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| Quarter | Site | Title | Description | |
|---|---|---|---|---|
| 05000353/FIN-2015003-02 | 2015Q3 | Limerick | Inadequate Preventive Maintenance of the HPCI System Motor Control Center | A self-revealing Green NCV of TS 6.8.1.a, Procedures and Programs, occurred when Exelon inadequately maintained and implemented a preventive maintenance (PM) task for the 2DB-1-14 high pressure coolant injection (HPCI) direct current (DC) motor control center (MCC) cubicle. Specifically, PM procedure M-095-002, 250 VDC Westinghouse MCU Maintenance, Revision 6, was performed on the main compartment but was not performed on the auxiliary compartment of the 2DB-1-14 MCC cubicle. Subsequently, the 1A timetactor failed due to lack of cleaning and inspection, which led to a fire in the HPCI DC MCC. Exelons corrective actions included initiating issue report (IR) 2480166, replacing the affected components, and revising the PM task to perform future preventive maintenance on both the main and auxiliary compartments of the 2DB-1-14 cubicle. Exelon also conducted immediate extent of condition reviews and scheduled further reviews to ensure no similar conditions exist. This issue is more than minor because it was associated with the procedures quality attribute of the Mitigating Systems cornerstone, and adversely affected the cornerstone objective to ensure the reliability of systems that respond to initiating events to prevent undesirable consequences (i.e., core damage). Specifically, PM procedure M-095-002, 250 VDC Westinghouse MCU Maintenance, Revision 6, was not performed on both compartments of the 2DB-1-14 cubicle and caused the fire in the HPCI DC MCC that had the potential to affect HPCI system operation. Using IMC 0609, Significance Determination Process, Appendix A, Exhibit 2, Mitigating Systems Screening Questions, the inspectors determined that this finding was of very low safety significance (Green) because the finding was not a deficiency affecting the design or qualification of the HPCI system and the system maintained operability and functionality. Specifically, the affected portions of the HPCI system were a part of the HPCI vacuum tank condensate pump that is not required to ensure operability or functionality. The inspectors determined that the finding did not have a cross-cutting aspect because the PM task change did not occur within the last three years, and the inspectors did not conclude that the causal factors represented present Exelon performance. |
| 05000353/FIN-2015003-01 | 2015Q3 | Limerick | Inadequate Procedure for RWCU Backwashing Operations | A self-revealing Green NCV of Technical Specification (TS) 6.8.1.a, Procedures and Programs, occurred because Exelon failed to establish, implement, and maintain an adequate procedure for the control of radioactivity and limiting personnel exposure during operation of a solid radioactive waste system. Specifically, the procedure for the conduct of reactor water cleanup (RWCU) filter media backwashing and collection was inadequate to ensure a sufficient receiving tank volume prior to transferring waste media. On June 28, 2015, this resulted in the overflow of a Unit 2 RWCU collection tank and back up of the reactor building floor drain system, causing high levels of radioactive contamination in accessible portions of the Unit 2 reactor building, and resulting in radioactive contamination of personnel. Exelon controlled access, decontaminated affected areas and personnel, conducted bounding dose assessments, performed extent of condition reviews, and revised affected procedures to address the issue. Exelon placed this issue into the corrective action program as issue report (IR) 2520732. This issue is more-than-minor because if left uncorrected, it had the potential to lead to a more significant safety concern. Specifically, the failure to effectively control and manage radioactive material could result in significant unplanned, unintended occupational radiation exposure of workers. Using IMC 0609, Appendix C, Occupational Radiation Safety Significance Determination Process, the inspectors determined that this finding was of very low safety significance (Green) because the finding did not involve an as low as is reasonable achievable (ALARA) issue, was not an overexposure, did not result in a substantial potential for an overexposure, and did not compromise the ability to assess dose. The inspectors determined this finding has a cross-cutting aspect in the area of Human Performance, Avoiding Complacency, because Exelon did not recognize and plan for the possibility of mistakes, latent issues, and inherent risk, even while expecting successful outcomes, and therefore did not implement appropriate error reduction tools. Specifically, Exelon operated the backwash receiving tank (BWRT) to routinely accept high level alarms with associated potential for system overflow. Consequently, although this mode of operation of the system was longstanding, the issue reflects present performance. |
