. NVO-410-15 

ENVIRONMENTAL RADIOACTIVITY 

‘“* -AT THE -NEVADA TEST SITE 

July, 1966 through June, 1967 

REYNOLDS ELECTRICAL & ENGINEERING CO., INC. 

ENVIRONMENTAL SCIENCES DEPARTMENT 

LAS VEGAS, NEVADA 89114 

MAY, 1968 

PREPARED FOR THE U. S. ATOMIC ENERGY COMMISSION, 

NEVADA OPERATIONS OFFICE UNDER CONTRACT NO. AT(26-I)-410 
ENVIRONMENTAL RADIOAC~TY 

AT THE 

NEVADA TEST SITE 

JULY, 1966 THROUGH JUNE, 1967 

MAY, 1968 

REYNOLDS ELECTRICAL AND ENGID CO., INC. 

AN &&#iMW COMPANY 
ACKNOWLEDGEMENTS 

The Environmental Surveillance group of the Radiological Sciences 

Department collected all samples , prepared the initial text and 

provided technical guidance during the final preparation of the 

report. Laboratory analysis was performed by the Department's 

Laborato>y Operations group and the Reports Coordination group prepared the various figures, edited the text, and coordinated the 

final preparation of the report. 

iii 
ABSTRACT 

This report contains a sunxnary of the data obtained concerning 

the ra&ological conditions in the environment of the Nevada Test 

Site (NTS) from July, 1906 through June, 1967. 

The Environmental Surveillance Group performed routine and special 

surveys of the NTS. Samples of air and water were collected for 

laboratory analysis from living quarters, administrative buildings, 

and cafeterias. Additionally, samples of water from waste ponds, 

sewage basins, reservoirs, springs, and wells were collected on a 

routine basis to determine normal levels of radioactivity or any 

change of radioactivity. Air samples were also routinely collected 

at selected locations throughout NTS for the same purpose as for 

water samples. All environmental samples were analyzed routineiy 

for gross alpha, beta, and gamma radioactivity. Significant increases or changes in the ratioactivity levels of these samples were 

reported to the appropriate field monitoring groups for investigation 

and remedial action. All samples were documented by the Environmental 

Surveillance Branch for record purposes and for comparison with wevious results to determine trend and correlation where feasible. 
TABLE OF CONTENTS 

Section 

Acknowledgements 

Abstract 

List of Figures 

List of Tables 

1 Air Sampling 

2 Water Sampling 

3 Background Radiation PleasImements 

Appendix 

A Statistical Treatment of Data 

Page 

iii 

V 

iX 

xiii 

1 

4 

9 

60 

vii 
LIST OF F'IGURES 

Figure 

1 

2 

6 

7 

8 

9 

13 

11 

12 

13 

Page 

NTS Environmental Surveillance Air Sampling 

Locations 12 

?*/eekly Means and Ranges of Gross Beta Radioactivity 

From July, 1966 Through June, 1967; Air Sampling 15 

Means and Ranges of Gross Beta Radioactivity From 

July, 1966 Through June, 1967; Air Sampling 17 

N'R-3 Environmental Surveillance Potable Water 

Sampling Locations 19 

Means and Ranges of Gross Beta Radioactivity at NTS 

Environmental Potable Water Sampling Locations From 

July, 1966 Through June, 1967 21 

Weekly Means and Ranges of Gross Beta Radioactivity 

in Potable Water Samples From July, 19b6 Through 

June, 1967 24 

NTS EnvironmentaL Surv-illance Natural Springs 

Sampling Locations 26 

Monthly Means and Ranges of Gross Beta Radioactivity 

in Natural Springs Yater Samples From July, 1966 

Through June, 1967 28 

Means and Ranges of Gross Beta Radioactivity From 

July, 1966, Through June, 1967; Natural Springs 

Sampling Locations Iw 

NTS Environmental Surveillance Open Reservoirs 

Sampling Locations 32 

Monthly Means and Ranges of Gross Beta Radioactivity 

in Open Reservoir Mater Samples From July, 1966 

Through June, 1967 34 

Means ancl Ranges of Gross Beta Radioactivity From 

July, 1966 Through June, 1967; Open Reservoir 

Sampling 3 

NTS Environmental Surveillance Supply Wells Sampling 

Locations 3 

ix 
Figure 

14 

15 

16 

17 

18 

19 

20 

21 

22 

23 

24 

25 

Monthly Means and Ranges of Gross Beta Radioactivity 

From September, 1966 Through June, 1967; Supply 

i:!ells Sampling 

Means and Ranges of Gross Beta Radioactivity 

From July, 1966 Through June, 1967; Supply Wells 

Sampling 

NTS Environmental Surveillance Final Effluent 

Sampling Locations 

Means ano Ranges of Gross Beta Radioactivity From 

October 1966 Through April 1967; Final Effluent 

Sampling 

Means and Ranges of Gross Beta Radioactivity From 

October, 1966 Through April, 1967; Firm1 Effluent 

Sampling 

NT.5 Environmental Surveillance Miscellaneous Water 

Sampling Locations 

Environmental Surveillance Ionization Chamber 

Sampling Locations 

\leekly Fxposure Readings For Period July, 1966 

ThroughJune, 1967 For Area 3 (North of Cafeteria); 

Ionization Chambers - Victoreen Model 239 

Weekly Exposure Readings For Period July, 1966 

Through June, 1967 For Area 6 (West of Ice House); 

Ionization Chambers - Victoreen Model 239 

Weekly Exposure Readings For Period July, 1966 

Through June, 1967 For Area 12 (South of Campsite); 

Ionization Chambers - Victoreen Model 239 

Weekly Exposure Readings For Period July, 1966 

ThroughJune, 1967 at Area 23 (South of Dispensary); 

Ionization Chambers - Victoreen Model 239 

Weekly Exposure Readings For Period July, 1966 

Through June, 1967 at Area 27 (West of Guard Station 

561); Ionization Chambers - Victoreen Model 239 

Page 

40 

42 

44 

46 

48 

gu 

52 

55 

56 

57 

58 

59 

xi 
LIST OF TABLES 

Page 

11 

13 

16 

Table 

1 Environmental Surveillance Air Sampling Station 

Locations 

Sampling Period Means and Ranges of Gross Beta 

Radioactltity in Environmental Air Samples From 

NTS; July, 1966 Through June, 1967 

2 

Means and Ranges of Gross Beta Radioactivity in 

NTS Environmental Air Sampling Station Loca:.ions 

.From July, 1966 Through June, 1967 

3 

Environmental Surveillance Potable Water Sampling 

Station Locations 

4 

18 

Means and Ranges of Gross Beta Radioactivity at 

NTS Environmental Potable Water Sampling Station 

Locations From July, 1966 Through June, 1967 

5 

20 

6 Means and Ranges of Gross Beta Radioactivity at NTS 

Environmental Potable Water Sampling Locations Fern 

July, 1966 Through June, 1967 22 

25 

Environmental Surveillance Natural Spring Sampli.ng 

Station Locations 

Monthly Means and Ranges of Gross Beta Radioactivity 

at NTS Natural Spring Sample Station Locations 

From July, 1966 Through June, 1967 27 

Means and Ranges of Gross Beta Radioactivity at 

NTS Environmental Natural Spring Sampling Station 

Locations From July, 1966 Through June, 1967 

9 

29 

Environmental Surveillance Open Reservoir Sampling 

Station Locations 

10 

11 Monthly Means and Ranges of Gross Beta Radioactivity 

at NTS Open Reservoir Water Sampling Station Locations From July, 1966 Through June, 1967 33 

Means and Ranges of Gross Beta Radioactivity at NTS 

Environmental Open Reservoir Sampling Locations From 

July, 1966 Through June, 1967 

12 

35 

Environmental Surveillance Supply Wells Sampling 

Station Locations 

13 

37 

xiii 
Table 

14 

15 

\ 

16 

17 

18 

19 

20 

21 

Page 

Monthly Means and Ranges of Gross Beta Rad$oactivity 

in NT'S Supply Wells Water Samples From July, 1966 

Through June, 1967 39 

Means and Ranges of Gross Beta Radioactivity at NT3 

Environmental Supply Wells Sampling Locations From 

July, 1966 Through June, 1967 41 

Environmental Surveillance Final Effluent Station 

Locations 43 

MonthlyMeans and Ranges of Gross Beta Radioactivity 

in Environmental Final Effluent Samples From October, 

1966 Through April, 1967 45 

Means and Ranges of Gross Beta Radioactivity at NTS 

Environmental Final Effluent Sampling Station Locations F’rom October, 1966 T~~OU& April, 1967 47 

Means and Ranges of Gross Beta Radioactivity at NT3 

Miscellaneous Sampling Locations From July, 1W6 

Through June, 1967 49 

Environmental Surveillance Ionization Center 

Sampling Station Locations 51 

Summary of BacKground Radiation Measurements (mR/day) 53 
SECTION 1 

AIR SAMPLING 

1.1 Introduction 

The Environmental Surveillance Group maintains low-volume, 

continuously-operating air samplers at 20 permanent locations (Figure 1 and Table 1) situated to provide monitoring of the particulate airborne radioactivity within the 

Nevada Test Site (NTS) boundaries. 

