ML20099J069
| ML20099J069 | |
| Person / Time | |
|---|---|
| Site: | Bellefonte  |
| Issue date: | 02/27/1985 |
| From: | Hufham J TENNESSEE VALLEY AUTHORITY |
| To: | Grace J NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION II) |
| References | |
| NUDOCS 8503190584 | |
| Download: ML20099J069 (2) | |
Text
I I
TENNESSEE VALLEY AUTHORITY CH ATTANOOGA, TENNESSEE 374ol 400 Chestnut Street Tower II B5 gm g February 27, 1985 g7*, N BLRD-50-43 8/84-42 BLRD-50-439/84-38 U.S. Nuclear Regulatory Commission Region II Attn:
Dr. J. Nelson Grace, Regioral Administrator 101 Marietta Street, NW, Suite 2900 Atlanta, Georgia 30323
Dear Dr. Grace:
BELLEFQiTE NUCLEAR PLANT UNITS 1 AND 2 - CONTROL ROOM PRESSURIZATION BOUNDARY LOSS THROUGH DRAIN AND VENT LINES - BLRD-50-438/84-42, BLRD-50-439/84 SECOND INTERIM REPORT The subject deficitricy was initially reported to NRC-0IE Inspector P. E. Fredrickson on June 25, 1984 in accordance with 10 CPR 50.55(e) as NCR BLN BLP 8407 Our first interim report was sutxnitted July 25, 1984.
Enclo. sed is our second interim report. We expect to sutrait our next report on or about Mardi 5,1986.
If you have any questions, please get in touch with R. H. Shell at FTS 858-2688.
Very truly yours, TENNESSEE VALLEY AUTHORITY J. W. Hufham, Manager Licensing and Regulations Enclosure cc:
Mr. James Taylor, Director (Enclosure)
Office of Inspection and Enforcement U.S. Nuclear Regulatory Commission Washington, D.C.
20555 Records Center (Enclosure)
Institute of Nuclear Power Operations 1100 Circle 75 Parkway, Suite 1500 Atlanta, Georgia 30339 8503190594 850227 g6 goa ^oocaosoome 4
wey An Equal Opportunity Employer
r 4
/
ENCLOSURE
' BELLEFCNTE NUCLEAR PLANT UNITS 1 AND 2 CONTROL ROOM PRESSURIZATION BOUNDARY LTS THROUGH DRAIN AND VENT LINES BLRD-50-438/84-42, BLRD-50-439/84-38 NCR BLN BLP 8407 10 TR 50.55(e)
SECOND INTERIM REPORT Description of Deficiency During a design review initiated to investigate the generic concerns of Watts Bar nonconformance report (NCR) WBN WBP 8335 (WBRD-50-390/83-70, 50-391/83-65),
TVA determined that a similar condition exists at Bellefonte (BLN). Floor, equipnent and sanitary facility vent and drain lines which penetrate the floor and roof slabs of the main control room (MCR) and technical support center (TSC) are not adequately designed to prevent air leakage into the MCR habitability system pressurization boundary. There is no assurance that traps will maintain enough water to seal off leak paths into the habitability zone ror, in most cases, are pipes sufficiently supported to maintain their pressure boundary in the case of a seismic event.
Interim Progress TVA is in the process of changing plant design so that drain, vent, and potable water piping for the sanitary facilities that penetrate the pressurization boundary shall be manually isolated if a failure occurs during a seismic event.
A segment of piping at each penetration shall be seismically supported and provided with a manual isolation valve. Floor drainage piping that penetrates the pressurization boundary shall be seismically supported to maintain the pressure boundary and shall be provided with loop seals.
9