Emily Christensen, PG&E’s spokeswoman, said that the control rod P-08, or Papa 08 was raised properly but when lowered it got stuck. The plant is still fully operational and the rod is able to function safely. The rod’s total range of movement is imperfect, Emily said, but emphasized there is no danger to the plant or the public.
The plant officials worry that attempting to fix the rod would cause it to unpredictable drop and shut down the reaction in the core. The control rods are supposed to stop the reaction but only when there is a possible hazard. Michael Peck of the U.S, Nuclear Regulatory Commission, explained when there’s nothing wrong, however, an all-out shutdown would lead to other problems.
“When we look at it from a probabilistic perspective there’s a slight risk that would start something more,” Peck said. According to Peck, the risk is very low and may be a one-in-a-million chance. But in the disaster at Three Mile Island, Peck said, the reactor shutdown inadvertently damaged the nuclear fuel.
In May 2009, the operators will decrease the reactor to half power during routine maintenance on the water-cooling system. The operators will work to fix the malfunctioning rod at that time to lessen the risk of an automatic shutdown. The likely cause of the malfunction is debris which has jammed the control rod’s gears.
