owned rights; or 

B, Assumes any liabilities with respect to the use cf, or for damages resulting from the use of any information, apparatus, 

method, or process disclosed in this report. 

As used in the above, “person acting on behalf of the Commission” 

includes any employee or contractor of the Commission, or employee 

of such contractor, to the extent that such employee or contractor 

of the Commission, or employee of such contractor prepares, disseminates, or provides access to, any information pursuant to his 

employment or contract with the Commission, or his employment 

with such contractor. 
ACKNOWLEDGEMENTS 

The Technical Reports Coordination Group of the Radiological Engineering 

Section edited the text. Special assistance was provided during the preparation and final review of this report by the Technical Advisory ‘Committee of the Radiological Sciences Department, 

ii 
TABLEOFCONTENTS 

Section 

Legal Notice 

Acknowledgements 

List of Figures 

List of Tables 

Introduction 

1 Air Sampling 

2 Water Sampling 

3 Soil and Vegetation Sampling 

Appendix 

A Statistical Treatment of Data 

Page 

i 

ii 

iv 

V 

1 

2 

5 

9 

38 

. . . 

111 
LIST OF FIGURES 

Figure Page 

1 

2 

3 

4 

5 

6 

7 

8 

9 

10 

11 

12 

13 

NTS Environmental Surveillance Air Sampling Locations 

Weekly Means and Ranges of Gross Beta Radioactivity 

from July 1964 through June 1966; Air Sampling 

Means and Ranges of Gross Beta Radioactivity from 

July 1965 through June 1966; Air Sampling 

Water Sampling Station Locations 

Means and Ranges of Gross Beta Radioactivity from 

February 1965 to June 1966; Industrial Water 

Descending Means of Twelve Sampling Locations; 

Industrial Water 

Percent Frequency Distribution of Gross Beta 

Radioactivity; Industrial Water 

Means and Ranges of Gross Beta Radioactivity in 

Potable Water Samples from February 1965 through 

June 1966 

Percent Frequency Distribution from Gross Beta 

Radioactivity in Potable Water 

Soil and Vegetation Sample Stations 22 

Means and Extremes of Soil and Vegetation Samples 23 

Soil and Vegetation Radioactivity 24 

Soil and Vegetation Radioactivity 25 

13 

14 

15 

16 

17 

18 

19 

20 

21 

iv 
LIST OF TABLES 

Table 

1 Environmental Surveillance Air Sampling Station Locations 

2 Sampling Period Means and Ranges of Gross Beta Radioactivity in Environmental Air Samples from NTS. July 

1964 through June 1966 

2A Sampling Period Means and Ranges of Gross Beta Radioactivity in Environmental Potable Water Samples from 

NTS. February 1965 through June 1966 

3 Means and Ranges of Gross Beta Radioactivity in NTS 

Environmental Air Sampling Station Locations from July 

1965 through June 1966 

4 Water Sampling Station Locations 

5A Sample Period Means and Ranges of Gross Beta Radioactivity in Monthly Environmental Industrial Water 

Samples from NTS. February 1965 through June 1966 

5B Descending Means of Gross Beta Radioactivity in Monthly 

Environmental Industrial Water Samples from NTS. 

July 1965 through June 1966 

5c Means a.nd Ranges of Detectable Alpha and Beta 

Activity in Eight Miscellaneous Water Sample 

Locations for Fiscal Year July 1965 through June 1966. 

6 Gross Beta Activity of Soil and Vegetation Samples 

for Fiscal Year 1966. 

Page 

26 

27 

30 

32 

33 

34 

35 

36 

37 

V 
INTRODUCTION 

This report contains a summary of the data obtained concerning the radiological 

conditions in the environment of the Nevada Test Site (NTS), performed under 

contract to the AEC by the Radiological Sciences Department of the Reynolds 

Electrical & Engineering Co. , Inc. 

The Environmental Surveillance Branch performs routine radiation surveys 

using portable instruments in non-radiation zone areas of the Test Site such 

as living quarters, administrative buildings, and cafeterias. Surface swipes 

and samples of air and water are collected for laboratory analysis. Additionally, 

samples of water from waste ponds, sewage basins, reservoirs, springs, 

and wells are collected on a routine basis to determine normal levels of 

radioactivity or any changes of radioactivity. Air, soil, and vegetation 

samples are also routinely collected. at selected locations throughout NTS 

for the same purpose as the water samples. All environmental samples are 

analyzed routinely for gross alpha and beta radioactivity. Significant increases 

or changes in the radioactivity levels of these samples are reported to the 

appropriate field monitoring groups for investigation and remedial action 

where appropriate. All samples are documented by the Environmental 

Surveillance Branch for record purposes and for comparison with previous 

results to determine trend and correlation where feasible. 

This report presents the data derived from the sampling program for the 

period July 1965 through June 1966. 
SECTION 1 

AIR SAMPLING 

1: 1 Introduction 

The Environmental Surveillance Branch maintains low-volume, constantly-operating air samplers at 14 permanent locations (Figure 1 

and Table 1) placed to provide monitoring of the particulate airborne 

contamination within the Nevada Test Site (NTS) boundaries. 

1. 2 Description of Equipment 

The sampling equipment used consists of a positive displacement Gast 

pump that pulls air through a 4” (Whatman 41) filter paper which is 

mounted in a disposable plastic filter head. A dry gas meter is utilized to measure the total volume of displaced air over a period of 

seven days. The total volume ‘of air sampled during a regular seven 

day sampling period is approximately 1 x lo3 cubic meters (m3). The 

flow rate of air through the filter is maintained at approximately four 

cubic feet/minute. 

1. 3 Counting Procedures 

All collected air samples were held in storage for at least five days 

before counting. This time interval allows the naturally occuring 

radon and thoron daughters to decay to insignificant levels. Air samples were analyzed for gross alpha and beta using a Nuclear Chicago 

ULTRASCALER gas proportional system having an efficiency (the 

ratio of observed counts to known disintegrations) of 22% for alpha. 

and 51% for beta. Background counts for alpha and beta on this instrument were determined by counting for 100 minutes. The samples were 

counted for 20 minutes. A Baird Atomic SPECTROMETER was used 

in determining gross gamma activity. If the activity for gamma was 

such that the apparent 2acounting error was less than 50%, then the sample was transferred to a 400-channel gamma-spectrum analyzer to qualitatively determine tl-e contributing radionuclides. 

Sample activity results, reported by the Radiological Measurement Laboratory, were compared with an established “alert level”. The determination of the alert level is based on the maximum permissible concentrations 

of unknown radionuclides in air for a period of 168 hours, (MPCU)a as outlined in the National Bureau of Standards Handbook 69, page 94. The alert 

level for beta has been maintained at 1 x lo-l1 bCi/cc of air after a five day 

decay period and at 1 x lo-l4 pCi/cc for alpha activity. Though a sample 

may exceed this alert level, it does not necessarily mean that the actual 

MPC has been exceeded. Whenever a sample does approach or exceed this 

established guide, more intensive sampling and more involved analyses are 

performed to determine if the contamination is valid. 

- 2 
1. 4 Data Discussion 

The means and ranges of gross beta radioactivity in weekly collections of air 

samples from the 14 permanent locations from July 1965 through June 1966 

are tabulated in Table 2 and plotted in Figure 2, During this fiscal year (July 

1965 through June 1966) no sample activity value exceeded the “alert level” of 

1 x lo-l1 /Xi/cc in air . The highest value recorded for beta radioactivity 

occured in the air sample collected from Area 18 Camp 17 (Figure 1) for the 

first week in June, 1966. This value, 3.93 x lo-l2 hCi/cc, is below the established limit. Fluctuations for this fiscal year followed a trend of decrease 

in activity values during July through December which were periods of reduced 

testing operations and an obvious increase from March through June which . 

coincided with a period of intensive testing at both the Nuclear Reactor Development Station (NRDS) and NTS. During this latter period of intensive testing, 

some detonations occurred which released radioactivity to the atmosphere. 

