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| Entered date | Event description | |
|---|---|---|
| ENS 55597 | 21 November 2021 14:28:00 | At 1046 EST on November 21, 2021, with Calvert Cliffs Nuclear Power Plant Unit 2 in Mode 1 at 100 percent power, the reactor was manually tripped due to lowering levels in both steam generators following a loss of the 21 and 22 steam generator feed pumps. An Auxiliary Feedwater System actuation occurred to restore steam generator water levels. The trip was not complicated, with all systems responding normally. Decay heat is being removed by the Auxiliary Feedwater System. Calvert Cliffs Nuclear Power Plant Unit 1 is unaffected and remains in Mode 1 at 100 percent power. Due to the Reactor Protection System (RPS) actuation while critical, this event is being reported as a four-hour, non-emergency notification. RPS actuation, per 10 CFR 50.72(b)(2)(iv)(B). Additionally, the automatic actuation of the Auxiliary Feedwater System is being reported as an eight-hour, non-emergency notification, Specific System Actuation, per 10 CFR 50.72(b)(3)(vi)(A). There was no impact on the health and safety of the public or plant personnel. The NRC Resident Inspector has been notified. |
| ENS 55209 | 23 April 2021 08:38:00 | The following was received via email from the State of Georgia. (The licensee) called and reported a gauge stolen off the back of one of their work trucks on April 22, 2021. The technician responsible for the gauge was working on the Augusta Airport project. The gauge was left locked and chained in the back of his truck in the motel parking lot overnight. The technician last saw the gauge at 1900 EDT on April 21, 2021. When (the technician) went to the truck (on April 22, 2021) the chain and lock had been cut and the gauge removed. The local Sheriff has been informed and the case number is 21-112409. This has been assigned and more information is forthcoming. Troxler Model Number: 3400 Serial Number: 22667 Activity: Cs-137 (10mCi); Am-241/Be (40 mCi) Georgia Radioactive Materials Program NMED Report Incident # 40 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. For additional information go to http://www-pub.iaea.org/MTCD/publications/PDF/Pub1227_web.pdf |
| ENS 54819 | 6 August 2020 10:33:00 | The following is a summary of information received via email: On 3/27/20, the Vermont Department of Health (VDH) was notified that a waste transport truck was rejected at a waste facility in Concord, NH. The truck was rejected because radioactive material was detected in the waste. The truck was redirected to Goodenough Rubbish Removal in Brattleboro, VT, and instructed to isolate the waste. On 3/30/20, VDH Radiation Control responded to the waste center. The radioactive waste was identified as clay cat litter containing I-131 with a maximum dose rate of 8.04 mrem/hr on contact and 0.54 mrem/hr at one meter while background measurements were 10 microR/hr. The waste hauler was instructed to isolate the container in a remote section of the recycling center with the contents covered for 80 days. On 4/3/20, VDH issued Vermont Information Notice IN 20-001 (Release of humans and animals receiving I-131 therapy) to all Vermont radioactive materials licensees who are authorized to use I-131. This Information Notice recommends all affected licensees review their I-131 administration procedures, patient release criteria, and pet owner release instructions. On 6/26/20, a VDH inspector returned to survey the material, and found that the radiation levels of the material were indistinguishable from background. With the decay of the I-131 waste this incident has been closed out by VDH on 8/5/20. Vermont Incident No.: VT-20-002 |
| ENS 54485 | 21 January 2020 16:12:00 | The following was received via email: Nature of the defect or failure to comply and the safety hazard which is created or could be created by such defect or failure to comply. Condition 1 (Modified Fixed Core) The purpose of the fixed core is to provide the proper amount of magnetic pull force between itself and the plunger when the solenoid coil is energized. The fixed core is installed within the bonnet assembly and "fixed" in place by a "dimpling" process which captures a machined groove on the fixed core. During Assembly & Testing of a TR Solenoid Operated Valve, a fixed core unexpectedly came out of the bonnet assembly. Further inspections of the fixed core revealed unauthorized modification to the part beyond its design basis to force installation into the bonnet assembly. In the event a modified fixed core was to dislodge from its location within the bonnet, the specific valve assembly would fail to operate to the open position when the solenoid is energized and would remain in its fail safe closed position. Condition 2 (Main Disc Lift Misadjustment): The objective of the disc lift adjustment is to ensure the main disc is in contact