ML20009H577

Ro:On 810608,fire Barrier Penetration Fire Seals Found in Nonconformance W/Approved Configuration Requirements. Deficiencies Occurred During Mod 445-N Implementation.Seals Will Be Repaired During Refueling Outage

ML20009H577
Person / Time
Site:	Robinson
Issue date:	07/22/1981
From:	Starkey R CAROLINA POWER & LIGHT CO.
To:	James O'Reilly NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION II)
References
RSEP-81-1151, NUDOCS 8108100263
Download: ML20009H577 (3)

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W ,id (no n4wnelQ 1ra:.m.ac;.w u -ny.m H. B. ROBINSON STEAM ELECTRIC PLANT Post Office Box 790 Hartsville, South Carolina 29550 JUL 2 % 13iH Rooinson File No: 2-0-4-a-9 Serial:RSEP/81-1151 ff b ./,%

Mr. James P. O'Reilly, Director Q h U. S. Nuclear Regulatory Commission j ,

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]3 Region II, Suite 3100 -

101 Marietta Street T p Q$ Ng, i Atlanta, Georgia 30303 6, g*g# 3 H. B. ROBINSON STEAM ELECTRIC PLANT, UNIT NO. 2 4 '

g, s DOCKET NO. 50-261 @

LICENSE NO. DPR-23 N @

THIRTY DAY SPECIAL REPORT - FIRE BARRIER PENETRATION FIRE SEALS

Dear Mr. O'Reilly:

Carolina Power and Light Company (CP&L) submits the following thirty day special report as required by Technical Specifications (TS) 3.14.7.2.c.

This specification requires that a special report be prepared if an in-l operable fire barrier penetration seal is not restored to an operable l condition within seven days. As of June 18, 1981, H. B. Robinson Unit l No. 2 (HBR2) has had five fire barrier penetration seals in a degraded state, and therefore inoperable, for more than seven days. The required backup fire detectors have been verified operable which satisfies the compensatory action required by TS 3.14.7.2. The following is a descrip-tion of the status of these five penetration seals. ,

Background

On May 15, 1981, NRC issued Amendment No. 57 to License No. DPR-23. This amendment updated the fire protection Technical Specifications to include operability and testing requirements for new fire protection systems and p included a 7 day inoperability requirement for fire barrier penetration ,

seals which was not in the previous Technical Specifications. At this time HBR2 was shutdown for a steam generator inspection outag,e.

On June 11, 1981, the unit went critical, and the seven day inoperability period described in TS 3.14.7.2 for the above seals began. On June 18, 1981, CP&L was required to submit this report pursuant to TS 6.9.3.g within the next 30 days. This report is being submitted beyond this 30 day period due to an administrative delay. This delay was discussed with Mr. C. Julian of Region II on July 20, 1981.

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, g . 4-Letter to Mr. James P. O'Reilly Serial:RSEP/81-ll51 Page 2 Event During a Control Room habitability inspection on June 8, 1981, while the plant was shutdown, five of eighteen fire barrier penetration seals in the Control Room floor were identified as not satisfying the approved configuration requirements of Maintenance Instruction 12, " Repair of Cable Penetrations". Specifically two problems were noted: 1) In two penetrations, FP-30 and FP-31, the open ends of conduits penetrating the seals were filled with Kao-wool mineral wool fiber material instead of the required BISCO Silicon RTV foam, and 2) In three cable tray penetra-tions, FP-33, 37 and 38, only one h-inch Marinite-I board was bolted to the bottom of these floor penetrations as a backing to the Kao-wool seal instead of the required two -inch Marinite-I boards. These deficiencies apparently occurred during Modification 445-N implementation and were not identified during the post modification inspections.

The small open end conduit penetrations through cable tray penetration seals are unique to the Control Room. Modification 445-N did not ad-dress filling these conduits with BISCO Silicon RTV foam because the modification did not treat these conduit penetratiocs within the cable tray penetrations separately from the cable tray penetrations themselves.

Following the completion of Modification 445-N, CP&L initiated an inspec-tion of conduit penetrations throughout the plant for review of the proper sealing configuration. The two Control Room conduit penetrations in question were inadvertently omitted from this list as they were considered pert of the cable tray penetrations. All conduit penetration seals other than the two omitted from the list did meet the configuration requirements of MI-12.

The small clearances between the cable trays and the Control Room cable tray penetrations prevented the installation of the additional h-inch Marinite-I boards to FP-33, 37 and 38. A preliminary review *of plant cabJe trays indicates that this situation does not exist elsewhere in the plant.

Because the five fire barrier penetration seals are located in Control Room cabinets it would be difficult to effect repairs without possibly compromising the control circuits for safe shutdown equipment. As a result, the earliest possible date for repaire is during the next scheduled refueling outage in late 1981. Operation in the interium with the five fire barrier penetration seals inoperable will not constitute a safety hazard far the following reasons:

1. The seals in their current configuration are nearly degraded and do provide a fire barrier.

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Letter to Mr. James P. O'Reilly Serial:RSEP/81-1151 Page 3

2. Penetration Seals FP-30 and FP-31 are small conduits between the Control Room and the old Unit No. 1 Cable Spread Room.

Fire detection in both rooms is operable and should provide early warning of fires in these zenes.

3. Penetration Seals FP-33, FP-37 and FP-38 are located between

- the Unit No. 2 Cable Spread Room and the NIS cabinets and RTGB in the Control Room. Fire detection in these areas is operable and should provide early warning of a fire. In addition, the Cable Spread Room contains a HALON 1301 Suppres-sion System. All cables in the Cable Spread Room are coated with Intumastic 285 flame retardant material which would pre-vent the spread of any fire along cables in this zone. Thase factors, combined with the fact that there are almost no fixed or transient combustibles in the Cable Spread Room make it highly unlikely that a fire could occur of sufficient magnitude to reach the existing seals and create a significant hazard to safe shutdown capabilities.

HBR2 will repair the five fire barrier penetration sealc during the next y refueling outage, and will thereby be in full compliance with TS 3.14.7.2 1

before achieving criticality at the end of the 1981 refueling outage.

If you have any questions, please contact me or my staff.

. Very truly yours, R.-B. Starkey, Jr.

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, General Manager l

H.B.RobinsonS.E.P1put

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