Response to Specific Questions on the Indian Point Probabilistic Safety Study

Pursuant to a congressional request, GAO reviewed the reliance placed on probabilistic risk assessment (PRA) techniques by the Nuclear Regulatory Commission. Particular emphasis was placed on the safety assessments performed at the Indian Point nuclear powerplants located close to New York City.

GAO stated that the Indian Point PRA is a comprehensive assessment which evaluates plant systems performance, the ability of the plant to contain radioactivity, and the consequences of potential accidents. While many analysts consider the Indian Point PRA to be the state-of-the-art in risk assessment, it suffers from the same fundamental problems as all PRA's: uncertainty and incomparability of results. Also, GAO concluded that, although the study identified the dominant contributors to risk, it did not identify the precise level of risk from operating the Indian Point nuclear powerplants.