Event Notification Report for July 23, 2011
U.S. Nuclear Regulatory Commission
Operations Center
EVENT REPORTS FOR
07/22/2011 - 07/23/2011
EVENT NUMBERS
47091
Power Reactor
Event Number: 47091
Facility: PRAIRIE ISLAND
Region: 3 State: MN
Unit: [1] [2] []
RX Type: [1] W-2-LP,[2] W-2-LP
NRC Notified By: GENE DAMMANN
HQ OPS Officer: STEVE SANDIN
Region: 3 State: MN
Unit: [1] [2] []
RX Type: [1] W-2-LP,[2] W-2-LP
NRC Notified By: GENE DAMMANN
HQ OPS Officer: STEVE SANDIN
Notification Date: 07/23/2011
Notification Time: 23:20 [ET]
Event Date: 07/23/2011
Event Time: 19:00 [CDT]
Last Update Date: 08/26/2011
Notification Time: 23:20 [ET]
Event Date: 07/23/2011
Event Time: 19:00 [CDT]
Last Update Date: 08/26/2011
Emergency Class: NON EMERGENCY
10 CFR Section:
50.72(b)(2)(xi) - OFFSITE NOTIFICATION
10 CFR Section:
50.72(b)(2)(xi) - OFFSITE NOTIFICATION
Person (Organization):
ERIC DUNCAN (R3DO)
ERIC DUNCAN (R3DO)
| 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 |
OFFSITE NOTIFICATION DUE TO UNMONITORED RELEASE OF TRITIUM TO SEPTIC SYSTEM
"It was discovered that water containing tritium from a secondary system steam leak has been periodically disposed of via the septic system versus the normally monitored turbine building sump effluent path. The tritium amount was 8.00 E-5 microcuries per milliliter. The tritium sample is consistent with normal secondary plant samples. Since November, 2010, there have been no abnormal tritium results from the septic system. There was also MPA (29.7 parts per million) which is a pH additive.
"The septic system is monitored on a monthly basis but is not a normal path for discharge of equipment related fluid leakage. The steam has been condensed and collected in a 5 gallon pail that is periodically emptied by crew personnel. Management just became aware that there were instances where disposal of the water was to the septic system. This practice has been halted. The steam leak has been active since November of 2010.
"This is being reported due to the potential for being an unusual or abnormal release of radioactive effluent.
"The NRC resident has been informed."
The licensee will also inform state and local agencies of this event.
* * * UPDATE FROM BILL SCHALLER TO DONALD NORWOOD AT 1505 EDT ON 8/26/11 * * *
"This is an update to EN 47091 (Water containing tritium from secondary system leak disposed of via septic system) submitted at 2320 EDT on 7/23/2011.
"The fluid in the septic system at Prairie Island Nuclear Generating Plant is removed from site by a vendor, who transports the fluid to the Red Wing, MN Wastewater Treatment Plant where it is processed prior to being discharged.
"The NRC Resident Inspector has been informed.
Notified R3DO (Passehl).
"It was discovered that water containing tritium from a secondary system steam leak has been periodically disposed of via the septic system versus the normally monitored turbine building sump effluent path. The tritium amount was 8.00 E-5 microcuries per milliliter. The tritium sample is consistent with normal secondary plant samples. Since November, 2010, there have been no abnormal tritium results from the septic system. There was also MPA (29.7 parts per million) which is a pH additive.
"The septic system is monitored on a monthly basis but is not a normal path for discharge of equipment related fluid leakage. The steam has been condensed and collected in a 5 gallon pail that is periodically emptied by crew personnel. Management just became aware that there were instances where disposal of the water was to the septic system. This practice has been halted. The steam leak has been active since November of 2010.
"This is being reported due to the potential for being an unusual or abnormal release of radioactive effluent.
"The NRC resident has been informed."
The licensee will also inform state and local agencies of this event.
* * * UPDATE FROM BILL SCHALLER TO DONALD NORWOOD AT 1505 EDT ON 8/26/11 * * *
"This is an update to EN 47091 (Water containing tritium from secondary system leak disposed of via septic system) submitted at 2320 EDT on 7/23/2011.
"The fluid in the septic system at Prairie Island Nuclear Generating Plant is removed from site by a vendor, who transports the fluid to the Red Wing, MN Wastewater Treatment Plant where it is processed prior to being discharged.
"The NRC Resident Inspector has been informed.
Notified R3DO (Passehl).