ML19294B510
| ML19294B510 | |
| Person / Time | |
|---|---|
| Site: | Peach Bottom  |
| Issue date: | 01/18/1980 |
| From: | Daltroff S PECO ENERGY CO., (FORMERLY PHILADELPHIA ELECTRIC |
| To: | Grier B NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION I) |
| References | |
| IEB-80-01, IEB-80-1, NUDOCS 8003040374 | |
| Download: ML19294B510 (3) | |
Text
.
S
.iy PHILADELPHIA ELECTRIC COMPANY 2301 M ARKET STREET P.O BOX 8699 PHILADELPHI A. PA.19101 R15) 8415001 sHIELos L., D Attnorg nacNc Pa 07crion January 18, 1980 Re: D ocke t N os.
50-277 50-278 IE Bulletin 80-01 Mr. B oy ce H.
Grier, Director Office of Inspection and Enforcement Region I United States Nuclear Regulat ory Commission 631 Park Avenue King of Prussia, PA 19406
Dear Mr. Grier:
This letter is in response to IE Bulletin 80-01, forwarded to us on January 14, 1980, concerning the operability of ADS valve pneumatic supply.
The " Action to be Taken by Licensees" and our responses are treated sequentially.
Action to be Taken by Licensee 1.
Determine if your facility has installed hard-seat check valves to isolate the ADS accumulator system f rom the pneumatic supply system.
Response
Hard-seat swing check valves (l" Power Model No. 2341) were installed to isolate the ADS accumulators from the non-safety Srade supply system.
These have been replaced with s of t-s eat,
spring-loaded check valves (l" NUPRO Model SS-16C4-1) to assure minimal leakage.
2.
Determine if periodic leak tests have been p erf ormed on y our ADS a c cu mu la t o r systems to assure emergency pneumatic supply 8003040
')
Mr. Boyce H.
Grier Page 2 for the FSAR-required number and du ra tion of valve operations.
Response
Prior to December 1979, leak tests had not been perf ormed on the ADS accumula t or sys tems.
When leak tests were performed and the significance of the results analyzed, the Peach Bottom Units were shut down, the check valves were replaced, and all p ortions of the accumulator systems were leak tested (check valves, piping, accumulators, solenoid valves, tubing, diaphragms).
With the new valves installed, the total leakage rate out of the accumulators was found to be between 0 and 10 sec/ min for all assemblies.
If a leakage of 10 sec/ min is assumed, calculations indicate that each ADS valve will be operable for the FSAR-specified minimum five actuations at atmospheric drywell p ressu re for in excess of 14 hours1.62037e-4 days <br />0.00389 hours <br />2.314815e-5 weeks <br />5.327e-6 months <br /> over a range of containment conditions which could be exp ected t o acc omp any the need for ADS operation.
The FSAR does not specify criteria for the du ra tion of the valve actuation capability.
Review seismic qualifications of the ADS pneumatic supply system:
a) from accumulator system isolation check valve t o ADS valve op erat or,
b) from isolation valve outside containment up to ADS accumulator check valve.
Response
a)
During the unit outages taken for check valve replacement, instrument air piping in the drywell was reviewed by Bechtel and PECO engineers to determine the extent and adequacy of seismic supports.
A total of two additional seismic supports were required to meet the seismic design criteria for the ADS accumulator systems (check valves through SRV actuator diaphragms).
b)
Seismic supports are not p rovided f or the ADS pneumatic supply from the is ola ti on value outside containment up to the ADS accumulator check valve, however, system operability is not affected because the ADS accumulator system is seismically qualified.
4.
Based upon determination of items 1,
2, and 3 above, evaluate op e r a bili ty of the ADS for the conditions under which it is required t o be op erable including a seismic
e O
Mr. B oy ce H.
Grier Page 3 event.
If operability cannot be established adhere to app rop ria te Technical Specification action statement.
Response
The results of a continuing detailed engineering evaluation being conducted by PECO and GE have thus far s h ow s that the modified ADS valve air supplies will p ermit ADS operation for all conditions for which it is required t o be op era ble.
5.
Provide an immediate notification to the NRC in the event the ADS is found to be operable.
Response
Immediate notification was provided to the NRC on January 10, 1980.
Very truly yours, I,
ll
)
4Ehyj'^
cc:
United States Nuclear Regulatory Commission Office of Inspection and Enforcement Division of Reactor Operations Inspection Washington, DC 20555