ML20205Q246

Forwards Rev 0 to 10CFR50 & App R Exemption Requests. Encl Discusses Addl Exemptions Needed as Result of Reanalysis to Incorporate Generic Ltr 85-01 Guidance.Reanalysis Will Be Incorporated Into Updated Fire Hazards Analysis

ML20205Q246
Person / Time
Site:	Hatch
Issue date:	05/16/1986
From:	Gucwa L GEORGIA POWER CO.
To:	Miller D, Muller D Office of Nuclear Reactor Regulation
Shared Package
ML20205Q251	List: ML20205Q246
References
0435C, 435C, GL-83-33, GL-85-01, GL-85-1, SL-502, TAC-61626, TAC-61627, NUDOCS 8605280223
Download: ML20205Q246 (4)

Text

Georgia Fbwsr Company 333 Piedmont Avenue .

e n 4 526 "6 -

Of ox 545 Atlanta, Georgia 30302 GeorgiaPower L T. Guews r?e southem etoc sptm Manager Nuclear Safety and Licensing 0435C May 16, 1986 Director of Nuclear Reactor Regulation Attention: Mr. D. Muller, Project Director BWR Project Directorate No. 2 Division of Boiling Water Reactor Licensing U.S. Nuclear Regulatory Commicsion Washington, D.C. 20555 NRC DOCKETS 50-321, 50-366 OPERATING. LICENSES DPR-57, NPF-5 EDWIN I. HATCH NUCLEAR PLANT-UNITS 1 AND 2 10 CFR 50.48 AND APPENDIX R EXEMPTION REQUESTS Gentlemen:

. As mentioned in previous correspondence, a reanalysis was to be performed to confirm the original safe shutdown analysis contained in the Georgia Power Company (GPC) " Response to 10 CFR 50.48 and Appendix R" originally submitted in July 1982. This reanalysis was performed to incorporate additional guidance from the - NRC contained in Generic Letter 85-01 and from the NRC Regional Workshops held in the spring of 1984, as well as plant modifications required to resolve other NRC concerns not related to the requirements of 10 CFR 50.48 and Appendix R. This reanalysis is now complete and represents an extension of the analysis beyond that _ which was performed for the original submittal. The results of this reanalysis are being incorporated into an updated Fire Hazards Analysis (FHA). This updated FHA is currently in a review stage and will be submitted on July 22, .1986, coincident with the updated FSAR submittal date. The purpose of this letter is to request the additional exemptions needed as a result of the reanalysis.

FHA REANALYSIS The " Response to 10 CFR 50.48 and Appendix R" submittal for Plant Hatch will be superseded when the updated FHA is issued. For the review of this submittal, Chapters 1, 2, and 5 are unchanged by the reanalysis. Chapter 3, which is the safe shutdown pathway evaluation, has been slightly revised as a result of the reanalysis. The revised safe shutdown pathway evaluation is detailed in the safe shutdown analysis and will be summarized in the updated 8605280223 860516 PDR ADOCK 05000321 F PDR L

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Georgia Powerkn Director of Nuclear Reactor Regulation Attention: Mr. D. Muller, Project Director BWR Project Directorate No. 2 May 16, 1986 Page Two FHA. The safe shutdown analysis presented in Chapter 4 remains generally the same. The area descriptions and fire protection systems for each fire area will be detailed in the updated FHA. The safe shutdown analysis and modifications required for compliance are detailed in the actual analysis for each fire area. The exemptions previously requested and granted have been reviewed to ensure that their basis is still valid. The enclosure to this letter discusses the significant changes which have been made to the information presented in Chapter 4. In some cases, modifications which were identified in Chapter 4 have changed. The modifications which are required for compliance are detailed in the actual analysis for each fire area and are not specifically addressed in this letter.

For the Appendix R Fire Protection reanalysis, General Electric Company was requested to reevaluate the performance of the plant and the systems required for safe shutdown and to incorporate the addition of the low-low set relief logic to the Safety Relief Valve (SRVs), the lowering of the water level trip for the Main Steam Isolation Valves (MSIVs) from level 2 to level 1, the logic modifications for the automatic depressurization system, and the raising of the setpoint for level 1.

Changes have also been made to the safe shutdown systems and the components list previously submitted. The changes to this list have been made for various reasons as a result of the Appendix R reanalysis and plant modifications. The methodology used to determine which components should appear on this list has not changed from that in the July 1982 submittal.

However, more recent NRC guidance has necessitated the assumption of various additional scenarios which have resulted in the need to add and delete components from this list.

