ML19282C216

Submits Final Rept on Deficiency & Corrective Actions Re Heating & Ventilating Ductwork Hangers

ML19282C216
Person / Time
Site:	Sequoyah
Issue date:	01/29/1979
From:	Gilleland J TENNESSEE VALLEY AUTHORITY
To:	James O'Reilly NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION II)
References
NUDOCS 7903220236
Download: ML19282C216 (2)

Text

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.- TENNESSEE VALLEY AUTHORITY II4trs.1%

CHATTANOOGA, TENNESSEE 37401 500C Chestnut Street Tower II JA.!t E l NN Mr. James P. O'Reilly, Director Office of Inspection and ?.nforcement U.S. Nuclear Regulatory Commission Region II - Suite 3100 101 Marietta Street Atlanta, Georgia 30303

Dear Mr. O'Reilly:

Y SEQUOYAH NUCLEAR PLANT UNITS 1 AND 2 - HEATING AND VE.IILATING DUCTWORK HANGERS - NCR SWP-78-S FINAL REPORT U

The subject deficiency was initially reported to NRC-OIE Inspector M. Gouge on January 2, 1979. Enclosed is our final report.

If you have any questions concerning this matter, please get in touch with M. R. Wisenburg at,FTS 854-2581.

Very truly yours, J/ J. E. Gilleland Assistant Manager of Power Enclosure ec: Mr. John G. Davis, Acting Director (Euclosure)

Office of Inspection and Enforcement U.S. Nuclear Regulatory Commission Washington, DC 20555 7 9 03220 A3h 740dV9 or ricIAL COPY

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ENCLOSURE SEQUOYAH NUCLEAR PLANT UNITS 1 6 2 HEATING AND VENTILATING DUCTWORK HANGERS NCR SWP-78-S-3 FINAL REPORT Description of Deficiency A recent design review revealed that certain heating and ventilating ductwork in the auxiliary building was not designed with sufficient supporting hangers to provide seismic Category I integrity. This condition typically occurs at locations where the ductwork is cantilevered beyond existing hangers co mate with expansion joints at blowers or other equipment. A total of about 70 hangers must be added to provide the required integrity.

Safety Implications If the condition had not been discovered and were not corrected, failure of the ductwork duging a seismic event could have resulted in excessively high radioactivity levels in the auxiliary building, and in the release of such levels to the environment. Also, falling ductwork could have caused failures of other safety systems, constituting a hazard to the health and safety of the public.

Corrective Actions The design drawings are being revised to specify the numbers and locations of ductwork hangers required for seismic Category I integrity. The required additional hangers will be installed in the auxiliary building. This work will be completed before the initial unit 1 fuel loading. No similar nonconformance is applicable to Watts Bar or subsequent TVA nuclear power plants.

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