1.2 Description of Equipment 

The sampling equipent used consists of a positive displacement Gast pump that pulls air through a 4" (Whatman 41) 

filter paper 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 103 cubic meters. The flow rate of air 

through the filter is maintained at approximately four cubic 

feet per 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 occurring radon and thoron daughters to decay to 

insignificant levels. Air samples were analyzed for gross 

alpha and beta using a Nuclear Chicago ULTRASCALER gas pro- 

' portional system having an efficiency (the ratio of observed counts to known disintegrations) of 28 for alpha 

and 5l$ for beta. Background counts for alpha and beta on 

this instrument were determined by counting for 100 minutes 

each. A Baird Atomic SPECTROMETER was used for determination 

of gross gamma activity. If the activity for gaxmna was such 

that the apparent 2 o counting error was less than 505, then 

the sample was transferred to a 400-channel gannna-spectrum 

analyzer to qualitatively determine the contributing radionuclides. 

Sample activity results, reported by the Radiological Measurements Laboratory, were compar,ed with an established 

"alert level;" The determination of the alert level is 

based on the radiation concentration guide (KG) as outlined in AEC Manual Chapter 0524. The alert level for beta 

activity has been maintained at 1 x lo-l1 PCi cc of air 

after a five day decay period and at 1 x 10'1 4 $X/cc for 

alpha activity. Though a sample may exceed this alert 

-l- 
level, it does not necessarily mean that the actual RCG 

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 

high concentration is valid. 

1.4 Data Discussion 

The means ano ranges of gross beta radioactivity in weekly 

collections of air samples from the 20 permanent locations 

fromJuly, 1966 through June, 1967 are tabulated in Table 2 

and pl?tted in Figure 2. During this fiscal year (July, 1966 

through June, 1967) no sample activity value exceeded the 

alert level of 1 x lo-l1 $X/cc in air. The highest value 

recorded for beta radioactivity occurred in the air sample 

collected from Area 28, HENRE Site (Figure 1) for the third 

week in January, 1967. This value, 2.55 x 10WU $X/cc, is 

above the established limit. However, investigations of 

the circumstances of this sample iticate that fallout from 

foreign weapons testing was the principal contributor. 

Fluctuations for this fiscal year followed a trend of decrease in activity values from July, 1966 until about November which were periods of reduced testing operations. There 

were significant peaks in activity values in November, 1966 

and in January, 1967. The high activity values in November 

may be correlated with fallout from foreign weapons tests. 

The high activity values in January were also due to foreign weapons tests plus some contribution from NTS testing 

activities. 

Figure 3 and Table 3 show the plotted means and ranges for 

each of the mean values of all 20 sampling locations 

averaged 1.02 x lo-l3 $.X./cc. This value ,is lower than the 

mean value observed for all samples collected for the previous year which averages 1.37 x low13 pCi/cc.* 

The highest observed mean value for a sampling location was 

3.60 x lo-l3 $j./cc in Area 16, Tunnel Pad, and the lowest 

was 1.89 x lo-14 @i/cc in the Area 1 Gravel Pit. 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 usually the result of a single high or low value. 

These extreme values did not drastically affect the mean 

values 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. Although 

2% of the total nt.Wer of air samples collected during 

this report period showed activity levels cmer backmund, 

a statistical summary of this data would not be meaningful 

-2- 
because of the uncertainty associated wit}! results uncorrected for self -absorption and the low activity values 

which result in a high relative ?a counting error. 

Routine gamma counting of all environmental air filters was 

initiated in February, 1$X'%. Tne ma,jcrity of air samples 

which were courted for gross gamma during this report period 

indicated levels less than background. Except for the 

sampling periods in November, 1966 and January, 1967, when 

all stations indicated the presence of short-iived gamma 

emitting radionuclides, all other isolated cases were associated with an individual test operation. Gamma spectrum and 

decay analyses of the samples in November and January indicated that their origin was from foreign weapons testing. 

In a.11 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. 

The observed mean of gross beta radioactivity for a total of' 

895 air samples collected this year was 1.02 x lC-l3 pCi/cc. 

F'or the same sampling period during the previous year, this 

value was 1.37 x lo-13 uCi/cc based upon a total of 613 air 

ssnlples collected from 14 location:; within the NTS. 

1 . :: Summary 

These results indicate, in general, a slight decrease in 

mean values since preceding periods. This may be attributed 

to a number of contributing variables: less intensive testing operations, fewer venting problems, more refined air 

volume measurements, more careful laboratory preparation 

methods, and better counting procedures. 

Results of environmental surveillance in sampling activity 

values obviously cannot be used in calculating personnel 

exposure doses. They are instead used as an index and in 

the detection of trends, and emphasis is either sustained 

or shifted to other sample Qypes whenever significant 

changes in levels are noted. 

*Staff report, "Environmental Radioactivity at the Nevada 

Test Site July, 1965 through June, 1966," NVO-162-25, 

Radiological Sciences Department, Reynolds Electrical & 

Engineering Co., Inc., November, 19%. 

-3- 
SECTTON 2 

Water Sampling 

2.1 Introduction 

Water samples were collected from selected waste ponds, reservoirs, sewage basins, natural springs, wells, and potable 

water sources, such as cafeterias, swimming pools, etc., on 

a "grab sampletl 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 water was collected near the inlet 

points of the reservoirs, while the natural spring water 

samples were "grab" samples obtained by dipping at the surface. 

2.3 Sample Preparation 

All water samples were analyzed for gross beta and tritium 

concentrations. A 15 ml aliquot was first taken from the 

original sample in a 'j dram plastic vial and submitted to 

the counting laboratory to be gamma counted. 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 

preparation laboratory, the samples were sent to the counting laboratory and counted for beta.. When indicated, oneliter samples of water are submitted for gamma spectrum 

analysis. 

2.4 Counting Procedures 

All routine environmental water samples were analyzed for 

beta radioactivity by gas proportional counting. The 

water samples were analyzed by a Beckman WIDERETA system 

equipped with an automatic sample changer. The efficiency, 

i.e., the ratio of observed counts to known disintegrations, 

on the WIDEBETA system, was 57% for beta. The average 

background count rate was 1.8 counts per minute for beta. 

The tritium analyses were performed using a Packard 

-4- 
Tri-Carb Liquid Scintillation Spectrometer 

ciency of 18% and an average background of 

minute. 

with an effi16 counts per 

2.5 Statistical Sr;unmary of Results for Water 

2.5.1 Potable Water Samples 

The statistical breakdown for potable water samples 

for fiscal year 1967 was based upon nine sampling \ 

locations (Table 4 and Figure 4), taken on a weekly 

basis. 

Table 5 and Figure 5, and Table 6 and Figure 6 give 

the means and ranges for gross beta activity from 

July, 1966 through June, 1967. The means ranged from 

2.66 x 10~~ 

1.65 x 1r8 

~~,Ci/cc recorded on January 8, 196'j' to 

+/cc recorded on September 18, 1966. 

The maximum value for the year was 5.67 x 10-T $X/cc 

recorded September 18, 1966, at the Area 20 Dispensary. 

The average mean for fiscal year 1967 was 3.77 x 10Bg 

$X./cc as co 

T 

red with the mean for fiscal year 1966 

of 6.29 x lo- $X./cc. The current year's value is 

smaller than that of last 

T 

ar and is also well below 

the RCG level of 1.0 x 10' $X./cc. This value is 

based on the guides listed in AEC Manual chapter 

0524. There was a total of three potable water samples collected during the year which were at or 

slightly exceeded the recommended guide level. 

2.5.2 Natural Springs Water Samples 

The term %atural springs" encompasses most of the 

naturally occurring spring-fed pools occurring within the NTS. Although these springs may be used infrequently as drinking water by some individuals, they 

are considered as a separate classification from 

potable water sources. Such water may also be used 

from time to time for such industrial purposes as 

watering roads, washing down equipnent, ami for 

mixing drilling mud. In an effort to adequately 

cover the Test Site, eight sampling locations have 

been selected (Figure 7 and Table 7). All of these 

stations were sampled once a month. 

Table 8 and Figure 8 show the means and ranges for 

gross beta activity over a twelve month period. The 

means ranged from 7.40 x 10-g C./cc recorded on 

"6 December 18, 1966, to 1.46 x 10' @i/cc recorded on 

March 19, 1967. The maximum value for the twelve 

-5- 
month period was 7.81 x 10 -8 $X/cc which was 

recorded on September 18, 1966, in Area 12, Gold 

Meadows Spring. The average me n for fiscal year 

1967 was computed at 1.27 x 10 -8 $X/cc which was 

higher than the aver ge mean for fiscal year 1966 

which was 1.02 x 10' 8 $Zi/cc. (Refer to footnote 

at the end of Section 1.) 

