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Susquehanna Unit 1 was being manually shut … Susquehanna Unit 1 was being manually shutdown on 10/13/2007 for a planned maintenance outage to address control cell friction. Prior to the shutdown five control rods had been declared inoperable due to control cell friction. When reactor power was lowered to 10% at 0220, entry into Tech Spec 3.1.3 was required for 'One or more BPWS groups with four inoperable control rods'. The completion time for this specification is 4 hours. The inoperability of the control rods condition cannot be cleared in the specified time. This condition results in the unit being in a 'Shutdown Required By Technical Specifications'. The required action is to be in Mode 3 within 12 hours. The Shutdown required by Technical Specifications is reportable as a 4 hour Non-Emergency report under 10 CFR 50.72(b)(2)(i).</br>Manual insertion of control rods will continue until all rods are fully inserted. Hot Shutdown is expected by 0800, 10/13/07.</br>Shutdown activities will continue to place the unit in cold shutdown.</br>A Press Release will be made concerning the planned maintenance outage.</br>The licensee notified the NRC Resident Inspector.</br>* * * UPDATE AT 1438 ON 11/7/2007 FROM TODD CREASY TO MARK ABRAMOVITZ * * *</br>On October 13, 2007, Susquehanna operators began the process of shutting down Unit 1 for a planned maintenance outage to address known control cell friction issues. Because four of five control rods declared inoperable during the operating cycle were located in the same Banked Position Withdrawal Sequence (BPWS) group, station personnel realized that conditions for entry into Technical Specification (TS) 3.1.3 'Control Rod Operability' Condition E would already be met when thermal power reached 10% rated thermal power during the shutdown. (NOTE: TS 3.1.3 Condition E is not applicable when thermal power is > 10%). With power less than or equal to 10%, TS 3.1.3 Condition E mandates restoration of control rods to operable status within 4 hours. If this 4 hour completion time is not met, TS 3.1.3 Condition F mandates that the plant enter Mode 3 (Hot Shutdown) within the next 12 hours. At 0220 hours on October 13, power was lowered to 10% power and TS 3.1.3 Condition E was entered. Control Room personnel, anticipating that the 4 hour restoration window allowed by Condition E would expire before the LCO could be cleared, reported the shutdown as a shutdown required by Tech Specs per 10 CFR 50.72(b)(2)(i). The ENS report was made proactively before the 4 hour restoration window had expired. Subsequently, the Unit 1 mode switch was placed to Shutdown (Mode 3) at 0610 hours on October 13. Because the timing of this mode change was within the 4 hour restoration window provided by TS 3.1.3 Condition E and because TS 3.1.3 is no longer applicable once Mode 3 is attained, the Condition requiring shutdown (Condition F) was never entered as a result of the inoperable BPWS rods as was initially reported via EN #43722.</br>However, TS 3.1.3 Condition F can also be directly entered if nine or more control rods become inoperable. As the controlled shutdown Progressed, four additional control rods had been conservatively declared inoperable because they failed to settle at latched position '00' in a reasonable period of time. (Note: LER reports 50-387/2005-002-00 and 50-387/2006-001-00 have previously discussed control rod friction experienced at Susquehanna.) Accordingly, TS 3.1.3 Condition F was entered at 0343 hours on October 13, 2007. This TS entry constitutes the initiation of a nuclear plant shutdown required by the plant's Technical Specifications and is thus reportable per 10CFR50.72(b)(2)(i).</br>Sufficient compensatory measures had been enacted such that TS 3.1.3 Condition F was no longer applicable by the time the controlled plant shutdown was completed. Therefore, the 60-day reporting that is necessary when a nuclear plant shutdown is completed per a plant's Tech Specs does not apply. (Reference: 10 CFR 50.73(a)(2)(i)(A))</br>The licensee notified the NRC Resident Inspector.</br>Notified the R1DO (Miller).sident Inspector.
Notified the R1DO (Miller).
