Cracked pipe caused Palisades shutdown

COVERT TOWNSHIP, Mich. (WOOD) - A preliminary report on the leak that caused the most recent shutdown at the Palisades nuclear power plant has been released.

The Nuclear Regulatory Commission said in a Monday Internet news conference that it is still trying to understand what caused the August leak in a pipe involved in controlling one of the 45 rods that regulate the nuclear reactor. 

The NRC said it found five cracks in the pipe, one of which had spread all the way through the pipe and was leaking radioactive cooling water back into the system.

There was no release outside the containment.  

The company shut down the plant to replace the part. It also did ultrasound tests on another eight of the 45 control rod drive housings and found no more cracks.

The NRC still trying to figure out why that pipe leaked. It might have something to do with that specific control rod, which had an alignment problem years ago.

Palisades has been the recipient of extra regulatory attention because of continuing problems.