SEPA
United States Eastern Environmental EPA 520/5-87-010
Environmental Protection Radiation Facility June 1987
Agency 1890 Federal Drive
Office of Radiation Programs Montgomery, AL 36109
Radiation
Radiological Survey of the
Pearl Harbor Naval Shipyard
and Environs, Honolulu,
Hawaii
-------
EPA 520/5-87-010
Radiological Survey
of the
Pearl Harbor Naval Shipyard and Environs
Honolulu, Hawaii
Robert S. Call is
U.S. Environmental Protection Agency
Office of Radiation Programs
Eastern Environmental Radiation Facility
1890 Federal Drive
Montgomery, AL 36109
-------
TABLE OF CONTENTS
Page
List of Figures v
List of Tables vii
Preface ix
Introduction 1
Characteristics of Pearl Harbor Naval Shipyard 2
Survey and Analytical Methods 6
Results and Discussion 8
Observations and Conclusions 11
References 22
m
-------
LIST OF FIGURES
Figure Page
1 General Area 3
2 Sampling Sites - Shipyard and Submarine Base 4
3 Sampling Sites - Other 5
-------
LIST OF TABLES
Tab 1e Page
1 Results of Harbor Water Analysis 12
2 Drinking Water Samples 13
3 Results of Aquatic Life Sample Gamma Analysis 14
4 Overland Exposure Measurements 15
5 Exposure Measurements Observed at Sampling Sites 16
6 Results of Aquatic Vegetation Analysis 17
7 Cobalt-60 Concentrations in Pearl Harbor Sediments
Collected during 1985, 1968, and 1966 Surveys 18
8 Sediment Core Samples - Cobalt-60 as a Function of
Depth Below Surface 21
VII
-------
PREFACE
The Office of Radiation Programs (ORP) identifies and evaluates
environmental public health impacts of both natural and man-made radiation
sources. The Eastern Environmental Radiation Facility (EERF) is a fully
integrated participant with other components of the Office in these efforts.
The Facility provides comprehensive capability for evaluating radiation
sources through planning and conducting environmental studies, nationwide
surveillance, and laboratory analysis. The EERF also provides special
analytical support for Environmental Protection Agency Regional Offices and
other Federal government agencies, as requested, as well as technical
assistance to the radiological health programs of State and local health
departments.
This report presents results of the survey conducted by EERF personnel to
assess levels of environmental radioactivity resulting from maintenance and
operation of nuclear-powered warships at the Pearl Harbor Naval Shipyard and
Environs on the Hawaiian Island of Oahu, Hawaii. The purpose of the survey
was to determine if operations related to U.S. Navy nuclear warship activities
resulted in releases of radionuclides which could contribute to significant
population exposure or contamination of the environment.
Readers of our reports are encouraged to bring comments, omissi^s, or
errors to our attention.
Charles R. Porter
Director
Eastern Environmental Radiation Facility
IX
-------
INTRODUCTION
Since 1963, the Eastern Environmental Radiation Facility (EERF),
U.S. Environmental Protection Agency (USEPA), in cooperation with the
U.S. Naval Sea Systems Command (NAVSEA), has surveyed facilities serving
nuclear powered warships on the Atlantic, Gulf of Mexico, and Pacific coasts.
These surveys assess whether nuclear powered warship operations, during
construction, maintenance, overhaul, or refueling, have created elevated
levels of radioactivity in the harbor environment. The surveys emphasize
sampling those areas and pathways that could expose the public.
In 1984, NAVSEA requested that the USEPA resurvey all active facilities
servicing nuclear powered warships over the succeeding three years. Pearl
Harbor Naval Shipyard, Oahu, Hawaii, which was surveyed by EERF personnel in
February 1985, is the first to be completed under this agreement. The Harbor
was last surveyed by the EERF (then part of the U.S. Public Health Service) in
1968 (reference 1), The 1985 survey was similar to that in 1968 except that
the more recent equipment is generally more sensitive, which results in lower
levels of detectability.
-------
Characteristics of Pearl Harbor Naval Shipyard
Pearl Harbor is located in the Hawaiian Islands on the southern shore of
Oahu, 10 miles northwest of Honolulu. As shown in Figure 1, the Harbor
consists of three major lochs, namely, West Loch, Middle Loch, and East Loch,
with a total area of approximately 2.0 x 10' meters^. The shipyard
location in the East Loch, often referred to as the Southeast Loch, contains
the submarine base, berthing areas, and repair basins.
