ML20092M158
| ML20092M158 | |
| Person / Time | |
|---|---|
| Site: | Bellefonte  |
| Issue date: | 06/22/1984 |
| From: | Mills L TENNESSEE VALLEY AUTHORITY |
| To: | James O'Reilly NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION II) |
| References | |
| NCR-2927, NUDOCS 8407020149 | |
| Download: ML20092M158 (2) | |
Text
"o'.
TENNESSEE VALLEY AUTHORITY CHATTANOOGA TENNESSEE 37401 400 Chestnut Street Tower II g jQ{N June 22, 1984 BLRD-50-438/84-26 BLRD-50-439/84-25 U.S. Nuclear Regulatory Commission Region II Attn:
Mr. James P. O'Reilly, Regional Administrator 101 Marietta Street, NW, Suite 2900 Atlanta, Georgia 30323
Dear Mr. O'Reilly:
BELLEFONTE NUCLEAR PLANTS UNITS 1 AND 2 - SHRINKAGE / SPLITS IN DOW CORNDiG FOAM PENEIRATION SEALS BLRD-50-438/84-26, BLRD-50-439/84 FINAL REPORT
' The ~ subjoot deficiency was initially reported to NRC-0IE Inspector P. E. Fredrickscn on March 19, 1984 in accordance with 10 CFR 50.55(e) as
-NCR 2927 This was followed by our interim report dated April 17, 1984.
Enclosed is our final report.
If you have any questions,.please get in touch with R. H. Shell at FTS 858-2688.
Very truly yours, TENNESSEE VALLEY AUTHORITY L..M. Mills, nager-Nuclear Licensing Enclosure co:
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 Circle 75 Parkw y, Suite 1500 Atlanta, Georgia 30339 f
8407020149 840622 PDR ADOCK 05000438 S
PDR p% 6Y 1983-TVA 50m ANNIVERSARY g
g An Equal Opportunity Employer
4 g
ENCLOSURE c
~
j s
BELLEFONTE NUCLEAR PLANTS P irs 1 AND 2 SHRINKAGE / SPLITS IN DOW CORNING NAM PENETRATION SEALS BLRD-50-438/84-26, BLRD-50-439/84-25 NCR 2927 10 CFR 50.55(e)
FINAL REPORT Description of Deficiency Bus penetrations located in Diesel Generator Building Units 1 and 2 were reinspected due to the fact that after an extended period of time, shrinkage These penetrations and splits have occurred in the larger penetration seals.
were reinspected to assure room temperature vulcanizing (RTV) foam firestops were still in compliance with Bellefonte Quality Control Procedure (BNP-QCP) 5.18, "Firestops, Waterstops, and Pressure Seals." There are eight bus A total of seven penetrations were reinspected in penetrations in each unit.
both units and two penetrations in unit 1 and two in unit 2 had excessive Subsequent Ninspection of the remaining nine splits and shrinkage.
seals in the DG buildings myealed splits in three seals and shrinkage in six seals. Nonconformance report (NCR) 2927 has been revised to include the results of all 16 bus penetration seal inspections.
In addition to minspection in the DG buildings, four RTV foam seals were reinspected in the Auxiliary Building. Two of the seals had excessive shrinkage.
Dow Corning informed TVA that the splits are due to shrinkage which The volume of the foam normally occurs during the curing process.
will typically decrease 1 percent for each 180F decrease in ambient temperature.
Safety Implications The subject foam seals perform a secondary safety function in that they are intended to impede the spread of a fire which could If this condition had remained jeopardize safety-related components.
uncorrected, it could have adversely affected the safety of operations of the plant.
Corrective Action Dow Corning has advised TVA that the seals may be repaired by adding more foam to the seal. Therefore, TVA will repair the penetrations in accordance with the rmnufacturer's instructions and BNP-QCP 5.18.
BNP-QCP 518 is being revised to mquire periodic seal inspections until it can be confirmed that temperature changes will not affect them.
All corrective actions will be complete by January 11, 1985
,.7 nf 0tg;;Y t
1 i
4
~
L Th,,
t j'no
~
. x,.
w n ':
3 L,n c. s Q
N 6:
y,n y.
a