The use of probabilistic risk assessment in the safety assessment of Hanford nuclear facilities

The Probabilistic Risk Assessment of the Hanford Site started about 3 year ago. The first facility studied was the N Reactor. This paper reports on a limited-scope Probabilistic Risk Assessment that was completed in 1987 that showed the N Reactor met U.S. Nuclear Regulatory Commission Probabilistic Risk Assessment goals and its risk to the public was comparable to the commercial industry. An N reactor Level 3 Probabilistic Risk Assessment is under way and is scheduled for completion September 1989. The Level 1 phase is complete and results indicate a core damage frequency of 6.4 E-05/yr. A Fast Flux Test Facility Probabilistic Risk Assessment was started January 1989 and is due to be completed January 1992. Other major Probabilistic Risk Assessment activities are anticipated for the nonreactor facilities presently operating and planned at the Hanford Site