1. Last Wednesday morning at a time not specified in the Event Report, a Control Room Boundary door failed to latch at the Millstone nuclear power plant in Connecticut. The report indicated that the incident was associated with the Unit 2 reactor. The door was repaired at 5:52 on Wednesday morning.
The failure to specify when the incident began is potentially significant because of something which occurred Tuesday afternoon at the plant. Millstone reported to the NRC that shortly after 1 PM, the radiation stack monitor for Unit 2 was removed from service for planned maintenance. The Event Report estimated that the monitor would be out of service for eight hours.
Because of the failure to identify when the radiation stack monitor was returned to service and the failure to say when the Control Room Boundary door failed to function, we don’t know if the monitor was out of service when Unit 2 lost containment.
2. And late Wednesday night, the Nine Mile Point nuclear power plant in New York had a momentary loss of containment due to both doors in the Reactor Building Airlock being open at the same time.