Diablo Canyon nuclear power plant reduced the Unit 1 reactor to 50 percent power at about 3 p.m. Monday to perform necessary work on a feedwater pump, according to Pacific Gas & Electric Co. spokesman Tom Cuddy. The Unit 2 reactor continues to operate safely at full power, he said in a news release.
"PG&E made the decision to ramp Unit 1 to 50 percent power after one of two main feedwater pumps malfunctioned," according to the news release. "Main feedwater pumps are part of the non-nuclear, steam side of the plant. Their purpose is to safely increase the pressure of water high enough to enter the steam generator. In addition to the two main feedwater pumps, there are three backup auxiliary feedwater pumps."
Cuddy said that Unit 1 is in safe condition and will be restored to full service after work is complete. The news release did not estimate when that might be. PG&E said it informed the U.S. Nuclear Regulatory Commission and appropriate local and state officials.