Operators shut down the reactor at the Palisades nuclear plant in Michigan Thursday to replace a seal on a control rod.
An Entergy spokesman noted the preventative maintenance is unrelated to increased regulatory scrutiny following three recent findings by the Nuclear Regulatory Commission. The Combustion Engineering pressurized water reactor has 45 control rods, and the Holland Sentinel quoted an Entergy spokesman as saying a seal on one of them was showing wear.
The time offline marks a rough start to the New Year for plant management, which will attend conferences with NRC representatives Wednesday to discuss preliminary white and yellow findings from last year. The reactor had five unplanned shutdowns in 2011, according to Michigan Public Radio. Last Tuesday the NRC confirmed a preliminary white finding related to a shutdown in May when, according to the agency, improper greasing of an overspeed trip mechanism contributed to a failure of a turbine-driven auxiliary feedwater pump.
On Wednesday Entergy will have the chance to contest another preliminary white finding regarding a problem with a service water pump in August. They will also address a more serious yellow finding that involves a reactor trip in September caused by a faulty electrical circuit during maintenance. Last week the NRC placed the plant in its “regulatory response” category, which prompts additional inspections from the agency.