Additions of contamination to the environment occured when tests were conducted with the nuclear reactors at NRDS. 

Figure 3 and Table 3 show the plotted means and ranges for each of the mean 

values of all 14 sampling locations averaged 1. 37 x lo-l3 pCi/cc. This value 

is lower than the mean value observed for all 

FI amples collected for the previous year which averaged 6.6 x lo-l3 pCi/cc. 

The highest observed, mean value for a sampling location was 2.19 x lo-l3 

pCi/cc at Area 18, Camp 17 and the lowest was 7.75 x lo-l4 /Xi/cc at 

Area 25, NRDS. The wide range of values encountered during this sampling 

period, as shown in Figure 3 and Table 3 (greater than a factor of loo), was 

the result of a single high or low value. These extreme values did not drastically effect the mean due to logarithmic transformation of the observed 

activity results. (The statistical treatment of data for this report is presented in Appendix A). 

Detectable alpha activity values for air during this period occurred infrequently and at isolated locations. Though 48% of the total number of air 

samples collected during this report period showed activity levels over background, a statistical summary of this data would not be meaningful because 

of the uncertainty associated with results uncorrected for self absorption 

and the low activity values which result in a high relative 2acounting error. 

Routine gamma counting of all environmental air filters was initiated in 

February 1966. The majority of air samples which were counted for gross 

gamma during part of this report period indicated levels less than background. Except for the sampling period ending the first week in June, when 

all stations.indicated the presence of short-lived gamma emitting radionuclide’s, 

all other isolated cases were associated with an individual test operation. 

Gamma spectrum and decay analyses of these samples in June indicated that 

their origin was from a nuclear detonation on the Chinese mainland on May 9, 

1966. In all cases, the presence of gamma emitting radionuclides, as determined qualitatively by spectrum analysis, did not pose a health hazard due to 

failure of identification in the succeeding week’s samples. 

3 
The observed mean of gross beta radioactivity for a total of 613 air samples 

collected this year was 1. 37 x lo-l3 pCi/cc. For the same sampling period 

during the previous year, it was 6.6 x lo-l3 p &cc and 1 x lo-l2 pCi/cc for 

the semi-annual period, January through June 1964. 2 

1.5 Summary 

These results indicate a gradual decrease in mean values since preceding 

periods. This can be attributed to a number of contributing variables: less 

intensive testing operations, fewer venting problems, refined air volume 

measurements, more careful laboratory preparation methods, and improved 

counting procedures. 

Results of environmental surveillance air sampling activity values obviously 

cannot be used in calculating exposure doses. They are instead used in the 

determination of trends, and emphasis is either sustained or shifted to other 

sample types whenever a significant increase in levels is noted. 

ILewis, Gary B. , Glora, Michael A. , and Aoki, Isamu, “Environmental 

Radioactivity at the Nevada Test Site, July 1965 through June 1966, ” NVO162-18, Radiological Sciences Department, Reynolds Electrical & Engineering 

co. , Inc. December 1965. 

2Glora, M. A, and Brown, B. L. “Environmental Surveillance, JanuaryJune 1965: A Semiannual Report. ” NVO-162-16. Reynolds Electrical & 

Engineering Co, , Inc. , Radiological Sciences Department. August 1964. 

4 
SECTION 2 

WATER SAMPLING 

2.1 Introduction 

Water samples were collected from selected waste ponds, reservoirs, 

sewage basins, natural springs, and potable water sources, such as 

cafeterias, swimming pools, etc., on a “grab sample” basis. 

2.2 Collection Methods 

Water samples were collected in one liter glass bottles on a weekly, 

monthly, and special basis depending upon the potential for radioactive 

contamination. The potable water samples were collected from taps at the 

point of consumption after allowing the water to run for a length of time. 

All industrial reservoir waters were collected near the inlet points of 

the reservoirs; while the natural spring waters were “grab” samples 

taken by dipping at the surface. 

2. 3 Sample Preparation 

All water samples were prepared for gross alpha, beta, gamma, and 

tritium analyses. A 15 ml aliquot was first taken from the original 

sample in a 5 dram plastic vial and submitted to the counting laboratory 

to be gamma scanned. A 1 ml sample was taken for tritium analysis 

which was performed using standard liquid scintillation counting techniques. The remainder of the one-liter sample was evaporated to 15 ml, 

transferred to a two-inch stainless steel planchet, and evaporated to 

dryness under infra-red lamps. A wetting agent was added during final 

evaporation to provide even distribution of the sample on the planchet. 

From the preparations laboratory, the samples were sent to the counting 

laboratory and counted for alpha and beta. 

2.4 Counting Procedures 

All routine environmental samples were analyzed for gross alpha and beta 

radioactivity by gas proportional counting. The water samples were analyzed 

by a Beckman WIDEBETA system equipped with an automatic sample 

changer. The efficiencies, i. e. , the ratio of observed counts to known 

disintegrations, on the WIDEBETA system, were 27% for alpha and 57% for 

beta. The average background count rate was 0.03 counts per minute for 

alpha and 1.8 counts per minute for beta. 

The tritium analyses were performed using a Packard Tri-Carb Liquid 

Scintillation Spectrometer with an efficiency of 18% and an average background of 16 counts per minute. 
2.5 Statistical Summary of Results for Water 

2.5.1 Industrial Water Samples 

Industrial water is used for construction and maintenance operations, 

such as watering roads, washing down equipment, drilling wells, and 

other interrelated activities. In an effort to adequately cover the 

Nevada Test Site, twelve sampling stations were selected at predetermined locations (Figure 4 and Table 4). All of the stations were 

sampled once a month. 

Table 5A and Figure 5 give the means and ranges for gross beta 

activity over a 17-month period. The means, for the period February 1965 to June 1966, ranged from 4.5 x lo-’ pCi/cc, recorded 

in September of 1965 to 2.04 x low8 /Xi/cc, recorded in August of 1965. 

The maximum value for the 17-month period was 1.14 x 10B7 pCi/cc 

which was recorded in August of 1965 at Area 25, CP Water Tower. 

The average mean for fiscal year 1966 was computed at 1.02 x 10m8 

pCi/cc which was higher than the mean for fiscal year 1965 which 

was 1.00 x 10Q8 ,uCi/cc. (Refer to footnote #I, page 2. ) The 1965 data 

prior to February 1965 is not presented here due to the fact that all 

of the water samples that were collected exceeded MPCw values 

because of small sample size. This invalidated the data for the 

beginning of fiscal year 1965, thus making it meaningless as far as 

actual comparison with the data collected in the latter’ half of fiscal 

year 1965, as well as with the 1966 data, is concerned. 

Table 5B and Figure 6 show the descending means of the 12 sampling 

locations. The values were quite low, with Area 3, Well A reservoir 

and Area 5, Well 5B reservoir representing the mid-points along the 

descending line. 

The percent frequency distribution of gross beta activity in the industrial 

water samples of NTS can be seen in Figure 7. The curve in this case 

is skewed to the right indicating the majority of the activity was in the 

lower ranges, well below (MPCU), levels. 

2. 5. ‘2 Potable Water Samples 

The statistical breakdown for potable water samples for fiscal year 

1966 was based on ten sampling locations (Table 4 and Figure 4), taken 

on a weekly basis. 

Table 2A and Figure 8 give the means and ranges for gross beta 

activity over a 17-month period covering the latter half of fiscal year 

1965, February 1965 to June 1965, and all of fiscal year 1966, July 1965 

to June 1966. The means ranged from 2.17 x lo-’ /-G/cc recorded February 20, 1966 to 5.13 x lob8 pCi/cc recorded April 24, 1966. The 

6 
maximum value for the 17-month period was 3.41 x low7 pCi/cc 

recorded April 24, 1966 at the Area 3, Cafeteria. The average mean 

for fiscal year 1966 was 6.29 x lo-’ pCi/cc as compared with the mean 

for fiscal year 1965 which was 5.6 x lo-’ @i/cc. The complete data 

presentation was not given for fiscal year 1,965 for the same reasons as 

were outlined in section 2.5.1. Even though larger than last year’s mean 

the average for potable water is still well below the (MPCU), levels. 

which is set at 1 x 10m7 pCi/cc and is based on the exposure guides 

recommended by the National Bureau of Standards, Handbook 69. 

j This holds, even though water samples from three locations in Areas 

18, 20, and 51 were above MPC, levels. 

