Event Notification Report for July 03, 2018

MANUAL REACTOR TRIP DUE TO HIGH STEAM GENERATOR WATER LEVEL

"At 0954 [EDT] on July 3, 2018, with Unit 1 in Mode 1 at 100 percent power, the reactor was manually tripped due to high steam generator water level. The trip was not complex, with all systems responding normally. Operations stabilized the plant in Mode 3. Decay heat is being removed through the main steam lines through the steam dumps and into the condenser.

"The expected actuation of the Auxiliary Feedwater System (an engineered safety feature) is being reported as an eight hour report under 10 CFR 50.72 (b)(3)(iv)(A).

"Unit 2 was not affected.

"There was no impact to the health and safety of the public or plant personnel.

"The NRC Resident Inspectors have been notified."

All control rods inserted and Unit 1 is in an electrical shutdown lineup. The cause of the high steam generator water level transient is being investigated.

TURBINE TRIP SOLENOID FAILED TO ACTUATE DURING TESTING

"At 1753 on 7/3/2018 it was discovered that both sets of turbine trip solenoids were previously unable to actuate within allowable time frames; therefore, this condition is being reported as an eight-hour, non-emergency notification per 10 CFR 50.72(b)(3)(v). At the time of discovery, one set of turbine trip solenoids had been restored.

"There was no impact on the health and safety of the public or plant personnel. The NRC Resident Inspector has been notified."

AGREEMENT STATE REPORT - SOURCE DISCONNECT

The following information was received from the State of Texas by email:

"On July 4, 2018, the Agency [Texas Department of State Health Services] was notified by the licensee's radiation safety officer (RSO) that one of their crews has experienced a source disconnect. The crew was using a QSA 880D exposure device containing a 70 Curie Iridium - 192 source. The licensee did not have a lot of details on the event, but stated the source had been recovered and that no over exposures had occurred. The licensee stated the connector ball on the drive cable was tested after the event and failed the test. The RSO stated they would provide additional information on July 5, 2018. Additional information will be provided as it is received in accordance with SA-300."

Texas Incident- I-9591

TEXAS AGREEMENT STATE REPORT - POTENTIAL OVEREXPOSURE EVENT

The following information was obtained from the state of Texas via email:

"On July 5, 2018, the Agency [Texas Department of State Health Services] was notified by the licensee's [Stanley out of Tulsa, OK] consultant that an overexposure event may have occurred involving radiographers working in the state of Texas, under reciprocity, at a field site near Midland, Texas, but offered no actionable information. At 1620 hours [CDT], the consultant called back and stated that a crew was performing radiography in a pit using a 99.6 Curie iridium - 192 source. The individual who received the high exposure had been working in the dark room. He completed the task he was working on and exited the dark room and went straight to the pit. He picked up the collimator and started to move it while the source was still in the collimator. The other radiographers yelled at him and he dropped the source and left the pit.

"The consultant stated the calculations for the dose to the individual's hand provided by the licensee is 284 rem. The consultant stated the radiographer held the source for about 3 seconds and the dose calculation was based on no shielding. The consultant stated there is currently no apparent injury to the individual's hand. The consultant stated the licensee is contacting REAC/TS in Oak Ridge, Tennessee, for assistance. The licensee's radiation safety officer is conducting an investigation into the event. Additional information will be provided as it is received in accordance with SA-300."

Texas Incident #9592

* * * UPDATE FROM THE STATE OF OKLAHOMA TO HOWIE CROUCH ON 7/6/18 AT 1032 EDT * * *

The following information is excerpted from an email that was received from the state of Oklahoma:

Oklahoma DEQ [Department of Environmental Quality] Radiation Management was contacted by the radiation safety officer (RSO) of Stanley Inspection, License No.: OK-32187-01, after hours on 7/5/2018. Stanley Inspection, a radiography company, was working in Midland, TX under reciprocity, and one of the radiographers potentially overexposed his hand. Stanley Inspection was instructed by Texas to do medical monitoring for the radiographer, including bloodwork and photographs of his overexposed extremity.

Notified R4DO (Miller) and NMSS Events Notifications (email).

* * * UPDATE FROM IRENE CASARES TO DONG PARK ON 7/19/18 AT 1158 EDT * * *

The following information was obtained from the state of Texas via email:

"Stanley Inspection Services reported that a radiation overexposure may have occurred involving radiographers working in Texas, under reciprocity, at a field site on 7/3/2018 near Midland, Texas. Reported to NRC as update on July 19, 2018. After complete investigation and reenactment of the incident the following information was obtained and being provided as an update of the incident.

