05000272/FIN-2015008-01
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Finding | |
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| Title | Inadequate Maintenance Rule System Performance Criteria Selection |
| Description | The inspectors identified a URI associated with inadequate Maintenance Rule Performance Criteria selection. Specifically, the inspectors determined that PSEG did not follow station procedures to: 1) determine that the number of maintenance preventable functional failures (MPFF) allowed per 10 CFR 50.65(a)(3) evaluation period was consistent with the assumptions in the probabilistic risk assessment (PRA); and 2) review and approve reliability performance criteria (PC) that was higher than the number of PRA-supplied basic event failures. The inspectors determined that additional information was needed to determine if these performance deficiencies were more than minor. The inspectors performed a review of PSEGs Focused Area Self-Assessment (FASA) of the Maintenance Rule (MRule) Program, completed August 30, 2014, to determine if PSEG was appropriately assessing MRule program performance in accordance with LS-AA-126-1001, Self-Assessments. The purpose of PSEGs FASA was to ensure the MRule Program was implemented in accordance with 10 CFR 50.65, as well as PSEG program procedures. The inspectors noted that the MRule Program FASA met the requirements of LS-AA-126-1001, was sufficiently critical, identified several deficiencies that were entered into the CAP, and resulted in multiple recommendations. As a result of the FASA, PSEG determined that multiple structures, systems, and components (SSCs) in (a)(2) status had to be re-evaluated for (a)(1) status, due to those SSCs having had their Functional Failure Cause Determinations (FFCDE) and unavailability (UA) amounts incorrectly assessed in the past. The inspectors reviewed the list of systems re-evaluated for (a)(1) status due to the FASA, as well as a listing of systems that remained in (a)(2) status and actual SSC performance data against the PC established under ER-AA-310-1003, Maintenance Rule Performance Criteria Selection. During this review the inspectors noted approximately 25 high safety significant systems (HSS) with reliability PC greater than two maintenance preventable functional failures (MPFFs). According to ER-AA-310-1003, Attachment 3, flowchart Process for Selecting Reliability Performance Criteria, HSS SSCs, with reliability PC greater than or equal to two MPFFs require SSC past performance documentation. Additionally, Attachment 1, steps 2.B.3 and 2.B.4, state that for HSS SSCs with high risk achievement worth (RAW) values, a reliability PC greater than or equal to zero or one MPFF requires SSC past performance documentation. The inspectors requested that PSEG provide past performance documentation for the HSS SSCs with reliability PC greater than two MPFFs. PSEG provided documentation of HSS SSC PC approval from 1997, when the MRule Program was first implemented by PSEG. The inspectors determined this documentation did not support the assigned PC, because it did not consider the last 18 years of SSC past performance. The inspectors also reviewed ER-AA-310-1007, Maintenance Rule Periodic (a)(3) Assessment. Step 5.11.1.4 states Determine that the number of MPFFs allowed per evaluation period is consistent with the assumptions in the PRA. Contrary to ER-AA-310-1007, step 5.11.4, the last two periodic (a)(3) assessments performed by PSEG: April 1, 2011 through September 9, 2012; and October 1, 2012 through June 30, 2014; did not verify that the number of MPFFs allowed per evaluation period was consistent with the assumptions in the PRA. Additionally, ER-AA-310-1003, step 4.3.2, states, in part, that Unless justified and approved by the Maintenance Rule Expert Panel, the number of MPFFs selected, as a Reliability PC, may not be higher than the PRA-supplied number of Functional Failures (FFs). The inspectors then reviewed SC-MRULE-002, Maintenance Rule Performance Criteria Verification Following Salem SA112A PRA Update, subsequent to the most recent update performed in October 2014. The inspectors noted that to complete this verification, PSEG requantified the PRA model by changing the failure probabilities of the basic events to reflect the MRule PC. The result was a 98% increase in the Salem base core damage frequency (CDF) of 1.55E-05. The inspectors determined that this data was reflective of SSC reliability PC above the PRA-supplied number of basic event failures. As such, contrary to ER-AA-310-1003, step 4.3.2, the number of MPFFs selected as reliability PC was higher than the PRA-supplied number of FFs, and, based on the lack of documentation supplied by PSEG, the inspectors concluded this was not justified or approved by Maintenance Rule Expert Panel. The inspectors determined that the failure to meet ER-AA-310-1007, step 5.11.4, and ER-AA-310-1003, step 4.3.2, was a performance deficiency. However, at the time of inspection, the inspectors did not have the information needed to determine the consequence of the performance deficiency. Information was needed to determine whether the performance deficiency was more than minor. Specifically, PSEG did not provide SSC past performance documentation for HSS SSCs with reliability PC greater than the PRA-supplied number of basic event failures in accordance with ER-AA-310-1003 Attachment 1 and 3. The inspectors will use this information to determine whether the performance or condition of HSS SSCs was effectively controlled through the performance of appropriate preventive maintenance under 10 CFR 50.65(a)(2), and also to determine if those HSS SSCs being monitored under 10 CFR 50.65(a)(1) were assigned appropriate goals and monitoring when considered against the appropriate reliability PC threshold. This issue was determined to be a URI IAW Inspector Manual Chapter (IMC) 0612. |
| Site: | Salem  |
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| Report | IR 05000272/2015008 Section 4OA2 |
| Date counted | Jun 30, 2015 (2015Q2) |
| Type: | URI: |
| cornerstone | Mitigating Systems |
| Identified by: | NRC identified |
| Inspection Procedure: | IP 71152 |
| Inspectors (proximate) | A Ziedonis D Orr E Burket F Bower G Dipaolo J Kulp J Poehler M Draxton M Modes P Finney R Nimitz R Vadella T O'Haraa Ziedonisb Lin G Dentel L Clinea Ziedonisd Orr E Burket F Bower G Dipaolo J Kulp M Draxton M Modes P Finney R Nimitz R Vadella T O'Hara |
| INPO aspect | |
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Finding - Salem - IR 05000272/2015008 | |||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
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Finding List (Salem) @ 2015Q2
Self-Identified List (Salem)
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