ML20154M388
| ML20154M388 | |
| Person / Time | |
|---|---|
| Site: | Sequoyah  |
| Issue date: | 03/05/1986 |
| From: | Youngblood B Office of Nuclear Reactor Regulation |
| To: | White S TENNESSEE VALLEY AUTHORITY |
| References | |
| NUDOCS 8603140173 | |
| Download: ML20154M388 (3) | |
Text
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Docket Nos. 50-327 and 50-328 l@R 0 51986 Mr. S. A. White Manager of Nuclear Power Tennessee Valley Authority 6N 38A Lookout Place 1101 Market Street Chattanooga, Tennessee 37401-2801
Dear Mr. White:
Subject:
Reports on PRA Insights - Sequoyah 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 frequenr.y from classes of sequences induced by various initfating events; modifications, both hardware and procedural, which have been implemented to address preblems identified in the conduct or as a result of PRAs; insights i
into PRA rethodologies; 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 contrents and suggestions are welcome on these reports.
Sincerely, Original cir,noi bf 3
/
D. Hood 3 B. J. Youngblood, Director F
PWR Project Directorate 44 Division of PWR Licensing-A, NRR
Enclosures:
/s stated l
cc w/o enclosure:
See next page p.5f1 fn PWR#fdWR-A PWS#M.0PWR-A PWR#4:DPWR-A M0bricE:kab CStdhle BJYoungblood 03/{/86 03/ C /86 03/g /86
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MAR 0 51986 9
Mr. H. G. Parris Tennessee Valley Authority Sequoyah Nuclear Plant cc:
Herbert S. Sanger, Jr., Esq.
Tennessee Department of Public General Counsel Health Tennessee Valley Authority ATTN: Director, Bureau of 400 West Sunnit Hill Drive, E 118 33 Environmental Health Services Knoxville, Tennessee 37902 Cordell Hull Building Nashville, Tennessee 37219 Mr. K. W. Whitt Mr. Michael H. Mobley, Director Tennessee Valley Authority Division of Radiological Health 400 West Sunnit Hill Drive E3A8 T.E.R.R.A. Building Knoxville, Tennessee 37902 150 9th Asanue North Nashville, Tennessee 37203 Mr. Bob Faas Westinghouse Electric Corp.
County Judge P.O. Box 355 -
Hamilton County Courthouse Pittsburgh, Pennsylvania 15230 Chattanooga, Tennessee 37402 Mr. Jerrj Wils Tennessee Valley Authority SN 133 Lookout Pisce Chattanooga, Tennessee 37402-2801 Mr. Donald L. Williams, Jr.
Tennessee Valley Authority 400 West Sunnit Hill Drive W10885 Knoxville, Tennessee 37902 Resident Inspector /Sequoyah NPS c/o U.S. Nuclear Regulatory Connission 2600 Igou Ferry Road Soddy Daisy, Tennessee 37379 Regional Administrator, Region II U.S. Nuclear Regulatory Connission, 101 Marietta Street, N.W., Suite 2900 Atlanta, Georgia 30323
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