ML20091M295
| ML20091M295 | |
| Person / Time | |
|---|---|
| Site: | Bellefonte  |
| Issue date: | 05/31/1984 |
| From: | Mills L TENNESSEE VALLEY AUTHORITY |
| To: | James O'Reilly NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION II) |
| References | |
| NUDOCS 8406110218 | |
| Download: ML20091M295 (2) | |
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-T TENNESSEE VALLEY AUTHORITY E 37401 i
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d /g. 8 May 31, 1984 BLRD-50-438/81-07
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BLRD-50-439/81-07 U.S. Nuclear Regulatory Commission 4
Region II l
Attn:
Mr. James P. O'Reilly, Regional. Administrator 101 Marietta Street, NW, Suite 2900 Atlanta, Georgia 30303
Dear Mr. O'Reilly:
BELLEFONTE NUCLEAR PLANT UNITS 1 AND 2 - CORROSION OF CARBON STEEL PIPING -
BLRD-50-438/81-07, BLRD-50-439/81 TENTH INTERIM REPORT The subject nonconformance was initially-reported to NRC-0IE Inspector F. S. Cantrell on December 30, 1980, in accordance with 10 CFR 50.55(e) as NCR BLN NEB 8010. This was followed by our interim reports dated January 29, May 22, September 23, November 12, and December 21, 1981,
' March 2 and August 11, 1982 and January 5 and October 20,_1983 Enclosed is our tenth interim report. This nonconformance has also been reported I~
for Sequoyah and Watts Bar Nuclear Plants. We expect to submit our next i
report by July 18, 1984.
If you ~have any questions concerning this matter, please get in touch with
-R. H. Shell at FTS 858-2688.
i Very truly yours, TENNESSEE VALLEY AUTHORITY L. M. Mills, Nanager Nuclear Licensing Enclosure cc:
Mr. Richard C. DeYoung, 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 Ciro]e 75 Parkway, Suite 1500 Atlanta, Georgia 30339 8406110218 840531 gDRADOCK-05000g g ggigLC d-9 O.
1983-TVA SOTH ANNIVERSARY 8M An Equal Opportunity Employer II
ENCLOSURE
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BELLEFONTE NUCLEAR PLANT UNITS 1 AND 2 CORROSION OF CARBON STEEL PIPING
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NCR BLN NEL 8010 BLRD-50-438/81-07, BLRD-50-439/81-07 10 CFR 50.55(e)
TENTH INTERIM REPORT Description of Condition It has been found that the original criteria for the use of carbon steel piping in raw water systems at TVA nuclear plants may not be adequate. Corrosion has been found to cause greater than predicted pressure drops when pipes are sized according to standard industry practice. In addition, the corrosion can cause a thinning of the pipe wall which may be in excess of the minimum wall thickness considered in the design of the systems. This condition could affect all raw water systems with carbon steel piping, such as the Essential Raw Cooling Water (ERCW) System, High Pressure Fire Protection System, and the pump room and oil coolers for the centrifugal charging pumps, the safety injection pumps, and the containment spray pumps. Also, most electrical board and room air-conditioning units use carbon steel piping. The High Pressure Fire Protection System is being handled separately under nonconformance report BLN MEB 8206 (BLRD 438/82-65, BLRD-50-439/82-58).
The problem of corrosion has been the subject of considerable study at TVA. A brief history of TVA's investigation of this matter was included in our first interim report.
Interim Progress TVA has issued physical drawings and insulation and mode analysis drawings per engineering change notice (ECN) 1457. A review is now being conducted, per ECN 1457, of the rigorous piping analysis data involving the modified ERCW system piping.
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