464 RADIOLOGICAL CLEANUP OF ENEWETAK ATOLL Runit To assure that cap sections were 18 inches thick, a gauge wasfabricated. It had the appearance of a huge comb with teeth 18 inches long. Projections on either end were placed atop the side forms before a section was poured and moved from one end of the section to the other. This movedthe teeth across the surface to be capped so that any depressions or protrusions could be detected and corrected. After several sections had been placed, it appeared that somecapsections were turning out to be over 20 inches thick, and considerably more concrete was being used than was believed necessary. This appeared to be a result of the compaction of the conclusic represent placemen the adequ intended. in this m: disturbed soil under the tons of heavy wet concrete pouredin each section the FRST which, in turn, would require more concrete to fill the form. To compensate for this effect, the teeth on the gauge were cut to 16-1/2 inches.!28 However, despite these procedures and findings, subsequent core sampling found that somesections varied, both thicker and thinner, from the specified thickness. !29 ADDITIONAL DEBRIS CONTAINMENT Failure to accomplish Runit debris cleanupearlier in the project began to adversely impact capping operations in August 1979. The USAEhad been conducting what they believed to be the final sweeps to removethelast of the debris from the ocean reef of Runit near the Lacrosse Crater. Though this debris had been examined several months previously and found to be ‘“‘vellow’’ (disposable by lagoon dumping), after it was removed from the water and allowed to dry, FRST screening disclosed that some of the debris was actually ‘‘red’’ (contaminated, requiring crater containment). It was the consensus of the USAE and the JTG that this small quantity of debris could be accommodated in the dome, despite the fact that capping operations were proceeding rapidly. Depressions were to be made in the surface of the moundto serve as dikes in which debris was to be placed and surrounded with concrete.!30 Properly executed, this would comply with the POD design. In some cases, however, debris was placed inside the cap section forms in such a manneras to extend above the surrounding soil level. Then, the concrete was placed in the cap section. Consequently, several cap sections contain pieces of contaminated metallic debris embedded in the concrete, with the result that less than 18 inches of concrete cover the debris. Inasmuchas the debris was placed in the bottom of the cap sections, it was concluded that spalling would be highly improbable. Also, since the dome was designed to contain the material and prevent erosion rather than act as a radiation shield, completely surrounding and encapsulating the material in concrete appeared to be in conformance with the intent and integrity of the structure. These As the debris on more anc more red dome. 132 heard the was direc was advis used for POD w problem. was made side (Fig: the keyw contamin clean con the dome The 7: for exect construct foot addi the wate sweeps C contamir sealed an As the Two mo! exposed could be material. on 17 N CJTG r requeste: the stocl cubic yar in drums