No natural springs water sample collected during 

fiscal year 1967 exceeded the RCG of 1.0 x lo-7 

\ @i/cc. However, it is noteworthy that the maximum 

sample value recorded for Gold Meadow Springs was 

in an area where there is a maximum potential for 

Test Site originated fallout due to venting, arxl 

also would be expected to collect the maximum fallout from foreign weapons testing since it is completely open to the atmosphere. 

2.5.3 Open Reservoir Water Samples 

Open reservoirs have been created throughout the NTS 

to furnish a ready supply of water for various industrial purposes. Twelve of these reservoirs have been 

selected as sampling locations (Figure 10 and Table 

10). All of these locations are routinely sampled 

once a month. 

Table 11 and Figure 11 give the means and ranges for 

gross beta activity over the twelve month period of 

fiscal year 1967. 

4.49 x 10-9 

The means ranged froma low of 

$X./cc recorded on September 18, 1966, 

to a high of 1.37 x log8 recorded on April 16, 1967. 

The maximum re orded value for this reporting period 

was 3.94 x 10' 8 @i/cc which was recorded in May of 

1967 at Groom Lake, Well 4 Reservoir. The average 

"9 

for fiscal year 1967 was cornpuked at 8.00 x 

10’ &i/cc which was lower t n the mean for fiscal 

3 year 1966 which was 1.02 x 10' $X./cc. 

All open reservoir water samples collected during 

fis al year 1967 were well below the RCG of 1.0 x 

10- 4 $X/cc. 

2.5.4 Supply Wells Water Samples 

Thirteen supply wells were sampled on the NTS during 

fiscal year 1967 (Figure 13 and Table 13). Water 

from these and other wells throughout the Test Site 

is used for a variety of purposes ranging from sanitary 

water supply to drillin@; md preparation. The criteria for selecting particular wells to be sampled was 

based not only upon their potential use for human 

-6- 
consumption but also upon their value as an index 

for measuring the possible movement of radioactive 

contamination in the aquifer. Most of these wells 

are located in areas where the movement of water 

in the aquifer is from known contaminated underground ,test sites. To date no data have been obtained that would indicate that the ground water at 

any well sampling location has been significantly 

affected by movement of contamination through the 

aquifer. 

Table 14 and Figure 14 give the means and ranges 

for gross beta activity over a ten month period 

from September, 1966 through June, 1967. Samples 

for July and August, 1966 were lost due to crosscontamination during laboratory analysis. The means 

of sample activity for the ten month period ranged 

from a low of 4.91 x 10-9 ~Ci/cc recorded on January 

5, 1967 to a high of 1.28 x lo-8 &i/cc recorded on 

April 9, 1967. The maximum sample value for the ten 

month period was 3.24 x 10-B jL!i/cc recorded on 

March 19, 1967 in Area 15, Well UelSd. The average 

mean for fiscal year 1967 was computed at 7.26 x 

10-9 Ki/cc which is substantially lower than the 

average mean of 1.02 x 10-B @i/cc for fiscal year 

19&L 

As was pointed out previously, all sample,values were 

well below any level of concern and did not exceed 

the RCG of 1.0 x 10e7 $X/cc. 

2.5.5 Final Effluent Water Samples 

Four locations were sampled (Table 16 and Figure 16) 

all in NTS living areas, to determine what, if any, 

levels of radioactitity were present in sewage. This 

program was initiated in October, 1966, and terminated 

in April, 1967. 

Figure 17 and.Table 17 give the means and ranges for 

gross beta activity over the seven month peri d. 

The means ranged from a minimum of 1.14 x 10' 8 $X/cc 

recorded in December, 1966, to a maximum of 2.77 x loo8 

$X./cc recorded in March, 1967. The 

!? 

ximum value for 

the seven month period was 5.55 x 10' $X/cc recorded 

in April, 1967, at the Groom Lake Sewage Pond. The 

average mean for the sampling period was computed to 

be 1.56 x lO-8 @i/cc. This value is well below the 

RCG of 1.0 x low7 @i/cc. 

2.5.6 Miscellaneous Water Samples 

There were six mixcellaneous water sampling locations 

-7- 
sampled during fiscal year 1967. Each location had 

some unique characteristics that removed it from the 

preceding groups, and, because of this, each location has been treated separately. 

The first two areas to be discussed are the Mercury 

s~&nming pool in Area 23 ana the Groom Lake Station 

2. Both 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 Station 2 at Groom -Lake is enclosed but dust 

from the outside can still be carried in and dispersed in the water. 

The next group of related sample locations comprises 

the permanent bodies of contaminated water located 

at the Control Point (CP) decontamination pad in Area 

6 and the Upper and Lower Haines Lakes in Area 12. 

The waste pond in 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 in E Tunnei in 1961 

and also in 1967. It has continued to discharge contaminated seepage water. Like the CP waste pond, 

these reservoirs are controlled radiation zones. 

Papoose Lake is the only natural drainage basin on the 

Test Site which is continually sampled. Any contamination which shows up there is the result of airborne 

surface material or atmospheric fallout from past atmospheric detonations. 

Table 19 gives the means and ranges for all six locations based on samples collected once a month over 

a twelve-month sampling period except for the CP 

waste pond'. This location was sampled on a quarterly 

basis only. 

-8- 
SECTION 3 

Background Radiation Measurements 

3.1 Introduction 

Background radiation measurements were obtained at weekly intervals from five sample locations. For a map of these locations see Figure 20. Methods and procedures followed were 

similar to those used in environmental surveillance programs 

at other atomic energy sites. The results are similar in 

that the ranges of values observed correlate well. 

3.2 Measurement Methods 

Background measurements were obtained using Victoreen Model 

239 indirect reading ionization chambers. Five of these 

chambers were located in a small semi-protective enclosure 

at each location. The locations chosen were in NTS living 

areas. This particular model instrument has an effective 

range of O-10 mR. 

As a back-up for the ionization chambers, standard NTS film 

dosimeters were also included in each sample location. It 

is possible that, should a test vent, high levels of radioactivity would be encountered beyond the range of the ionization chambers. Therefore, a higher range dose-measuring 

device was felt necessary. However, all results from these 

film dosimeters for the fiscal year 1967 were either zero or 

lost due to light or heat damage. (No venting problems 

occurred which would subject the sampling location to dose 

rates above the -30 mR minimum detection level of the 

film dosimeter.) 

In view of the extreme environmental conditions at the NTS 

which adversely affected the film dosimeter response, and 

since there are other measurement programs available to 

assess high dose rates from inadvertant venting problems, 

the use of film dosimeters has been discontinued. 

3.3 Analysis Procedures 

The ionization chambers were collected on a weekly basis and 

read on a Victoreen Minometer II reader. Corrections were 

made for background and for drift - non-radiation induced 

discharge of the chambers. Two sets of ,chambers were involved, one set being used at the sample locations for measurements and another set fully charged stored in the laboratory. Each week these sets were exchanged, the fresh set 

being recharged and a record kept of the amount of "drift" 

while stored in the laboratory. A specially designed shock 

proof box was used to transport the chambers to minimize 

accidental discharge due to mechanical shock. 

-9- 
Readings from the five chambers in each location were averaged to obtain a mean value for each location per week, 

hence the lack of ranges for observed values in the accompanying figures and tables. Readings from inc'ividual 

chambers which were grossly higher than the others at a 

particular location were not used in compiling the data 

since they most probably were the result of shock or other 

malfunctions and not representative measurements. 

3. 4 Measurement Results 

Thestatistical breakdown for the background measurements 

for fiscal year 1967 was based on five sample locations on 

a weekly basis (Table 20 and Figure 20). Individual sample 

location results are plotted in Figures 20 through 24. Results are tabulated in Table 21. 

The results presented in Table 21 reflect a reasonably 

stable ambient background for each of the sampling locations. 

Unusual fluctuations of the results were attributable to 

(1) foreign weapons tests, (2) NTS tests which vented, or 

(3) NRDS reactor runs which contrib.Aed measurable airborne 

contamination in some instances. 

Evaluation of these results indicates that no significant 

radiation hazard existed in the vicinity of the ion chamber 

locations during the fiscal year 1967. The average gamma 

radiation measurement for each of the sampling locations 

was less than 1 mR/day. 

-lO- 
TABLE1 

ENVIRONMENTAL SURVEILLANCE 

AIR SAMPLING STATION LOCATIONS 

MAP CODE 

AREA FOR FIGURE 1 

1 

2 

3“ 

5 

SAMPLF: STATION XXATION 

Gravel Pit la 

camp Compound 2a 

North of Cafeteria 3a 

;t 

West of Well 5B Reservoir 

Guard Station 250 

6 

9 

10 

11 

I.2 

16 

18 

Aid Station 6a 

9-300 Bunker 9a 

Guard Station 700 10a 

Guard Station 293 lla 

Changehouse l2a 

Tunnel Site Maintenance 16a 

East of Cafeteria 18a 

North of Airstrip l&b 

19 Echo Peak 

Stake lgC-10 

20 

23 

27 

28 

Groom Lab 

West of Aid Station 20a 

Building 214 23a 

West of Dispensary 27a 

Project- 28a 

East of Station 1 Groom Lake 

-ll- 
Groom Lake 

I 

b 

0 5. 

b 

IO Miles 

Fig. 1 NTS Environmental Surveillance Air Sampling Locations 

-12- 
SAMPLING PERIOD MEANS AND RANGES OF 

GROSS BEZ'A RADIOACTIVITY IN ENVIRONMENTAL. 

