ML20154M347
| ML20154M347 | |
| Person / Time | |
|---|---|
| Site: | Prairie Island  |
| Issue date: | 03/07/1986 |
| From: | Lear G Office of Nuclear Reactor Regulation |
| To: | Musolf D NORTHERN STATES POWER CO. |
| References | |
| NUDOCS 8603140087 | |
| Download: ML20154M347 (3) | |
Text
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MAR 0 71986 Docket Nos.: 50-282 and 50-306 Mr. D. M. Musolf Nuclear Support Services Dept.
Northern States Power Company 414 Nicollet Mall - 8th Floor Minneapolis, Minnesota 55401
Dear Mr. Musolf:
SUBJECT:
REPORTS ON PRA INSIGHTS - (PRAIRIE ISLAND UNITS 1 AND 2)
Enclosed are two draft reports concerning technical insights gained from Probabilistic Risk Assessments (PRAs). These reports are the outcome of an ongoing effort to make available and utilize in numerous technical and managerial activities the information in PRAs regarding the factors which dominate the risk associated with nuclear power plants. This effort includes identification of the features of design or operational practices which have been found to be important to safety in the types of plants which have been subjected to risk assessments.
In addition, the section on insights into PRA methodologies focuses on areas which are sensitive to the results and the overall perception of plant weaknesses and vulnerabilities.
In particular, these reports contain discussions of:
general insights on plant strengths and weaknesses gained from PRAs; the contribution to core melt frequency from classes of sequences induced by various initiating events; modifications, both hardware and procedural, which have been implemented to address problems identified in the conduct or as a result of PRAs; insights into PRA methodologies; and the contribution to measures of risk (core melt frequency and consequences of radioactive releases) from systems, components and events.
These reports are being provided to you, as well as all other licensees, in advance of formal publication for your information.
Your comments and suggestions are welcome on these reports.
Sincerely, George E. Lear, Director Project Directorate #1 Division of PWR Licensing-A
Enclosures:
As Stated cc: w/o Enclosures See Next Page PM/ PAD #1p/hPD/ PAD #1 Office:
LA/ PAD #1 Ek Surname:
PShuttlew N DDilanni/tg Glear Date:
03/5/86 03/j786 03/ V/86 8603140007 860307 DR ADOCK 05000282 p
Mr. D. M. Musolf Prairie Island Nuclear Generating Northern States Power Company Plant cc:
Gerald Charno-ff, Esq.
Shaw, Pittma, Potts and Trowbridge 1800 M Street, NW Washington, DC 20036 Executive Director Minnesota Pollution Control Agency 1935 W. County Road, B2 Roseville, Minnesota 55113 Mr. E. L. Watzl, Plant Manager Prairie Island Noclear Generating Plant Northern States Power Company Route 2 Welch, Minnes~ota 55089 Jocelyn F. Olson, Esq.
Special Assistant Attorney General Minnesota Pollution Control Agency 1935 W. County Road, B2 Roseville, Minnesota 55113 U.S. Nuclear Regulatory Comission Resident Inspector's Office Route #2, Box 500A Welch, Minnesota 55089 Regional Administrator, Region III U.S. Nuclear Regulatory Comission Office of Executive Director for Operations 799 Roosevelt Road Glen Ellyn, Illinois 60137 Mr. William Miller, Auditor Goodhue County Courthouse Red Wing, Minnesota 55066
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?k NRC PDR Local'PDR Glear OELD E. Jordan B. Grimes J. Partlow.
D..Dilanni PShuttleworth ACRS (1)
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