05000305/LER-2006-003, Re Residual Heat Removal Pumps Declared Inoperable Due to Flooding Vulnerability

Re Residual Heat Removal Pumps Declared Inoperable Due to Flooding Vulnerability

ML061920579
Person / Time
Site:	Kewaunee
Issue date:	07/05/2006
From:	Hartz L Dominion Energy Kewaunee
To:	Document Control Desk, Office of Nuclear Reactor Regulation
References
06-549 LER 06-003-00
Download: ML061920579 (5)

LER-2006-003, Re Residual Heat Removal Pumps Declared Inoperable Due to Flooding Vulnerability

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)(vii), Common Cause Inoperability 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)
3052006003R00 - NRC Website

text

N-1"~Dominion Dominion Energy Kewaunee, Inc.

N490 Highway 42, Kewaunee, WI 54216-9511 JUL 0 5 2006 U. S. Nuclear Regulatory Commission Attention: Document Control Desk Washington, DC 20555 Serial No.06-549 KPS/LIC/RR: RO Docket No.

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

KEWAUNEE POWER STATION LICENSEE EVENT REPORT 2006-003-00

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. 50-305/2006-003-00 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 Mr. Richard Repshas at (920) 388-8217.

Very truly yours, Leslie N. Hartz Site Vice President, Kewaunee Power Station Attachment Commitments made by this letter: NONE

Serial No.06-549 Page 2 of 2 cc:

Regional Administrator, Region III U.S. Nuclear Regulatory Commission 2443 Warrenville Road Suite 210 Lisle, IL 60532-4352 Mr. D. H. Jaffe Project Manager U.S. Nuclear Regulatory Commission Mail Stop O-7-D-1 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 (T-5 F52), U.S. Nuclear Regulatory Commission, Washington, DC 20555-=001, or byinternet e-(See reverse for required number of mail to lnfocollects@nrc.gov, and to the Desk Officer, Office of Information and Regulatory Affairs, NEOB-10202, (3150-0066), Office of Management and Budget, Washington, DC 20503.

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FACILITY NAME (1)

CKET NUMBER (2)

PAGE (3)

Kewaunee Power Station 7

05000305%:.

1 of 3

TITLE (4)

Residual Heat Removal Pumps Declared Inoperable Due to Flooding Vulnerability EVENT DATE (5)

LER NUMBER (6)

REPORT DATE (7)

OTHER FACILITIES INVOLVED (8)

SEQUENTIAL I REV FACILITY NAME DOCKET NUMBER MO DAY YEAR YEAR NUMBER NO MO DAY YEAR 05 05 2006 2006

-- 003 -- 00 07 05 2006 FACILITY NAME DOCKET NUMBER OPERATING N

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

MODE (9)

N 20.2201 (b) 20.2203(a)(3)(ii) 50.73(a)(2)(ii)(B) 50.73(a)(2)(ix)(A)

POWER 20.2201 (d) 20.2203(a)(4) 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)(i) 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)

X 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)(vii) 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 Repshas1 (920) 388-8217 COMPLETE ONE LINE FOR EACH COMPONENT FAILURE DESCRIBED IN THIS REPORT (13)

MANU-REPORTABLE MANU-REPQRTABLE

CAUSE

SYSTEM COMPONENT FACTURER

CAUSE

SYSTEM COMPONENT FACTURER TO EPIX SUPPLEMENTAL REPORT EXPECTED (14)

EXPECTED MONTH DAY YEAR X

YES (If yes, complete EXPECTED SUBMISSION DATE).

DATE (is1) 10 26 2006 ABSTRACT On May 5, 2006 at 1600 CST in intermediate shutdown, the Kewaunee Power Station declared both trains of the residual heat removal (RHR) system inoperable due to internal flooding vulnerability caused by the possibility of non-seismically qualified pipe breaks during a seismic event. The RHR pumps are not protected from non-seismically qualified pipe breaks in the auxiliary building. The specific design criteria is stated in the Updated Safety Analysis Report Section B.5 'Protection of Class I Items' and states that "Class I items are protected against damage from Rupture of a pipe or tank resulting in serious flooding or excessive steam release to the extent that the Class I function is impaired." The two RHR trains are not separated in a manner that would prevent simultaneous damage to both trains from a failure of a non-seismically qualified pipe.

