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 PDR Local PDR NSIC TIC 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 and a copy should of Inspection and Washington, D.C.submitted to the Director of the appropriate NRC Regional Office be forwarded to the U.S. Nuclear Regulatory Commission, Office Enforcement, Division of Reactor Operations Inspection, 20555.Approved by GAO, B180225 (R0072); clearance expires July 31, 1980.given under a blanket clearance specifically for identified generic Approval was problems.Attachment:
Sketch of ADS pneumatic supply IE Bulletin January 11, No. 80-01 1980 Enclosure RECENTLY ISSUED IE BULLETINS Bulletin No.79-O1B Subject Environmental Qualification of Class IE Equipment Date Issued 1/14/80 Issued To All power reactor facilities with an OL 79-28 79-27 79-26 79-25 Possible Malfunction of Namco Model EA 180 Limit Switches at Elevated Temperatures Loss Of Non-Class-1-E
Instrumentation and Control Power System Bus During Operation Boron Loss From BWR Control Blades Failures of Westinghouse BFD Relays In Safety-Related Systems Pipe Cracks In Stagnant Borated Water System At PWR Plants Frozen Lines Potential Failure of Emergency Diesel Generator Field Exciter Transformer
12/7/79 11/30/79 11/20/79 11/2/79 10/29/79 9/27/79 9/12/79 All power reactor facilities with an OL or a CP All power reactor facilities holding OLs and to those nearing licensing All BWR power reactor facilities with an OL All power reactor facilities with an OL or CP All PWR's with an OL and for information to other power reactors All power reactor facilities which have either OLs or CPs and are in the late stage of construction All Power Reactor Facilities with an Operating License or a construction permit 79-17 (Rev. 1)79-24 79-23 79-14 (Supplement
2)Seismic Analyses For As-Built Safety-Related Piping Systems 9/7/79 All Power Reactor Facilities with an OL or a CP
i A A Fm a -- --ADS Valve N DryweLL WaLL VI A< ,t f>A- _ _ wo-l~