| U.S. Nuclear Regulatory Commission
Operations Center Event Reports For
07/01/2009 - 07/02/2009 ** EVENT NUMBERS ** |
 | General Information or Other | Event Number: 44986 | Rep Org: WA DIVISION OF RADIATION PROTECTION
Licensee: PERMA-FIX NORTHWEST
Region: 4
City: RICHLAND State: WA
County:
License #: WN-I0508-1
Agreement: Y
Docket:
NRC Notified By: SEAN MURPHY
HQ OPS Officer: MARK ABRAMOVITZ | Notification Date: 04/13/2009
Notification Time: 12:21 [ET]
Event Date: 02/03/2009
Event Time: [PDT]
Last Update Date: 07/01/2009 | Emergency Class: NON EMERGENCY
10 CFR Section:
AGREEMENT STATE
| Person (Organization):
JACK WHITTEN (R4)
ANGELA McINTOSH (FSME)
CYNDI JONES (NSIR)
| Event Text AGREEMENT STATE REPORT - POTENTIAL OVEREXPOSURE TO THE LUNGS
The following report was received from the state of Washington via e-mail:
"On February 9 2009, a worker was sent for a lung count at the Battelle (Pacific Northwest National Laboratory) lung counter for a bioassay measurement. The lung count was ordered due to the worker working in an area where airborne contamination levels could cause more then 2.5 DAC-hrs (with respiratory protection factors applied), and greater then 520 DAC-hrs assuming no respiratory protection was worn in one day. The reason for requiring this count was to ensure that measures used to protect the workers were functioning properly. The workers first lung count detected approximately 0.2 nCi of Am-241. Assuming the exposure was from 10 days prior, the intake was approximately 1.9 nCi Am-241. The annual limit of intake for Am-241 is 6 nCi (1micron AMAD particle size). The estimated dose was about 1/3 of the annual limit, or 16 REM CDE (Annual limit 50 REM). The worker had previous whole body exposure, but this added amount did not cause a limit to be exceeded.
"On March 25, 2009 the licensee informed the Washington State Department of Health [DOH] that further testing by Battelle caused a revision to the original calculated dose and the new calculated dose would exceed the 50 REM CDE limit. The date of exposure (February 3, 2009) was assumed by the licensee, based on air sample data and the use of respiratory protection that may not have provided adequate coverage (use of filtering respirator instead of supplied air). On February 3, the worker was in a containment in which air sample results were about 1e-8 microCi/ml gross alpha activity concentration for several hours and was wearing a Powered Air Purifying Respirator (PAPR, protection factor of 1000). Bioassay results (fecal) from one other worker who was also in the containment showed a small amount of activity, and a dose was assigned to this second worker that did not exceed the legal limit. The second workers lung count was less than detection limits.
"The cause is still unknown.
"Contributing factors: High airborne activity, loss of respiratory protection.
"DOH is conducting an investigation of this incident.
"Corrective action : Curtailment of work in containment, training on removal of anti contamination clothing and respirator, investigation of respiratory protection failure.
"There was no media coverage of this incident.
"Activity and isotope(s) involved: Am-241, Pu-240/241
Overexposures: (number of workers/members of public; dose estimate; body part receiving dose; consequence): There was one potential overexposed worker, no members of the public were exposed, estimated dose to the worker is about 100 REM CDE and 5 REM CEDE. This value will change following further measurements, investigation and calculations.
"Worker was removed from the restricted area, work in the area where the intake was assumed to occur was stopped, pending the outcome of further investigation."
Washington State Incident Number: WA-09-013
* * * UPDATE PROVIDED VIA EMAIL FROM KETTER TO PARK AT 0823 EDT ON 7/1/09 * * *
"On June 22, 2009 the licensee informed the Washington State Department of Health that the Committed Effective Dose Equivalent (CEDE) for the worker was 6.8 cSv (6.8 REM) and the Committed Dose Equivalent (CDE) was 120 cSv (120 REM) to the bone surface. The workers Deep Dose Equivalent (DDE) from his dosimetry for the first quarter 2009 was 0.3mSv (30 mRem). The dose calculation was completed by a consultant for the licensee. Intake was calculated using methodology of ICRP 30, modified for clearance function. Intake for Am-241 was calculated from lung deposition and calculated clearance rates. Intake of Plutonium (Pu) was inferred from excreta bioassay results and assumed ratios of Am-241 to Pu. Dose was calculated using CINDY code version 1.2. The particle size was considered, and a 1micron Activity Median Aerodynamic Diameter (AMAD) was chosen as the best fit. The total calculated intakes are: Am-241 153 Bq (4.14 nCi), Pu239/240 89.9 Bq (2.43 nCi),Pu 238 16.8 Bq (0.455 nCi).
