ML20083E006

Suppl to 830919 Application to Amend Licenses DPR-57 & NPF-5,changing Tech Specs Re Scram Discharge Vol Closure Times

ML20083E006
Person / Time
Site:	Hatch
Issue date:	12/14/1983
From:	Head G GEORGIA POWER CO.
To:	Stolz J Office of Nuclear Reactor Regulation
Shared Package
ML20083E008	List: ML20083E006 ML20083E087
References
NED-83-607, TAC-53327, TAC-53328, NUDOCS 8312280398
Download: ML20083E006 (2)

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+ 4 ' '^ December 14, 1983 Director of Nuclear Reactor Regulation Attention: Mr. John F. Stolz, Chief Operating Reactors Branch No. 4 Division of Licensirg U. S. Nuclear Regulatory Commission Washirgton, D. C. 20555 NBC DOCKETS 50-321,50-36G OPERATI?G LICENSES DPR-57, NPF-5 EIMIN I. HA'ICH NUCIEAR PLANI' UNITS 1, 2 CHAN3E 'IO SDV TECHNICAL SPECIFICATION SUBMI' ITAL Gentlemen: l By letter of September 19, 1983, Georgia Power Company (GPC) proposed, pursuant to NRC requirements, Technical Specifications relating to operability of the Scram Discharge System. Based on model Technical Specifications provided, a 30 second closure time was included for closure of the Scram Discharge Volume (SDV) vent and drain valves (Technical Specification 4.1.6.1.c.1 for Unit 1 and 4.3.I.2.b.1 for Unit 2) .

Subsequent review has indicated that these valve closure times cannot be met for the Hatch design. We hereby propose a modification to our previous subnittal to lergthen these closure times.

The 30 second closure time is specified in the current version of BNR Standard Technical Specifications (STS). However, General Electric's design l specification for Hatch 1 and 2 did not include any closure time i requirements. IEB 80-17 Item 2 required licencees to measure SDV vent and drain valve closure times. Results of these tests, as provided to NRC by letters of July 28, 1980, July 30, 1980, and August 5, 1980, show maximum I closure times of 49.6 seconds for Unit 1 and 24.7 secondsi for Unit 2. While the Unit 1 closure time exceeds the value specified by the current version of STS, we have evaluated the consequences of longer closure times and have concluded that these times are acceptable. We therefore propose a Technical Specification value of 60 seconds for closure of the existing (inboard) valves for both units.

The effect of any delay in valve closure is that more water vill be i directed to the Clean Radwaste sump due to Control Rod Drive (CRD) seal leakage. Some of this water could flash and possibly cause airborne conditions. However, Unit 1 has operated with a closure time of l appr0ximately 49 seconds for several years without apparent problem. The drain sump capacity has been evaluated to be adequate to accanmodate the

maximum amount of scram discharge and CRD seal leakage prior to isolation at l 60 seconds or 120 seconds. We have therefore determined that use of these l values for the maximum permissible valve closure times will not adversely affect plant safety.

8312280398 831214 '00 PDR ADOCK 05000321 h P pop \y

GeorgiaPower A Director of Nuclear Reactor Regulation U. S. Nuclear Regulatory Caromission December 14, 1983 Page 2 Outboard SDV vent and drain valves are being installed to meet the NRC's requirement for redundant valves. GE specifications require these valves to open at least 5 seconds after the inboard valves. We propose a Technical Specification value of 120 seconds for closure of the outboard valves.

Since the inboard valves will isolate the SDV prior to 60 seconds after scram, the additional time required for the outboard valves to close will not result in additional discharges to the sump. The purpose of the redundant valves is to mitigate the possibility of an unisolable loss of coolant from the SDV. It is inportant that the outboard valves close, but the closure time is not crucial. We therefore believe the 120 second closure time is acceptable.

The Plant Review Board has reviewed the proposed change to the previous subnittal and determined that it does not constitute an unreviewed safety question. These modifications to our original submittal still represent NRC requirenents that are beyond those presently contained in the Technical Specifications. Therefore, the No Significant Hazards Analysis provided in the September 19, 1983 subnittal remains appropriate.

Enclosed are proposed Technical Specification pages to replace those contained in the September 19, 1983 submittal. Please contact this office if you desire additional information.

Pursuant to the requirements of 10 CFR 50.92, J. L. Ledbctter of the EnvirorYnental Protection Division of the Georgia Departnent of Natural Rescuces will be sent a copy of this letter and all applicable attachments.

G. F. Head states that he is Vice President of Georgia Power Company and is authorized to execute this oath on behalf of Georgia Power Company, and that to the best of his knowledge and belief the facts set forth in this letter are true.

GEDIGIA POWER COMPANY i

By: 9, b /

G. F. Head Sworn to and subscri before me this 14th day of December, 1983.

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C]']'f 4 /(1 , J Notary Public. Georgia, State at large My Commission Expires Sept.18,1987

~ N tary Public REB /rb Enclosure xc: H. C. Nix, Jr.

Senior Resident Inspector, Plant Hatch l J. P. O'Reilly, (NBC-Region II)

J. L. Ledbetter i

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