ML20214R476

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Documents Deviations Noted at Facility Re Existence of RTV Foam Seals Not Conforming to Requirements,Per 870515 Telcon W/Region Iv.Preliminary Evaluations on Acceptable Methods of Repair Will Be Completed by 870522
ML20214R476
Person / Time
Site: Wolf Creek Wolf Creek Nuclear Operating Corporation icon.png
Issue date: 05/18/1987
From: Brown R
B&B PROGRESSIVE MATERIALS & TECHNOLOGIES, INC. (PROMA
To: Martin R
NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION IV)
References
NUDOCS 8706080161
Download: ML20214R476 (4)


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PROGRESSIVE MATERIALS AND TECHNOLOGILS,INC.

,gg Q.100.87.72 May 18, 1987 Mr. Robert Martin United States Nuclear Regulatory Commission 611 Ryan Plaza Drive Suite 1000 Arlington, Texas 76011

Reference:

Notification of deviations at Wolf Creek Generating Station Gentlemen:

Pursuant to discussions with Mr. James Gagliardo of USNRC Region IV on Friday, May 15,1987 at 10:45 a.m. thin report constitutes written notification of the existence of silicone RTV foam seals at the Wolf Creek Generating Station that do not conform to minimum requirements. This report in a culmination of information collected by both Wolf Creek Nuclear Operating Corporation and B & B PROMATEC, Inc.

On Friday, May 8, 1987 at approximately 4:30 p.m. PROMATEC was contacted by representatives of the Wolf Creek Generating Station and advised that a cample inspection of allicone RTV foam nealo revealed several discrepancies which were raining concerns that a generic problem may exist with silicone RTV foam seals. The cample inspection consisted of forty (40) seals of which twenty-one (21) were determined as not meeting minimum requirements for reasono such an voida, ohrinkage and lack of fill. PROMATEC concurred that the discrepancy rate was cause for concern and dispatched a representative to Wolf Creek with the objective of determining the nature and extent of the problem.

On Monday, May 11, 1987 the PROMATEC repreacntative began an independent re-inspection of the twenty-one rejected seals in an effort to gain firsthand knowledge of the extent of the problem. Although the reinspection indicated that the actual number of rejectable ceals wan fourteen (14), PROMATEC and Wolf Creek representatives continued to be in agreement that the discrepancy rate wan cause for concern.

On Wednesday, May 13, 1987 the writer met with Wolf Creek representativen to evaluate the information collected to date and to determine the proper courne of action. Daaed on the fact that the typen of ceal discrepancies identified would allow at least limited operability and adequate fire watch personnel were posted, it was determined that the nafe operation of the plant was not compromined; however, it was agreed that due to the ponnibly generic nature of 8706000161 070510 '

PDR ADOCK 05000402 P pon y g .q W P.O. BOX 4672

  • HOUSTON, TEXAS 77210 * (713) 690 5240 E riuo

I i To: Mr. Robert Martin Q.100.87.72 From: Mr. R.W. Brown Page 2 of 2 the problem and the lack of conclusive evidence concerning the potential for a substantial safety hazard, the condition would be reported to the Nuclear Regulatory Commission for assistance in determining appropriate disposition.

The number and location of discrepant seals is presently limited to the four-teen (14) previously identified in this report; however, the reject rate of the first sampling taken indicates a need to perform additional inspections to either rule out or substantiate a generic problem with RTV foam seals. The existence of similar problems at other facilities is indeterminate at this time; however, considering the industry wide use of silicone RTV foam as a fire sealant, the potential exists for such conditions elsewhere.

PROMATEC and Wolf Creek Nuclear Operating Corporation are presently evaluating various methods for correcting each discrepant seal, including any identified during the reinspection process. Until such time that the cause of shrinkage and voids in some seals is determined, we have recommended that silicone RTV foam not be used as a repair material at Wolf Creek. Alternate methods of repair under consideration include the following:

1) fire rated adhesive sealant for voids and shrinkage. An evaluation is currently in progress to determine the design limitations of this method based on an extrapolation of fire tests previously conducted which qualified certain types of adhesive sealant as a primary seal.
2) PROMATEC LDSE or TS-MS-0045B for seals with inadequate fill. In cases where sufficient depth in the penetration exists these products may be installed against the existing foam seal without necessitating removal. We are also in the process of evaluating both products as a potential repair material for voids and shrinkage that exceed limita-tions established for adhesive sealant.
3) PROMATEC Promarlex in cases where existing seals must be removed or when design movement of penetrating items preclude the use of rigid seals such as LDSE or TS-MS-00450.

