Alissa Tabirian
NS&D Monitor
7/31/2015
Los Alamos National Laboratory’s (LANL) proposition to credit pipe overpack containers (POC) with a damage ratio of zero at the Area G nuclear waste disposal site was found “inappropriate” and “not technically defensible” by personnel from the National Nuclear Security Administration (NNSA), the Department of Energy’s (DOE) Office of Environmental Management, and LANL itself, according to a Defense Nuclear Facilities Safety Board (DNFSB) site representative report released this week for the week ending July 3.
DOE defines damage ratio as the “fraction of material actually impacted by the accident-generated conditions,” indicating the amount of radiation that might be released from an accident. The issue regarding use of the POCs that contain radioactive wastes was raised by the NNSA following LANL’s submission of an “Evaluation of the Safety of the Situation/Justification for Continued Operations (ESS/JCO) that proposed crediting POCs with a damage ratio of zero,” the report says. The May ESS/JCO concerning safety basis limits has not yet been approved, during which time LANL has restricted its receipt of transuranic waste at Area G, according to a site rep report from the time of the submission. The latest report notes that LANL “is expected to withdraw and resubmit a revised ESS/JCO in mid-July,” which is “largely due to the conclusion that applying a damage ratio of zero to the POCs is inappropriate.” The report also says that none of the five facilities at LANL that host POCs “currently credit the POC with a [damage ratio] of zero; however, the Plutonium Facility is currently using a DR of 0.1 and . . . the Transuranic Waste Storage Facility, currently under construction, had planned to use a [damage ratio] of zero.”
