Runit (Yvonne) Cleanup and Crater Containment Another large volume of soil was bulldozed onto the reef in 1958 to provide a site for the Cactus event of Operation Hardtack I. The Cactus shot left a crater approximately 37 feet deep and 346 feet in diameter (Figure 8-2). The northern half of Runit was significantly contaminated; however, only one shot, Erie, was detonated on the southern part of the island. South Runit—the area south of Station 1310, a large bunker in the center of the island (Figure 8-3)}—was used primarily as a base camp, with an airstrip, boat landings, and other support facilities. By the time cleanup began, vines and grass covered most of the island, bordered by heavy brush (See Figure 8-4).3 In the absence of human activity, Runit had — ee oe become the roosting and nesting ground for one of the largest tern colonies on the atoll, numbering thousands ofbirds. There were two reported burial sites on Runit: one near Station [310 where a jar of plutonium-contaminated sand was buried, and the other a small, fenced area where another jar of contaminated sand, a box of contaminated material, and two small discs were believed to be buried. Other hazardous items on Runit included several bunkers, nine derelict landing craft which had been beached for shore protection (Figure 8-5), contaminated concrete blocks and slabs, wooden towers, and large quantities of contaminated metal scrap. An estimated 4,064 cubic yards of contaminated debris were to be removed from Runit, 56 percentofall the contaminated debris identified in the Environmental Impact Statement (EIS). An additional 6,155 cubic yards of noncontaminated debris were identified for removalin the EIS.4 Runit was one offour islands identified in the EIS (Vol. I, Table 5-4) for cleanup of plutonium concentrations over 400 pico curies per gram (pCi/g). It was estimated that there were less than 1,500 cubic vardsof soil on the surface with such concentrations.* The EIS estimate of soil volumes to be removed to reduce the concentrations on Runit to less than 40 pCi/g was 63,725 cubic yards. This was in general agreement with the Department of Energy-Enewetak Radiological Support Project (DOEERSP) estimates in April 1978.6 The desired use of Runit by the driEnewetak, in the first edition of the Master Plan, was for agriculture, to restore the large groves of coconuts it had once borne. Levels of strontium and cesium, the principal radiological constraints on agriculture throughout the atoll, were considerably lower on Runit than on Enjebi or other northern islands proposed for agriculture. It was estimated that 20,000 cubic vards of soil would have to be removed to bring Runit to below 80 pCi/g, the Bair Committee guideline for agriculture, or 14,500 cubic yards to reduce concentrations below 160 pCi/g and qualify Runit for visitation and food-gathering use.’ The material was to be placed in the craters where tt would not be readily available to man and where it could