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At 17:35 hours on June 19, 2008, the Contr … At 17:35 hours on June 19, 2008, the Control Room authorized post maintenance testing following replacement of solenoid valves affecting the 2B Control Room Emergency Ventilation (CREV) subsystem. This testing was required to restore this Subsystem to OPERABLE following maintenance. This test inputs a Simulated high radiation signal into the logic for Control Building HVAC system and ensures that the Control Room Emergency Ventilation subsystem automatically aligns to the Radiation/Smoke Protection mode. During performance of this test, the Control Building Exhaust Fan Damper (2D) failed to close and the associated Control Building Exhaust Fan failed to trip as expected. These functions are required to occur to maintain a positive pressure in the Control Building during a high radiation in the Control Building ventilation intake plenum or during smoke intrusion into the Control Building. Since Brunswick has a shared control room, Unit 1 and Unit 2 entered Technical Specification (TS) 3.7.3,'Control Room Emergency Ventilation (CREV) System,' Required Action B.1 (i.e., be in Mode 3 within 12 hours).</br>At 1910, the 2A Control Room Emergency Ventilation (CREV) subsystem was manually placed in the Radiation/Smoke Protection mode. This action fulfilled the Control Room Emergency Ventilation safety function and allowed the 2A Control Room Emergency Ventilation (CREV) subsystem to be declared OPERABLE. Required Action B.1 of Technical Specification (TS) 3.7.3 (be in Mode 3 within 12 hours) was exited.</br>This report applies to both Units 1 and 2 and is being made in accordance with 10 CFR 50.72(b)(3)(v)(D), as a condition that at the time of discovery could have prevented the fulfillment of the safety function of a system needed to mitigate the consequences of an accident.</br>The safety significance of this event is considered minimal. The condition with the Control Building Exhaust Damper (20) is intermittent. The solenoid valve for this damper was recently replaced on 5/3/2008. The post maintenance test included ensuring this damper would close on demand and was completed satisfactory. In addition, this same test was performed on the other division of CREV logic on 5/17/2008, the Control Building Exhaust Damper and Exhaust Fan functioned as required. In addition, the exhaust damper and fan operated properly, when manually operated from the Control Room, while manually placing the CREV system in service. </br>All systems functioned as required except for the Control Building exhaust fan.</br>2A Control Building Emergency Ventilation (CREV) subsystem placed in the Radiation/Smoke. The NRC Resident Inspector has been notified. Repair options for the Control Building Exhaust Damper are being developed.ilding Exhaust Damper are being developed.
21:35:00, 19 June 2008 +
44,309 +
00:15:00, 20 June 2008 +
21:35:00, 19 June 2008 +
At 17:35 hours on June 19, 2008, the Contr … At 17:35 hours on June 19, 2008, the Control Room authorized post maintenance testing following replacement of solenoid valves affecting the 2B Control Room Emergency Ventilation (CREV) subsystem. This testing was required to restore this Subsystem to OPERABLE following maintenance. This test inputs a Simulated high radiation signal into the logic for Control Building HVAC system and ensures that the Control Room Emergency Ventilation subsystem automatically aligns to the Radiation/Smoke Protection mode. During performance of this test, the Control Building Exhaust Fan Damper (2D) failed to close and the associated Control Building Exhaust Fan failed to trip as expected. These functions are required to occur to maintain a positive pressure in the Control Building during a high radiation in the Control Building ventilation intake plenum or during smoke intrusion into the Control Building. Since Brunswick has a shared control room, Unit 1 and Unit 2 entered Technical Specification (TS) 3.7.3,'Control Room Emergency Ventilation (CREV) System,' Required Action B.1 (i.e., be in Mode 3 within 12 hours).</br>At 1910, the 2A Control Room Emergency Ventilation (CREV) subsystem was manually placed in the Radiation/Smoke Protection mode. This action fulfilled the Control Room Emergency Ventilation safety function and allowed the 2A Control Room Emergency Ventilation (CREV) subsystem to be declared OPERABLE. Required Action B.1 of Technical Specification (TS) 3.7.3 (be in Mode 3 within 12 hours) was exited.</br>This report applies to both Units 1 and 2 and is being made in accordance with 10 CFR 50.72(b)(3)(v)(D), as a condition that at the time of discovery could have prevented the fulfillment of the safety function of a system needed to mitigate the consequences of an accident.</br>The safety significance of this event is considered minimal. The condition with the Control Building Exhaust Damper (20) is intermittent. The solenoid valve for this damper was recently replaced on 5/3/2008. The post maintenance test included ensuring this damper would close on demand and was completed satisfactory. In addition, this same test was performed on the other division of CREV logic on 5/17/2008, the Control Building Exhaust Damper and Exhaust Fan functioned as required. In addition, the exhaust damper and fan operated properly, when manually operated from the Control Room, while manually placing the CREV system in service. </br>All systems functioned as required except for the Control Building exhaust fan.</br>2A Control Building Emergency Ventilation (CREV) subsystem placed in the Radiation/Smoke. The NRC Resident Inspector has been notified. Repair options for the Control Building Exhaust Damper are being developed.ilding Exhaust Damper are being developed.
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22:34:22, 24 September 2017 +
00:15:00, 20 June 2008 +
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21:35:00, 19 June 2008 +
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