Event Notification Report for September 21, 2007
U.S. Nuclear Regulatory Commission
Operations Center
EVENT REPORTS FOR
09/20/2007 - 09/21/2007
EVENT NUMBERS
43654436564365743791
General Information or Other
Event Number: 43654
Rep Org: FLORIDA BUREAU OF RADIATION CONTROL
Licensee: WINGERTER LABORATORIES, INC
Region: 1
City: MIAMI State: FL
County:
License #: 0673-1
Agreement: Y
Docket:
NRC Notified By: CHARLES ADAMS
HQ OPS Officer: JOHN KNOKE
Licensee: WINGERTER LABORATORIES, INC
Region: 1
City: MIAMI State: FL
County:
License #: 0673-1
Agreement: Y
Docket:
NRC Notified By: CHARLES ADAMS
HQ OPS Officer: JOHN KNOKE
Notification Date: 09/21/2007
Notification Time: 13:06 [ET]
Event Date: 09/21/2007
Event Time: 00:00 [EDT]
Last Update Date: 09/21/2007
Notification Time: 13:06 [ET]
Event Date: 09/21/2007
Event Time: 00:00 [EDT]
Last Update Date: 09/21/2007
Emergency Class: NON EMERGENCY
10 CFR Section:
10 CFR Section:
Person (Organization):
PAUL KROHN (R1)
CINDY FLANNERY (FSME)
ILTAB EMAIL
PAUL KROHN (R1)
CINDY FLANNERY (FSME)
ILTAB EMAIL
AGREEMENT STATE REPORT - MISSING TROXLER GAUGE
The State provided the following information via email:
"Licensee called 9/21/07, 1:15 AM and reported that a Troxler gauge [model 3411, s/n 10416] is missing. It was last seen on 9/19/07 during the morning inventory in the locked storage locations along with other gauges. It was not present during the evening inventory 9/19/07. No other gauges are missing. Employees started being interviewed by the RSO on 9/20/07. The storage locks have not been tampered with. It was reported missing to the North Miami PD [report # 07-30026] and this office on 9/21/07. Florida is investigating."
Isotopes were Am-241/Be (40 mCi) and Cs-137 (8 mCi).
Florida Report # FL07-140.
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.
The State provided the following information via email:
"Licensee called 9/21/07, 1:15 AM and reported that a Troxler gauge [model 3411, s/n 10416] is missing. It was last seen on 9/19/07 during the morning inventory in the locked storage locations along with other gauges. It was not present during the evening inventory 9/19/07. No other gauges are missing. Employees started being interviewed by the RSO on 9/20/07. The storage locks have not been tampered with. It was reported missing to the North Miami PD [report # 07-30026] and this office on 9/21/07. Florida is investigating."
Isotopes were Am-241/Be (40 mCi) and Cs-137 (8 mCi).
Florida Report # FL07-140.
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: 43656
Rep Org: OK DEQ RAD MANAGEMENT
Licensee: GLOBAL X-RAY SERVICES
Region: 4
City: TULSA State: OK
County:
License #: OK-15194-02
Agreement: Y
Docket:
NRC Notified By: MIKE BRODERICK
HQ OPS Officer: BILL HUFFMAN
Licensee: GLOBAL X-RAY SERVICES
Region: 4
City: TULSA State: OK
County:
License #: OK-15194-02
Agreement: Y
Docket:
NRC Notified By: MIKE BRODERICK
HQ OPS Officer: BILL HUFFMAN
Notification Date: 09/21/2007
Notification Time: 17:07 [ET]
Event Date: 09/21/2007
Event Time: 15:45 [CDT]
Last Update Date: 09/21/2007
Notification Time: 17:07 [ET]
Event Date: 09/21/2007
Event Time: 15:45 [CDT]
Last Update Date: 09/21/2007
Emergency Class: NON EMERGENCY
10 CFR Section:
10 CFR Section:
Person (Organization):
VIVIAN CAMPBELL (R4)
E. WILLIAM BRACH (FSME)
VIVIAN CAMPBELL (R4)
E. WILLIAM BRACH (FSME)
POTENTIAL OVEREXPOSURE OF RADIOGRAPHER HELPER
The State of Oklahoma received a report from Global X-Ray Services of a high monthly exposure reading based on results from Landauer. The August badge for a radiography helper had an exposure of 5680 mR. Initial interviews with the employee determined that he had no instances where his dosimeter ever read off-scale or his rate meter ever indicated excessive exposure rates. His work record shows that he worked for 24 days in the month of August with I-192 radiographic devices. He worked with various radiographers during the month and there is no current information showing any excessive exposures for any of the radiographers. The employee is relatively new and has been averaging 200 - 300 mR per month exposure prior to the August reading.