Figure 9 indicates that the frequency distribution curve for gross beta 

activity in potable water samples at NTS is skewed to the right. This 

indicates that the majority of the activity values are well below (MPCU), 

levels. 

2.5. 3. Miscellaneous Water Samples 

There were eight miscellaneous water sampling locations for fiscal 

year June 1965 through July 1966. Each location has some unique characteristic that removes it from the industrial and potable water groups 

and because of this each location will be treated separately. 

The first two areas to be discussed are the Mercury swimming pool in 

Area 23 and the Groom Lake swimming pool in Area 51 (Table 4 and 

Figure 4). Both swimming pools are unique in that the water is constantly being filtered. The swimming pool in Mercury is open to atmospheric fallout at all times while the swimming pool at Groom Lake is 

enclosed; but dust from the outside can still be carried in and dispersedin the water. 

The next two locations which are related are Well J-12 and Well 3 

in Area 51. Both wells were sampled directly from the well stem and 

because of this represent totally closed systems. In other words, there 

is no chance of atmospheric contamination since both wells are completely closed with no openings between the well, water and the air. All 

of the other well samples, throughout the Site, were taken from associated 

reservoirs rather than the wells themselves. 

The third group of related sample locations are the permanent bodies 

of contaminated water located at the Control Point (Cl?) decontamination pad in Area 6 and the Upper and Lower Haines Lakes in Area 12. 

The waste pond at the CP area was constructed to contain liquid radioactive waste from the decontamination operations performed in the area. 

The Haines Lakes were established as reservoirs for industrial water 

when a water source was exposed during construction of tunnel U12e 

(E tunnel). This latter water source became contaminated during a test 

7 
in E tunnel in 1961 and has continued to discharge contaminated seepage 

water. Like the CP waste pond, these reservoirs are controlled radiation zones. Papoose Lake, in Area 51, is the only natural drainage basin 

on the Test Site which is continually sampled. Any contamination 

which shows up there is the result of air-borne surface material or 

atmospheric fall-out from past atmospheric detonations. 

Table 5C gives the geometric means and ranges for all eight locations 

based on samples collected once-a-month over a twelve-month sampling 

period. The table is broken down into location, number of samples, 

mean and range of alpha @Ci/cc), mean and range of beta (/Xi/cc). 
SECTION 3 

SOIL AND VEGETATION SAMPLING 

3.1 Introduction 

Soil and vegetation samples were collected at monthly intervals from 23 

sample locations. For a map of these locations see Figure 10. Routine 

collection of soil and vegetation samples was discontinued March 1, 1966 

for reasons discussed later. 

Methods and procedures followed in collecting, preparing, and counting 

these samples were similar to those used in prior years. The methods 

are also similar to the environmental surveillance programs followed at 

other atomic energy installations and the results are similar in that the 

Test Site experiences the same heterogeneity in soil and plant samples 

as reported from other installations. At NTS, routine sampling has been 

discontinued until improved procedures can be developed that will reduce 

the heterogeneity that has plagued this part of the program. This is discussed more fully in Section 3.6. 

3. 2 Sample Collection 

Soil and vegetation samples were collected at the same time and place. 

Vegetation samples were collected from the top portions of the dominant 

perennial shrubs found at each station. Vegetation samples were brought 

to the laboratory in size-12 Kraft paper bags closed at the top and secured 

by masking tape. 

Soil samples were taken from a 64-square inch area of “clear” ground to a 

depth of l/4 inch. The effect of this requirement of “clear” ground on the 

heterogeneity of soil samples is discussed in Section 3. 6. Soil samples 

were taken to the laboratory in sealed, one-quart ice cream cartons. 

3. 3 Sample Preparation 

Vegetation samples are logged in when received by the laboratory, surveyed 

with portable instruments, and weighed in. an aluminum pan to obtain the wet 

weight which is recorded. The samples are then dried for 24 hours at 190°F, 

cooled, reweighed, and the dry weight recorded. The dried sample is then 

pulverized in a Waring-type blender. The sample thus contains leaves, twigs, 

bark, flower parts, and fruit. All of the plant material collected by the 

monitor in the field becomes part of the pulverized sample from which a 

5-gram aliquot is weighed into a 5-dram plastic vial for gamma counting. 

A 25-gram aliquot of this pulverized sample is ashed in a muffle furnace. 

4 
The ashing process begins at 200°C and the muffle is gradually raised to 

600°C and held at this temperature until the sample has been in the muffle 

for 24 hours, of which about 20 hours have been at the 600’ temperature. 

The ashed sample is cooled in a desicator and a one-gram aliquot is 

weighed into a small beaker. Nitric acid is added to the beaker and the ash 

is leached for three hours. The leach is then filtered through a Whatman 

No. 42 filter paper using gravity flow. The filtrate is reduced in volume 

under a heat lamp and then transferred onto a standard planchet where it is 

slowly and carefully evaporated to dryness. The sample is then surveyed, 

placed in a petri dish for protection, logged out, and counted for gross 

alpha and beta. 

Soil samples are logged in, surveyed, and wet weighed obtained following 

the same procedures as for vegetation samples. The samples are then 

dried for 24 hours at 190°F, and after cooling the dry weight is made and 

recorded. The samples are pulverized with a mortar and pestle until a 

majority of the sample will pass through a 100 mesh screen. Five grams 

are weighed into a small beaker for the gross alpha, gross beta counting, 

and leached for three hours in the same manner as were the vegetation 

samples. The sample is transferred quantitatively to a planchet, surveyed, logged out and sent to counting. For gross gamma counting, the 

pulverized soil is weighed into a tared 5 dram plastic vial, surveyed, 

logged out and sent for counting. 

3.4 Counting Procedures 

Counting procedures for soil and vegetation samples were the same as previously described for samples analyzed with the Beckman WIDEBETA system. 

Results were reported by the laboratory in hCi/gm of dry soil and as ,uCi/gm 

of plant ash. The effect that this method of data reporting has on the heterogeneity of the results is discussed in the next Section. 

3.5 Results of Analyses 

Soil and vegetation analysis data for gross beta activity are summarized in 

Table 6. Sample station numbers in the table correspond to the numbers on 

the map (Figure 10). The figures in the table are picocuries per gram of 

dried soil and per gram of dried piant material. The monthly means and 

extreme fo.r these data are plotted in Figure 11. 

The original data, as received from the laboratory, is reported in pCi/gm 

of plant ash in accordance with uniform reporting procedure. As mentioned 

in Section 3.2, there was considerable variation in the nature of the plant 

samples submitted to the laboratory for anaylsis. The proportion of leaves 

to twigs differed with different species. These proportions may also vary 

considerably between samples of the same species depending upon stage of 

growth and vigor of the particular shrubs selected for sampling. These 

variations in the nature of the samples resulted in ash contents that ranged 

10 
from as little as 4% to as much as 72% of the dry weight of the plant 

material. The usual range for any small group of samples was approximately 5 to 25%. 

Reporting of the data as activity per gram of ash instead of per gram of 

plant material thus added to the heterogeneity of the results. Therefore, 

the data on beta activity of the vegetation samples were converted to 

activity per gram of dried plant material. 

Since soil data are reported as activitv per gram of dried soil, soil and 

vegetation data are directly comparable. As illustrated in Figures 12 and 

13, soil and vegetation activity are often closely correlated and occasionally 

are numerically equivalent. However, the close correlations often obtained 

emphasize the wide discrepancies sometimes reported. These are discussed in the next Section. 

