Event Notification Report for October 20, 2001
U.S. Nuclear Regulatory Commission
Operations Center
EVENT REPORTS FOR
10/19/2001 - 10/20/2001
EVENT NUMBERS
38410
Power Reactor
Event Number: 38410
Facility: THREE MILE ISLAND
Region: 1 State: PA
Unit: [1] [] []
RX Type: [1] B&W-L-LP,[2] B&W-L-LP
NRC Notified By: JOHN SCHORK
HQ OPS Officer: BOB STRANSKY
Region: 1 State: PA
Unit: [1] [] []
RX Type: [1] B&W-L-LP,[2] B&W-L-LP
NRC Notified By: JOHN SCHORK
HQ OPS Officer: BOB STRANSKY
Notification Date: 10/20/2001
Notification Time: 19:25 [ET]
Event Date: 10/20/2001
Event Time: 16:00 [EDT]
Last Update Date: 10/20/2001
Notification Time: 19:25 [ET]
Event Date: 10/20/2001
Event Time: 16:00 [EDT]
Last Update Date: 10/20/2001
Emergency Class: NON EMERGENCY
10 CFR Section:
50.72(b)(3)(ii)(A) - DEGRADED CONDITION
10 CFR Section:
50.72(b)(3)(ii)(A) - DEGRADED CONDITION
Person (Organization):
R1 IRC TEAM MANAGER (R1)
R1 IRC TEAM MANAGER (R1)
| Unit | SCRAM Code | RX Crit | Initial PWR | Initial RX Mode | Current PWR | Current RX Mode |
|---|---|---|---|---|---|---|
| 1 | N | N | 0 | Refueling | 0 | Refueling |
DEGRADED STEAM GENERATOR TUBE FOUND DURING EDDY-CURRENT INSPECTION
"At 1600 hours on Saturday, October 20, 2001 as a result of tube eddy current inspections performed during the 1R14 outage, TMI-1 determined that at least one tube in the 'B' OTSG was seriously degraded. Inspection of the tube found that the tube had been mechanically damaged to the extent of approximately 90% through wall thickness by an adjacent plugged tube that had apparently severed during the last operating cycle.
"Primary to Secondary leakage was very low throughout the last operating cycle, well below Technical Specification limits. The current condition of the tube is such that engineering judgment is that the tube would not have had sufficient strength to meet all of the structural integrity criteria described in NUREG 1022, Rev. 2.
"The 'B' OTSG is currently inoperable with both the upper and lower primary manways removed. OTSG tube inspections are in progress. Additional testing and inspection will be conducted. Structural integrity of the inservice OTSG tubes will be confirmed prior to restart. The extent of the condition discovered and the cause of the condition will be addressed in the followup licensee event report that will be submitted in accordance with 10 CFR 50.73(a)(2)(ii)."
The NRC resident inspector has been informed of this notification by the licensee.
"At 1600 hours on Saturday, October 20, 2001 as a result of tube eddy current inspections performed during the 1R14 outage, TMI-1 determined that at least one tube in the 'B' OTSG was seriously degraded. Inspection of the tube found that the tube had been mechanically damaged to the extent of approximately 90% through wall thickness by an adjacent plugged tube that had apparently severed during the last operating cycle.
"Primary to Secondary leakage was very low throughout the last operating cycle, well below Technical Specification limits. The current condition of the tube is such that engineering judgment is that the tube would not have had sufficient strength to meet all of the structural integrity criteria described in NUREG 1022, Rev. 2.
"The 'B' OTSG is currently inoperable with both the upper and lower primary manways removed. OTSG tube inspections are in progress. Additional testing and inspection will be conducted. Structural integrity of the inservice OTSG tubes will be confirmed prior to restart. The extent of the condition discovered and the cause of the condition will be addressed in the followup licensee event report that will be submitted in accordance with 10 CFR 50.73(a)(2)(ii)."
The NRC resident inspector has been informed of this notification by the licensee.