|Entered date||Site||Region||Reactor type||Event description|
|ENS 54179||23 July 2019 19:50:00||San Onofre||NRC Region 4||On 7/23/2019 at 1405 PDT, San Onofre Nuclear Generating Station (SONGS) made a required formal notification to the Regional Water Quality Control Board for the state of California concerning a monthly oil sample of the oil removal system. The sample was analyzed to contain 42 ppm oil. This number exceeds the daily instantaneous maximum of 20 ppm. An additional sample was taken approximately one minute later and was analyzed to contain 8.1 ppm oil, potentially indicating a problem with the initial sample. Additional investigation is underway and a written follow-up report will be submitted to the Regional Water Quality Control Board within 5 days in accordance with the National Pollutant Discharge Elimination System permit. The licensee will inform NRC Region IV staff.|
|ENS 53642||3 October 2018 19:39:00||San Onofre||NRC Region 4||At 1135 PDT on October 3, 2018, Southern California Edison (SCE) determined a SCE supervisor failed a random breathalyzer test for alcohol during a random Fitness-for-Duty (FFD) test. The employee's unescorted access to San Onofre Nuclear Power Plant has been suspended."|
|ENS 53580||5 September 2018 12:53:00||San Onofre||NRC Region 4||At approximately 0608 Pacific Daylight Time (PDT), the Control Room was notified of a SONGS SCE (San Onofre Nuclear Generating Station Southern California Edison) employee experiencing a non-work related medical emergency outside the protected area, inside the owner controlled area. SONGS fire brigade was dispatched. Camp Pendleton Fire ambulance was requested. At 0644 (PDT) Camp Pendleton Fire department in communication with a doctor determined the victim is deceased. This notification is being made in accordance with 10 CFR 50.72(b)(2)(xi) for a situation related to the health of on-site personnel for which a notification to other government agencies is planned. California Highway Patrol and Coroner notified and expect the California Occupational Safety and Health Administration (Cal-OSHA) will be notified. NRC Region IV was notified (approximately 0900 PDT) as SONGS does not have a NRC resident inspector."|
|ENS 52252||19 September 2016 18:17:00||San Onofre||NRC Region 4||CE||At 1230 (PDT) on 9/19/16, SONGS (San Onofre Nuclear Generating Station) made an offsite notification to the San Diego Regional Water Quality Control Board in regards to an oily waste water release to the environment in excess of allowable limits. On 9/15/16, the Unit 3 oily waste sump overflowed. An estimated 1500 gallons was released to the intake which is pumped to the outfall. A sample was taken during the end of the overflow; no visual indication of oil and grease was noted. The sample analysis completed on 9/19/16 indicated a result that exceeded SONGS' NPDES (National Pollutant Discharge Elimination System) instantaneous maximum limit of 20 ppm; results were 34.4 ppm. The licensee will inform NRC Region IV staff.|
|ENS 52047||27 June 2016 22:14:00||San Onofre||NRC Region 4||Westinghouse PWR 3-Loop|
A non-licensed contract employee had a confirmed positive for alcohol following a for-cause fitness-for-duty test. The employee's access to the plant has been terminated. This information will be sent to the NRC Region 4 Office as San Onofre no longer has a resident.
In the event report, the individual was described as a contract supervisor, thus meeting the reporting threshold. (the violation of the FFD policy was that he failed a for-cause test for alcohol). Recently, an NRC review of SONGS' 2016 Annual Fitness for Duty report found that SONGS described that test failure as 'not reportable' and that the labor category was 'Maintenance (Craft).' After reviewing the data, Access Authorization confirmed that the individual was a Union Maintenance Foreman (not a supervisor). The event was not reportable." SONGS will be notifying NRC Region 4. Notified R4DO (O'KEEFE) and FFD E-mail Group.