Several major streams feed fresh water into the lochs. This feature
combined with winds, ship movement, and tidal action results -in considerable
mixing actions. In addition, sedimentation is affected by dredging in the
harbor area.
Major population areas adjacent to the harbor are Pearl City and
Waipahu. There is no commercial fishing in the harbor area; however,
recreational fishing was observed during the survey.
-------
-------
Fig. 2. Sampling Sites (Q indicates core sampling location)
-------
Fig. 3. Sampling Sites.
-------
Survey and Analytical Methods
A pre-survey meeting was held with Navy personnel to obtain information
that is useful in determining sampling sites. Specific areas of discussion
were as follows:
1. past and present radiological activities in the shipyard
2. navy's current shipyard environmental program
3. old and new (if any) discharge points
4. accidental releases
5. exclusion boundaries
Also during this meeting, sample splitting, quality assurance, and report
preparation and review were explained to the Navy personnel.
At the conclusion of the briefing, sampling sites were selected where
radioactivity most likely would be detected and in areas accessible to the
public. The density of sampling sites was based on past surveys and
professional judgment after discussions with Navy personnel. Extensive
sampling was performed at all drydocks, berthing areas, and repair facility
locations where nuclear warships are or have been serviced. Sampling sites
are shown in Figures 2 and 3. Environmental media sampled were harbor bottom
sediment, water, aquatic life, and vegetation.
Since cobalt-60 is the predominant radioisotope associated with Naval
nuclear propulsion plants, environmental sampling focused on detecting this
radioisotope. The water samples were also analyzed for tritium, since this
nuclide is produced in the coolant of light-water nuclear reactors.
An underwater gamma scintillation probe with a 10 centimeter by 10
centimeter sodium iodide detector was used with a portable multichannel pulse
height analyzer to help locate any possible areas of radioactivity. A
background reading of the bottom sediments was taken at Site 1 and was stored
in the memory of the equipment for subtraction from each subsequent
measurement to yield a net activity. A 10-minute collection period was used
for all probe measurements. In addition, harbor bottom sediment samples were
collected at all underwater probe measurement locations. Probe measurements
and sediment sampling were each repeated at approximately five percent of the
sites for quality assurance purposes. A standard Peterson dredge was used to
sample approximately the top 10 centimeters of sediment. A total of 94
sediment samples and 5 quality assurance samples were collected. At the
laboratory these samples were dried, ground to a fine powder, placed in a 400
crn3 sample counting container, and counted on a Ge(Li) or intrinsic
germanium detector for 1000 minutes.
Core samples help determine the vertical distribution of radioactivity in
harbor bottom sediment, and any radioactive materials from past operations
that have been covered with sediment can be observed in core samples. Core
-------
samples were taken using a 3.8 centimeter diameter by 61 centimeter long
plastic tube. The tube was pushed into the sediment as far as possible, the
top end capped, and carefully removed. Locations of the core samples are
shown in Figures 2 and 3. At the laboratory, the cores were frozen and cut
into 2.5 centimeter sections. The sections were individually counted without
drying on a Ge(Li) or intrinsic germanium detector for 1,000 minutes to
determine gamma emitting radioisotopes. The sections were weighed wet, dried,
and re-weighed, and the activity was reported per gram dry weight.
Water samples were collected at 11 locations in the harbor and from four
public drinking water supplies. These samples were analyzed for gamma
emitters, especially cobalt-60, and for tritium.
Aquatic life samples, consisting primarily of small fish, were collected
in the harbor and analyzed for gamma-emitting radioisotopes. These samples
were collected by divers where available. These samples were prepared by
cutting, draining, and packing them in 400 cm3 containers and counting them
on a Ge(Li) or intrinsic germanium detector for 1000 minutes.
Aquatic vegetation samples from pier pilings were collected by divers.
The samples were placed in 400 cm3 containers and counted wet on a Ge(Li) or
intrinsic germanium detector for 1000 minutes.
Direct gamma radiation exposure was monitored and recorded continuously
by a pressurized ionization chamber (PIC) mounted on the survey boat. The
average surface exposure rate at each harbor bottom sediment sampling location
was identified on a continuous recording chart.
Gamma radiation surveys were also performed on the land adjacent to the
shipyard/submarine base, focusing on areas accessible to the general public.
These measurements were made with a scintillation type survey meter that was
periodically calibrated by comparison to a PIC.
