STP Unit 2 Offline Following Circuit Breaker Malfunction

The STP Nuclear Operating Co. declared an "Unusual Event" at 10:38 a.m. this morning when a circuit breaker malfunctioned, which caused Unit 2 to go offline.

The “Unusual Event” ended at 12:40 p.m. STP said there were no injuries and that the unit was in a stable condition. Unit 1 is unaffected and remains online at 100% power.

“We have an experienced and well-trained team at our facility, and our focus and priority is always on safety," said Ed Halpin, STP president and CEO. "Unit 2 operated as designed this morning when the incident occurred. We have a root cause team working to determine the cause of the issue, and will work to safely and efficiently correct the condition and return the unit to service."    

The “Unusual Event” classification indicated that there was a minor problem at the plant that caused the company to enter into the emergency plan. The company contacted Matagorda County officials and state authorities to inform them of the incident at 10:48 a.m. The company also contacted federal authorities, including the Nuclear Regulatory Commission.

Emergency conditions at nuclear power facilities fall into one of four classifications. In order of least serious to most serious, these are: Unusual Event, Alert, Site Area Emergency, and General Emergency.

Source: STP Nuclear