ONTARIO — Site preparation is well underway at the Darlington nuclear station, where Ontario Power Generation (OPG) is building the country’s first grid-scale small modular reactor (SMR) — and the first of its kind in the G7.
“OPG and Ontario are now building the foundation for not just Canada’s first SMR, but also future SMRs in this country and beyond,” said Dragan Popovic, OPG’s Senior Vice-President of SMR Execution. “We are doing this with the help of skilled Ontarians and local communities. Our team, our people, and our partners are now building the capacity and the model for new reliable, low-carbon nuclear power for our future.”
Since the province approved construction in May, OPG and skilled trades from across Ontario have been working on key structural components of the reactor building. Off-site production of diaphragm plate steel composite modules — critical elements of the reactor’s foundation — is underway, with the first assemblies already arriving at Darlington. Once excavation of the 35-metre-deep reactor shaft is complete, cranes will lower the foundation into place.
Several support facilities have also been completed this summer. The on-site pre-assembly building and the fabrication building, which will house final assembly of modular reactor components, are now operational. Foundation work for the radiation waste building and control and service structures is finished as well.
Excavation continues on the reactor building shaft, forebay shaft, and condenser cooling water launch shaft. Meanwhile, grading for three additional SMR units has been finalized, setting the stage for future expansion.
A massive tunnel boring machine, delivered this summer, will soon begin carving out the cooling water path needed for the fleet of four planned SMRs.
Darlington’s SMR is expected to be a model for future nuclear projects in Canada and abroad, with refurbishing of the existing station still on track for completion in 2026.