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RADIOLOGICAL CLEANUP OF ENEWETAK ATOLL
FIGURE 8-22. TREMIE BARGE AND CRANE.
cement and one-half bag of attapulgite per cubic yard of contaminatedsoil.
The contaminated soil had been filtered through a I-1/2-inch screen at the
screen plant, with oversized material treated as debris. This step was
essential because the concrete pump could not accommodate aggregate
larger than |-1/2-inch nominal diameter. Attapulgite clay was used to
improve the workability, lubrication, and cohesivenessof the slurry in the
pumping and underwater placement operation. Water was added and the
materials were mixed in the transit-mix truck en route to the tremie pump.
There the slurry was pumped through the pipeline and deposited on the
crater floor.
OPLAN 600-77 stated that contract consultant services, if required,
would be provided during actual tremie placement operations.®! In
response to an inquiry from Field Command, U.S. Army Support
Command, Hawaii (USASCH) advised that such services were desirable,
not only for tremie mix and placement but for quarry and batch plant
operation.62 As a result, Field Command arranged for POD to provide
necessary technical assistance.63.64 On 13 June 1978, four technical
representatives arrived at Enewetak to assist in the final calibration and
startup of tremie operations. On {5 June 1978, the first 40 cubic yards of
contaminated slurry were batched and tremied onto the floor of Cactus
Crater. Based on the advice and assistance of the technical representatives, |
adjustments were made to the plant operation to improve output. By the
end of June, 1,223 cubic yards of slurry had been tremied.