The Donald C. Cook Unit 2 reactor automatically tripped late Monday evening after a main turbine trip, according to an NRC report. The cause of the trip is still under investigation.
According to the report, the electrical grid is stable and Unit 2 is being supplied by offsite power, and a preliminary evaluation indicates all plant systems functioned normally following the reactor trip. The remains stable in Mode 3 while conducting the post trip review. No radioactive releases were experienced as a result of this event.
The reactor trip comes only three days after the unit was returned to service Saturday following a 38-day period of refueling and maintenance.