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On April 17, 2013 at 1600 (EDT), while performing a valve inspection/repair of the Unit 2 'A' Reactor Coolant Loop Fill Valve (2- RC-HCV-2556A), the as-found inspection results identified evidence of a suspected flaw causing leakage from the valve body to the threads of a stud housing of the valve. This valve is a 2 (inch) 316 SS (Stainless Steel) cast ASME XI (Class 1) 1500 psi valve body of a globe style design. Due to this design and the installed orientation, the RCS pressure medium fills the upper portion of the valve bonnet where the leak is located during normal plant operations. Therefore, this leakage would be considered pressure boundary leakage. 2-RC-HCV-2556A is currently isolated from the Reactor Vessel and is at atmospheric pressure. This inspection was performed in response to dry discolored boric acid identified during the normal operating pressure boric acid accumulation inspection procedure during the Spring 2013 Unit 2 refueling outage shutdown. An engineering evaluation of the suspected defect will be performed and corrective actions implemented. This event is reportable in accordance to 10CFR50.72(b)(3)(ii)(A) for, 'Any event or condition that results in the condition of the nuclear power plant, including its principal safety barriers, being seriously degraded'. The licensee notified the NRC Resident Inspector and local County Commissioners.

• * * RETRACTION FROM BOB PAGE TO CHARLES TEAL ON 6/12/13 AT 1109 EDT * * *

Event Number 48940 was made on April 17, 2013 in accordance with 10CFR50.72(b)(3)(ii)(A) to document a suspected flaw resulting in RCS pressure boundary leakage on Unit 2 'A' Reactor Coolant Loop Fill Valve (2-RC-HCV-2556A). North Anna Power Station is retracting this notification following completion of a cause analysis and metallurgical examination. The analysis determined that the valve leakage was due to the body-to-bonnet gasket joint. The original valve body was especially susceptible to gasket creep, which lead to a loss of sufficient sealing stress. This resulted in body-to-bonnet leakage, not a through-wall leak. Based on this analysis, the reporting requirements of 10CFR50.72(b)(3)(ii)(A) are not met and this event report is being retracted. The licensee has notified the NRC Resident Inspector. Notified R2DO (Ehrhardt).

On January 13, 2010, at about 1125 PST, Train A suction piping from the SONGS Unit 3 Refueling Water Storage Tank (RWST) was determined to be inoperable following detection of weld flaw indications during ultrasonic testing. Due to miscommunication, operators mistakenly declared the Train B Emergency Core Cooling System (ECCS) header inoperable at about 1125 and removed DC control power to the Train B ECCS pumps. This resulted in both trains of Unit 3 ECCS being inoperable and entry into the Technical Specification (TS) 3.0.3 one-hour shut down action. At 1140 PST, the DC control power was restored to the Train B ECCS pumps, Train B ECCS was declared operable, and TS 3.0.3 was exited. SCE is reporting this in accordance with 10 CFR 50.72(b)(3)(v) as an event that could have prevented the fulfillment of a safety function. SCE is further evaluating the indications found on Train A piping to determine if the piping is capable of performing its safety function. At the time of this occurrence, Unit 2 was in a Steam Generator Replacement Outage, and Unit 3 was at approximately 100% power. The licensee notified the NRC Resident Inspector.

