ML20211H661
| ML20211H661 | |
| Person / Time | |
|---|---|
| Site: | Vermont Yankee File:NorthStar Vermont Yankee icon.png |
| Issue date: | 06/20/1986 |
| From: | Muller D Office of Nuclear Reactor Regulation |
| To: | Murley T NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION I) |
| Shared Package | |
| ML20209C518 | List:
|
| References | |
| FOIA-86-586 NUDOCS 8606250581 | |
| Download: ML20211H661 (2) | |
Text
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June 20, 1986 Docket No. 50-271 MEMORANDUM FOR:
Thomas E. Murley Regional Administrator Region I FROM:
Daniel R. Muller, Director BWR Project Directorate #2 Division of BWR Licensing
SUBJECT:
VERMONT YANKEE PRA ANALYSIS The Vermont Yankee Plant is one of a number of older plants for which we must consider technical knowledge gained since the plant was licensed (March 1972 for Vermont Yankee) in order to assure continued protection of the health and safety of the public.
One major concern is with regard to severe accidents. WASH-1400 used Probabilistic Risk Analysis (PRA) methodology to examine public risks from severe accidents from commercial nuclear power plants of the types then in use, and dealt specifically with the Peach Bottom plant as representative of Boiling Water Reactors (BWR's).
Following the issuance of WASH-1400 in 1975, PRA's were prepared for a number of plants, including several BWR's.
The results of all of these studies were considered when the Commission issued its Severe Accident Policy Statement on August 8, 1985. The statement concluded that, based on present knowledge, existing plants pose no undue risk to the public, and that there was no need for immediate action for these plants because of severe accident risk, however, the Commission stated that an examination of each existing plant was to be performed in order to search for significant risk contributors, or
" outliers". The staff has also worked together with an industry group, IDCOR (Industry Degraded Core Rulemaking Program), to develop a methodology less expensive and time consuming than a full PRA, whereby individual plants i
nevertheless could be examined to identify plant-specific vulnerabilities.
Following submittal of the IDCOR Program (expected later this year), the staff will review the methodology.
Upon approval, specific implementation would be required for plants such as Vermont Yankee.
In summary, while the Severe Accident Policy Statement has concluded that existing plants pose no undue risk to the public and that there is no need for immediate action, an examination of each plant will be done to search
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The development of the methodology for examining individual plants is nearing completion.
Following staff review and approval, this methodology will be applied to specific plants.
Ort;;inal slptei95, Daniel R. Muller, Director BWR Project Directorate #2 Division of BWR Licensing DISTRIBUTION:
Docket File VRooney SNorris RBernero Memo File n
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