OAK HARBOR, Ohio - Eight more control-rod-drive mechanism nozzles atop Davis-Besse's nuclear reactor head have indications of cracks or flaws, bringing the number needing repair to 24, FirstEnergy Corp. said Monday.
That's more than one third of the head's 69 nozzles.
The utility said its best-case scenario for restarting the plant, idle since Feb. 28 is now sometime in July.
The discovery of eight more flawed nozzles came during a final round of testing, one that used electromagnetic currents. Four nozzles initially were found to have problems until ultrasonic tests revealed another eight. The number was then bumped from 12 to 16 after additional testing. Now it's up to 24, FirstEnergy Corp. spokesman Todd Schneider said.
The flaws were in the early stages of becoming cracks, many too small to be seen. Only one nozzle developed a through-wall crack large enough to leak radioactive coolant, Mr. Schneider said.
Davis-Besse's reactor head was built years ago for a nuclear plant in Midland, Mich., that was never completed. It went into service six years ago at Davis-Besse. Officials remain puzzled why the device, built to last decades, had problems with its nozzles so quickly.
The utility, the Nuclear Regulatory Commission, and the U.S. Department of Energy are doing separate root-cause reports. They are expected to be discussed with the public at a meeting has yet to be scheduled.41.50821 -83.14501