Semantic search
| Start date | Reporting criterion | Title | Event description | System | LER | |
|---|---|---|---|---|---|---|
| ENS 56487 | 26 April 2023 06:15:00 | 10 CFR 50.72(b)(2)(xi), Notification to Government Agency or News Release | Offsite Notification - Spilled Sodium Hypochlorite | The following information was provided by the licensee via email: On 4/25/2023 at approximately 2315 (MST) it was reported that there was possible sodium hypochlorite actively leaking near the 'A' essential spray pond (ESP). Upon investigation, it was determined that the 'low flow' line of sodium hypochlorite supply to the 'A' spray pond had developed a leak. Sodium hypochlorite had pooled at the leak location and subsequently run down the ESP apron, into the road, and into the storm drain located in the protected area fence. An estimate of approximately 300 gallons of spilled sodium hypochlorite was determined based on the time frame that the sodium hypochlorite was scheduled to start injecting into the 'A' spray pond and the time the leak was isolated. The leak was isolated on 4/25/2023 at approximately 2330. The leak was contained in the storm drain with the storm gates closed, therefore nothing was released offsite. The cleanup effort in progress includes diluting the sodium hypochlorite with domestic service water, collecting it into the storm drain, pumping it to a tank truck, and transporting it to the Palo Verde Water Resources Facility for neutralization. Condition Report 23-04519 was generated to document the leak. The Palo Verde Senior Environmental Scientist was notified and subsequently informed the Environmental Protection Agency (EPA) National Response Center (NRC#1365638) on 4/26/23 at 0005 in accordance with the 91DP-0EN03 Environmental Spill Response (local procedure). The NRC Senior Resident Inspector was also notified. No personnel were injured and no equipment was damaged as a result of the spill. The Palo Verde Fire Department was notified and the area was barricaded off to prevent personnel from entering the area during the cleanup effort. | Service water Spray Pond | |
| ENS 55205 | 22 April 2021 16:25:00 | 10 CFR 50.72(b)(2)(xi), Notification to Government Agency or News Release | Inadvertant Activation of Emergency Sirens | At 0925 Mountain Standard Time (MST) on April 22, 2021, Palo Verde Nuclear Generating Station staff received reports that Emergency Notification sirens were activated. Current information indicates that the inadvertent activation of the sirens was caused by an offsite agency during performance of a planned silent test that occurred at approximately 0916 MST. This event is reportable in accordance with 10 CFR 50.72(b)(2)(xi). All sirens remain functional, and the NRC Resident Inspectors have been notified of the issue. Additional notifications will be made as needed. | ||
| ENS 53702 | 29 October 2018 07:00:00 | 10 CFR 50.72(b)(2)(xi), Notification to Government Agency or News Release | Offsite Notification of Non- Work Related Fatality | The following event description is based on information currently available. If through subsequent reviews of this event additional information is identified that is pertinent to this event or alters the information being provided at this time, a follow-up notification will be made via the ENS or under the reporting requirements of 10CFR50.73. At approximately 03:30 MST on October 29, 2018, an Arizona Public Service Company (APS) employee developed a personal medical condition in the Owner Controlled Area outside of the Secured Owner Controlled Area at Palo Verde Generation Station (PVGS). PVGS Emergency Medical Technicians responded and transported the individual to an offsite emergency trauma center. Upon arrival at the trauma center, medical personnel declared the individual deceased at approximately 05:35 MST. The fatality was not work related and the individual was outside of the Radiological Controlled Area and no radioactive material or contamination was involved. No news release by APS is planned. Notifications were made to the Arizona Division of Occupational Safety and Health at 08:15 MST. The NRC Resident Inspectors have been notified. | ||
| ENS 51844 | 2 April 2016 05:29:00 | 10 CFR 50.72(b)(2)(xi), Notification to Government Agency or News Release | Offsite Notification Due to Sodium Hypochlorite Spill on Site | The following event description is based on information currently available. If through subsequent reviews of this event additional information is identified that is pertinent to this event or alters the information being provided at this time a follow-up notification will be made via the ENS or under the reporting requirements of 10CFR50.73. At approximately 2229 (MST) on April 1, 2016, Arizona Public Service Company completed an offsite notification to the Environmental Protection Agency's National Response Center to report a spill of approximately 8000 gallons of sodium hypochlorite (8% solution) in the vicinity of the Unit 3 cooling towers at the Palo Verde Nuclear Generating Station (PVNGS). Additional notifications were made to Arizona State and Maricopa County environmental authorities. The Unit 3 cooling towers are located in the Security Owner Controlled Area at PVNGS and are outside of the protected area. The leak, which resulted from a failed hose on the main hypochlorite distribution header, was stopped by closing a valve to isolate the header. The immediate area has been barricaded. The quantity released exceeded the Reportable Quantity for sodium hypochlorite (RQ of 100 pounds) and was therefore reported. There was no impact to the operation of the PVNGS units or personnel onsite or offsite. The NRC Senior Resident has been notified. | ||