AIR SAMPLESFROMNTS 

JULY, 1966 THROUGHJUNE, 1967 

AIR SAMPLES (Values in terms of pCi/cc> 

IlAkE RANGE 

(Week ending) 

07/03/66 3.73 x 10-13 

07/10/66 1.55 x LO-13 

07/17/66 1.08 x lo-'-3 

07/24/66 1.50 x 10-13 

07/31/66 9.34 x 10-14 

08/07/66 6.81 x 10-14 

08/14/66 5.86 x 10-14 

08/21/66 9.18 x lo-14 

08/28/66 x lo-14 

09/0$/66 

6.91 

9.83 x lo-14 

09/n/66 5.95 x 10-14 

09/18/66 5.30 x 10-14 

09/25/66 5.74 x 10-14 

10/02/66 7.14 x 10-14 

10/09/66 6.81 x lo-14 

10/16/66 4.76 x lo-14 

10/23/66 4.36 x lo-14 

10/30/66 6.07 x lo-14 

n/06/66 7.24 x lo-l4 

n/13/66 2.36 x lo-12 

n/20/66 2.54 x lo-13 

11/27/66 7.60 x lo-14 

w/04/66 1.11 x 10-13 

12/u/66 7.65 x lo-14 

l2/18/66 4.41 x 10-14 

l-2/25/66 

01/01/67 

4.91 x 10-14 

7.43 x 10-14 

01/08/67 2.53 x 10-Q 

m/15/67 8.95 x lo-13 

01/22 167 8.55 x 10-13 

01/29/67 3.68 x lo-13 

02/05/67 x 10-13 

02/1-2/67 

2.79 

2.28 x 10-13 

02 /w/67 3.07 x 10-13 

02/26/67 1.59 x 10-13 

03/05/67 1.01 x 10-u 

03/u/67 2.31 x lo-13 

1.36 x 10-u 

1.92 x 10-13 

1.26 x 10.~3 

1.78 x 10-13 

1.20 x 10-13 

2.34 x 10-12 

9.27 x lo-l3 

1.48 x lo-l2 

1.08 x 10-u 

9.15 x 10-13 

8.89 x lo-13 

3.77 x 10-3-3 

7.48 x 10-13 

7.84 x 10-u 

1.16 x lo-12 

3.33 x 10-13 

3.55 x 10-13 

1.08 x lo-12 

1.53 x 10-B 

2.56 x lo-12 

1.01 x lo-l2 

6.33 x lo-13 

9.44 x 10-13 

1.57 x 10-D 

1.06 x lo-13 

1.05 x 10-13 

3.75 x 10-13 

1.08 x 10-11 

2.55 x lo-11 

1.54 x 10-u 

7.35 x 10-13 

8.00 x 10-13 

1.51 x 10-Q 

4.86 x lo-13 

3.70 x -10-13 

2.92 x 10-u 

3.37 x 10-13 

8.21 x lo-14 

8.46 x lo-14 

9.37 x 10-14 

1.25 x 10-13 

7.95 x 10-14 

1.36 x lo-14 

2.24 x 10-.14 

2.26 x lo-14 

2.16 x lo-14 

2.37 x 10;;; 

g-y: ; $14 

1:61 x lo-14 

2.12 x 10-14 

2.79 x 10-14 

1.12 x 10-14 

3.14 x 10-13 

1.69 x lo-13 

4.63 x lo-13 

2.11 x 10-13 

7.11 x 10-14 

4.20 x lo-14 

4.33 x 10-14 

1.77 x 10-14 

2.05 x 10-14 

1.55 x 10-13 

-13- 
TARLF: ? (Contd) 

AIR SAMPLES (Valucs.in terms of pCi/cc) 

DATE 

MEAN 

RANGE 

(Week ending) MAXIMUM MINIMUM 

w/w/67 

03/2%/67 

04/@/67 

04/w/67 

04/16/67 

04/23/&7 

04/30/67 

05/07/67 

05/14/67 

05/21/67 

05/28/67 

06/04/67 

06/n/67 

06/18/67 

06125167 

2.47 x lo-13 

1.75 x 10-13 

2.34 x lo-13 

1.82 x 10-13 

1.61 x 10-13 

1.14 x lo-13 

;*;z . x g-;; - 

9.32 x 10-14 

1.07 x 10-13 

5.64 x 10-14 

5.77 x 10-14 

1.13 x 10-13 

9.62 x lo-14 

4.09 x 10-14 

-14- 

1.19 x 10-12 

2.26 x 10-13 

3.01 x 10-13 

1.83 x 10-13 

6.55 x 10-13 

2.59 x 10-13 

1.05 x 10-13 

1.21 x 10-13 

6.44 x 10-13 

1.23 x 10-13 

7.32 x 10-14 

1.07 x 10-13 

3.05 x lo-l.2 

2.95 x lo-13 

7.83 x lo-14 

3.10 x 10-14 

1.31 x 10-13 

1.85 x 10-13 

8.63 x 10-14 

5.54 x 10-14 

7.31 x 10-14 

1.70 x 10-14 

4.52 x lo-14 

3.08 x lo-14 

2.83 x 10-14 

2.80 x 10-14 

1.01 x 10:;; 

;*g ; g-14 

2156 x lo-14 
1X16' 

\ 

l= 

JULY AUG SEPT OCT NOV DEC JAN FEE MAR APR MAY JUNE 

1966 1967 

Fig. 2 Weekly Means and Ranges of Gross Beta Radioactivity 

From July 1966 Through June 1967; Air Sampling 

-15- 
TABLE 3 * 

MEANS AND RANGES OF GROSS'BETA RADIOACTIVITY 

INNTS EWIRONMENTALAIR SAMPLING STATIONWCATIONS 

FROM JULY, 1966 THROUGH JUNE, 1967 

AIR SAMPLES (Values in terms of $X/cc) 

c 

\ 

RANGE 

STATION NUMBER 

AND LOCATION WMUM - 

1. Area 1 Gravel Pit 

2. Area 2 Compound 

3. Area 3 Cafeteria 

4. Area 5 Well 5B 

5. Area 5 Gate 250 

6. Area 6 Campsite 

7. Area g 9-300 Bunker 

8. Area 10 Gate 700 

9. Area 11 Gate 293 

10. Area 12 Changehouse 

11. Area 16 Tunnel PAD 

12. Area 18 Dispensary 

13. Area 18 Airstrip 

14. Area lg Echo Peak 

15. Area lg Stake 196-10 

16. Area 20 Dispensary 

17. Area 23 Building 214 

18. Area 27 Dispensary 

19. Area 28 HENRE Site 

20. Groom Lake, Station 1 

1.89 x 10 -14 2.28 x lo-l3 1.01 x 10 -14 

1.48 x lo-l3 3.39 x lo-l2 2.86 x 10”’ 

1.14 x lo-= 3.69 x 10 -12 1.01 x 10 -14 

7.47 x lo-l4 1.34 x 10 -12 1;61 x io-14 

6.49 x io -14 3.05 x 10 -12 1.31 x 10 -14 

9.89 x lo -14 3.25 x 10 -12 2.46 x lo -14 

6.19 x lo -14 3.01 x lo-l2 2.87 x io-14 

1.28 x lo-l3 3.05 x 10 -12 2.42 x lo -14 

3.61 x lo-l4 2.51 x lo-l2 1.12 x 10 -14 

1.10 x lo-l3 2.58 x lo-l2 2.12 x 10 -14 

3.60 x 10 -13 7.84 x lo-l2 2.68 x 10 -14 

1.06 x lo-l3 2.92 x lo-l2 1.46 x 10 -14 

6.81 x lo-l4 2.15 x 10 -12 1.36; x 10 -14 

2.17 x 10 -14 7.09 x lo-l2 1.91 x 10 -14 

7.01 x lo-l4 2.45 x lo-l2 2.66 x io -14 

1.11 x lo-l3 2.70 x 10 -12 1.45 x lo-l4 

8.60 x io-i4 1.41 x lo-l2 1.85 x lo-l4 

9.42 x lo-l4 2.62 x d2 2.87 x io -14 

1.55 x lo-l3 2.55 x 1O'll 2.56 x 10 -14 

1.12 x lo-l3 4.74 x 10 -12 2.03 x 1.0 -14 

-16- 
I T 

- 

- 

. 

I I 

- 

1x16’ 

1Xld’ 

Tt 

U 

t 

1x10-’ 

1X16’ 

- 

I 

- 

- 

- - - 

- 

, 

. 

