Event Notification Report for July 29, 2022
U.S. Nuclear Regulatory Commission
Operations Center
EVENT REPORTS FOR
07/28/2022 - 07/29/2022
EVENT NUMBERS
56023
56023
Power Reactor
Event Number: 56023
Facility: Dresden
Region: 3 State: IL
Unit: [2] [3] []
RX Type: [2] GE-3,[3] GE-3
NRC Notified By: Collin Grischott
HQ OPS Officer: Bethany Cecere
Region: 3 State: IL
Unit: [2] [3] []
RX Type: [2] GE-3,[3] GE-3
NRC Notified By: Collin Grischott
HQ OPS Officer: Bethany Cecere
Notification Date: 07/30/2022
Notification Time: 04:00 [ET]
Event Date: 07/29/2022
Event Time: 22:17 [CDT]
Last Update Date: 07/30/2022
Notification Time: 04:00 [ET]
Event Date: 07/29/2022
Event Time: 22:17 [CDT]
Last Update Date: 07/30/2022
Emergency Class: Non Emergency
10 CFR Section:
50.72(b)(3)(v)(B) - Pot Rhr Inop
10 CFR Section:
50.72(b)(3)(v)(B) - Pot Rhr Inop
Person (Organization):
Peterson, Hironori (R3DO)
Peterson, Hironori (R3DO)
| Unit | SCRAM Code | RX Crit | Initial PWR | Initial RX Mode | Current PWR | Current RX Mode |
|---|---|---|---|---|---|---|
| 2 | N | Y | 100 | Power Operation | 100 | Power Operation |
| 3 | N | Y | 100 | Power Operation | 100 | Power Operation |
RHR CAPABILITY LOST DUE TO SUCTION BAY LEVEL
The following information was provided by the licensee via email:
"At 2217 CDT on 7/29/22, cribhouse suction bay levels were reported less than 501.5 feet due to buildup of grass on bar racks.
"Ultimate Heat Sink (UHS) is INOPERABLE due to Surveillance Requirement 3.7.3.1 not met. ENTER Technical Specification (TS) 3.7.3 condition A (Required Action (RA) A.1 mode 3 in 12 hours, RA A.2 mode 4 in 36 hours). Dresden Lockmaster reports river level normal at 504.89 feet. Commenced trash rake operations to clear grass debris off of intake bar racks.
"At 0135 CDT on 7/30/22, cribhouse suction bay levels were reported at greater than 501.5 feet. Exit TS 3.7.3 condition A. Due to this INOPERABILITY, the system was in a condition that could have prevented the fulfillment of a safety function; therefore, this condition is being reported as an eight-hour, non-emergency notification per 10 CFR 50.72(b)(3)(v)(B).
"There was no impact on the health and safety of the public or plant personnel."
The following additional information was obtained from the licensee in accordance with Headquarters Operations Officers Report Guidance:
The licensee notified the NRC Resident Inspector.
* * * UPDATE ON 7/30/22 AT 1934 EDT FROM COLLIN GRISCHOTT TO BRIAN LIN * * *
"At 1116 CDT on 7/30/22, a repeat condition occurred where cribhouse suction bay levels were reported < 501.5 feet due to buildup of grass on bar racks. Entered TS 3.7.3 condition A (RA A.1 mode 3 in 12 hours, RA A.2 mode 4 in 36 hours). Actions are in-progress to clear grass debris off the intake bar racks.
"Due to this INOPERABILITY, the system was in a condition that could have prevented the fulfillment of a safety function; therefore, this condition is being reported as an eight-hour, non-emergency notification per 10 CFR 50.72(b)(3)(v)(B).
"At 1745 CDT on 7/30/22, cribhouse suction bay levels were reported at >501.5 feet. Exit TS 3.7.3 condition A. The station continues to monitor for intake grass buildup and taking appropriate actions to maintain UHS operability."
The following additional information was obtained from the licensee in accordance with Headquarters Operations Officers Report Guidance:
The licensee notified the NRC Resident Inspector.
Notified R3DO (Peterson).
The following information was provided by the licensee via email:
"At 2217 CDT on 7/29/22, cribhouse suction bay levels were reported less than 501.5 feet due to buildup of grass on bar racks.
"Ultimate Heat Sink (UHS) is INOPERABLE due to Surveillance Requirement 3.7.3.1 not met. ENTER Technical Specification (TS) 3.7.3 condition A (Required Action (RA) A.1 mode 3 in 12 hours, RA A.2 mode 4 in 36 hours). Dresden Lockmaster reports river level normal at 504.89 feet. Commenced trash rake operations to clear grass debris off of intake bar racks.
"At 0135 CDT on 7/30/22, cribhouse suction bay levels were reported at greater than 501.5 feet. Exit TS 3.7.3 condition A. Due to this INOPERABILITY, the system was in a condition that could have prevented the fulfillment of a safety function; therefore, this condition is being reported as an eight-hour, non-emergency notification per 10 CFR 50.72(b)(3)(v)(B).
"There was no impact on the health and safety of the public or plant personnel."
The following additional information was obtained from the licensee in accordance with Headquarters Operations Officers Report Guidance:
The licensee notified the NRC Resident Inspector.
* * * UPDATE ON 7/30/22 AT 1934 EDT FROM COLLIN GRISCHOTT TO BRIAN LIN * * *
"At 1116 CDT on 7/30/22, a repeat condition occurred where cribhouse suction bay levels were reported < 501.5 feet due to buildup of grass on bar racks. Entered TS 3.7.3 condition A (RA A.1 mode 3 in 12 hours, RA A.2 mode 4 in 36 hours). Actions are in-progress to clear grass debris off the intake bar racks.
"Due to this INOPERABILITY, the system was in a condition that could have prevented the fulfillment of a safety function; therefore, this condition is being reported as an eight-hour, non-emergency notification per 10 CFR 50.72(b)(3)(v)(B).
"At 1745 CDT on 7/30/22, cribhouse suction bay levels were reported at >501.5 feet. Exit TS 3.7.3 condition A. The station continues to monitor for intake grass buildup and taking appropriate actions to maintain UHS operability."
The following additional information was obtained from the licensee in accordance with Headquarters Operations Officers Report Guidance:
The licensee notified the NRC Resident Inspector.
Notified R3DO (Peterson).