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RADIOLOGICAL CLEANUP OF ENEWETAK ATOLL

c. Preserve the capability to execute the sheet pile containment Option
All sheet pile and other necessary supplies and equipment needeq to
execute that option would be obtained and shippedto the atoll on the
next barge.

d. Provide a desilting capability for removing suspendedparticles from
water.
e. Complete the project, including backfilling and backfill profile
samples, not later than 30 May 1979.
During the meeting, DOE representatives, in concert with Field

Commandrepresentatives, provided radiological guidance as follows:
a. Debris will be recovered throughout the crypt.

b. An attempt will be made to excavate transuranic concentrations

exceeding 400 pCi/g at any depth encountered. Water-saturateg

samples will be filtered and field scanned.

c. Sediments will be sampled at predesignated grid nodes and analyzeq
using field techniques to document activity at the final eXCavated
depth. Each grid will be 5 meters on a side (25 square meters).
d. After backfilling has been accomplished, profile samples will be

collected at the sampling nodesto a depth of 180 centimeters. The

core profile samples collected will be homogenized and aliquoted,
yielding one concentration value representing that grid to ensurethat
values do not exceed 400 pCi/g.

e. Recovered contaminated soil piles and debris will be samples and

monitored to obtain an estimated inventory of radioactive material
recovered.

CRYPT SURVEYS: NOVEMBER 1978
Based cn instructions from the 8 November 1978 conference,a 5-by-5-

metergrid was established by DOE-ERSP and wassurveyed and staked by

a USAEsurveyor. This grid, shown in Figure 7-28, was used for all

subsequent surveys and operations in the Aomon Crypt. The surface of

the Aomon Crypt was surveyed by DOE-ERSP using the IMP on 25metergrid. No surface readings above 40 pCi/g were found.46
A magnetic survey4? of the Aomon Crypt was carried out by U.S.

Oceanography of Honolulu, Hawaii, during the period 17-20 November

1978. A proton procession magnetometer with a dual sensing element ona

30-meter cable was used to determine the location and amountofferric
material buried in the crypt area. Positioning was accomplished using the
5-by-5-meter grid system established by the USAEsurveyor.

To obtain an average reading for the total field intensity of the area,

approximately 20 readings were made outside the grid area, in locations
ba

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