| ENS 50984 | 15 April 2015 02:20:00 | 10 CFR 50.72(b)(2)(xi), Notification to Government Agency or News Release | Offsite Notification Due to Sodium Hydroxide Spill Onsite Exceeding Reportable Quantity | The following event description is based on information currently available. If through subsequent reviews of this event, additional information is identified that is pertinent to this event or alters the information being provided at this time, a follow-up notification will be made via the ENS or under the reporting requirements of 10CFR50.73. Arizona Public Service Co. made an offsite notification to the National Response Center regarding an approximately 3500 gallon caustic (8% sodium hydroxide) spill due to an improper valve lineup. The spill occurred at the Water Reclamation Facility (produces water for cooling towers and power plant and is located outside the Security Owner Controlled Area) in the area of the Fire Protection tanks (additional liquid was contained in a containment structure at the release location, and in a nearby concrete lined storm ditch on site). The release has been isolated, the immediate area has been barricaded. The quantity released exceeded the Reportable Quantity for sodium hydroxide (RQ of 1,000 pounds) and was therefore reported. Additionally, the state (Arizona) and county (Maricopa) have also been notified. There was no impact to the operation of the power units, aquifer or personnel onsite or offsite. The NRC Resident (Inspector) has been notified. | ||
| ENS 49482 | 29 October 2013 13:05:00 | 10 CFR 50.72(b)(2)(xi), Notification to Government Agency or News Release | Offsite Notification Due to Employee Fatality | At approximately 0530 MST on October 29, 2013, an Arizona Public Service Company (APS) employee developed a personal medical condition in the Owner Controlled Area prior to entering the Protected Area at the Palo Verde Nuclear Generation Station (PVNGS). PVNGS Emergency Medical Technicians responded and transported the individual to an offsite emergency trauma center. Upon arrival at the trauma center, medical personnel declared the individual deceased at 0650 (on 10/29/13). The fatality was not work related and the individual was outside of the Radiological Controlled Area. No radioactive material or contamination was involved. No news release by APS is planned. Notifications to the Arizona Division of Occupational Safety and Health, and the Maricopa County Sheriff's Office are planned. The NRC Resident Inspectors have been notified. | ||
| ENS 48347 | 26 September 2012 20:36:00 | 10 CFR 50.72(b)(2)(xi), Notification to Government Agency or News Release | Attempted Entry Onto the Site by an Illegal Alien with False Identification | This event is being reported as a newsworthy concern to the public under 10 CFR 50.72(b)(2)(xi). All times listed are approximate Mountain Standard Time. On September 26,2012, at 13:36 pm, Arizona Public Service (APS) was notified of the intention of Maricopa County Sheriff's Office (MCSO) to issue a press release regarding an attempted entry to the Palo Verde Nuclear Generating Station's (PVNGS) Security Owner Controlled Area (SOCA) by an individual with suspicious identification earlier this morning. An individual employed with a construction project sub-contractor arrived at the SOCA checkpoint and presented suspicious identification to PVNGS security officers to gain access to the site. The individual was not admitted through the checkpoint into the SOCA. MCSO was notified and placed the individual into custody. MCSO determined the identification was false and the individual was an undocumented immigrant. The individual did not enter nor was he previously granted access to the site's Protected Areas surrounding the three units and Independent Spent Fuel Storage Installation. No evidence of malicious intent has been identified. MCSO is investigating the incident. The station notified NRC Resident Inspectors and Region IV staff of the condition. APS does not intend at this time to issue a press release, but is responding to media inquiries. | ||
| ENS 47688 | 23 February 2012 01:45:00 | 10 CFR 50.72(b)(2)(xi), Notification to Government Agency or News Release | Suspicious Package Discovered on Site | The following event description is based on information currently available. If through subsequent reviews of this event additional information is identified that is pertinent to this event or alters the information being provided at this time a follow-up notification will be made via the ENS or under the reporting requirements of 10CFR50.73 At 1852 hours, Palo Verde Unit 1 was notified of a suspicious package located in the Owner Controlled Area outside the Protected Area. Maricopa County Sheriff's Office was contacted for assistance with a bomb disposal unit. Local media has become aware of this event and expressed interest by dispatching helicopters and television crews. There are no safety systems impacted by the package and operations personnel are not hampered in their ability to operate safety related equipment. There is no release of radioactivity to the environment as a result of this package and it has not adversely affected the safe operation of the plant or health and safety of the public. All three Palo Verde units are being maintained stable at approximately 100% power. The NRC Resident Inspector has been notified.
The Maricopa County Sherriff's Office bomb disposal unit responded and inspected the package. The suspicious package contained a granular absorbent material, similar to that used to clean liquid spills. The event was terminated at 23:02 AZ MST (on 2/22/12). The NRC Resident Inspector has been updated." Notified the R4DO (Deese). | ||
| ENS 47333 | 8 October 2011 23:19:00 | 10 CFR 50.72(b)(2)(xi), Notification to Government Agency or News Release 10 CFR 50.72(a)(1)(i), Emergency Class Declaration | Notification of Unusual Event Due to Severe Electrical Fault in Rcp Junction Box | Reactor Coolant Pump 2A tripped at approximately 1535 MST, resulting in numerous simultaneous electrical distribution alarms. A walkdown of containment was performed and at 1609 MST it was determined that a junction box, supplying power to the 2A Reactor Coolant Pump, had failed, resulting in the pump tripping on overcurrent protection and an 86 lockout. The plant was operating in forced circulation and had one train of shutdown cooling in service. As a result, an Emergency Classification of HU2.2, Explosion was declared due to the junction box failure and noise that had been heard in containment. The plant is currently stable with one train of shutdown cooling in service, the opposite train of shutdown cooling is available to be placed in service. The Unit 1 Reactor Coolant System is currently at 160 degrees Fahrenheit and 375 psia with the 1A Reactor coolant pump in service for forced circulation. The event did not result in the release of radioactivity to the environment and did not adversely affect the safe operation of the plant or health and safety of the public. The NRC Resident Inspector has been notified. The licensee has notified appropriate state and local agencies.