| 05000272/FIN-2015008-02 | 2015Q2 | Salem | Failure to Correct a Condition Adverse to the Quality of the Chillers | The inspectors identified a Green NCV of 10 CFR, Part 50, Appendix B, Criterion XVI, because PSEG did not assure that an identified condition adverse to quality was corrected. The condition adverse to quality was associated with improper maintenance of the 12 chiller which led to the chiller failure on August 23, 2014. Specifically, a procedure related to compressor rebuilds was not effectively updated to address the improper maintenance practice. PSEG entered this violation into the CAP as notification 20690927, has placed compressor rebuilds that would require use of this procedure on hold, and has purchased new compressors for contingent replacement pending completion of the compressor maintenance procedure changes. The inspectors determined this performance deficiency was more than minor because it was associated with the procedure quality attribute of the Mitigating System cornerstone, and adversely affected the cornerstone objective of ensuring the reliability of systems that respond to initiating events to prevent undesirable consequences. Specifically, improper torqueing of the No. 4 discharge valve plate bolts for the 12 chiller caused the trip of that chiller on August 23, 2014, and, absent the procedural change, the vulnerability continued to exist for the occurrence of future improper torqueing and subsequent chiller failure. The inspectors determined that this finding screened to Green in accordance with IMC 0609, Appendix A, because the finding did not represent an actual loss of function of at least a single train for greater than its technical specification allowed outage time. The inspectors determined that this finding had a cross-cutting aspect in evaluation, because PSEG Root Cause 70169007 did not identify the improper torqueing of the discharge plate bolts as a condition adverse to quality. Consequently, PSEG assigned an action (ACIT) to address the problem, rather than a corrective action (CA) which, per LS-AA-125, requires additional reviews that verify the quality of completed corrective actions before closure. |
| 05000272/FIN-2015008-03 | 2015Q2 | Salem | Licensee-Identified Violation | 10 CFR Part 50, Appendix B, Criterion XVI requires, in part, that measures shall be established to assure that conditions adverse to quality are promptly identified and corrected. Contrary to the above, PSEG did not establish measures to assure that a condition adverse to the quality related to safety-related chillers was promptly corrected. Specifically, PSEG determined that previous corrective actions for chiller operating temperature setpoint overlap, which were directed in several previous CAP evaluations that were completed between 2009 and 2013, were not implemented in a timely manner. This caused excessive chiller cycling and load sharing and prolonged and cyclic operation at low load conditions, which caused component fatigue and compressor damage. In response to this issue, PSEG completed a root cause evaluation and established corrective actions to develop and install a chiller operating setpoint design change package. The inspectors determined that this finding screened to Green in accordance with IMC 0609, Appendix A, because the finding did not represent an actual loss of function of at least a single train for greater than its technical specification allowed outage time. This issue is tracked in the corrective action program under RCE 70169007. |
| 05000289/FIN-2014009-01 | 2014Q2 | Three Mile Island | Inadequate Corrective Actions for a Condition Adverse to Quality that Caused the Failure of Two Primary Containment Isolation Valves | The inspectors identified a finding of very low safety significance involving an NCV of Title 10 of the Code of Federal Regulations (10 CFR) 50, Appendix B, Criterion XVI, Corrective Action, because Exelon did not take adequate corrective actions to address a condition adverse to quality that caused the failure of two primary containment isolation valves. Specifically, the corrective actions implemented after the failure of CA-V-13 in 2010 and WDL-V- 303 in 2013 did not ensure that the deficient basic work practices that resulted in the valve failures were corrected. Exelon documented this issue in the corrective action program as issue report (IR) 1664529 and took prompt actions to validate the operability of valves with similar actuators that had been worked since refueling outage T1R19. In addition, Exelon is performing a cause evaluation to fully understand the causes of the issue and implement actions to correct the condition adverse to quality prior to the next valve maintenance window. The finding is