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Event Notification Report for September 16, 2016

U.S. Nuclear Regulatory Commission
Operations Center

Event Reports For
09/15/2016 - 09/16/2016

** EVENT NUMBERS **


52090 52242 52244

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Fuel Cycle Facility Event Number: 52090
Facility: WESTINGHOUSE ELECTRIC CORPORATION
RX Type: URANIUM FUEL FABRICATION
Comments: LEU CONVERSION (UF6 to UO2)
                   COMMERCIAL LWR FUEL
Region: 2
City: COLUMBIA State: SC
County: RICHLAND
License #: SNM-1107
Agreement: Y
Docket: 07001151
NRC Notified By: NANCY PARR
HQ OPS Officer: DONG HWA PARK
Notification Date: 07/14/2016
Notification Time: 18:49 [ET]
Event Date: 07/13/2016
Event Time: [EDT]
Last Update Date: 09/15/2016
Emergency Class: NON EMERGENCY
10 CFR Section:
PART 70 APP A (a)(4) - ALL SAFETY ITEMS UNAVAILABLE
PART 70 APP A (b)(1) - UNANALYZED CONDITION
Person (Organization):
DANIEL RICH (R2DO)
NMSS_EVENTS_NOTIFIC (EMAI)

Event Text

DEGRADED SAFETY ITEMS CAUSED BY URANIUM BUILDUP

"On July 13, 2016, it was determined by the Environment, Health and Safety (EH&S) department that scrubber clean-out material, found in the S-1030 scrubber transition section during the annual maintenance shutdown that occurred in late May, potentially exceeded the uranium mass limit for the scrubber transition.

"(IROFS [Items Relied on for Safety] VENT-S1030-110) requires annual inspection and removal of significant solids buildup in the transition section. Upon inspection, significant buildup was found, and the ductwork was opened to permit extensive cleanout. 36 containers of material with a total gross weight of 210.4 kg was removed from the inlet transition during the cleanout on May 28th to May 29th. Grab samples were subsequently taken from each container and analyzed for uranium concentration. On July 13th, the EH&S department was made aware that the grab sample results averaged 47.8% U. Although the exact uranium mass cannot be determined until the material is dissolved and representatively sampled, available evidence suggests that the mass limit of 29 kg U in the inlet transition was exceeded. The 29 kg U limit is based on an optimally moderated, fully reflected spherical geometry which very conservatively bounds the conditions in the inlet transition of the scrubber. IROFS remained to limit the quantity of uranium available to the scrubber (IROFS VENT-S1030-101, -102, -103 & -104), which are physical barriers designed to minimize uranium in the airflow entering the transition area. Continuous liquid spraying in the inlet transition section to limit solids accumulation (IROFS VENT-S1030-109) was also in place.

"The inlet transition and scrubber were thoroughly cleaned, and the uranium bearing solids were placed into favorable geometry containers. Also, the inspection and cleanout of the transition frequency was increased to monthly.

"Based on available but degraded IROFS, this accident sequence was unlikely. Therefore, this mass accident sequence does not meet the performance requirements of 10CFR70.61. The actual configuration remained safe at all times. Also, no external conditions affected the event.

"Immediate Corrective Actions:
NRC Region II personnel, who were onsite at the CFFF [Columbia Fuel Fabrication Facility], were made aware of the discovery.

"The Conversion area was shutdown to plan for a second extensive scrubber clean-out to validate that the accumulation of solids is a slow buildup over time. The last extensive cleanout was performed in 2009.

"An extent of condition was performed to determine if other scrubbers potentially had significant uranium buildup. Inspection data indicated that this material accumulation issue was limited to the S-1030 scrubber.

"This event has been entered into the facility Corrective Action Prevention And Learning system (CAPAL) #100397353."

* * * UPDATE PROVIDED BY NANCY PARR TO JEFF ROTTON AT 1025 EDT ON 07/26/2016 * * *

"Onsite chemical analysis confirmed that uranium mass limit for the scrubber transition piece was exceeded. The accumulated material contained 87 kgs of Uranium.

"The Criticality Safety Evaluation for this system was revised and implemented on July 20, 2016 to add Items Relied on For Safety to prevent recurrence of a mass exceedance while the causal analysis and additional corrective actions are completed."

Notified R2DO (Nease) and NMSS Events Notification Group via email.

* * * UPDATE PROVIDED BY NANCY PARR TO HOWIE CROUCH AT 1749 EDT ON 07/31/2016 * * *

"On July 31, 2016, it was determined by the Environment, Health and Safety (EH&S) department that clean-out material found in the S-1030 scrubber packing and floor also potentially exceeded the uranium mass limit for the scrubber criticality safety evaluation. Over years of operations, the same available but degraded mass prevention and inspection/clean-out IROFS did not prevent exceedance of the mass limit.

"This report is being upgraded to a 1 Hour Event Notification based on 10CFR70 Appendix A(a)(4).