The Notification of Unusual Event at Palo Verde Unit 1 was terminated at 1916 MST on 10/8/2011. The termination was based on conducting inspections which did not reveal any additional damage or plant impact as a result of this event. Unit 1 remains stable in Mode 5 with RCPs 1A and 1B in service along with one train of RHR in service. The licensee notified the NRC Resident Inspector and appropriate state and local agencies. Notified R1DO (Gray), NRR EO (Hiland), IRD (Grant), DHS (Flinter), and FEMA (Castro). | Reactor Coolant System Shutdown Cooling | |
| ENS 47050 | 14 July 2011 21:11:00 | 10 CFR 50.72(b)(2)(xi), Notification to Government Agency or News Release | News Release Regarding Arrest of Illegal Immigrant Working at Palo Verde | The following event description is based on information currently available. If through subsequent reviews of this event, additional information is identified that is pertinent to this event or alters the information being provided at this time, a follow-up notification will be made via the ENS or under the reporting requirements of 10CFR50.73. This event is being reported as a newsworthy concern to the public under 10 CFR 50.72(b)(2)(xi). Palo Verde Nuclear Generating Station (PVNGS) was notified that the Maricopa County Sheriff's Office (MCSO) issued a news release at 1411 on July 14, 2011, regarding entrance to the PVNGS site property by an individual who MCSO alleged to be an undocumented immigrant. The individual had entered Palo Verde's Security Owner Controlled Area on July 13, 2011, but was not granted access to the site's Protected Areas surrounding the three units and Independent Spent Fuel Storage Installation. PVNGS Security contacted MCSO to validate the identification card furnished by the individual at the Security Owner Controlled Area. MCSO determined the identification card to be suspicious, responded to the site, detained the individual, and transported him off-site for questioning. The station notified NRC Resident Inspectors and Region IV staff of the condition on July 13, 2011. Arizona Public Service is planning to issue a news release and is responding to media inquiries regarding the matter. | ||
| ENS 46634 | 22 February 2011 16:09:00 | 10 CFR 50.72(b)(2)(xi), Notification to Government Agency or News Release | Offsite Notification Due to Loss of Potable Water Supply | Arizona Public Service Co. made an offsite notification to the Maricopa County Environmental Services Division at 0909 MST on February 22, 2011, to report a loss of power to the Palo Verde Nuclear Generating Station drinking water supply pumps which resulted in the depressurization of the site domestic water supply header. The pumps were out of service on February 21, 2011, between the hours of 2001 and 2300 MST. Full service has been restored. The loss of power was related to the loss of Startup Transformer A-E-NAN-X02 as reported in ENS #46633 at 0023 on February 21, 2011. The NRC Resident Inspectors have been notified. | ||
| ENS 44401 | 8 August 2008 22:20:00 | 10 CFR 50.72(b)(2)(xi), Notification to Government Agency or News Release | Offsite Notification to Maricopa County Environmental Services | Arizona Public Service Co. made an offsite notification to Maricopa County Environmental Services at 1520 MST on 8/8/08 to report a loss of power to the Palo Verde Nuclear Generating Station drinking water supply pumps. The pumps were out of service on 8/8/08 between the hours of 0532 and 0620 MST. Full service has been restored. The licensee notified the NRC Resident Inspector. | ||
| ENS 43876 | 31 December 2007 15:40:00 | 10 CFR 50.72(b)(2)(xi), Notification to Government Agency or News Release | Death of an Employee Outside the Protected Area | The following event description is based on information currently available. If through subsequent reviews of this event, additional information is identified that is pertinent to this event or alters the information being provided at this time, a follow-up notification will be made via the ENS or under the reporting requirements of 10CFR50.73. At approximately 06:40 MST on December 31, 2007, at the water reclamation facility for the Palo Verde Nuclear Generating Station, an employee died. The death was not related to activities impacting or related to the safety of the public or other onsite personnel. Specifically, an individual collapsed and was promptly examined by a Palo Verde Emergency Medical Technician (EMT). An air evacuation was ordered however, prior to air evacuation the individual expired. The death does not appear to be work-related nor the result of an accident. The individual was outside of the Radiological Controlled Area and no radioactive material or contamination was involved. Palo Verde has not observed any heightened public or media concern as a result of the death. Since the death is apparently unrelated to Palo Verde's industrial or radiological health and safety, no news release is planned. The individual's name has not yet been released, pending notification of next-of-kin. The Arizona Division of Occupational Safety and Health was notified of the death at 0840 MST. The Maricopa County Sheriff's Office is conducting a routine investigation into the death." The licensee notified the NRC Resident Inspector. | ||
| ENS 43764 | 2 November 2007 14:44:00 | 10 CFR 50.72(b)(2)(xi), Notification to Government Agency or News Release 10 CFR 50.72(a)(1)(i), Emergency Class Declaration | Suspicious Explosive Device Discovered in Vehicle at Oca Access Checkpoint | On November 2, 2007 at 0744 (MST), Palo Verde Nuclear Generating Station Units 1, 2 and 3 declared a Notification of an Unusual Event as specified in the Emergency Plan. The basis for the Emergency Class declaration was detection of a credible threat: an explosive device was detected during a vehicle search at the site access check point. The site has entered its Deliberate Acts procedure. The device was discovered in a contract employee's vehicle at 0525 MST. It was confirmed to be an explosive device at 0730 MST by the Maricopa County Sheriff's Office (MCSO). The explosive device was removed from the site by MCSO and Federal Bureau of Investigation (FBI) at 0852. The individual driving the vehicle has been detained by MCSO. No other individuals were in the vehicle at the time. Palo Verde Unit 1 is in Mode 2 at approximately 2% power. Unit 2 is in Mode 1 at 100% power. Unit 3 is defueled undergoing steam generator replacement. No reactor protection system or engineered safety feature system actuations have occurred and none are required. No major structures, systems, or components are inoperable impacting the continued safe operation of the units. Plans are to continue Mode 2 operations in Unit 1 and Mode 1 full power operation in Unit 2. Further investigation is ongoing in cooperation with MCSO and the FBI. Security is conducting searches of the site. No additional concerns have been identified at this time. The security event has not resulted in any challenges to the fission product barrier or result in any releases of radioactive materials. There were no adverse safety consequences or implications as a result of the security event declaration. A news release was made at 11:10 a.m. The licensee notified the NRC Resident Inspector.
