05000305/LER-2005-014, Technical Specification LCO Not Entered for Diesel Generators Inoperable While in Refueling Shutdown

Technical Specification LCO Not Entered for Diesel Generators Inoperable While in Refueling Shutdown

ML052240252
Person / Time
Site:	Kewaunee
Issue date:	08/05/2005
From:	Gaffney M Dominion Energy Kewaunee
To:	Document Control Desk, Office of Nuclear Reactor Regulation
References
05-524 LER 05-014-00
Download: ML052240252 (6)

LER-2005-014, Technical Specification LCO Not Entered for Diesel Generators Inoperable While in Refueling Shutdown

Event date:
Report date:
Reporting criterion:	10 CFR 50.73(a)(2)(ii)(B), Unanalyzed Condition 10 CFR 50.73(a)(2)(ix)(A) 10 CFR 50.73(a)(2)(iii) 10 CFR 50.73(a)(2)(x) 10 CFR 50.73(a)(2)(iv)(A), System Actuation 10 CFR 50.73(a)(2)(v)(A), Loss of Safety Function - Shutdown the Reactor 10 CFR 50.73(a)(2)(v)(B), Loss of Safety Function - Remove Residual Heat 10 CFR 50.73(a)(2)(v), Loss of Safety Function 10 CFR 50.73(a)(2)(i)(A), Completion of TS Shutdown 10 CFR 50.73(a)(2)(i)(B), Prohibited by Technical Specifications 10 CFR 50.73(a)(2) 10 CFR 50.73(a)(2)(i) 10 CFR 50.73(a)(2)(viii)(A) 10 CFR 50.73(a)(2)(ii)(A), Seriously Degraded 10 CFR 50.73(a)(2)(viii)(B)
3052005014R00 - NRC Website

text

711)' Dominiolli Dominion Energy Kewaunee, Inc.

N490 Highway 42, Kewaunee, WI 54216-951 1 AUG 0 5 2005 U. S. Nuclear Regulatory Commission Attention: Document Control Desk Washington, DC 20555 Serial No.05-524 KPS/LIC/RR: RO Docket No.

50-305 License No. DPR-43 DOMINION ENERGY KEWAUNEE, INC.

KEWAUNEE POWER STATION LICENSEE EVENT REPORT LER 2005-014-00

Dear Sirs:

Pursuant to 10 CFR 50.73, Dominion Energy Kewaunee, Inc., hereby submits the following Licensee Event Report applicable to Kewaunee Power Station.

Report No. 50-305/LER 2005-014-00 This report has been reviewed by the Plant Operating Review Committee and will be forwarded to the Management Safety Review Committee for its review.

If you have any further questions, please contact Rick Repshas at (920) 388-8217.

Very truly yours,

,4 i

Michael G. Gaffney Site Vice President, Kewaunee Power Station Attachment Commitments made by this letter: None

') z

Serial No.05-524 Page 2 of 2 cc:

Mr. J. L. Caldwell Administrator Region IlIl U.S. Nuclear Regulatory Commission 2443 Warrenville Road Suite 210 Lisle, IL 60532-4352 Mr. J. F. Stang Project Manager U.S. Nuclear Regulatory Commission Mail Stop 0-8-H-4a Washington, D. C. 20555 Mr. S. C. Burton NRC Senior Resident Inspector Kewaunee Power Station

NRC FORM 366 U.S. NUCLEAR REGULATORY COMMISSION APPROVED BY OMB NO. 3150-0104 EXPIRES 6-30-2007 (6-2004)

Estimated burden per response to comply with this mandatory collection request: 50 hours5.787037e-4 days <br />0.0139 hours <br />8.267196e-5 weeks <br />1.9025e-5 months <br />.

Reported lessons learned are Incorporated Into the licensing process and fed back to industry.

LICENSEE EVENT REPORT (LER)

Send comments regarding burden estimate to the Records and FOIA/Privacy Service Branch I I(T-5 F52), U.S. Nuclear Regulatory Commission, Washington, DC 20555-0001, orbyinternete-(See efor required number of mail to lnfocollects@nrc.gov, and to the Desk Officer, Office of Information and Regulatory (See reverse forrequiredAffairs, NEOB-10202, (3150-0066), Office of Management and Budget, Washngton, DC20503.

