464 Ss RADIOLOGICAL CLEANUP OF ENEWETAK ATOLL To assure that cap sections were 18 inches thick, a gauge was fabricateg It had the appearance of a huge comb with teeth 18 inches tong Projections on either end were placed atop the side formsbefore a S€Ction was poured and moved from one end of the section to the other. This moved the teeth across the surface to be capped so that any depressions o, protrusions could be detected and corrected. After several sections haq been placed, it appeared that some capsections were turning out to be over 20 inches thick, and considerably more concrete was being used than wag believed necessary. This appeared to be a result of the compaction of the disturbed soil under the tons of heavy wet concrete pouredin eachsection 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 cleanup earlier in the project began to adversely impact capping operations in August 1979. The USAEhad been conducting whatthey believed to be the final sweeps to removethelastof the debris from the ocean reef of Runit near the Lacrosse Crater. Though i this debris had been examined several months previously and foundto 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 wasto be placed and surrounded with concrete.!3° 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 surroundingsoil 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 designedto contain the material and prevent erosion rather than act as a radiation shield, completely surrounding and encapsulating the material in concrete appeared to bein conformance with the intent and integrity of the structure. These