05000293/LER-2008-001, Regarding Failure to Meet Technical Specification Requirements for Secondary Containment

Regarding Failure to Meet Technical Specification Requirements for Secondary Containment

ML080780502
Person / Time
Site:	Pilgrim
Issue date:	03/07/2008
From:	Bronson K Entergy Nuclear Operations
To:	Document Control Desk, Office of Nuclear Reactor Regulation
References
2.08.016 LER 08-001-00
Download: ML080780502 (6)

LER-2008-001, Regarding Failure to Meet Technical Specification Requirements for Secondary Containment

Event date:
Report date:
Reporting criterion:	10 CFR 50.73(a)(2)(i) 10 CFR 50.73(a)(2)(vii), Common Cause Inoperability 10 CFR 50.73(a)(2)(ii)(A), Seriously Degraded 10 CFR 50.73(a)(2)(viii)(A) 10 CFR 50.73(a)(2)(ii)(B), Unanalyzed Condition 10 CFR 50.73(a)(2)(viii)(B) 10 CFR 50.73(a)(2)(iii) 10 CFR 50.73(a)(2)(ix)(A) 10 CFR 50.73(a)(2)(iv)(A), System Actuation 10 CFR 50.73(a)(2)(x) 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)(i)(A), Completion of TS Shutdown 10 CFR 50.73(a)(2)(v), Loss of Safety Function 10 CFR 50.73(a)(2)(i)(B), Prohibited by Technical Specifications
2932008001R00 - NRC Website

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SEn tergy Entergy Nuclear Operations, Inc.

Pilgrim Nuclear Power Station 600 Rocky Hill Road Plymouth, MA 02360 Kevin H. Bronson Site Vice President March 7, 2008 U.S. Nuclear Regulatory Commission ATTN: Document Control Desk Washington, DC 20555

SUBJECT:

Entergy Nuclear Operations, Inc.

Pilgrim Nuclear Power Station Docket No: 50-293 License No. DPR-35 Licensee Event Report 2008-001 -00 LETTER NUMBER:

2.08.016

Dear Sir or Madam:

The enclosed Licensee Event Report (LER) 2008-001-00, "Failure to meet Technical Specification requirements for Secondary Containment' is submitted in accordance with 10 CFR 50.73.

This letter contains no commitments.

Please do not hesitate to contact Joseph Lynch, (508) 830-8403, if there are any questions regarding this submittal.

Sincerely, Kevin H Bronson FXM/dal Enclosure cc:

Mr. James S. Kim, Project Manager Plant Licensing Branch I-1 Division of Operator Reactor Licensing Office of Nuclear Reactor Regulation U.S. Nuclear Regulatory Commission One White Flint North 4D9A 11555 Rockville Pike Rockville, MD 20852 INPO Records 700 Galleria Parkway Atlanta, GA 30399-5957 Mr. Samuel J. Collins Regional Administrator, Region 1 U.S. Nuclear Regulator Commission 475 Allendale Road King of Prussia, PA 19406 Senior Resident Inspector Pilgrim Nuclear Power Station

NRC Form 366 U.S. NUCLEAR REGULATORY COMMISSION Approved by OMB: No. 3150-0104 Expires: 08/31/2010 (9-2007)

Estimated burden per response to comply with this mandatory information EEVENT REPORT (LER) collection request: 80 hrs. Reported lessons learned are incorporated into the LICENSEE Elicensing process and fed back to industry. Send comments regarding burden estimate to the Records and FOIA/Privacy Service Branch (T-5 F52). U.S.

Nuclear Regulatory Commission, Washington, DC 20555-0001, or by internet e-mail to infocollects@nrc.gov, and to the Desk Officer, Office of Information and Regulatory Affairs, NEOB-10202, (3150-0104), Office of Management and Budget, Washington, DC 20503.

If a means used to impose and information collection does not display a currently valid control number, the NRC may not conduct or sponsor, and a person is not required to respond to, theinformation collection.

