310

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RADIOLOGICAL CLEANUP OF ENEWETAK ATOLL

Ry

The13 millirad dose assumed the worst case where residence, commercia)

agriculture, and food gathering took place on islands with Soil
contaminated to 40, 80, and 160 pCi/g, respectively. If the people followeg
the EIS Case 3 habitation plan and lived only on the southern islands.
which would measure less than 2 or 3 pCi/g—the dose to bone would be

much lower. 95:96

DOE endorsed the new guidelines as fully in keeping with the

recommendations and cleanup criteria contained in the EIS. The
requirement to removeall concentrations over 400 pCi/g was unchangeq

Specific guidance was provided for concentrations in the 40 to 400 PCi/g
range which were to be decided on a case-by-case basis. The doseestimates
were done with the best models available, using the EPA criteria as a goal.

DOE hoped the cleanup would come within a factor of three or fourof the

EPA goal, in which case it could meet the spirit and intent—if not the
letter—of EPA guidance.97
SOIL CLEANUP BRIEFING

Thefinal briefing covered the estimated volumesofsoil to be removed,

the assets available to excise and transport soil to Runit, and someofthe
options for accomplishing soil cleanup. It was a revised version of the

briefing given to Director, DNA on II April 1978. Although data were
presented on all 21 northern islands, only five required soil cleanup to

satisfy the original dri-Enewetak desires for use: Runit and the islands
from which soil would have to be transported by boat, i.e., Aomon,

Boken, Enjebi, and Lujor.
The soil volume data varied somewhat from the DOE-ERSP estimates.
The most significant factor in Field Command’s estimates ofsoil to be
removedandtransported wasthe so-called ‘‘Treat Factor.’’ This wasa soil
removal ‘‘experience factor’? which COL Treat developed to adjust the
initial estimates of soil volumes. The principal aim of the “‘Treat Factor”
was to provide decision-makers with a reasonable approximation of the
amount of soil that would ultimately have to be removed from an area
with high surface contamination in order to reduce it, by means of
successive 6-inch cuts, to a designated level. It was based upon
consideration of experience from other soil cleanup operations; e.g,
Hattiesburg, Rocky Flats, etc. Application of the Treat Factor caused
estimated volumes of soil which had a surface contamination of over 400
pCi/g to be multiplied by a factor of four. (This meant that it was estimated
that soil removal teams would have to make four 6-inch cuts to bring the
surface levels down to acceptable residual levels of radiation. In essence,it

was a compensation for the fact that experience had indicated that onecut
normally was not sufficient, spillage and cross contamination could be

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