Landauer is performing analysis to determine if the dose indicates a 'Static' exposure. Both Global X-Ray and the State are developing follow-up actions at this time.
The State of Oklahoma received a report from Global X-Ray Services of a high monthly exposure reading based on results from Landauer. The August badge for a radiography helper had an exposure of 5680 mR. Initial interviews with the employee determined that he had no instances where his dosimeter ever read off-scale or his rate meter ever indicated excessive exposure rates. His work record shows that he worked for 24 days in the month of August with I-192 radiographic devices. He worked with various radiographers during the month and there is no current information showing any excessive exposures for any of the radiographers. The employee is relatively new and has been averaging 200 - 300 mR per month exposure prior to the August reading.
Landauer is performing analysis to determine if the dose indicates a 'Static' exposure. Both Global X-Ray and the State are developing follow-up actions at this time.
General Information or Other
Event Number: 43657
Rep Org: MPR ASSOCIATES, INC ENGINEERS
Licensee: BASLER ELECTRIC COMPANY
Region: 1
City: ALEXANDRIA State: VA
County:
License #:
Agreement: N
Docket:
NRC Notified By: PAUL DAMERELL
HQ OPS Officer: JOHN KNOKE
Licensee: BASLER ELECTRIC COMPANY
Region: 1
City: ALEXANDRIA State: VA
County:
License #:
Agreement: N
Docket:
NRC Notified By: PAUL DAMERELL
HQ OPS Officer: JOHN KNOKE
Notification Date: 09/21/2007
Notification Time: 18:23 [ET]
Event Date: 09/21/2007
Event Time: 00:00 [EDT]
Last Update Date: 09/21/2007
Notification Time: 18:23 [ET]
Event Date: 09/21/2007
Event Time: 00:00 [EDT]
Last Update Date: 09/21/2007
Emergency Class: NON EMERGENCY
10 CFR Section:
21.21 - UNSPECIFIED PARAGRAPH
10 CFR Section:
21.21 - UNSPECIFIED PARAGRAPH
Person (Organization):
PAUL KROHN (R1)
BRIAN BONSER (R2)
HIRONORI PETERSON (R3)
VIVIAN CAMPBELL (R4)
VERN HODGE PART 21 (NRR)
PAUL KROHN (R1)
BRIAN BONSER (R2)
HIRONORI PETERSON (R3)
VIVIAN CAMPBELL (R4)
VERN HODGE PART 21 (NRR)
PART 21 - DEFECTIVE ANALOG ELECTRONIC CIRCUIT CARD (SBSR AVR)
The SBSR AVR card is manufactured by Basler Electric Company in Highland, Illinois. Basler is a supplier of generator control equipment, including generator excitation systems and protective relays. The company maintained a 10 CFR 50, Appendix B Quality Assurance program until the mid 1990s but is presently a commercial supplier with an ISO 9001:2000 certified quality program.
The basic component is an analog electronic circuit card in Basler voltage regulators used on emergency diesel generators (EDGs) in US nuclear power plants. The Basler SBSR excitation system provides closed-loop control of EDG stator voltage via an automatic voltage regulator (AVR) and an exciter. The AVR is the controller, while the exciter converts the control signal from the AVR to a field voltage that is applied to the EDG field winding. The AVR is an analog assembly. The main component of this assembly is an electronic circuit card that is referred to as the SBSR AVR card.
