How Darlington’s first small reactor reached a construction licence

The original assessment covered a wider proposal

The regulator describes the Darlington project as including up to four new reactors at the existing nuclear site in Clarington. The federal environmental assessment was completed in 2012. The commission revisited its applicability after the operator selected the BWRX-300 design. Source 1

The construction application covered one unit

Ontario Power Generation applied for one construction licence in October 2022. The commission considered it at public hearings in October 2024 and January 2025. The resulting licence covers the first unit and includes site-specific conditions. Source 1

Consultation formed part of the licensing decision

The commission says the licensing decision engaged the Crown’s duty to consult. It concluded that the duty had been met in relation to the decision and directed measures to incorporate Indigenous knowledge and practices into licensed activities and oversight. Source 1

Financing and licensing are separate milestones

The Major Projects Office profile records a June 2026 loan guarantee transaction supporting about CAD 715 million in financing for seven Williams Treaties First Nations to acquire an eventual minority interest. That announcement concerns project ownership and financing. The construction decision describes the scope of authorised work. Source 2 Source 1

Sources

• Canadian Nuclear Safety Commission, first Darlington reactor construction decision backgrounder
• Government of Canada, Darlington New Nuclear Project project profile