05000389/FIN-2014005-01
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Finding | |
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| Title | Failure to Follow Work Instructions during Installation of Unit 2 Vent Valve V3811 |
| Description | The licensee identified a finding of very low safety significance (Green) and associated NCV of 10 CFR Part 50, Appendix B, Criterion V, Instructions, Procedures, and Drawings, which requires, in part, that activities affecting quality shall be accomplished in accordance with instructions, procedures, and drawings. During the performance of WO 40118062, on breaker B52DB50078, the licensee failed to correctly perform the steps in section 5.4.5 of procedure RMP 9303, DB50 Breaker Routine Maintenance. Procedure RMP 9303 inspected and bent as necessary, the control relay contacts for the breaker to obtain the proper contact alignment. The breaker was subsequently installed and used in the P32C SW pump breaker cubicle, 1B5220C, and failed to close on May 29, 2014, during surveillance testing. The licensee concluded that oxide buildup on the control relay contacts had prevented them from making up, which prevented the breaker from closing. The oxide buildup was the result of improper contact alignment, which inhibited the proper wiping action needed to clean the contacts each time they were cycled. The licensee concluded, based on the contact arms being rigid, that the misalignment was present since the new control relay was installed and RMP 9303 performed in July 2012. Title 10 CFR Part 50, Appendix B, Criterion V, requires, in part, that activities affecting quality shall be accomplished in accordance with instructions, procedures, and drawings. RMP 9303 is the licensees procedure containing instructions for the inspection and adjustment of safety-related control relay contacts, an activity affecting quality. Contrary to the above, between July 11, 2012 and July 24, 2012, the licensee failed to properly complete RMP 9303 Section 5.4.5, which required the licensee to inspect and adjust contacts to ensure that the contacts had the appropriate gap, contacted in the appropriate sequence, and contacted in the approximate center. The inspectors determined that this issue was more than minor as it impacted the equipment performance attribute of the Mitigation Systems Cornerstone. The inspectors determined the finding could be evaluated using the SDP in accordance with IMC 0609, Significance Determination Process, Attachment 0609.04, Initial Characterization of Findings, dated June 19, 2012, and Appendix A, The Significance Determination Process for Findings At-Power, Exhibit 2, Mitigating Systems Screening Questions, dated June 19, 2012. Since the breaker operated successfully on May 7 and failed to operate on May 29, the inspectors answered "Yes" to the mitigating systems screening question number 3, and consulted regional senior risk analysts to perform a detailed risk evaluation. The senior risk analysts performed a detailed risk evaluation for the finding as described below. Since the time of actual failure of the breaker for the P32C SW pump cannot be determined, a T/2 evaluation provides an exposure time of 11 days (i.e., 22 days from May 7, 2014 to May 29, 2014 divided by 2 or 11 days). The T/2 exposure time is appropriate based on Risk Assessment Standardization Project manual guidance. The Point Beach Standardized Plant Analysis Risk model version 8.22, Systems Analysis Programs for Hands-on Integrated Reliability Evaluations (SAPHIRE) version 8.1.2 software, and the Support System Initiating Event (SSIE) methodology that is incorporated into the Standardized Plant Analysis Risk model was used to obtain a CDF of 1.29E7/yr for internal events for the failure-to-start of the P32C SW pump due to the breaker failure. The dominant core damage sequences involve a loss-of-offsite-power (LOOP) with the failure of AFW and the failure of high pressure recirculation. Since the total estimated change in core damage frequency was greater than 1.0E7/yr, an evaluation was performed for external event delta risk contributions. The total CDF was found to be the sum of the CDF contributions from internal events, fire, and seismic or 4.46E7/yr [i.e., 1.29E7/yr + 3.21E7/yr + 8.4E11/yr = 4.50E7/yr]. Large Early Release Frequency - Since the total estimated change in core damage frequency was greater than 1.0E7/yr, IMC 0609 Appendix H, Containment Integrity Significance Determination Process was used to determine the potential risk contribution due to large early release frequency. Each Point Beach Unit is a 2-loop Westinghouse Pressurized Water Reactor with a large dry containment. Sequences important to large early release frequency include steam generator tube rupture events and inter-system loss-of-coolant-accident events. These were not the dominant core damage sequences for this finding. Based on the Detailed Risk Evaluation, the inspectors determined that the finding was of very low safety-significance (Green). This issue was entered into the CAP as AR 01968602 and AR 02020073. |
| Site: | Saint Lucie  |
|---|---|
| Report | IR 05000389/2014005 Section 4OA2 |
| Date counted | Dec 31, 2014 (2014Q4) |
| Type: | NCV: Green |
| cornerstone | Mitigating Systems |
| Identified by: | Self-revealing |
| Inspection Procedure: | IP 71152 |
| Inspectors (proximate) | J Reyes J Rivera-Ortiz M Riches P Capehart S Sandal T Morrissey |
| Violation of: | 10 CFR 50 Appendix B Criterion V |
| CCA | H.8, Procedure Adherence |
| INPO aspect | WP.4 |
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Finding - Saint Lucie - IR 05000389/2014005 | |||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
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Finding List (Saint Lucie) @ 2014Q4
Self-Identified List (Saint Lucie)
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