The SBSR AVR card contains a variety of mounted components. The defect identified within this report deals specifically with the soldered electrical connections between the L1 magnetic amplifier module (magamp) and the card. While there are many Basler SBSR AVR card part numbers, all cards perform the same function and have similar components. Further, all cards utilize the same L1 magamp and all cards mount and electrically connect the L1 magamp in a similar manner.
The nature of the defect is that over a period of many years, cracks can form in the solder joint connections between the L1 magamp and the circuit board. There are nine such solder connections at the L1 magamp, and all nine are susceptible to cracking. Cracks have been observed in five SBSR AVR cards that have been in service at two separate nuclear power plants. Also, another case (at one of the same two plants) exhibited symptoms similar to those exhibited by cards with cracked solder joints, but the card was not inspected for the presence of cracks nor retained. Accordingly, cracks are suspected but not confirmed in this other case.
It has been observed that full circumferential cracks can form. When a full circumferential crack forms, the electrical resistance at the connection can increase significantly and electrical continuity at the connection could be lost.
In four of the six cases, the observed symptom associated with the cracks is that during surveillance testing, the EDG starts and takes longer than specified to reach its rated voltage. The condition is observed to be intermittent, i.e., when the test is repeated the EDG typically starts and meets its time requirement to establish rated voltage. This intermittent nature has made troubleshooting more difficult as the symptom is typically not reproducible. This observation is consistent with the fact that a cracked solder joint may not fully and permanently lose electrical connectivity.
In one of the six cases, the observed symptom was that during surveillance testing, the voltage regulator failed to properly control output voltage of the EDG. The EDG had to be shut down, and it may not have been capable of powering its design basis loads.
In one of the six cases there were no symptoms or deficiencies during surveillance testing. Rather, the cracks were seen during a visual observation.
For SBSR AVR cards that have been supplied by MPR, MPR has not specified maintenance requirements related to inspection or replacement. Accordingly, there are no supplier-specified actions that would ensure that degraded cards are detected or avoided.
The safety hazard is that when electrical continuity is lost at L1 magamp soldered connections, the voltage regulator does not perform as intended, and the EDG could fail to deliver emergency AC power as intended. Analyses and testing by MPR in conjunction with Basler Electric confirmed that, although various symptoms can be observed, loss of electrical connectivity at some combinations of L1 magamp soldered connections could render the voltage regulator unable to control voltage. In such a case, the associated EDG would not be able to provide emergency AC power as intended. Because EDGs are important safety-related components at nuclear power plants that are relied upon for safety-related functions, the cracked solder joints could be a substantial safety hazard.
MPR has provided SBSR systems, including AVR circuit cards and spare AVR cards to the following nuclear plants: Beaver Valley, Millstone, Davis-Besse, Pilgrim, Cooper Nuclear, Ginna.
US Nuclear plants believed by MPR to utilize the SBSR excitation system are: ANO, Beaver Valley, Calvert Cliffs, Cooper, Crystal River, Davis-Besse, Diablo Canyon, Duane Arnold, Farley, Fermi, FitzPatrick, Ginna, Hatch, Indian Point, Kewaunee, McGuire, Millstone, North Anna, Palisades, Peach Bottom, Pilgrim, Prairie Island, Robinson, Salem, Sequoyah, and Vermont Yankee.
For SBSR AVR cards that MPR has supplied, MPR will issue a maintenance bulletin to advise SBSR AVR owners that an inspection and repair program should be established. The inspection program should periodically inspect for L1 magamp solder joint cracks. The inspections should occur on a fuel cycle periodicity after 15 years of service. If cracks are found, the card should be replaced, or the joints repaired by remaking the solder connections.
The SBSR AVR card is manufactured by Basler Electric Company in Highland, Illinois. Basler is a supplier of generator control equipment, including generator excitation systems and protective relays. The company maintained a 10 CFR 50, Appendix B Quality Assurance program until the mid 1990s but is presently a commercial supplier with an ISO 9001:2000 certified quality program.
