ML061420145

LER 99-014-03 for Virgil C. Summer Nuclear Station, Re Kaowool Fire Barriers Outside 10 CFR 50 Appendix R Design Basis

ML061420145
Person / Time
Site:	Summer
Issue date:	05/17/2006
From:	Archie J B South Carolina Electric & Gas Co
To:	Document Control Desk, Office of Nuclear Reactor Regulation
References
LER 99-014-03
Download: ML061420145 (4)

Text

Jeffrey B. Archie Vice President, Nuclear Operations 803.345.4214 A SCANA COMPANY May 17, 2006 Document Control Desk U. S. Nuclear Regulatory Commission Washington, DC 20555

Subject:

VIRGIL C. SUMMER NUCLEAR STATION DOCKET NO. 50-395 OPERATING LICENSE NO. NPF-12 LICENSEE EVENT REPORT (LER 1999-014-03)

KAOWOOL FIRE BARRIERS OUTSIDE 10CFR50 APPENDIX R DESIGN BASIS Attached is a revised Licensee Event Report, LER 1999-014-03, for the Virgil C.Summer Nuclear Station (VCSNS). This report updates the completion date for the long term corrective actions. This issue is being reported per 10 CFR 50.73(a)(2)(ii)(B).

Should you have any questions, please call Mr. Robert G. Sweet at (803) 345 -4080.Very truly yours, C)u Wr 'r34 Jeffrey B. Archie MWD/JBA/dr Attachment c: K. B. Marsh S. A. Byrne N. S. Cams J. H. Hamilton (w/o attachment)

R. J. White W. D. Travers R. E. Martin NRC Resident Inspector M. N. Browne K. M. Sutton D. L. Abstance P. Ledbetter EPIX Coordinator INPO Records Center J&H Marsh & McLennan NSRC RTS (C-99-1520)

File (818.07)DMS (RC-06-0100)

--&1-;?:'e;1 SCE&G I Virgil C. Summer Nuclear Station

• P.O. Box 88. Jenkinsville, South Carolina 29065 .T (803) 345.5209 .www.scana.com NRC FORM 366 U.S. NUCLEAR REGULATORY COMMISSION APPROVED BY OMB NO. 3150-0104 EXPIRES 0613012001 (6-1998) Estimated burden per response to comply with this mandatory information collection request: 50.0 hrs. Reported lessons learned are incorporated Into the licensing process and fed back to industry.

Forward comments regarding burden estimate to the Records Management Branch (T-6 F33), U.S. Nuclear LICENSEE EVENT REPORT (LER) R ulatory Commission, Washin on DC 20555-0001, and to the Paperwork Rugction Prec 3150- 6ffice of Management fand Budget, Washington, Dr2053. If an information collection does not display a currently valid OMB control number, the NRC may not conduct or sponsor, and a person is not required to respond to, the information collection.

FACILITY NAME (1) lDOCKET NUMBER (2) PAGE (3)Virgil C. Summer Nuclear Station 0 5 0 0 0 3 9 5 1 of 3 TITLE (4)Kaowool Fire Barriers Outside 1OCFR50 Appendix R Design Basis EVENT DATE (5) LER NUMBER (6 REPORT DAT7E mI OTHER FACILITIES INVOLVED (8)SEQUENTIAL REVISION FACILITY NAME DOCKET NUMBER MONTH DAY YEAR YEAR NUMBER NUMBER MONTH DAY YEAR I 05000 FACILITY NAME DOCKET NUMBER 12 29 99 1999-- 014 -- 03 5 17 2006 OPERATING THIS REPORT IS SUBMITTED PURSUANT TO THE REQUIREMENTS OF 10 CFR 4: (Check one or more) (11)MODE (9) 1 l20.2201(b)

I 20.2203(aX2Xv)

I 50.73(aX2X)I 50.73(aX2#01)

POWER 20.2203(a)(1)

I j20.2203(aX3X1)

X 150.73(a)(2XII) 50.73(a)(2)(i)

LEVEL (10) 100 -20.2203(aX2Xi)

_20.2203(aX3Xii) 1 50.73(a)(2Xiii) 73.71 4 0.2203(a)(2)(ii)

..J20.2203(a)X4) 50.73(aX2Xiv)

OTHER 20.2203(aX2)(;;)

l 50.36(CXI) l 50.73(aX2Xv)

Soecifv In Abstract below I 20.2203(aX2)(Iv)

50.36(cX2) 50.73(aX2Xv1i) orInf NRC FORM 366A LICENSEE CONTACT FOR THIS LER (12)NAME ITELEPHONE NUMBER (Include Area Code)R. G. Sweet I Manager, Nuclear Licensing l (8 0 3) 3 4 5 -4 0 8 0 COMPLETE ONE LINE FOR EACH COMPONENT FAILURE DESCRIBED IN THIS REPORT (13) _ I CAUSE SYSTEM COMPONENT MANUFACTURER TO EPIX MA CAUSE SYSTEM COMPONENT MANUFACTURER EP ROEPORTBL ITIEPORTBL B KP CBL5 BO15 l YES A IIII_ I SUPPLEMENTAL REPORT EXPECTED (14) j EXPECTED IMONTH DAY YEAR I YES omltNO E SUBMISSION A I Il(if yes, complete EXPECTED SUBMISSION DATE). I XII DATE (I5) IIII I ABSTRACT (Umit to 1400 spaces, I.e., approximately 15 single-spaced typewritten lines) (16)On December 28, 1999, Virgil C. Summer Nuclear Station (VCSNS) commissioned testing on Kaowool triple wrap fire barriers.