|ENS 51554||19 November 2015 19:10:00||San Onofre||NRC Region 4||CE||A review of operations log data revealed the Unit 2 Spent Fuel Pool temperature was allowed to drift approximately two degrees below the accepted analyzed temperature of 68 degrees F. The Extent of Condition is under review and the number of instances has not been fully determined. It is possible Unit 3 may have also been affected. As described in the San Onofre UFSAR, Section 18.104.22.168 'Design Basis for Fuel Storage and Handling,' one of the conditions assumed in meeting the design basis, is as follows: the most adverse delta-k (reactivity change) was analyzed for a pool temperature range from 68 degree F to 160 degree F. Although the temperature decrease is considered unlikely to have a significant impact on the results of the analysis, it is being reported under 10 CFR 50.72(b)(2) as an unanalyzed condition because there is at this time no analysis of record for the reduced temperature condition. There were and continue to be no observed, abnormal effects from the temperature drop below 68 degrees F, and no impact on the health or safety of plant personnel of the public. Re-analysis is in progress and is expected to demonstrate that the criticality acceptance criteria of 10CFR50.68 were met at all times. The licensee notified the Regional NRC Contact.|
|ENS 51018||27 April 2015 18:56:00||San Onofre||NRC Region 4||CE||Notification was made to the San Diego Regional Water Quality Control Board, and a message was left for exceeding the daily maximum parts per million (ppm) of oil and grease in the North Industrial Area Yard Drain Sump. Sump pumps are currently in "OFF" and the site is investigating. The oil in the drain sump did not reach "reportable quantities" and did not require notifying other Federal Agencies.|
|ENS 50470||18 September 2014 18:43:00||San Onofre||NRC Region 4||CE||Today, at 1235 (PDT), San Onofre made the decision to notify offsite agencies (San Diego Regional Water Quality Control Board and Environmental Protection Agency if directed by SDRWQCB). Initial contact made with the San Diego Regional Water Quality Control Board was at 1333 (PDT) on 9/18/14. The subject of the report is listed below: On September 15, 2014, during a review of the NPDES (National Pollutant Discharge Elimination System) self-monitoring reports, SCE SONGS (Southern California Edison San Onofre Nuclear Generating Station) environmental staff discovered annual and semi-annual samples and required reports due in 2014 were not submitted on time and are now past due: - The missed samples and associated reports are non-radiological in nature - All parameters (physical and analytical data) in past Semi-annual and Annual reports have been in compliance with the NPDES permit. The licensee informed the NRC Resident Inspector.|
|ENS 50115||14 May 2014 18:07:00||San Onofre||NRC Region 4||CE||SONGS (is) making a 4-Hour notification per 10CFR72.75 (b) to the NRC Operations Center regarding the following: There has been a fire in the vicinity of the station. The fire is not on plant property and has not challenged station operations. Entry into SONGS' Emergency Plan and activation of the Emergency Response Organization is not required at this time. Because of the fire near the plant, Southern California Edison will be making a press release today to update the public as to the situation at the plant. The licensee notified an onsite NRC Inspector.|
|ENS 49975||31 March 2014 14:44:00||San Onofre||NRC Region 4||CE|
On March 28, 2014 at 2110 PDT, station staff felt a minor seismic event, which was verified on the NEIC (National Earthquake Information Center). On-shift staff reviewed basis documentation and EAL (Emergency Action Levels) classification, and concluded the event was below the threshold to classify the event. During post event reviews (conducted on 3/31/2014), it has been determined that those events met the classification criteria for declaration of a Notification of Unusual Event for a seismic event as specified by the Emergency Plan. No emergency situation exists at this time.
Site personnel did perform the steps of the Earthquake abnormal operating procedure even though the entry requirements were not met. There were no plant or equipment issues identified during the site walk downs.
The licensee has notified the NRC Resident Inspector, the State of California and other Local authorities.
|ENS 48913||11 April 2013 04:29:00||San Onofre||NRC Region 4||CE||At 2253 PDT on 4/10/13, SONGS experienced degraded on-site radio communications during planned maintenance on radio systems. Radio communications were restored at 2315 PDT. The licensee will notify the NRC Resident Inspector.|
|ENS 48428||21 October 2012 13:03:00||San Onofre||NRC Region 4||CE||The control room was notified that an unknown quantity of H2 gas (classified as a minor coupling leak (identified with Snoop liquid leak detector)) is currently being released to the air from the Unit 2 Full Flow Hydrogen skid. The Environmental Protection Group reported the leak to the California Emergency Management Agency (Cal EMA) at 0809 PDT and the San Diego Department of Environmental Health at 0812 PDT lAW (plant) procedure S0123-XV-17.3, 'Spill Contingency Plan'. The Hydrogen Gas leak is currently still in progress. There is no gas collection areas. Maintenance is in the process of taking action to terminate the leak. The licensee notified the NRC Resident Inspector.|
|ENS 48344||25 September 2012 22:50:00||San Onofre||NRC Region 4||CE||The control room was notified by the Environmental Protection Group that 43 lbs of Freon was released (from an air conditioning unit) at the Administration Warehouse Supply/Shop, not in the Protected Area, and that it was reported to the California Emergency Management Agency at 17:19 PDT and San Diego County at 17:12 PDT, per lAW procedure SO123-XV-17.3, 'Spill Contingency Plan'. There is no longer a Freon release in progress. The licensee has notified the NRC Resident Inspector.|
|ENS 48232||26 August 2012 16:00:00||San Onofre||NRC Region 4||CE|
A Notice of Unusual Event (NOUE) was declared at San Onofre due to an earthquake felt on site (EAL HU1.1). The US Geological Survey indicates that there was a 5.3 magnitude earthquake near Brawley California, about 125 miles southeast of the plant. There were no indication of any impact to site operations other than being felt by personnel. Equipment inspections and walkdowns are in progress. The licensee has notified state and local authorities. The NRC Resident Inspector will be notified. Notified other FEDS (FEMA, DHS, DHS NICC and Nuclear SSA via email).