. 

i 6 I 11 12 13 14 15 16 17 

SAMPLE STATION NUMBER 

Fig. 3 Means and Ranges of Gross Beta Radioactivity 

From July 1966 Through June 1967; Air Sampling 

-17- 
TABLE 4 

AREA 

2 

3 

6 

I2 

18 

20 

23 

27 

Groom Lake 

ENVIRONMENTAL SURVEILLANCE 

POTABLE :JATER SAMPLING STATTON LOCATIONS 

SAMPLING STATION LOCATION 

MAP CODE 

FOR FIGURE 4 

Men's Rest Room 2a 

Cafeteria 3a 

Cafeteria 

Cafeteria l2a 

Fire Station 18a 

Dispensary 20a 

Cafeteria 23a 

Cafeteria 

Station 1 

27a 

Groom T&e 

-18- 

-_/ -7 -‘- .,. .-------ir-------,~ 
\ \ SWI 

-\ 19 I ,- l Groom Lake 

II -- 15 

I 0 5 IO Miles 

Fia. 4 NTS Environmental Surveillance Potable Water Sampling Locttions 
TABLE 5 

MEANS AND RANGES OF GROSS BETA RADIOACTIVITY 

AT NTS ENVIRONMENTAL POTABLE WATER SAMPLING STATION LOCATIONS 

FROM JULY, 1966 THROUGH JUNE, 1967 

(Values in terms of uCi!cc) 

STATIBN NUMBER RANGE 

AND LOCATION MEAN MIixmKJM MAXIMUM 

1. Area 7 Men's Rest Room 3.80 x lo-9 

2. Area 3 Cafeteria 5.65 x 10-g 

3. Area d Cafeteria 6.79 x 10-9 

4. Area I.2 Cafeteria 3.12 x 10-9 

5. Area 18 Fire Station 1.87 x 10-9 

6. Area 20 Dispensary ' 2.63 x 10-9 

7. Area 23 Cafeteria 2.42 x 10-9 

a. Area 27 Cafeteria 2.61 x 10-9 

9. Groom Lake, Station 1 5.06 x 10-9 

-2o1.92 x 10-9 

2.52 x 10-9 

1.58 x 10-9 

1.58 x 10-9 

1.51 x 10'9 

1.59 x 10-9 

2.01 x 10-9 

1.50 x 10-g 

2.15 x 10-9 

-i. 38 x lo-9 

1.43 x 10-8 

4.44 x 10-8 

8.92 x 10-9 

7.28 x 10-9 

1.03 x 10-Y 

9.94 x 10-9 

6.94 x 10-9 

1.01 x 10-a 
1 2 3 4 5 6 7 8 

SAMPLE STATION NUMBER 

Fig, 5 Means and Ranges of Gross Beta Radioactivity at NTS Environmental 

Potable Water Sampling Locations From July 1966 !lYhrough June;' 1967 

-21- 
TABti 6 

MEANS AND RANGES OF GROSS BEl!A RADIOACTIUTY 

AT NTS ENVIRONMEXTAL POTABLE WATER SAMPLING STATION LOCATIONS 

FROM JULY, 1966 THROUGH JUNE, 1967 

(Values in terms of CcCiicc) 

DATE ' 

(Week ending) 

RANGE 

MAXIMUM MINIMUM 

07/03/t% 5.61 x 10-9 

07//10/66 5.19 x 10-9 

o7/17/66 5.43 x 10-9 

07/2 4/66 4.25 jc 10-9 

07,/31/66 1.21 x 10-8 

08 /o7/66 2.96 x 10-9 

o8/14/66 7.21 x 10-9 

08/21,46 3.66 x 10-9 

08/28!66 4.06 x 10-9 

09/04/66 3.38 x 10-9 

09/11/G 4.25 x 10-Y 

09/18/66 1.65 x lo-8 

09/25/G& 3.67 x 10-9 

10/m/66 4.33 x 10-9 

10/09/66 4.76 x 10-9 

10/16/G 3.75 x 10-9 

10/23/66 3.71 x 10-9 

10/30/66 3.42 x 10-9 

11/06/60 3.53 x 10-9 

n/13/66 3.42 x 10-9 

u/20/66 3.30 x 10-g 

u/27/66 3.46 x 10-g 

l2/04/'66 4.21 x lo-9 

12/n/66 3.37 x 10-9 

l2/18/66 3.58 x 10-9 

u/25/66 3.42 x 10-g 

ox/n/67 4.74 x 10-9 

a/08/67 2.66 x 10-9 

01/15/67 3.42 x 10-9 

01/22/67 3.80 x 10-9 

ol/29/67 4.02 x 10-9 

02/05/67 .3.88 x 10-9 

02/1.2/67 x 10-9 

02/19/67 

3. :;': 

5.29 x 10-9 

02/26/67 3.29 x 10-9 

o3/o5/67 5.05 x 10-9 

o3/l2/67 4.10 x 10-9 

o3/19/67 6.42 x 10-9 

-22- 

9.94 x 10-9 

8.36 x 10-9 

8.15 x lo-? 

~8.68 x 10-9 

1.03 x 10-7 

5.42 x 10-9 

4;44 x 10-a 

g.;g x 

7:29 x" 

u$-; 

10-9 

6.05 x 10-9 

5.67 x 10-7 

6.37 x 10-9 

7.46 x 10-9, 

1.01 x 10-8 

6.53 x 10-9 

6,64 x 10-9 

6.19 x 10-9 

7.13 x 

;:g :: 

101; 

gj-9 

7.15 x 10-9 

a.60 x 10-9 

4.89 x 10-9 

7.11 x 10-9 

5.65 x 10-9 

6.20 x 10-9 

4.91 x 10-g 

7.28 x 10-9 

7.70 x 10-9 

6.80 x 10-9 

8.90 x 10-9 

5.45 x 10-9 

7.84 x 10-9 

7.21 x 10-9 

j.28 x 10-9 

5.58 x 10-9 

1.96 x 10-a 

2.50 x lo-9 

2.58 x 10-9 

2.58 x 10-9 

1.58 x 10-9 

2.93 x 10-9 

1.59 x 10-9 

2.20 x 10-9 

1.50 x 10-9 

1.68 x 10-9 

2.33 x 10'9 

2.70 x 10-9 

l.j2 x 10-9 

1.88 x x-3 

2.40 x 10-9 

1.69 x 10-9 

2.50 x 10-9 

2.16 x 10-9 

2.27 x 10-9 

2.28 x 10-9 

2.38 x lo-9 

2.56 x 10-9 

1.85 x 10-9 

2.24 x 1O-9 

2.57 x 10-9 

1.58 x 10-9 

2..04 x 10-9 

3.73 x 10-9 

2.15 x lo-9 

3.05 x lO"9 

1.63 x 10-9 

2.02 x 10-9 

2.36 x 10-9 

2.29 x 10-9 

2.18 x 10-9 

2.07 x 10-3 

3.69 x 10-9 

1.92 x 10-9 

3.57 x 10-9 
TABLE 6 (Contd) 

POTABLE WATER SAMPLES (Values in terms of !.fCi/cc) 

DATE RANGE 

(Week ending) MAXIMUM MINIMUM 

o3/26/67 

04/e/65 

o4/o9/67 

04/16/67 

04/23/67 

o4/3o/67 

o5/o7/67 

o5/14/67 

o5/21/67 

05/28/67 

06/04/67 

06/n/67 

06/18/67 

o6/25/67 

5.77 x 10-9 

6.66 x 10-9 

5.22 x 10-9 

5.15 x 10-9 

4.75 x 10-9 

6.10 x 10-9 

y; 

3182 

; g-; 

x 10-9 

4.16 x 10-9 

3.32 x 10-9 

4.11 x 10-9 

3.63 x 10-9 

4.91 x 10-9 

1.21 x 10-8 

1.42 x 10-8 

1.06 x lo-8 

1.01 x 10-8 

1.02 x 10-8 

9.14 x 10-g 

1.59 x 10-8 

1.01 x 10-B 

1.09 x 10-8 

1.08 x 10-a 

7.24 x 10-9 

1.18 x lo-8 

1.31 x 10-8 

1.11 x 10-a 

2.49 x 10-g 

2.86 x 10-9 

3.38 x 10-9 

1.88 x 10-9 

2.09 x 10-9 

3.90 x 10-9 

4.16 x 10-9 

1.78 x 10-9 

1.51 x 10-9 

1.59 x 10-9 

1.50 x 10-9 

2.07 x 10-9 

1.83 x 10-9 

1.82 x 10-9 

-a- 
1x10-: 

1x10’ 

< 

is 

a 

1x10-’ 

- 1 

. B 

1966 

JAN FEB MAR APR 

1967 

MAY J UNE 

Fig. 6 Weekly Means and Ranges of Gross Beta Radioactivity in Potable Water 

Samples From July l$G Through June 1967 

-24- 
TABLE 7 

ENVIRONMENTAL SURVEILLANCE 

NATURAL SPRING SAME'LING STATION LOCATIONS 

AREA 

5. 