The testing was conducted to confirm the fire resistance rating of typical plant specific design considerations.

On December 29, 1999, engineering personnel determined, from a review of preliminary test data, that some as installed applications may not meet the current regulatory requirements for maintaining one train free of fire damage for one hour. Station Condition Evaluation Report (CER) 99-1520 was generated to document this event and to track actions for resolution.

As a result of this test, all surface mounted configurations, and 4" and larger conduit and 6" x 36" raceways suspended in open air, passed the 1 -hour fire rating. Some of the cables in 1 " conduit, 6" x 6" raceways, and air drop cables suspended in open air failed the Generic Letter (GL) 86-10, Supplement I megger when subjected to an ASTM E-1 19 fire test.VCSNS has implemented compensatory actions (fire watches) as a conservative measure, for all Kaowool Fire Barriers that are needed to achieve and maintain post-fire safe shutdown in accordance with Appendix R and 1OCFR50.48.

Adjustments to these compensatory actions will be based on the results of fiurther engineering evaluation, and the completion of plant modifications.

NRC FORM 366 (6-1998)

NRC FORM 366A U.S. NUCLEAR REGULATORY COMMISSION (6-1998)LICENSEE EVENT REPORT (LER)TEXT CONTINUATION FACILITY NAME (1) DOCKET NUMBER (2) LER NUMBER (6) PAGE (3)V. C. Summer Nuclear Station 05000395 NSEQUENTIR REVISION 2 of 3 1 1999 014 03 l TEXT (if more space is required, use additional copies of NRC Form 366A) (17)PLANT IDENTIFICATION Westinghouse

-Pressurized Water Reactor EQUIPMENT IDENTIFICATION Kaowool Fire Barrier for Electrical Cables IDENTIFICATION OF EVENT Testing of Kaowool triple wrap fire barriers demonstrates that some applications do not meet design requirements.

EVENT DATE December 29, 1999 REPORT DATE January 26, 2000 SUPPLEMENT 1 REPORT DATE April 1, 2000 REVISION 2 REPORT DATE July 1, 2003 REVISION 3 REPORT DATE May 17,2006 CONDITIONS PRIOR TO EVENT Mode 1, 100% power DESCRIPTION OF EVENT Virgil C. Summer Nuclear Station (VCSNS) commissioned fire-endurance testing to be performed on Kaowool triple wrap fire barriers on December 28, 1999. A large scale 1-hour test was conducted at the Omega Test Labs in San Antonio, Texas. The testing was conducted on representative sample conduits and cable trays, in typical VCSNS configurations, to confirm the fire resistance rating of these barriers and verify our existing design and licensing basis. This testing was being performed as a voluntary initiative at the request of the NRC as discussed in SECY 99-204, "Kaowool and FP-60 Fire Barriers." Engineering personnel determined, on December 29, 1999, that preliminary results indicate that some applications may not meet the current regulatory requirements for maintaining one train free of fire damage for a one hour duration (10 CFR 50 Appendix R, Section ll.G.2.)NRC Form 366A (6-1998)

I NRC FORM 366A U.S. NUCLEAR REGULATORY COMMISSION (6-1998)LICENSEE EVENT REPORT (LER)TEXT CONTINUATION FACILITY NAME (1) DOCKET NUMBER (2) LER NUMBER (6) PAGE (3)V. C. Summer Nuclear Station 05000395 SUMEN NRE 3 of 3 I II 1999 014 03I TEXT (If more space is required, use additional copies of NRC Form 366A) (17)ANALYSIS Some limited cable failures were identified.

The limited failures were experienced in small cable, conduit, and tray applications installed in open-air configurations (not running along wall or ceiling).

Other applications; large conduit, tray, and surface mounted conduit performed satisfactorily, based on a preliminary review of the test data.VCSNS has a total of 30 Kaowool triple wrap applications that are required for Appendix R. The 30 Kaowool applications are limited to 18 separate fire areas/zones.

Of the 18 fire areas, 14 have fire loads less than the current designed fire rating of the enclosure with the other four located in cable chases that have automatic fire suppression.

Additionally, 16 of the affected fire areas, have acceptable core damage frequency, as calculated during Phase 1 of the IPEEE evaluation, with the remaining 2 found acceptable during Phase 2 by fire modeling.

In four instances the air drop cables required an additional (2) layers of 1" Kaowool wrap and modifications (ECR-50205) to provide thermal masses above the tested configurations to protect these individual cables.IMMEDIATE ACTIONS VCSNS has implemented compensatory actions (roving fire watches) for all 30 Appendix R Kaowool triple wrap applications (18 fire areas/zones) as a conservative and precautionary measure.LONG TERM CORRECTIVE ACTIONS VCSNS has implemented modifications (ECR 50205), based on the results of the engineering evaluations to address affected areas by providing additional protection for exposed silicone foam barriers, exposed supports (potential thermal shorts), and the air drop cables. This change included evaluations resulting in 11 of the 30 Kaowool triple wrap applications meeting all design and licensing basis.VC Summer is currently implementing modifications to address the remaining 19 Kaowool applications.

Re-routing cables, adding suppression, and using qualified fire wrap material have been substantially implemented to address these applications.

These modifications are expected to be completed by December 31, 2006.NRC Form 366A (6-1998)