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FACILITY NAME (1)

DOCKET NUMBER (2)

PAGE (3)

Kewaunee Power Station 05000305 1 of 4 TITLE (4)

Technical Specification LCO Not Entered for Diesel Generators Inoperable While In Refueling Shutdown EVENT DATE (5)

LER NUMBER (6)

REPORT DATE (7)

OTHER FACILITIES INVOLVED (8)

SEQUENTiAL REV FACILITY NAME DOCKET NUMBER MO DAY YEAR YEA NUMBER NO MO DAY YEAR 06 06 2005 2005 014 -

00 08 05 2005 FACILITY NAME DOCKET NUMBER OPERATING N

THIS REPORT IS SUBMITTED PURSUANT TO THE REQUIREMENTS OF 10 CFR,: (Check all that apply) (11)

MODE (9) 20.2201 (b) 20.2203(a)(3)(ii) 50.73(a)(2)(ii)(B) l_

50.73(a)(2)(ix)(A)

POWER 20.2201(d) l 20.2203(a)(4) l 50.73(a)(2)(iii)

__ 50.73(a)(2)(x)

LEVEL (10) 000 20.2203(a)(1) 50.36(c)(1)(i)(A) 50.73(a)(2)(iv)(A)

_73.71 (a)(4) 20.2203(a)(2)

__ 50.36(c)(1)(ii)(A) 50.73(a)(2)(v)(A) 73.71 (a)(5) 20.2203(a)(2)(ii) 50.36(c)(2) 50.73(a)(2)(v)(B)

OTHER 20.2203(a)(2)(iii) 50.46(a)(3)(ii) 50.73(a)(2)(v)(C)

Specify In Abstract below or In 20.2203(a)(2)(iv)

= 50.73(a)(2)(i)(A) 50.73(a)(2)(v)(D) 20.2203(a)(2)(v)

X 50.73(a)(2)(i)(B) 50.73(a)(2)(vit) 20.2203(a)(2)(vi) 50.73(a)(2)(i)(C) 50.73(a)(2)(viii)(A) 20.2203(a)(3)(i) 50.73(a)(2)(ii)(A) 50.73(a)(2)(viii)(B)

LICENSEE CONTACT FOR THIS LER (12)

NAME TELEPHONE NUMBER (Include Area Code)

Richard Repshas (920) 388-8217 COMPLETE ONE LINE FOR EACH COMPONENT FAILURE DESCRIBED IN THIS REPORT (13)

MANU-REPORTABLE l MANU-REPORTABLE

CAUSE

SYSTEM COMPONENT FACTURER TO EPIX

CAUSE

SYSTEM COMPONENT FACTURER TO EPIX.

SUPPLEMENTAL REPORT EXPECTED (14)

EXPECTED MONTH DAY YEAR SUBMISSION 0

0 20 X

YES (If yes, complete EXPECTED SUBMISSION DATE).

NO DATE (15) l08 l

30 2005 ABSTRACT On June 7, 2005 with the unit in refueling shutdown mode, it was identified that Technical Specification (TS) operability was not applied correctly for the impact of tornado missiles and wind on Emergency Diesel Generator (EDG) equipment. It was not recognized that one train of EDG equipment was required to support the Residual Heat Removal system (RHR) whenever the RHR system is required to be operable. Evaluations that were performed revealed tornado impacts on various EDG components could render the EDGs inoperable.

At that time the RHR system should have been declared inoperable and a Limiting Condition for Operation entered. The initial operability concern was identified on March 24, 2005 for the EDG engine exhaust ductwork.

On this date the EDGs were determined to be capable of starting and assuming bus loads. It was also determined that they were not required to be operable during the station's current plant mode of refueling shutdown. The cause of this event was a misinterpretation of TS for auxiliary electrical systems during specific plant modes. Once the EDGs were determined to be inoperable, both RHR trains should have been declared inoperable. The RHR trains were available providing decay heat removal and the EDGs were available as a support system for RHR. This occurrence does not constitute a safety system functional failure.U.S. NUCLEAR REGULATORY COMMISSION (1-2001)

LICENSEE EVENT REPORT (LER)

TEXT CONTINUATION FACILITY NAME (1)

DOCKET NUMBER 2 LER NUMBER (6)

PAGE (3) ff lSEQUENTIAL l

EVISION Kewaunee Power Station 05000305 BYEAR SUEA NUMBER 2 of 4 2005 014 00 TEXT (If more space is required, use additional copies of NRC Form 366A) (17)

Event Description

On June 7,2005 with the unit in a refueling shutdown condition, it was identified that the Technical Specifications (TS) for the A and B Diesel Generator (EDG) [DG] operability were not applied correctly. The EDGs are required for supporting the Residual Heat Removal (RHR) [BP] system whenever the RHR system is required to be operable. Evaluations performed while the unit was in a refueling shutdown condition showed tornado impacts on various EDG components could render the EDGs inoperable. RHR was not declared inoperable and the Limiting Condition for Operation was not entered at this time.

This issue was identified to the Licensee by the site Senior Resident Inspector.

