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On July 19, 2012, at 7:34 a.m. Eastern Day … On July 19, 2012, at 7:34 a.m. Eastern Daylight Time (EDT), the fuses for two Unit 1 steam generator stop valves (specifically the associated dump valves) blew. Without power, the valves would not open to cause a closure of the associated steam generator stop valves. The failure affected the Train B portion; Train A remained operable. The blown fuses rendered one train of ESFAS inoperable and the licensee entered TS 3.3.2 Condition C which requires restoration to operable within 6 hours. If the completion time cannot be met, TS 3.3.2 condition I required the licensee to enter Mode 3 within 6 hours and Mode 4 within 12 hours. Since the licensee could not complete repairs within 6 hours, the licensee began a down power and requested that the NRC exercise discretion and extend the required action time to 30 hours to enter Mode 3 and 36 hours to enter Mode 4. The licensee verbally requested the discretion via telephone and the NRC granted discretion, effective at 7:34 p.m. EDT (Notice of Enforcement Discretion (NOED) 12-3-002, ML12207A516). During the telephone call, the licensee informed the NRC that repairs would be completed within 24 hours and the risk associated with discretion was low. The licensee also proposed a number of compensatory measures to mitigate the risk associated with operating during the period of discretion. The licensee completed repairs and exited the limiting condition for operation at 8:30 p.m. EDT the same day. The inspectors responded to the control room after being informed of the inoperable steam generator stop valves. Initially, the licensee entered TS 3.0.3 due to an erroneous conclusion that the failure of the solenoids rendered two steam generator stop valves inoperable. Subsequently, the licensee determined that a TS 3.0.3 entry was not required and that the correct TS was TS 3.3.2, ESFAS Instrumentation. The licensee then entered the correct TS condition based on the time when the fuse blew. The inspectors reviewed the licensees actions and concluded that the delay in recognizing the correct TS did not result in the licensee failing to perform a required action within the specified completion time. The inspectors observed the licensees actions in the control room to understand the condition and evaluate the cause. Over the course of the day, the inspectors monitored the licensees troubleshooting activities and efforts to correct the condition without requiring enforcement discretion. At 3:39 p.m. EDT, the licensee commenced a down power to support compliance with TS 3.3.2 condition I. The licensee identified that a short occurred between the associated power distribution panel and a solenoid. Because repairs could not be completed before the TS 3.3.2 completion time expired, the licensee requested, and the NRC granted, an NOED. The licensee stopped the shutdown at 6:09 p.m. EDT after the NRC granted the NOED. During the period of discretion, the inspectors verified through plant walk downs, observation, document reviews, and discussions with operations and engineering personnel, that the licensee appropriately implemented the compensatory actions as approved. At 8:30 p.m. EDT, the licensee restored the system to operable and exited the NOED. The inspectors reviewed the licensees written NOED to validate that the information was consistent with information provided by the licensee during the NOED telephone call. The licensees cause evaluation was not complete at the end of the inspection period. Therefore, the inspectors will review the cause analysis and corrective actions after the evaluation is completed. This issue will be an unresolved item (URI) until licensee completion and NRC review of causal analysis and follow-up actions for the issue (URI 05000315/2012004-02, Follow-up Inspection of Actions from NOED 12-3-002).Inspection of Actions from NOED 12-3-002).
23:59:59, 30 September 2012 +
23:59:59, 30 September 2012 +
Has query"Has query" is a predefined property that represents meta information (in form of a <a rel="nofollow" class="external text" href="https://www.semantic-mediawiki.org/wiki/Subobject">subobject</a>) about individual queries and is provided by <a rel="nofollow" class="external text" href="https://www.semantic-mediawiki.org/wiki/Help:Special_properties">Semantic MediaWiki</a>.
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6.944444e-5 d (0.00167 hours, 9.920635e-6 weeks, 2.283e-6 months) +, 1.388889e-4 d (0.00333 hours, 1.984127e-5 weeks, 4.566e-6 months) +, 3.472222e-4 d (0.00833 hours, 4.960317e-5 weeks, 1.1415e-5 months) +, 4.166667e-4 d (0.01 hours, 5.952381e-5 weeks, 1.3698e-5 months) + and 2.777778e-4 d (0.00667 hours, 3.968254e-5 weeks, 9.132e-6 months) +
Modification date"Modification date" is a predefined property that corresponds to the date of the last modification of a subject and is provided by <a rel="nofollow" class="external text" href="https://www.semantic-mediawiki.org/wiki/Help:Special_properties">Semantic MediaWiki</a>.
00:46:09, 21 February 2018 +
23:59:59, 30 September 2012 +