|Entered date||Site||Region||Reactor type||Event description|
|ENS 50787||25 February 2020 08:52:00||Zion||NRC Region 3||Westinghouse PWR 4-Loop|
On 2/3/2015 at 1901 (CST), equipment important to safety failed to function as designed: 33 NAC MAGNASTOR systems containing Spent Nuclear Fuel, and 1 NAC MAGNASTOR system containing GTCC (Greater than Class C) waste, had air inlet vent partial blockage, totaling 50 percent or greater, due to environmental conditions, i.e., snow. (Please Note, no VCC systems reached full blockage.) NO personnel radiation exposure. Actions Taken lAW the NAC FSAR, Rev. 5, which included actions to immediately return the systems to less than 50 percent blockage and ongoing maintenance activities to return all systems to full operability. Additional information: 1. On 2/4/2015 at 0445 hrs. All 34 failed systems were restored to less than 50 percent blockage. 2. lAW the NAC FSAR we have 30 days from time of discovery to return each system to full operability. 3. A report will be followed up within 60 days per 10 CFR 72.75.g The licensee will notify the NRC Inspector and the State of Illinois.
This phone notification is being made to retract an earlier '24 Hour Report' made on February 4, 2015 at 1815 CST, NRC event #50787. On February 4, 2015 at 1810 CST, Zion Station notified NRC that on February 3, 2015 at 1901 CST, Equipment Important To Safety failed to function as designed that being 33 NAC MAGNASTOR systems containing Spent Nuclear Fuel and 1 NAC MAGNASTOR containing GTCC waste had their Inlet vents partially blocked, totaling 50% or greater, due to environmental conditions, i.e. Snow. This appeared to meet criteria of Non-Emergency notification under 10 CFR 72.75d(1)(i). NAC International has provided documentation stating we have 58 hours to perform the immediate action to unblock the VCC vents to greater than 50% and 30 days to completely unblock all the vents. This documentation is attached to this notification. Upon further review by Exelon Management, Zion Solutions Management and NAC, using criteria established in Sections 18.104.22.168 and 12.2.2 of the SER for CoC 72-1031, Amendment 0, no limits were exceeded. Actions were immediately initiated to restore the 34 failed systems to less than 50% blockage and were completed in less than 10 Hours. This is well within the 58 hour SAR basis. This is the basis for retracting the notification. Based on the above, (the licensee) management concludes this event does not meet the 24-hour reporting criteria established in 10 CFR 72.75d(1)(i). The R3DO(Pelke) was notified.
|ENS 49728||15 January 2014 16:25:00||Zion||NRC Region 3||Westinghouse PWR 4-Loop||A licensed supervisor had a confirmed positive for alcohol during a for-cause fitness-for-duty test. The employee's access to the plant has been terminated.|
|ENS 49304||23 August 2013 11:39:00||Zion||NRC Region 3||Westinghouse PWR 4-Loop||The following significant FFD policy violations and programmatic failures must be reported to the NRC Ops Center within 24 hours by telephone after the licensee or other entity discover the violation. (1) The use, sale, distribution possession or presence of illegal drugs, or the consumption or presence of alcohol within a protected area. Ours (licensee) is a conservative decision to notify due to the fact that the contraband was found in the restricted area and NOT in the protected area. On 8/22/13 at approximately 1300 hours, an employee conducting demolition work on the 542 level of the Auxiliary Building discovered an old dust covered pint glass bottle of Jim Beam Bourbon Whiskey containing approximately 1 inch of brown liquid which, when opened, smelled of alcohol. The bottle was located in bus trays 12 to 15 feet above the floor. The employees retrieved the bottle and handed it to an individual on the ground. Radiation Protection (RP) personnel bagged the bottled due to it being in a contaminated area. The bottle was surveyed by RP and released to Security. The bottle was removed to the FFD Office and the liquid was disposed of in the toilet. The glass bottle was then disposed of offsite. The licensee will notify the NRC Resident Inspector.|
|ENS 43202||28 February 2007 14:16:00||Zion||NRC Region 3||Westinghouse PWR 4-Loop||This is a non-emergency event notification in accordance with 10 CFR 20.2201(a)(1)(ii) to report an accountability discrepancy of licensed material. In the process of reviewing records, it was identified that all disposition records for reactor incore detectors could not be found. The reactor incore detectors contain very small quantities of U-235 and were used to monitor reactor power at Zion Station from 1972 to 1988. The unaccounted for material was classified as missing on February 28, 2007 due to lack of records documenting the current location of the detectors; however, based on available records and discussions with former Zion Nuclear Material Custodians, it is believed that these detectors were shipped as radioactive waste to the Barnwell Low-Level Radioactive Waste Disposal Facility located in South Carolina. A search of storage locations at Zion was performed, but the detectors have not been located. Historical records indicate that it was common practice for Zion Station to dispose of detectors in this manner. There is no evidence of theft or diversion of these detectors. The incomplete records involve 43 incore detectors received onsite prior to 1988. The detectors contain an extremely small amount of Special Nuclear Material and pose no significant safety concern. Depending on design, each incore detector contained between 0.0025 grams to 0.0004 grams of Uranium 235 resulting in an aggregate quantity of approximately 0.102 grams of Uranium 235. The activity of this quantity is approximately 0.22 microcuries. This quantity is greater than the reportability threshold of 10 times the quantity specified in Appendix C to 10 CFR 20 which is 0.01 microcuries. A subsequent written report will be made in accordance with 10 CFR 20.2201(b). The licensee will notify the NRC Resident Inspector and the State. THIS MATERIAL EVENT CONTAINS A "LESS THAN CAT 3" LEVEL OF RADIOACTIVE MATERIAL Sources that are "Less than IAEA Category 3 sources," are either sources that are very unlikely to cause permanent injury to individuals or contain a very small amount of radioactive material that would not cause any permanent injury. Some of these sources, such as moisture density gauges or thickness gauges that are Category 4, the amount of unshielded radioactive material, if not safely managed or securely protected, could possibly - although it is unlikely - temporarily injure someone who handled it or were otherwise in contact with it, or who were close to it for a period of many weeks. This source is not amongst those sources or devices identified by the IAEA Code of Conduct for the Safety & Security of Radioactive Sources to be of concern from a radiological standpoint. Therefore is it being categorized as a less than Category 3 source|