3.6 Discussion 

A certain amount of heterogeneity in radioactivity of soil and vegetation 

samples is to be expected under the conditions that prevail at NTS. The 

topography is rough and varied ranging in altitude from less than 4, 000 

feet at Mercury to over 7,000 feet on Pahute and Ranier Mesas. Climate, 

soil, and vegetation conditions at various sampling stations are not uniform. 

In planning these stations, there was no attempt to obtain uniformity of conditions and comparability of results between stations. On the other hand, 

an attempt was made to sample all of the varied soil and vegetation conditions 

existing at NTS. In other words, these stations are not replications and each 

can be thought of as a bench mark for measuring changes in environmental 

contamination for the particular set of conditions where the sampling station 

is located. 

Besides this variation in the physical factors of the environment between sampling stations, there is an even greater variation in the nature and amount of 

radioactive contamination to be sampled at t P e various stations. This is due 

to the effect of the topography on the climate in the immediate area of interest and because radioactive contamination at NTS originates from several 

sources at a number of different locations. 

The nuclear rocket engines at NRDS are tested at irregular intervals under 

varying test conditions as to duration and power resulting in occasional releases of radioactive contamination into the environment. Fallout from these 

tests may extend for miles as a narrow plume downwind from the reactor. 

Therefore, while much of NTS has been contaminated in the past by reactor 

1 Martin, William E. “Notes on the Deposition of Fallout in Relation to Topography and Local Meterological Conditions, ” UCLA Laboratory of Nuclear 

Medicine and Radiation Biology, TID-4500 20th Ed. No. 513, 1963. 

11 
tests, large areas of the Test Site have escaped significant contamination. 

Normally only a very few sampling stations will be affected by any particular reactor test. 

Nuclear devices are tested underground in several areas at a number of 

locations. Most of these tests contribute no significant contamination to the 

environment. Nevertheless, small amounts of radioactive materials escape 

occasionally releasing contamination into the environment. As in the reactor 

tests, contamination is confined to a very narrow fallout pattern affecting, 

at the most, only a few of the 23 sampling stations, 

The USPHS occasionally releases radionuclides in Area 15 in carefully controlled field experiments. This normally affects only Station 8. 

Plowshare events in past years have contributed some contamination and 

ab,ove ground tests prior to the test-ban treaty created a number of contaminated ground zeros. Much of this contaminated material is still on the 

ground surface where it can be picked up by the wind and redeposited. 

These same winds can affect the correlation between soil and vegetation 

samples. In sampling soil and vegetation at NTS, an attempt is made principally to measure close-in fallout. Close-in fallout particles are mostly too 

large to be held effectively by foliage. Winds strong enough to whip the 

branches of shrubs, shake off most of the fallout particles. With recent fallout and after a high wind, the shrubs may be relatively free of contamination, 

but as the data show, even greater heterogeneity is found with soil samples 

than with vegetation, 

Fallout is deposited on the soil surface and in a desert environment moves 

very slowly downward through the soil profile. Therefore, the sample is confined to the surface soil. However, in a land with scanty vegetation and 

copious wind, the soil surface is not stable. What was the soil surface at the 

time the fallout was deposited might not be the surface when the sample was 

collected. It might be buried by drifting sand or eroded away by the wind. 

Since sample collecting personnel looked for a spot of “clear” ground to 

collect samples, they thus selected areas with the least stable surface. 

Procedures are being developed for collecting and preparing soil and vegetation samples that will reduce the heterogeneity past samples have shown. 

12 

X X X 

14 
I I I 

I I I I 

1 2 3 4 5 6 7 8 9 10 11 12 13 14 

SAMPLE STATION NUMBER 

15 
4 \ . 

5la 

5lb 

I 0 5 IO Miles 

Figure 4 - Water Sampling Station Locations 
FEB MAR APR MAY JUN JUL AUG SEP OCT NOV DEC JAN FEB MAR APR MAY JUN 

1965 1966 

Figure 5 - Means and Ranges of Gross Beta Radioactivity jrom February, 1965 to June, 1966; 

Industrial Water 

17 
AREAS 15 6 12 25 16 5 3 5 25 2 18 18 

. : 

Figure 6 - Descending Means of Twelve Sampling Locations: Industrial Water 

18 
- 

0 
1 x 

I I I I I i I I I I 

I I I I I I I I I I 

I I I ! ! ! I ! I ! 

I I I I I I I I I I I 

I-H-HFEB MAR APR MAY JUN JUL AUG SEP OCT NOV DEC 1 JAN FEB MAR APR MAY JUN 

1965 1966 

Figure 8 - Means and Ranges of Gross Beta Radioactivity in Potable Water Samples from February. 

1965 through June, 1966 

20 
-t 

t 

21 
* 20 

I 

I 

0 

f 

IO Miles 

Figure 10 - Soil and Vegetation Sample Stations 

22 
40 

36 

m 

10 

0 

= 

q 

q 

q 

= 

AUG SEPf act NOV DE C JAN FEB 

* Soil means 

0 Vegetation means 

Figure 11 - Means aud Extremes of Soil a?rd Vegetation Samples 
160 

80 

E 60 

2 

v 

n 40 

20 

0 

100 

60 

E 60 

I?? 

v 

Q 40 

20 

0 

166 

60 

STATION 1 

I ’ I 1 

AUG SEPT OCT NOV DEC JAN FEB 

STATION 2 

UC SEPT OCT NOV DEC JAN FEB 

STATION 7 

STATION 5 . 

‘;* 

: : 

. = . 

: ; 

. 

: l 

l 

: . 

: 

. 

. 

: 

. 

. 

E 

s 

l 

. . . 

! . 

AUG SEPT OCT NOV DEC JAN FEB 

STATION 6 

Vegetation in pCi/gm dry wt. 

.m..... Soil in pCi/gm dry wt. 

AUG SEPT OCT NOV DEC JAN FED 

i 

STATION 8 :: 

: 

: 

: 

: 

AUG SEPT OCT NOV DEC JAN FED AUG SEPT act NOV DEC JAN FED 

Figure 12 - S oil and Vegetation Radioactivity 

24 
100 

80 

20 

0 

60 

E 60 

2 

%40 

100 

60 

E 60 

-? 

is 

Q40 

STATION 9 STATION 10 

AUG SEPT OCT NOV DLC JAN FLB AUG SEPT OCT NOV DEC JAN FED 

STATION 12 STATION 13 

Vegetation in pCi/gm dry wt. 

. . . . . . . . Soil in pCi/gm dry wt. 

AUG SEPT OCT NOV DEC JAN FEE AUG SEPT OCT NOV DEC JAN FEB 

STATION 18 STATION 21 

AUG SEPT 6CT NOV DEC JAN FEB AUG SEPT OCT NOV DEC JAN FE6 

Figure 13 - Soil and Vegetation Radioactivity 

2!i 
9 9-300 bunker area 9/a 

10 

12 

18 

TABLE 1 

ENVIRONMENTAL SURVEILLANCE 

AIR SAMPLING STATION LOCATIONS 

AREA SAMPLE STATION LOCATION MAP CODE FOR FIGURE 1 

Northwest of field cafeteria 

Gate 250, guard station, 

East of well 58 reservoir 

Housing complex, adjacent to 

aid station 

3/a 

5/a 

5/b 

6/a 

Gate 700, guard station 10/a 

“Changehouse” 12/a 

Adjacent to Camp 17 cafeteria 18/a 

firestation trailer at airstrip 18/b 

20 Dispensary 20/a 

23 Building 214, 23/a 

25 NRDS H-8 complex 25/a 

27 North of cafeteria 27/a 

51, Groom Lake cafeteria 51/a 

26 
TABLE 2 

SAMPLING PERIOD MEANS AND RANGES OF 

GROSS BETA RADIOACTIVITY IN ENVIRONMENTAL 

AIR SAMPLES FROM NTS 

JULY 1964 THROUGH JUNE 1966 

AIR SAMPLES (Values in terms of pCi/cc) 

DATE 

(Week ending) 

7/'1/64 

7/'8/64 

7/25/64 

8/l/64 . 

