In mid-November, USA fleet members Cook Unit 2 and Hope Creek successfully completed their scheduled refueling outages. As these two plants returned to service, Prairie Island continued its major project to replace its steam generators during its refueling outage.

As part of its refueling outage, Cook completed more than 12,600 maintenance, inspection and equipment modification job activities. This included several activities associated with the plant’s Life Management Project such as the replacement of two feedwater heaters, a new control room annunciator system, replacement of two unit auxiliary transformers and significant transmission switchyard improvements including replacement of a large transformer.

“We completed some complicated large-scale Life Cycle Management projects this outage that will continue to support the safe, reliable and economic operation of the Cook units for many years to come,” said Larry Weber, Cook Senior Vice President and Chief Nuclear Officer. “Cook has been operating extremely well thanks go to our talented employees and the local and regional workers who supplement our workforce.”

At Hope Creek, more than 18,000 work activities were performed. Major work included replacement of three feedwater heaters, inspection and overhaul of a low pressure turbine, maintenance on one of the station’s vital electrical buses as well as maintenance on two of the station’s four emergency diesel generators.

“The tremendous amount of time and effort that was invested by our team to prepare for this outage resulted in overall strong performance,” said Mitch Dior, Hope Creek Outage Manager. “The success we achieved is the direct result of everyone’s commitment to owning their performance by consistently demonstrating the correct behaviors that enabled us to safely and efficiently complete this refueling outage.”

Prairie Island’s refueling outage and steam generator replacement on its Unit 2 continues to progress. The old steam generators have been removed to make way for the replacement steam generators, which have been successfully installed. Prairie Island is one of only a few plants in the nation that has operated its original steam generators for the design life of the plant due to high standards in controlling chemistry, operations and maintenance.

In addition to the steam generator replacement project, Prairie Island has other major work in progress including switchyard upgrades, turbine lube oil purification modification, reactor coolant pump seal replacement, emergency diesel generator repairs, and turbine generator repairs.

“This has been a very ambitious outage for Prairie Island and a significant capital investment for the company,” said Kevin Davison, Site Vice President. “Along with the substantial work to replace the steam generators, there are some major plant upgrades and long-standing equipment reliability issues being eliminated.”

The plant will begin to reload the core later this month and will commence start-up activities to place the unit back online by the end of December.

A welder works on one of the new steam generators at Prairie Island.