At 1447 MST site security posture has changed from Code Red to Code Yellow Heightened Awareness, and at 1504 MST licensee exited the Unusual Event,. The licensee has notified the NRC Resident Inspector, state and local agencies, and will be issuing a press release this evening. Notifications were given to the following: R4 (Art Howell), R4DO(Powers), NRR EO (Bateman), IRD Manager (Blount), ILTAB (Sandler), DHS (York), FEMA (Dunker), DOE (Wyatt), FBI-SIOC (Curry), HHS (White), USDA (Phillip).
The licensee downgraded the security posture at the site from Code Yellow Heightened Awareness to Code Yellow. The licensee notified the NRC Resident Inspector. Notified R4DO (Powers) and ILTAB (Sandler).
Arizona Public Service Company (APS) is retracting security-related Event Notification #43764 and notification of unusual event (NUE) reported on November 2, 2007. Based upon investigations performed by the Federal Bureau of Investigation (FBI), Maricopa County Sheriff's Office (MCSO) and Palo Verde Security department, APS has determined that there was no explicit nor credible threatened action as described in 10 CFR 73.71, Appendix G, Paragraph I. These investigations revealed that the previously reported explosive device was placed in the owner's truck bed without his knowledge. Therefore, there is no reason to believe that a person has committed or caused, or attempted to commit or cause, or has made a credible threat to commit or cause: theft or unlawful diversion of special nuclear material; or significant physical damage to a power reactor; or interruption of normal operation of a licensed nuclear power reactor. The licensee notified the NRC Resident Inspector. R4DO (Farnholtz) has been notified and an e-mail sent to ILTAB and the 73.71 group. | Steam Generator Reactor Protection System | |
| ENS 42381 | 2 March 2006 21:30:00 | 10 CFR 50.72(b)(2)(xi), Notification to Government Agency or News Release | Offsite Notification | The following event description is based on information currently available. If through subsequent reviews of this event, additional information is identified that is pertinent to this event or alters the information being provided at this time, a follow-up notification will be made via the ENS. This is a report of a situation, related to the protection of the environment, for which a notification to another government agency has been or will be made, as described in 10CFR50.72(b)(2)(xi). Specifically, the Palo Verde Nuclear Generating Station (PVNGS) notified the Arizona Department of Environmental Quality (ADEQ) of the possibility of a discharge of non-hazardous material that has the potential to cause groundwater limits to be exceeded At Palo Verde Unit 3, water was observed in a concrete pipe vault that was abutted against soil. The source of the water appeared to becoming from seals around the pipes and originating from the ground behind the pipe chase. The area behind the pipe chase contains a series of pipes buried in a layer of compacted soil. In order to characterize the water and identify its source, a pothole, approximately 13 feet deep and reinforced with a perforated drain pipe was dug in the radiological controlled area yard so that a sample of the water could be obtained. Initial results from the unit laboratory indicated the presence of tritium. A confirmatory sample was collected and analyzed by the State certified laboratory at Palo Verde that confirmed the presence of tritium at a concentration of approximately 7.14 x 10 -5 microCurie per milliliter. The Aquifer Protection Permit Aquifer Quality Limit for tritium is 2.00 x 10 -5 microCurie per milliliter. At this time we are working to identify the source. We currently have no evidence that the water has contaminated any aquifer but are continuing with our investigation. Palo Verde's ground-water monitoring program - in place since the unit operations began - has validated that no tritium has been present in any wells or aquifers in any quarterly samples. PVNGS has just finished collecting its quarterly monitoring samples. Analyzed samples have no indication of tritium. The remaining samples will be completed next week. No Technical Specification effluent limits have been exceeded. No Offsite Dose Calculation Manual (ODCM) effluent limits have been exceeded. No federal effluent limits have been exceeded. Palo Verde has not identified any health or safety risk to the public or onsite personnel. No source of leakage or release path has been identified, therefore no release rate or total quantity released has been quantified. Unit 3 is operating at approximately 100% rated thermal power at normal operating temperature and pressure. This information is also being reported to the Arizona Radiation Regulatory Agency. The licensee notified the NRC Resident Inspector. | ||
| ENS 42101 | 31 October 2005 19:02:00 | 10 CFR 50.72(b)(2)(xi), Notification to Government Agency or News Release | Media Interest | The following event description is based on information currently available. If through subsequent reviews of this event, additional information is identified that is pertinent to this event or alters the information being provided at this time, a follow-up notification will be made via the ENS or under the reporting requirements of 10CFR50.73. On October 31, 2005, at approximately 12:02 PM Mountain Standard Time (MST) the Palo Verde Nuclear Generating Station was informed of a request to conduct a media interview with a clearinghouse that provides newsworthy input to local media regarding an emergency preparedness exercise to commence tomorrow. No press release is planned by Palo Verde, but the interview is indication of media interest. The State of Arizona and Maricopa County will be performing an ingestion pathway emergency preparedness exercise on November 1, 2005 through November 3, 2005. The exercise will be evaluated by the Federal Emergency Management Agency (FEMA). Although this exercise will involve significant participation by State and County agencies, Palo Verde participation is expected to be limited to a small control cell of personnel to simulate communication with the State and County. There has been some media interest. There have been no official press releases posted by Maricopa County or the State of Arizona, although the Governor's calendar for November 1, 2005 indicates that the Honorable Janet Napolitano will participate. Resident NRC inspectors are not expected to participate in this exercise, but Palo Verde understands that two NRC Region IV personnel (Messrs. T. Andrews and W. Maier) are expected to support FEMA evaluation of the exercise. Palo Verde Unit 1 is in a refueling outage with all fuel assemblies offloaded to the spent fuel pool. Units 2 and 3 are operating in Mode 1 at approximately 100% power, at normal operating temperature and pressure. The licensee notified the NRC Resident Inspector. | ||