8/8/64 

8/15/64 

8/22/64 

8/29/64 

9/5/64 

9/12/64 

9/19/64 

9/26/64 

10/3/64 

10/10/64 

'O/17/64 

10/24/64 

10/31/'64 

11/'7/64 

11/14/64 

11/21/64 

11/28/64 

12/5/64 

12/12/64 

12/19/64 

12/26/64 

l/2/65 

l/9/65 

l/16/65 

l/23/65 

l/30/65 

2/6/65 

2/13/65 

2/20/65 

2/27/65 

3/6/65 

3/13/65 

3/20/65 

3/27,'65 

4/3/65 

4/'0/65 

RANGE 

MEAN 

MAXIMUM MINIMUM 

1.4 x 10-12 3.4 x 'O-12 9.8 x lo-l3 

3.6 x lo-13 5.1 x 10-13 2.6 x lo-13 

4.8 x lo-13 7.8 x lo-13 2.6 x 'O-13 

3.0 x 10-13 1.4 x 10-12 1.7 x 10-13 

1.8 x lo-13 3.3 x 10-13 1.7 x 10-14 

1.6 x lo-13 2.1 x 10-13 1.2 x 10-13 

2.2 x 10-13 3.8 x lo-13 1.2 x 10-13 

6.1 x lo-13 1.4 x 10-12 3.8 x lo-13 

6.8 x 10-13 7.8 x lo-13 5.7 x 10-13 

Sample not collected 

2.7 x lo-13 3.2 x 'O-13 1.9 x 10-13 

5.8 x IO-13 6.5 x lo-13 4.6 x lo-13 

7.8 x 'O-13 9.4 x 'O-13 2.4 x lo-13 

7.2 x lo-13 2.2 x 10-12 1.4 x 10-13 

2.6 x IO-l3 ;; x ;;-;; 1.5 x 10-13 

3.5 x 10-13 2.0 x 10-13 

5.7 x 10-12 

4.2 x lo-13 

(riax) :I: E M&i: 

. x 

;.; x ;;-;; 

4.7 x 10-13 6.5 x lo-13 2:6 ," 'O-13 

3.0 x 10-13 6.5 x lo-13 1.9 x lo-'3 

3.7 x 10-13 4.8 x 'O-13 2.4 x 'O-13 

2.5 x lo-13 4.3 x 10-13 7.1 x 10-14 

2.0 x 10-13 2.6 x lo-13 7.1 x 10-14 

1.5 x 10-13 3,4x 10-13 x 

4.3 x 10-13 7.5 x 10-13 

z.2" 

# x - 

ii-;; 

Sample not collected 

3.3 x 10-14 4.9 x 10-14 2.2 x 10-14 

Sample not collected 

1.3 x 10-13 3.9 x 'O-13 8.7 x lo-14 

3.9 x 10-13 5.8 x lo-l3 2.7 x lo-l3 

5.2 x lo-l3 7.3 x 10-13 3.8 x lo-13 

6.6 x 10-13 3.0 x 10-12 4.1 x 10-13 

7.6 x lo-13 3.0 x 10-12 2.0 x 10-13 

45.28 

x 

;;-;; 

8.2 x lo-13 5.8 x lo-14 

7:9 :: 10113 

9.6 x lo-l3 3.0 x 10-13 

9.1 x 10-13 x 

3.4 x 10-13 5.6 x lo-l3 ;.; . x ;;-;: - 

6.5 x IO-l3 8.3 x 'O-l3 4.2 x '0'13 

4.9 x IO-13 6.9 x lo-l3 2.1 x 10-13 

2.2 x 'O-13 5.0 x 'O-13 9.4 x 10-14 

27 
TABLE 2 (Cont'd) 

DATE 

(Week ending) 

4/17/65 

4/24/65 

5/l/65 

5/8/65 

5/'5/65 

5/22/65 

5/29/65 

6/5/65 

6/12/65 

6/19/65 

6,'26/65 

7/4/65 

7/11/65 

7/18/'65 

7/25/65 

8/l/65 

8/8/65 

8/15/65 

8/22/65 

8/29/65 

9/5/65 

9/12/65 

9/19/65 

9/26/65 

10/3/65 

10/10,'65 

'O/17/65 

10/24/65 

10/31/65 

AIR SAMPLES (Values in terms of pCi/cc) 

MEAN RANGE 

MAXIMUM MINIMUM 

2.5 x lo-l3 4.3 x lo-l3 1.3 x lo-l3 

5.4 x lo-l3 1.1 x lo-l2 1.3 x lo-l3 

7.3 x lo-l3 1.3 i lo-l2 2.8 x lo-l3 

7.1x lo-l3 1.2 x lo-l2 2.9 x lo-l3 

7.6 x lo-l3 1.0 x lo-l2 3.3 x lo-l3 

8.3 x lo-l3 2.7 x lo-l2 6.1 x 'O-l3 

3.0 x lo-l2 7.6 x lo-l2 1.3 x lo-l2 

1.9 x lo-l2 2.8 x lo-l2 1.3 x lo-l2 

1.7 x lo-l2 2.7 x lo-l2 1.2 x lo-l2 

1.0 x lo-j2 6.9 x lo-l2 1.5 x lo-l4 

1.0 x 1o-'2 3.1 x lo-l2 5.1 x lo-l3 

Sample not collected 

4.20 x lo-l3 1.18 x 'O-l2 

3.04 x lo-l3 

1.97 x lo-l3 

1.89 x 'O-l3 6.09 x lo-l4 

2.75 x lo-l3 9.91 x lo-l3 5.30 x lo-l4 

2.14 x lo-l3 1.94 x lo-l2 3.75 x lo-l4 

7.61 x lo-l4 1.55 x 10 -13 1.58 x lo-l4 

1.55 x lo-l3 3.93 x lo-l3 2.24 x lo-l4 

7.25 x lo-l4 1.70 x 'o-'3 3.25 x lo-l4 

8.72 x lo-l4 1.94 x lo-'3 3.36 x 'O-l4 

8.19 x lo-l4 2.80 x lo-l3 3.63 x lo-l4 

8.27 x lo-l4 2.00 x lo-l3 9.67 x '0 -15 

1.24 x 'O-l3 2.55 x lo-l3 7.10 x lo-l4 

3.65 x 'O-l3 4.62 x lo-l3 6.04 x lo-l4 

5.87 x lo-l4 1.35 x lo-l3 1.81 x lo-l4 

7.88 x 10 -14 1.44 x lo-l3 5.67 x 'O-l4 

1.18 x JO-'3 1.97 x 10-13 6.30 x lo-14 

6.49 x 'O-l4 1.61 x lo-l3 3.89 x 'O-l4 

4.68 x lo-l4 1.03 x lo-l3 2.39 x lo-l4 

28 
x... 

.~ I. _.,. 

