PPL shut down unit 2 at its Susquehanna nuclear plant over the weekend after indications of additional turbine blade cracking that has bedeviled both of the Pennsylvania reactors in recent years.
Vibration data from equipment installed to monitor the blades prompted operators to take unit 2 offline Saturday, according to a PPL release. Crews will inspect the blades and conduct other maintenance tasks during the outage. The company said monitoring data indicated "a few turbine blades may have developed small cracks." PPL did not estimate how long the outage might last, and the reactor was offline as of Monday morning. Unit 2 was last shut down for blade inspections in late June.
Replacement blades installed at unit 1 earlier this year have so far reduced the vibration that causes the cracking. The same type of blades will be installed at unit 2 during its next regular refueling outage in the spring of 2015.