Feds and state regulators at the Department of Energy’s Hanford Site in Washington state have agreed on new steps to address leaking tanks of radioactive waste, including a new presumed leaker acknowledged in August.
The steps include more leak detection and reconsidering the date for emptying a leaky tank.
The deal announced this week between DOE and the Washington Department of Ecology updates an order the two sides agreed to in August 2022 for single shell tanks 241-B-109 and 241-T-111.
“Work required under Agreed Order No. 21304 is ongoing but not yet complete,” according to an addendum to the order, dated Nov. 20 and signed this week by DOE Hanford Site Manager Brian Vance and Stephanie Schleif, program manager, for Washington Ecology’s nuclear program.
The latest updated order follows DOE’s acknowledgement in August that a third tank, T-101 “is more likely than not leaking” some radioactive or chemical contamination into the soil near the Columbia River.
The updated order sets out plans for “leak detection, monitoring, and initial actions required” for the single-shell tank system until such tanks are emptied.
The order says DOE will investigate the “practicability of installing and operating an active ventilation system for tank 241-T-101,” and report back to the state by Jan. 31. Also, by Jan. 31, DOE and the state will negotiate an updated waste retrieval milestone for the tank.
T-101 is a half-million-gallon tank built in the early 1940s and received waste between 1945 and 1979, according to the latest order. In the early 1990s, DOE pumped most of the liquid out of 101 and other tanks and the tank currently has roughly 93,000 gallons of waste, mostly sludge and salt cake, according to this week’s order.
Following a public comment period, the parties expect the Leak Response Plan will become part of Revision 9 of the Hanford Site-Wide Permit, according to the revised order.
DOE and its contractors are already “designing and constructing a surface barrier over the T Farm and a nearby basin where runoff will evaporate,” according to the updated order. The barrier should block rain or snowmelt from seeping into the ground and spreading any contamination, according to the revised order.
A third party can still challenge this latest updated order to the state Pollution Control Hearings Board, according to the document.
Next year, DOE plans to start turning some of the less-radioactive waste from Hanford underground tanks into a solid glass-like form at the Direct-Feed-Low-Activity Waste Facilities at the Bechtel-built Waste Treatment and Immobilization Plant.