TABLE 2 (Cont'd) 

r AIR SAMPLES (Values in terms of pCi/cc) 

DATE 

(Week ending) 

- 

T 

11/7/65 

11/'4/65 

11/21/65 

ll/28/65 

12/5/65 

12/12/65 

12/19/65 

12/'261'65 

l/2/66 

l/9/66 

l/16/66 

l/23/66 

l/30/66 

2/6/66 

2/13/66 

2/20/66 

2/27/66 

3/6/66 

3/13/66 

3/20/66 

3/27/66 

4/3/66 

4/10/66 

4/17/66 

4/24/66 

5/l/66 

5/8/66 

5/15/66 

5/22/66 

5/29/66 

6/5/66 

6/"2/66 

6/19/66 

i/26/66 

- 

MEAN 

T 

MAXIMUM MINIMUM 

6.34 x lo-l4 1.73 x lo-l3 2.66 x lo-l4 

6.99 x 'O-l4 1.72 x lo-l3 4.80 x lo-l4 

4.88 x lo-l4 1.40 x lo-l3 2.73 x 'O-l4 

2.28 x lo-l4 9.07 x lo-l4 1.45 x lo-l4 

6.76 x lo-l4 1.12 x lo-l3 2.13 x lo-l4 

6.38 x lo-l4 1.12 x 10-13 4.07 x lo-l4 

5.02 x lo-l4 1.15 x lo-l3 1.38 x lo-l4 

4.18 x 'O-l4 9.37 x 'o-l4 1.99 x lo-l4 

1.47 x lo-l3 3.67 x lo-l3 2.55 x lo-l4 

1.17 x lo-l2 3.17 x lo-l2 1.74 x lo-l3 

5.29 x lo-l4 2.15 x 'O-l3 2.34 x lo-l4 

6.04 x 19-14 8.49 x lo-l4 5.19 x lo-l4 

4.67 x lo-l4 1.83 x lo-l3 4‘46 x lo-l4 

6.11 x lo-l4 1.59 x lo-l3 3.27 x lo-l4 

4.80 x lo-l4 7.01 x lo-l4 3.31 x lo-l4 

5.53 x 'o-l4 6.67 x lo-l4 4.62 x lo-l4 

9.26 x lo-l4 1.30 x lo-l3 7.10 x lo-l4 

7.00 x 10-14 1.00 x lo-l3 5.61 x lo-l4 

1.26 x lo-l3 6.97 x lo-l3 5.54 x 'o-l4 

9.29 x lo-l4 1.06 x lo-l3 7.53 x lo-'4 

2.39 x lo-l3 1.69 x lo-l2 1.10 x lo-'3 

7.78 x lo-l3 2.42 x lo-l2 1.36 x lo-l3 

1.61 x lo-l3 2.28 x lo-l3 1.28 x lo-l3 

1.17 x lo-l3 1.54 x lo-l3 1.00 x 'o-l3 

1.07 x lo-l3 1.38 x lo-l3 8.02 x lo-l4 

1.76 x lo-l3 2.67 x lo-l2 4.87 x lo-l4 

1.75 x lo-l3 8.69 x lo-l3 2.35 x lo-l4 

1.23 x lo-l3 1.69 x lo-l3 5.79 x 10-14 

1.03 x lo-l3 1.18 x lo-l3 8.20 x lo-l4 

7.06 x lo-l3 1.47 x lo-l2 3.16 x lo-l4 

7.47 x lo-l3 3.93 x lo-l2 3.54 x lo-l3 

2.46 x lo-l3 1.09 x 'o-l2 1.11 x lo-l3 

2.13 x lo-l3 2.80 x lo-l3 1.60 x 'O-l3 

2.26 x lo-l3 3.02 x IO-l3 1.74 x lo-'3 

RANGE 

29 
TJiEiLE2A 

SAMPLING PERIOD MEANS AND RANGES OF 

GROSS BETA RADIOACTIVITY IN ENVlRO!.:NTAL 

FtlTlEiLE WATER SATPlXS FROM NTS 

FEBRUARY 1965 THROUGH JUNE 1966 

WATER SAMPLES (Values in terms of uCi/cc) 

DATE RANGE 

(Week ending) MAXIMUM MINIMUM 

2/06;/65 6.4 x 10-9 1.3 x 10-B 2.1 x 10-9 

2/13/65 

2120165 

2127165 

3106165 

3113165 

3/20/65 

312716.5 

4/03/65 

4/10/65 

4/17/65 

4/24/65 

5/01/65 

5/08/65 

5/15/65 

5122165 

5/29/65 

6/05/65 

6/12/65 

6/19/65 

6/26/65 

7/04/65 

7/U/65 

7/18/65 

7125165 

8/01/65 

a/08/65 

8/15/65 

8122165 

8/29/65 

9105165 

g/12/65 

9119165 

9126165 

10/03/65 

lo/lo/65 

10/17/65 

10/24/65 

10/31/65 

11/07/65 

11/14/65 

U/21/65 

U/28/65 

317 x 10-9 6.0 x lO-g 

5.7 x 10'9 8.0 x lO-g 

5.4 x 10-9 1.1 x 10-8 

9.0 x 10-e 3.6 x lo-8 

5.3 x 10'9 1.0 x 10-8 

6.0 x 10-9 1.1 x 10-8 

5.2 x 1O-g 

1.0 x 10-8 

7.2 x 10-9 

4.7 x 10-8 

7.2 x 1O-g 1.2 x 10-8 

4.5 x 10'9 1.0 x 10-8 

2.3 x 10'9 

1.9 x 10'9 

1.7 x 10-g 

2.3 x 10'9 

2.3 x 10-9 

2.6 x 10-9 

3.7 x 10'9 

4.7 x 10'9 

2.9 x 10-9 

1.7 x 10-9 

No Samples Taken 

4.2 x 10-9 7.4 x 10-g 

5.3 x 10-9 9.5 x 10-9 

8.6 x 10-9 1.2 x 10-8 

3.9 x 10-9 '7.9 x 10-9 

5.4 x 10-9 7.8 x lO-g 

8.8 x 10-9 1.9 x 10-a 

4.7 x 10'9 1.8 x 10-8 

4.7 x 10'9 1.0 x 10-8 

6.6 x 10'9 9.2 x 10'9 

No 

5.69 x 1O-g 

Samples Taken 

1.3. x 10-8 

6.59 x 10-9 9.08 x lO-g 

1.19 x 10'8 2.54 x 1O-8 

6.41 x 10-9 1.18 x 1O-8 

3-90 x 10'9 7.56 x 10-9 

3.38 x 10'9 7.31 x 10'9 

5.56 x 1O-g 8.83 x 10-9 

4.46 x 10-9 7.57 x 10'9 

1.47 x 10-8 6.36 x 10-8 

4.26 x 10-9 6.72 x 10-9 

3.71 x 10'9 8.61 x 10'9 

5.35 x 10-9 8.09 x 1O-g 

5.75 x 10'9 1.00 x 1r8 

6.97 x JO-9 1.24 x 10-8 

6.01 x 10-9 1.06 x 10-8 

6.27 x 1O-9 1.58 x 10-8 

8.94 x 1O-g 5.31 x 10-8 

7.99 x 10'9 1.37 x 10-8 

1.93 x 10-8 8.08 x 10-8 

4.08 x 10-8 2.85 x 10-7 

1.58 x 10-8 2.73 x 10-8 

30 

1.7 x 10-g 

2.5 x 10'9 

5.6 x 10'9 

1.9 x 10-9 

3.1 x 10'9 

3.3 3 10'9 

2.0 x 10'9 

3.0 x 10'9 

1.7 x 10'9 

2.25 x 10'9 

5.47 x 1".9 

6.73 x 1O-g 

2.79 x 10-9 

3.16 x 1O-g 

2.31 x 10-9 

2.17 x 10-9 

1.81 x 10-9 

3.72 x 1O-g 

2.57 x 1O-g 

1.76 x 10-9 

2.14 x 10'9 

3.18 x Wg 

3.35 x 10-9 

3.11 x 10-9 

2.26 x lO-9 

3.43 x 10-9 

5.46 x 10-9 

5.31 x 10'9 

3.90 x 10-9 

9.63 x 10-9 
TABLE 2A Cont. 

