IR 05000277/2009008
| ML092600662 | |
| Person / Time | |
|---|---|
| Site: | Peach Bottom  |
| Issue date: | 09/17/2009 |
| From: | Racquel Powell NRC/RGN-I/DRP/PB7 |
| To: | Pardee C Exelon Generation Co, Exelon Nuclear |
| POWELL, RJ | |
| References | |
| IR-09-008 | |
| Download: ML092600662 (26) | |
Text
UNITED STATES NUCLEAR REGULATORY COMMISSION ber 17, 2009
SUBJECT:
PEACH BOTTOM ATOMIC POWER STATION, UNITS 2 AND 3 -
NRC PROBLEM IDENTIFICATION AND RESOLUTION INSPECTION REPORT 05000277/2009008 AND 05000278/2009008
Dear Mr. Pardee:
On August 7, 2009, the United States Nuclear Regulatory Commission (NRC) completed an inspection at your Peach Bottom Atomic Power Station, Units 2 and 3. The enclosed report documents the inspection results discussed on August 7, 2009, with Mr. G. Stathes and other members of your staff.
This inspection was an examination of activities conducted under your license as they relate to the identification and resolution of problems and compliance with the Commission=s rules and regulations and the conditions of your license. Within these areas, the inspection involved examination of selected procedures and representative records, observations of activities, and interviews with personnel.
The inspectors concluded that Exelon was generally effective in identifying, evaluating, and resolving problems. Exelon personnel identified problems and entered them into the corrective action program at a low threshold. Exelon prioritized and evaluated issues commensurate with the safety significance of the problems and corrective actions were generally implemented in a timely manner.
Based on the results of this inspection one finding of very low safety significance (Green) was identified. The finding was associated with inadequate corrective action implementation and involved a violation of NRC requirements. The NRC is treating this finding as a non-cited violation (NCV) consistent with Section VI.A.1 of the NRC Enforcement Policy because of the very low safety significance of the violation and because it was entered into your corrective action program. If you contest this non-cited violation, you should provide a response within 30 days of the date of this inspection report, with the basis for your denial, to the Nuclear Regulatory Commission, ATTN.: Document Control Desk, Washington DC 20555-0001; with copies to the Regional Administrator, Region 1; the Director, Office of Enforcement, United States Nuclear Regulatory Commission, Washington, DC 20555-0001; and the NRC Resident Inspector at Peach Bottom Atomic Power Station. In addition, if you disagree with the characterization of any finding 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 Peach Bottom Atomic Power Station. The information you provide will be considered in accordance with Inspection Manual Chapter 0305.
In accordance with Title 10 of the Code of Federal Regulations, Part 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 (PARS) component of the NRCs document system (ADAMS).
ADAMS is accessible from the NRC Web Site at http://www.nrc.gov/reading-rm/adams.html (the Public Electronic Reading Room).
Sincerely,
/RA/
Raymond J. Powell, Chief Technical Support & Assessment Branch Division of Reactor Projects Docket Nos: 50-277, 50-278 License Nos: DPR-44, DPR-56 Enclosure: Inspection Report 05000277/2009008 and 05000278/2009008 w/Attachment: Supplemental Information cc w/encl:
C. Crane, President and Chief Operating Officer, Exelon Corporation M. Pacilio, Chief Operating Officer, Exelon Nuclear W. Maguire, Site Vice President, Peach Bottom J. Grimes, Senior Vice President, Mid-Atlantic R. Hovey, Senior Vice President, Nuclear Oversight G. Stathes, Plant Manager, Peach Bottom J. Armstrong, Regulatory Assurance Manager, Peach Bottom J. Bardurski, Manager, Financial Control & Co-Owner Affairs P. Navin, Director, Operations P. Cowan, Director, Licensing D. Helker, Licensing K. Jury, Vice President, Licensing and Regulatory Affairs J. Bradley Fewell, Associate General Counsel, Exelon T. Wasong, Director, Training Correspondence Control Desk D. Allard, Director, Bureau of Radiation Protection, PA Department of Environmental Protection S. Gray, Administrator, Maryland Power Plant Research Program
SUMMARY OF FINDINGS
IR 05000277/2008009 and 05000278/2008009; 07/20/2009 - 08/07/2009; Peach Bottom Atomic
Power Station, Units 2 and 3; Identification and Resolution of Problems, One finding was identified in the area of corrective action program effectiveness.