| ENS 41960 | 29 August 2005 17:30:00 | 10 CFR 50.72(b)(2)(xi), Notification to Government Agency or News Release | Off Site Notifications Due to Loss of Inoperable Emergency Evacuation Siren | On August 29, 2005 at approximately 10:30 Mountain Standard Time (MST), the Palo Verde Emergency Preparedness Department identified an inoperable single siren (#18). The siren was vandalized by stealing the internal battery. The affected siren is estimated to impact approximately 131 members of population in the emergency planning zone (EPZ) within 5 miles. This call is being placed due to the relatively large segment of the population affected and the uncertainty of the length of time that will be needed to restore the siren to operable condition. The Palo Verde Emergency Plan (section 6.6.2.1) has a contingency for dispatching Maricopa County Sheriff's Office (MCSO) vehicles with loud speakers to alert persons within the affected area's) when sirens are inoperable. Maricopa County and State agencies have been informed to implement the MCSO notification if a need arises. There are no events in progress that require siren operation. The NRC Resident Inspector has been notified | ||
| ENS 41941 | 23 August 2005 20:49:00 | 10 CFR 50.72(b)(2)(xi), Notification to Government Agency or News Release 10 CFR 50.72(b)(3)(xiii), Loss of Emergency Preparedness | Two Emergency Sirens Inoperable | The following event description is based on information currently available. If through subsequent reviews of this event, additional information is identified that is pertinent to this event or alters the information being provided at this time, a follow-up notification will be made via the ENS or under the reporting requirements of 10CFR50.73. On August 23, 2005 at approximately 13:49 Mountain Standard Time (MST), the Palo Verde Emergency Preparedness Department identified a siren (#42) inoperable due to a failed battery charger. At approximately 14:00 a faxed notice was found indicating siren #15 had failed its response check. The fax was sent approximately at 07:00 but was not noticed till later since out of service siren notifications are generally made via phone or e-mail. Upon investigation, siren #15 was found inoperable due to a circuit board failure. Siren #15 is estimated to impact approximately 144 members of population in the emergency planning zone (EPZ) within 5 miles, and siren #42 is estimated to impact 496 members of the population in the EPZ, beyond 5 miles but within 10 miles. Palo Verde's reporting criterion is a loss of capability to inform greater than 5% of the population within 5 miles and 10% of the population beyond 5 miles but within 10 miles. This call is being placed due to the relatively large segment of the population affected and the uncertainty of the length of time that will be needed to restore the siren to operable condition. The Palo Verde Emergency Plan (section 6.6.2.1) has a contingency for dispatching Maricopa County Sheriff's Office (MCSO) vehicles with loud speakers to alert persons within the affected area(s) when sirens are inoperable. There are no events in progress that require siren operation. The NRC Resident Inspector has been notified of the siren failure and this ENS call. | ||
| ENS 41912 | 11 August 2005 15:45:00 | 10 CFR 50.72(b)(2)(xi), Notification to Government Agency or News Release 10 CFR 50.72(b)(3)(xiii), Loss of Emergency Preparedness | One Emergency Preparedness Siren Out of Service | On August 11, 2005 at approximately 08:45 Mountain Standard Time (MST), the Palo Verde Emergency Preparedness Department identified an inoperable single siren (#15). While reviewing the siren monitoring computer log, an Information Services Technician received a 'no response' signal on siren #15. Upon investigation, siren #15 was found inoperable. The siren was vandalized by destroying the siren controller case and stealing the internal battery. The affected siren is estimated to impact approximately 496 members of population in the emergency planning zone (EPZ) beyond 5 miles but within 10 miles. Palo Verde's reporting criterion is a loss of capability to inform greater than 10% of the population beyond 5 miles but within 10 miles. This call is being placed due to the relatively large segment of the population affected and the uncertainty of the length of time that will be needed to restore the siren to operable condition. The Palo Verde Emergency Plan (section 6.6.2.1) has a contingency for dispatching Maricopa County Sheriff's Office (MCSO) vehicles with loud speakers to alert persons within the affected area(s) when sirens are inoperable. The County was informed at 09:05 MST to implement the MCSO notification if a need arises. There are no events in progress that require siren operation. The licensee notified the NRC Resident Inspector. | ||
| ENS 41810 | 29 June 2005 11:43:00 | 10 CFR 50.72(b)(2)(xi), Notification to Government Agency or News Release 10 CFR 50.72(b)(3)(xiii), Loss of Emergency Preparedness | Evacuation Siren Inoperable | The following event description is based on information currently available. If through subsequent reviews of this event, additional information is identified that is pertinent to this event or alters the information being provided at this time, a follow-up notification will be made via the ENS or under the reporting requirements of 10CFR50.73. On June 29, 2005 at approximately 08:55 Mountain Standard Time (MST), the Palo Verde Emergency Preparedness Program Manager was notified of an inoperable single siren #36. An alarm indicates that the inoperability started at 04:43 AM MST. The siren was vandalized by destroying the battery case and stealing the internal battery. The affected siren is estimated to impact approximately 215 members of population (10.1 %) in the emergency planning zone (EPZ) within 5 miles. Palo Verde's reporting criterion is a loss of capability to inform greater than 5% of the population within 5 miles (or 10% within 5 to 10 miles) for greater than 1 hour. This call is being placed due to the relatively large segment of the population affected and the uncertainty of the length of time that will be needed to restore the siren to operable condition. The Palo Verde Emergency Plan (section 6.6.2.1) has a contingency for dispatching Maricopa County Sheriffs Office (MCSO) vehicles with loud speakers to alert persons within the affected area(s) when sirens are inoperable. The County was informed at 09:25 AM MST to implement the MCSO notification if a need arises. There are no events in progress that require siren operation. The NRC Resident Inspector has been notified of the siren failure and this ENS call. | ||
