Another round of looking at potentially less expensive options to treat the stew of radioactive and hazardous chemical waste stored in Hanford’s underground tanks has brought out the skeptic in some Northwest officials.
“Just once I’d like to hear ‘How can we do it better? How can we ensure protection for as long as these wastes remain hazardous?’” said Ken Niles, nuclear safety administrator for the Oregon Department of Energy.
He was among the invited speakers at a two-day meeting in Richland last week of leading national researchers assembled as a committee of the nonprofit National Academies of Sciences, Engineering and Medicine.
Legal documents, including the Tri-Party Agreement and a federal court-enforced consent decree, also require or are based on the plan to vitrify all of Hanford’s tank waste, she said. The vitrification plant would produce glass logs immobilizing the waste.
But a spring 2017 report by the Government Accountability Office said that its expert panel had determined that grouting — mixing the waste into a concrete-like substance — would be less expensive than vitrifying some of the excess low-activity radioactive waste and allow the waste to be treated sooner.
Multiple studies have shown that grout would not perform as well as glass to keep low level radioactive waste immobilized once the treated waste is buried at a Hanford landfill, local officials said. Radioactive contaminants would leach out of grout into the groundwater and then move toward the Columbia River over thousands of years.
Those studies include a comprehensive look at alternative ways to treat low activity radioactive waste from 2003 to 2006, which found that grout was “not as good as glass,” Smith said.
Groundwater would be contaminated at foujradior times the drinking water standard for radioactive technetium 99, the analysis found. The low activity waste will include both technetium 99 and radioactive iodine 192.