Suppose you’re driving down the freeway and your car suddenly loses power and the airbags deploy. You call a tow truck and have your car towed to a garage. Two hours later, the mechanic tells you that there is nothing wrong with your vehicle, and that you must have done something that caused the car to lose power.
That’s not far from what happened to Unit 2 at New York’s Nine Mile Point nuclear power plant yesterday evening. Control room operators received an indication that the Alternative Rod Insertion activated, resulting in an automatic reactor scram from 100 per cent power. As a result of the scram, the Reactor Core Isolation Cooling system activated.
There are no indications at this time that there were any problems with the reactor. Early indications are that there may have been a maintenance error: “Prior to the event, maintenance personnel were working in the vicinity of a reactor vessel level instrumentation rack and may have agitated the common drain line of the transmitters.”
One possible training solution: Patiently explain to workers the necessity for paying attention. Perhaps a sign that says: “When working in the vicinity of the reactor vessel level instrumentation rack, please do not agitate the common drain line of the transmitters. Thank You!”