The Los Alamos National Laboratory over 16 years sent almost 50 containers of incorrectly labeled radioactive waste to the Department of Energy’s Waste Isolation Pilot Plant, the site’s prime contractor recently told the Nuclear Regulatory Commission.
The lab assigned the containers codes that indicated they should have been able to generate less combustible hydrogen during trip to the Waste Isolation Pilot Plant (WIPP) near Carlsbad, N.M., than they actually could generate.
That is according to a Wednesday letter to the commission from the Bechtel National-led Salado Isolation Mining Contractors and the NRC’s applicable rules for transuranic waste shipments.
According to Salado, none of the equipment involved with the mislabeled shipments failed and the coding errors “were determined to not represent a safety violation.” An evaluation by WIPP’s own payload engineers found “that the hydrogen concentration in the innermost confinement layer did not exceed 5% during transport,” an allowable limit, per NRC’s rules for the type of waste involved in these incidents.
The decay of radioactive elements can naturally produce hydrogen gas in some waste streams. NRC regulates radioactive waste outside of DOE sites.
Salado alerted NRC to 48 mislabeled containers in total. These were delivered inside of larger TRUPACT-II outer shells across 28 truck shipments from 2006 to 2022, the contractor said. WIPP, outside of Carlsbad, N.M., in the southeastern part of the state, is a little more than 300 miles south by road from Los Alamos, which is close to the Colorado border in the north.
In its letter to NRC, Salado attributed the repeated mislabeling to “a failure in sharing waste characterization information and effectively communicating its implications to the waste container certification process.”
WIPP is DOE’s only deep-underground repository for transuranic waste: material and equipment contaminated with elements heavier than uranium, often plutonium. Only waste arising from defense-nuclear activities such as nuclear-weapon production qualifies for disposal as transuranic waste at WIPP.
Salado, which also includes New Mexico-based subcontractor Los Alamos Technical Associates, took over the Waste Isolation Pilot Plant (WIPP) near Carlsbad, N.M., in February on a roughly $3-billion contract after a transition period that started in November. The Amentum-led Nuclear Waste Partnership was the previous WIPP prime. DOE’s Office of Environmental Management owns WIPP.
