ML20140B821

Forwards,For Info,Two Draft Repts Re Technical Insights Gained from Pras.Final Repts Will Be Published in Approx 2 Months.Comments Requested by 860224.W/o Encls

ML20140B821
Person / Time
Site:	Grand Gulf
Issue date:	01/22/1986
From:	Kintner L Office of Nuclear Reactor Regulation
To:	Kingsley O MISSISSIPPI POWER & LIGHT CO.
References
NUDOCS 8601270138
Download: ML20140B821 (3)

Text

. .

JAN 2 21986 Docket Nos. 50-416/417 . DISTRIBUTION

Docket File LKintner NRC PDR MDuncan Local POR ACRS (10)

Mr. Oliver J. Kingsley, Jr. PD#4 Reading Vice President, Nuclear Operations RBernero Mississippi Power & Light Company Ycung, OELD Post Office Box 23054 Edordan Jackson, Mississippi 39205 BGrimes JPartlow

SUBJECT:

REPORTS ON PRA INSIGHTS Enclosed are two draf t 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 informaticn in probabilistic. risk assessments regarding the factors which doninate 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 method focuses en areas which are sensitive to the results and the overall perception of plant weaknesses ard vulnera-bilities.

In particular, these reports contain discussions of: general insights cn plant strengths and weaknesses gained f rom PRAs; the contribution to core melt frequency fron 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 systens, components and events.

These reports will be published in their final forms in approximately two months. These reports are being provided to you, as well as all other licensees, in advance of formal publication for your information. If, after reviewing these reports, you wish to provide comments to the staff, please provide them by February 24, 1986.

Sincerely, Original Signeil by L. L. Kintner, Project Manager BWR Project Directorate No. 4 Division of BWR Licensing

Enclosures:

As stated

See next page PD#4/PM LKintner:lb 01/2.2/86 8601270130 860122 PDR ADOCK 05000416 P PDR

c#"% UNITED STATES P NUCLEAR REGULATORY COMMISSION 3

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,g WASHINGTON, D. C. 20555 e

%.....# JA'l2~ E Docket Nos. 50-416/417 Mr. Oliver J. Kingsley, Jr.

Vice President, Nuclear Operations Mississippi Power and Light Conpany

! P.O. Box 23054 Jackson, Mississippi 39205

SUBJECT:

REPORTS ON PRA INSIGHTS 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 numercus technical and managerial activities the information in probabilistic risk assessments 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 method focuses on areas which are sensitive to the results and the overall perception of plant weaknesses and vulnera-bilities.

In particular, these reports contain discussions of: general insights on plant strengths and weaknesses gained frcm PRAs; the contribution to core nelt 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 will be published in their final forms in approximately two mcnths. These reports are being provided to you, as well as all other licensees, in advance of formal publication for your information. If, after reviewing these reports, you wish to provide comnents to the staff, please provide them by February 24, 1986.

Sincerely, L. L. Kintner, Projec %t Manager BWR Project Directorate No. 4 Division of BWR Licensing

Enclosures:

As stated cc: Sec rext page

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Mr. Oliver D. Kingsley, Jr.

Mississippi Power & Light Ccmpany Grand Gulf Nuclear Steiton Cc' Robert B. McGehee, Esquire The Honorable William J. Guste, Jr.

Wise, Carter. Child, Steen and Caraway Attorney General P.O. Box 651 Department of Justice Jackson, Mississippi 39205 State of Louisiana Bator. Rcuse, Louisiana 70504 1

Nicholas S. Reynolds, Esquire Bishop, Liberman, Cook, Purcell and Reynolds i 5n .' 2b36 i Mr. Ralph T. Lally  :

Manager of quality Assurance Office of the Governor i Middle South Services, Inc. State of Mississippi l P.O. Box 61000 Jackson, Mississippi 39201

New Orleans, Louisiana 70161 Attorney General Mr. Larry F. Dale, Director Gartin building Nuclear Licensing and Safety Jackson, Mississippi 39205

i. Mississippi Power & Light Company P.O. Box 23054 hr. Jack McMillan, Director Jackson,flississippi 39205 Solid Waste Mississippi State Board of Health Mr. R. W. Jackson, Project Engineer 880 Lakeland Bechtel Power Corporation Jackson, Mississippi 39206 15740 Shady Grove Road Gaithersburg, Maryland 20877-1454 Alton B. Cobb, M.D.

i State Health Officer ltr. Ross C. Butcher State Board of Health Senior Resident Inspector P.O. Box 1700 U.S. Nuclear Regulatory Commissicn Jackson, Mississippi 39205 Route 2, Box 399 Port Gibson, Mississippi 39150 President Claiborne County Beard of Supervisors Regional Administrator, Region II Port Gibson, Mississippi 39150 U.S. Nuclear Regulatory Comission,

, 101 harit.tta Street, N.W., Suite 2900 Mr. Ted H. Cloninger Atlanta, Georgia 30323 Vice President, Nuclear Engineering and Support Mr. J. E. Cross Mississippi Power & Light Company Grand Gulf i;uclear Station Site Director Pcst Office Box 23054 Mississippi Power & Light Company Jackson,Iississippi 39205 P.O. Box 756 Port Gibson,1:ississippi 39150 1

Mr. C. R. Hutchinson GGNS General Manager i Mississippi Power & Light Company a Post Office Cox 7Ef l Fort Gibson, Mississippi 39150

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