WTER SA?IPLES (Values in terms of ~Ci/cc) 

DATE, XEA:? RANGE 

(!Jeek endine) I.lUT.FNi4 ?IINII"fUM 

12/05/65 8.51 x 1O-y 

12/12/65 4.83 x 10-9 

12/19/65 2.51 x 10-Y 

12/26/65 2.50 x 1O-g 

l/02/66 6.61 x 10-9 

l/09/66 2.52 x 10-9 

l/16/66 5.51 x 10'9 

l/23/66 6.67 x 10-9 

l/30/66 4.83 x 10-9 

2/06/66 3.82 x 10-g 

2113166 4.43 x 10-Y 

2/20/66 2.17 x lO-9 

2/27/66 4.45 x 10-9 

3/W/66 4.01 x 10-Y 

3113166 3.42 x 10'9 

3/20/66 4.08 x 10'9 

3127166 4.03 x 10'9 

4103166 8.10 x 10-9 

4/10/66 4.04 x 10-9 

4117166 3.57 x 10-9 

4124166 5.13 x 10-8 

S/01/66 5.65 x 10-9 

S/08/66 4.19 x 10-Y 

S/15/66 5.32 x 1O-9 

S/22/66 6.07 x 10-9 

S/29/66 4.35 x 10'9 

6105166 1.23 x lo-* 

6112166 1.50 x 10-a 

6119166 1.40 x 10-a 

3.37 x 10-B 

2.00 x 10-a 

6.55 x lO-9 

1.34 x 10-a 

8.83 x 1O-g 

1.06 x 10-8 

7.03 x 10-9 

1.85 x lO-8 

8.19 x lO-g 

7.94 x 10-9 

1.49 x 10'8 

6.42 x 10-9 

1.01 x 10'8 

6.76 x 1O-g 

5.64 x 1O-g 

8.96 x 1O-g 

7.45 x 10'9 

6.99 x lo-* 

7.80 x 1O-9 

6.88 x 10'9 

3.41 x 10'7 

8.68 x 10-9 

6.98 x 1O-g 

9.97 x 10'9 

1.06 x 10-a 

6.40 x 10-Y 

6.57 x lo-* 

3.08 x 10" 

3.67 x 10" 

3.50 x 10-Y 

2.52 x lO-9 

3.49 x 10-10 

2.96 x lo-lo 

4.62 x 1O-g 

2.10 x 10-9 

3.07 x lo-y 

3.12 x 1O-9 

3.05 x 10'9 

2.35 x lO-g 

2.89 x 1O-g 

2.00 x 10-Y 

2.61 x lO-g 

1.90 x 10'9 

2.01 x 10'9 

2.47 x lO-g 

2.96 x 1O-g 

2.57 x lO-g 

1.77 x 10'9 

3.13 x 10'9 

1.77 x 10'9 

2.53 x 1O-g 

3.38 x 1O-g 

1.61 x 1O-g 

3.15 x 10'9 

2.56 x 1O-9 

3.59 x 10'9 

7.39 x 10'9 

8.87 x lO-9 

31 
TABLE 3 

MEANS AND RANGES OF GROSS BETA RADIOACTIVITY 

IN NTS ENVIRONMENTAL AIR SAMPLING STATION LOCATIONS 

FROM JULY 1965 THROUGH JUNE 1966 

STATION NUMBER RANGE 

AND LOCATION MEAN 

MAXIMUM MINIMUM 

1. Old Mousehouse 1.10 x lo-l3 1.63 x lo-l2 1.99 x lo-l4 

2. NRDS H-8 Complex 7.75 x lo-l4 1.63 x IO-l2 1.81 x lo-l4 

3. Area 3 Cafeteria I.06 x lo-l3 2.05 x lo-l2 2.28 x 10 

-14 

4. Area 5 Reservoir 1.16 x lo-l3 3.17 x lo-l2 1.92 x lo-l4 

5. Area 6 Cafeteria 1.57 x lo-l3 1.69 x lo-l2 1.38 x lo-l4 

6. Area 9 Dispensary 1.08 x lo-l3 4.16 x lo-l3 1.05 x lo-l4 

7. Area 12 Cafeteria 1.49 x lo-l3 2.24 x lo-l2 1.45 x lo-l4 

8. Area 18 Camp 17 2.19 x lo-l3 3.93 x lo-l2 2.02 x lo-l4 

9. Area 18 Airstrip 1.80 x lo-l3 5.23 x lo-l3 7.97 x lo-l4 

10. Area 20 Dispensary 1.77 x lo-l3 1.95 x lo-l2 1.81 x lo-l5 

11. Area 51 Cafeteria 1.20 x lo-l3 2.17 x lo-l2 9.15 x lo-l5 

12. 250 Guard Statian 9.79 x 10 -14 1.51 x lo-l2 9.66 x lo-l5 

13. Area 27 Cafeteria 1.47 x lo-l3 1.52 x lo-l2 2.58 x lo-l4 

14. 700 Guard Station 1.76 1.99 

-12 

x lo-l3 x 10 4.46 x lo-l5 

32 
TABLE 4 

WATER SAMPLING STATION LOCATIONS 

AREA STATION LOCATION SAMPLE TYPE(a) FREQUENCY(b) MAP CODE 

2 Well 2 Reservoir IW MO 2/a 

3 Cafeteria PW Wk 3/a 

Well1 “A” Reservoir IW MO 3/b 

5 Well 5B IW MO 5/aCane Springs IW MO 5/b 

6 Camp Cafeteria’ PW Wk 6/d 

Well 3 Reservdir IW MO 6/b 

CP Waste Pond MW MO 6/c 

9 Dispensary PW Wk 9/a 

12 Cafeteria PW Wk 12/a 

White Rock Springs IW MO 12/b 

Upper Haines Lake MW MO 12/c 

Lower Haines Lake , MW MO 12/d 

15 

16 

18 

20 

23 

25 

27 

51 

USPHS Reservoir IW MO 

Tippipah Spring IW MO 

Dispensary PW Wk 

Camp 17 Reservoir IW MO 

Well 8 Reservoir IW MO 

Dispensary PW Wk 

Cafeteria PW Wk 

Swimming Pool MW MO 

NRDS Cafeteria PW Wk 

Fortymile Canyon Spring IW MO 

CP Water Tower IW MO 

Well J-12 MW MO 

Cafeteria PW Wk 

Cafeteria PW Wk 

Swimming Pool MW MO 

Well 3 MW MO 

Papoose Lake MW MO 

(a) IW = Industrial Water, PW = Potable Water, MW = Miscellaneous Water 

b) WK = Weekly, MO = Monthly 

15/a 

16/a 

18/a 

18/b 

18/c - 

20/a 

23/a 

23/b 

25/a 

25/b 

25/c 

25/d 

27/a 

51/a 

51/b 

51/c 

51/d 

33 
TABLE 5A 

SAWLING mRIOD MEANS AND RANGES OF 

GROSS BETA ~RADIOACTIVITY IN MONTHLY ENVlROl'WiXTAL 

LTJDUSTRIAL WATER SAMPLES FRO?4 l!lTS 

FE~~ARY 1965 TXROUGH m 1966 

DATE 

(Month) 

WATER SAKFLES (Values in terms of pCi/cc) 

MEAN RANGE- ._ 

MAXIMUM MINIMuM 

2165 8.70 x 10" 

3165 1.40 x 10-8 

4165 1.30 x 10-8 

5/65 6.20 x 10-9 

6165 1.10 x 10-8 

7165 8.90 x 10-9 

8165 2.05 x 1O-8 

9165 4.47 x 10'9 

lo/65 6.06 x 10'9 

U/65 1.51 x 10-8 

12165 6.40 x 10") 

l/66 5.96 x 1O-g 

2166 5.65 x 1O-g 

3/66 6.38 x 10'9 

4/66 9.40 x 10'9 

5166 9.39 x 10-9 

6166 1.03 x 10'8 

5.2 x 1O-8 

9.0 x 10-8 

5.0 x 10-8 

1.1 x 10-8 

4.7 x 10-8 

5.23 x'~O-~ 

1.14 x 10'7 

1.34 x 10-8 

1.58 x 1O-8 

2.51 x 10-8 

1.39 x 10-8 

1.51 x 10-8 

1.12 x 10-8 

1.18 x 1O-8 

2.52 x 1O-8 

296 x 1O-8 

4.48 x 10-8 

1.7 x 10-9 

3.5 x 10-9 

3.8 x 1O-g 

1.8 x 1O-g 

1.7 x 10-9 

4.21 x 1O-g 

4.76 x 10" 