-------
Results and Discussion
The results for the water samples collected in the harbor are shown in
Table 1. No tritium was detected above the minimum detectable level of 200
pCi/1. No cobalt-60 was detected in any of the water samples. Potassium-40,
a naturally occurring radionuclide, was the only gamma emitting nuclide
detected.
There was no radioactivity detected in the four public drinking water
samples that were collected from the water supplies in the harbor area
(Table 2).
The analytical results of the aquatic life samples collected in the
harbor are shown in Table 3. Only naturally occurring potassium-40 was
detected in these samples.
The gamma exposure data collected over the land areas are summarized in
Table 4. No levels above normal background were observed in areas accessible
to the general public.
Direct gamma exposure rate measurements made from the survey boat
(Table 5) show that two locations, sites 64 and 81, were above natural
background levels. The measurement at site 64 was made immediately adjacent
to a barge where radiological work is performed and was influenced by
radioactive materials aboard the barge. The level at site 81 is elevated
because this site is near the radioactive material storage building. Both
sites are within the controlled area of the shipyard/submarine base and are
not accessible to the general public. Even if a member of the general public
were permitted to stand near these locations 24 hours a day, 365 days a year,
the radiation dose received would be much less than the annual radiation
exposure guide of 500 millirem established by current Federal regulations.
The results of the aquatic vegetation sample analyses (Table 6) indicate
small, but detectable cobalt-60 concentrations in samples from sites 6 and
20. The sample at site 6 was algae or algae-like growth taken from pilings
near the end of dry dock number 3. The concentration is small and it is
worthy of note that the concentration of cobalt-60 in the sediment sample from
this site is quite low.
-------
Extensive sampling was conducted along pier 10-10 in the general location
of a 1983 inadvertent release of low level radioactive liquid waste from a
temporary piping system used to collect radioactive water from a
nuclear-powered submarine. The presence of small quantities of cobalt-60
detected in the aquatic vegetation sample collected at site 20 could be due to
that event.
The underwater probe could not identify any specific areas of bottom
radioactivity since the levels were below the detection limit of the
instrument. This was verified when the sediment samples were analyzed by
laboratory instrumentation.
The cobalt-60 concentrations determined in the laboratory for the
sediment samples collected with the Peterson dredge are listed in Table 7.
Twenty-five of the locations sampled were chosen to duplicate those of either
the 1966 or 1968 surveys. The results from these earlier surveys are also
indicated in Table 7 where appropriate. The average radioactivity levels of
the 1985 samples are about a factor of 50 less than the average levels of the
1966-68 surveys. Decay would have accounted for about a factor of 15
reduction in radioactivity. Redistribution of the harbor sediment could
account for the remaining difference. Quarry Loch, which contained the
highest average concentration of radioactivity found in the 1966 survey
(54.7 pCi/gm), has decreased by a factor of 156 (.35 pCi/gm) in the 1985
survey. It appears that the cobalt-60 activity in the sediment is primarily
that detected in previous surveys (reference 1).
In general, the cobalt-60 concentrations in the shipyard area range from
below detectable to 0.66 pCi per gram dry weight of sediment. The highest
concentrations were found along pier 10-10 (sites 12-26) and averaged
approximately 0.3 pCi/g. However, pier 10-10 was not extensively sampled in
previous surveys, thus it is not possible to determine if sites 12 - 26 are
higher due to the inadvertent release referred to earlier or if this was the
case at the time of the earlier surveys.
The cobalt-60 concentrations of the upper sediments in the submarine base
range from about 0.1 to 2.3 pCi/g of dry sediment and are about 15 times lower
than the concentrations found in the 1968 survey (3.8 to 30.7 pCi/g).
Radioactive decay alone during this time period would have reduced the
cobalt-60 concentrations to about one tenth of their 1968 values. The added
reduction may be due to redistribution of bottom sediment over the years. As
in the previous surveys, the highest concentrations were in Quarry Loch
(sites 48 - 57).
Cobalt-60 concentrations in sediment samples from the harbor in locations
outside the immediate shipyard/submarine base area ranged from nondetectable
to 0.14 pCi/g. The highest value was at site 80; all other values were either
nondetectable or in the hundredths of a picocurie per gram, which is
consistent with decay of the low level activity found in the 1966 and 1968
surveys (reference 1).