12- 

15 

16 Tippipah Spring 16a 

SAMPLE STATION LOCATION 

Cane Springs 

Captain Jack Spring tia 

White Rock Spring l2b 

Gold Meadows l2C 

Oak Spring 15a 

Tub Spring 1% 

John's Spring 15c 

MAP CODE 

FOR FIGURE 7 

5a 

-25 
Groom Lake 

~ 

30' 

-- 

I 

I --l 

I 

29' 

-- -- 1 

I-- L,-- - 

A- MERCURY 

I 0 5 IO Miles 

Fig. 7 NTS Environmental Surveillance Natural Springs Sampling Locations 
TABLE 8 

MONTHLY MEANS AND RANGES OF GROSS BETA RADIOACTIVITY 

AT NTS NATURAL SPRING SAMPLING STATION LOCATIONS 

FROM JULY, 1966 THROUGH JUNE, 1967 

DATE 

(Week ending) 

07-17-66 

08/14/66 

(Values in terms of &i/cc) 

RANGE 

I-+!AxrMuM MrNrMuM 

9.62 x 10-9 2.29 x lo-8 4.46 x 10-9 

1.13 x 10-8 1.52 x 10-8 5.47 i 10-9 

og/18/66 9.93 x 10-9 7.81 x 10-8 1.53 x 10-9 

10/16/66 9.48 x 10-9 6.80 x 10-8 2.33 x 10-9 

11/20/66 9.75 x 10-9 6.83 x 10 -8 3.77 x 10-9 

l2/18/66 7.40 x 10-9 1.68 x 1C8 -1.61 x 10-9 

01/15/67 1.06 x 10-8 3.27 x 10-a 4.56 x lo-9 

02 /w/67 1.10 x 10-B 1.24 x 1O-8 4.33 x 10-9 

w/w/67 1.46 x 10-8 6.24 x lo-8 2.68 x lo-9 

04/16/67 1.43 x 10-8 6.99 x lo -8 5.43 x 10-9 

05/14/67 1.37 x 10-8 6.13 x IO-~ 4.48 x lo-9 

06/u/67 1.35 x 10-8 4.14 x 10-8 5.52 x 10-g 

-27- 
lxd 

1x10" 

1x10"' 

Y 1 ” 0 . C N 3 I MAY J 

Fig. 8 Monthly Means and Ranges of Gross Beta Radioactivity in Natural 

Springs Water Samples From July 1966 Through June 1967 

-28- 
TABLE 9 

MEANS AND RANGES OF GROSS BETA RADIOACTIVITY 

AT NTS ENVIRONMENTAL NATURAL SPRING SAMPLING STATION LOCATIONS 

FROM JULY, 1966 THROUGH JUNE, 1967 

(Values in terms of &i/cc) 

STATION NUMBER RANGE 

AND LOCATION MAXIMUM MINIMUM 

1. 

2. 

3. 

4. 

5. 

6. 

7. 

8. 

Area 5, Cane Spring 

Area 12, White Rock 

Spring 

Area 12, Captain Jack 

Spring 

Area 12, Gold Meadow 

Spring 

Area 15, Oak Butte 

Spring 

Area 15, Tub Spring 

Area 15, John's Spring 

Area 16, Tippipah 

Spring 

7.21 x 10-9 

1.23 x 10-8 

7.22 x lo-9 

4.85 x 10 -8 

6.33 x 10-9 

6.57 x 10-9 

6.39 x lo-9 

7.05 x 10-9 

1.60 x lo-8 1.53 x 10-9 

2.29 x 10-8 8.96 x lo-9 

1.16 x IO-~ 1.61 x 10-g 

7.81 x IO-~ 2.29 x 10-8 

1.33 x 10-8 4.30 x 10-9 

1.23 x loo8 3.73 x 10-9 

2.61 x lo-8 2.33 x 10-9 

1.40 x 10-8 2.43 x lo-9 

-2g- 
1x16 

1x10’ 

-t 

u 

a 

1x10- 

1x10-l 

-- 

3 4 5 6 7 9 10 11 12 13 

SAMPLE STATION NUMBER 

- 

Fig. 9 Means and Ranges of Gross Beta Radioactivity From July 1966 Through 

June 1967; Natural Springs Sampling Locations 

-3o- 
TABLJZ 10 

ENVIRONMENTALSURVEILLANCE 

OPEN RESERVOIR SAMPLING STATION LOkATIONS 

AREA SAMPLING STATION LOCATION 

MAP CODE 

FOR FIGURE 10 

2 Well2 Reservoir \ 

3 \ 

5 

6 Well Cl Reservoir 

15 

17 

18 

19 

20 Well U2Oa Reservoir 

Groom Lake Well 4 Reservoir 

Well "A" Reservoir 

Well 5B Reservoir 

Well Ue5c Reservoir 

Well Uel5d Reservoir 

Well 1 Reservoir 

Camp 17 Reservoir 

Well Uelge Reservoir 19a 

Well Uel9gs Reservoir 19 

2a 

3a 

:b” 

6a 

158 

17a 

18a 

20a 

GroomLake 

-31- 
\ 

\Y 

I \ t 

\ 3n I \ 

0 

Groom La; 

MESA I- --i 0150 / I 

ke 

m 

29 I \-1 . . -0- 

, \ 

I 

c I 

0 5 IO Miles 

Fig. 10 NTS Environmental Surveillance Qpen Reservoirs Sampling Locations 

-32- 
TABLE 11 

MONTHLY MEANS AND RANGES OF GROSS BCTA RADIOACTIVITY 

AT NTS OPEN RESERVOIR WATER SAMPLING STATION LOCATIONS 

FROM JULY, 1966 THROUGH JUNE, 1967 

(Values in terms of MCI/cc) 

DATE 

(Week ending) 

RANGE 

MAXIMUM MINIMUM 

07-10-66 8.84 x 10-9 1.34 x 10-8 4.67 x 10-9 

08-07-66 8.15 x lo-9 1.15 x 10-B 2.62 x 10-9 

09-18-66 4.49 x 10-9 8.75 x 10-9 2.24 x 10-9 

10-16-66 7.88 x 10-9 2.88 x lo-8 2.44 x lo-9 

11-13-66 4.94 x 10-9 1.19 x 10-B 1.99 x 10-g 

12-11-66 5.52 x 10-9 2.26 x lo-8 2.19 x 10-g 

01-15-67 6.80 x 10-9 1.44 x 10-B 1.78 x 10-g 

02-12-67 7.09 x 10-9 1.05 x 10-B 2.19 x 10-9 

03-12-67 5.78 x 10-9 1.69 x lo-8 1.79 x 10-g 

04-16-67 1.37 x 10-B 3.94 x 10 -8 4.85 x 10-9 

05-07-67 1.28 x lo-8 3.94 x 10-8 4.41 x 10-g 

06-11-67 9.9 x 10-g 1.88 x 10-8 2.18 x lo-9 

-33- 
lxlo1x10 

2 

U 

3 

1x10‘ 

1x10" 

J Y 1 ‘T 

1966 

N 3 I R 

196i 

R MAY JUNE 

Fig. 11 Monthly Means and Ranges of Gross Beta Radioactivity in 0-n 

Reservoir Water Samples From July 1966 Through June 1967 
TABLE: I2 

MEANS AND RANGES OF GROSS BEX'A RADIOACTIVITY 

AT NTS ENVIRONMENTALOPENRESERVOIR SAMPLING LOCATIONS 

FROM JULY, 1966 THROUGH JUNE, 1967 

I 

(Values in terms of @i/cc) 

STATION NUMBER RANGE 

AND LOCATION MAXIMUM MINIMUM 

1. 

2. 

3. 

4. 

5. 

6. 

7. 

8. 

9. 

10. 

11. 

12. 

13. 

