ML20118A804

Suppls Response to NRC Bulletin 92-001 Re Thermal-Lag Fire Barriers.On 920625 Roving Fire Watch Established. Applicable Test Documentation Will Be Reviewed.List of Barriers Encl

ML20118A804
Person / Time
Site:	Summer
Issue date:	09/15/1992
From:	Skolds J SOUTH CAROLINA ELECTRIC & GAS CO.
To:	Ebneter S NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION II)
References
IEB-92-001, IEB-92-1, NUDOCS 9209280171
Download: ML20118A804 (4)

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a South Carolina Electric & Gas Company John L. Sholds P O Don 88 Wee President Jenkinsvme. SC 29065 Nuclear Operations (803) 345-4040 SCE&G

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September 15, 1992 Mr. S. D. Ebneter Regional Administrator U. S. Nuclear Regulatory Commission Regio 1 II, Suite 2900 101 Marietts Street, NW Atlanta, GA ?0323

Subject:

VIRGIL C. SUMMER NUCLEAR STATION DOCKET NO. 50/395 OPERATING LICENSE N0. NPF-12 RESPONSE TO NRC BULLETIN 92-01, SUPPLFMENT 1 SPECIAL REPORT 92-005, SUPPLEMENT 1 (0NO 920050)

South Carolina Electric & Gas Company submits the attached supplement report pursuant to NRC Bulletin 92-01, Supplement 1, Failure of Thermo-Lao 330 Fire Barrier System to Perform its Specified Fire Endurance Function.

This report satisfies the requirements of Technical Specifications 6.9.2 identifying fire barriers which are inoperable for greater than seven days.

Should you have any questions, call at your convenience.

Very truly yours.,.

b l

John L. Skolds l

RJB:1cd t

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0. W. Dixon R. R. Mahan l

R. J. White l

General Managers G. F. Wunder L. D. Shealy NRC Resident inspector J. B. Knotts Jr.

Marsh & McLennan l

Document Control Desk INP0 Records Center NSRC RTS (ONO 920050)

)7I File (818.05) l v209280171 920915 l

PDR ADOCK 05000395 8

PDR N 0 0 ",5 NUCLEAR EXCELLENCE - A SUMMER TRADITION!

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Attachment to Mr. S. D. Ebneter Letter SPR 920005 Supplement 1 Rage 1 of 4 I

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SOUTH CAROLINA ELECTRIC & GAS COMPANY FIRE BARRIER RfPORT PER NRC BULLETIN 92-01, SUPPLEMENT _1 AND TECHNICAL SPECIFICATION 6.9.2

,l Thermo-Lag 330 barrier material is used in five locations at Virgil C. Summer i

Nuclear Station.

Each installation is_ designed to provide 1-hour fire barriers to meet the separation requirements of 10 CFR 50, Appendix R.

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l Thermo-Lag Panels are used to protect Cab'e Tray 3088. This cable tray is 18 inches wide and supplies various A-Train loads.

Table B j

(attached) identifies the affected loads.

Thermo-Lag preshaped conduit sections are used to protect a 3 inch conduit which supplies DC power to the Main Control Board.

Thermo-Lag Panels and a steel frame is used to enclose two conduits j

which contained Nuclear Instrument signal cables. This installation is identified by Thermal Science, Inc., as a Self Supported Structure, j

Due to its size and simila-ities in construction, this barrier may be susceptible to the same type of failures as the large cable trays, Thermo-Lag Panels and Flexi-Blanket are used to protect Unistrut and j

threaded rods which suspend a M-Board fire barrier over the "A" Service Water Booster Pump. This is an upgrade to a pre-existing fire barrier 4

previously reviewed by the NRC.

i Thermo-Lag preshaped conduit sections are used to protect 2 conduits which provide "A" Train power to the "C" chiller. This barrier is l

installed to maintain swing component capability.

