A record of decision was amended Friday as one of the regulatory steps needed for the Department of Energy to proceed with moving cesium and strontium capsules from underwater storage to dry storage at the Hanford Site in Washington state.
The amended ROD specifies that interim storage of the capsules will continue, but in dry storage rather than underwater storage. It became official with publication in the Federal Register.
There are 1,335 cesium capsules and 601 strontium capsules stored under 13 feet of water at the Waste Encapsulation and Storage Facility (WESF) adjoining the B Plant processing facility in central Hanford. The Energy Department has previously said the transfer could begin in 2022.
The storage of the capsules, which hold radioactive material removed from Hanford waste tanks from 1974 to 1985, was covered in a 2013 Record of Decision for the Final Tank Closure and Waste Management Environmental Impact Statement for the Hanford Site. At that time DOE decided not to take any action on the capsules.
The Energy Department had considered moving the capsules to dry storage for more than a decade. But it took a 2014 report by DOE’s Office of Inspector General to push the project forward. The IG said the capsules should be moved to dry storage because of the potential for damage to the storage pool in a severe earthquake. A loss of water or water cooling systems could cause the capsules to overheat and breach.
Regulatory action is expected to continue with an announcement this week of a public comment period to change milestones in the Tri-Party Agreement on Hanford cleanup to reflect the plan to move the capsules. In addition, DOE has held a public comment period on changing the Hanford Dangerous Waste Permit issued by the Washington state Department of Ecology to reflect the capsule relocation plans.