This NRC team inspection was performed by two resident inspectors and three regional inspectors. One finding of very low safety significance (Green) was identified by the NRC during this inspection and was classified as a non-cited violation (NCV). The significance of most findings is indicated by their color (Green, White, Yellow, Red) using NRC Inspection Manual Chapter (IMC) 0609, ASignificance Determination Process@ (SDP). The cross-cutting aspect was determined using IMC 0305, Operating Reactor Assessment Program. Findings for which the SDP does not apply may be Green or assigned a severity level after NRC management review. The NRC=s program for overseeing the safe operation of commercial nuclear power reactors is described in NUREG-1649, AReactor Oversight Process,@ Revision 4, dated December 2006.
Identification and Resolution of Problems The inspectors concluded that Exelon was generally effective in identifying, evaluating and resolving problems. Specifically, Exelon personnel identified problems, entered them into the corrective action program at a low threshold, and prioritized issues commensurate with the safety significance. For most cases, Exelon appropriately screened issues for operability and reportability and performed causal analyses that appropriately considered extent of condition, generic issues, and previous occurrences. Corrective actions taken to address the problems identified in Exelons corrective action process were typically implemented in a timely manner.
However, for one issue reviewed by the inspectors, inadequate implementation of corrective actions resulted in one NRC-identified finding.
The inspectors also concluded that, in general, Exelon adequately identified, reviewed, and applied relevant industry operating experience to Peach Bottom Atomic Power Station (PBAPS)operations. In addition, based on those items selected for review by the inspectors, Exelons audits and self-assessments were thorough and probing.
Based on the interviews the inspectors conducted over the course of the inspection, observations of plant activities, and reviews of individual corrective action program and employee concerns program issues, the inspectors did not identify any concerns that site personnel were not willing to raise safety issues nor did they identify conditions that could have had a negative impact on the sites safety conscious work environment.
Cornerstone: Mitigating Systems
- Green.
The inspectors identified a non-cited violation (NCV) of 10 CFR 50 Appendix B,
Criterion XVI, Corrective Action, for failure to identify and correct a condition adverse to quality. Specifically, in March 2009, Exelon did not take adequate corrective action to address a procedure deficiency and to ensure that grease inappropriately applied to Cutler Hammer direct current (DC) contactor pivot pins, in an unknown number of DC breakers in the high pressure coolant injection (HPCI) and reactor core isolation cooling (RCIC) systems at Unit 2 and 3, would be identified and removed in a timely manner. Because the grease could harden over time and cause inadequate DC breaker performance, the inspectors determined that this condition, if left uncorrected, could prevent certain Units 2 and 3 HPCI and RCIC system valves from performing their safety-related function. Exelon entered this issue into their corrective action program as issue report (IR) 950438 and IR 950439
.
The finding affected the Mitigating Systems cornerstone and was determined to be more than minor because the condition, if left uncorrected, could have become a more significant safety concern. By not requiring, by procedure, the removal of all grease from the affected Cutler Hammer DC contactor pivot pins, Exelon did not ensure that all of the potentially affected DC motor-operated valves in the Unit 2 and Unit 3 HPCI and RCIC systems would be available to perform their design functions if called upon. The inspectors evaluated this finding using Phase I of Manual Chapter 0609 and determined the finding to be of very low safety significance (Green) because it was not a design or qualification deficiency confirmed not to result in loss of operability or functionality, did not represent a loss of system or train safety function, and was not potentially risk significant due to external events. This finding has a cross-cutting aspect in the area of problem identification and resolution, corrective action program, because Exelon failed to take appropriate corrective actions to address a safety issue in a timely manner, commensurate with the safety-significance and complexity P.1(d). Specifically, Exelon did not take appropriate corrective actions to ensure that grease inappropriately applied to Cutler Hammer DC contactor pivot pins would be, by procedure, identified and removed in a timely manner. (Section 4OA2.1.c)
Other Findings
None.
REPORT DETAILS
OTHER ACTIVITIES (OA)
4OA2 Problem Identification and Resolution
.1 Assessment of the Corrective Action Program (CAP) Effectiveness
a. Inspection Scope
The inspectors reviewed the procedures that describe Exelons CAP at Peach Bottom Atomic Power Station (PBAPS). Exelon identified problems for evaluation and resolution by initiating and processing issue reports (IRs) using the Passport web-based computer application. Problems were screened for operability and reportability, categorized based on significance (1 to 5) and assigned a level for the cause evaluation (A to D) based on significance and the level of uncertainty for the cause. When work was necessary to correct a problem, the work request (PIMS) system was used to generate action requests (ARs) or work orders. As such, at PBAPS, the work management and engineering change processes were part of the CAP and were utilized to correct identified conditions when deemed appropriate.
