NRC Generic Letter 1980-04
| ML031350303 | |
| Person / Time | |
|---|---|
| Site: | Monticello  |
| Issue date: | 01/11/1980 |
| From: | James Keppler Office of Nuclear Reactor Regulation |
| To: | |
| References | |
| BL-80-001 GL-80-004, NUDOCS 8001280504 | |
| Download: ML031350303 (5) | |
G-go f Docket No. 50-263 1AN11 E8c Northern States Power Company ATTN: Mr. Dennis E. Gilberts Vice President Power Production and System Operation
414 Nicollet Mall Minneapolis, MN 55401 Gentlemen:
Enclosed is IE Bulletin No. 80-01 which requires action by you with regard to your BWR power reactor facility with an operating license.
Should you have questions regarding this Bulletin or the actions required of you, please contact this office.
Sincerely, James G. Keppler Director Enclosure: IE Bulletin No. 80-01 cc w/encl:
Mr. L. R. Eliason, Plant Manager Central Files Director, NRR/DPM
Director, NRR/DOR
Local PDR
John W. Ferman, Ph.D.,
Nuclear Engineer, HPCA
RI E RW
He s an/bk Keppler
1/11/80
8 00 1280 504
UNITED STATES SSINS No.: 6870
NUCLEAR REGULATORY COMMISSION Accessions No.:
OFFICE OF INSPECTION AND ENFORCEMENT 7912190652 WASHINGTON, D.C. 20555 January 11, 1980
IE Bulletin No. 80-01 OPERABILITY OF ADS VALVE PNEUMATIC SUPPLY
On January 10, 1980, the NRC was informed by Philadelphia Electric Company that engineering evaluation for Peach Bottom 2 and 3 has disclosed that the Automatic Depressurization System (ADS) pneumatic supply (either nitrogen or air) may not be operable for all possible events because of a combination of misapplication of check valve, a lack of leak testing of the accumulator system backing up each ADS valve operator and questions about the continued operability of the pneumatic supply in a seismic event. Attached is a simplified schematic of the pneumatic supply. The check valve nearest to the accumulator is a PAL, three-quarter inch, stainless steel, socket welded check valve with a hard seat (valve identification- B-1376 on the upper flange). Plant information at Peach Bottom shows substantial supports for the pneumatic supply inside the drywell, but seismic qualification has not been verified. The licensee has stated that the pneumatic supply is not seismically qualified outside the drywell.
Unit 2 was shutdown on 1/10/80 because of questions of ADS operability and Unit 3 has been provided a seismically qualified nitrogen supply at the containment penetration pending confirmation of seismic qualification of piping inside Unit 2 containment. The licensee is changing their valve to one with a soft seat to reduce leakage.
Actions to be taken by Licensees of GE BWR facilities with an operating license which use a pneumatic operator for ADS function:
1. Determine if your facility has installed hard-seat check valves to isolate the ADS accumlator system from the pneumatic supply system.
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.
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 accumulator check valve.
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.
IE Bulletin No. 80-01 January 11, 1980 5. Provide an immediate notification to the NRC in the event the ADS is found to be inoperable.
6. Provide a response in writing by January 18, 1980, for those facilities which use a pneumatic operator for ADS function.
Reports should be submitted to the Director of the appropriate NRC Regional Office and a copy should be forwarded to the U.S. Nuclear Regulatory Commission, Office of Inspection and Enforcement, Division of Reactor Operations Inspection, Washington, D.C. 20555.
Approved by GAO, B180225 (R0072); clearance expires July 31, 1980. Approval was given under a blanket clearance specifically for identified generic problems.
Attachment:
Sketch of ADS pneumatic supply
IE Bulletin No. 80-01 Enclosure January 11, 1980
RECENTLY ISSUED
IE BULLETINS
Bulletin Subject Date Issued Issued To No.
79-O1B Environmental Qualification 1/14/80 All power reactor of Class IE Equipment facilities with an OL
79-28 Possible Malfunction of 12/7/79 All power reactor Namco Model EA 180 Limit facilities with an Switches at Elevated OL or a CP
Temperatures
79-27 Loss Of Non-Class-1-E 11/30/79 All power reactor Instrumentation and facilities holding Control Power System Bus OLs and to those During Operation nearing licensing
79-26 Boron Loss From BWR 11/20/79 All BWR power reactor Control Blades facilities with an OL
79-25 Failures of Westinghouse 11/2/79 All power reactor BFD Relays In Safety-Related facilities with an Systems OL or CP
79-17 Pipe Cracks In Stagnant 10/29/79 All PWR's with an (Rev. 1) Borated Water System At OL and for information PWR Plants to other power reactors
79-24 Frozen Lines 9/27/79 All power reactor facilities which have either OLs or CPs and are in the late stage of construction
79-23 Potential Failure of 9/12/79 All Power Reactor Emergency Diesel Facilities with an Generator Field Operating License or Exciter Transformer a construction permit
79-14 Seismic Analyses For 9/7/79 All Power Reactor (Supplement 2) As-Built Safety-Related Facilities with an Piping Systems OL or a CP
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