"The exact cause of the incident is unknown. The assumed cause is a failure of the respiratory protection system. The licensees corrective actions to prevent reoccurrence are to test each worker with a challenge gas prior to high risk work, increased engineering controls to mitigate airborne contaminants, specific training using phosphorescent powder and black lights for workers, more frequent bioassay samples, inclusion of nasal smears for immediate detection of intakes, use of supplied air respirators over air filtering respirators for high risk work, and training for workers, managers and health physics staff. Note that work was resumed in the area, and no further exposures have occurred.
"Worker was removed from the restricted area, work in the area where the intake was assumed to occur was stopped, changes to operations and training methods, changes to engineering controls, changes to testing of respirators prior to use.
"Contributing factors [are] high airborne activity, [and] loss of respiratory protection.
"DOH has completed an investigation of this incident.
"There was no media coverage of this incident.
"There was one overexposed worker. No members of the public were exposed. Estimated dose to the worker was 120 REM CDE and 6.8 REM CEDE."
Notified the R4DO (Pick) and FSME EO (McIntosh). |
| General Information or Other | Event Number: 45007 | Rep Org: WA DIVISION OF RADIATION PROTECTION
Licensee: CANCER CARE NORTHWEST PET CENTER
Region: 4
City: SPOKANE State: WA
County:
License #: M0227
Agreement: Y
Docket:
NRC Notified By: BRANDON KETTER
HQ OPS Officer: HOWIE CROUCH | Notification Date: 04/21/2009
Notification Time: 14:39 [ET]
Event Date: 04/14/2009
Event Time: [PDT]
Last Update Date: 07/01/2009 | Emergency Class: NON EMERGENCY
10 CFR Section:
AGREEMENT STATE
| Person (Organization):
VINCENT GADDY (R4DO)
ANGELA MCINTOSH (FSME)
| Event Text AGREEMENT STATE REPORT - POTENTIAL MEDICAL MISADMINISTRATION
The following information was obtained from the State of Washington via email:
"On 15 April 2009, the licensee notified Washington Office of Radiation Protection by phone of a possible HDR (high dose-rate Remote after-loader Brachytherapy device) malfunction during a patient prostate treatment on 14 April 2009. The licensee discovered the event immediately upon termination of the treatment.
"The aluminum connector to needle 13 detached from the plastic guide tube. It is possible that the source wire or the dummy wire, during retraction, snagged on the seam between the aluminum connector and the plastic guide tube. The HDR is connected to the plastic guide tube, the plastic guide tube is attached (glued) to the aluminum connector, and the aluminum connector screws into the needles that are implanted in the patient.
"It is unknown whether the source wire successfully entered needle 13 as planned; or the source wire failed to enter needle 13 and therefore hung about 6 inches past the disconnected guide tube in open air, for the 32 second dwell time assigned to that particular needle. The event occurred with needle 13 of the 17 treatment needles. The source wire did retract normally after the event. The event did not interfere with the remaining treatment needles.
Isotope and Activity involved: Iridium-192, 185.2 GBq (5.0 curies). Source serial number: 02-01-0080-001-0121.
Overexposures: The dose possibly differed by approximately 180 rads to a small volume of the prostate in vicinity of needle 13. If so, then the total dose would be less than 5% under-dose for the total treatment. The dwell time for needle 13 could have resulted in as much as 12.5 Gy (1250 Rem) to a small area of skin on the inner thigh. Several subsequent inspections of the patient have found no skin reaction. After discussion with the attending physician and examination of the patient's skin, the licensee does not believe there was any clinically significant effect to the patient.
Washington Incident Number: WA-09-015
* * * UPDATE PROVIDED VIA EMAIL FROM KETTER TO PARK AT 0823 EDT ON 7/1/09 * * *
"Updated, corrected event narrative: On 15 April 2009, the licensee notified Washington Office of Radiation Protection by phone of a possible HDR (high dose-rate Remote after-loader Brachytherapy device) malfunction during a patient prostate treatment on 14 April 2009. The licensee discovered the event immediately upon termination of the treatment.
"The aluminum connector to needle 13 detached from the extension adaptor. The HDR is connected to the plastic guide tube, the plastic guide tube is attached to the extension adaptor (which includes the attached (glued) aluminum connector, and the aluminum connector screws into the needles that are implanted in the patient.
