EPA approves expanded waste storage at WIPP

The justification: The EPA said its decision to approve the DOE’s request for the replacement panels was “based on a thorough review of information submitted by DOE, independent technical analyses, and public comments.” Notice of the approval was published in the August 19 Federal Register.

The DOE is required by federal regulations to report any planned changes in activities or conditions at WIPP to the EPA, which has authority to oversee and certify the long-term performance of the repository.

In approving Panels 11 and 12, the EPA said it found that there is “reasonable expectation” that the additional panels will comply with the requirements of 40 CFR Part 194 and the release limits of 40 CFR Part 191.

The panels: Mined from WIPP’s salt formation more than 2,100 feet underground, each panel consists of seven rooms as long as a football field—33 feet wide, 300 feet long, and 16 feet high—where waste is emplaced.

After being filled with waste packages, the panels will be sealed and the salt, which moves, or “creeps,” at about 2 to 4 inches per year, will eventually encapsulate the packages, isolating the waste from the surrounding environment.

Because of salt creep, mining at WIPP is timed so that a panel is only ready when it is needed for waste emplacement. Mining on Panel 11 began in January 2024.

Other WIPP news: Also on August 19, the Los Alamos Field Office of the DOE’s Office of Environmental Management announced that its Los Alamos National Laboratory cleanup contractor completed its 200th shipment of transuranic waste to WIPP for safe disposal earlier this month.

The shipment consisted of three standard waste boxes containing segments of corrugated metal pipes (CMPs) formerly buried at Area G in LANL’s Technical Area 54. The CMPs contained cemented radioactive liquid waste from a former LANL radioactive liquid waste treatment facility that operated during the Cold War era. In 2024, Newport News Nuclear BWXT (N3B)–Los Alamos completed work to retrieve and size-reduce the set of 158 CMPs and began shipping them to WIPP earlier this summer.

Since beginning shipments in October 2018, N3B Los Alamos has sent more than 665 cubic meters of transuranic waste—or about 3,194 55-gallon drums—from Technical Area 54 to WIPP.

“Our 200th transuranic waste shipment represents tangible progress in one of the core areas of our work at LANL,” N3B Los Alamos president and general manager Brad Smith said. “There’s more to be done, and the N3B workforce’s ongoing emphasis on safety and operational excellence will continue to be critical as we work to address the remaining legacy waste at LANL.”