"On July 3, 2018, a radiographer working a temporary field site project under reciprocity (OK licensee in TX) with another crew had an incident. The radiographer was working in the dark room and was developing film. He completed this task and exited the darkroom. This was the last shot of the day in which this crew was working. It was the last image for this shot in which four images are taken for this weld of a 36 inch pipe at a time of 6.5 minutes each image. They were about to end the workday. It was at dusk and his assistant went to the front of the vehicle to get a flashlight while a member of the other crew showed up. The time of day was between 9 and 10 pm. When this person showed up, the radiographer was exiting the darkroom. These two radiographers both walked down into the pit to retrieve the film, when they were walking to the film, the assistant arrived at the back of the truck, stating that the source was still out and at that time the survey meter being carried by the other crew member (RDS-30, Mirion technologies) was alarming. The person carrying the survey meter was about 2-3 feet behind the first radiographer. The first radiographer had already put his fingers (index and middle) and thumb on the collimator for estimated 3 seconds as he was checking to ensure it had not moved from the mark/film while imaging. He explained that he heard the alarms from the survey and dosimetry meters and they both ran out of the pit. It was reenacted on 16 July to confirm how he placed his fingers on the collimator and estimated the time. The Delta 880, sn D15456, camera was loaded with, QSA, A424-9, 66225G, Ir-192, at an activity of 101.5 curies. The calculated dose to the hand for 3 seconds with a collimator made of tungsten rated at 4 HVL was 25.54 rem for the extremity dose. The initial whole body dose was estimated to be unshielded at 109 mrem. The radiographer had been wearing an electronic dosimeter (Tracerco) which was acting as an alarming rate meter and dosimeter. The film badge was processed with results of 18 mrem. And the dosimetry was reported to have read 24 mrem by the radiographer for that day's work. The dosimeter was sent for verification/accuracy checks. The radiographer had his blood drawn as instructed by REAC/TS and the RSO photographed his fingers/hands for 3 weeks. The radiographer stated he had no abnormal redness, tingling or sensations in the tissue of the hand. The supporting documents and reenactment support an estimated dose of 25.54 rem to the extremity and approximately 20 mrem to the whole body.

"The company is completing its documentation of the incident and will be providing its detailed report with corrective actions, another update will be forthcoming."

Notified R4DO (Young), INES (Milligan) and NMSS Events Notifications via email.

DISCOVERY OF AN UNANALYZED CONDITION THAT SIGNIFICANTLY DEGRADES PLANT SAFETY

"On July 3, 2018, while performing a review of Emergency Operating Procedures, a concern was identified regarding the potential for excessive loss of ultimate heat sink inventory (UHS) through the auxiliary feedwater (AFW) system mini-flow recirculation pathway. This condition would have the potential to prevent the ultimate heat sink from providing an adequate inventory of water for a 30-day mission time.

"The normal water supply for the Callaway AFW system is the condensate storage tank (CST). The CST is a non-safety grade component. The safety-grade supply for AFW is the essential service water (ESW) system. The ESW system is supplied by the UHS. The UHS thermal performance analysis accounts for a loss of UHS inventory to the AFW system up until the point of the accident sequence that the AFW pumps would be secured. The analysis did not include an allowance for loss of UHS inventory through the AFW mini-flow recirculation pathway following the AFW pumps being secured. The EOP guidance that secures the AFW pumps does not isolate the mini-flow recirculation pathway.

"Initial estimates indicate that loss of UHS inventory through the mini-flow recirculation pathway, if not isolated, would preclude the UHS from completing its 30-day mission time. This potential for depletion of the UHS placed the plant in an unanalyzed condition that significantly degraded safety.

"Callaway has issued interim guidance to the on-shift personnel regarding this concern to ensure that the ultimate heat sink water level is maintained at a level that will be adequate to mitigate the potential loss of inventory.

"This condition is reportable per 10 CFR 50.72(b)(3)(ii)(B) for an unanalyzed condition that significantly degrades safety.

"The NRC Resident Inspectors have been notified of this condition."

* * * RETRACTION ON 07/31/2018 AT 1430 EDT FROM LEE YOUNG TO ANDREW WAUGH * * *

"Event Notification (EN) 53485, made on July 3, 2018, is being retracted because re-evaluation performed subsequent to the notification has demonstrated, based on actual plant equipment and environmental conditions, that the unanalyzed inventory losses previously reported by EN 53485 would not have depleted the UHS inventory to an unacceptable level during its 30-day mission time.

"The re-evaluation has led to the conclusion that the previously unanalyzed losses of UHS inventory would not have prevented the UHS from performing its specified safety functions and meeting its 30-day mission time requirements. With the UHS capable of performing its specified safety functions and meeting its 30-day mission time requirements, the systems supported by the UHS would have remained capable of performing their specified safety functions. Based on these considerations, it has been determined that the condition reported in EN 53485 did not result in the plant being in an unanalyzed condition that significantly degraded safety. Consequently, the condition did not meet the criteria for an 8-hour notification per 10 CFR 50.72(b)(3)(ii)(B) for an unanalyzed condition that significantly degrades safety.

"The NRC Resident Inspector has been notified of the Event Notification retraction."

Notified R4DO (Gaddy).