"The root causes of the failure of the adhesive that attached the aluminum connector to the plastic extension adaptor are: sterilization of the extension adaptor (manufacturer's written product information cautions that sterilization may cause adhesive failure), and reuse of extension adaptors (manufacturer's written product information recommends for single use only).
"It is unknown whether the source wire successfully entered needle 13 as planned; or the source wire failed to enter needle 13 and therefore hung about 6 inches past the disconnected guide tube in open air, for the 32 second dwell time assigned to that particular needle. The event occurred with needle 13 of the 17 treatment needles. The source wire did retract normally after the event. The event did not interfere with the remaining treatment needles.
"The dose possibly differed by approximately 180 rads to a small volume of the prostate in vicinity of needle 13. If so, then the total dose would be less than 5% under-dose for the total treatment. The dwell time for needle 13 could have resulted in as much as 12.5 Gy (1250 Rem) to a small area of skin on the inner thigh. Several subsequent inspections of the patient have found no skin reaction. After discussion with the attending physician and examination of the patient's skin, the licensee does not believe there was any clinically significant effect to the patient."
Notified the R4DO (Pick) and FSME EO (Burgess).
A Medical Event may indicate potential problems in a medical facility's use of radioactive materials. It does not necessarily result in harm to the patient. |
| !!!!! THIS EVENT HAS BEEN RETRACTED. THIS EVENT HAS BEEN RETRACTED !!!!! | | Fuel Cycle Facility | Event Number: 45163 | Facility: HONEYWELL INTERNATIONAL, INC.
RX Type: URANIUM HEXAFLUORIDE PRODUCTION
Comments: UF6 CONVERSION (DRY PROCESS)
Region: 2
City: METROPOLIS State: IL
County: MASSAC
License #: SUB-526
Agreement: Y
Docket: 04003392
NRC Notified By: MICHAEL GREENO
HQ OPS Officer: PETE SNYDER | Notification Date: 06/25/2009
Notification Time: 13:06 [ET]
Event Date: 06/24/2009
Event Time: 10:45 [CDT]
Last Update Date: 07/01/2009 | Emergency Class: NON EMERGENCY
10 CFR Section:
40.60(b)(1) - UNPLANNED CONTAMINATION
| Person (Organization):
GERALD MCCOY (R2DO)
BRIAN SMITH (NMSS)
| Event Text ACCESS RESTRICTION DUE TO UNPLANNED CONTAMINATION
"An unplanned airborne contamination event occurred beginning June 24, 2009 at 1045 at the Honeywell Metropolis, IL facilities' pond mud calciner area. Access was restricted to the area by requiring respiratory protection to be worn.
"Average airborne concentrations during the following 24 hour period were 7.19 E -11 microcuries per cubic centimeter which exceeds the administrative limit of 5 E -12 microcuries per cubic centimeter. Natural uranium dust was the isotope involved.
"There was no known effect to employees. This event is being entered into the facilities corrective action program."
* * * UPDATE AT 1020 EDT ON 07/01/09 FROM BOB STOKES TO S. SANDIN * * *
The licensee is retracting this report based on the following:
"[The licensee is] withdraw[ing] the event reported June 25th, 2009 Event Number 45163. Following a review of the circumstances associated with the report [the licensee] determined that the event did not meet the criteria as described in 10CFR40.60(b). The event review determined that the contamination event was expected. And the area DID have a respiratory protection requirement in place at the time of the elevated air activity."
The licensee informed NRC Region 2 (John Pelchat). Notified R2DO (Musser) and NMSS (Easton). |
| General Information or Other | Event Number: 45164 | Rep Org: TEXAS DEPARTMENT OF HEALTH
Licensee: FLINT HILLS RESOURCES LP
Region: 4
City: PORT ARTHUR State: TX
County:
License #: 00547
Agreement: Y
Docket:
NRC Notified By: ART TUCKER
HQ OPS Officer: BILL HUFFMAN | Notification Date: 06/26/2009
Notification Time: 11:57 [ET]
Event Date: 09/01/2008
Event Time: [CDT]
Last Update Date: 06/26/2009 | Emergency Class: NON EMERGENCY
10 CFR Section:
AGREEMENT STATE
| Person (Organization):
DALE POWERS (R4DO)
ANGELA MCINTOSH (FSME)
| Event Text AGREEMENT STATE REPORT - GAUGE SHUTTER FAILED TO CLOSE
The following information was received from the State via e-mail:
"On June 25, 2009, at 1630 the Agency was notified by the licensee that while looking for information requested by the State for a previous gauge failure ( EN 44981), the licensee discovered an additional event. This event occurred in early September, 2008, and had not been reported as required. The event involved an Ohmart/VEGA Model SH-F2 level gauge containing a 300 millicurie ( 228 mCi calculated current activity) Cesium (Cs) - 137 source. The gauge shutter would not close due to a sheared shutter rotor. The manufacturer was notified, and a technician arrived at the facility [located in Odessa, TX] on September 30, 2009. The technician replaced the rotor, cleaned and lubricated the gauge, and the gauge operated normally. The technician found that a great deal of material had collected in the source holder causing the failure. The licensee has removed all of their nuclear gauges and is in the process of terminating their license."