The basic component is an analog electronic circuit card in Basler voltage regulators used on emergency diesel generators (EDGs) in US nuclear power plants. The Basler SBSR excitation system provides closed-loop control of EDG stator voltage via an automatic voltage regulator (AVR) and an exciter. The AVR is the controller, while the exciter converts the control signal from the AVR to a field voltage that is applied to the EDG field winding. The AVR is an analog assembly. The main component of this assembly is an electronic circuit card that is referred to as the SBSR AVR card.
The SBSR AVR card contains a variety of mounted components. The defect identified within this report deals specifically with the soldered electrical connections between the L1 magnetic amplifier module (magamp) and the card. While there are many Basler SBSR AVR card part numbers, all cards perform the same function and have similar components. Further, all cards utilize the same L1 magamp and all cards mount and electrically connect the L1 magamp in a similar manner.
The nature of the defect is that over a period of many years, cracks can form in the solder joint connections between the L1 magamp and the circuit board. There are nine such solder connections at the L1 magamp, and all nine are susceptible to cracking. Cracks have been observed in five SBSR AVR cards that have been in service at two separate nuclear power plants. Also, another case (at one of the same two plants) exhibited symptoms similar to those exhibited by cards with cracked solder joints, but the card was not inspected for the presence of cracks nor retained. Accordingly, cracks are suspected but not confirmed in this other case.
It has been observed that full circumferential cracks can form. When a full circumferential crack forms, the electrical resistance at the connection can increase significantly and electrical continuity at the connection could be lost.
In four of the six cases, the observed symptom associated with the cracks is that during surveillance testing, the EDG starts and takes longer than specified to reach its rated voltage. The condition is observed to be intermittent, i.e., when the test is repeated the EDG typically starts and meets its time requirement to establish rated voltage. This intermittent nature has made troubleshooting more difficult as the symptom is typically not reproducible. This observation is consistent with the fact that a cracked solder joint may not fully and permanently lose electrical connectivity.
In one of the six cases, the observed symptom was that during surveillance testing, the voltage regulator failed to properly control output voltage of the EDG. The EDG had to be shut down, and it may not have been capable of powering its design basis loads.
In one of the six cases there were no symptoms or deficiencies during surveillance testing. Rather, the cracks were seen during a visual observation.
For SBSR AVR cards that have been supplied by MPR, MPR has not specified maintenance requirements related to inspection or replacement. Accordingly, there are no supplier-specified actions that would ensure that degraded cards are detected or avoided.
The safety hazard is that when electrical continuity is lost at L1 magamp soldered connections, the voltage regulator does not perform as intended, and the EDG could fail to deliver emergency AC power as intended. Analyses and testing by MPR in conjunction with Basler Electric confirmed that, although various symptoms can be observed, loss of electrical connectivity at some combinations of L1 magamp soldered connections could render the voltage regulator unable to control voltage. In such a case, the associated EDG would not be able to provide emergency AC power as intended. Because EDGs are important safety-related components at nuclear power plants that are relied upon for safety-related functions, the cracked solder joints could be a substantial safety hazard.
MPR has provided SBSR systems, including AVR circuit cards and spare AVR cards to the following nuclear plants: Beaver Valley, Millstone, Davis-Besse, Pilgrim, Cooper Nuclear, Ginna.
US Nuclear plants believed by MPR to utilize the SBSR excitation system are: ANO, Beaver Valley, Calvert Cliffs, Cooper, Crystal River, Davis-Besse, Diablo Canyon, Duane Arnold, Farley, Fermi, FitzPatrick, Ginna, Hatch, Indian Point, Kewaunee, McGuire, Millstone, North Anna, Palisades, Peach Bottom, Pilgrim, Prairie Island, Robinson, Salem, Sequoyah, and Vermont Yankee.
For SBSR AVR cards that MPR has supplied, MPR will issue a maintenance bulletin to advise SBSR AVR owners that an inspection and repair program should be established. The inspection program should periodically inspect for L1 magamp solder joint cracks. The inspections should occur on a fuel cycle periodicity after 15 years of service. If cracks are found, the card should be replaced, or the joints repaired by remaking the solder connections.