associated with the Barrier Integrity cornerstone and is more than minor because if left uncorrected it could lead to a more significant safety concern. Specifically, the uncorrected deficient basic work practices could result in additional primary containment isolation valve failures. In accordance with IMC 0609.04, Initial Characterization of Findings, and Exhibit 3 of IMC 0609, Appendix A, The Significance Determination Process for Findings At-Power, issued June 19, 2012, the inspectors determined that the finding was of very low safety significance (Green) because it does not represent an actual open pathway in the containment and did not impact the hydrogen igniters. The finding has a cross-cutting aspect of evaluation in the problem identification and resolution area because Exelon did not thoroughly evaluate the condition to ensure that corrective actions addressed the cause. Specifically, Exelon identified that deficient basic work practices during valve actuator reassembly were the probable cause of the WDL-V-303 failure in 2013 and had been previously identified as the cause of the CA-V-13 failure in 2010, but Exelon did not evaluate the effectiveness of the corrective actions completed after the CA-V-13 failure or the need for additional corrective actions to address the probable cause. |
| 05000272/FIN-2011009-01 | 2011Q3 | Salem | Untimely Completion of Corrective Actions Results in No. 11 Service Water Strainer Trip Due To Grassing | The inspectors identified a self-revealing apparent violation of 10 CFR 50, Appendix B, Criterion XVI, Corrective AGtion, because the 11 service water strainer overloads tripped on February 9, 2011, due to binding of the strainer rotating drum, which rendered the 11 service water strainer pump inoperable and unavailable. The binding occurred because PSEG did not complete timely corrective actions for a condition adverse to quality identified following an April 4,2010, 11 service water strainer trip. Specifically, PSEG did not repair excessive grooves identified on the 11 service water strainer body wear surface by taking the actions specified in their corrective action program in January 2011. As a result, the grooves caused river grass to become trapped between the rotating strainer drum and the body wear surface, which eventually bound and tripped the strainer overloads. As corrective action, before the next spring grassing season, PSEG will temporarily fill in the grooves on the 11 service water strainer body wear surface and then trend the body wear ring condition for future replacement with a monel wear ring. PSEG entered this issue into the corrective action program as 20523166. This performance deficiency was more than minor because it was associated with the equipment performance attribute of the initiating events and mitigating systems cornerstones. The finding affected the cornerstones\\\' objectives to limit the likelihood of those events that could upset plant stability and challenge critical safety functions during power operations and to ensure the availability and reliability of systems that respond to initiating events to prevent undesirable consequences. Specifically, not promptly correcting the excessive grooving identified on that strainer\\\'s body wear ring degraded the availability and reliability of the 11 service water train. The significance of this finding is designated as To Be Determined (TBD) until a regional senior reactor analyst completes a Phase 3 analysis, in accordance with IMC 0609, Appendix A, Determining the Significance of Reactor Inspection Findings for At-Power Situations (IMC 0609A). Phase 1 screened the finding to Phase 2 because the inspectors concluded that the finding contributed to both the likelihood of a reactor trip and the likelihood that mitigating systems would not have been available. This conclusion was based upon the increased chance of a loss of service water given one train being removed for strainer repairs and the loss of redundancy in the service water system to cool mitigating equipment over the assumed 53 hour exposure period. The Phase 3 analysis was required because the Salem Pre-solved Risk-Informed Inspection Notebook does not address the loss of one train of service water. This finding has a cross-cutting aspect in the area of problem identification and resolution, corrective action program, because PSEG did not take appropriate corrective actions to address a safety issue in a timely manner, commensurate with the safety-significance and complexity (P.1(d)). Specifically, PSEG did not implement timely actions to repair excessive grooves identified in the 11 service water strainer body wear ring in January 2011 because work control documents were not correctly coded in July 2010. |