This event was reported under Event Number 42557 in accordance with 1 OCFR50.72(b)(3)(v)(B), "Any event that at the time of discovery could have prevented the fulfillment of the safety function of systems that are needed to remove residual heat."

This is being reported in accordance with 10 CFR 50.73(a)(2)(v)(B), "Any event or condition that could have prevented the fulfillment of the safety function of structures or systems that are needed to remove residual heat" and 10 CFR 50.73(a)(2)(i)(B), "Any condition which was prohibited by the plant's Technical Specifications."

Assessment of this issue is still under evaluation. Results of the assessment will be provided in a supplement to this LER. This is being reported as 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)

PACE (3)

Kewaunee Power Station 05000305 YEAR I

SEQUENTIAL REVISION NUMBER NUMBER 2 of 3 112006 003 00 TEXT (If more space is required, use additional copies of NRC Form 366A) (17)

Event Description

On May 5, 2006 at 1600 CST in intermediate shutdown, the Kewaunee Power Station declared both trains of the residual heat removal (RHR) system inoperable due to internal flooding vulnerability caused by the possibility of non-seismically qualified pipe [PSP] breaks during a seismic event. The RHR pumps [P] are not protected from non-seismically qualified pipe breaks in the auxiliary building. The specific design criteria is stated in the Updated Safety Analysis Report Section B.5 'Protection of Class I Items' and states that "Class I items are protected against damage from Rupture of a pipe or tank [TK] resulting in serious flooding or excessive steam release to the extent that the Class I function is impaired." The two RHR trains are not separated in a manner that would prevent simultaneous damage to both trains from a failure of a non-seismically qualified pipe.

The RHR pumps were declared inoperable when Kewaunee Power Station received the results of a Task Interface Agreement (TIA) from the Nuclear Regulatory Commission office of Nuclear Reactor Regulation titled, "Final Response to Task Interface Agreement 2005-10 Relating to Impact of Flooding on Residual Heat Removal (RHR) Pumps at Kewaunee Power Station (Task Interface Agreement (TIA) 2005-1 0)(TAC No.

MC8937)." Dominion Energy Kewaunee (DEK) continues to assess this TIA to determine its applicability.

This event was reported under Event Number 42557 in accordance with 1 OCFR50.72(b)(3)(v)(B), "Any event that at the time of discovery could have prevented the fulfillment of the safety function of systems that are needed to remove residual heat."

Event Analysis and Safety Significance:

This is being reported in accordance with 10 CFR 50.73(a)(2)(v)(B), "Any event or condition that could have prevented the fulfillment of the safety function of structures or systems that are needed to remove residual heat" and 10 CFR 50.73(a)(2)(i)(B), "Any operation or condition which was prohibited by the plant's Technical Specifications."

The station was in intermediate shutdown (average reactor coolant temperature greater than 200 degrees and less than 540 degrees Fahrenheit and zero percent fission power) when the condition was identified. Although both trains of residual heat removal pumps were inoperable, the Technical Specification requirement for decay heat removal capability was being met with two steam generators operable to remove decay heat.

The safety significance of this event is being assessed. DEK is continuing to review the TIA to determine its applicability to the station's design basis.

This is being reported as a safety system functional failure as an event or condition that could have prevented the fulfillment of the safety function of structures or systems needed to remove residual heat.

Cause

When the results of the review of the TIA are completed this LER will be updated.U.S. NUCLEAR REGULATORY COMMISSION (1-2001)

LICENSEE EVENT REPORT (LER)

TEXT CONTINUATION FACILITY NAME (1)

DOCKET NUMBER (2)

LER NUMBER (6)

PAGE (3)

Kewaunee Power Station 05000305 YEAR SEQUENTIAL REVISION 3 of 3 2006 003 00 TEXT (If more space is required, use additional copies of NRC Form 366A) (17)

Corrective Actions

1. A design change was completed to install residual heat removal pump flood barriers.

2. DEK is continuing to review the TIA to determine its applicability to the station's design basis.

Similar Events

LER 2005-004-01, Safe Shutdown Potentially Challenged By Unanalyzed Internal Flooding Events and Inadequate Design.