"There was no consequence to the public, the workers or the environment.

"The scrubber process will remain in a safe shutdown mode until further investigation and corrective actions are completed."

Notified R2DO (Rose), IRD (Grant), NMSS EO (Kotzalas) and NMSS Events Notification via email.

* * * UPDATE FROM JOHN HOWELL TO VINCE KLCO AT 1620 EDT ON 8/7/2016 * * *

"On August 6, 2016 at 1700, it was reported to the Environment, Health and Safety (EH&S) department that residual material located within the abandoned S-1056 scrubber was sampled and confirmed to contain Uranium.

"24 Hour Event Notification based on 10CFR70 Appendix A(b)(1) 'Any event or condition that results in the facility being in a state that was not analyzed, was improperly analyzed, or is different from that analyzed in the Integrated Safety Analysis, and which results in failure to meet the performance requirements of 10CFR70.61.'

"The S-1056 is an out-of-service scrubber. When operational, it scrubbed the acid fumes from the Conversion area. It currently is an unanalyzed system without IROFS or controls. The reported volume of approximately 15 kg is well within safety margins.

"It was taken out of service in 2002, when the S-1030 scrubber replaced it. The material in the S-1056 was discovered as an extent of condition for the S-1030 event.

"The discovery and sampling were documented in Redbook 71409. At no time was there any actual or potential health and safety consequence to the workers, the public, or the environment."

The licensee notified the NRC Regional Inspector (Lopez).

Notified the R2DO (Suggs), R2RA (Haney) and NMSS Events Notification Group via email.

* * * UPDATE AT 1546 EDT ON 8/23/16 FROM NANCY PARR TO JEFF HERRERA * * *

"On August 23, 2016, during the extent of condition for this S-1030 scrubber system event, a review of inspection video for the S-1030 ductwork in Conversion identified material accumulation in an elbow which potentially could exceed the uranium mass limit for the elbow section (36.5 kgU).

"This report is being updated based on a potential to meet the 10 CFR 70 Appendix A(a)(4) in the ductwork.

"There was no consequence to the public, the workers or the environment.

"The scrubber process will remain in a safe shutdown mode until further investigation and corrective actions are completed."

The Region IV Project Managers were notified.

Notified the R2DO (Michel), IRDMOC (Stapleton) and NMSS Events Notification Group (via email).

* * * UPDATE AT 1810 EDT ON 9/15/16 FROM NANCY PARR TO DANIEL MILLS * * *

"24-Hour Event Notification based on 10 CFR 70 Appendix A(b)(1) 'Any event or condition that results in the facility being in a state that was not analyzed, was improperly analyzed, or is different from that analyzed in the Integrated Safety Analysis, and which results in failure to meet the performance requirements of 10 CFR 70.61.'

"On September 15, 2016 at 1204 EDT, it was reported to the Environment, Health and Safety (EH&S) department that residual material was located within the abandoned 3A/3B ventilation system. Based on gamma radiation surveys, the material contains Uranium.

"The 3A/3B system was taken out of service in 2002, when the S-1030 scrubber replaced it. When operational, it removed chemical fumes and particulate matter from the Conversion area. The material in the system was discovered as an extent of condition for the S-1030 event.

"When taken out of service, the system was isolated from the introduction of any additional material and/or moderator. However, because the system is out of service, it is considered an unanalyzed system without IROFS or controls. The reported depth of material in the duct appears well within analyzed safety margins for similar systems.

"At no time was there any actual or potential health and safety consequence to the workers, the public, or the environment.

"UPDATED INFORMATION FROM AUGUST 23, 2016 NOTIFICATION:
This notification also serves to update previously reported information provided on August 23, 2016 where a review of inspection video for the S-1030 ductwork in Conversion identified material accumulation in an elbow which potentially could exceed the uranium mass limit for the elbow section (36.5 kg U). This report was made based on a potential to meet the 10 CFR 70 Appendix A(a)(4) in the ductwork. The material was removed from the ductwork and weighed. The total weight of the material removed was 5.5 kgs in the elbow and 3.0 kgs in a horizontal section of the duct, which is well below the mass limit in the safety basis. Therefore, the information from the August 23, 2016 potential report is retracted."

Notified the R2DO (Walker) and NMSS Events Notification Group (via email).