Initially.

compensatory actions were established for this fire barrier. However, i

based on the definition "small diameter conduits" received from the NRC and NUMARC meeting of July 7, 1992, compensatory sctions were suspended for this area. Compensatory actions ~were re-initiated upon receipt of j_

Supplement 1 on August 31, 1992, i

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The location, type and purpose of all Thermo-Lag installations are identified i

on Table A (attached). Upon receipt of NRC Bulletin 92-01, a Non-Conformance Notice (NCN) and Removal Restoration Sheet-(R&R) were initiated to identify i

l the-condition of the Thermo-Lag fire barriers. A roving fire watch was established on June 25, 1992, to tour each room containing a Thermo-Lag fire bacrier.

Station procedures require an inspection of each room on an _ hourly basis, provided the fire detection capability exists..In the event of a_ loss of fire detection capability, a continuous-fire watch will be established in each area.

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Attachment to Mr. S. D. Ebneter Letter SPR 920005, Supplement 1 Dage R of 4 South Carolina Electric & Gas Company has established compensatory actions as required by NRC Bulletin 92-01, Supplement 1.

We will continue to work with Thermal Science, Inc., and the industry to develop a course of action to ensure the fire barriers are capable of performing their design function.

This course of action may include one or more of the following:

1.

Review available test documentation to reaffirm acceptability of existing fire barriers. This may require performance of site specific fire endurance tests.

2.

Receive and review adequate test documentation to upgrade the present installations.

3.

Replacement of Thermo-Lag fire barriers with a tested, approved fire barrier system.

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e Attachment to Mr. S. D. Ebneter Letter SPR 920005, Supplement 1 Page,3 of 4 TABLE:A THERMO-LAG FIRE BARRIERS FIRE NRC BARRIER BULLETIN 10#

TYPE SIZE LOCATION APPLICABILITY FUNCTION 24A-TW SSS*

8 X 13" CB 36-03 2

_ Separation of NI-31 ard i

NI-32 signal cables from NI-33 power cable.

58 74 Cable 18" IB 12-025 1, 2 Protection of Cable Tray I

Tray IB 36-02 3088, (see Table B for components supplied).

I 59-TW Conduit 4"

IB 26-01 2

Protection of "C" Chiller, A-Train power supply.

74-TW Conduit 3"

CB 12-04 1, 2 ProtectionofDCpowerto!

Main Control Board, i

76-TW Panels N/A IB 12-02S 2

Protection of supports l

i for M-Board fire barrier j

Flexi over "A" Service Water Blanket Booster Pump.

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i SSS*: Self Supported Structure made from prefabricated panels.

CB:

Control Building IB:

Intermediate Building 1:

NRC Bulletin 92-01 2:

NRC Bulletin 92-01, Supplement I i

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Attachment to Mr. S. D. Ebneter Letter

,. SPR 920005, Supplement 1 Page 4 of 4 TABLE B Components Supplied Through Cable Tray 3088:

Equipment Safety Number Name Class XFN0038A Battery & Charging Room Air Handling Unit "A" (NNS)

Supply Fan XFN0039A Battery Room Exhaust Fan "A" (NNS)

XES2001A Speed Switch, Component Cooling Pump "A" (SR)

XES2001C Speed Switch, Component Cooling Pump "C" (SR)

XPN7200A Control Room Evacuation Panel (SM XSW0001 Reactor Trip Switchgear (SR)

[

XCA0001A S.S. Power Cabinet lA

-(NNS)

XCX5201 Diesel Generator "A" Control Cubicle (SR)

XPN5504 Diesel Generator "B" Relay & Terreinal Panel (SR)_

XES0006-Diesel Generator "A" Starter DC Fuel Oil Pump (SR)

XEX4201 Diesel Generator "A" Exciter Regulator Cubicle (SR)

XPN5248 Relay & Isolation fuse Panel (SR) l XBCIA DC Distribution Bus lA Battery Charger (SR)

XBCIA-1B DC Distribution Bus lA-1B Backup Battery Charger (SR) l XPh6_59 Isolation Fuse Panel (SR)

XSWIDA 7.2 KV Switchgear, Bus 1DA (SR) l XSWlDA1 ESF 480 Volt Unit Substation, Bus 10A1 (SR) 4 XL MA2 ESF 480 Volt Unit Substation, Bus 1DA2 (SR) l 2011 Reactor Protection Under Frequency & Under Voltage (SR) l Panel 1

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XPN7106 Main Control Board Termination Cabinet (SR) i l

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