To assess the effectiveness of the CAP at PBAPS, the inspectors reviewed performance in three primary areas: problem identification, prioritization and evaluation, and corrective action (CA) implementation. The inspectors compared performance in these three areas to the requirements and standards contained in 10 CFR 50 Appendix B Criterion XVI, Corrective Action, and Exelon procedure, LS-AA-125, Corrective Action Program Procedure. The scope of the inspectors review for each of these areas at PBAPS is described below. The IRs and other documents reviewed for the inspection are listed in the Attachment.
Effectiveness of Problem Identification The inspectors reviewed a sample of plan of the day (POD) meeting packages and meeting minutes for a sample of plant operations review committee (PORC), nuclear safety review board (NSRB), and maintenance rule expert panel meetings. The inspectors also attended a number of POD, management review committee (MRC), and station ownership committee (SOC) meetings. The inspectors verified that identified issues discussed at these meetings were entered into the CAP for evaluation and CA, as appropriate.
The inspectors reviewed the condition of the emergency diesel generators (EDGs), the emergency service water (ESW) system, the high pressure coolant injection (HPCI)system, and the primary containment isolation (PCI) system. The inspectors reviewed system health reports, a sample of completed preventative and corrective maintenance work orders, and completed surveillance test procedures. The inspectors also completed a field walkdown of the accessible portions of the EDG and ESW systems.
The inspectors verified that conditions adverse to quality identified through this review were entered into the CAP, as appropriate.
The inspectors reviewed a random sample of security, operations, chemistry, radiation protection, and outage control center logs. The inspectors verified that problems identified in these logs were entered into the CAP as appropriate.
The inspectors reviewed the March 25, 2008, PBAPS Pre-Exercise Emergency Response Organization Drill Report issued on April 24, 2008, and the 2008 Peach Bottom Station-Only Drill and Exercise Performance Drill Series Findings and Observations Report issued on July 24, 2008. The inspectors verified that drill performance deficiencies identified in these reports were entered into the CAP as appropriate.
The inspectors reviewed the results of Exelon periodic trend analyses conducted in accordance with LS-AA-125-1005, Coding and Analysis Manual, and LS-AA-126-1007, Performance Improvement Toolbox. The inspectors verified that identified trends discussed in selected quarterly reviews of station focus areas were entered into the CAP for further evaluation and CA as appropriate. The inspectors also verified the applicability of trend codes entered for a sample of CAP IRs.
The inspectors also verified that issues identified through internal self-assessments and audits and the operating experience (OE) program were entered into the CAP for evaluation and CA, as appropriate.
Effectiveness of Prioritization and Evaluation of Issues The inspectors reviewed the evaluation and prioritization for a sample of IRs issued since the last NRC problem identification and resolution inspection that was performed in May 2007. The inspectors considered risk insights from the stations risk analysis and ensured that the selected IRs were appropriately distributed across the seven cornerstones of safety and the emergency preparedness, engineering, maintenance, operations, physical security, and radiation safety functional areas. Inspectors samples in this area were focused on but not limited to the offsite power system, the EDGs, the primary containment and PCI systems, and the high pressure service water (HPSW) and ESW systems.
To assess Exelons effectiveness in the prioritization of issues, the inspectors observed three daily IR screening meetings conducted by the SOC during the onsite weeks and reviewed the packages for a random sample of MRC meetings conducted since the last inspection. During the daily IR screening meetings, the SOC reviewed new IRs for prioritization and assignment. Subsequently, the MRC reviewed the IRs and made priority adjustments as necessary.
The issues and IRs reviewed encompassed the full range of evaluations, including root cause analyses (RCA), apparent cause evaluations (ACEs), and common cause analyses (CCAs). IRs that were assigned lower levels of significance that did not include formal cause evaluations were also reviewed by the inspectors to ensure they were appropriately classified. The inspectors review included the appropriateness of the assigned significance, the scope and depth of the causal analysis, and the timeliness of resolution. The inspectors assessed whether the evaluations identified likely causes for the issues and whether Exelon developed appropriate CAs to address the identified causes. Further, the inspectors reviewed equipment operability determinations, reportability assessments, and extent-of-condition reviews for selected problems to verify these processes adequately addressed equipment operability, reporting of issues to the NRC, and the extent of problems. During the onsite weeks, the inspectors also observed MRC meetings during which Exelon managers reviewed completed RCAs, as well as selected ACEs and CA assignments.
