Print edition: 
A federal team of inspectors will go to Wolf Creek next week to determine what caused the automatic shutdown and loss of offsite power that occurred at the northeast Kansas site earlier this month, the U.S. Nuclear Regulatory Commission said Wednesday.
The six-member team will stay “as long as it takes to fully understand what happened,” NRC spokeswoman Lara Uselding said.
The NRC declared a “notification of unusual event” – the agency’s lowest of four emergency classifications – when a main generator electrical breaker at the plant near Burlington tripped about 2 p.m. on Jan. 13. That was followed by an unexplained loss of power to an electrical transformer, resulting in the plant’s connection to the electrical power grid to be removed.
Emergency generators automatically started to power safety-related equipment. There were no radiological releases during the shutdown, the NRC said.
About 5 p.m., off-site power was partially restored.
A six-member NRC team will join the two NRC inspectors who are at Wolf Creek fulltime in working on the problem.
An expanded investigative team is used when the NRC “wants to promptly dig deeply into circumstances surrounding an operational event,” said NRC Region IV Administrator Elmo Collins. “We want to make sure that all of the circumstances are well understood in order to prevent a recurrence.”
A written report of the inspection will be issued within 30 days after the inspection is completed.
In March 2011, Wolf Creek was one of three plants in the country that had been targeted for increased oversight by NRC. The plant triggered the attention because of three unplanned shutdowns in 2010.
After Wolf Creek took corrective action and passed a supplemental inspection, the facility was placed back in good standing with the agency in May.
