The Darlington nuclear power station (Photo: OPG)Ontario Power Generation (OPG) has completed its defuelling campaign at Darlington 3 ahead of schedule, in preparation for the next phase of the Darlington Refurbishment Project, the utility announced last week.

“Once again, the Darlington Fuel Handling team has demonstrated their knowledge, skills and expertise, defuelling unit 3 safely and with quality ahead of the targeted completion date,” said Steve Gregoris, senior vice president at Darlington NPP.

Defuelling is scheduled as a 90-day campaign and involves the remote-controlled removal of 6240 fuel bundles from the reactor. These are then placed in water-filled fuel bays, where they remain in safe storage for up to 10 years.

With Darlington 3 defuelling now complete, OPG and its project partner, CanAtom Power Group, have begun to prepare the reactor for disassembly, a series of work that starts with Islanding. Subo Sinnathamby, senior vice president, Nuclear Refurbishment, explained: “Islanding is how we create a safe and defined work area for refurbishment, protecting workers and the plant. Over the course of 55 days, we’ll separate the unit being refurbished from operating units by implementing controls and installing steel bulkheads.”

Though OPG has already refurbished and returned Darlington 2 to service, the project team does not see refurbishment of the next units as simply a repeat of the first.

“The benefit of having already refurbished one unit is the ability to apply that direct experience to the remaining work,” said Sinnathamby. “We're making sure to build on our success by applying more than 4000 lessons learned to the plans and preparations for the refurbishments of units 3, 1 and 4. And we’ve already started to see efficiency gains in schedule and quality performance.”

The four-unit Darlington Refurbishment Project is scheduled for completion by 2026.


Photo: The Darlington nuclear power station (Photo: OPG)