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RADIOLOGICAL CLEANUP OF ENEWETAK ATOLL
ACCOUNTING FOR CURIES

One additional goal of the pilot project was to develop methods fo

measuring the amount of radioactivity in the excised soil and for Orting

the soil into two stockpiles on Runit. One stockpile would consist of soi

with contamination levels greater than that to which Runit would be
cleaned (assumed to be 400 pCi/g), and the otherofsoil with lowerlevels
Thefirst stockpile would have to be placed in the crater, while the secong

could be left on Runit if resources were not sufficient to encapsulate it

The procedure also would provide an accounting for the total curies of

radioactive material removed. Two methods of measurement weretesteg

A dirt ramp was prepared to the top of an old Japanese bunker on
Aomon. The in situ van was driven to the top of the bunker where its
detector could be placed over the loaded dump truck beds to measure
radiation intensity. Results varied with the configuration of the load anq
the positioning of the truck. As an alternative, one scoop of soil was

removed from each front loader bucket before the soil was dumpedinto

the truck. Individual scoop samples were composited to produce one
sample per truck. The bucket loader sample and the truck top sample were
each shaken vigorously, then one petri dish of soil was removed for
scanning. On-site scanning of the first 18 truckloads indicated that both of
these sampling methods tended to give much higher readings thanin sity
surveys of the area before, during, and after soil removal operations. The
truck sampling techniques were not pursuedfurther.
The methodfinally adopted for calculating radioactivity removed from
an area and taken to Runit was to employ the in situ data from before.
during, and after soil excision, plus the subsurface profiling data.68.69
Results were sufficiently accurate to account for total curies andto sort the
highly active (hot spot) soil from the low-level soil.

TRANSPORT TO RUNIT
Several methods of transporting contaminated soil from beach

stockpiles to stockpiles on Runit were tested during the pilot soil removal
project. The U.S. Navy Element (USNE)was tasked to support the project
with one LCU, two LCM.-8s, and a warping tug with two causewaysections
assembled asa ferry or floating platform. The USAE wastaskedtotest the
LARC-LX for soil transport. Intensive reconnaissance efforts were
conducted to identify alternative channel approaches and to quantify tidal
restrictions to all approaches. Channel improvement techniques were
included in the overall plan. Variations and modifications were authorized
with HQ JTG approval.

Select target paragraph3