-------
The results of cobalt-60 analyses of the core samples taken at selected
locations are shown in Table 8. The core samples in the 1968 survey show a
general increase in cobalt-60 concentration with depth. However, the data for
1985 show that this trend is no longer as apparent. The 8.8 pCi/g (20.0 to
22.5 cm) value from location 72 could be attributed to the collection of a
particle of radioactivity, since the values above and below this level are
tenfold less. At location 20, which was sampled to a depth of only about
one-half of the other core samples, cobalt-60 was detected in the upper
portion of the sample, and the lower portion had no detectable activity.
10
-------
Observations and Conclusions
1. Neither harbor water nor drinking water from surrounding areas contain
detectable cobalt-60 or tritium radioactivity.
2. Very small quantities of cobalt-60 were found in sediment and in two
aquatic vegetation samples from the harbor. No cobalt-60 was found in any of
the aquatic life samples.
3. The levels of cobalt-60 in the harbor sediment have decreased
significantly since the surveys of 1966 and 1968 and are consistent with those
expected from the radioactive decay of the amounts found in the 1966 and 1968
surveys.
4. The current practice of restricting the release of radioactive material
into the harbor to the minimum practical has been effective and should allow
the cobalt-60 radioactivity remaining in harbor sediment to continue to
decrease.
5. The levels and locations of radioactivity identified and the limited
media in which it was found show that operations related to nuclear powered
warship activities resulted in no release of radionulides having adverse
effects on public health or the environment.
11
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Table 1
Results of Harbor Water Analysis
Location
1
4
5
14
20 A
20 B
40 A
40 B
52
71
86
Radionuclide
K-40
H-3
K-40
H-3
K-40
H-3
K-40
H-3
K-40
H-3
K-40
H-3
K-40
H-3
K-40
H-3
K-40
H-3
K-40
H-3
K-40
H-3
Activity (pCi/1)
+_ 2 sigma error
0.34 + 15%
< 200
0.28 + 54%
< 200
0.32 + 19%
< 200
0.24 + 20%
< 200
0.29 + 53%
< 200
0.34 + 16%
< 200
0.35 + 15%
< 200
0.25 + 62%
< 200
0.36 + 17%
< 200
0.30 + 52%
< 200
0.35 + 15%
< 200
12
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Table 2
Drinking Water Samples
Location
Shipyard
Aiea
Waipahu
Pearl City
Radionuclide
Gamma
H-3
Gamma
H-3
Gamma
H-3
Gamma
H-3
Activity (pCi/1)
+ 2 sigma error
ND*
200
ND
200
ND
200
ND
200
*ND = No detectable radioactivity.
13
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Table 3
Results of Aquatic Life Sample Gamma Analysis
Sample Type
Fish
Fish
Fish
Fish
Fish
Clams
Fish
Composite
Location*
6
14
23
49
52
64
72
(oysters, 82
Radionuclide
K-40
K-40
K-40
K-40
K-40
K-40
K-40
K-40
Specific Gamrna
Activity (pCi/gm
wet + 2 sigma
error)
3.80 + 15%
4.50 + 23%
4.10 + 25%
4.20 + 14%
2.20 + 131%
3.00 + 101%
3.80 + 13%
3.40 + 36%
crab, fish)
* Samples were collected in the general area of the indicated location.
14
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*
**
Table 4
.*
Overland Exposure Measurements
Location Exposure
1. Hospital Point shoreline 2-5
2. Ford Island 7-8
Shoreline by USS Arizona Memorial 4-8
Pier on north end 7-8
Shoreline behind Pier 5 4-8
Dock area - water transport 4
Edge of dock area 4
Midway along boat storage 4
South of Ferry Landing 4
North edge Landing A 4
Middle edge Landing A 4
South edge Landing A 4
North edge Work Pier 4
Mid Pier " " 4
South " " 4
Midway to seaplane ramp from pier 4
Shoreline around ramp area 6-13
South East Point
3. Bridge at Canal to Ferry Landing 6-10
4. Public Park (East Loch) 10 - 12**
Survey was made while walking, so the range values represent the least
and greatest values encountered. All readings include background.
These readings were taken in the vicinity of concrete that contains
higher amounts of naturally occurring radioactivity than soil.