Texas Incident Report # I-8642 |
| General Information or Other | Event Number: 45165 | Rep Org: WISCONSIN RADIATION PROTECTION
Licensee: WHEATON FRANCISCAN HEALTHCARE - ST. JOSEPH
Region: 3
City: MILWAUKEE State: WI
County:
License #: 079-1288-01
Agreement: Y
Docket:
NRC Notified By: DIANA SULAS
HQ OPS Officer: JOHN KNOKE | Notification Date: 06/26/2009
Notification Time: 12:11 [ET]
Event Date: 06/25/2009
Event Time: [CDT]
Last Update Date: 06/26/2009 | Emergency Class: NON EMERGENCY
10 CFR Section:
AGREEMENT STATE
| Person (Organization):
ANN MARIE STONE (R3DO)
ANGELA MCINTOSH (FSME)
| Event Text AGREEMENT STATE REPORT INVOLVING MEDICAL EVENT
The following information was provided by the State of Wisconsin via email:
"On June 26, 2009, the Radiation Safety Officer (RSO) notified DHS of a probable medical event that occurred on June 25, 2009 involving an HDR treatment to the esophagus. The authorized user intended to insert the applicator 2 cm past the distal part of the esophageal tumor. A GI specialist verified the location prior to treatment using a scope. Post treatment location of the applicator was reviewed using an AP lateral film. It was then realized that the applicator went 10 cm too far. The prescribed dose was 500 cGy. Therefore, a dose was given to a organ or tissue other than the intended treatment site that exceeds 0.5 Sv (50 rem) to an organ or tissue, and was 50% or more of the dose expected from the administration defined in the written directive (DHS 157.72(1)(a)(3.). DHS inspectors will investigate June 29, 2009."
Wisconsin Incident Number: WI090005
A Medical Event may indicate potential problems in a medical facility's use of radioactive materials. It does not necessarily result in harm to the patient. |
| General Information or Other | Event Number: 45167 | Rep Org: NC DIV OF RADIATION PROTECTION
Licensee: UNC CHARLOTTE
Region: 1
City: CHARLOTTE State: NC
County:
License #: 060-0241-1
Agreement: Y
Docket:
NRC Notified By: SHARN JEFFRIES
HQ OPS Officer: STEVE SANDIN | Notification Date: 06/26/2009
Notification Time: 15:30 [ET]
Event Date: 06/26/2009
Event Time: [EDT]
Last Update Date: 06/26/2009 | Emergency Class: NON EMERGENCY
10 CFR Section:
AGREEMENT STATE
| Person (Organization):
PAMELA HENDERSON (R1DO)
JACK FOSTER (FSME)
|
| This material event contains a "Less than Cat 3" level of radioactive material. | Event Text AGREEMENT STATE REPORT INVOLVING A MISSING TRITIUM SOURCE
The following information was provided by the State of North Carolina via email:
"NC Radioactive Materials [Agency] was contacted this afternoon regarding a lost portable gas chromatograph.
"Notification: June 26, 2009 at 15:00
"Device: Sentex Sensing Technology - Sentex Model Sentor Gas Chromatograph.
"No serial number available.
"SS&D: NY-1210-D-101-B
"Source: Hydrogen-3
"Safety light corp source 58508-3
"No serial number available
"Activity: 150 millicuries
"Manufacturer: Infacon, Inc.
"Manufacturer Address: 2 Technology Way, East Syracuse, NY 10357
"Summary: Licensee's RSO contacted Agency at 15:00 on 6/26/09. Conducted a physical inventory of sources at licensee's address, and could not locate the 150mCi Sentex Gas Chromatograph. Inquired whereabouts of device, and primary Authorized User speculated that the source/device could have been lost as a result of the renovations at the University in 2007-2008."