| ENS 41497 | 16 March 2005 01:51:00 | 10 CFR 50.72(b)(2)(xi), Notification to Government Agency or News Release | Offsite Notifications Due to Caustic Spill | The following information was provided by the licensee via facsimile (licensee text in quotes): The following event description is based on information currently available. If through subsequent reviews of this event, additional information is identified that is pertinent to this event or alters the information being provided at this time, a follow-up notification will be made via the ENS or under the reporting requirements of 10CFR50.73. On March 15, 2005 at approximately 18:51 Mountain Standard Time (MST), the Palo Verde Nuclear Generating Station informed another government agency, the EPA/DOT National Response Center, of a caustic spill, related to the protection of the environment. Notification was also made to the Arizona Department of Environmental Quality and the Arizona Department of Public Safety (State Police). No news release is planned or expected. A commercial tanker truck was transferring caustic sodium hydroxide at Unit 1 when a drip was observed from the transfer hose at approximately 16:54 MST. The spill was limited to approximately one quart outside of the spill containment berm. The evolution was terminated and the tanker truck was driven out of the Protected Area. A drip trail was later discovered at approximately 18:00 along the path of the truck out of the Protected Area, including a puddle of approximately 3 gallons in the sally port (access point). The truck was returning to Phoenix, AZ. The spill quantity on-site is not estimated to have approached a reportable quantity (1,000 pounds), but due to the evidence that the truck was leaking while in transit to Phoenix, the Palo Verde Hazardous Materials Emergency Coordinator conservatively elected to make the government notifications. Additionally, Palo Verde notified the trucking company which ultimately located the truck upon its return to the company yard. No leak existed at that time, suggesting the leakage was limited to the caustic that remained in the truck's discharge pipe after the transfer was stopped. There was no impact to control room habitability and no safety systems, including essential ventilation, were actuated or required. The spill did not hamper site personnel in the performance of duties necessary for the safe operation of the nuclear power plant. The NRC Resident inspector was notified of the chemical spill and this ENS notification. | ||
| ENS 41268 | 17 December 2004 17:53:00 | 10 CFR 50.72(b)(2)(xi), Notification to Government Agency or News Release | Offsite Notifications Made Due to Spill of Approximately 1400 Pounds of Sulfuric Acid | On 12/17/2004 at approximately 10:53 MST, Palo Verde Nuclear Generating Station (PVNGS) notified the Department of Transportation/US. Coast Guard National Response Center of a sulfuric acid spill to the ground at the Water Reclamation Facility. The source of cooling water for PVNGS is treated sewage effluent. The effluent is conveyed to the site through approximately 35 miles of pipeline, and treated in the onsite water reclamation facility to meet plant water quality requirements. The acid spill has no impact to the radiological health and safety of the workers or the public. The spill is estimated at 1400 pounds. The reportable quantity is 1000 pounds. The sulfuric acid is classified as a CERCLA Hazardous Substance and EPCRA Extremely Hazardous Substance. The release has been isolated and the apparent cause is a leak in an underground section of pipe. There were no injuries and no known or anticipated acute or chronic health risks. The National Response Center report number is 744571. The Arizona Department of Environmental Quality was also informed at 10:51 MST. There was no impact to the three generating units from the spill at the Water Reclamation Facility which is located at a separate part of the Owner Controller Area. All 3 PVNGS Units are operating at approximately 100% in Mode 1. The NRC Resident has been notified of the event and this notification. | ||
| ENS 40816 | 14 June 2004 14:44:00 | 10 CFR 50.72(b)(2)(xi), Notification to Government Agency or News Release 10 CFR 50.72(b)(2)(iv)(B), RPS System Actuation 10 CFR 50.72(a)(1)(i), Emergency Class Declaration 10 CFR 50.72(b)(3)(iv)(A), System Actuation | Unusual Event Due to Reactor Trip Due to Loss of Off Site Power | On June 14, 2004, at approximately 07:44 Mountain Standard Time (MST) all three units at the Palo Verde Nuclear Generating Station experienced automatic reactor trips coincident with a grid disturbance and loss of offsite power in the Palo Verde Switchyard. Unit 3 declared a NOTIFICATION OF UNUSUAL EVENT at 07:53 MST due to a loss of offsite power to essential buses for greater than 15 minutes. The NOTIFICATION OF UNUSUAL EVENT was terminated at 12:07 MST. Unit 3 received an automatic Main Steam Isolation System ESF actuation. Due to the loss of offsite power, the Emergency Plan Technical Support Center (TSC) was unavailable. The Unit 2 Satellite TSC was to be staffed by the Emergency Response Organization in response to the loss of assessment capability. Power to the TSC has since been restored. The unit was at normal operating temperature and pressure prior to the trip. All CEAs inserted fully into the reactor cores. All Emergency Diesel Generators (EDGs) (2 per unit) associated with the unit started as expected in response to the loss of offsite power to their safety buses. The offsite power grid had several perturbations for approximately one hour following the event but has been stable since. LCO 3.8.1, AC Sources - Operating, was entered as a result of this event. Heat removal is to atmosphere via atmospheric dump valves in natural circulation. Main steam safety valves may have lifted for a brief time. Restoration of forced reactor coolant circulation is pending assurance that the offsite power grid can reliably support the load. No major equipment was inoperable prior to the event that contributed to the event. The Unit is stable at normal operating temperature and pressure in Mode 3. The event did not result in any challenges to fission product barriers and there were no adverse safety consequences as a result of this event. The event did not adversely affect the safe operation of the plant NRC Resident Inspector was notified. FBI Jeff Muller and Mr. Rosales (Mexican National Commission of Nuclear Safety and Safeguards (CNSNS)) were notified.