Power Reactor
Event Number: 43791
Facility: BRUNSWICK
Region: 2 State: NC
Unit: [1] [] []
RX Type: [1] GE-4,[2] GE-4
NRC Notified By: MARK TURKAL
HQ OPS Officer: JOE O'HARA
Region: 2 State: NC
Unit: [1] [] []
RX Type: [1] GE-4,[2] GE-4
NRC Notified By: MARK TURKAL
HQ OPS Officer: JOE O'HARA
Notification Date: 11/19/2007
Notification Time: 10:38 [ET]
Event Date: 09/21/2007
Event Time: 13:10 [EST]
Last Update Date: 11/19/2007
Notification Time: 10:38 [ET]
Event Date: 09/21/2007
Event Time: 13:10 [EST]
Last Update Date: 11/19/2007
Emergency Class: NON EMERGENCY
10 CFR Section:
50.73(a)(1) - INVALID SPECIF SYSTEM ACTUATION
10 CFR Section:
50.73(a)(1) - INVALID SPECIF SYSTEM ACTUATION
Person (Organization):
GEORGE HOPPER (R2)
GEORGE HOPPER (R2)
| Unit | SCRAM Code | RX Crit | Initial PWR | Initial RX Mode | Current PWR | Current RX Mode |
|---|---|---|---|---|---|---|
| 1 | N | Y | 23 | Power Operation | 23 | Power Operation |
INVALID ACTUATION OF EMERGENCY DIESEL GENERATORS
"This telephone notification is being made in accordance with 10CFR50.73(a)(1) to report an invalid actuation of the Emergency Diesel Generators (EDGs) reportable under 10CFR50.73(a)(2)(iv)(A).
"On September 21, 2007, at approximately 1310 EDT, while Operators were in the process of synchronizing the main turbine generator, a Generator Field Overexcitation trip occurred due to a failed transistor on the manual voltage regulator circuit board. This resulted in a primary and backup generator lockout and turbine trip. All four EDG's started and operated as expected. Because electrical power was never lost to the emergency buses and none of the EDGs loaded onto their respective emergency buses, the actuations were considered to be partial. The EDGs were returned to their standby line-up by 1615 on September 21, 2007. Since no actual bus undervoltage condition existed which required the EDG's to start and the start occurred inadvertently as a result of a single component failure, this event has been classified as an invalid actuation.
"This invalid EDG start event was entered into the corrective action program (i.e., NCR 247573)
"Initial Safety Significance Evaluation - The safety significance is considered to be minimal. The EDGs started and operated normally. Offsite electrical power to the Emergency buses was never lost.
"Corrective Actions - The main turbine generator manual voltage regulator circuit board was replaced."
The licensee notified the NRC Resident Inspector.
"This telephone notification is being made in accordance with 10CFR50.73(a)(1) to report an invalid actuation of the Emergency Diesel Generators (EDGs) reportable under 10CFR50.73(a)(2)(iv)(A).
"On September 21, 2007, at approximately 1310 EDT, while Operators were in the process of synchronizing the main turbine generator, a Generator Field Overexcitation trip occurred due to a failed transistor on the manual voltage regulator circuit board. This resulted in a primary and backup generator lockout and turbine trip. All four EDG's started and operated as expected. Because electrical power was never lost to the emergency buses and none of the EDGs loaded onto their respective emergency buses, the actuations were considered to be partial. The EDGs were returned to their standby line-up by 1615 on September 21, 2007. Since no actual bus undervoltage condition existed which required the EDG's to start and the start occurred inadvertently as a result of a single component failure, this event has been classified as an invalid actuation.
"This invalid EDG start event was entered into the corrective action program (i.e., NCR 247573)
"Initial Safety Significance Evaluation - The safety significance is considered to be minimal. The EDGs started and operated normally. Offsite electrical power to the Emergency buses was never lost.
"Corrective Actions - The main turbine generator manual voltage regulator circuit board was replaced."
The licensee notified the NRC Resident Inspector.