15
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Table 5
Exposure Measurements Observed at Sampling Sites
Site
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
Exposure
3.8
4.0
3.9
3.9
5.8
3.9
4.0
4.0
3.8
3.9
3.7
3.7
4.2
3.8
3.8
3.8
3.8
3.8
3.8
3.8
3.8
3.8
4.1
3.8
3.8
3.8
4.5
3.8
3.8
4.0
4.0
3.9
3.8
3.8
3.8
3.8
3.4
3.6
4.1
4.0
3.8
3.6
3.6
3.8
4.0
3.7
3.4
(yR/h)
- 4.2
- 4.2
- 4.2
- 4.2
- 4.2
- 4.2
- 4.2
- 4.2
- 4.2
- 4.2
- 4.2
- 4.2
- 4.2
- 4.2
Site
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
Exposure
3.7
3.8
3.8
5.3
4.3
4.5
3.5
4.5
4.0
4.1
3.8
3.7
4.0
3.5
3.6
4.1
16.1
3.7
4.2
3.8
4.0
3.9
3.7
4.3
4.9
3.7
3.6
3.6
3.8
3.8
3.8
3.8
3.8
14.7
3.7
3.8
4.3
4.0
4.1
3.7
3.8
(yR/h)
- 4.2
- 4.2
- 4.2
16
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Table 6
Results of Aquatic Vegetation Analysis
Activity
(pCi/gm
Location Radionuclide +_ 2 sigma error)
Site 6 K-40 0.49 + 25%
Co-60 0.03 + 84%
Site 14 K-40 0.80 + 58%
Site 20 K-40 0.68 + 53%
Co-60 0.02 + 75%
Site 49 K-40 0.96 + 39%
Site 52 K-40 1.40 + 37%
17
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Table 7
Cobalt-60 Concentrations in Pearl Harbor Sediments
Collected during 1985, 1968, and 1966 Surveys
Sample Location
1985 1966-1968
1
2
3
4 87
5 81
6
7
8
9
10
11 77
12 76
13
14
15
16
17
18
19
20**
-
21
22
23
24
25
26
27
28
29
30
31
32
1985*
ND***
ND
ND
0.03 + 96%
0.14 + 91%
0.04 + 55%
Nil
0.06 + 21%
0.03 + 65%
0.07 + 39%
ND
0.09 + 20%
0.05 + 70%
0.18 + 20%
0.09 + 23%
0.32 + 9%
0.66 + 22%
0.13 + 20%
0.43 + 13%
0.39 + 6%
0.34 + 17%
0.42 + 13%
0.36 + 8%
0.46 + 10%
0.56 + 15%
0.24 + 17%
0.17 + 11%
0.08 + 22%
ND
0.02 + 50%
0.05 + 35%
0.01 + 93%
0.03 + 53%
0.05 + 33%
Cobalt-60 Concentration
(pCi/g Dry Weight)
1966 1968
_ _
-
-
0.1 0.1
1.0
-
~
-
-
-
24.6 2.6
0.8
-
-
-
-
-
-
_
_ _
_ _
_ _
_
_ _
_ _
_ _
_ _
_ _
_ _
-
_ mm
_ _
-
*
Error terms are relative 2 sigma counting error.
Duplicate samples taken for quality assurance purposes.
ND = .No detectable radioactivity.
18
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Table 7 (Continued)
Sample
1985
33
34
35
36
37
38
39
40**
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60**
61
62
63
64
65
66
67**
68
69
70
71
Cobalt-60 Concentration
(pCi/g Dry Weight)
Location
1966-1968
71
-
-
62
-
53
51
-
_
50
-
-
-
38
-
-
-
32
31
-
-
29
40
27
25
-
23
-
-
-
-
12
-
-
_
-
10
-
1985*
0.10 + 39%
0.20 + 15%
0.27 + 25%
0.09 + 23%
0.06 + 25%
0.07 + 31%
0.10 + 32%
0.12 + 25%
0.14 + 21%
0.11 + 15%
0.18 + 15%
0.15 + 27%
0.09 + 31%
0.11 + 17%
0.19 + 14%
0.09 + 24%
0.16 + 24%
0.30 + 16%
0.16 + 13%
0.41 + 16%
0.54 + 12%
0.22 + 16%
