BORAX Experiments - BORAX-I Cleanup

BORAX-I Cleanup

The destruction of BORAX-I caused the "aerial distribution of contaminants resulting from the final experiment of the BORAX-I reactor" and the likely contamination of the topmost 1 foot of soil over about 2 acres in the vicinity. The site needed to be cleaned up prior to being used for subsequent experiments. The 84,000-square foot (7,800 m2) area was covered with 6 inches of gravel in 1954, but grass, sagebrush, and other plants reseeded the area since then. The BORAX-I burial ground is located about 2,730 feet (832 m) northwest of the Experimental Breeder Reactor-1, a publicly-accessible national monument. Since 1987, the United States Environmental Protection Agency has classified the burial ground as Superfund site Operable Unit 6-01, one of two such sites (along with SL-1) at the Idaho National Laboratory. In 1995, the EPA ordered the primary remedy of the burial ground should be: "Containment by capping with an engineered barrier constructed primarily of native materials." The site is expected to produce no more than a 2 in 10,000 increase in cancer risk for long term residential use after 320 years, with no significant decrease after that time. This risk calculation ignores the shielding provided by the soil cover, which at the time of the EPA decision had reduced exposure to little more than background level, and makes very pessimistic modeling assumptions that greatly increase the projected risk, to deliberately err on the high rather than low effect side.