with the bonnet base, which provides an "up stop" position while maintaining a minimum clearance between the plunger and the fixed core. Excessive clearance between the plunger and the fixed core reduces the available magnetic force. Conversely, improper adjustment, allowing contact between the plunger and the fixed core, may cause impact damage to the assembly during full pressure/temperature actuation and reduces the maximum flow (Cv) through the valve assembly. It was noted that a disc lift adjustment was not adjusted properly and would reduce the maximum flow. The date on which the information of such defect or failure to comply was obtained. Condition 1 (Modified Fixed Core): During the investigation of the suspect technician, TR identified conditions, which required independent inquiry and subsequently confirmed intentional modification of the fixed core. On December 5, 2019, TR Engineering confirmed the condition. Condition 2 (Main Disc Lift Misadjustment): On November 22, 2019, TR Engineering performed a worst case Cv calculation to determine the amount of restricted flow that would result in the event a 1" y-body valve assembly was short stroked. This would reduce the flow of a 1" y-body valve assembly from a rated Cv of 15 to approximately a Cv of 14. The corrective action which has been, is being, or will be taken; the name of the individual or organization responsible for the action; and the length of time that has been or will be taken to complete the action. Condition 1 (Modified Fixed Core): The discrepant bonnet assembly/fixed core was documented on a NCR (Non Conformance Report) and scrapped. A new bonnet assembly was issued to the valve kit. The valve assembly was reassembled, retested and successfully passed all required production testing. This was an unauthorized modification performed by a single individual (suspect technician). Four additional A& T technicians involved in the bonnet dimpling process were interviewed. All four technicians stated they have never intentionally modified components nor have they ever seen anyone intentionally modifying components in any form. TR investigation considers this to be isolated to the suspect technician. The suspect technician no longer works for the company. Condition 2 (Main Disc Lift Misadjustment): The initial valve assembly was readjusted in accordance with the applicable technical manual and solenoid valve adjustment procedure. The valve assembly was re-tested per the applicable production test procedure and successfully passed all required testing. Upon further investigation of valves assembled by the suspect technician, an additional 3 of 10 valve assemblies were verified to have misadjusted main disc lift. The misadjusted valves were readjusted, tested and successfully passed all production testing prior to shipment. All technicians working on solenoid valve assemblies were given an individual technician qualification exam to determine their understanding of this adjustment in accordance with the existing work instructions. Each technician was tested individually, with Engineering present as a witness. All technicians demonstrated a clear understanding and followed the necessary instructions/procedures to properly adjust the disc lift. TR determined the suspect technician did not follow the official work instructions for the disc lift adjustment in an effort to save time during this process. TR investigation concludes this defect is isolated to the suspect technician. The suspect technician no longer works for the company. This was the same technician involved in Condition 1. Any advice related to the defect or failure to comply about the facility, activity, or basic component that has been, is being, or will be given to purchasers or licensees. Condition 1 (Modified Fixed Core): TR performs production testing on all valve assemblies prior to shipment. TR considers this testing adequate screening to identify this condition at the factory. Satisfactory testing provides reasonable assurance the stated condition does not exist in shipped product. However, TR recommends un-installed bonnet assemblies and complete valve assemblies be returned to TR for re-inspection. This condition potentially affects valve models and bonnet assemblies detailed in Attachment 1 manufactured between 1/1/2018 and 10/31/2019. Any installed valves containing these parts should be reviewed and evaluated for history of operational testing anomalies. Many of these installed valves are subject to regular plant testing, such as 1 OCFR50 Appendix J. Satisfactory performance in this testing will provide reasonable assurance of an acceptable valve condition. Condition 2 (Main Disc Lift Misadjustment): All un-installed Valve Assemblies should be checked to determine if a misadjustment of the main disc lift exists. Although the process to check for a misadjusted valve is not difficult, it requires