IR 05000352/2013005
| ML14037A370 | |
| Person / Time | |
|---|---|
| Site: | Limerick  |
| Issue date: | 02/06/2014 |
| From: | Fred Bower Reactor Projects Region 1 Branch 4 |
| To: | Pacilio M Exelon Generation Co, Exelon Nuclear |
| BOWER, FL | |
| References | |
| IR-13-005 | |
| Download: ML14037A370 (43) | |
Text
{{#Wiki_filter:UNITED STATES NUCLEAR REGULATORY COMMISSION ary 6, 2014
SUBJECT:
LIMERICK GENERATING STATION - NRC INTEGRATED INSPECTION REPORT 05000352/2013005 AND 05000353/2013005
Dear Mr. Pacilio:
On December 31, 2013, the U.S. Nuclear Regulatory Commission (NRC) completed an inspection at your Limerick Generating Station (LGS), Units 1 and 2. The enclosed inspection report documents the inspection results, which were discussed on January 10, 2014, with Mr. T. Dougherty, Site Vice President, and other members of your staff.
The inspection examined activities conducted under your license as they relate to safety and compliance with the Commissions rules and regulations and with the conditions of your license.
The inspectors reviewed selected procedures and records, observed activities, and interviewed personnel.
NRC inspectors identified one self-revealing finding of very low safety significance (Green) during this inspection. The finding did not involve a violation of NRC requirements. If you disagree with the cross-cutting aspect assignment in this report, you should provide a response within 30 days of the date of this inspection report, with the basis for your disagreement, to the Regional Administrator, Region I; and the NRC Resident Inspector at the LGS.
As a result of the Safety Culture Common Language Initiative, the terminology and coding of cross-cutting aspects were revised beginning in calendar year 2014. New cross-cutting aspects identified in calendar year 2014 will be coded under the latest revision to Inspection Manual Chapter (IMC) 0310. Cross-cutting aspects identified in the last six months of 2013 using the previous terminology will be converted to the latest revision in accordance with the cross-reference in IMC 0310. The revised cross-cutting aspects will be evaluated for cross-cutting themes and potential substantive cross-cutting issues in accordance with IMC 0305 starting with the calendar year 2014 mid-cycle assessment review.
In accordance with 10 Code of Federal Regulations (CFR) 2.390 of the NRCs Rules of Practice, a copy of this letter, its enclosure, and your response (if any) will be available electronically for public inspection in the NRC Public Document Room or from the Publicly Available Records component of the NRCs Agencywide Documents Access System (ADAMS).
ADAMS is accessible from the NRC website at http://www.nrc.gov/reading-rm/adams.html (the Public Electronic Reading Room).
Sincerely, /RA/ Fred L. Bower, III, Chief Reactor Projects Branch 4 Division of Reactor Projects Docket Nos.: 50-352, 50-353 License Nos.: NPF-39, NPF-85
Enclosure:
Inspection Report 05000352/2013005 and 05000353/2013005 w/Attachment: Supplemental Information
REGION I== Docket Nos.: 50-352, 50-353 License Nos.: NPF-39, NPF-85 Report No.: 05000352/2013005 and 05000353/2013005 Licensee: Exelon Generation Company, LLC Facility: Limerick Generating Station, Units 1 & 2 Location: Sanatoga, PA 19464 Dates: October 1, 2013 through December 31, 2013 Inspectors: E. DiPaolo, Senior Resident Inspector J. Hawkins, Resident Inspector J. Ayala, Resident Inspector (Acting) R. Nimitz, Senior Health Physicist K. Mangan, Senior Reactor Inspector T. Burns, Reactor Inspector J. DAntonio, Senior Operations Engineer B. Fuller, Senior Operations Engineer S. Chaudhary, Reactor Inspector Approved By: Fred Bower, Chief Reactor Projects Branch 4 Division of Reactor Projects Enclosure
SUMMARY
IR 05000352/2013005, 05000353/2013005; 10/1/2013-12/31/2013; Limerick Generating Station (LGS), Units 1 and 2; Followup of Events and Notices of Enforcement Discretion.
This report covered a three month period of inspection by resident inspectors and announced inspections performed by regional inspectors. Inspectors identified one finding of very low safety significance (Green). The significance of most findings is indicated by their color (i.e., greater than Green, or Green, White, Yellow, Red) and determined using Inspection Manual Chapter (IMC) 0609, Significance Determination Process, dated June 2, 2011. Cross-cutting aspects are determined using IMC 0310, Components Within Cross-Cutting Areas, dated October 28, 2011. All violations of Nuclear Regulatory Commission (NRC) requirements are dispositioned in accordance with the NRCs Enforcement Policy, dated January 28. 2013. The NRCs program for overseeing the safe operation of commercial nuclear power reactors is described in NRC Technical Report Designation (NUREG)-1649, Reactor Oversight Process, Revision 4.
Cornerstone: Barrier Integrity
- Green.
The inspectors identified a self-revealing finding (FIN) of very low safety significance (Green) for Exelons failure to appropriately prioritize work activities associated with a degraded Unit 2 magnetic switch for a secondary containment airlock door in accordance with Exelon procedure WC-AA-106, Work Screening and Processing. This resulted in both airlock doors being opened simultaneously due to equipment degradation and resulted in a momentary loss of reactor enclosure secondary containment integrity.