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. |
| General Information or Other | Event Number: 45168 | Rep Org: CALIFORNIA RADIATION CONTROL PRGM
Licensee: KRAZEN & ASSOCIATES
Region: 4
City: CLOVIS State: CA
County:
License #: 4247-10
Agreement: Y
Docket:
NRC Notified By: KENT PRENDERGAST
HQ OPS Officer: JOHN KNOKE | Notification Date: 06/26/2009
Notification Time: 19:25 [ET]
Event Date: 06/26/2009
Event Time: [PDT]
Last Update Date: 06/26/2009 | Emergency Class: NON EMERGENCY
10 CFR Section:
AGREEMENT STATE
| Person (Organization):
DALE POWERS (R4DO)
JACK FOSTER (FSME)
ILTAB VIA EMAIL ()
MEXICO VIA FAX ()
|
| This material event contains a "Less than Cat 3" level of radioactive material. | Event Text AGREEMENT STATE REPORT - STOLEN TROXLER GAUGE
"The licensee reported a M/D [moisture density] gauge was stolen from the residence of a Krazan and Associates employee. The gauge was a Troxler 3430 portable moisture density gauge, serial number 35729 containing approximately 8 mCi of Cesium 137 and 40 mCi of Americium 241. The gauge was stolen sometime between 5pm on Thursday, June 25 and 6:00 am on Friday, June 26, 2009. The gauge was stolen from the back of an open pickup bed at the employee's residence in Bakersfield, CA. According to the RSO, the gauge was stored in the locked gauge case that was chained to the vehicle frame. The licensee has reported the incident to the Kern County Police and the Kern County Sheriffs Office. The licensee will also be offering a reward in the local newspaper and on Craigslist."
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. |
| General Information or Other | Event Number: 45171 | Rep Org: OHIO BUREAU OF RADIATION PROTECTION
Licensee: ACUREN INSPECTION, INC.
Region: 3
City: DAYTON State: OH
County:
License #: 03320990006
Agreement: Y
Docket:
NRC Notified By: STEPHEN JAMES
HQ OPS Officer: DONG HWA PARK | Notification Date: 06/29/2009
Notification Time: 11:02 [ET]
Event Date: 06/26/2009
Event Time: 11:30 [EDT]
Last Update Date: 06/29/2009 | Emergency Class: NON EMERGENCY
10 CFR Section:
AGREEMENT STATE
| Person (Organization):
ANN MARIE STONE (R3DO)
ANGELA MCINTOSH (FSME)
MONTE PHILLIPS (R3DO)
| Event Text AGREEMENT STATE REPORT - DIFFICULTY RETRIEVING RADIOGRAPHY SOURCE
The following report was received via facsimile:
"Licensee contacted Ohio Department of Health at approx. 3:45 PM on 6/26/09 to report an incident which occurred earlier that day involving the inability to retrieve a radiography source at a job site near Dayton, Ohio. The incident involved a QSA Global Model 880D camera with a 85 Ci Ir-192 source.
"At approximately 11:30 AM and after several unsuccessful attempts to retrieve the source, the radiography crew secured the area around the source and contacted a trained source recovery individual at their Cincinnati office for assistance. This person arrived at the job site at approx. 12:20 PM and assessed the situation.
"The recovery person determined that a flange had fallen on the guide tube during the previous shot, which crushed the guide tube and prevented source retrieval. The shot involved a 90-degree bend on a six-inch pipe and the flange was a scrap piece of material found on site that the crew had used to hold the guide tube in place during the shot. It was further determined that the set-up used by the crew for the shot was not very stable, which contributed to the falling of the flange onto the tube. The recovery person was able to retract the source into the camera at approximately 12:45 PM.
"The licensee determined that there was no exposure to the public or radiography crew as a result of this incident. The radiography crew was reminded to ensure the stability of future shot setups before exposing the source. The guide tube was replaced and work continued."
Ohio report number: OH090006 |
| Fuel Cycle Facility | Event Number: 45179 | Facility: NUCLEAR FUEL SERVICES INC.
