v R unit (Yvonne) Cleanup and Crater Containment Another large volume of soil was bulldozed onto the reef in 1: provide a site for the Cactus event of Operation Hardtack I. The| shot left a crater approximately 37 feet deep and 346 feet in dic (Figure 8-2). _ The northern half of Runit was significantly contaminated; ho’ only one shot, Erie, was detonated on the southern part of the South Runit—the area south of Station 1310, a large bunkerin the of the island (Figure 8-3) —was used primarily as a base camp, w airstrip, boat landings, and other supportfacilities. By the time cl began, vines and grass covered most of the island, bordered by brush (See Figure 8-4).3 In the absence of humanactivity, Run become the roosting and nesting ground for one of the larges colonies on the atoll, numbering thousands ofbirds. There were two reported burial sites on Runit: one near Static where'a jar of plutonium-contaminated sand was buried, and the c ~ small, fenced area where another jar of contaminated sand,a | contaminated material, and two small discs were believed to be t Other hazardous items on Runit included several bunkers, nine ¢ landing craft which had been beached for shore protection (Figur: contaminated concrete blocks and slabs, wooden towers, and quantities of contaminated metal scrap. An estimated 4,064 cubic y. ~- contaminated debris were to be removed from Runit, 56 percentof contaminated debris identified in the Environmental Impact Stat (EIS). An additional 6,155 cubic yards of noncontaminated debri identified for removalin the EIS.4 Runit was oneoffour islands identified in the EIS (Vol. 1, Table 5 cleanup of plutonium concentrations over 400 pico curies per (pCi/g). It was estimated that there were less than 1,500 cubic yards on the surface with such concentrations.> The EIS estimate of soil vc to be removedto reduce the concentrations on Runitto less than 4C was 63,725 cubic yards. This was in general agreement wit ~ Department of Energy-Enewetak Radiological Support Project | ERSP) estimates in April 1978.6 The desired use of Runit by tt Enewetak, in the first edition of the Master Plan, was for agriculti restore the large groves of coconuts it had once borne. Levels ofstrc | S and cesium, the principal radiological constraints on agric throughout the atoll, were considerably lower on Runit than on En other northern islands proposed for agriculture. It was estimate 20,000 cubic yards of soil would have to be removed to bring R' below 80 pCi/g, the Bair Committee guideline for agriculture, or cubic yards to reduce concentrations below 160 pCi/g and qualify Ru visitation and food-gathering use.’ The material was to be placed craters where it would not be readily available to man and where i