Chris Schneidmiller
WCM Monitor
9/4/2015
The Idaho National Laboratory needs a more stringent approach to determine whether it must update its assessment of the potential threat posed by earthquakes to the facility, the head of the Defense Nuclear Facilities Safety Board said in a letter this week to the Department of Energy.
Department rules mandate that each DOE facility review its probabilistic seismic hazard analysis (PHSA) once per decade for “significant changes in data, criteria, and assessment methods that would warrant updating the PHSA,” according to DNFSB Chair Joyce Connery. She said, though, that the laboratory’s approach in assessing the need for a PHSA revision “is not well-defined and may not be technically defensible.”
“INL is planning to perform this evaluation with a ‘risk-informed’ approach that relies on a preliminary seismic hazard analysis not rigorous enough to be used in the evaluation or design of certain high-hazard nuclear facilities at INL,” Connery stated in the Aug. 31 letter to Matthew Moury, associate DOE undersecretary for environment, health, safety and security. “This ‘risk-informed’ approach is not defined in DOE directives, and we are concerned that INL is completing work without first defining how the results will be objectively evaluated.”
Connery’s letter specifically cites the lab’s Fuel Manufacturing Facility, which is part of a larger complex that researches and develops nuclear fuels, and the Integrated Waste Treatment Unit, a not-yet operational system intended to convert liquid waste into solid form.
The DNFSB is requesting within 90 days from the date of the letter a report detailing the “technical basis” for the DOE’s approach to the possible seismic hazard analysis update. Connery requested that the document include five specific components, including the criteria for determining whether the lab requires a PSHA update; how a risk analysis “and/or seismic margin assessment” would be specifically applied to the Fuel Manufacturing Facility and Integrated Waste Treatment Unit, and how the results of that assessment would be applied in deciding whether to revise the PSHA; and the system for assessing the earthquake danger on a facility-wide basis.
The Idaho National Laboratory referred questions on the letter to DOE headquarters, which as of press time did not respond to requests for comment. DNFSB spokesman Andrew Thibadeau said DOE had not yet responded to the letter: “The letter has a 90-day reporting requirement and DOE has just received it.”
