ML19254F680
| ML19254F680 | |
| Person / Time | |
|---|---|
| Site: | Comanche Peak  |
| Issue date: | 11/05/1979 |
| From: | Seyfrit K NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION IV) |
| To: | Gary R TEXAS UTILITIES ELECTRIC CO. (TU ELECTRIC) |
| References | |
| NUDOCS 7911160260 | |
| Download: ML19254F680 (1) | |
Text
{{#Wiki_filter:C UNITED STATES /pa a:c,#'o, o NUCLEAR REGULATORY COMMISSION @ 's / '$ REGloN IV j' i o 611 RY AN PL AZA DRIVE, SUITE 1000 N,,:,yj r' ARLINGTON, TEXAS 76012 5 / +... November 5, 1979 In Reply Refer To: RIV Docket Nos. 50-445/IE Information Notice No. 79-26 50-446/IE Information Notice No. 79-26 Texas Utilities Generating Company ATTN: Mr. R. J. Gary, Executive Vice President and General Manager 2001 Bryan Tower Dallas, Texas 75201 Gentlemen: This IE Infotaation Notice is provided as an early notification of a possibly significant matter. It is expected that recipients will review the information for possible applicability to their facilities. No specific action or response is requested at this time. If further NRC evaluations so indicate, an IE Circular, IE 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, h[V.Seyfritk4/ b( Kar Director
Enclosures:
1. IE Information Notice No. 79-26 2. List of IE Information Notices Issued in the Last Six Months 1351 289 7 9111601(,C)
SSINS: 6870 Accession No: 7908220133 UNITED STATES NUCLEAR REGULATORY COMMISSION OFFICE OF INSPECTION AND ENFORCEMENT WASlIINGTON, D. C. 20555 IE Information Notice No. 79-26 Date November 5,1979 Page 1 of 2 BREACH OF CONTAINMENT INTEGRITY Description of Circumstances: On Septem5er 14, 1979, the Consumers Power Company (CPC) notified the NRC of discovery at. the Palisades Nuclear Generating Plant of a valve misalignment t ha t. 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 aree the main 48" containment purge valve, plant personnel dis-covered that both et tt se manual isolation valves were locked in the open posi-tion. These vai- :s w.uia nove been locked closed. Investigation by the licensee indicated that tL have been improperly positioned since April, 1973, a y when a: efficiency test of the hypass line filters was performed. The plant has operated at power for the major portion of that time period. The valve misalignment had no actual impact on the public health. Iloweve r, in the event of a design basis accident wherein fuel damage and release of primary coolant inside t he containment are postulated, the open valves would provide a significant path for a radioactive rnlease from the containment. The initial design pny.ase for the ' ypass system was to provide a long-term basisaccident.-{capabilityforthecontainmentatmosphere hydrogen contro following a design It was intended that after approximately 30 days following an accident, when containment pressure and activity levels dropped sufficiently to permit venting, this system would be manually valved to vent the containment atmosphere, through high efficiency and charcoal filters, to the exhaust 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 basis accident, and signif-icant uncontrolled release would result. High radiation in the vicinity of t he bypass line would also make immediate c even if identified as the source of lea DUPLICATE DOCUMENT 1/ Current NRC requirements call for Entire document previously control hydrogen buildup. Palisad entered into system under: nuo 79. M, D95, /33 1351 290 uo. or geges: 9}}