ML20101J723

Forwards follow-up to 951006 RAI Re GL 92-08, Thermo-Lag 330-1 Fire Barriers

ML20101J723
Person / Time
Site:	Summer
Issue date:	03/29/1996
From:	Gabe Taylor SOUTH CAROLINA ELECTRIC & GAS CO.
To:	NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM)
Shared Package
ML20101J726	List: ML20101J723 ML20101J753 ML20101J775
References
GL-92-08, GL-92-8, TAC-M85610, NUDOCS 9604020118
Download: ML20101J723 (4)

Text

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South Ctrolina Ehetric & Gis Comptny GIry J.TIylor '

l P.O. Box 88 Vice President l Jenkinsville SC 29065 Nuclear Operations

. (803) 345-4344

! SCFJrG seconcm March 29,1996 Document Control Desk U. S. Nuclear Regulatory Commission Washington, DC 20555

Gentlemen

Subject:

VIRGIL C. SUMMER NUCLEAR STATION l DOCKET NO. 50/395 .

OPERATING LICENSE NO. NPF-12 FOLLOW-UP TO THE REQUEST FOR ADDITIONAL INFORMATION l

' REGARDING GENERIC LETTER 92-08 ISSUED PURSUANTTO 10 CFR 50.54(f)

ON OCTOBER 6,1995 - VIRGIL C. SUMMER NUCLEAR STATION, UNIT NO.1 (TAC NO. M85610)

South Carolina Electric & Gas Company submits the attached pursuant to the subject NRC request.,

I declare that the statements and matters set forth herein are true and correct to the  !

oest of my knowledge,information, and belief. l Should you have any questions, please cail Ms. Linda Ma'rtin at (803) 345-4217 at your convenience.

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Very truly yours, ,

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d3org eA i UM/GJT/nkk Attachment / Enclosures c: J. L. Skolds W.

R. R.F.Mahan Conway(w/o attachment) ,

R. J. White '

S. D. Ebneter J. I. Zimmerman '

NRC Resident inspector J. B. Knotts Jr.

NSRC

DMS (RC-96-0090)

J RTS (GL 920008)

File (815.14) g40jj@ $$$

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l NUCLEAR EXCELLENCE- A SUMMER TRADITIONI iy)a' ti ,

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Docom:nt Control Desk GL 92-08 Attachment i Page 1 of 3 SOUTH CAROLINA ELECTRIC & GAS COMPANY l VIRGIL C. SUMMER NUCLEAR STATION l

FOLLOW UP TO THE REQUEST FOR l ADDITIONAL INFORMATION REGARDING GENERIC LETTER 92-08 "THERMO-LAG 330-1 FIRE BARRIERS" 1.0 REQUEST FOR ADDITIONAL INFORMATION (RAl) OF OCTOBER 6.1995 This response addresses the ampacity issues and questions identified in the NRC letter of October 6, 1995. As the NRC has previously stated, cable ampacity concerns are considered a long term cable qualification issue and not an immediate operability issue. It has been SCE&G's position to follow the industry solution on this issue. We evaluated the potential impact of ampacity derating in 1994 and responded in February 11,1994 pending additionalinformation from NEl. Since that time, no additional information on ampacity derating has been issued by NEl. SCE&G has concluded that the Thermo-Lag 330-1 electrical barriers installed at the facility for Appendix R related circuits will be eliminated through replacement with an alternative means of protection described below.

• Cable Tray 3088 & Conduit XX-7177A  ;

Remove the Thermo-Lag 330-1 fire barrier on Cable Tray 3088 and Conduit XX-7177A. The Appendx R required circuits within the protected portions of this raceway will be replaced with 1-hour fire rated cable. An exemption will be processed, in accordance with the attached schedule, to address the use of fire rated cable for both Cable Tray 3088 and Conduit XX-7177A.

• NI Boxed Enclosure This Thermo-Lag 330-1 barrier was identified in the March 23,1995 response to be a candidate  ;

for exemption. SCE&G will process an exemption,in accordance with the attached schedule, for this barrier which will demonstrate that the Appendix R function for the Ni circuits can be adequately performed through alternative means. Ampacity concerns do not apply to this enclosure since it contains only instrumentation circuits.

• Conduits VUL21A I This Thermo-Lag 330-1 barrier was identified in the March 23,1995 response to be outside the scope of Generic Letter 92-08.

• SWBP Heat Shield This non-rated Thermo-Lag 330-1 application was identified in SCE&G's March 23,1995 and previous responses to be outside the scope of Generic Letter 92-08. The Thermo-Lag 330-1 material provides protection for the unistrut supports; the heat shield function is maintained by the shield's M-Board panels. A detailed engineering review of this heat shield is retained on site for l NRC staff review.  !

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DocQm:nt Control Desk GL 92-08 l Attachment I Page 2 of 3 2.0 Response to Section 1.0 and 2.0 of the RAI This NRC RAI requests SCE&G to submit its ampacity derating evaluations, including any applicable test reports, in order to provide an adequate response to Generic Letter 92-08 reporting requirement 2(c). Enclosed are copies of the original calculations used to envelope ampacity issues related to the installation of Thermo-Lag on cable tray 3088 and conduit XX-7177A.

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• DC08490-004 Cable Tray 3088

• DC08490-008 Conduit XX-7177A l

In the NRC RAI, the staff indicated that SCE&G's March 23,1995 response to ampacity derating issues on conduit XX-7177A was "non-responsive". Apparently, the NRC concluded that l SCE&G's statement in Section 1.3.3, independent Testing, of the March 23,1995 response, "without conclusive determination" meant SCE&G would not address the ampacity concerns for this conduit. Actually, had SCE&G opted to retain / modify the barrier on conduit XX-7177A, we l intended to perform an evaluation (s) of the installation to demonstrate the barrier is bounded by l existing ampacity test data without performing site specific (conclusive) tests. SCE&G l- considered it premature to perform detailed evaluations, tests, or analyses for ampacity derating 1 l

untilit was determined that retention of the Thermo-Lag 330-1 fire barriers was necessary. As i indicated in Section 1.0 of this response, the Thermo-Lag Barriers at VCSNS will be removed with exception of the Thermo-Lag support protection for the M-Board SW Booster Pump Heat Shield.

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GL 92-08 i Attachment l Page 3 of 3 3.0 Revised Resolution Schedule 3.1 Basis for Schedule Revision 1

The schedule provided in Section 2.2 has been revised by an additional 3 months since  ;

portions of the work will be performed during the Fall 1997 Refueling Outage (Ri -10).

l 3.2 Revised Schedule l SCE&G's revised follow-up schedule for resolution of Generic Letter 92-08 is shown below:

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1. Receive the final NEl August 24,1994 Complete Application Guide.

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2. Complete reviews, analyses, Month 18 - February 24,1996 Complete and examinations to establish bounded parameters and conceptual design.

3. Complete Design and Submit Month 24 - August M,1990 in Process ,

Exemption Requests. '

4. Complete Installation for Work Month 36 - August 24,1997 Performed during Cycle 9

5. Complete installation for Work Month 39 - November 30,1997 Performed during RF-10 1

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