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05000336/FIN-2009004-032009Q3MillstoneUnit 2 A Reactor Coolant Pump Seal Cooler WeldDuring a recent Problem Identification and Resolution Inspection, the inspectors reviewed Dominion\'s conformance with the specifications of ASME Code Section XI and Section III relative to repair of a pressure boundary leak condition that affected the A RCP seal cooler piping, a ASME Class I component. Dominion identified a weld leak affecting the Millstone Unit 2, A RCP seal cooler piping on July 13, 2009, an ASME Class I component. The affected piping is 1.5aD and is part of the reactor coolant pressure boundary. The repair was initiated in accordance with ASME Section XI, which directed Dominion to ASME Section III for weld repair completion and post repair non-destructive examination. On July 17, 2009, Dominion completed the repair welding, and subsequently returned the plant to power on July 25, 2009. Aspects concerning Dominion\'s performance with regard to this repair activity remain to be reviewed and assessed to ascertain conformance with the applicable ASME Code and NRC regulatory requirements. URI 05000336/2009004-03.
05000336/FIN-2010004-012010Q3MillstoneFailure to Promptly Identify and Correct the Source of a Unit 2 RCS Pressure Boundary LeakThe inspectors identified a Green, NCV of 10 CFR 50, Appendix B, Criterion XVI, Corrective Actions, for Dominion\'s failure to promptly identify and correct the source of a reactor coolant system (RCS) pressure boundary leak from July 3, 2009, through July 13, 2009. Dominion subsequently repaired the leak and returned to 100 percent power. The inspectors determined that Dominion\'s failure to promptly identify and correct the cause of pressure boundary leakage is a performance deficiency that was reasonably within Dominion\'s ability to foresee and correct and should have been prevented. This issue is more than minor because the issue is similar to NRC Inspection Manual Chapter (IMC) 0612, Appendix E, and minor example 2.g. The inspectors determined that the issue affected the Initiating Events Cornerstone objective to limit the likelihood of those events that upset plant stability and challenge critical safety functions during shutdown as well as power operations. The inspectors concluded that this condition, assuming the worst case degradation, would not have affected other mitigating systems resulting in a total loss of their safety function. Accordingly, the finding was determined to be of very low safety significance (Green) using IMC 609, Attachment 0609.004, Phase 1 Screening Worksheet. The inspectors determined that this issue had a crosscutting aspect in the Problem Identification and Resolution cross-cutting area, Corrective Action Program component, because Dominion did not identify the pressure boundary leakage completely, accurately, and in a timely manner commensurate with its safety significance. (P.1 (a))
05000336/FIN-2010004-022010Q3MillstoneFailure to Perform an ASME Code-compliant Radiographic Examination on a Class 1 Weld on the Unit 2 \'A\' RCP Seal Cooler PipingThe inspectors identified a Severity Level IV, NCV of 10 CFR 50.55a(2)( c)( 1) and 10 CFR 50.55a(3), when Dominion did not perform an ASME Code compliant radiographic examination for a leak in a Class 1 weld on the Unit 2 \'A\' RCP seal cooler piping before returning the system to service. Dominion was out of compliance with 10 CFR 50.55a(2)(c)(1), 10 CFR 50.55a(3), and Section III of the American Society of Mechanical Engineers (ASME) Code between July 24, 2009, and November 10,2009. The NRC granted verbal relief from the 10 CFR 50.55a(2)(c)(1), 10 CFR 50.55a(3), and the ASME Code requirements on November 10, 2009. Subsequently, the relief request was approved, in writing, by the NRC on April 26, 2010. In accordance with IMC 0612, Appendix B, Section 1-2, this finding had the potential to impact the NRC\'s ability to perform its regulatory function because Dominion verbally informed the NRC on July 17, 2009, that they would repair the affected component in accordance with ASME Code requirements. However, due to Dominion\'s misinterpretation of the ASME Code, Dominion did not subsequently inform the NRC of its inability to meet Code requirements (i.e. perform a Code compliant radiographic examination of the affected weld) before returning the plant to service. As a result, Dominion\'s actions had impeded the NRC\'s ability to evaluate and determine the efficacy of the licensee\'s actions. The issue was characterized as Severity Level IV because it is similar to the example provided in the NRC Enforcement Policy Section 6.1.d.2, in that, it involved a violation of NRC requirements that resulted in a condition evaluated as having very low safety significance (i.e., Green) by the Significance Determination Process (SDP). The inspector determined that this issue had a crosscutting aspect in the Human Performance cross-cutting area, Decision Making component, because Dominion did not use conservative assumptions in their decision making when they concluded that Code relief from the NRC would not be necessary to accomplish the repair. (H.1 (b))
