ML19254F661
| ML19254F661 | |
| Person / Time | |
|---|---|
| Site: | Big Rock Point, Palisades File:Consumers Energy icon.png |
| Issue date: | 11/05/1979 |
| From: | James Keppler NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION III) |
| To: | Dewitt R CONSUMERS ENERGY CO. (FORMERLY CONSUMERS POWER CO.) |
| References | |
| NUDOCS 7911160207 | |
| Download: ML19254F661 (1) | |
Text
{{#Wiki_filter:b UNITED STATES E " 3,, g,j NUCLEAR REGULATORY COMMISSION
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REGION 111 o,%['\\/ [ 799 ROOSEVELT ROAD %...+ e GLEN ELLYN. ILLINOIS 60137 Docket No. 50-155 h a ;, I9b Docket No. 50-255 Consumers Power Company ATTN: Mr. R. B. DeWitt Vice President Nuclear Operations 212 West Michigan Avenue Jackson, MI 49201 Gentlemen: This Information Notice is provided as an early notification of a possibly significant matter. It is expected that recipients will review the infor-mation for possible applicability to their facilities. No specific action or response is requested at this time. If further NRC evaluations so indi-cate, an IE Circular, Bulletin, or NRR Generic Letter will be issued to recommend or request specific licensee actions. If you have questions regarding the matter, please contact the Director of the appropriate NRC Regional Office. Sincerely, wh& c ,JamesG.Kephr~ Director
Enclosure:
IE Information Notice No. 79-26 cc w/ enc 1: Mr. C. J. Hartman, Plant Superintendent Mr. J. G. Lewis, Manager Central Files Director, h% /DPM Director, NRR/ DOR PDR Local PDR NSIC TIC Ronald Callen, Michigan Public Service Commission Anthony Roisman, Esq., Attorney I347 .507 Myron M. Cherry, Chicago 7911160 2 0 )
SSINS: 6870 Accession No: 7908220133 UNITED STATES NUCLEAR REGULATORY COMMISSION OFFICE OF INSPECTION AND ENFORCEMENT WASHINGTON, D. C. 20555 November 5, 1979 IE Information Notice No. 79-26 BREACH OF CONTAINMENT INTEGRITY Description of Circumstances: On September 14, 1979, the Consumers Power Company (CPC) notified the NRC of diccovery at the Palisades Nuclear Generating Plant of a valve misalignment that had resulted in containment integrity being breached for an indeterminate length of time. While preparing to perform a Type "C" leak test between two manual valves in a 3" bypass line around the main 48" containment purge valve, plant personnel dis-covered that both of these manual isolation valves were locked in the open posi-tion. These valves should have been locked closed. Investigation by the licensee indicated that the valves may have been improperly positioned since April, 1978, when an efficiency test of the bypass line filters was performed. The plant has operated at power for the major portion of that tima period. The valve misalignment had no actual impact on the public health. However, in the event of a design basis accident wherein fuel damage and release of n* h'ev coolant inside the containment are postulated, the open valves would prt, side a significant path for a radioactive release from the containment. The initial design purpo.se for the bypass system was to provide a long term hydrogen contro basisaccident.-{capabilityforthecontainmentatmmherefollowingadesign It was intended that after approximately 30 days follywing an accident, when containment pressure and activity levels dropped sufficiently to permit venting, this system would be manuallv valved to vent the containment atmosphere, through high efficiency and charcoal filters, to the exhaubt stack. Thus the components in the bypass line beyond the two manual isolation valves were not designed for the severe service they would be exposed to with the valves open during the initial pressure surge of the design b.' sis accident, aid signif-icant uncontrolled release would result. High radiation in the vicinity of the bypass line would also make immediate closing of the manual isolation valves, even if identified as the source of leakcge, an extremely hazardous operation. The principal cause for this event was inadequacy of the procedures afdressing proper use and positioning of these valves. The master containment intearity valve line-up checklist, which is 1/ Current NRC requirements call DUPLICATE DOCUMENT hydrogen buildup. Palisades has i Entire document previously 1347 $08
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