The radioactivity of high-level radioactive waste affords proliferation resistance to plutonium placed in the periphery of the repository or the deepest portion of a borehole.
Yet plans to turn the zone into a nature reserve are under threat from the nuclear industry, which wants to use the area to dispose of high-level radioactive waste.
Left behind were 53 million gallons of high-level radioactive waste, 25 million cubic feet of solid radioactive waste and 200 square miles of contaminated groundwater underneath the site.