3. PAGE PILGRIM NUCLEAR POWER STATION 05000-293 1 of 5

4. TITLE Failure to Meet Technical Specification Requirements for Secondary Containment

5. EVENT DATE

6. LER NUMBER

7. REPORT DATE)

8. OTHER FACILITIES INVOLVED SEQUENTIAL NUMBER REVISION FACILITY NAME DOCKET MONTH DAY YEAR YEAR NUMBER MONTH DAY' YEAR N/A NUMBER 05000 FACILITY NAME DOCKET 01 10 2008 2008 001 00 03 07 2008 N/A NUMBER R05000 9, OPERATING MODE

11. THIS REPORT IS SUBMITTED PURSUANT TO THE REQUIREMENTS OF 10 CFR: (Check one or more) 20.2201(b)

.22.2203(a)(3)(i) 50.73(a)(2)(i)(C) 50.73(a)(2)(vii)

N 22.2202(d) 20.2203(a)(3)(ii) 50.73(a)(2)(ii)(A) 50.73(a)(2)(viii)(A) 20.2203(a)(1) 20.2203(a)(4) 50.73(a)(2)(ii)(B) 50.73(a)(2)(viii)(B) 20.2203(a)(2)(i) 50.36(3)(1 )(i)(A) 50.73(a)(2)(iii) 50.73(a)(2)(ix)(A) 20.2203(a)(2)(ii) 50.36(3)(1 )(ii)(A) 50.73(a)(2)(iv)(A) 50.73(a)(2)(x)

10. Power Level 20.2203(a)(2)(iii) 50.36(c)(2) 50.73(a)(2)(v)(A) 73.71 (a)(4) 20.2203(a)(2)(iv) 50.46(a)(3)(ii) 50.73(a)(2)(v)(B) 73.71(a)(5) 100 20.2203(a)(2)(v) 50.73(a)(2)(i)(A) 50.73(a)(2)(v)(C)

OTHER 20.2203(a)(2)(vi)

X 50.73(a)(2)(i)(B)

• 50.73(a)(2)(v)(D)

Specify in Abstract below or in Technical Specification (TS) Limiting Condition for Operation (LCO) 3.7.C.1 requires, in part, that whenever the reactor is critical, secondary containment integrity must be maintained. TS Section 1.0 defines secondary containment integrity and requires as one of its conditions that all automatic ventilation system valves must be operable or secured in the closed position.

EVENT DESCRIPTION

On January 10, 2008 damper AO-N-78 failed to go fully closed on demand. In the close position, AO-N-78 had a one-half inch gap opening across two of the four damper blades. After the test the damper was re-opened and normal ventilation system operation was restored.

On January 14, 2008 a Maintenance Supervisor initiated WO 00135566 to repair damper AO-N-78. During the work order screening review it was recognized that the damper may be inoperable in its present configuration.

This concern was forwarded to the Control Room Shift Supervisor for operability review. The System Engineer was contacted to evaluate the damper's gap opening area. The damper gap was determined to exceed the limit allowed per Calculation No. C1 5.0.3381, Allowable Secondary Containment System Leakage Area and Gaps at Doors. The damper was declared inoperable and the LCO action for TS 3.7.C.2.a was entered. Work activities were immediately initiated to repair the damper. Repairs were completed and damper operability was restored on January 14, 2008 at approximately 1830 hours0.0212 days <br />0.508 hours <br />0.00303 weeks <br />6.96315e-4 months <br />.

CAUSE

The direct cause of the event was failure of the AO-N-78 damper to close. Troubleshooting by maintenance mechanics found that the damper blades were being stopped from closing fully by what appeared to be interference from the blade edge seal (jamb seal). The damper could be manually fully closed by moving the external linkage in the closed direction. This indicated that the actuator piston was not resting on its mechanical stop and blade travel was being stopped prior to full closure. The end seals were then inspected and re-cleaned. After re-cleaning the edge seal surfaces the damper was stroked several times, successfully fully closing each time. It appears that dirt/grime deposits on the edge seal surfaces increased the blade edge to edge seal surface friction enough to prevent the actuator from being able to fully close the damper. The actuator spring could not supply the necessary force to overcome the additional friction to fully close the damper or actuator output force has decreased over time such that it did not supply the necessary force to fully close the damper under fouled edge seal conditions.

NU.S. NUCLEAR REGULATORY COMMISSION (9-2007)

LICENSEE EVENT REPORT (LER)

CONTINUATION SHEET

6. LER NUMBER

3. PAGE SEQUENTIAL REVISION YEAR NUMBER NUMBER PILGRIM NUCLEAR POWER STATION 05000-293 2008 001 00 4 of 5 TEXT (If more space is required, use additional copies of NRC Form 366A) (17)

The cause of the failure to notify the Control Room was determined to be the result of unclear procedure instructions and inadequate assignment of test procedure reporting responsibilities. On January 10, 2008, maintenance was working WO 51534380. The work order was to inspect each RBICS isolation damper to determine sealing capability. Damper AO-N-78 was tested and found not to fully close when given a close signal from the control switch in the Main Control Room. The top and bottom blades had approximately a one-half inch gap between blade and blade stop when damper position indication indicated full closed.

