ML20077B861
| ML20077B861 | |
| Person / Time | |
|---|---|
| Site: | Bellefonte  |
| Issue date: | 07/14/1983 |
| From: | Mills L TENNESSEE VALLEY AUTHORITY |
| To: | James O'Reilly NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION II) |
| References | |
| REF-PT21-83 10CFR-050.55E, 10CFR-50.55E, NUDOCS 8307250464 | |
| Download: ML20077B861 (2) | |
Text
l So-4 9 939 UsT;F.JgNESSEE; VALLEY AUTHORITY
/It biA3TA36@. TENNESSEE 374ol 400 Chestnut Street Tower II B MD : 28 July 14, 1983 U.S. Nuclear Regulatory Commission Region II 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 - FAILURE OF MAIN STEAM LINES BECAUSE OF MAIN FEEDWATER OVERFILL - NCR BLN NEB 8004 - TENTH INTERIM REPORT On March 19, 1980, Bruce Cochran, NRC-0IE Region II, was informed that the subject nonconformance was determined to be reportable in accordance with 10 CFR 50 55(e). This was followed by our interim reports dated April 17, September 23, and December 29, 1980; June 25 and December 28, 1981; March 31, August 27, and November 18, 1982; and March 24, 1983 Enclosed is our tenth interim report. We expect to submit our next report by November 21, 1983 We consider 10 CFR Part 21 to be applicable to this nonconformance.
If you have any questions concerning this matter, please get in touch with R. H. Shell at FTS 858-2688.
Very truly yours, TENNESSEE VALLEY AUTHORITY L. M. Mills, Fanager Nuclear Licensing Enclosure l
cc (Enclosure):
Mr. Richard C. DeYoung, Director Office of Inspection and Enforcement U.S. Nuclear Regulatory Commission Washington, D.C.
20555 Mr. James McFarland Senior Project Manager Babcock & Wilcox Company P.O. Box 1260 Lynchburg, Virginia 24505 0FRC!AL COPY 8307250464 830714 PDR ADOCK 05000438 l
S PDR 1983-TVA SOTH ANNIVERSARY An Equal Opportunity Employer
ENCLOSURE BELLEFONTE NUCLEAR PLANT INITS 1 AND 2 FAILURE OF MAIN STEAM LINES BECAUSE OF MAIN FEEDWATER OVERFILL NCR BLN NEB.8004 10 CFR 50.55(e)
TENTH INTERTM _ REPORT
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Description of Deficiency f[
A preliminary safety concern, PSC 35-76, was fnitiated within BiW, Lynchburg, Virginia, which presents /the concern that.a potential exists for overfilling steam generators by excessive addition of main resdwater (MFW) or auxiliary feedwater (AFW).
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Excessive feedwater addition, as used here, is defined as a condition which would exist if feedwater (main or auxiliary) is continually added to the steam generators in an unplanned fashion at a rate greater than the core heat generation capability for converting it to steam. Overfill, the condition addressed in.this preliminary safety concern, may be defined as a limiting case of excessive feedwater addition which allows liquid spillage into the steam lines.
It is estimated that the time to overfill the integraf economizer once-through steam generators (IE0TSG) provided on the Bellefonte. Nuclear Plant is approximately 2 to 4 minutes with MFW and between 7 to 15 minutes with AFW.
Potential results of overfill could be:
1.
Steam line-deformation and failure because of water accumulat' ion.-
Steamgeneratorblowdownbecauseof$teamlinefailurewiththe 2.
potential for core return to power from a safe shutdown condition, excessive steam generator tube stress, exceeding reactor vessel NDT limits, or containment overpressurization.
Interim Progress Although the preliminary. analysis shows that the main steam line piping can withstand the MPW overfill event, TVA has not completed the final ar.alysis and verification. This analysis is expected to be completed soon and mere informntion will be forwarded in our final report.
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