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Power Reactor Event Number: 52242
Facility: ARKANSAS NUCLEAR
Region: 4 State: AR
Unit: [1] [ ] [ ]
RX Type: [1] B&W-L-LP,[2] CE
NRC Notified By: DON WALLS
HQ OPS Officer: DONALD NORWOOD
Notification Date: 09/15/2016
Notification Time: 11:18 [ET]
Event Date: 09/15/2016
Event Time: 09:08 [CDT]
Last Update Date: 09/15/2016
Emergency Class: NON EMERGENCY
10 CFR Section:
50.72(b)(3)(ii)(B) - UNANALYZED CONDITION
50.72(b)(3)(v)(A) - POT UNABLE TO SAFE SD
50.72(b)(3)(v)(B) - POT RHR INOP
50.72(b)(3)(v)(D) - ACCIDENT MITIGATION
Person (Organization):
RAY AZUA (R4DO)

Unit SCRAM Code RX CRIT Initial PWR Initial RX Mode Current PWR Current RX Mode
1 N Y 90 Power Operation 90 Power Operation

Event Text

POTENTIAL UNANALYZED CONDITION BASED ON IDENTIFIED NON-CONFORMING CONDITIONS

"During performance of an extent of condition evaluation of protection for Technical Specification (TS) equipment from the damaging effects of tornadoes, Arkansas Nuclear One, Unit 1, identified non-conforming conditions in the plant design such that specific TS equipment on Unit 1 is considered not [to] be adequately protected from tornado missiles. The reportable condition is postulated by tornado missiles entering vital switchgear rooms 99 and 100 and striking vital switchgears in the rooms. A tornado could generate multiple missiles capable of striking the Unit 1 vital switchgear and rendering both safety related AC electrical trains inoperable.

"This condition is reportable per 10 CFR 50.72(b)(3)(ii)(B) for any event or condition that results in the nuclear power plant being in an unanalyzed condition that significantly degrades plant safety, and per 10 CFR 50.72(b)(3)(v) for any event or condition that at the time of discovery could have prevented the fulfillment of the safety function of structures or systems that are needed to (A) safe shutdown capability, (B) residual heat removal capability, or (D) accident mitigation.

"This condition was identified as part of an on-going extent of condition review of potential tornado missile related site impacts. Licensee Event Report (LER) 50-313/2016-002-00 was recently submitted addressing previously identified tornado missile vulnerabilities at the Unit 1 plant.

"Enforcement discretion per Enforcement Guidance Memorandum EGM 15-002 has been implemented and required actions taken. Corrective actions will be documented in a follow-on licensee event report.

"The licensee has notified the NRC Resident Inspector."

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Power Reactor Event Number: 52244
Facility: COMANCHE PEAK
Region: 4 State: TX
Unit: [1] [2] [ ]
RX Type: [1] W-4-LP,[2] W-4-LP
NRC Notified By: TIMOTHY BENNETT
HQ OPS Officer: JOHN SHOEMAKER
Notification Date: 09/16/2016
Notification Time: 00:14 [ET]
Event Date: 09/15/2016
Event Time: 15:40 [CDT]
Last Update Date: 09/16/2016
Emergency Class: NON EMERGENCY
10 CFR Section:
50.72(b)(3)(ii)(B) - UNANALYZED CONDITION
50.72(b)(3)(v)(C) - POT UNCNTRL RAD REL
50.72(b)(3)(v)(D) - ACCIDENT MITIGATION
Person (Organization):
RAY AZUA (R4DO)

Unit SCRAM Code RX CRIT Initial PWR Initial RX Mode Current PWR Current RX Mode
1 N Y 100 Power Operation 100 Power Operation
2 N Y 100 Power Operation 100 Power Operation

Event Text

POTENTIAL DEGRADATION OF ECCS PUMP PRESSURE INDICATORS

"During a review of commercial grade dedication records for a Unit 1 [Emergency Core Cooling System ECCS] Centrifugal Charging Pump discharge pressure gauge, it was identified that the process side of the diaphragm seal utilizes a Teflon (PTFE) gasket. Further review found Teflon (PTFE) to be installed in the pressure gauge seal assembly for all four of the Centrifugal Charging Pumps and both of the Positive Displacement Charging Pumps on Units 1 and 2.

"Teflon (PTFE) is a restricted material normally prohibited from use in contact with reactor coolant or in radiation environments. Teflon (PTFE) is not radiation tolerant and significantly degrades in a radiation environment. The Teflon (PTFE) used in these pressure gauges could fail during a LOCA [Loss of Coolant Accident] which could cause the [ECCS] Centrifugal Charging Pumps and both of the Positive Displacement Charging Pumps on Units 1 and 2 to be inoperable, and exceed system leakage limits. Excessive leakage from systems which would contain post-LOCA recirculation fluid would challenge onsite and offsite dose estimates and in-plant post-accident accessibility. This represents an unanalyzed condition.

"Currently, the pressure gauges for all four of the [ECCS] Centrifugal Charging Pumps and both of the Positive Displacement Charging Pumps on Units 1 and 2 have been isolated until this issue can be further evaluated. Luminant Power believes that the Teflon (PTFE) has existed in the pressure gauges since initial plant licensing. Luminant Power is currently investigating the extent of the condition and repair techniques.

"The NRC Resident Inspector has been notified."

Page Last Reviewed/Updated Friday, September 16, 2016
Friday, September 16, 2016