partial valve disassembly. The instructions for proper adjustment are located in the valve specific Technical Manual. Any 1" Y-body solenoid valve assemblies that have been installed should be reviewed and evaluated by each end user regarding the acceptability of having a lower flow (Cv) rating of 14 in lieu of 15 for the specific system in which they are installed. Any opportunity to disassemble the valve assembly for inspection and readjustment is recommended. This condition potentially affects valve models detailed in Attachment 1 manufactured between 7/1/2015 and 10/31/2019. Should you have any questions regarding this matter, please contact Michael Cinque, General Manager at (631) 293-3800 Very Truly Yours, Michael Cinque General Manager Target Rock, Business Unit of Curtiss-Wright Flow Control Corporation Affected sites are Arkansas Nuclear One, Beaver Valley, Brunswick, Calvert Cliffs, Farley, Fitzpatrick, Hope Creek, Millstone, Nine Mile Point, Oconee, Palo Verde, Sequoyah, Shearon Harris, St. Lucie, South Texas Project, Vogtle, Watts Bar |
| ENS 54466 | 8 January 2020 02:49:00 | On January 7, 2020, Columbia Generating Station (CGS) experienced an equipment failure that resulted in a loss of the seismic assessment instrumentation. This is being reported as a major loss of emergency assessment capability in accordance with regulation 10 CFR 50.72(b)(3)(xiii). No other plant systems were affected. Compensatory measures have been implemented and will remain in place until the seismic system has been restored. The NRC resident has been notified. Licensee received a design basis earthquake alarm, but no other local indication of seismic activity, nor on the U.S. Geological Survey website. Licensee compensatory measures include local readings on seismic instrumentation. |
| ENS 54103 | 6 June 2019 12:02:00 | This 60-day telephone notification is being made in accordance with the reporting requirements specified by 10 CFR 50.73(a)(1) and 10 CFR 50.73(a)(2)(iv)(A) to describe an invalid actuation of a general containment isolation signal affecting multiple Main Steam Isolation Valves (MSIVs). On April 18, 2019 at approximately 0110 EDT, during performance of an ASME reactor vessel leak check, all four inboard MSIVs closed as a result of actuation of the Main Steam Line (MSL) high flow instrumentation. The high flow signal was spurious on the 'D' channel with no flow in the MSLs. Since an actual high flow condition did not exist at the time of the actuation, the actuation was considered invalid. The MSIVs functioned as designed on actuation of the MSL high flow instrumentation. All outboard MSIVs were closed at the time of the actuation in accordance with the vessel leak check procedure. The NRC Resident Inspector has been notified. |
| ENS 53875 | 13 February 2019 14:35:00 | The following information was received via email from the state of North Dakota: Desert NDT, LLC dba Shawcor reported a 3.256 TBq (88 Ci) Iridium-192 sealed source (Industrial Nuclear Model 32, serial #022E) had disconnected from a drive cable connected to an Industrial Nuclear Model IR-100 radiography exposure device (serial #4321) at a temporary job site in Williston, ND on 2/12/2019. The event occurred at 1645 (MST) while the radiography crew, consisting of a radiographer and assistant radiographer, was performing industrial radiography under extreme cold weather conditions on a pipe section. Upon retracting the source after the third exposure, the crew noticed the radiography device's safety latch did not pop up indicating the source in the safe/locked position. Upon performing a radiation survey while approaching the device, the crew noticed an increased exposure rate indicating a source disconnect. The crew immediately retreated from the device and reset an actual 2 mR/hr public dose boundary and contacted their radiation safety officer who made arrangements for authorized retrieval personnel to dispatch to the site. The crew maintained constant surveillance of the site while awaiting the source retrieval personnel. The source was successfully retrieved at 2020 (MST). At the time of the event, the radiographer had received 50 mR and the assistant radiographer 55 mR on their direct reading dosimeters. The retrieval individual received a total of 357 mR to the direct reading dosimeter located on his arm and 243 mR to the direct reading dosimeter located on his chest. Shawcor will provide a detailed report to the North Dakota Department of Health upon establishing the root cause and corrective actions. NMED Item #ND190001 |
| ENS 53538 | 7 August 2018 14:45:00 | At 0909 (EDT) on August 7, 2018, Southern Nuclear Operating Company (SNC) determined a contractor supervisor confirmed positive for alcohol during a random Fitness-for-Duty (FFD) test. The employee's unescorted access to the plant has been suspended. The NRC Resident Inspector has been notified. |