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| Start date | Reporting criterion | Title | Event description | System | LER | |
|---|---|---|---|---|---|---|
| ENS 52957 | 9 September 2017 15:09:00 | Other Unspec Reqmnt | Hurricane Warning Issued Affecting Site within 36 Hours | Crystal River Unit 3 is currently undergoing decommissioning and is permanently shut down. The licensee entered their adverse weather procedure EM-220D based on a Hurricane Warning affecting the site within 36 hours. All applicable sections of EM-220D are complete or in progress. No fuel movement activities are in progress. All equipment including Emergency Diesel Generators (EDGS) is available to perform required spent fuel cooling. The licensee will inform the NRC Region I Office. | Emergency Diesel Generator | |
| ENS 46722 | 4 April 2011 04:00:00 | Other Unspec Reqmnt | Press Release Concerning Additional Containment Delamination | Progress Energy Florida, Inc. has notified the Florida Public Service Commission (FPSC) that the Crystal River Unit 3 (CR-3) Nuclear Plant will remain out of service while the company conducts a thorough engineering analysis and review of a new delamination. Options to return the plant to service will be analyzed after the report is complete. The company cannot estimate a return to service date for CR-3 at this time. In mid-March, final retensioning of tendons within the CR-3 containment building was suspended while engineers investigated evidence of an additional delamination (or separation) resulting from the tendon retensioning work. The initial damage occurred in late 2009 in the concrete at the periphery of the containment building while creating an opening in the structure to facilitate the replacement of the steam generators inside. The unit was already shut down for refueling and maintenance at the time the damage was found. The plant has been shut down since September 2009 and there continues to be no threat to public health and safety. Progress Energy continues to coordinate repair and restart plans with Nuclear Regulatory Commission officials. The licensee notified the NRC Resident Inspector. | Steam Generator | |
| ENS 46673 | 14 March 2011 18:11:00 | Other Unspec Reqmnt | Additional Delaminated Containment Concrete Discovered | Crystal River Unit 3 is currently shutdown. Final tendon re-tensioning activities were being conducted following repair of delaminated (separated) concrete at the periphery of the containment wall. At approximately 1311 (EDT) on March 14, 2011, an indication was received from acoustic monitoring instrumentation located on the containment wall outside the previously repaired area. Re-tensioning activities were stopped and Plant Operations verified that there were no changes in plant parameters. Non-destructive examinations were initiated and preliminary indications are that there is delaminated concrete in the area identified by the acoustic monitoring. An assessment concluded that the containment continues to maintain the closure-pressure retaining capability required for Mode 5. There continues to be no threat to the public heath and safety. Delaminated concrete at the periphery of the containment wall was created in late 2009 during the process of creating an opening in the structure to remove and replace the steam generators inside (Reference Event Report 45416). The unit was already shut down for refueling and maintenance at the time the damage was found and has remained shut down. The extent of newly discovered delaminated has not yet been determined. The licensee plans to make a press release. The licensee has notified the NRC Resident Inspector and the Florida Public Service Commission. | Steam Generator | |
| ENS 45416 | 7 October 2009 23:30:00 | Other Unspec Reqmnt | Discovery of a Containment Separation | Crystal River Unit 3 is currently shutdown for a planned refueling and steam generator replacement outage. During containment building concrete removal activities to create a construction opening to support steam generator replacement, a separation in the concrete was discovered in the vicinity of the construction opening near the periphery of the containment. The Crystal River Unit 3 containment is a steel lined, post tensioned concrete structure nominally 42 inches thick. Post tensioning is achieved utilizing an outer array of horizontal tendons immediately adjacent to an inner array of vertical tendons. The separation is generally in the plane of the horizontal tendons. Inside the separation is 30 inches of concrete and the steel liner plate. This condition has been evaluated relative to current plant conditions and found to represent no degradation in safety. Crystal River Unit 3 personnel in conjunction with industry experts are currently performing a detailed analysis of this separation to determine the cause, extent of condition, the impact on the containment building function and any required repairs prior to plant restart. Operating experience reports are being prepared to share our information with the industry. The station will provide updates as we gain more information concerning this issue. The licensee notified the NRC Resident Inspector. | Steam Generator | |
| ENS 43706 | 10 October 2007 17:12:00 | Information Only Other Unspec Reqmnt 10 CFR 50.72(b)(2)(xi), Notification to Government Agency or News Release | Pressurizer Porv Opened Momentarily with Rcs Discharge of Approximately 10 Gallons | On 10/10/2007 at 1312, Crystal River Unit 3 was performing maintenance on its Pressurizer Pilot Operated Relief Valve (PORV). The I&C technicians were replacing a circuit board card in the circuitry for the PORV. The PORV had been selected to close during the replacement of the card. When the PORV was selected to its auto position, the PORV opened and was immediately closed by the reactor operator. It was estimated that the PORV was opened for 2 second with a total flow of 10 gallons. This rate is in excess of the 25 gpm as found in the EAL. The event was quickly terminated with the closing of the PORV and PORV block valve. The plant remains stable with the PORV and PORV block valve closed. CR3 briefly met the conditions of an Unusual Event, however declaration was not required. The licensee is still trouble-shooting the cause of the event. The reactor is stable at full power and the technical specification action statement requirement for an inoperable PORV valve (TS 3.4.10) have been satisfied. The licensee reported this event for information based on the guidance of NUREG 1022 concerning reporting an event that was rapidly terminated that may have met the criteria of an emergency based on an after the fact review. The licensee notified the State and local authorities and the NRC Resident Inspector. |