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This report is being made pursuant to 10CF … This report is being made pursuant to 10CFR50.72(b)(3)(ii)(B), Degraded or Unanalyzed Condition. During Division 1 Core Standby Cooling System (CSCS) valve replacement work, it was discovered that temporary seismic supports required to maintain this piping within the Safe Shutdown Earthquake (SSE) design envelope were not installed. This condition was discovered during the restoration phase of the maintenance and the requirements for the temporary supports no longer exist. At the time of discovery, the required permanent seismic qualified support system had been re-established. The Division 1 CSCS System is common to both units and circulates lake water from the Ultimate Heat Sink (UHS) to the Division 1 Residual Heat Removal (RHR) heat exchangers, Division 1 Diesel Generator cooler, Division 1 Emergency Core Cooling System (ECCS) area room coolers, Division 1 RHR Pump seal coolers, and the Low Pressure Core Spray (LPCS) motor coolers. During the period with the required seismic supports not installed, both Unit 1 and Unit 2 were in an unanalyzed condition due to the inability of the Division 1 CSCS piping to meet its seismic qualification. A postulated structural failure of the Division 1 CSCS piping during an SSE could affect areas containing redundant equipment due to flooding.</br>The licensee is investigating the failure to install the supports. The supports were only needed during the maintenance.</br>The licensee notified the NRC Resident Inspector.</br>* * * UPDATE AT 0025 EST ON 3/15/06 FROM T. NANCE TO W. GOTT * * *</br>On March 11, 2006, it was identified that temporary seismic supports required to maintain the Core Standby Cooling System piping within the Safe Shutdown Earthquake (SSE) envelope during valve replacement activities were not installed. This was reported under 10 CFR 50.72 (b)(3)(ii)(B) as a degraded or unanalyzed condition that significantly degrades plant safety.</br>Subsequent evaluations have been performed to demonstrate that the piping remained within the SSE envelope with the missing supports. These evaluations have concluded that the remaining supports were sufficient to ensure that piping would remain intact during an SSE. As such, this event notification is being retracted.</br>The licensee notified the NRC Resident Inspector.</br>Notified R3DO (D. Passehl)dent Inspector.
Notified R3DO (D. Passehl)
06:30:00, 11 March 2006 +
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06:36:00, 11 March 2006 +
06:30:00, 11 March 2006 +
This report is being made pursuant to 10CF … This report is being made pursuant to 10CFR50.72(b)(3)(ii)(B), Degraded or Unanalyzed Condition. During Division 1 Core Standby Cooling System (CSCS) valve replacement work, it was discovered that temporary seismic supports required to maintain this piping within the Safe Shutdown Earthquake (SSE) design envelope were not installed. This condition was discovered during the restoration phase of the maintenance and the requirements for the temporary supports no longer exist. At the time of discovery, the required permanent seismic qualified support system had been re-established. The Division 1 CSCS System is common to both units and circulates lake water from the Ultimate Heat Sink (UHS) to the Division 1 Residual Heat Removal (RHR) heat exchangers, Division 1 Diesel Generator cooler, Division 1 Emergency Core Cooling System (ECCS) area room coolers, Division 1 RHR Pump seal coolers, and the Low Pressure Core Spray (LPCS) motor coolers. During the period with the required seismic supports not installed, both Unit 1 and Unit 2 were in an unanalyzed condition due to the inability of the Division 1 CSCS piping to meet its seismic qualification. A postulated structural failure of the Division 1 CSCS piping during an SSE could affect areas containing redundant equipment due to flooding.</br>The licensee is investigating the failure to install the supports. The supports were only needed during the maintenance.</br>The licensee notified the NRC Resident Inspector.</br>* * * UPDATE AT 0025 EST ON 3/15/06 FROM T. NANCE TO W. GOTT * * *</br>On March 11, 2006, it was identified that temporary seismic supports required to maintain the Core Standby Cooling System piping within the Safe Shutdown Earthquake (SSE) envelope during valve replacement activities were not installed. This was reported under 10 CFR 50.72 (b)(3)(ii)(B) as a degraded or unanalyzed condition that significantly degrades plant safety.</br>Subsequent evaluations have been performed to demonstrate that the piping remained within the SSE envelope with the missing supports. These evaluations have concluded that the remaining supports were sufficient to ensure that piping would remain intact during an SSE. As such, this event notification is being retracted.</br>The licensee notified the NRC Resident Inspector.</br>Notified R3DO (D. Passehl)dent Inspector.
Notified R3DO (D. Passehl)
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