• * * RETRACTION PROVIDED BY LEE KELLY TO DONG PARK AT 1402 EST ON 1/19/10 * * *

On January 13, 2010, SCE reported that both trains of Unit 3 Emergency Core Cooling System were inoperable for approximately 15 minutes because Train B ECCS was mistakenly taken out of service when weld flaw indications were found on Train A ECCS piping. This resulted in a condition that could have prevented the fulfillment of a safety function. Consequently, both trains of ECCS in Unit 3 were declared inoperable and the unit entered into Technical Specification 3.0.3 at 1134 PST (Time of Discovery). At 1140 PST, Train B ECCS was declared operable and TS 3.0.3 was exited. Event Notification 45628 was conservatively made because, although Train A ECCS piping remained capable of performing its safety function, this was not yet formally documented at the time the 8-hour report was due. Subsequently, an engineering evaluation was completed at 2308 PST on January 13, 2010, that demonstrates the as-found condition of the Train A ECCS piping was operable because the flaw meets the evaluation criteria of ASME Boiler and Pressure Vessel Code Case N-513-2. Since Train A ECCS piping was operable, this event did not constitute a condition that could have prevented the fulfillment of a safety function and is not reportable under 10 CFR 50.72(b)(3)(v)(D). Consequently, SCE is retracting the phone report to the NRC on January 13, 2010. The NRC Resident Inspector will be informed of this report. Notified R4DO (Werner).

On February 22, 2006, at 1000 PST, two tankers containing wastewater with trace levels of radioactivity departed San Onofre Nuclear Generating Station (SONGS) Unit 1 Industrial Site for Clive, Utah. Each truck contained about 4500 gallons of water. At about 0400 PST February 23, 2006, SCE was notified by the trucking company (Triad Transport Company) that minor leakage from a valve on top of one of the trucks had been observed. The leakage was observed while the truck was stopped in Parawan, Utah approximately 4 hours from its destination. The driver of the truck immediately notified his management who traveled to the site, identified the origin of the leak as spray from a valve on top of the truck, relieved the tank pressure from a vent valve, and stopped the leak. Dampness was observed on the ground beside the tanker. Unconfirmed measurements indicate radiation levels are near background. SCE has dispatched a team to the site to coordinate remediation efforts as necessary. The second tanker has arrived at the site in Clive, Utah and no leakage was observed during receipt inspection. The Director of the Utah's Division of Radiation Control and the NRC Resident Inspectors have been notified of this occurrence. At the time of this report, Unit 1 was undergoing decommissioning. The activity from the radionuclides in the entire truck totaled 70.9 mCi, and primarily consisted of Cs-137 (41 mCi), Ni-63 (15 mCi), and Co-60 (5 mCi). The transport company notified the National Response Center. The truck traveled thru 4 States: CA, NV, AZ UT.

• * * UPDATE FROM C. WILLIAMS TO M. RIPLEY 1607 EST 03/01/06 * * *

On February 23, 2006, SCE notified the NRC that a small leak had been identified from a tanker that was transporting wastewater with trace levels of radioactivity from SONGS to Clive, Utah. That incident was reported to the NRC in accordance with 10CFR50.72.(b)(2)(xi) and the Utah Division of Radiation Control. SCE is updating this report to provide the NRC with the following remediation status: 1. SCE has decontaminated the tanker exterior and the leaking flange has been repaired. On February 24, 2006, the tanker completed its trip to the disposal site in Clive, Utah. Enroute, SCE personnel followed the tanker and inspected the flange at planned stops every hour. No leakage was observed and the tanker was received at the disposal facility without further incident. 2. SCE surveyed the truck stop in Parowan and identified two contaminated locations. The first was an asphalt area near the diesel pumps; the second was a gravel area where the truck had parked (about 150 yards from the diesel pumps). All contaminated materials including asphalt, concrete, dirt, and gravel were removed and shipped to the disposal site in Clive, Utah. No detectable levels of licensed material remain at the truck stop. 3. SCE surveyed personnel at the truck stop and determined that one individual had been contaminated. The pants leg of the trucking supervisor who had climbed on top of the truck to stop the leak had been contaminated (SCE took possession of the contaminated garment). There was no contamination on his skin. 4. Approval was obtained from the Utah Division of Radiation Control, the remediated areas of the truck stop were backfilled. 5. SCE is continuing to investigate the cause of the flange leak and will implement appropriate corrective actions. The NRC resident Inspectors have been notified of this update and will be provided with a copy of this update. Notified R4 DO (J. Whitten) and NMSS EO (S. Flanders)