Name of the Project
Darlington Nuclear Generating Station (DNGS) refurbishment project.

Location
Ontario, Canada.

Project Owner/s
Ontario Power Generation (OPG).

Project Description
The DNGS is a four-unit nuclear power plant owned and operated by OPG.

Each of the four units comprises a Candu pressurised heavy water reactor with a net generating capacity of 881 MW providing a combined capacity of 3 524 MW.

The project involves the refurbishment of each of the four DNGS reactors at the facility and continued operation of each reactor for about 30 years.

The project includes defuelling and dewatering of each reactor; replacement of reactor components – fuel channel assemblies and feeder pipes; repair and maintenance, as well as upgrades to balance of plant.

The project further comprises the management of nuclear and non-nuclear waste, including storage of retube waste and transportation of miscellaneous refurbishment low- and intermediate-level radioactive waste.

Each reactor will also be filled with heavy water, and refuelled and restarted.

Potential Job Creation
The refurbishment will create an estimated 8 800 jobs a year during the construction period and preserve 3 000 full-time positions.

Capital Expenditure
Not stated.

Planned Start/End Date
The project is scheduled for completion in 2026.

Latest Developments
Darlington Unit 3 is ready to begin the next stage of its refurbishment – the disassembly – after successful separation of the reactor and its systems from the three remaining operating units at the station.

Workers installed the last bulkhead section on January 6, 2021, to complete a physical protective barrier ten days ahead of the originally planned 44-day schedule.

The installation of the bulkhead, which involved welding together 16 steel panels each weighing more than 5 t, is part of “islanding” – or physically isolating – Unit 3 to create a safe and defined work area for refurbishment and to protect workers and the plant.

To certify islanding is complete, a series of positive and negative pressure tests, called a containment pressure test (CPT), were conducted to verify an airtight seal around the bulkhead.

A successful CPT on January 14 marked the end of the islanding activities on Unit 3 and the start of the next segment of work, the removal series, which will result in the reactor being dismantled. The removal series is scheduled to last 311 days.

Key Contracts, Suppliers and Consultants
GE Power (stator).

Contact Details for Project Information
OPG, email darlingtonrefurb@opg.com.