302
RADIOLOGICAL CLEANUP OF ENEWETAK ATOLL
b. Considering the physical and ecological limitations to remova| of
transuranics from the Enewetak Atoll, the Bair Committee
recommendedthe following cleanup criteria:
(1) All one-quarter or one-half hectare areas on residentialislangs
should be cleaned unless the average concentration in surface
(0-3 cm) soil does not exceed 40 pCi/g (with 70 percen,
confidence). That is, each one-quarter or one-half hectare area
should be cleaned if the average concentration plus one-haj
standard deviation (for the unit area) exceeds 40 pCi/g. From
the
information
then available and
being used for dose
assessment, the Committee believed this procedure woulg
provide a reasonable expectation that dose in the bone and lung
would be commensurate with the EPA guidance. [n terms of
radiation dose-sparing benefit to future inhabitants, the
Committee pointed out that cleanup of a standard area on q
residential island was worth about four times as much as Cleanup
to a given level on an agricultural island and 12 times as much as
cleanup of the same area to the same level on an islang
designated for food gathering. In the light of existing
contamination levels and available cleanup resources, it would
appear that cleanup of all one-quarter or one-half hectare areas
on residential islands according to the above criteria should
receive first priority.
(2) Because the other islands may have increased use over that
currently assumed, a secondpriority should be the cleanup of
agricultural island half-hectare areas unless the average
concentration for the unit does not exceed 80 pCi/g (with 70
percent confidence).
A third priority should be the cleanup of food-gathering island
half-hectare areas unless the average concentration for the unit
does not exceed 160 pCi/g (with 70 percent confidence). If
resources were exhausted, some islands might not be cleaned
up, and final dose assessment might indicate that these islands
would have to be quarantined.
The Committee noted that the soil profile on Lujor was anomalous,
since the concentration of transuranics appeared to be uniform with depth.
They. believed that the possibility of effective cleanup for use as a
residential or agriculture island was remote. However, the possibility of
covering Lujor with the less contaminated soil from the residential islands,
and perhaps from the agricultural islands, should be considered for
lowering the average surface contamination levels and reducing the
logistics problems of transporting the soil from the other islands to Runit.
(3)