Area 2, Well 2 

Reservoir 

Area 3, Well A 

Reservoir 

Area 5, Well 5B 

Reservoir 

Area 5, WellUe5c 

Reservoir 

Area 6, Well 3 

Reservoir 

Area 6, Well Cl 

Reservoir 

Area 15, WellUel5d 

Reservoir 

Area 17, Well 1 

Reservoir 

Area 18, Camp 17 

Reservoir 

Area 18, Well 8 

Reservoir 

Area 19, WellUel% 

Reservoir 

Area 20, Well U2Oa 

Reservoir 

Groom Lake, Well 4 

Reservoir 

5.51 x 10-9 

9.76 x 10-9 

7.71 x 10-9 

5.32 x 10-9 

8.63 x lo-9 

1.21 x 10-8 

1.12 x 10-8 

5.66 x 10-9 

2.45 x 10-9 

5.33 x 10-9 

3.43 x 10-g 

3.53 x 10-9 

2.38 x lo-8 

-35- 

1.53 x 10-8 2.19 x 10-g 

1.94 x 10-8 3.28 x 10-9 

1.35 x 10-8 2.58 x 10-9 

8.77 x 10-9 3.08 x lo-9 

2.88 x lo-8 3.58 x 10-9 

2.26 x IO-~ 7.15 x 10-9 

2.12 x 10-8 1.79 x 10-g 

2.86 x lo-8 2.36 x 10-9 

1.02 x 10-8 1.78 x 10-9 

8.77 x lo-9 4.64 x 10-9 

5.19 x 10-9 2.18 x lo-9 

5.42 x 10-9 1.99 x 10-g 

3.94 x 10-8 1.53 x LO-8 
1x10-; 

1x10” 

lxlo-‘t 

1 2 3 4 6 7 

SAMPLE STATION NUMBER 

10 11 12 13 

Fig. 12 Means and Ranges of Gross Beta Radioactivity From July 1966 

Through June 1967; Open Reservoir Sampling 
TABLE 13 

ENVlRONMENTALSURVFJLLANCE 

SUPPLY WELLS SAMPLING STATION LOCATIONS 

AREA 

3 

5 

MAP CODE 

SAMPLING STATION LOCATION FOR FIGURE 13 

Well A 3a. 

Well 5A 

Well 5B 

Well 5C 

Well UefSc 

5a 

; 

5d 

6 

15 

17 

19 

Well Cl 6a 

Well UelSd- i5a 

Well 1 17a 

Well Uelggs 

Well Uel* 

20 

22 

Well U2Oa 20a 

Army Well #l 22a 

GroomLake Well 3 Groom Lake 

Groom Lake Well 4 Groom Lake 
J, ..r*. I 

I 

-....* 

l l9b 

I 

0 

- Groom Lake 

I . I / I i I I 

I 0 5 IO Miles 

fig. 13 NTS Environmental Surveillance Supply Wells Sampling Locations 

-sv 
TABLE 14 

MONTHLY MEANS AND RANGES OF GROSS BETA RADIOACTIVITY 

IN NTS SUPPLY WELLS WATER SAMPLES 

FROM JULY, 1966 THROUGH JUNE, 1967 

(Values in terms of @i/cc) 

(Week ending) 

RANGE 

MAXIMUM MINIMUM 

July No Data 

August No Data 

og/li/66 9.07 x 10-g 

10/16/66 6.43 x 10-g 

1.29 x 10-8 6.33 x 10-g 

1.41 x 10-8 1.64 x 10-g 

u/20/66 4.97 x 10-g 1.12 x 10-B 2.49 x 10-g 

l2/18/66 6.97 x 10-g 1.22 x 10-8 4.00 x 10-g 

ol/l5/67 4.91 x 10-9 2.48 x 10-8 1.56 x 10-g 

Wig/W 6.58 x 10-9 1.79 x 10-B 3.20 x lo-9 

a/w/N 1.10 x 10-8 $24 x 10-8 3.04 x 10-9 

04/w/67 1.28 x lo-8 3.23 x 10 -8 6.41 x lo-9 

o5/o7/67 9.82 x lo-9 2.20 x 10-8 3.58 x lo-9 

06/u/67 7.33 x 10-g x.69 x lo-8 3.81 x 10-9 

-3% 
lxlo1xld 

1X10-" 

-- 

JULY A 

Fig.' 14 

G T 

1966 

J I N FEB 1 R 

196; 

R 

Monthly Means and Ranges of Gross Beta Radioactivity From 

September 1966 Through June 1957; Supply Wells Sampling 

-4o- 

----,-. :- __ --.-, ,, -, 
TABLE 15 

MEANS AND RANGES OF GROSS BETA RADIOACTIVITY 

AT NTS ENvlRONMEiNTAL SUPPLY WELLS SAMPLING LOCATIONS 

FROM JULY, 1966 THROUGH JUNE, 1967 

(Values in terms of &!i/cc) 

STATION NUMBER RANGE 

AND LOCATION MEAN MAXIMUM MINIMIM 

1. 

2. 

3. 

4. 

5. 

6. 

7. 

8. 

9. 

10. 

11. 

12. 

13. 

Area 3, Well A 

Area 5, Well 5A 

Area 5, Well 5B 

Area 5, Well 5C 

Area 5, WellUe5c 

Area 6, Well Cl 

Area 15, Well Uel5d 

Area 17, Well 1. 

Area 19, Well Uel9e 

Area 20, Well U20a 

Area 23, Army Well #1 

,?room Lake, Well 3 

Groom Lake, Well 4 

8.02 x lo-9 1.45 x 10-8 5.51 x 10-g 

7.32 x 10-g 1.06 x lo-8 4.72 x lo-9 

7.11 x 10-g 1.15 x 10-8 3.58 x lo-9 

5.99 x 10-9 1.10 x 10-8 4.14 x 10-9 

6.59 x 10-g 8.06 x 10-g 4.7l x 10-g 

1.05 x 10-8 2.15 x 10-B 3.82 x 10-9 

1.75 x 10-8 3.24 x lo-8 6.85 x 10-g 

2.86 x lo-9 4.98 x lo-9 1.64 x lo-9 

2.83 x lo-9 3.04 x 10-g 2.63 x lo-9 

2.58 x 10-9 2.67 x lo-9 2.49 x 10-g 

6.04 x lo-9 9.49 x 10-9 3.20 x 10-g 

5.26 x lo-9 1.10 x 10-8 2.60. x lo-9 

1.18 x IO-~ 2.20 x'io-8 2.68 x lo-9 

-419 
1x16 

1x10-’ 

1x10”’ 

1 

. 

- 

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

SAMPLE STATION NUMBER 

Fig. 15 Means and Ranges of Gross Beta Radioactivity From July 1966 

Through June 1967; Supply Wells Sampling 

-42- 
TABLE 16 

ENVIRONMENTAL SURVEILLANCE 

FINAL EFFLUENT STATION LOCATIONS 

MAP CODE 

AREA SAMPLING STATION IXATION FOR FIGURE 16 

6 Final Effluent Pond 6a 

I2 Final Effluent Pond l2a \ 

23 

Groom Lake 

Final Effluent Pond 

Pond 

23a 

Groom Lake 

-43- 
A. 

PJ 

I 

0 

Groom Lake 

IO’ 

-0 kL 9 

-0 

. 

.:A MERCURY 

I 

c I 

0 5 IQ Miles 

Fig. 16 NTS Environmental Surveillance Final Effluent Sampling Locations 

-44- 
TABLE17 

MONTHLY MEANS AND RANGES OF GROSS BETA RADIOACTIVITY 

l3ENVlRONMENTALFINALEF'FLUENTSAME'LES 

FROM OCTOBER, 1966 THROUGH APRIL, 1967 

(Values in terms of &i/cc) 

DATE MAXIMUM MINIMUM 

October, 1966 1.31 x 10-8 1.87 x lo-8 1.05 x 10-8 

November, 1966 1.63 x lo-8 1.09 x 10-8 7.43 x 10-9 

December, 1966 1.14 x 10-B 1.84 x lo-8 5.96 x 10-9 

January, 1967 1.45 x 10-8 1.81 x lo-8 1.17 x 10-8 

February, 1967 1.53 x 10-8 4.77 x 10-8 5.96 x 10-g 

March, 1967 2.77 x 1O-8 4.69 x lo-8 1.77 x 10-8 

April, 1967 1.92 x 10-8 5.55 x 10-8 1.00 x 10-8 

-45- 
lxlo1x10" I 

1966 

: J 

Fig. 17 Means and Ranges of Gross Beta Radioactivity From October 1966 

Through April 1967; Final Effluent Sampling 

-46- 
TABLE 18 

MEANS AND RANGES OF GROSS BETA RADIOACTIVl3!Y 

AT NTS ENVIRONMENTAL FINAL EFFWENT SAMPLING STATION LOCATIONS 

FROM OCTOBER, 1966 THROUGH APRIL, ig67 

(Values in terms of &i/cc) 

STATION. NUMBER RANGE 

AND LOCATION MAXIMUM MINIMUM 

1. Area 6, Sewage Pond 1.63 x lo-8 2.29 x 10-8 1.23 x io-8 

2. Area 12, Sewage Pond 1.77 x 10-8 4.77 x 10-8 1.00 x 10-8 

3. Area 23, Sewage Pond 9.59 x 10-g 1.77 x 10-8 5.86 x lo-9 

4. Groom Lake, Sewage 1.89 x lo-8 5.55 x 10 -8 1.09 x 10-8 

Pond 

-47. 
1x10-; 

1x10‘; 

1x10” 

1x10-” - 

3 3 4 5 6 7 8 

SAMPLE STATION NUMBER 

10 

A 

11 12 13 

Fig. 18 Means 'and Ranges of Gross Beta Radioactivity From October 1966 

Through April 1967; Final Effluent Sampling 

-48- 
TABLE 19 

MJUJJS AND RANGES OF GROSS BETA RADIOACTIVITY 

AT NTS MISCELLANEOUS SAMPLING LOCATIONS 

FROM JULY, 1966 THROUGH JUNE, 1967 

(Values in terms of ctCi/cc) 

SAJ$PLlJ'JG RANGE 

LOCATION MAXIMUM MINIMUM 

1. Area 51, Papoose Lake 7:54 x 10-8 

2. Area 6, CP-2 Waste Pond 4.62 x ld 

3. Area 12, Upper Haines 

Lake 4.32 x 10-6 

4. Area 12, Lower Haines 

Lake 1.98 x lo-6 

5. Area 23, Swimming Pool 5.87 x 10-9 

6. Groom Lake, Station 2 7.23 x 10-9 

5.00 x 10'7 

3.21 x lo-5 

4.74 x 10-5 

3.65 x lo-6 

1.22 x 10-8 

2.43 x lO-8 

2.13 x 10 -8 

4.89 x 10'7 

9.58 x 10-7 

8.54 x 10-7 

3.91x 10-9 

2.95 x 10-9 

-49- 
I-- 

Groom Lake 

A. 

