U.S. Nuclear Regulatory Commission
Event Reports For
06/06/2006 - 06/06/2006
** EVENT NUMBERS **
|Power Reactor ||Event Number: 42020 |
| Facility: POINT BEACH |
Region: 3 State: WI
Unit:   [ ]
RX Type:  W-2-LP, W-2-LP
NRC Notified By: CHARLES STALZER
HQ OPS Officer: JOHN MacKINNON
| Notification Date: 09/27/2005 |
Notification Time: 17:15 [ET]
Event Date: 09/27/2005
Event Time: 10:00 [CDT]
Last Update Date: 06/06/2006
| Emergency Class: NON EMERGENCY |
10 CFR Section:
50.72(b)(3)(ii)(B) - UNANALYZED CONDITION
| Person (Organization): |
DAVID HILLS (R3)
|Unit ||SCRAM Code ||RX CRIT ||Initial PWR ||Initial RX Mode ||Current PWR ||Current RX Mode |
|1 ||N ||N ||0 ||Cold Shutdown ||0 ||Cold Shutdown |
|2 ||N ||Y ||100 ||Power Operation ||100 ||Power Operation |
|POSTULATED FAULTS HAVE ELECTRICAL CURRENT IN EXCESS OF THE MAXIMUM LISTED INTERRUPTING RATINGS. |
"NMC (Nuclear Management Company) has identified certain equipment in the PBNP electrical distribution system that will not assure, under certain conditions, interruption of a three phase bolted fault short circuit. These postulated faults have electrical current in excess of the maximum listed interrupting ratings for designated circuit breakers and associated bus bar bracing. This condition affects the 13.8 Kv, 4.16 Kv, and 480 V power panels, motor control centers (MCCs), and switchgear. Although the probability of bolted faults is considered low, the Point Beach bolted fault analysis is based on the worst case assumption of three phases firmly tied together and grounded. A postulated bolted fault itself would only impact equipment in a single safety train. However, the PBNP Appendix R analysis relies on breaker coordination and fault current interruption to prevent loss of safe shutdown equipment due to common enclosure/power supply associated circuit concerns. The degraded breaker coordination resulting from a bolted fault condition does not satisfy the requirements of the Appendix R safe shutdown analysis.
"This condition is reportable because the PBNP Appendix R analysis is based on the occurrence of a single fire in a single fire area. The postulated condition could result in a loss of safe shutdown equipment functionality beyond that previously analyzed.
"Compensatory measures (i.e., fire rounds - 6 times per day) have been implemented for cases where the unprotected cable length was routed beyond the original fire area. As part of the long-term corrective action, transformer tap setting changes to reduce bus voltages are being evaluated."
The NRC Resident Inspector was notified of this event by the licensee.
* * * UPDATE RECEIVED FROM RYAN RODE TO JOE O'HARA AT 1855 ON 04/06/06 * * *
"This is a supplemental emergency notification based on additional information identified regarding degraded voltage conditions at PBNP. On 09/27/2005 NMC reported a condition where certain equipment in the PBNP electrical distribution system would not assure, under certain conditions, interruption of a three-phase bolted fault short circuit. Licensee Event Report (LER) 266 & 301/2005-005-00 was subsequently submitted on November 18, 2005. The original Event Notification Report was associated with bolted fault conditions that potentially resulted in
additional unanalyzed fire losses due to direct fire damage or uncleared faults on associated circuits. The synopsis of the LER addressed these issues, and also identified:
"1. A non-conservative Technical Specification for degraded voltage time delay relay settings and their setting tolerance range in calibration procedures that could have resulted in certain safety system motors and switchgear tripping on overcurrent. Such an event could have prevented the fulfillment of the motors' safety function to mitigate the consequences of an accident.
"2. Under a design basis loss of coolant accident concurrent with a reduced voltage condition, safety-related motors and switchgear may trip their protective devices on overcurrent without the degraded voltage relays being actuated. Affected equipment included certain safeguards 480V AC switchgear, 480 V AC motor control centers, both auxiliary feedwater pump motors, and one component cooling water pump motor.
"Corrective actions for the above issues included placing calibration procedures on administrative hold, implementation of compensatory measures consisting of fire rounds for affected zones, and administrative controls to assure that a more restrictive limit for the degraded voltage allowable value was in place for the affected Technical Specification (s), as well as implementing administrative controls on the management of 480 V loads.
"Long-term corrective actions are evaluation and implementation of analytical changes resulting from the completed analysis, plant modification changes as needed to address minimum bus voltage and submittal of a license amendment request.
"Additional reviews into the extent of condition of this issue have revealed additional potential concerns associated if a station battery charger load test is conducted under reduced or degraded grid voltage conditions. If a battery charger load test is conducted during a degraded grid voltage condition and a loss-of-coolant accident occurs with a coincident safety injection signal but a loss of off-site power does not occur, the battery chargers are not stripped from their alternating current supply. The additional potential electrical load on the AC supply has not been analyzed.
