ML17263A512
| ML17263A512 | |
| Person / Time | |
|---|---|
| Site: | Ginna  |
| Issue date: | 12/28/1993 |
| From: | Mecredy R ROCHESTER GAS & ELECTRIC CORP. |
| To: | Andrea Johnson NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM), Office of Nuclear Reactor Regulation |
| References | |
| REF-GTECI-A-46, REF-GTECI-SC, RTR-NUREG-1407, RTR-NUREG-CR-4334, TASK-A-46, TASK-OR GL-88-20, TAC-M83624, NUDOCS 9401110079 | |
| Download: ML17263A512 (5) | |
Text
REGULATORY INFORMATION DISTRIBUTION SYSTEM (RIDS)
ACCESSION NBR:9401110079 DOC.DATE: 93/12/28 NOTARIZED: NO FACIL:50-244 Robert Emmet Ginna Nuclear Plant, Unit 1, Rochester G
AUTH.NAME AUTHOR AFFILIATION MECREDY,R.C.
Rochester Gas 6 Electric Corp.
RECIP.NAME RECIPIENT AFFILIATION JOHNSON,A.R.
Project Directorate I-3
SUBJECT:
Provides listed info on plans to implement seismic aspects of GL-88-20,Suppl 4 re Reactor Coolant Sys structual integrity.
DISTRIBUTION CODE:
A011D COPIES RECEIVED:LTR ENCL SIZE:
TITLE: Generic Ltr 88-20 re Individual Plant Evaluations NOTES:License Exp date in accordance with 10CFR2,2.109(9/19/72)
DOCKET 05000244 05000244 RECIPIENT ID CODE/NAME PD1-3 PD INTERNAL: ACRS HOUSTON,M NRR/DORS/OEAB NRR/DRPE/PD1-4 NRR S
SPSB 01 RES SAIB RGN 2
RGN 4
EXTERNAL: NRC PDR COPIES LTTR ENCL RECIPIENT ID CODE/NAME JOHNSON,A AEOD/DSP/TPAB NRR/DORS/OTS B NRR/DRPW NRR/OGCB RES/DSIR/SAIB/B RGN 1 RGN 3
NSIC COPIES LTTR ENCL NOTE TO ALL"RIDS" RECIPIENTS:
PLEASE HELP US TO REDUCE WASTE! CONTACT THE DOCUMENT CONTROL DESK, ROOiVI Pl-37 (EXT. 20079) TO ELIMINATEYOUR NAME FROM DISTRIBUTION LISTS FOR DOCUMENTS YOU DON'T NEED!
TOTAL NUMBER OF COPIES REQUIRED:
LTTR 27 ENCL
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///////////I ROCHESTER GAS AND ELECTRIC CORPORATION o
89 EAST AVENUE, ROCHESTER N.K 14649-0001 ROBERT G MECREOY Vice President Cinna Nuciear Production December 28, 1993 TELEPHONE AREA CODE 71B 546 2700 U.S. Nuclear Regulatory Commission Document Control Desk Attn:
Allen R. Johnson Project Directorate I-3 Washington, D.C.
20555
Subject:
Generic Letter 88-20, Supp.
4 R.E.
Ginna Nuclear Power Plant Docket No. 50-244 Ref. (a):
Letter from A. Johnson (NRC) to R. Mecredy (RG&E), dated August 11,
- 1993,
Subject:
Review of Response to Generic Letter 88-20, Supplement 4
Individual Plant Examinations for External Events (TAC No. M83624)
Dear Mr. Johnson:
In order to facilitate future discussions, RG&E is providing the following information to NRC relative to our plans to implement the seismic aspects of Generic Letter 88-20, Supp.
4.
1.
We are in the process of determining if the Reactor Coolant System is able to maintain its structural integrity in the event of a 0.3g Review Level Earthquake (RLE).
Preliminary indications are that such a conclusion will be reached.
In that event, a seismically-induced small break LOCA will not be considered a credible event.
2.
Using the screening criteria of EPRI NP-6041-SL Rev.
1 and NUREG/CR-4334, we have determined that the containment and internal structures are able to withstand a 0.3g RLE.
3.
Based on our PRA being developed in response to Generic Letter 88-20, the frequency of a small break LOCA occurrence is less than 1.0 x 102/reactor year.
4.
Based on the EPRI seismic hazard
- curves, the frequency of a
>0.3g earthquake (RLE) is =5.5 x 10~/year.
This is expected to be very similar to the results from the revised Lawrence Livermore Laboratories seismic hazard curves.
Antici ated
Conclusion:
The probability of an RLE and a SBLOCA in the same year is less than 5
x 10B.
Since this is below the screening criteria of NUREG-1407 for reporting, we have determined that the sequence of events which would require evaluation of SBLOCA mitigation equipment should not be evaluated in our GL 88-20
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4 response.
The containment structure is also capable of withstanding the 0.3g RLE and its evaluation need not be performed for IPEEE.
Other safety-related equipment required to attain and maintain safe shutdown will be evaluated during RG&E's SQUG walkdowns as part of our resolution to USI A-46.
In addition to the data being provided to resolve USI A-46, RG&E will perform screening walkdowns for components on that Safe Shutdown Equipment List (SSEL),
and sort them into two categories:
1)
High Confidence Low Probability of Failure (HCLPF) greater than 0.3g and 2)
HCLPF less than or equal to 0.3g.
In the second category, RG&E willprovide the components'eismic margins beyond our currently licensed 0.2g SSE.
This will meet the main objective delineated in NUREG-1407:
to provide a
qualitative understanding of the effects of postulated severe accident scenarios.
The SQUG/IPEEE walkdowns will be performed by a team of experts who have the sophisticated engineering judgement necessary to determine the importance and potential consequences of seismically-induced failures on plant safety.
Included within their scope of review will be an assessment of non-seismic failures and human actions as they might affect Ginna Station's safe shutdown functions.
Our previously agreed upon schedule remains the same completion by May 22, 1995.
We are not aware of any other open issues regarding our commitments to GL 88-20, Supp.
4.
If so, any
- meetings, conference
- calls, or correspondence needed to resolve remaining IPEEE issues should be scheduled expeditiously in order to maintain this schedule.
Very truly yours, Robert C. Mecredy GJW5309 Attachment xc: Mr. Allen R. Johnson (Mail Stop 14D1)
Project Directorate I-3 Washington, D.C.
20555 U.S. Nuclear Regulatory Commission Region I 475 Allendale Road King of Prussia, PA 19406 Ginna Senior Resident Inspector
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