+ 

I 

i/ 1 MERCURY 

IO Miles 

Fig. 19 NTS Environmental Surveillance Miscellaneous Water Sampling Locations 

-5o- 
TABLE20 

EXVIRONMEWML SURVEILLANCE 

IONIZATION CHAMBER SAMPLING STATION LOCATIONS 

MAP CODE 

AREA SAMPLING STATION LOCATION FOR FIGURE 20 

3 North of Cafeteria 3a 

6 North of Icehouse 6a 

I2 

23 

East of Dispensary 

South of Dispensary 

l2a 

23a 

27 Security Station 561 27a 

-51- 
Groom 

1 

Lake 

iMAN 

8 

IO Miles 

Fig. 20 Environmental Surveillance Ionization Chamber 

Sampling Locations 

-52- 
TABLE 21 

SUMMARY OF BACKGROUND RADIATION MF&%REMENTS (&?/day) 

DATE mm3 AREAS- AREA I2 AREA 23 mu 27 

North of West of South of South of 

(Week Ending) Cafe Icehouse Camp Dispensary Gate 561 REMARKS 

07/03/66 

07/10/66 

07/17/66 

07/24/66 

07/31/66 

08/07/66 

08/l4/66 

08/21/66 

08/28/66 

09/04/66 

09/n/66 

09/18/66 

09/25/66 

10/02/66 

10/09/66 

10/16/66 

10/23/66 

10/30/66 

11/06/66 

11/13/66 

11/20/66 

11/27/66 

u/04/66 

12/n/66 

l2/18/66 

W25/66 

01/01/67 

01/08/67 

Ol/l5/67 

01/22/67 

m/29/67 

02/05/67 

w/12/67 

02/19/67 

02/26/67 

03/05/67 

03/12/67 

03/l9/67 

03/26/67 

@+/of?/@ 

04/09/67 

04/l6/67 

04/23/67 

0.86 

. 1.09 

1.26 

0.85 

0.85 

0.79 

0.91 

0.76 

0.73 

1.23 

0.7-l 

1.20 

0.93 

0.75 

0.69 

0.82 

0.72 

0.70 

0.73 

1.17 

0.75 

0.92 

0.76 

0.95 

0.67 

0.76 

0.70 

0.93 

0.74 

0.81 

a.43 

0.62 

0.70 

0.98 

x 

1104 

1.19 

0.74 

a.43 

0.73 

1.04 

0.64 

0.36 a.43 

0.49 a.43 

0.39 0.64 

0.37 0.40 

0.58 0.49 

0.52 0.47 

0.54 0.53 

0.44 0.39 

0.44 0.49 

0.57 0.46 

0.74 0.47 

0.45 0.47 

0.44 0.48 

0.52 0.46 

0.46 0.48 

0.53 0.46 

0.97 0.58 

0.30 0.40 

0.54 0.51 

0.63 0.49 

0.42 0.51 

0.56 0.47 

0.39 0.52 

0.44 0.49 

0.56 _ 0.48 

0.58 0.47 

0.53 0.54 

0.75 0.58 

0.71 0.58 

1.08 0.51 

a.43 >l. 43 

0.51 0.39 

0.80 0.52 

0.60 0.48 

0.79 0.50 

0.49 0.59 

0.45 0.54 

0.54 0.50 

0.38 0.49 

0.33 0.48 

0.41 0.51 

0.43 0.48 

0.37 0.53 

0.35 

0.37 

0.39 

0.30 

0.31 

0.31 

0.34 

0.30 

0.39 

0.37 

0.31 

0.39 

0.33 

0.30 

0.36 

0.30 

0.43' 

0.28 

0.37 

0.38 

0.31 

0.36 

0.35 

0.50 

0.34 

0.37 

kt$ 

0.43 

0.42 

0.56 

0.30 

0.40 

0.46 

0.38 

0.35 

0.46 

0.64 

0.37 

0.48 

0.50 

0.44 

0.49 

0.44 NRX 

0.50 

0.46 

0.40 

0.42 

0.41 

0.43 

0.44 

0.43 

0.54 

0.42 

0.45 Area 5 

0.42 

0.45 

0.46 

0.48 

0.49 

0.42 

0.44 

0.49 

0.50 

0.47 

0.51 

0.52 

0.46 

0.50 

0.48 

0.52 

0.54 

0.47 

0.64 Area 2 

0.42 

0.54 

0.46 

0.47 Phoebus Run 

0.44 

0.50 

0.46 

0.46 

0.49 

0.47 

0.45 

0.35 ’ 
TABLE 21 (Contd) 

SUMMARY UF BACKGROUND RADIATION MEASUREMENT S (~/day> 

DATE mm3 AREA6 AREA12 AREA 23 AREA 27 

North of West of South of South of 

(Week Ending)' Cafe Icehouse C-P Dispensary Gate 561 REMARKS 

o4/3o/67 1.01 0.37 0.45 

o5/o7/67 0.73 0.33 0.52 

o5/14/67 0.89 0.37 0.41 

05/a/67 0.66 0.49 1.04 

o5/28/67 0.78 0.45 0.38 

06/04/67 0.64 0.28 0.47 

06/n/67 1.39 0.39 0.43 

06/18/67 0.74 0.51 0.79 

o6/25/67 0.74 0.46 0.44 

0.39 o.iF8 

0.42 0.45 

0.31 1.00 

0.91 0.60 

0.26 0.40 

0.29 0.45 

0.38 0.50 

0.33 0.44 

0.34 0.46 
i l 

I í 

lI I 

. 

c-u 

M 

b 
0 

5 

P 

7 

a 

Z 

e 
I 

-0 

a 

-t 

.e -2 7 

l 

I I I I 1 I I I 

,: 

0 

nap 

-5% 
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: 

x = log -1 

[ 

pi xi + g 1 

when: Xi = observed value 

E2 1 number of observations 

L - 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 = 

% -Rb 

A BC 

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

Rb = background count rate, c/m 

A = counting efficiency for a particular 

counter (cpm/dpm) 

B = conversio factor (2.22 dpm / pCi or 

2.22 x 10 2l dpm / ErCi) 

C = subsample amount, cc, liter, or gram 

-6o- 

,,., 
The associated percent counting error at the 2-sigma confidence level ($E2, > for each radioactivity value (X) was: 

where: Z = 2, the number of standard deviations for the confidence interval (95.4%) 

TS = sample count interval, minutes 

Tb = background count interval, minutes 

The radioactivity of a sample was considered statistically 

significant if the net count rate of the sample was greater 

than the detection limit, i.e., two times the net count for 

which the 2-sigma error was 100 percent. 

The detection limit was computed by 

PZ 

DL = 

ABC 

formula: 

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. 

-617 
DISTRIBUTION 

M. B. Biles, Director, DOS, AEC/HQ 

Major General F. A. Camm, AGM/MA/HQ 

R. J. Catlin, DEA, AECfiQ 

USAEC, TIC, Oak Ridge, TN (2) 

M. E. Gates, Manager, AEC/%V 

R. H. Thalgott, Scientific Advisor to the Manager, AEC/NV 

E. M. Douthett, Director, OEE, AEC/NV 

D. T. Schueler, Jr., Director, NTSSO 

A. J. Whitman, Acting Director, Radiological Operations Division, AEC/'NV 

R. R. Loux, TIB/OIS, AEC#V 

USAEC, NV Technical Library, Las Vegas, NV (2) 

D. S. Barth, Dr., Director, EPA/&RC, Las Vegas, NV 

D. W. Hendricks, Assistant Director for Radiological Operations, 

EPA-NERC/LV 

H. F. Mueller, Chief, NOAA/ARL, Lss Vegas; NV 

G. E. Tucker, Sandia Laboratories, Albuquerque, NM 

J. E. Dummer, I&L, Los Alamos, NM 

K. M. Oswald, LLL, Mercury, NV 

Librarian, EG&G, Las Vegas, NV (2) 

REECo Technical Library, Mercury, NV (2) 

Environmental Sciences, REECo, Mercury, NV (10)