Notified Reg 4 RDO (Graves), NRR (Bateman), DHS (Lee), FEMA (Canupp), DOE (Sal Moroni), EPA (Stalcup), EPA (Crews), HSS (Davidson), and Mexico (Rosales) Note: see related events 40815 , 40814 and 40818 | Emergency Diesel Generator Main Steam Safety Valve Main Steam | |
| ENS 40815 | 14 June 2004 14:44:00 | 10 CFR 50.72(b)(2)(xi), Notification to Government Agency or News Release 10 CFR 50.72(b)(2)(iv)(B), RPS System Actuation 10 CFR 50.72(a)(1)(i), Emergency Class Declaration 10 CFR 50.72(b)(3)(iv)(A), System Actuation | Unusual Event Declared Due to Reactor Trip Due to Loss of Off Site Power | On June 14, 2004, at approximately 07:44 Mountain Standard Time (MST) all three units at the Palo Verde Nuclear Generating Station experienced automatic reactor trips coincident with a grid disturbance and loss of offsite power in the Palo Verde Switchyard. Unit 1 declared a NOTIFICATION OF UNUSUAL EVENT at 07:53 MST due to a loss of offsite power to essential buses for greater than 15 minutes. The NOTIFICATION OF UNUSUAL EVENT was terminated at 12:07 MST. Unit 1 manually initiated a Main Steam Isolation System ESF actuation by procedure. Due to the loss of offsite power, the Emergency Plan Technical Support Center (TSC) was unavailable. The Unit 2 Satellite TSC was to be staffed by the Emergency Response Organization in response to the loss of assessment capability. Power to the TSC has since been restored. The unit was at normal operating temperature and pressure prior to the trip. All CEAs inserted fully into the reactor cores. All Emergency Diesel Generators (EDGs) (2 per unit) associated with the unit started as expected in response to the loss of offsite power to their safety buses. The offsite power grid had several perturbations for approximately one hour following the event but has been stable since. LCO 3.8.1, AC Sources - Operating, was entered as a result of this event. Heat removal is to atmosphere via atmospheric dump valves in natural circulation. Main steam safety valves may have lifted for a brief time. Restoration of forced reactor coolant circulation is pending assurance that the offsite power grid can reliably support the load. No major equipment was inoperable prior to the event that contributed to the event. The Unit is stable at normal operating temperature and pressure in Mode 3. The event did not result in any challenges to fission product barriers and there were no adverse safety consequences as a result of this event. The event did not adversely affect the safe operation of the plant NRC Resident Inspector was notified. FBI Jeff Muller and Mr. Rosales (Mexican National Commission of Nuclear Safety and Safeguards (CNSNS)) were notified.
Notified Reg 4 RDO (Graves), NRR (Bateman), DHS (Lee), FEMA (Canupp), DOE (Sal Moroni), EPA (Stalcup), EPA (Crews), HSS (Davidson), and Mexico (Rosales) Note: see related events # 40814, 40816 and 40818 | Emergency Diesel Generator Main Steam Safety Valve Main Steam | |
| ENS 40814 | 14 June 2004 14:44:00 | 10 CFR 50.72(b)(2)(xi), Notification to Government Agency or News Release 10 CFR 50.72(b)(2)(iv)(B), RPS System Actuation 10 CFR 50.72(a)(1)(i), Emergency Class Declaration 10 CFR 50.72(b)(3)(iv)(A), System Actuation | Alert Declared - Reactor Trip Due to Loss of Off Site Power | On June 14, 2004, at approximately 07:44 Mountain Standard Time (MST) all three units at the Palo Verde Nuclear Generating Station experienced automatic reactor trips coincident with a grid disturbance and loss of offsite power in the Palo Verde Switchyard. Unit 2 declared an ALERT Emergency Plan classification at approximately 07:54 due to a loss of AC power to essential buses reduced to a single power source for greater than 15 minutes such that any additional single failure would result in a station blackout. Subsequently, at 09:51 Unit 2 downgraded the Emergency Plan classification to a NOTIFICATION OF UNUSUAL EVENT when AC power was restored from a single essential bus to both essential buses. Units 1 and 3 declared a NOTIFICATION OF UNUSUAL EVENT at 07:53 MST due to a loss of offsite power to essential buses for greater than 15 minutes. The NOTIFICATION OF UNUSUAL EVENT was terminated for all 3 units at 12:07 MST. Unit 1 and 2 manually initiated a Main Steam Isolation System ESF actuation by procedure. Unit 3 received an automatic Main Steam Isolation System ESF actuation. Due to the loss of offsite power, the Emergency Plan Technical Support Center (TSC) was unavailable. The Unit 2 Satellite TSC was to be staffed by the Emergency Response Organization in response to the loss of assessment capability. Power to the TSC has since been restored. The Emergency Plan ALERT declaration includes staffing of the Joint Emergency New Center to address expected media interest. All three units were at normal operating temperature and pressure prior to the trip. All CEAs inserted fully into the reactor cores. All Emergency Diesel Generators (EDGs) (2 per unit) associated with each of the 3 units started as expected in response to the loss of offsite power to their safety buses. Unit 2's train "A" EDG started, but did not indicate volts or amps and was manually shutdown. The offsite power grid had several perturbations for approximately one hour following the event but has been stable since. LCO 3.8.1, AC Sources - Operating, was entered in each unit as a result of this event. Heat removal is to atmosphere via atmospheric dump valves in natural circulation. Main steam safety valves may have lifted for a brief time. Restoration of forced reactor coolant circulation is pending assurance that the offsite power grid can reliably support the load. No major equipment was inoperable prior to the event that contributed to the event. All 3 units are stable at normal operating temperature and pressure in Mode 3. The event did not result in any challenges to fission product barriers and there were no adverse safety consequences as a result of this event. The event did not adversely affect the safe operation of the plant NRC Resident Inspector was notified. FBI Jeff Muller and Mr. Rosales (Mexican National Commission of Nuclear Safety and Safeguards (CNSNS)) were notified.