On August 26, 2012 at 1346 PDT, San Onofre exited the Unusual Event based on an earthquake felt on site. Shortly after exiting the UE, the licensee felt more shaking in the control room. The licensee confirmed with the US Geological Survey that there has been an aftershock. The aftershock was approximately the same magnitude (5.4) and location as the original earthquake (about 125 southeast of the site). The licensee declared another unusual event at 1403 PDT. The licensee will re-perform all equipment walkdowns and inspections. The NRC Resident Inspector has been notified and is reporting to the site. R4DO (Hay), NRR EO (Lubinski), and IRD (Gott) notified.
Exited the NOUE HU1.1 - Earthquake at 2017 PDT on 8/26/12. The licensee will notify the NRC Resident Inspector. Notified the R4DO (Hay), NRR (Lubinski), IRD (Gott), DHS, FEMA, and DHS NICC.
|ENS 47856||20 April 2012 16:29:00||San Onofre||NRC Region 4||CE||San Onofre Unit 2 declared an Unusual Event at 1249 PDT today due to an electrical fire within a fire detection panel (2L319) in the Unit 2 turbine building. The fire was declared extinguished at 1314 PDT after the panel was de-energized. The location of the fire had no impact on plant operation, equipment, or personnel safety. No offsite assistance was necessary. The licensee exited the Unusual Event at 1341 PDT after the licensee confirmed that the fire was terminated and there was no ongoing risk to the plant. The licensee notified state and local authorities and the NRC Resident Inspector. The NRC Operations Center notified other Federal Agencies (DHS SWO, FEMA Ops, DHS NICC, and NuclearSSA via e-mail).|
|ENS 47744||14 March 2012 18:20:00||San Onofre||NRC Region 4||CE|
On January 31, 2012, Unit 3 was shut down due to detection of a tube leak in one Steam Generator (SG). The shutdown was previously reported on Event Notification # 47628. Southern California Edison (SCE) has been performing in-situ pressure testing with non-radioactive water on tubes with significant wear indications. On March 14, 2012, at approximately 1120 PDT, Unit 3 Steam Generator (SG) E088 Tube R106 C78 did not meet the target performance criteria because leakage exceeded 0.5 gallons per minute at the maximum pressure achieved during the test (2,884 psig). This was the leaking tube that resulted in the Unit 3 shutdown. Subsequently, two additional tubes in Unit 3 SG E088 did not meet the target performance criteria as follows: at 1249 PDT, Tube R102 C78 exceeded 0.5 gallons per minute at 3,268 psig and at 1425 PDT, Tube R104 C78 exceeded 0.5 gallons per minute at 3,180 psig. These occurrences are reportable as an 8-hour notification to the NRC in accordance with 10 CFR 50.72(b)(3)(ii)(A). Testing and inspection of Unit 3 steam generator tubes is ongoing to determine the extent and cause of the observed wear. A follow-up notification will be made for additional in-situ pressure test failures. The extent and cause of the condition will be addressed in the follow-up licensee event report that will be submitted in accordance with 10 CFR 50.73(a)(2)(ii)(A). Defective tubes will be removed from service as required prior to Unit 3 plant startup. Unit 2 has been shut down since January 9, 2012 for a scheduled refueling outage. SCE previously performed in-situ pressure testing of the tube with the most wear in Unit 2. Results from this test demonstrated that the tube met the target performance criteria. The NRC Resident Inspector has been notified of this event.
In-situ pressure testing on Unit 3 steam generator tubes was started on March 14, 2012 and is ongoing. On March 15, 2012, four additional tubes in Unit 3 SG E088 did not meet the target performance criteria of three-times normal pressure conditions as follows: (1) At 1109 PDT, Tube R100 C80 failed at 4,739 psig; (2) at 1437 PDT, Tube R107 C77 failed at 5,160 psig; (3) at 1604 PDT, Tube R101 C81 failed at 4,889 psig; and (4) at 1734 PDT, Tube R98 C80 failed at 4,886 psig. Testing and inspection of Unit 3 steam generator tubes is ongoing to determine the extent and cause of the observed wear. Follow-up notifications will be made for any additional in-situ pressure test failures." The licensee notified the NRC Resident Inspector. Notified R4DO (Cain).