Effectiveness of CAs The inspectors verified completion of CAs for a sample of IRs issued since the last NRC problem identification and resolution inspection that was performed in May 2007. The inspectors considered risk insights from the stations risk analysis and ensured that the selected IRs were appropriately distributed across the seven cornerstones of safety and the emergency preparedness, engineering, maintenance, operations, physical security, and radiation safety functional areas. Inspectors samples in this area were focused on but not limited to the offsite power system, the EDGs, the primary containment and PCI systems, and the HPSW and ESW systems. CAs were verified to have been completed through documentation and, in some cases, field walkdowns. The inspectors also reviewed a sample of CAs for IRs greater than two years old. The inspectors selected these items based on risk significance, verified appropriate interim actions were in place, and that the basis for not completing the specified CAs was appropriately documented and well supported.
The inspectors reviewed IRs for adverse trends and repetitive problems to determine whether CAs were effective in addressing the broader issues. The inspectors reviewed Exelons timeliness in implementing CAs and effectiveness in precluding recurrence for significant conditions adverse to quality. The inspectors also reviewed a sample of IRs associated with selected non-cited violations (NCVs), findings, and licensee event reports, to verify that Exelon personnel properly evaluated and resolved these issues. In addition, the CA review was expanded to five years to evaluate Exelons actions related to torus shell corrosion control, raw water system corrosion control, and age-related valve performance issues.
b. Assessment Effectiveness of Problem Identification Based on the samples selected, the inspectors determined that Exelon identified problems and entered them into the CAP at a low threshold. Exelon personnel at PBAPS initiated approximately 29,000 IRs between May 2007 and June 2009. During the inspection the inspectors reviewed approximately 200 IRs written during that same period. Based on this review and the review of the items discussed in the scope above, the inspectors determined that in most cases, Exelon appropriately documented identified problems in IRs that resulted in an evaluation and/or CA assignment or completion.
The inspectors also verified that Exelon trended equipment and programmatic issues in order to identify emerging issues at a low level. The trending process at PBAPS for the period reviewed was controlled by Exelon procedures LS-AA-125-1005, Coding and Analysis Manual, Revision 6 and LS-AA-126-1007, Performance Improvement Toolbox, Revision 0. The inspectors concluded that, in accordance with Exelon procedures, Exelon personnel identified emerging trends at a low level and used the CAP to conduct evaluations and implement CAs when appropriate. The inspectors, based on the samples selected, also did not identify trends or repetitive issues that Exelon had not self-identified through its trending process.
Effectiveness of Prioritization and Evaluation of Issues The inspectors determined, based on the samples selected that Exelon, in general, appropriately prioritized and evaluated issues commensurate with the safety significance of the identified problem. IRs were screened for operability and reportability, categorized by significance, and assigned to a department for evaluation and resolution. The various IR screening and management review groups considered human performance issues, radiological safety concerns, repetitiveness, adverse trends, and potential impact on the safety conscious work environment (SCWE) during the conduct of reviews.
Items reviewed by the inspectors during the inspection were categorized for evaluation and resolution commensurate with the significance of the issues. Guidance provided by Exelon procedure LS-AA-120, Issue Identification and Screening Process, for categorization appeared sufficient to ensure consistent implementation based on the sample of IRs reviewed by the inspectors. In general, issues were appropriately screened and prioritized commensurate with their safety significance.
The inspectors reviewed four root cause analyses, eight apparent cause analyses, three common cause evaluations, and approximately 16 work group evaluations. For the evaluations reviewed, the inspectors noted that Exelons evaluations were generally thorough and appropriately considered extent of condition, generic issues, and previous occurrences.
Exelon procedure LS-AA-120, Issue Identification and Screening Process, stated that the operating shift must evaluate whether or not the reported deficiency affected the operability of the system and document the basis for the determination. In addition, in cases where additional information was necessary to support the basis for operability, an action must be assigned to complete the more formal evaluation. For each of the IR cause analyses reviewed, the inspectors reviewed the completed operability evaluations and determined that, in general, the evaluations were appropriately performed.
However, in one case the inspectors identified an issue regarding the adequacy of the documented operability evaluation.
