05000335/FIN-2009006-04
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Description | The team identified a URI related to the licensees failure to provide adequate procedures for restoration of non-essential CCW following a SIAS. Specifically, emergency operating procedure, 1-EOP-99, Appendix A, Sampling Steam Generators, and Appendix J, Restoration of CCW and CBO to the RCPs, Rev. 38, did not address the potential adverse impact on essential cooling flow required to mitigate a LOCA when the non-essential CCW was restored. Emergency Operating Procedure 1-EOP-99, Appendix A and J, step 2, directed the operator to restore non-essential CCW if the related isolation valve closed due to the SIAS. Additionally, an input to isolate non-essential CCW was provided by a low CCW surge tank level signal. The purpose of both signals was to assure adequate cooling flow was provided to essential loads for design basis accident conditions. The station CCW flow balance procedure (1-NOP-14.02, Rev. 20, Appendix I) positioned system flow balance valves to establish cooling flow to the essential components based on assumptions in the LOCA Containment Analysis, JPN-PSL-SENP-93-001, Rev. 0. When establishing the essential cooling flow balance per this procedure, the nonessential portion of the CCW system was isolated. Therefore, adequate essential cooling flow was assured only when the non-essential portion of the system was isolated. The EOP assured that CCW train separation was maintained when the nonessential header was restored but did not address that the essential cooling load flow would be diverted with the potential adverse impact on cooling capability for the essential components, primarily the containment coolers used in containment pressure control, the shutdown heat exchanger used for decay heat removal, and cooling for emergency core cooling system (ECCS) pumps. The team concluded that the procedure action to restore non-essential CCW flow after an SIAS signal adversely impacted the licensees capability to assure adequate cooling of essential components following a LOCA induced SIAS. In particular, this concern applied to the circumstance of only one train of CCW being available during LOCA, assuming a single failure event resulted in the loss of the redundant train. Following identification by the team, the licensee initiated CR 2009-22623 to assess this issue. The immediate compensatory action was to issue a standing order to the operators related to Emergency Operating Procedure 1, 2-EOP-99 directing them to not restore the non-essential CCW when responding to a SIAS when only one CCW train was available. Additionally, the licensee initiated an evaluation to assess the impact on essential CCW flow if non-essential CCW was restored to allow cooling of the RCPs and the steam generator sample coolers. The licensees failure to provide adequate procedures for restoration of non-essential CCW following a SIAS was identified as a performance deficiency. The licensees evaluation, and the NRC review of this evaluation, is needed to determine if adequate cooling would be available to essential equipment following the LOCA induced SIAS when the non-essential CCW was restored. This issue is being documented as URI 05000335, 389/2009006-04, Inadequate Procedure for Restoration of Non-Essential CCW Flow Following a SIAS |
Site: | Saint Lucie ![]() |
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Report | IR 05000335/2009006 Section 1R21 |
Date counted | Sep 30, 2009 (2009Q3) |
Type: | URI: |
cornerstone | Mitigating Systems |
Identified by: | NRC identified |
Inspection Procedure: | IP 71111.21 |
Inspectors (proximate) | R Taylor G Kuzo T Hoeg S Sanchez D Rich M Coursey R Patterson A Sengupta W Deschaine C Dykesb Desaij Hamman M Shylamberg N Greca R Moore R Taylor S Rose |
INPO aspect | |
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Finding - Saint Lucie - IR 05000335/2009006 | |||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
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Finding List (Saint Lucie) @ 2009Q3
Self-Identified List (Saint Lucie)
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