An operability concern was identified on March 24, 2005 for the EDG engine exhaust ductwork [DUCT]. A walk-down was being conducted in the Kewaunee Power Station Turbine Building [NM], as part of an evaluation of the Turbine Building response to design basis tornado winds. As described in the Kewaunee Power Station Updated Safety Analysis Report (USAR) Appendix B, sections of sheet metal panel [PL] siding on the Turbine Building are designed to blow out / blow in due to tornado wind loading. However, loss of this siding would expose the Class 3 portion EDG exhaust ductwork to tornado wind loads. The response of the sheet metal panels would be that the ductwork could be subjected to full design basis tornado force.

Exposure to tornado winds would likely result in deformation of the ductwork for each EDG possibly impacting EDG operation (reference Kewaunee Power Station LER 2005-005).

At the time, the EDGs were determined to be capable of starting and assuming the current bus loads but not being required to be operable in the current plant mode (refueling shutdown) per TS 3.7.

Further evaluation was performed on April 19, 2005 and it was determined the EDG exhaust ductwork was also susceptible to turbine and tornado missiles. Again, it was identified that the EDGs were not required to be operable in the current plant conditions (refueling shutdown) and the issue required resolution prior to the unit exceeding hot shutdown condition.

A second EDG component issue was identified on June 1, 2005. A probabilistic tornado missile evaluation was performed for EDG fuel oil tank [TK] vent lines as part of an extent of condition review for equipment response to the design basis tornado winds. The initial results of the evaluation indicated all four vents could be struck and damaged by a tornado missile to the point they would adversely affect EDG operation.

Deformation of the EDG fuel oil tank vent line could possibly restrict air flow to the tank leading to damage of the tank from the vacuum induced by the lowering fuel oil level. This could adversely affect the operation of the EDG.

Again, the EDGs were considered not required to be operable in the refueling shutdown mode per TS 3.7.

Subsequently, additional tornado missile analysis was performed for the EDG fuel oil tank vent lines using plant specific tornado hazard data. The revised evaluation indicated acceptable results.U.S. NUCLEAR REGULATORY COMMISSION I(1-2001 )

LICENSEE EVENT REPORT (LER)

TEXT CONTINUATION FACILITY NAME (1)

DOCKET NUMBER (2)

LER NUMBER (6)

PAGE 3 YEA SEQUENTIAL IREVISION Kewaunee Power Station 05000305 YER l NUMBER l NUMBER 3 of 4 2005 014 00 TEXT (Ifmore space is required, use additional copies of NRC Form 366A) (17)

Event Analysis

This condition is being reported in accordance with 10 CFR 50.73(a)(2)(i)(B), "Any operation or condition which was prohibited by the plant's Technical Specifications."

The mode applicability for TS 3.7, Auxiliary Electrical Systems, was misinterpreted. TS 3.7 applies to the availability of electrical power for the operation of plant auxiliaries to provide safe reactor operation and continuing availability of engineered safety features. It was assumed TS 3.7.c had the same mode applicability as TS 3.7.a, which is that the reactor shall not be made critical unless a specific number of electrical power supplies are available.

TS 3.7.c states the following:

3.7.c. When its normal or emergency power source is inoperable, a system, train or component may be considered OPERABLE for the purpose of satisfying the requirements of its applicable LIMITING CONDITION FOR OPERATION, provided:

1.

Its corresponding normal or emergency power source is OPERABLE; and

2. Its redundant system, train or component is OPERABLE.

The intent of the specification is to follow TS 3.7.c during all modes of operation.

With the A and B EDGs inoperable due to potential susceptibility of tornado missiles and wind damaging the exhaust ductwork or fuel oil tank vents, the two RHR trains were also required to be declared inoperable.

There was minimal safety significance as the RHR trains were available, although not operable due to the EDGs being inoperable as a result of the tornado design issues. Thus, RHR was providing decay heat removal and the EDGs were available as a support system for RHR. Per TS 3.1.2.B.2: If one RHR train is inoperable, then corrective action shall be taken immediately to return it to the operable status. From March 24, 2005 actions were in progress to perform evaluations and implement modifications so the EDG systems would meet tornado protection.

This occurrence does not constitute a safety system functional failure.

Cause

An apparent cause evaluation is in progress to determine the cause and full scope of corrective actions.

Following completion of the apparent cause, a supplement to this LER will be submitted.

Corrective Actions

Direction was provided to Operations Department personnel to follow TS section 3.7.c during all plant operating modes.U.S. NUCLEAR REGULATORY COMMISSION (1.2001)

LICENSEE EVENT REPORT (LER)

TEXT CONTINUATION FACILITY NAME (1)

DOCKET NUMBER (2)

LER NUMBER (6)

PAGE (3)

I I

SEQUENTIAL REVISION Kewaunee Power Station 05000305 ER NUMBER l

NUMBER 4 of 4 1 2005 014 00 TEXT (If more space is required, use additional copies of NRC Form 366A) (17)

Similar Events

A review of previous outages over the last three years did not identify the occurrence of any similar events.