Specifically, IR 871970 was written to document that the 2C core spray room cooler did not meet its fouling factor acceptance criteria during testing conducted in December 2008. The inspectors reviewed the evaluation performed by Exelon to assess the impact of the higher-than-expected fouling factor on the ability of the cooler to perform its safety function. The factors that impacted the ability of the cooler to perform its safety function included ESW flow rate, river water temperature, and the heat exchanger fouling factor. Exelons evaluation of cooler operability used the minimum assumed ESW flow rate, the design river temperature, and the fouling factor calculated during the most recent thermal performance test. Based on this evaluation, Exelon lowered the maximum allowable river temperature required for cooler operability.
The inspectors determined that using the fouling factor calculated at the time of testing was a non-conservative assumption. Specifically, between the last unit cooler test (in December 2007) and the current test (in December 2008), the fouling factor had increased by approximately six percent. The inspectors determined that Exelon should have used these results to project the additional cooler fouling that could occur between the December 2008 test and the next scheduled test (in December 2009), and then calculate maximum allowable river temperature from this projected fouling factor.
By not accounting for the additional fouling that could occur before the next scheduled cleaning or thermal performance test, Exelon did not ensure that appropriate CAs could be taken to correct a condition adverse to quality (CAQ) and maintain the cooler operable. The inspectors determined that this was a performance deficiency. The issue was determined to be minor, and therefore not subject to enforcement action in accordance with the NRCs Enforcement Policy. Specifically, because there was significant margin between actual measured ESW flow to the cooler and the minimum design ESW flow to the cooler, such that using a more conservatively calculated fouling factor would not have required action to be taken to ensure cooler operability. Exelon documented this concern in IR 949567.
Effectiveness of CAs The inspectors concluded that CAs for identified deficiencies were generally implemented in a timely and adequate manner. The inspectors also concluded that Exelon performed in-depth effectiveness reviews for significant issues to verify that implemented CAs were effective. However, the inspectors review of the IR disposition documentation and verification of corrective CA implementation through a review of work orders and discussions with personnel involved identified one issue and one finding of very low safety significance regarding CA implementation. The issue is described below and the finding is described in section 4OA2.1c.
IR 588335 was written by Exelon to evaluate their untimely response to IR 584506 that documented the presence of corrosion products on a weld in ESW piping. Exelon eventually determined that these corrosion products were the result of a through-wall leak, completed an evaluation in accordance with ASME code case N-513 that determined the leak did not affect the operability of the pipe or ESW system, and then repaired the leak. However, the timeliness of this CA was questioned by management and a quick human performance investigation (QHPI) was initiated under IR 588335.
The QHPI determined that when the SOC reviewed IR 584506, they directed the operations department to inspect the affected pipes condition during the next ESW pump and valve flow surveillance test to confirm the initial operability call that there was not a through-wall leak. The QHPI determined that the operations department tracked this action as part of shift turnover, but, due to various human performance errors including inadequate pre-job briefs, shift turnover communication, and work scheduling, did not complete the necessary observation as originally directed. This delayed the identification of the through-wall leak on the pipe.
The inspectors determined that Exelon immediately completed CAs to address the inadequate pre-job briefs and shift turnover communication and initiated a CA assignment (coded as a CA - an action taken or planned that restores a CAQ to an acceptable condition) to address the work scheduling issues. The specific assignment description stated, Develop a method for assuring that SOC follow-up items that are evolution/milestone dependent are more robustly tracked to completion. The completion notes documented in the IR stated that there were already many ways available for SOC to close items, and that these methods should be used at the discretion of the SOC. The assignment was closed by the evaluator without developing any additional methods. The inspectors determined that this did not meet the intent of the CA, that in accordance with LS-AA-125, Corrective Action Program (CAP)
Procedure, step 4.8.1, required the responsible department heads approval, and that for this instance no approval was given.
The inspectors determined that the failure of the evaluator to obtain the proper approvals was a performance deficiency associated with the Mitigating System cornerstone. The deficiency was not more than minor because the inspectors determined that it was not a precursor to a significant event; if left uncorrected it would not lead to a more significant safety concern; and it did not adversely affect the Mitigating Systems cornerstone objective of ensuring the availability, reliability and capability of systems that response to initiating events to prevent undesirable consequences. Specifically, Exelon determined that had the appropriate approval been sought for the change of intent for the CA, it would have been approved. In addition, as stated above the station took immediate corrective action to address the inadequate pre-job briefs and shift turnover communication associated with this issue. Exelon documented this concern in IR 949578.
c. Findings
Introduction:
The inspectors identified a Green NCV of 10 CFR 50 Appendix B, Criterion XVI, Corrective Action, for Exelons failure to identify and correct a CAQ. Specifically, in March 2009, Exelon did not take adequate corrective action to address a procedure deficiency and to ensure that grease inappropriately applied to Cutler Hammer direct current (DC) contactor pivot pins, in an unknown number of DC breakers in the high pressure coolant injection (HPCI) and reactor core isolation cooling (RCIC) systems at Unit 2 and 3, would be identified and removed in a timely manner. Because the grease could harden over time and cause inadequate DC breaker performance, the inspectors determined that this condition, if left uncorrected, could prevent certain Unit 2 and 3 HPCI and RCIC system valves from performing their safety-related function.