05000336/FIN-2010004-032010Q3MillstoneFailure to Implement Timely Corrective Actions for a Degraded Unit 2 FRV Results in Manual Reactor TripA self-revealing finding of very low safety significance (Green) was identified for Dominion\'s failure to implement timely corrective actions for a degraded Unit 2 feedwater regulating valve (FRV) in accordance with procedure PI-AA-200, Corrective Action. Specifically, two weeks after the issue was first identified, the #2 FRV further degraded causing Dominion to trip the reactor when the #2 steam generator (SG) level could not be adequately controlled. Dominion subsequently repaired the FRV and returned the plant to 100 percent power. The inspectors determined that Dominion\'s failure to implement timely corrective actions for a degraded #2 FRV in accordance with procedure PI-AA-200, Corrective Action, was a performance deficiency. This finding is more than minor because it was similar to NRC Inspection Manual Chapter 0612, Appendix E, Examples of Minor Issues, Example 4f, in that the failure to correct a condition adverse to quality led to a reactor trip. The finding was associated with the equipment performance attribute of the Initiating Events cornerstone and affected the cornerstone objective of limiting the likelihood of those events that upset plant stability and challenge critical safety functions during power operations. Specifically, Dominion\'s failure to implement timely corrective actions for the #2 FRV caused the operators to manually trip the reactor when the #2 SG level could not be controlled. The inspectors determined that this finding had a cross-cutting aspect in the Problem Identification and Resolution cross-cutting area, Corrective Action Program component, because Dominion did not take appropriate corrective action to address the degraded #2 FRV in a timely manner, commensurate with its safety significance. (P.1(d)).
05000336/FIN-2010004-042010Q3MillstoneLicensee-Identified Violation10 CFR 50, Appendix B, Criterion V, Instructions, Procedures, and Drawings, requires, in part, that activities affecting quality shall be prescribed by documented instructions, procedures, or drawings, of a type appropriate to the circumstances and shall be accomplished in accordance with these instructions, procedures, or drawings. Contrary to this, Dominion had no documented procedure for bypassing undervoltage protection for the vital buses. As a result, on October 7, 2009, Dominion bypassed the undervoltage protection for the vital buses and rendered both EDGs inoperable for approximately seven hours. Upon discovery, Dominion restored the undervoltage protection and entered the issue into their corrective action program (CR351389). The finding is of very low safety significance because of the short duration of the inoperability, and because both EDGs could be manually started from the Control Room.
05000336/FIN-2010004-052010Q3MillstoneLicensee-Identified ViolationTS 3.6.6.2 requires that if secondary containment is inoperable, it must be restored to operable status within 24 hours or the plant must be shutdown. Contrary to this, from May 13, 2010, until May 27, 2010, two sets of auxiliary building tunnel exhaust dampers were open, which rendered secondary containment inoperable. Upon discovery, Dominion immediately restored operability by closing one set of dampers and placed the issue into their corrective action program (CR382686). The finding is of very low safety significance because it only represented a degradation of the radiological barrier function for the auxiliary building.
05000336/FIN-2010004-062010Q3MillstoneLicensee-Identified Violation10 CFR 50 Appendix B, Criterion III, Design Control requires, in part, that measures shall be established to assure that the applicable design basis for structures, systems, and components, are correctly translated into specifications, drawings, procedures, and instructions. Contrary to this, from approximately 1995 until August 13, 2010, Dominion failed to ensure that the design basis for the reactor coolant system was maintained when it specified and installed flex hoses with an insufficient pressure rating. Upon discovery, Dominion entered the issue into their corrective action program (CR 390963), shutdown the plant, and replaced the hoses with flex hoses of the proper pressure rating. The finding is of very low safety significance because a failure of the hose would have resulted in a leak that was within the capability of the charging pumps.
05000336/FIN-2010004-072010Q3MillstoneLicensee-Identified ViolationTS 3.7.1.2 LCO (c) requires the TDAFW pump to be operable in Mode 1. If the pump is not operable, Action Statement (c) directs restoration within 72 hours after which a plant shutdown to Mode 3 in six hours is required. Contrary to this requirement, on August 23, 2010, the TDAFW pump failed its quarterly surveillance test and a review of prior surveillance tests indicated that the pump had been inoperable since June 30, 2010 (a period of 54 days). Dominion had not properly evaluated the results of the previous surveillance test. During both of these tests, the TDAFW pump failed to produce an acceptable discharge flow rate because the charging pump discharge relief valve, 3FWA*RV45, leaked by its seat. Upon discovery, Dominion declared the TDAFW pump inoperable and promptly repaired the relief valve. Dominion entered the issue into their corrective action program (CR392003), and restored the TDAFW pump to an operable condition. The finding is of very low safety significance because the TDAFW pump was later determined to be available to support core heat removal during the period when the relief valve was degraded.
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