The US Nuclear Regulatory Commission has approved the restart of Omaha Public Power District’s Fort Calhoun nuclear station in Nebraska, which has been offline since April 2011.

Restart activities began in mid-afternoon on Tuesday 17 December, and the reactor is expected to reach 100% power within five or six days. Fort Calhoun is designed to operate for around 18-months before it will need to be shut down for refuelling.

The 478 MW Fort Calhoun pressurized water reactor has been offline since an April 2011 refuelling outage in order to correct a ‘variety of concerns with plant equipment, programmes and processes.’

In a 17 December letter to utility OPPD, NRC said that it "has concluded that the plant, people, and processes are ready to support the safe restart of the Fort Calhoun Station."

The conclusion was based on over 23,000 hours of extensive inspections and evaluations to independently review more than 450 restart actions items, ‘major improvements’ the plant’s supporting organizational infrastructure, as well as a number of equipment modifications to improve reliability.

OPPD invests in Fort Calhoun improvements

OPPD has invested in "significant major upgrades to numerous vital systems" in order to bring the Fort Calhoun station back online, according to OPPD president and CEO Gary Gates.

This investment means better protection from flooding and tornadoes or high winds, stronger steam and high pressure lines and enhanced barriers to radiation inside the plant.

Major changes to the plant’s equipment and processes and procedures were overseen by Exelon Generation, the largest nuclear operator in the United States with a fleet of 17 reactors. In 2012, OPPD hired Exelon to run Fort Calhoun for up to the duration of its operating licence, which is due to expire in September 2033.

The Fort Calhoun plant will remain under increased NRC oversight for an undetermined length of time, until the agency determines that the plant’s performance warrants returning it to the normal reactor oversight programme.


Photo: Fort Calhoun (Source: OPPD)