Description:
On March 24, 2009, Exelon performed diagnostic testing of motor-operated valve (MOV) MO-2-23-017, the Unit 2 HPCI condensate storage tank (CST) suction valve. During the test, it was noted that the measured drop-out time for the open contactor inside the valves DC breaker exceeded its established acceptance criteria.
Because the open contactor was responsible for stopping valve movement in the open direction, the delayed contactor operation resulted in the valve disc driving too far into its open seat. Exelon performed an engineering evaluation to determine whether the over-travel condition had resulted in damage to the valve components or motor operator.
Exelon determined that the torque generated by the over-travel condition was below design limits for the valve, and therefore the valve remained operable.
Exelons initial investigations determined that the slow contactor operation was caused by grease that had been previously applied to the contactor pivot pin during preventative maintenance and then subsequently hardened with age. Further evaluation, including discussions with the vendor, revealed that grease should not have been applied to the contactor pivot pin, and any grease that was applied should be removed. If the contactor pivot pin required lubrication, Cutler Hammer publication 13719 stated that these pins should be occasionally lubricated with oil. Exelon discovered that the preventative maintenance (PM) procedure did not provide guidance regarding lubrication of DC contactor pivot pins and that on occasion, technicians had applied grease to the pins if contactor response was sluggish.
To address the identified procedure deficiency, Exelon revised the PM procedure, M-057-008, 250 Volt DC Breaker Assembly Inspection and Maintenance. Specifically, Exelon added steps 5.1.5 through 5.1.7, which directed technicians to examine the pivot pin for evidence of degraded lubricant, and IF degraded lubricant is present, THEN clean the pin and apply oil. The inspectors determined that this procedure revision did not adequately address the issue, because Exelons cause analysis had determined that all grease must be removed from the DC contactor pivot pins. The PM procedure, as revised, allowed for technicians to assess the grease condition and remove it only if it was determined to be degraded. The inspectors concluded that the procedure should have required technicians to remove the grease regardless of its condition. Exelon entered this issue into the CAP as IR 950438.
The inspectors determined that the lack of adequate procedural guidance and the use of grease to lubricate the contactor pivot pins in DC breakers in the Unit 2 and Unit 3 HPCI and RCIC systems were CAQs. These conditions, if left uncorrected, could become a more significant safety concern in that the operability of safety-related MOVs, specifically the ability to shut or open, could have been affected in that previously applied grease may not be removed due to an inadequate preventive maintenance procedure change.
Exelon determined that there were 48 breakers installed in the Unit 2 and Unit 3 HPCI and RCIC systems that were potentially susceptible to this condition. However, it was unknown how many contactor pivot pins actually had grease applied to them due to lack of documentation in the maintenance records.
In June 2009, Exelon inspected five of the remaining 48 potentially affected breakers and identified that no grease was applied to the contactors associated with those breakers. Exelon also reviewed the maintenance history for the Unit 2 HPCI CST suction valve and breaker, which had experienced the slow contactor operation on March 24, and determined that the last breaker PM was performed 11 years ago, and the last valve diagnostic test was performed six years ago. Because both of these activities provide indication of proper contactor operation, Exelon determined that the contactors most at risk for grease hardening would be those whose valves had not been diagnostic tested and whose breakers had not received PMs in the last six years.
Exelon reviewed the maintenance history of the remaining 43 valves and determined that only one other valve met these criteria. As a result, Exelon moved up the breaker PM for this valve to early 2010 to inspect for the presence of grease. Because all of the remaining susceptible breakers had received a breaker PM or satisfactory MOV diagnostic test within the last six years, and the associated valves for each breaker were stroked periodically, the inspectors determined that there was no immediate safety concern associated with this issue. In addition, based on discussions with the inspectors, Exelon initiated IR 950439 to evaluate the future operability of the remaining breakers to ensure that an appropriate timeline for inspecting the breakers was established.
