ML19294B680
| ML19294B680 | |
| Person / Time | |
|---|---|
| Site: | Vermont Yankee File:NorthStar Vermont Yankee icon.png |
| Issue date: | 01/18/1980 |
| From: | Moody D VERMONT YANKEE NUCLEAR POWER CORP. |
| To: | Grier B NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION I) |
| References | |
| IEB-80-01, IEB-80-1, NUDOCS 8003050293 | |
| Download: ML19294B680 (2) | |
Text
a nte P4s VERMONT Y AN KEE NUCLEAR POWER CORPORATION SEVENTY SEVEN GROVE STREET B.4.1.1 RUTLAND YERMONT 05701 WVY 80-14 RE PLY TO:
January 18, 1980 ENGINEERING OFFICE TURNPIKE RO Ao WESTBORO M ASS ACHUSETTS 01581 United States Nuclear Regulator / Commission Region I 631 Park Avenue King of Prussia, PA 19406 Attention:
Office Of Inspection and Enforcement Mr. Boyce H. Grier, Director
References:
(1)
License No. DPR-28 (Docket No. 50-271)
(2)
USNRC Letter to VYNPC dated January 11, 1980; IE Bulletin 80-01, Operability of ADS Pneumatic Supply
Dear Sir:
Subject:
Response to IE Bulletin 80-01 Reference (2) requested that licensees of GE BWR facilities provide information related to the pneumatic supply system (s) used for ADS oper-ation. Vermont Yankee's responses to the specific questions are as
[
follows-1.
Determine if your facility has installed hard-seat check valves to isolar.e the ADS accumulator system from the pneumatic supply system.
Response
The " equivalent" valves used at Vermont Yankee are 1"-600i/ balted cap renewable seat check valves manufactured by Hancock.
The seat material is stainless steel with Stellite facing.
2.
Determine if periodic leak tests have been performed on your ADS accumulator systems to assure emergency pneumatic supply for the FSAR-required number and duration of valve operations.
Response
The ADS accumulator systems are not periodically leak tested.
3.
Review seismic qualifications of the ADS pneumatic supply system:
(a) from accumulator system isolation check valve to ADS valve
- operator, (b) from isolation valve outside containment up to ADS accu-dator check valve.
C 8003050
United States Nuclear Regulatory Commission January 18, 1980 Mr. Boyce H. Grier, Director Page 2
Response
The sections of pneumatic supply piping discussed above have been verified to be seismically qualified.
4.
Based upon determination of items 1, 2, and 3 above, evaluate operability of the ADS for the conditions under which it is required to be operable including a seismic event.
If operability cannot be established adhere to appropriate Technical Specification action statement.
Response
Vermont Yankee has evaluated the ADS system, including the pneumatic supply and concludes that, based on available information, continued operation is justified.
This determination is based on information contained in Responses 1, 2, and 3 as well as the following:
(a) Vermont Yankee utilizes the station instrument air system to provide the ADS accumulators and valves with a continuous supply of compressed air.
This is unlike the situation at Peachbottom where their pneumatic (nitrogen) supply system isolates under certain accident conditions and ADS valve operation is dependent only on accumulator reserves.
(b) The lift check valves used at Vermont Yankee, although hari seated, are not the same as the PAL valves used at Peachbottom. We feel that this difference is significant enough to preclude equating the swing check valve problem at Peachbottom to Vermont Yankee.
In summary, based on the points made above (seismically qualified piping, station instrument air supply and "alve differences) we feel confident that the ADS valves at Vermont Yankee will operate when required.
We plan to inspect the ADS pneumatic supply system during the NUREG 0578 outage scheduled to commence on February 16, 1980.
If it is determined that system operation can be improved, changes will be made at that time.
We trust that the above supplied information adequately addresses the concerns contained in Reference (2); however, should you desire any additional information, do not hesitate to call.
Very truly yours, VERMONT YANKEE NUCLEAR POWER CORPORATION
~
D. E. Moody Manager of Operations RJW/sec