IR 05000335/2014009
| ML14300A013 | |
| Person / Time | |
|---|---|
| Site: | Saint Lucie  |
| Issue date: | 10/23/2014 |
| From: | Jensen J Florida Power & Light Co |
| To: | Document Control Desk, Office of Nuclear Reactor Regulation |
| References | |
| EA-14-131, IR 2014009, L-2014-323 | |
| Download: ML14300A013 (3) | |
Text
October 23, 2014
L-2014-32310 CFR 2.201U. S. Nuclear Regulatory CommissionAttn: Document Control DeskWashington, DC 20555Re: St. Lucie Units. I and 2Docket Nos. 50-335 and 50-389Response to Preliminary White Finding in NRC Inspection Report05000335/2014009 and 05000389/2014009; EA-14-131Reference:1. NRC Letter from Joel T. Munday to Mano Nazar dated September 24, 2014,"St. Lucie Plant -NRC Inspection Report 05000335/2014009 and05000389/2014009; Preliminary White Finding and Apparent Violations."ADAMS accession number ML 1 4267A337.On September 24, 2014, Florida Power & Light (FPL) received the NRC Inspection Report (Reference1) describing a preliminary white finding associated with a water intrusion event at the St. Lucie Planton January 9, 2014. Reference I provided FPL an option of responding to the preliminary whitefinding within 30 days. This letter provides FPL's response.FPL concurs with the categorization and basis for the finding. FPL recognizes that there wereprevious opportunities to identify the degraded flood protection features and fully comprehends thesignificance associated with the actual rain event and other postulated precipitation events. Follow-upinspections were performed and all discrepancies were promptly addressed. Additionally, a root causeevaluation (RCE) was performed that identified opportunities for additional corrective actions.As discussed in Reference 1, the degraded conduits have been sealed and the condition no longerexists. The causal factors associated with this event are known and corrective actions wereestablished to prevent recurrence. FPL continues to pursue completion of corrective actions toimprove flood mitigation margin. The attachment to this letter summarizes the important insightsgained from our significance determination review and RCE.Please contact Eric Katzman, St. Lucie Licensing Manager, at (772) 467-7734 if there are anyquestions regarding this response.
Sincerely,Joseph JensenSite Vice PresidentSt. Lucie Nuclear PlantJJ/rcsAttachmentcc: NRC Region 11 AdministratorSt. Lucie Plant NRC Senior Resident InspectorFlorida Power & Ught CompanyAbei6501 S. Ocean Drive, Jensen Beach, FIL 34957 L-2014-323AttachmentPage 1 of 2L-2014-323 Attachment30-Day Written Response to Preliminary White Finding L-2014-323AttachmentPage 2 of 2Safety Si2nificance DeterminationThe Internal Events Model was used to evaluate the risk associated with the potential loss ofthe high pressure safety injection (HSPI) pumps, the low pressure safety injection (LPSI)pumps and the charging pumps as a result of postulated flooding of the emergency corecooling system rooms. Based on FPL's analysis, the calculated overall significance wasidentified as low to moderate, consistent with the NRC assessment.RCE InsightsThe RCE identified that a legacy plant modification installed conduit penetrations in thereactor auxiliary building (RAB) below the flood level without flood barrier seals. Themodification did not follow the requirements of ANSI N45.2.1 1, Requirements and Guidancefor a Quality Assurance Program for the design of nuclear power plants Systems, Structuresand Components (SSCs) that affect the final design of the plant. This created a latent designweakness that went undetected until the rain event of January 9, 2014.Additionally, the station had several opportunities to identify the open penetrations but did notidentify and correct the missing barriers. Previous inspections did identify the degradedconduits, however; the evaluations focused on the condition of the non-safety related cablingin the degraded conduits and did not consider flooding hazards.Corrective Actions Completed* Implemented permanent flood seal design and repair for the subject conduits," Revised flood response procedures to improve mitigation of internal and externalflooding,* Re-performed the Fukushima walkdowns incorporating lessons learned from the rootcause evaluation and submitted Revision I to the Fukushima walkdown report,FPL060-PR-001, per L-2014-297 on 9/26/14, and* Restored and improved internal and external flood barrier integrity identified as part ofthe extensive extent of condition review for Unit 1 and 2.Corrective Actions in Pro2ress:St. Lucie is in the process of completing several additional corrective actions. These include:* Revising the St. Lucie procedure for plant barrier control to strengthen the focus onexternal flooding," Updating plant drawings to identify all the flood barrier seals," Developing preventative maintenance for flood seals and other equipment importantfor flood mitigation, and* Performing extensive upgrades to the site storm drainage system and purchasing ofadditional high capacity water removal equipment.