Analysis:
Exelons failure to establish adequate CAs to ensure grease was, by procedure, removed from Cutler Hammer DC contactor pivot pins was a performance deficiency. The finding affected the Mitigating Systems cornerstone and was determined to be more than minor because the condition, if left uncorrected, could have become a more significant safety concern. Specifically, by not requiring the removal of all grease from the affected Cutler Hammer DC contactor pivot pins, Exelon did not ensure that all of the potentially affected DC MOVs in the Unit 2 and Unit 3 HPCI and RCIC systems would be available to perform their design functions if called upon. Although the Unit 2 HPCI CST suction valve, MO-2-23-017, was not damaged by the backseating condition that resulted from the delayed contactor operation, it could not be assured that the outcome would be the same for all of the valves whose breakers had the grease incorrectly applied. The inspectors evaluated this finding using Phase I of Manual Chapter 0609 and determined the finding to be of very low safety significance (Green)because it was not a design or qualification deficiency confirmed not to result in loss of operability or functionality, did not represent a loss of system or train safety function, and was not potentially risk significant due to external events.
This finding has a cross-cutting aspect in the area of problem identification and resolution, CAP, because Exelon failed to take appropriate CAs to address a safety issue in a timely manner, commensurate with the safety-significance and complexity
P.1(d). Specifically, Exelon did not take appropriate CAs to ensure that grease inappropriately applied to Cutler Hammer DC contactor pivot pins would be, by procedure, identified and removed in a timely manner.
Enforcement:
10 CFR 50, Appendix B, Criterion XVI, Corrective Action, requires, in part, that measures shall be established to assure that conditions adverse to quality, are promptly identified and corrected. Contrary to the above, Exelon did not take adequate CA to ensure that a CAQ was promptly identified and corrected. Specifically, by not requiring, by procedure, the removal of all grease from the Cutler Hammer DC contactor pivot pins, Exelon did not ensure that the remaining DC MOVs in the Unit 2 and Unit 3 HPCI and RCIC systems would be available to perform their design functions if required.
Because this finding was determined to be of very low safety significance (Green) and has been entered into Exelons CAP (IR 950438 and IR 950439), it is being treated as a non-cited violation, consistent with Section VI.A.1 of the NRC Enforcement Policy. (NCV 05000277, 278/2009008-01, Failure to Take Timely and Adequate CAs for Grease Applied to DC Contactors.)
.2 Assessment of the Use of OE
a. Inspection Scope
The inspectors selected a sample of industry OE issues to confirm that Exelon evaluated the OE information for applicability to PBAPS and took appropriate actions when warranted. The inspectors reviewed OE documents to verify that Exelon appropriately considered the underlying problems associated with the issues for resolution via their CAP. A list of the documents reviewed is included in the Attachment.
b. Assessment The inspectors determined, based on the sample of OE reviewed, that Exelon appropriately considered industry OE information for applicability, and used the information for corrective and preventive actions to identify and prevent similar issues.
The inspectors assessed that, in general, OE was appropriately applied and lessons learned were communicated and incorporated into plant operations.
However, the inspectors identified one issue of concern related to OE where the evaluation of applicability of an OE item to PBAPS was not adequate. Specifically, the inspectors reviewed IRs 469346 and 593531, which documented Exelons review of issues documented in NRC IN 2007-05, Vertical Deep Draft Pump Shaft and Coupling Failures. It discussed OE related to vertical deep draft pump shaft and coupling failures due to intergranular stress corrosion cracking (IGSCC). Exelons procedure LS-AA-115-1003, Processing of Significance Level 3 OPEX Evaluations, directed that the quality review of the closeout documentation for the OE review should ensure that the documentation stands alone and is clear enough to identify that the review was completed satisfactorily.
The inspectors identified that Exelons evaluation concluded that their ESW pumps were not susceptible to the concerns described in the OE because the Peach Bottom ESW pumps were standby pumps and therefore were not subject to the same levels of stress as the pumps described in the OE. The inspectors questioned the adequacy of this evaluation because some of the pumps discussed in the OE also were standby pumps.
The inspectors determined that the documented evaluation was inadequate in that it was based on an unconfirmed assumption, and the inspectors review of the OE determined that the assumption was invalid. This was a performance deficiency associated with the Mitigating Systems cornerstone. The issue was not more than minor because the inspectors determined, through discussions with Exelon, that historically Exelon has not identified evidence of IGSCC on the standby service water pumps. Exelon documented this issue of concern in IR 950683 and also planned to inspect the 3C HPSW pump for evidence of IGSCC when the pump is removed for replacement in November 2009 to confirm the adequacy of the OE evaluation and corrective actions.
c. Findings
No findings of significance were identified.
