356 RADIOLOGICAL CLEANUP OF ENEWETAK ATOLL The timing of the second soil removal operation wascritical Since al} <,.: requiring containment was scheduled to be delivered to Runit by ig hol 1979 to meetthe |5 September 1979 Cactus Dome Cap deadline. The 2) volume of soil to be moved and the severe time constraints rendereg’ infeasible to movethe soil via Enjebi as in the previous Operation, A mon rapid means of soil transport was necessary. Extensive studies of t shoreline of Boken were again conducted to determine where anq how bulk-haul craft could be used. Since the channel conditions Preventeg access by LCUs and LCM.-8s, an innovative meansto use these Craft fy bulk haul was absolutely necessary. Causeway sections had been Useq successfully in removing soil from Aomon, andit appeared possible tO us them at Boken. When the lagoon area near the sandspit off Boken in the vicinity of Koa crater was investigated, it was found that LCUscould Zain access at this location under some high-tide conditions. Fromthelip of Koa crater to the sand spit was 370 to 420 feet, depending on tide conditions. This distance could be bridged by causeway sections. All that was needed wasto find a meansto get the soil to the causeway.Since the sand on thespit was too fine to support 20-ton dump trucks, the LARC. LX was employed to transport them from the beach stockpile on Boken north of Seminole Crater across the crater and the sand spit to the landward end of the 360-foot causeway. The trucks were then required to back from the LARC-LX out the 360-foot causeway to dischargetheir loads on to the LCUs,which had navigated from Koacrater tothe seawarg end of the causeway. The truck then was driven forward off the LCUs, along the causeway and aboard the LARC-LX whereit was ferried back across the sand spit and Seminole Crater to the beach stockpilesite. A photograph of this procedure in operation is shown in Figure 7-24. Even though this method was time consuming, it proved to be muchfaster than the method previously used to remove soil from Boken, and it permitted the use of bulk-haul boats. In addition to the LCU-Causeway-LARC combination, limited use was made of LCM-8s and 5-ton dump trucks. These all-wheel-drive dump trucks were able to negotiate the sand spit to the causeway. The LCM-8s could beach alongside the causeway only during high tides. Depending on the tides, they could accept two to four 5-ton dumptruck loads each. Since they werepartially loaded, the LCM-8s would then proceed to Lujortofill. the remainder of the craft with the soil excised as a result of subsurface contamination discovered there during the Fission Products Data Base Survey. With these plans fully established, Company B, USAE, began the excision on II June 1979, and all soil was transported to Runit by 7 July 1979, 9 days ahead of the deadline. Figures 7-25 and 7-26 show Boken before and after cleanup operations. ,