All of the fire area boundaries were reevaluated with respect to their fire ratings, the pathway in each area used for shutdown, the location of safe shutdown components, and general fire protection safety. As a result, some of the fire area boundaries have changed from previous submittals. Al so ,

boundaries which are not completely sealed, which are n?t floor-to-ceiling 3-hour-rated barriers, and for which exemptions have not been previously requested have been identified.

TECHNICAL EXEMPTIONS The reanalysis has identified new technical exemptions which are needed.

These technical exemption requests are discussed in Section 1 of the enclosure to this letter. Because of conflicts between Generic Letter 83-33 and the draft guidance contained in Generic Letter 85-01 regarding fire area boundaries, GPC is requesting a generic exemption for fire area boundaries 0435C t am

Georgia Powerkh Director of Nuclear Reactor Regulation Attention: fir. D. Muller, Project Director BWR Project Directorate No. 2 May 16, 1986 Page Three which are not currently rated but can be justified as being adequate by a fire hazards analysis. This exemption request is discussed in Section 1.1 of the enclosure to this letter. Drawings which show the fire areas and their boundaries are also enclosed. A review of previously granted exemptions identifies areas which could be misunderstood or misinterpreted. These exemptions are discussed in Section 2. We have attempted to identify the area needing clarification, explain the reason for the clarification and restate the exemption in a more specific manner. This is being dcne to avoid any misunderstandings at a later date.

SCHEDULAR EXEMPTIONS Section 3 is a request for schedular extension under 10 CFR 50.12 for specific pieces of equipment which may not be installed before our currently scheduled implementation deadline of November 30, 1986 All of the modifications which can be completed before November 30, 1986, will be completed. However, circumstances beyond GPC's control may prevent the completion of some modifications in both units.

TECHNICAL REVISIONS The combustible fire loadings for all fire areas have also been reevaluated.

The combustible loadings for some areas have changed. Most of the changes in the combustible loadings are not significant. In Table 4.2-1 of the enclosure to this letter, the new fire loadings for all areas with previously granted exemptions are compared to the fire loadings listed in previous submittals.

For areas where an exemption was granted on the basis of a low combustible loading but the calculated combustible loading has increased, the effect of the increase has also been addressed in Section 4 The control room and cable spreading room have also been reanalyzed for the Appendix R fire as part of the overall plant reanalysis. Additional technical exemptions associated with the remote shutdown system are also being requested in Section 1. As a result of the extensive modifications performed for the installation of the analog transmitter trip system ( ATTS), the shutdown for a fire in the computer room will now be performed from the remote shutdown panel s. This need was not originally anticipated. However, because of the extensive circuit routing through this room, the protection of one pathway of shutdown circuits within the computer room is not practical . Shutdown using the remote shutdown system will now be accomplished for a fire in the control room, the cable spreading room, or the computer room.

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E GeorgiaPower d Director of Nuclear Reactor Regulation Attention: Mr. D. Muller, Project Director BWR Project Directorate No. 2 May 16, 1986 Page Four There is one modification area which is being changed and is addressed in Section 4. The change is related to the specific type of fire detection device to use in a given area. The previous GPC submittals and NRC-issued Safety Evaluation Reports (SERs) indicated the particul ar type of fire detection devices to be installed in certain areas of the plant. However, because of deficiencies cited in the existing detection systems and the increasing unavailability of parts for the existing systems, a complete reevaluation of the plant fire detection systems was performed. This reevaluation was performed utilizing a design philosophy which considered current state-of-the-art fire detection technology and an analysis of each fire area at Plant Hatch to determine the most appropriate type of detector to use and the most appropriate placement of the detectors. Therefore, the particular type of detector used in a given area may be different from that previously identified. The most appropriate type of detector, as justified by a fire protection engineer, will _ be used in each area of the plant. The net effect of these changes will be to improve the overall plant fire protection above that which is currently installed or indirectly committed to in previous correspondence.

Because of the major cost and effort involved in complying with 10 CFR 50.48 and Appendix R,.your timely review of this letter is requested. Should you have any questions, or require addic.onal information, please contact this office. ,

Sincerely,

/f~4 w

, L. T. Gucwa JDH/lc Enclosures ,

c: Georgia Power Company ' Nuclear Regulatory Commission Mr. i. P. O'Reilly Dr.,J. N. Grace, Regional Administrator Mr. J. T. Beckham, Jr. Senior Resident Inspector Mr. H. C. Nix, Jr.

GO-NORMS 0435C 700775