Due to the indeterminate scope of this problem, we are unable to provide an accurate schedule for completion of corrective actions at this time. Prelim-Inary evaluations on acceptable methods of repair will be completed by Friday, May 22, 1987. Additionni information will be provided as it becomes avail-able.

Sincerely yours, PROMAIEC

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a h A M.41 H.W. Brown Quality Assurance Manager RWB/dje lHRMEGTIDTC

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..- PROGRESSIVE MATERIALS AND TECHNOLCKAES,INC.

1 Q.100.87.72 May 18, 1987 Mr. Robert Martin United States Nuclear Regulatory Commission 611 Ryan Plaza Drive Sulte 1000 Arlington, Texas 76011

Reference:

Notification of deviations at Wolf Creek Generating Station Gentlemen:

Pursuant to discussions with Mr. James Gagliardo of USNRC Region IV on Friday, May 15, 1987 at 10:45 a.m. this report constitutes written notification of the existence of silicone RTV foam ceals at the Wolf Creek Generating Station that do not conform to minimum requirements. This report is a culmination of information collected by both Wolf Creek Nuclear Operating Corporation and B & B PROMATEC, Inc.

On Friday, May 8, 1987 at approximately 4:30 p.m. PROMATEC was contacted by representat ives of the Wolf Creek Generating Station and adviced that a sample inspection of allicone RIV foam seals revealed several discrepancies which were raising concerns that a generic problem may exist with silicone RTV foam seals. The sample inspection consisted of forty (40) seals of which twenty-one (21) were determined as not meeting minimum requirements for reasons such as voids, shrinkage and lack of fill. PROMAlfC concurred that the discrepancy rate was cause for concern and dispatched a representative to Wolf Creek with the objective of determining the nature and extent of the problem.

On Monday, May 11, 1987 the PROMATEC representative began an independent re-inspection of the twent; anc rejected seals in an effort to gain firsthand knowledge of the extent of the problem. Although the reinspection indicated that the actual number of rejectable seals was fourteen (14), PROMATEC and Wolf Creek representat ives continued to be in agreement that the discrepancy rate was cause for concern.

On Wednesday, May 13, 1987 the writer met with Wolf Creek representatives to evaluate the information collected to date and to determine the proper course of action. Based on the fact that the types of seal discrepancies identified would allow at least limited operability and adequate fire watch personnel were posted, it was determined thnt the safe operation of the plant was not compromised; however, it was agreed that due to the possibly generic nature of M

11u s t P.O. BOX 4672

  • HOU$ TON, TEXA5 77210 e (713) 690 5240 N

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To: Mr. Robert Martin Q.100.87.72 from: Mr. R.W. Brown j Page 2 of 2 the problem and the lack of conclusive evidence concerning the potential for a substantial safety hazard, the condition would be reported to the Nuclear 4

i Regulatory Commission for assistance in determining appropriate disposition.

l The number and location of discrepant seals is presently limited to the four-1 teen (14) previously identified in this report; however, the reject rate of j the first sampling taken indicates a need to perform additional inspections to p j either rule out or substantiate a generic problem with RTV foam seals. The existence of similar problems at other facilities is indeterminate at this

time; however, considering the industry wide use of silicone RTV foam as a j fire sealant, the potential exists for such conditions elsewhere.

i i PROMATEC and Wolf Creek Nuclear Operating Corporation are presently evaluating various methods for correcting each discrepant seal, including any identified l during the reinspection process. Until such time that the cause of shrinkage

! and voids in some seals is determined, we have recommended that silicone RTV 3

foam not be used as a repair material at Wolf Creek. Alternate methods of

  • j repair under consideration include the following:

" r

1) fire rated adhesive sealant for voids and shrinkage. An evaluation is 4

currently in progress to determine the design limitations of this j method based on on extrapolation of fire tests previously conducted which qualifted certain types of adhesive sealant as a primary seal. l

) 2) PROMATEC LDSE or TS-MS-00459 for seals with inadequate fill. In cases

where sufficient depth in the penetration exists these products may i be incialled against the existing foam seal without necessitating ,

removal. We are also in the process of evaluating both products as a  !

I potential repair material for volds and shrinkage that exceed limito-l tions established for adhesive sealant.

3) PROMATEC Promarlex in cases where existing seals must be removed or when design movement of penetrating items preclude the use of rigid

! seals such as LDSE or TS-MS-00450.

l j Due to the indeterminate scope of this problem, we ate unable to provide an j accurate schedule for completion of corrective actions at this time. Prelim-j inary evaluations on acceptable methods of repair will be completed by friday, j May 22, 1987. Additional information will be provided as it becomes avull-j able. i i

i a

Sincerely yours, PROMATEC l

./M.+1

l. H.W. Brown j,

Quality Annurance Manager j RWB/dje i,

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