06:20:00, 13 October 2007 +
43,722 +
05:15:00, 13 October 2007 +
06:20:00, 13 October 2007 +
Susquehanna Unit 1 was being manually shut … Susquehanna Unit 1 was being manually shutdown on 10/13/2007 for a planned maintenance outage to address control cell friction. Prior to the shutdown five control rods had been declared inoperable due to control cell friction. When reactor power was lowered to 10% at 0220, entry into Tech Spec 3.1.3 was required for 'One or more BPWS groups with four inoperable control rods'. The completion time for this specification is 4 hours. The inoperability of the control rods condition cannot be cleared in the specified time. This condition results in the unit being in a 'Shutdown Required By Technical Specifications'. The required action is to be in Mode 3 within 12 hours. The Shutdown required by Technical Specifications is reportable as a 4 hour Non-Emergency report under 10 CFR 50.72(b)(2)(i).</br>Manual insertion of control rods will continue until all rods are fully inserted. Hot Shutdown is expected by 0800, 10/13/07.</br>Shutdown activities will continue to place the unit in cold shutdown.</br>A Press Release will be made concerning the planned maintenance outage.</br>The licensee notified the NRC Resident Inspector.</br>* * * UPDATE AT 1438 ON 11/7/2007 FROM TODD CREASY TO MARK ABRAMOVITZ * * *</br>On October 13, 2007, Susquehanna operators began the process of shutting down Unit 1 for a planned maintenance outage to address known control cell friction issues. Because four of five control rods declared inoperable during the operating cycle were located in the same Banked Position Withdrawal Sequence (BPWS) group, station personnel realized that conditions for entry into Technical Specification (TS) 3.1.3 'Control Rod Operability' Condition E would already be met when thermal power reached 10% rated thermal power during the shutdown. (NOTE: TS 3.1.3 Condition E is not applicable when thermal power is > 10%). With power less than or equal to 10%, TS 3.1.3 Condition E mandates restoration of control rods to operable status within 4 hours. If this 4 hour completion time is not met, TS 3.1.3 Condition F mandates that the plant enter Mode 3 (Hot Shutdown) within the next 12 hours. At 0220 hours on October 13, power was lowered to 10% power and TS 3.1.3 Condition E was entered. Control Room personnel, anticipating that the 4 hour restoration window allowed by Condition E would expire before the LCO could be cleared, reported the shutdown as a shutdown required by Tech Specs per 10 CFR 50.72(b)(2)(i). The ENS report was made proactively before the 4 hour restoration window had expired. Subsequently, the Unit 1 mode switch was placed to Shutdown (Mode 3) at 0610 hours on October 13. Because the timing of this mode change was within the 4 hour restoration window provided by TS 3.1.3 Condition E and because TS 3.1.3 is no longer applicable once Mode 3 is attained, the Condition requiring shutdown (Condition F) was never entered as a result of the inoperable BPWS rods as was initially reported via EN #43722.</br>However, TS 3.1.3 Condition F can also be directly entered if nine or more control rods become inoperable. As the controlled shutdown Progressed, four additional control rods had been conservatively declared inoperable because they failed to settle at latched position '00' in a reasonable period of time. (Note: LER reports 50-387/2005-002-00 and 50-387/2006-001-00 have previously discussed control rod friction experienced at Susquehanna.) Accordingly, TS 3.1.3 Condition F was entered at 0343 hours on October 13, 2007. This TS entry constitutes the initiation of a nuclear plant shutdown required by the plant's Technical Specifications and is thus reportable per 10CFR50.72(b)(2)(i).</br>Sufficient compensatory measures had been enacted such that TS 3.1.3 Condition F was no longer applicable by the time the controlled plant shutdown was completed. Therefore, the 60-day reporting that is necessary when a nuclear plant shutdown is completed per a plant's Tech Specs does not apply. (Reference: 10 CFR 50.73(a)(2)(i)(A))</br>The licensee notified the NRC Resident Inspector.</br>Notified the R1DO (Miller).sident Inspector.
Notified the R1DO (Miller).
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