In early 2026, OPG began drilling 40 boreholes at Ontario’s Wesleyville site. Now, the tests are assessing land that could eventually host up to 10,000 MW of nuclear power

In Ontario, a huge nuclear proposal is still only a proposal, and the first real test is happening underground. Ontario Power Generation has begun drilling 40 boreholes at the long-held Wesleyville site near Port Hope to understand whether the land could support as much as 10,000 megawatts of nuclear capacity.

No reactor has been selected and construction has not been approved. For now, engineers are studying the rock, groundwater and surrounding environment before the project can move any further, as per a report by AutoNotion.

What is being tested at Wesleyville?

The 1,300-acre property sits on the Lake Ontario shoreline, about four miles west of Port Hope. Some of the boreholes are reaching 394 feet, or 120 meters, into the ground.

The drilling forms part of the federal impact assessment for the proposed New Nuclear at Wesleyville Project. The cores will help engineers understand the strength of the bedrock, how groundwater moves through the site and whether the ground could support reactor buildings over a potential 78-year operating life.

The work is being carried out with E.S. Fox, the Indigenous-owned Voyageur Services and other local companies. According to inSauga, the borehole campaign covers 40 locations at depths ranging from 60 to 120 meters and is expected to finish before the end of summer.

The site is also being examined beyond the rock. OPG teams are surveying vegetation, birds and wildlife, while carrying out aquatic and surface-water studies along with archaeological, traffic and socio-economic assessments. Drone surveys and monitoring equipment are also being used.

Why has Wesleyville been waiting for so long?

The land has been associated with electricity generation for more than 50 years. Ontario Hydro, which preceded Ontario Power Generation, began building an oil-fired power station at Wesleyville during the 1970s. The project never produced electricity. The 1979 oil shock and a recession brought the development to a halt.

Rather than sell the property, OPG retained it. Today, the site already has access to transmission lines, a rail line, highways and Lake Ontario, which can provide cooling water.

OPG has identified space for possible nuclear stations on both the eastern and western sections of the property. The same site that once waited for an oil-fired plant could therefore become the location of a far larger nuclear proposal.

How large could the nuclear project become?

The proposed capacity is up to 10,000 megawatts, a figure that would make Wesleyville larger than Ontario’s Bruce nuclear station if fully built.

Bruce operates eight reactors with about 6,400 megawatts of capacity and supplies roughly 30% of Ontario’s electricity. By comparison, the three reactors at Nine Mile Point and FitzPatrick near Oswego total about 4,050 megawatts and provide enough electricity for roughly 2 million homes.

Ontario says the Wesleyville project could support 10,500 jobs across the province, including 1,700 in Port Hope, and contribute C$235 billion to the provincial GDP over its lifespan.

“This agreement is an important step forward as we build the world’s largest nuclear station, creating over 10,000 good-paying jobs and reliable power for up to 10 million homes. We express thanks to Port Hope for the partnership with OPG, as we work together to boost both the local and Canadian economy, with over 90 per cent of nuclear investment stamped with Made in Canada,” Ontario Energy and Mines Minister Stephen Lecce said when OPG and Port Hope signed their agreement in February, as per a news release by Ontario government.

The agreement, however, is a memorandum of understanding. Port Hope has emphasized that it is not a host agreement and does not commit the municipality to hosting the project.

When could Wesleyville actually move ahead?

The regulatory process is still at an early stage. OPG submitted its Initial Project Description to the Impact Assessment Agency of Canada on January 12, 2026. In April, the project was referred to a review panel, with the assessment being conducted jointly with the Canadian Nuclear Safety Commission.

The Impact Assessment Agency formally began the assessment on July 10 and provided OPG with guidelines for its next major submission.

OPG now has up to 1,095 days to prepare its Impact Statement, covering the project's potential effects on the land, water, fish and surrounding communities. The agency's registry had already received 894 public comments.

Several reactor technologies remain under consideration. OPG has mentioned a possible in-service date in the 2040s, but that remains dependent on the lengthy assessment and future decisions.

For now, the 40 boreholes are doing something much more basic. They are asking whether the ground itself is suitable.

FAQs

Why is OPG drilling at Wesleyville?
To test the rock and groundwater before considering nuclear development.

How much nuclear capacity could the site hold?
Up to 10,000 megawatts, according to the proposal.