| 05000272/FIN-2011009-02 | 2011Q3 | Salem | Biennial PI&R Summary Assessment | The inspectors concluded that PSEG was generally effective in identifying, evaluating, and resolving problems. PSEG personnel identified problems, entered them into the corrective action program at a low threshold, and prioritized issues commensurate with their safety significance. In most cases, PSEG appropriately screened issues for operability and reportability, and performed causal analyses that appropriately considered extent of condition and cause, generic issues, and previous occurrences. The inspectors also determined that PSEG typically implemented corrective actions to address identified problems in a timely manner. However, for one issue reviewed by the inspectors, the corrective actions completed by PSEG were not timely and the inspectors determined that this was a violation of NRC requirements, in the area of corrective action implementation. The inspectors concluded that, in general, PSEG adequately identified, reviewed, and applied relevant industry operating experience to Salem operations and identified appropriate corrective actions. In addition, based on those items selected for review, the inspectors determined that PSEG self-assessments and audits were thorough and appropriately used the corrective action program to initiate corrective actions for identified issues. With respect to safety conscious work environment, based on interviews and reviews of the corrective action program and the employees concerns program (ECP) the inspectors did not identify conditions that negatively impacted the site\\\'s safety conscious work environment and determined that site personnel were willing to raise safety issues through multiple means. |
| 05000318/FIN-2010006-02 | 2010Q2 | Calvert Cliffs | Inadequate Preventive Maintenance Results in the Failure of the 2B Emergency Diesel Generator | The NRC identified an apparent violation of Technical Specification5.4.1 for the failure of Constellation to establish, implement, and maintain preventive maintenance requirements associated with safety related relays. The team identified that Constellation did not implement a performance monitoring program specified by the licensee in Engineering Service Package (ES2001 00067) in lieu of a previously established (in 1987) 1 O-year service life replacement PM requirement for the 2B EDGT3A time delay relay. As a consequence, the 2B EDG failed to run following a demand start signal on February 18, 2010. Following identification of the failed T3A relay, it was replaced and the 2B EDG was satisfactorily tested and returned to service. In addition, time delay relays used in the 1 Band 2A EDG protective circuits, that also exceeded the vendor recommended 1 O-year service life, were replaced. Constellation entered this issue, including the evaluation of extent-of-condition, into the corrective action program. This finding is more than minor because it is associated with the equipment performance attribute of the Mitigating Systems Cornerstone and adversely impacted the objective of ensuring the availability, reliability, and capability of the safety related 2B EDG to respond to a loss of normal electrical power to its associated safety bus. This finding was assessed using IMC 0609, Appendix A and preliminarily determined to be White (low to moderate safety significance) based upon a Phase 3 Risk Analysis with an exposure time of 323 days which resulted in a total (internal and external contributions)calculated conditional core damage frequency (CCDF) of 7.1 E-6. The cause of this finding is related to the crosscutting area of Human Performance, Resources aspect H.2(a) because preventive maintenance procedures for the EDGs were not properly established and implemented to maintain long term plant safety by maintenance of design margins and minimization of long standing equipment issues. |
| 05000277/FIN-2009008-01 | 2009Q3 | Peach Bottom | Failure to Take Adequate Cas for Grease Applied to DC Contactors | 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 |
| 05000220/FIN-2007004-03 | 2007Q3 | Nine Mile Point | Licensee-Identified Violation | 10 CFR Part 50.65(a)(4) requires that, before performing maintenance activities (including but not limited to surveillance, post-maintenance testing, and corrective and preventive maintenance), the licensee shall assess and manage the increase in risk that may result from the proposed maintenance activities. Contrary to the above, on September 24, 2007, NMPNS did not assess and manage the increase in risk that resulted from performing surveillance on the 102 EDG concurrent with maintenance on the Unit 1 diesel fire pump. In accordance with IMC 0609, Appendix K, \\\"Maintenance Risk Assessment and Risk Management Significance Determination Process,\\\" the inspectors determined the finding to be of very low safety significance due to the short time period in which the EDG was unavailable. This event is documented in NMPNS corrective action program as CR 2007-5627 |