Surface soil samples were taken at four sites using the standard surface sampling pattern, giving a

total of eight composites. Two additional composites were taken at a fifth site at 10 em depth.
The TRU values ranged from 0.71 pCi/g to 4.32 pCi/g, showing good agreement with the 1972 results.

Leroy was also sampled for the Fission Product Data Base in support of the dose assessment.
Because no grid lanes were cut on this island, the eight sampling locations, shown in Figure 7-1, are
only approximate. The results are summarized in Tables 7-1, 7-2 and 7-3. The activity declined
with depth, as had the 1972 samples, and since the maximum TRU value was 37.3 pCi/g in a 0-5 em
sample, no further investigation was done.

The island average transuranics value reported in the Certification is 2.5 pCi/gm for surface soil,
and the transuranics classification is Residence.
7.2.0 Other Southern Islands

All of the 14 islands in the southern half of Enewetak Atoll that were not discussed in sections 7.2.1

through 7.2.4 are less than 17 hectares (ha) in area. None had any known or suspected burial areas
or ground zero sites, and there were few scientific stations and relatively little debris on these

islands. The accumulated H + | hour exposure rate was very low for all these islands.

The 14 islands listed in Table 7-4 were sampled during the 1972 survey; in most cases, the sampling
included some 0-15 em cores, a few 0-35 em profile samples, and some animal and vegetation
samples. In general, the depth distributions of 137 Og, 90s, and 239,240py followed one of two
patterns: In areas with dense vegetation, the activity decreased slowly within the top 20 em, while

in sparsely-vegetated areas, activity was homogeneous and very low.

Tables 7-1, 7-2 and 7-3

summarize the results for 0-15 em core samples from these islands for 137g, 90sP and 239,240 py,

respectively.

Surface soil samples were taken on these islands during the cleanup.

All samples had TRU activity

less than 1 pCi/g. No IMP measurements were made because the surface TRU activity was too low
to obtain meaningful data. Also because of the low activity, no Fission Product Data Base samples
were taken.

Consideration was given to sampling the reference points Mack and Oscar in the lagoon.

Oscaris

now a concrete pillar washed by waves at high tide, and it was impossible to sample the concrete
surface safely. The above-surface structure at Mack no longer exists; only a subsurface prominence
remains. Sampling of Mack was therefore considered to be neither feasible nor necessary.
Other than debris removal, no cleanup was required on any of the southern islands.

TABLE 7-4. NUMBER OF SOIL SAMPLING LOCATIONS ON SMALL SOUTHERN ISLANDS.

Boko
Munjor
Inedral
none
Jinedrol
Ananij
Jinimi
Jedrol
Bokandretok
Ikuren

Irwin
James
Keith

Boken
Ribewon
Kidrenen

Name

Henry

Name

Mut

Size (ha)
0.4
0.7
1.6
200
0.9
10.0
1.2
2.2
0.3
16.8

16.3

12.0
7.6
9.8
oQ

Sam
Tom
Uriah
Van
Alvin
Bruce
Clyde
Rex
Walt
Glenn

Island

oe

Marshallese

bo

Site

Numberof Soil
Sampling Locations

1972

1979

15

4

5
5
8
6
5
13
4
7
5
28
8
8
13

4
4
4
4
4
4
4
4
4
3
4
4
4

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