"Compensatory measures, in the form of administrative controls associated with battery charger testing, are being implemented. A supplement to LER 266(301)/2005-005-00 will be submitted.
"The senior resident inspector has been informed of this supplemental report."
Subsequent conversations between the Headquarters Operations Officer and the Shift Manager and Shift Technical Advisor at Point Beach have confirmed that this is not an "emergency" notification as quoted in the first paragraph of the event update. This is an event notification only.
R3DO (Stone) notified.
* * *UPDATE RECEIVED FROM ROBERT BLACK TO PETE SNYDER AT 1847 EDT ON 06/05/06 * * *
"On April 6, 2006, NMC provided a supplemental notification to EN# 42020 regarding a condition where certain equipment in the PBNP electrical distribution system would not assure, under certain conditions, interruption of a three-phase bolted fault short circuit. The supplemental notification resulted from additional reviews into the extent of condition of this issue, which indicated additional potential concerns associated with a station battery charger load test being conducted under reduced or degraded grid voltage conditions.
"A subsequent evaluation of this supplemental condition concluded that its significance is minor.
"The April 6, 2006, supplemental notification concerned 480 VAC vital bus loading due to battery charger load during charger testing and battery charger load while recovering a battery after battery discharge testing conducted under reduced or degraded grid voltage condition. The potential impact of this testing was evaluated to be associated only with the D-109 station battery charger and not several chargers as originally determined. An evaluation of the risk significance of this issue indicates that because of the combination of simultaneous events that would need to occur, the significance is minor. Because of the minor risk significance and that the issue concerns only a single piece of equipment (D-109 station battery charger), the guidance in NUREG-1022 indicates that this condition does not meet the reportability criteria in 10 CFR 50.72(b)(3)(ii)(B). Therefore, the supplemental notification made to EN #42020 on April 6, 2006, is hereby retracted. The underlying condition will continue to be addressed through the plant's corrective action process."
The licensee notified the NRC Resident Inspector. Notified R3DO (M. Phillips).
|General Information or Other ||Event Number: 42614 |
| Rep Org: CALIFORNIA RADIATION CONTROL PRGM |
Licensee: TREADWELL AND ROLLO
City: San Francisco State: CA
License #: CA 5917-38
NRC Notified By: VICTOR ANDERSON
HQ OPS Officer: BILL HUFFMAN
| Notification Date: 06/01/2006 |
Notification Time: 16:50 [ET]
Event Date: 06/01/2006
Event Time: 11:55 [PDT]
Last Update Date: 06/02/2006
| Emergency Class: NON EMERGENCY |
10 CFR Section:
| Person (Organization): |
BLAIR SPITZBERG (R4)
JOSEPH HOLONICH (NMSS)
ILTAB (E-MAIL) ()
MEXICO (E-MAIL) ()
| This material event contains a "Less than Cat 3" level of radioactive material. |
|AGREEMENT STATE REPORT - CALIFORNIA - STOLEN MOISTURE DENSITY GAUGE |
The State of California reported that a moisture density gauge (make, model, and serial number unknown at this time) was stolen from a vehicle used by the licensee. The details and circumstances of the theft are not presently known by the State. An inspector will be sent to the licensee tomorrow to conduct a detailed investigation. The licensee has notified the San Francisco Police Department.
* * * UPDATE FROM CALIFORNIA (HEWADIKARAM) TO HUFFMAN AT 1355 EDT ON 6/02/06 * * *
The State provided the following information via facsimile:
"On 06/01/06, the RSO at Treadwell & Rollo called the RHB (California Radiologic Health Branch) -Sacramento office to report that one of their CPN moisture, density gauges was stolen from a vehicle parked in San Francisco. The NRC operational center was informed of the Incident via telephone on the same day of the incident by RHB. On 06/02/06 RHB-Richmond office contacted the RSO and learned the following:
"The CPN gauge Model MC3, S/N M340107275 containing 10 mCi of Cs-137 and 50 mCi of Am-241 was stolen from a vehicle (SUV) parked in San Francisco near the resident of a Treadwell & Rollo employee. The location was in the vicinity of 7th and Natoma streets in San Francisco. On 05/31/06, the employee returned home from a job site around 10:00 pm and left the gauge in the back of the vehicle without returning it back to their storage location in San Francisco. He noticed that the gauge was stolen when he returned to the vehicle around 7:00 am on 06/01/06. The gauge was stored in the back of the SUV with two locks on the Type A container and covered with a tarp. It was not clear whether the gauge was chained to the vehicle. The vehicle was broken into through the window and the gauge was stolen by cutting the two clasps of the Type A container above the locks. RSO will be providing photographs of the Type A container. RSO immediately notified SFPD of this incident. He had posted a reward for $ 1000.00 on the Craig's list and this reward will also appear In the San Francisco Chronicle on 06/03/06. The RHB will be investigating this incident and a notice of violation will be issued to the licensee for the items of non compliance."
The R4DO (Whitten) and NMSS EO (Morell) were notified. The update was also sent to ILTAB and Mexico via E-mail.
CA Report Number 06/01/06.
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.