Results of this finding were not reported to Operations until January 14, 2008 due to misunderstanding of the inspection acceptance criteria and lack of identified deficiency reporting requirements. It appears that since this damper was previously found to not fully close but was still considered operable on April 03, 2007, the present condition was also thought to be acceptable. Results were recorded in the work order and in Procedure 8.7.3, Attachment 1. WO 00135566 was initiated on January 14, 2008 to repair AO-N-

78. It was during the WO screening process on January 14, 2008 that it was recognized that AO-N-78 and the SCS may be inoperable.

CORRECTIVE ACTION

Corrective action taken included repairing AO-N-78. The damper was repaired and verified to go fully closed on January 14 at approximately 1830 hours0.0212 days <br />0.508 hours <br />0.00303 weeks <br />6.96315e-4 months <br />. An extent of condition review was performed and determined that other Reactor Building isolation dampers were operable.

Corrective actions planned to prevent future damper failures include development of enhanced damper maintenance procedure instruction, establishment of a damper maintenance repetitive task, and initiation of a work order to overhaul the RBCIS isolation damper actuators.

Corrective actions planned to prevent failure to notify the Control Room of damper testing problems includes action to update on-line damper inspection procedures to address clear acceptance criteria and requirements for immediate corrective action. In addition, action will be taken to conduct event discussions with maintenance, operations, and engineering personnel. The focus of these discussions is to address pre-job brief adequacy, test failure criteria, reporting-requirements, and requirements to ensure that sufficient detail is included in maintenance work packages.

These actions are being tracked in the Corrective Action Program (CR-PNP-2008-140 and CR-PNP-2008-143).

SAFETY CONSEQUENCES

The event posed no threat to public health and safety.

The plant was operating at 100% power prior to and during the time period when AO-N-78 failed to fully close and required repair. All other secondary containment isolation dampers were operable during this time period.

Failure of AO-N-78 to fully close on 1/10/08 would not have prevented the RBICS from performing its isolation function since the in-series damper (AO-N-79) in the same ventilation penetration was operable and capable of fully closing. This is apparent because AO-N-79 was demonstrated to fully close when tested January 10, 2008 and again on January 14, 2008. Thus the Reactor Building ventilation penetration opening would have been sealed by closure of AO-N-79 had secondary containment isolation been required.

Technical Specification 3.7.C requires that the secondary containment be operable in the RUN mode. The Secondary Containment integrity definition was not satisfied during this time period.U.S. NUCLEAR REGULATORY COMMISSION (9-2007)

LICENSEE EVENT REPORT (LER)

CONTINUATION SHEET

6. LER NUMBER

3. PAGE SEQUENTIAL REVISION YEAR NUMBER NUMBER PILGRIM NUCLEAR POWER STATION 05000-293 2008 001 00 5 of 5 TEXT (It more space is required, use additional copies of NRC Form 366A) (17)

Technical Specification definition for Secondary Containment Integrity means that the reactor building is intact and the following conditions are met:

1.

At least one door in each access opening is closed,

2.

The standby gas treatment system is operable,

3.

All automatic ventilation system isolation valves are operable or secured in the isolated position.

Only item 3 was not satisfied during the period between January 10 and 14, 2008. However, the redundant damper in the same ventilation penetration pathway was operable and would have isolated in response to a Secondary Containment Isolation signal. On January 14, 2008 action was taken to restore secondary containment integrity. AO-N-79 was closed until AO-N-78 was repaired and returned to operable status.

REPORTABILITY

This report was submitted in accordance with 10 CFR 50.73(a)(2)(i)(B).

SIMILARITY TO PREVIOUS EVENTS A review was conducted of Pilgrim Station LERs since 1974. The review identified a similar event that occurred in 1985. LER 85-18 addressed an event where a Secondary Containment damper (AO-N-90) would not fully close and compensatory actions were not taken for nineteen (19) hours. This event was reported as an event where Technical Specifications were not satisfied.

ENERGY INDUSTRY IDENTIFICATION SYSTEM (EIIS) CODES The EIIS codes for this report are as follows:

COMPONENTS CODES Damper DMP SYSTEMS CODES Containment Leak System BD