The failure of the station to properly prioritize the work order for the defective magnetic switch for the Unit 2 313 elevation reactor building-to-reactor building air supply room access airlock doors was a performance deficiency that was reasonably within Exelons ability to foresee and correct and could have been prevented. This was caused by not performing a site impact review of reportability clarifications made by NUREG 1022, Event Report Guidelines 10 CFR 50.72 and 50.73, Revision 3. The performance deficiency was also contrary to Exelons procedure for work screening and processing. The finding was determined to be more than minor because it was associated with the Barrier Integrity cornerstone attribute of structures, systems, and components (SSC) and Barrier Performance (doors and instrumentation) and affected the cornerstone objective of providing reasonable assurance that physical design barriers (secondary containment)protect the public from radionuclide releases caused by accidents or events. Specifically, opening two reactor building airlock doors at the same time did not maintain reasonable assurance that the secondary containment would be capable of performing its safety function in the event of a reactor accident. The finding was determined to be self-revealing because it was revealed through the receipt of an alarm in the main control room which required no active and deliberate observation by Exelon personnel. The finding was determined to be of very low safety significance (Green) in accordance with Appendix A of IMC 0609, "Significance Determination Process for Findings At-Power." Specifically, the finding only represents a degradation of the radiological barrier function provided by the secondary containment airlock doors. Exelon entered the issue into the corrective action program (CAP) as Issue Report (IR) 1553563. Corrective actions performed or planned included repairing the magnetic switch, verifying that the corrective maintenance backlog did not contain any other issues involving the airlock door indicating lights, developing a periodic routine test of the airlock door indicating circuits, and performing a site impact review of the changes in NUREG 1022, Revision 3.
This finding had a cross-cutting aspect in the area of Human Performance, Resources, because Exelon did not ensure that resources were available to minimize preventative maintenance deferrals and ensure maintenance and engineering backlogs were low enough to ensure that safety is maintained [H.2(a)]. Specifically, Exelon deferred implementation of the work order several times over a three year period which resulted in secondary containment becoming inoperable on September 3, 2013. (Section 4OA3)
Other Findings
None.
REPORT DETAILS
Summary of Plant Status
Unit 1 began the inspection period at 100 percent power. On December 12, 2013, operators conducted a planned power reduction to approximately 60 percent to facilitate main steam valve testing, main turbine valve testing, control rod scram time testing, fuel channel distortion testing, and to repair a cooling water leak on the A main condensate pump. Operators returned the unit to 100 percent power on December 16, 2013, and Unit 1 remained at or near 100 percent power for the remainder of the inspection period.
Unit 2 began the inspection period at 100 percent power. On December 7, 2013, operators conducted a planned power reduction to approximately 92 percent to facilitate main turbine valve testing. Operators returned the unit to 100 percent power on December 8, 2013, and Unit 2 remained at or near 100 percent power for the remainder of the inspection period.
REACTOR SAFETY
Cornerstones: Initiating Events, Mitigating Systems, and Barrier Integrity
1R01 Adverse Weather Protection
.1 Readiness for Seasonal Extreme Weather Conditions
a. Inspection Scope
On December 11, 2013, the inspectors performed a review of Exelons readiness for the onset of seasonal cold weather. The review focused on the sites emergency diesel generators (EDGs) and equipment located in the sites Spray Pond Pump House (ie., emergency service water and residual heat removal service water pumps). The inspectors reviewed the Updated Final Safety Analysis Report (UFSAR), Technical Specifications (TS), control room logs, and the corrective action program to determine what temperatures or other seasonal weather could challenge these systems, and to ensure Exelon personnel had adequately prepared for these challenges. The inspectors reviewed station procedures, including Exelons seasonal weather preparation procedure and applicable operating procedures. The inspectors performed walkdowns of the selected systems to ensure station personnel identified issues that could challenge the operability of the systems during cold weather conditions. Documents reviewed for each section of this inspection report are listed in the Attachment.
b. Findings
No findings were identified.
.2 Readiness for Impending Adverse Weather Conditions
a. Inspection Scope
On October 7, 2013, the inspectors reviewed Exelon staffs preparations in advance of and during a Tornado Watch issued by the National Weather Service for Montgomery County, Pennsylvania. The inspectors performed walkdowns of equipment that could be effected by high winds including the main transformer areas and the EDGs to verify that potential missile objects were secure. The inspectors verified that Exelon personnel performed preparations in accordance with severe weather procedures.
b. Findings
No findings were identified. ==1R04 Equipment Alignment Partial System Walkdowns (71111.04 - 5 samples)
a. Inspection Scope
== The inspectors performed partial walkdowns of the following systems: Unit 2 high pressure coolant injection (HPCI) system (risk significant system)following the discovery of a degraded system flexible conduit (IR 1564080) on October 2, 2013 10 bus and 101 offsite power source when the 20 bus and 201 offsite source were out-of-service for planned maintenance on October 7, 2013 Unit 2 reactor core isolation cooling (RCIC) system when Unit 2 HPCI system was unavailable due to a flow controller issue (IR 1572132) on October 21, 2013 Unit 1 RCIC system (risk significant system) following return to service following RCIC vacuum breaker testing on November 26, 2013 Unit 2 HPCI system (risk significant system) following return to service following HPCI system simulated automatic actuation testing on December 19, 2013 The inspectors selected these systems based on their risk-significance relative to the reactor safety cornerstones at the time they were inspected. The inspectors reviewed applicable operating procedures, system diagrams, the UFSAR, TS, work orders, issue reports (IR), and the impact of ongoing work activities on redundant trains of equipment in order to identify conditions that could have impacted system performance of their intended safety functions. The inspectors also performed field walkdowns of accessible portions of the systems to verify system components and support equipment were aligned correctly and were operable. The inspectors examined the material condition of the components and observed operating parameters of equipment to verify that there were no deficiencies. The inspectors also reviewed whether Exelon staff had properly identified equipment issues and entered them into the corrective action program for resolution with the appropriate significance characterization.
b. Findings
No findings were identified. ==1R05 Fire Protection