In-situ pressure testing on Unit 3 steam generator tubes was started on March 14, 2012 and is ongoing. On March 16, 2012, one additional tube in Unit 3 SG E088 did not meet the target performance criteria of three-times normal pressure conditions as follows: at 1216 PDT, Tube R99 C81 failed at 5,026 psig. Testing and inspection of Unit 3 steam generator tubes is ongoing to determine the extent and cause of the observed wear. Follow-up notifications will be made for any additional in-situ pressure test failures. The licensee notified the NRC Resident Inspector. Notified R4DO (Cain).
|ENS 47628||31 January 2012 22:58:00||San Onofre||NRC Region 4||CE||At 1505 PST, Unit 3 entered Abnormal Operation Instruction S023-13-14 'Reactor Coolant Leak' for a steam generator leak exceeding 5 gallons per day. At 1549 PST, the leak rate was determined to be 82 gallons per day. At 1610 PST, a leak rate greater than 75 gallons per day with an increasing rate of leakage exceeding 30 gallons per hour was established and entry into S023-13-28 'Rapid Power Reduction' was performed. At 1630 PST, commenced rapid power reduction per S023-13-28 'Rapid Power Reduction'. At 1731 PST, with reactor power at 35% the Unit was manually tripped. At 1738 PST, Unit 3 entered Emergency Operation Instruction S023-12-4 'Steam Generator Tube Rupture'. At 1800 PST the affected steam generator was isolated. All control rods fully inserted on the trip. Decay heat is being removed thru the main steam bypass valves into the main condenser. Main feedwater is maintaining steam generator level. No relief valves lifted during the manual trip. The plant is in normal shutdown electrical lineup. Unit 2 is presently in a refueling outage and was not affected by this event. The licensee has notified the NRC Resident Inspector. The licensee has issued a press release.|
|ENS 47550||23 December 2011 15:18:00||San Onofre||NRC Region 4||CE||At 0500 PST 12/23/2011, ERDS communication VPN (Virtual Private Network) link with the NRC was interrupted during an automatic swap between computer servers. Restoration of the communication link is expected to be restored by 1430 PST. The licensee will notify the NRC Resident Inspector.|
|ENS 47481||28 November 2011 12:34:00||San Onofre||NRC Region 4||CE||During the regeneration of the Unit 2 full flow condensate polishing demineralizer (FFCPD) resin, 5 percent sulfuric acid briefly overflowed from the bermed area. The majority of the acid went into the floor drains in the FFCPD area and then to the turbine building sump system. An estimated quantity of 2 gallons of sulfuric acid was released into the storm drains that discharged into the circulating water system. The quantity released was well below the reportable quantity. The fire department and environmental/hazmat team were contacted and responded. Precautionary notifications were made by SCE to: - California Emergency Management Agency - San Diego Dept. of Environmental Health. The cause of the leak has been corrected and no additional discharge is anticipated. The licensee will notify the NRC Resident Inspector.|
|ENS 47401||1 November 2011 18:08:00||San Onofre||NRC Region 4||CE|
On November 1, 2011 at 1450 PDT, San Onofre Unit 3 declared an ALERT and entered EAL HA3.1 due to an ammonia leak that prevented access to local areas. The plant is in a stable condition while the leakage is being secured. The turbine building on Unit 3 has been evacuated. Plant personnel are in the process of verifying no presence of ammonia in the turbine building. There was no impact on Unit 2.
At 1807 PDT licensee exited the ALERT and EAL HA3.1. The leak was at the Ammonia day tank and was flowing through an overflow vent into the berm. The high level in the Ammonia day tank was due to a leaking closed valve between the Demineralizer system and the ammonia bulk storage. The berm area was drained of all fluids. The wind direction caused the ammonia fumes to travel to the Unit 3 turbine deck. No off-site HAZMAT personnel came on-site. At 1756 PDT the precautionary evacuation of on-site personnel was terminated. Unit 2 was not affected from this event. The NRC Resident Inspector was notified. Notified NRR EO (Fredrick Brown), R4DO (Vincent Gaddy, IRDMOC (Jeff Grant), DHS (Hill), DOE (Doyle), USDA (Krauf), FEMA (Fuller) and HHS (Fajardo).
On November 1, 2011, Southern California Edison notified the California Emergency Management Agency at 1755 PDT and the San Diego Department of Environmental Health at 1810 PDT that approximately 25 gallons of Ammonium Hydroxide was spilled under the Ammonium Hydroxide day tank located outside the Unit 3 turbine building. The spill was contained in a berm under the tank and subsequently cleaned up. Both Units 2 and 3 were at approximately 100% power at the time of the event. Notified the R4DO (Gaddy).