05000456/FIN-2013003-03
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Finding | |
|---|---|
| Title | Implications of Control Room Ventilation Monthly Surveillance |
| Description | The inspectors identified an Unresolved Item (URI) regarding the use of TS Limiting Condition for Operation (LCO) 3.7.10 during the monthly control room ventilation system surveillance. Specifically, the inspectors questioned whether a step in procedure 0BwOSR 3.7.10.1-1, Control Room Ventilation Filtration Surveillance (Train A), to realign the VC suction source, and which appeared to defeat an automatic engineered safety feature (ESF) realignment, impacted the filtration system (Condition A) or control room envelope (CRE) boundary (Condition B) of the LCO. At 4:05 p.m. on May 8, 2013, the licensee commenced a routine monthly surveillance of the A VC filtration train using procedure 0BwOSR 3.7.10.1-1, Control Room Ventilation Filtration Surveillance (Train A). During performance of the surveillance, at 7:09 p.m., the licensee noted that B VC train damper 0VC08Y was unexpectedly open when it should have been closed. Approximately 25 minutes later, the damper repositioned closed. Operators were dispatched to inspect the damper and heard an abnormal grinding noise coming from the hydramotor. Consultation with the system engineer indicated that the grinding noise was likely caused by a degraded bearing. As a result, the licensee declared the B train of VC inoperable and entered LCO 3.7.10, Condition A, One VC Filtration System Train Inoperable for Reasons Other Than Condition B. Condition B stated, One or More VC Filtration System Trains Inoperable Due to Inoperable CRE Boundary in Mode 1, 2, 3, or 4. The licensee elected to continue with the routine surveillance on the A VC train. Step F5.1 of procedure 0BwOSR 3.7.10.1-1 directed Operations to enter LCO 3.7.10, Condition A, for the A VC train while the makeup filter selector switch was repositioned from auto to outside air then turbine building and back to auto as part of a contact check. The licensee entered LCO 3.7.10, Condition A, for the A VC train at 4:33 a.m. on May 9, 2013, and exited that Condition at 4:35 a.m. For those 2 minutes, both Units also entered LCO 3.0.3, since the A and B VC trains were simultaneously inoperable due to LCO 3.7.10, Condition A. During plant status activities on the morning of May 9, 2013, the inspectors noted discussions among senior plant personnel about whether LCO 3.7.10, Condition B (not Condition A) was actually the correct Condition to be entered while performing Step F5.1 of procedure 0BwOSR 3.7.10.1-1. The inspectors reviewed the TSs and discussed the system design with the VC system engineer. The VC system is designed such that when the makeup air suction is from outside air, the system would automatically realign the source air to the turbine building upon an air intake high radiation signal or a safety injection signal. When the makeup filter selector switch is not in the auto position, this automatic realignment will not occur, and manual actions would be required for the system to perform its ESF function. Additionally, the inspectors reviewed the licensees Control Room Habitability Program (CRHP), which included the following definitions: CONTROL ROOM ENVELOPE (CRE) BOUNDARY: A combination of walls, floor, roof, ducting, doors, penetrations, and equipment that physically form the CRE. CONTROL ROOM HABITABILITY SYSTEMS (CRHS): The plant systems that help ensure CRE habitability. This includes the Control Room emergency ventilation/filtration system and the Control Room HVAC systems. The CRE boundary is considered as an integral part of the CRHS, since it is critical to maintaining CRE habitability. The inspectors view was that the automatic realignment feature of the A VC train, which was blocked at the time the switch was not in auto, did not constitute part of the CRE boundary as defined in the CRHP. In addition, manual actions were required for the safety-related system to perform its ESF design function. As a result, the inspectors communicated to licensee management their view that Condition A was the correct Technical Specification Action Statement (TSAS) to be entered when performing the surveillance. Following this discussion, the licensee continued to believe that Condition B was the correct TSAS to enter when performing this surveillance. The inspectors also communicated their concerns that main control room logs, as officially recorded, did not completely and accurately capture the events that occurred on the night shift from May 8 to May 9, 2013. During plant status activities on May 9, the inspectors reviewed the main control room operating logs at approximately 6:30 a.m., and noted the log entries for entering LCO 3.7.10, Condition A, for the 0A VC train, and LCO 3.0.3, at 4:33 a.m. and exiting those LCOs at 4:35 a.m. However, later that morning when the logs were reviewed again, the inspectors noted those log entries had been revised. The log entries were annotated with, Late Entry 1030 5/9/13, and referenced entry into LCO 3.7.10, Condition B, and made no mention of LCO 3.0.3. There was no indication that anything had been revised or that LCO 3.0.3 had been entered. As a result of the inspectors concerns, the licensee generated IR 1519660, Lack of Detail in Log Entries, on May 30, 2013. Additionally, an Operations Noteworthy Event briefing sheet was created on June 12, 2013, and discussed with all Operating crews. The Noteworthy Event briefing sheet included the statement, Initially, LCO 3.0.3 was entered, but was retracted on days. LCO 3.7.10, Condition B, was determined to be the correct LCO entry. On July 8, 2013, the licensee again performed the monthly VC surveillance. Upon review of the main control room logs, the inspectors noted that LCO 3.7.10, Condition A, had been entered from 11:14 a.m. to 11:33 a.m. while alternating the suction source between outside and turbine building air. When questioned why the Noteworthy Event briefing sheet instructed Operating crews to enter Condition B and yet the crews entered Condition A, the licensee stated they were waiting for a more comprehensive review of the issue before revising the surveillance procedure. At the end of the inspection period, the inspectors were in the process of discussing the issue with NRC staff in the Office of NRR, reviewing the licensees determination of LCO applicability, and reviewing control room ventilation system design documentation. Pending additional information from the NRR staff, a complete understanding of the licensees position, and a more detailed understanding of the VC system design, this issue is considered a URI. (URI 05000456/2013003-03; 05000457/2013003-03, Implications of Control Room Ventilation Monthly Surveillance) |
| Site: | Braidwood  |
|---|---|
| Report | IR 05000456/2013003 Section 1R22 |
| Date counted | Jun 30, 2013 (2013Q2) |
| Type: | URI: |
| cornerstone | Emergency Prep |
| Identified by: | NRC identified |
| Inspection Procedure: | IP 71111.22 |
| Inspectors (proximate) | A Garmoe E Duncan J Benjamin J Corujo Sandin J Laughlin J Neurauter J Steffes M Perry N Feliz Adorno R Ng T Gom Learnm Perry N Feliz Adorno R Edwards R Ng T Daun T Go V Meghani A Dahbur A Dunlop A Garmoe A Sallman E Duncan J Benjamin J Neurauter J Robbins |
| INPO aspect | |
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Finding - Braidwood - IR 05000456/2013003 | |||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
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Finding List (Braidwood) @ 2013Q2
Self-Identified List (Braidwood)
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