Dirt contaminated by herbicides buried three decades ago on a Hanford Nuclear Reservation wildlife refuge will be hauled away, state and federal officials say.
Cleanup agencies will dig up about five cubic yards of soil contaminated with a herbicide, as well as remove remnants of 11 large chemical storage tanks buried on the Wahluke Slope north of the Columbia River.
Less-contaminated dirt will be turned over and spread out to allow the herbicide to evaporate, the U.S. Environmental Protection Agency and the state Department of Ecology said in preliminary cleanup plans.
The cleanup is estimated to cost about $125,000.
The cleanup was complicated when “very minute” traces of dioxin and the herbicide 2,4,5-T were discovered. Dioxin is a toxic byproduct of herbicide manufacturing and 2,4,5-T was banned for use in the United States in the 1970s.
Some of the contaminated dirt may be taken to a disposal facility on the Hanford reservation, said Michael Turner of the Ecology Department’s Hanford Project. But dioxin wastes cannot be accepted there and will have to be hauled to another disposal facility, he said.
The site is where tanks and contaminated dirt were buried after a spill in Eltopia in the mid-1960s.