ML20077G960
| ML20077G960 | |
| Person / Time | |
|---|---|
| Site: | Hatch  |
| Issue date: | 07/28/1983 |
| From: | Beckham J GEORGIA POWER CO. |
| To: | Stolz J Office of Nuclear Reactor Regulation |
| References | |
| RTR-NUREG-0737, RTR-NUREG-737, TASK-2.K.3.18, TASK-TM NED-83-398, TAC-45691, TAC-45692, TAC-57309, NUDOCS 8308090478 | |
| Download: ML20077G960 (2) | |
Text
, o Georgia Power Company 333 P.edmont Avenue Atlanta. Georgia 30308 Telephone 404 526-7020
. Maihng Address-Post Offce Box 4545 Atlanta, Georgia 30302 Georgia Power the southem electrc system J. T. Beckham, Jr.
Vice President and General Manager gg,gy,)gg Nuclear Gerierat!on July 28, 1983 Director of Nuclear Reactor Regulation Attention: Mr. John F. Stolz, Chief.
Operating Reactors Branch No. 4 Division of Licensing U. S. Nuclear Regulatory Commission Washington, D. C.
20555 NRC DOCKETS 50-321, 50-366 OPERATING LICENSES DPR-57, NPF-5 EDWIN I. HATCH NUCLEAR PLANT UNITS 1, 2 NUREG-0737 ITEM II.K.3.18: MODIFICATION OF ADS LOGIC Gentlemen:
In response to NUREG-0737 Item II.K.3.18, the BWR Owners Group performed a study of alternatives to the current ADS actuation logic which would eliminate the need for manual actuation to ensure adequate core cooling.
Georgia Power Company (GPC) has been a participant in this effort.
In the NRC staff's Safety Evaluation of the Owners Group study two' options were identified as acceptable: (1) elimination of the high drywell pressure permissive and addition of a manual inhibit switch, and (2) bypass of the high drywell pressure permissive after a sustained low water level and addition of a manual inhibit switch.- By your letter of June 3,1983, GPC was requested to choose one of the two acceptable modifications for implementation at Plant Hatch, provide a schedule for implementation, and propose appropriate Technical Specifications.
In response to this request GPC proposes to implement the second option at Plant Hatch Units 1 and 2 provided that the required bypass timer setting provides a significant margin above the two minute delay in the current ADS logic. GPC considers this margin necessary to-protect against a spurious ADS actuation.
An analysis to determine this setting has been initiated and the results will be available at a later date.
The modifications will be implemented during the first refueling outage following completion of design and parts procurement.
We expect that implementation will take place in Unit 1 during the refueling outage following cycle 7, currently scheduled for 1985, and in Unit 2 during the refueling outage following cycle 5,
currently scheduled for 1985.
8 L
i 8300090478 830728 8 0 PDR ADOCK 05000321 p
Georgia Power A Director of Nuclear Reactor Regulation Attention:
Mr. John F. Stolz, Chief Operating Reactors Branch No. 4 July 28, 1983 Page Two Proper operation of the ADS will be assured by plant procedures and Technical Specifications which will be revised to reflect the logic modification.
The bypass timer setting will-be added to lkilt 1 Technical Specification 3/4.2 and to Unit 2 Technical Specification 3/4.3.3.
Limiting Conditions for Operation and Surveillance Requirements will be consistent with those specifled for the current ADS timer.
Proper function of the manual inhibit switch will be assured by ADS logic system functional tests which are required by Unit 1 Technical Specification 3/4.5.F and Unit 2 Technical Specification 3/4.5.2.
Use of the manual inhibit switch will be addressed in emergency procedures.
Protection against inadvertent manual inhibit of the ADS will be provided by the use of a keylock switch, an annunciator which will actuate with the switch in the " inhibit" position, and by operating procedures which will require that correct switch position be verified at least once per shift.
Please contact this office if there are any cuestions.
Very truly yours,
([
L J. T. Beckham, Jr.!
JH/mb xc:
J. T. Beckham, Jr.
H. C. Nix, Jr.
J. P. O'Reilly (NRC-Region II)
Senior Resident Inspector 700775