The Clinton Nuclear Generating Station is located near Clinton, Illinois. It is a General Electric Generation II boiling water reactor with a one thousand megawatt generation capacity. It was built by Illinois Power and put into operation in 1987 with a forty year operating license until 2026.The plant owners also own a five thousand acre cooling reservoir, most of which is open for recreational use. In 1999, Exelon bought the power plant from Illinois Power for forty million dollars.
The population in the NRC plume exposure pathway zone with a radius of ten miles around the plant contains about fifteen thousand people. The NRC ingestion pathway zone with a radius of fifty miles around the plant contains about eight hundred thousand people. The estimated risk of an earthquake that could damage the plant is very low.
In April of 1996, failure of an electrical transformer caused an automatic shutdown of the reactor. The reactor was maintained in what is known as a hot standby condition because that would reduce the time that the reactor would have to be offline. This put a severe strain on a seal in the recirculating pump. In June of 1996, the reactor was shut down again and placed in a hot standby mode. They could have used this shutdown to find and fix the seal in the pump but they did not. Consequently, in September, the plant operators had to work to fix the pump seal which was leaking. The measures that they took deviated from the correct and safest procedures required in such circumstances. The reactor was allowed to operate for several extra hours even though its condition mandated a shutdown which was eventually accomplished.
When the NRC sent in a team of inspectors to investigate the improper responses to the problem with pump seal, many other problems were found. The operators of the plant worked on fixing the list of problems and notified the NRC that they were ready to restart the reactor in August of 1997. The next day, a circuit breaker broke down at the reactor. The NRC which had been ready to grant the restart cancelled permission, partly because they had just fined the operators of the plant for having problems with the circuit breakers. A major finding of the NRC was that there was not a sufficient focus on safety at the Clinton reactor. The problems at Clinton and six other reactors in 1997 prompted the NRC to change their processes for plant inspections.
In 1997 and 1998, there were multiple repairs, attempts to restart the reactors and multiple inspections by and fines by the NRC. The NRC found numerous violations of proper procedures, many necessary repairs and changes at the reactor, serious problems with staff training and insufficient concern with safety in general. It took two more years of work on the reactor before the NRC was ready to grant permission for a restart. Finally in 1999, the operators at Clinton had cleared the backlog of changes required by the NRC and the reactor was restarted after been out of service for over two year.