Notified Reg 4 RDO (Graves), NRR (Bateman), DHS (Lee), FEMA (Canupp), DOE (Sal Moroni), EPA (Stalcup), EPA (Crews), HSS (Davidson), and Mexico (Rosales) NOTE: See events 40815, 40816 and 40818 | Emergency Diesel Generator Main Steam Safety Valve Main Steam | |
| ENS 40680 | 17 April 2004 14:26:00 | 10 CFR 50.72(b)(2)(xi), Notification to Government Agency or News Release | Offsite Notification - Small Fire at Palo Verde 1: Two Employees Injured, No Plant Equipment Damage | On Saturday, April 17, 2004, at approximately 07:26 (MST), a fire in the Palo Verde Nuclear Generating Station Unit 1 turbine building resulted in two injuries due to burns. Both individuals were transported offsite for treatment. One of the two was airlifted with suspected second degree burns. Neither involved any radioactive contamination. No press release is planned, but media attention has already been observed in response to media monitoring communications on local police/fire scanners. Calls have been received from several TV stations. One local station broadcast the fire and injuries at approximately 09:40 (MST). Palo Verde Unit 1 is shutdown and defueled in its eleventh refueling outage. The fire was associated with pre-heating for welding in the turbine building. It is suspected that solvent vapor in the vicinity of the pre-heating activity may have flashed. The fire was extinguished in less than 15 minutes and no emergency plan classification was declared or required as a result of the fire. The NRC Resident Inspector has been notified of the event and this ENS notification. The fire occurred near the Main Feed Pump Turbine Alpha, which was dismantled at the time. There appears to be no physical damage to any plant equipment, although some nearby cleaning rags were partially burned.
1) Both workers received facial burns. One was treated and released at approximately 11:00 MST on Saturday, April 17, 2004. The other was released during the morning of Sunday, April 18, 2004. 2) There was no equipment damage as a result of the fire. The apparent cause of the fire in the "A" main feed pump turbine lower shell was residual isopropyl alcohol in a drain hole. The alcohol is used to clean solvent residue to have the turbine shell oil-free for NDE (non-destructive examination) purposes. The NRC Resident Inspector has been notified of this ENS update. Notified NRC Region 4 Duty Officer (D. Powers) | ||
| ENS 40561 | 1 March 2004 23:49:00 | 10 CFR 50.72(b)(2)(xi), Notification to Government Agency or News Release | Press Release Regarding Boron Residue | The license provided the following via facsimile: "This ENS notification is to inform the agency of a news release that was issued 03/01/04 at 1649 Mountain Standard Time (MST) regarding the shutdown of Palo Verde Nuclear Generating Station Unit 3 and discovery of boron residue on a pressurizer heater sleeve which was reported to the Headquarters Operations Center in ENS ID 40556. The unit has been cooled down to Mode 5 in preparation of maintenance to repair the pressurizer heater sleeve. Current plant conditions are approximately 125 degrees F and 35 psia. The NRC Resident Inspector has been notified of this ENS call. | ||
| ENS 40533 | 20 February 2004 17:33:00 | 10 CFR 50.72(b)(2)(xi), Notification to Government Agency or News Release | Offsite Notification Due to a Press Release Concerning the Unit 2 Shutdown | The following event description is based on information currently available. If through subsequent reviews of this event, additional information is identified that is pertinent to this event or alters the Information being provided at this time, a follow-up notification will be made via the ENS or under the reporting requirements of 10CFR50.73. This ENS notification is to inform the agency of the shutdown of Palo Verde Nuclear Generating Station Unit 2, due to increasing primary to secondary leakage, for which a news release has been issued. Unit 2 was shutdown to Mode 3 on February 19, 2004 at 18:28 Mountain Standard Time (MST) following detection of increased primary to secondary leakage at approximately 15:22 MST. The leakage was less than the Technical Specification 3.4.14(d) limit of 150 gallons per day through any one SG. Steam generator #1 was isolated at approximately 18:40 MST. The unit has been cooled down to Mode 5 in preparation of maintenance to repair the steam generator. Current plant conditions are approximately 160 degrees F and 350 psia. The decision to issue a press release was made at approximately 09:00 MST on February 20, 2004. The press release was issued at approximately 10:33 MST. The NRC Resident Inspector has been notified of this ENS call. This is the 1st cycle using these Steam Generators which were replaced in 2003. The licensee indicated that the change in in primary to secondary leakage was a step increase but was unable to accurately quantify the amount since it was less than 20 gallons per day. | Steam Generator |