.3 Assessment of Self-Assessments and Audits
a. Inspection Scope
The inspectors reviewed a sample of audits, including the most recent audit of the CAP, departmental self-assessments, and assessments performed by independent organizations. These reviews were performed to determine if problems identified through these assessments were entered into the CAP, when appropriate, and whether CAs were initiated to address identified deficiencies. The effectiveness of the audits and assessments was evaluated by comparing audit and assessment results against self-revealing and NRC-identified observations made during the inspection. A list of documents reviewed is included in the Attachment to this report.
b. Assessment The inspectors concluded that self-assessments, audits, and other internal Exelon assessments were generally critical, probing, thorough, and effective in identifying issues. The inspectors observed that these audits and self-assessments were completed in a methodical manner by personnel knowledgeable in the subject. The audits and self-assessments were completed to a sufficient depth to identify issues that were entered into the CAP for evaluation. In general, CAs associated with the identified issues were implemented commensurate with their safety significance.
c. Findings
No findings of significance were identified.
4. Assessment of SCWE
a. Inspection Scope
The inspectors reviewed the SCWE at PBAPS through conduct of the following activities.
- During interviews with staff personnel, the inspectors questioned individuals regarding: willingness to raise safety concerns, knowledge of the avenues available for raising safety concerns, the effectiveness of actions taken by management to foster a SCWE at the site, and knowledge of other individuals who had experienced a negative reaction for raising a safety concern. The inspectors interviewed approximately 40 personnel in a cross section of organizations.
- The inspectors reviewed implementation of the site employee concerns program (ECP). The inspectors compared the number and type of issues documented in the PBAPS ECP between May of 2007 to June of 2009 to the number and type of issues documented as PBAPS NRC allegations for that same period. The inspectors reviewed the site procedure for conducting ECP investigations and reviewed a sample of ECP files to assess the programs effectiveness at addressing potential safety issues.
- The inspectors reviewed the results of the site nuclear safety culture survey performed in November 2008 and the CAs identified by the assessment that Exelon performed when it reviewed the survey results. This was the only safety culture assessment performed after the SCWE inspection that was done in March 2008.
That inspection was performed in accordance with the Deviation Memorandum (ML073320344) that was issued to authorize additional inspection of Exelons actions to resolve work environment issues related to inattentive security officers that were identified at PBAPS in September 2007. The results for the inspection were documented in IR 05000277/2008405 and 05000278/2008405 (ML081490058).
b. Assessment Based on interviews and reviews of the CAP and the ECP, the inspectors determined that in general site personnel were willing to identify and raise safety issues. All persons interviewed demonstrated an adequate knowledge of the avenues available for raising safety concerns including CAP and ECP. In addition, comparisons of PBAPS ECP files to NRC allegation information did not identify any impediments to the free flow of information at PBAPS.
c. Findings
No findings of significance were identified.
4OA6 Meetings, Including Exit
On August 7, 2009, the inspectors presented the inspection results to Mr. G. Stathes, Plant Manager, and other members of the PBAPS staff. The inspectors confirmed that proprietary information was reviewed by inspectors during the course of the inspection, that any proprietary information that was reviewed was returned to Exelon, and that the content of this report includes no proprietary information.
ATTACHMENT:
SUPPLEMENTAL INFORMATION
KEY POINTS OF CONTACT
Licensee personnel
- W. Maguire, Site Vice President
- G. Stathes, Plant Manager
- J. Armstrong, Manager, Regulatory Assurance
- E. Flick, Director, Engineering
- P. Navin, Director, Work Management
- L. Lucas, Manager, Chemistry
- R. Franssen, Director, Operations
- R. Holmes, Manager, Radiation Protection
- D. DeBoer, Director, Security
- T. Wasong, Director, Training
- K. Pederson, Corporate Employee Concerns Program
- D. McClellan, Regulatory Assurance, Site CAPCO
- S. Minnick, Manager, Nuclear Oversight
- T. Basso, Director, Maintenance
LIST OF ITEMS OPENED, CLOSED, AND DISCUSSED
Opened and Closed
- 05000277, 278/2009008-01 NCV Failure to Take Adequate CAs for Grease Applied to DC Contactors (Section 4OA2.1.c.)