RBG-37494, Updates 891027 Initial Response to GL 88-20 Re IPE, Consisting of Revised Completion Dates for Milestones.Level 1 & 2 IPE Submittals,Per GL 88-20,Suppls 1,2 & 3,will Be Submitted by 930201

Updates 891027 Initial Response to GL 88-20 Re IPE, Consisting of Revised Completion Dates for Milestones.Level 1 & 2 IPE Submittals,Per GL 88-20,Suppls 1,2 & 3,will Be Submitted by 930201

ML20118A634
Person / Time
Site:	River Bend
Issue date:	09/15/1992
From:	Odell W GULF STATES UTILITIES CO.
To:	NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM)
References
GL-88-20, RBG-37494, NUDOCS 9209240249
Download: ML20118A634 (2)

Text

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. e s GULF STATES UTILITIES COMPANY '"

M(4 M W h!@D 4 PO5T Of f tCt SQr 27ft StFRANDS?l[ L OLitSt ANA ?Q F 76 Awi A (00F $04 6M 8.ON 346 B0t t September 15,1992 RBG. 37494 Fi; 7 Nos. G9.5, G9.33.4 U.S. Nuclear Regulatory Commission Document Control Desk Washington, D.C. 20555 Gentlemen:

River Bend Station - Unit 1 NRC Generic Letter 88-20 Individual Plant Examination Docket No. 50-458 This letter updates Gulf States Utilities Company's-(GSU) initial response to Generic Letter 88 20 dated October 27, 1989. In the initial response GSU outlined the schedule for completing the Individual Plant Examination (IPE) for River Bend Station (RBS), providing expected completion dates for milestones.

These dates have been revised due to several factors discussed below.

The October 27, 1989 letter stated that the IPE would be based on the configuration of the plant as it existed on March 1,1989, and that significant changes to the plant after that date would be incorporated into the IPE subsequent to the initial submittal of the Ixvel 1 Probabilistic Risk Assessment (PRA) results.

In order to make the Level 1 IPE as current as possible, approximately 350 plant modifications implemented from January 1,1988 through April 1,1991 were screened and incorporated as applicable. In addition, a number of plant modifications from a recent extended refueling outage .were also reviewed for incorporation into the IPE. The most significant of these is a new " closed loop" normal service water system. These extensive modeling changes increased the length of the IPE process.

Also, GSU established an in-house group to perform the IPE in an effort to maintain utility involvement. However, developing this in-house PRA expertise has taken longer than anticipated. This process was further delayed by the loss.

of a key Level 1 analyst. Lastly, the PRA group is a support organization and has been tasked with performing safety assessments for a variety of other projects -

at RBS, as well as developing responses to other severe accident issues (e.g.,

station blackout).

9209240249 920915 PDR .ADOCK 05000458 IF

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For the reasons described above, GSU has revised the IPE schedule as follows:

February 1,1993 _

Ixvel 1 and Ixvel 2 IPE submittal to meet GL 88-20 and supplements 1, 2, and 3 August 1,1993 -

Submittal of detailed Level 1 and Level 2 PRAs for risk-based irgulatory use .

Should you have any questions or require additional information, please contact Mr. L.L. Dietrich at (504) 381-4866.

Sincerely, af%LL h W.H. Odell T Manager - Oversight River Bend Nuclear Group LAFJ /JS i /[C5 (q Attachment c cc: U.S. Nuclear Regulatory Commission 611 Ryan Plaza Drive, Suite 400 Athc.gton, TX 76011 D. V. Pickett U.S. Nuclear Regulatory Commission One White Flint North 11555 Rockville Pike

'ockville, MD 20852 NRC Resident Inspector P.O. Box 1051 St. Francisville, LA 70775

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