RX Type: URANIUM FUEL FABRICATION
Comments: HEU CONVERSION & SCRAP RECOVERY
NAVAL REACTOR FUEL CYCLE
LEU SCRAP RECOVERY
Region: 2
City: ERWIN State: TN
County: UNICOI
License #: SNM-124
Agreement: Y
Docket: 07000143
NRC Notified By: RANDY SHACKELFORD
HQ OPS Officer: DONG HWA PARK | Notification Date: 07/01/2009
Notification Time: 13:12 [ET]
Event Date: 06/30/2009
Event Time: 16:00 [EDT]
Last Update Date: 07/01/2009 | Emergency Class: NON EMERGENCY
10 CFR Section:
70.50(b)(2) - SAFETY EQUIPMENT FAILURE
| Person (Organization):
RANDY MUSSER (R2DO)
EARL EASTON (NMSS)
FUELS OUO (EMAIL) ()
| Event Text SAFETY EQUIPMENT FAILURE OF THE CRITICALITY ALARM SYSTEM
"The public address system (criticality accident alarm) was impaired for a portion of the Building 310 warehouse and a subcontractor trailer. The cause of the impairment was determined to be the result of a contractor drilling into a public address system speaker wire while installing fire protection components in the Building 310 warehouse. This created an electrical short which rendered the speakers inoperable for a portion of the Building 310 warehouse and a subcontractor trailer. The speaker wire was obscured from view by a structural beam. The system was repaired, tested, and placed back into service by 1721 hours (EDT) on 6/30/2009."
The NRC Resident Inspector was notified. |
| Power Reactor | Event Number: 45180 | Facility: OCONEE
Region: 2 State: SC
Unit: [ ] [ ] [3]
RX Type: [1] B&W-L-LP,[2] B&W-L-LP,[3] B&W-L-LP
NRC Notified By: RANDY TODD
HQ OPS Officer: MARK ABRAMOVITZ | Notification Date: 07/01/2009
Notification Time: 16:19 [ET]
Event Date: 05/19/2009
Event Time: 16:09 [EDT]
Last Update Date: 07/01/2009 | Emergency Class: NON EMERGENCY
10 CFR Section:
50.73(a)(1) - INVALID SPECIF SYSTEM ACTUATION
| Person (Organization):
RANDY MUSSER (R2DO)
|
| Unit | SCRAM Code | RX CRIT | Initial PWR | Initial RX Mode | Current PWR | Current RX Mode | | 3 | N | N | 0 | Hot Standby | 0 | Hot Standby | Event Text INVALID FEEDWATER SYSTEM ACTUATION WHILE SHUTDOWN
"On 5-19-09 ONS [Oconee Nuclear Station] Unit 3 was in Mode 3 during startup from a refueling outage. At 1609 EDT the 3A Motor Driven Emergency Feedwater Pump (MDEFWP) unexpectedly started when the control switch was placed in the AUTO2 position as part of system alignment prior to unit startup. Investigation found that the impulse line for the hydraulic oil pressure switch on the operating 3A Main Feedwater Pump was clogged, causing sensed pressure to read below setpoint. Repositioning the control switch enabled the 3A MDEFWP auto start circuitry, which immediately actuated due to the pre-existing false low pressure indication. Several other redundant indications validated that the pressure signal to the pressure switch was false and that actual hydraulic oil pressure remained above the pressure switch setpoint. Although the pressure switch did see low pressure in the impulse line, the actuation is considered invalid since the signal was based on a false reading that did not represent actual plant conditions.
"Therefore this report is being made under 10 CFR 50.73(a)(1) and 50.73 (a)(2)(iv)(A).
"Per NUREG-1022, Rev. 2 the following information is requested:
A) The specific train(s) and system(s) that were actuated. 3A Motor Driven Emergency Feedwater Pump (MDEFWP) which feeds the 3A Steam Generator (SG).
B) Whether each train actuation was complete or partial. The train actuation was considered complete. The pump started per the signal and operated as required/expected in response to the signal. This pump is the only component in the train which receives a specific signal as part of the actuation circuitry.
C) Whether or not the system started and functioned successfully. The 3A MDEFWP started and the system functioned successfully. The EFW control valve (3FDW-315) is set to control at 30 inches (SG startup level) versus 25 inches for Main Feedwater control. Therefore the SG level increased and the train then controlled at approximately 30 inches while an investigation determined the reason for the actuation (as explained above). The 3A MDEFWP was stopped at 2050 EDT and returned to normal status.
"Initial Safety Significance: Due to low feedwater demand at the time, there was little impact on the unit. Since the SG level was maintained above the normal control system setpoint, Main Feedwater flow was automatically reduced to compensate for the EFW flow. The 3A MDEFWP and associated pressure switch/actuation circuit were declared inoperable during pump shutdown and restoration to normal.
"Corrective Action(s): After troubleshooting identified the clogged impulse line, it was isolated and cleared. The 3A MD EFWP and the associated pressure instruments were returned to service."
The licensee notified the NRC Resident Inspector. | |