0.51 + 13%
0.50 + 9%
0.24 T 9%
0.28 + 8%
0.14 + 24%
0.30 + 9%
0.12 + 14%
0.13 T 18%
0.19 T 22%
0.18 + 20%
0.42 + 7%
0.30 + 9%
0.37 + 8%
0.21 + 17%
0.32 + 9%
0.22 + 9%
0.17 + 18%
0.25 T 12%
0.22 + 11%
0.26 + 9%
1966
__
-
-
-
-
-
-
-
-
-
-
21.8
-
-
-
5.2
-
-
50.8
104.7
105.1
-
-
78.6
62.3
14.2
-
-
-
-
-
-
-
-
1.5
-
-
-
-
-
4.4
-
1968
3.8
_
-
-
3.6
-
4.0
6.2
-
-
-
-
-
-
7.9
-
-
17.5
13.9
14.1
-
-
30.7
19.5
-
4.9
-
-
5.8
-
-
-
-
8.3
-
-
-
-
-
-
-
19
-------
Table 7 (Continued)
Sample
1985
72
73
74
75
76
77
78
79
80
81
84*
85
87
88
89
Location
1966-1968
_
-
-
-
7
-
6
5
-
-
67
70
-
-
1985*
0.22 + 10%
0.24 + 18%
0.22 + 10%
0.17 + 10%
0.10 + 26%
0.22 + 12%
0.05 T 24%
0.03 + 32%
0.14 + 18%
0.04 + 36%
0.09 + 14%
0.07 + 17%
0.15 + 13%
0.13 + 12%
0.02 + 43%
Cobalt-60 Concentration
(pCi/g Dry Weight)
1966 1968
_ _
-
-
-
13.2 3.8
-
1.9
2.2
-
_
12.7
11.3
-
-
No sediment samples were collected at sites 82 and 83.
20
-------
Table 8
Sediment Core Samples - Cobalt-60 as a Function of Depth Below Surface
(pCi/g Dry Weight*)
Depth Below
Surface (cm)
0 - 2.5
2.5- 5.0
5.0- 7.5
7.5-10.0
10.0-12.5
12.5-15.0
15.0-17.5
17.5-20.0
20.0-22.5
22.5-25.0
25.0-27.5
27.5-30.0
30.0-32.5
32.5-35.0
35.0-37.5
37.5-40.0
40.0-42.5
5
ND**
ND
ND
ND
ND
ND
ND
ND
ND
ND
ND
ND
ND
—
—
—
—
14
ND
ND
ND
ND
0.22+67%
ND
ND
ND
ND
ND
ND
ND
ND
ND
ND
ND
--
20
0.46+24%
ND
0.57+56%
0.50+28%
ND
ND
ND
--
_.
--
--
-—
__
--
--
— —
--
49
ND
0.35+42%
0.59+50%
ND
ND
2.00+11%
0.29+43%
0.50+69%
0.46+35%
ND
0.30+36%
0.24+86%
0.25+43%
—
--
— —
--
Samp 1 :
51
ND
0.25+32%
0.42+86%
0.34+67%
0.23+61%
ND
0.22+63%
0.28+29%
0.39+79%
0.55+64%
0.45+23%
0.90+20%
1.40+ 9%
1.10+25%
--
—
--
ing Site
52
ND
ND
0.74+27%
0.33+74%
0.73+21%
0.67+67%
0.56+75%
0.58+30%
0.36+63%
0.33+35%
0.82+58%
0.56+80%
0.86+22%
0.61+35%
0.40+25%
— —
--
55
ND
ND
1.00+18%
0.82+28%
0.86+16%
0.57+88%
0.75+24%
0.70+33%
0.54+22%
0.64+73%
0.62+67%
0.85+23%
0.66+33%
1.10+16%
0.88+48%
1.40+32%
--
72
0.88+35%
ND
0.20+41%
ND
ND
0.21+31%
ND
0.32+29%
8.80+ 6%
0.69+45%
0.84+18%
0.69+25%
„
—
--
--
--
83
ND
ND
0.29+64%
0.24+35%
0.12+88%
0.16+35%
ND
ND
0.33+52%
0.57+16%
0.10+73%
0.06+99%
ND
ND
0.12+60%
ND
0.09+61%
86
0.34+35%
ND
0.28+23%
0.28+73%
0.38+24%
0.45+16%
0.22+74%
0.36+26%
0.28+18%
0.19+22%
__
— —
„
—
--
— —
--
* Error terms are relative + 2 sigma counting error.
** No detectable radioactivity.
-------
REFERENCES
1. Radiation Data and Reports, June 1972, Radiological Surveys of Pearl
Harbor, Hawaii, and Environs, 1966 - 1968, Daniel F. Cahill,
H. D. Harvey, Jr., et al.
*U GAFS *L(88046I)500
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