2.09 x 10-9 

3.07 x 10-9 

4.82 x 10-9 

1.82 x 10-9 

2.62 x 10yg 

2.89 x 1O-g 

3.44 x 10-9 

4.51 x 10-9 

4.19 x 10'9 

6.12 x 1O-g 

34 
SAMPLE_ LOCATION MEAN 

AREA 15, USPHS RESERVOIR 1.85 x 1O-8 

AREA 6, WELL 3 RESERVOIR 1.61 x 1O-8 

ARFA 12, WHITE ROCK SPRING 1.52 x 10'8 

AREA 25, CP WATER TO!JER 

AREA 16, TIPPIPAII SPRING 

AREA 5, IJFJ>L 5B RESERVOIR 

AREA 3, !JELL "A" RESERVOIR 

AREA 5, CANE SPRING 

AREA 25, FORTY-MILE CANYON SPRING 

AREA 2, WELL 2 RESERVOIR 

AREA 18, WELT, 8 RESERVOIR 

AREA 18, CAMP 17 RESERVOIR 

1.28 x 10-8 

1.10 x 10-8 

1.09 x 10'8 

9.65 4 1O-g 

9.64 x 10-g 

9.38 x 10-g 

6.50 x 1O-g 

6.36 x 1O-g 

5.04 x 10-g 

35 
Mea;l?s and raqes of detectable KLph.0 ai-& beta activity in eight 

miscellaneous water ssnple locatioris for fiscal yeer July 1965 through June 1966. 

LOCATION 

NO. 

OF 

SAMPLES 

ALPHA 

(pci/cc) 

RANGE. 

Detected 

GROOM LAKE 

SWIMBXNC, POOL 11 

I I 

Non1 

!&JELL J-12 8 Noni 

Detected 

Detected 

WELL 3 10 Non Detected 

CP WASTE POND 11 Non e Detected 

UPPER !iAINES LAK 12 1 I 

'2.82 x 10'9 9.52 x 10-10 

through 

7.60 x 10" 

LOVER HAINES LAKE 12 2.56 x 10-9 

PAPOOSE LAKE 11 NonI 

- I 

1.55 x 10-10 

through 

1.23 x 1O-8 

Detected 

BETA 

(pCi/cc) 

?lF.AN RANGE I 

4.72 x 10' 9 I 

1.58 x 10-8 

8.14 x 1O-g 

3.22 x 1O-g 

through 

7.51 u lQ!-9 

3.31 x 10-9 

through 

1.96 x W7 

3.05 x 10-9 

through 

5.30 x 10-g 

9.12 x 10-Q 5.19 x 10'9 

through 

6.30 x 10-7 

6.82 x 10-7 2.69 x lO-7 

through 

3.33 x 10-C 

2.94 x 10-6 4.88 x 1O-7 

through 

7.22 x 1O-6 

3.21 x 10-G 4.22 x 10-7 

through 

5.36 x 1O-6 

8.48 x 10-8 7.58 x 1O-g 

through 

3.99 x 10-7 

36 
TABLE6 

GROSS BETA ACTIVITY(') 

(of Soil and Vegetation Samples for Fiscal Year 1966) 

R Soil Veg. Soil Veg. Soil Veg. Soil Veg. Soil Veg. Soil Veg. Soil Veg. Soil S.D. Veg. S.D 

16 15 9 5 5 2010 18 5 9 7 9 4 7 6 2 12 5 

2 3 12 8 11 5 14 24 11 14 12 5 2 5 7 9 7 10 4 

3 3 9 19 11 37 10 4 5 5 9 4 8 11 15 10 4 

4 6 22 2 18 9 13 3 2 I3 3 6 4 3 14 6 

5 15 32 18 13 3 1 3 8 86 10 6 11 9 8 20 21 12 8 

6 10 7 4 14 6 9 15 5 7 715 8 6 7 9 4 8 3 

7 18 19 13 13 14 15 15 8 72 5 13 18 12 6 22 20 12 5 

8 20 17 17 9 12 20 118 15 118 5 2 35 16 14 43 53 16 9 

9 6 11 7 .I7 11 8 9 13 39 14 9 7 8 6 13 11 11 4 

IO 5 1313 5 4 16 2 8 2 5 5 5 2 3 5 4 8 4 

I1 9 12 9 1213 8 8 8 8 2 4 6 8 2 8 4 

12 9 14 11 14 10 11 5 8 14 9, 15 3 8 5 10 3 9 4 

I3 4 16 9 9 12 14 10 5 9 4 8 6 12 6 9 3 9 5 

14 5 12 10 12 9 9 11 11 15 13 7 9 9 3 11 2 

I5 9 5 7 7 6 8 5 9 4 4 6 2 7 2 

I6 10 10 1 12 4 ._ 8 6 4 8 8 4 8 5 4 8 2 

I7 1 4 17 1 8 5 8 123 7 9 3 3 lo 7 

18 4 15 4 20 4 10 6 14 19 10 9 4 5 6 8 5 11 5 

I9 8 13 10 13 6 12 10 6 25 8 8 4 6 7 II 6 9 4 

20 16 5 5 33 32 29 36 5 34 6 33 4 15 17 24 10 14 11 

!l 5 22 41 16 4 20 5 11 3 3 6 6 6 6 10 13 12 7 

22 4 13 9 11 3 7 169 10 4 9 12 3 34 66 9 4 

23 8 12 11 14 9 27 6 11 10 5 16 2 8 9 10 2 11 8 

eon 8 14 10 13 8 13 24 9 22 8 9 8 8 8 13 11 

,D. 5 6 8 6 6 7 41 4 29 5 7 7 4 4 

(1) Activity is expressed as picocurier per gram of soil and plant materiol (dry weight). 

(2) For location see Figure 10. 

37 
cx.?.d-I-. . . 

APPENDIX A 

STATISTICAL TREATMENT OF DATA 

A. 1 Geometric Mean 

The frequency distribution of radioactivity results for air and 

water samples indicated a positive skew, a degree of distortion 

from symmetry of a normal curve. This type of asymmetrical 

distribution is caused by the extremes in the higher values distorting the curve towards the right. 

The data must therefore be handled by logarithmic transformation to obtain normality, and treated as normally distributed 

random variables. 

Hence, an estimate of the true mean of a sample type is calculated by: 

E- = log -1 Zlog Xl s2 

N’ +i-- 1 

when: Xl = observed value 

N = number of observations 

S2 = variance of log value 

Though the geometric mean is not widely known and is relatively 

tedious to,compute, its relative advantage is that it is a more 

typical average than the arithmetic mean since it is less affected 

by extremes. 

A. 2 Radioactivity of a Sample 

The radioactivity of a sample (X) is indicated in the equation: 

x = 

R, - Rb 

ABC 

where: R, = gross count rate of sample, c/m 

Rb = background count rate, c/m 

A = counting efficiency for a particular 

counter (cpm/dpm) 

B = conversion factor (2.22 dpm - pCi or 

2.22 x lo6 dpm - PCi) 

c = subsample amount, cc, liter, or gram 

313 
The associated percent counling error at the 2-sigma confidence 

level (%E2o) for each radioactivity value (X) was: 

%E2C = loo’ 

-- 

Rs -s 

+ *l/2 1 

where: Z = 2, the number of standard deviations 

for the confidence interval (95.4%) 

TS 

= sample count interval, minutes 

‘I’b = background count interval, minutes 

The radioactivity of a sample was considered statistically signifi- 

.cant if the net count rate of the sampie was greater than the detection limit, i, e. , two times the net count for which the two-sigma 

error was 100 percent. 

The detection limit was computed by formula: 

DL = 

where: d = net count rate for which the 2-sigma 

error is 100, 

Any activity value which was equal to or less than the detection limit 

was recorded as zero. 

39