A new park. That’s what the small town of Wheatley, Ont., is building on the large empty lot at the centre of its downtown core.
Announced at a community party in June, it will take the place of nine buildings, razed following an explosion in August 2021 when hydrogen sulphide, leaking from a long-forgotten gas well, ignited.
The explosion in Wheatley wasn’t unprecedented. A similar event occurred in 1936, in the same place, though it was largely blamed on a gas heater, and again in 1993 — this time a well or crack deep in the earth was likely the cause. And it could happen again.
Gas wells like those found in Wheatley are all over southern Ontario. Most are in quiet rural settings, but they’re also found on the bottom of Lake Erie or in built-up urban areas, like one near the corner of King and Yonge streets in downtown Toronto. Some are visibly marked, but many you wouldn’t even know exist. Some are securely capped — known in industry parlance as being officially “sealed and abandoned” — while others were dug before standards for properly plugging and maintaining them existed, posing a threat to infrastructure, human health and the environment. But making Ontario’s inactive oil and gas wells safe is expensive — and complicated.
Wheatley, Ont., is trying to move on from the explosion that rocked its downtown core in 2021. But the lingering threat of additional inactive gas wells creates a sense of unease. “It feels like it’s never-ending,” one resident says.
Landowners and municipalities carry the cost of properly capping inactive wells without known operators (known as orphan wells) and, even if they can pay for it, researchers say there are likely tens of thousands of old wells we haven’t even located yet. Beyond that, Ontario has nowhere near enough money in its fund for reclaiming new wells that are drilled, should their owners not take responsibility, as many failed to before. While Ontario now requires industry to put down funds for reclaiming active wells, should the company default in some way, the amount is far below the actual cost of capping, according to internal government documents obtained by The Narwhal via freedom of information legislation. So much so that one advisor noted in an email to a provincial oil and gas working group that “the public is led to believe the security will look after the wells and site remediation. This is simply not the case.”
While no one died as a result of the 2021 Wheatley explosion, the heart of the town was partially destroyed. A hundred or more homes and businesses were evacuated while authorities located the source of the leak, demolished the remaining damaged buildings and remediated the site. The process took years, and cost tens of millions of dollars.
As Ontario communities grapple with rising populations and municipal boundaries expand, the problem posed by old gas wells, as well as new ones, grows. And so does the cost to fix it.
Ontario was the epicentre of early fossil fuel development in Canada
Southern Ontario was the early epicentre of what became the national petroleum industry, with commercial drilling for oil and natural gas beginning in 1858 and 1889, respectively. Drilling projects quickly proliferated across the region as private companies and individual landowners sought to capitalize on the region’s fossil fuel resources.
According to a report published in 2023 by the journal Geoscience Canada, 10,000 petroleum wells are estimated to have been operating in Ontario at the turn of the 20th century — but records only exist for 1,500. By 1970, two years before Ontario’s Ministry of Natural Resources was established, some 50,000 wells had been drilled, though records still only exist for 27,000 in total. Given these statistics, the Geoscience report authors conclude “there may be tens of thousands of unrecorded or lost wells in southwestern Ontario.”
At least 50,000 oil and gas wells are estimated to have been drilled in Ontario since the industry began in the mid-19th century. But spotty record keeping means there could be tens of thousands of unrecorded and lost wells throughout the province. Map: Ontario Ministry of Natural Resources
Wells are supposed to be plugged when it’s no longer economically viable to pump out oil or gas. But in the past, in the absence of a permitting process or environmental and safety regulations, materials commonly used to cap and fill wells — wood and gravel, for example — acted as conduits for the movement of fluids to the soil surface. As the capping materials degrade over time, the risk of a leak heightens. It doesn’t help that the metal casings that would make wells more conspicuous were often removed and repurposed to make ships during the Second World War, one expert told the CBC.
The hazards posed by well fluids moving up and leaking from old oil, gas and water wells are many. Hydrogen sulphide — the trigger for Wheatley’s misfortunes — is both highly flammable and poisonous. Oil can contaminate soil, surface water and groundwater, while greenhouse gases like methane contribute to atmospheric pollution. An article published by Environmental Science and Technology in April 2025 found total annual methane emissions from non-producing wells across Canada could be 230,000 tonnes — seven times higher than estimates in the National Inventory Report, the country’s analysis of its greenhouse gas sources and sinks.
Given the poor condition of many plugged wells, and the density of oil and gas wells in Ontario generally, the Geoscience Canada report authors argued “further work is required to locate unreported or lost wells, and to develop new techniques to permanently plug wells to limit gas leakage, reduce greenhouse gas emissions and improve public and environmental safety.”
Plugging Ontario’s gas wells will cost a lot of money
To limit the risk posed by old, inactive wells, they first have to be cleared of whatever scrap material was used to plug them or any debris that covers them, then filled and capped properly with cement. Many factors determine how simple or complex the process is, including how deep the well is and in what state of repair the materials used in the well’s construction are. Hydrocarbon wells can range widely in depth — 400 metres below the lake-bed for gas wells in Lake Erie, for example, or 1,100 metres down for oil wells on land.
The operator is supposed to pay to cap wells that are no longer active. When an operator cannot be identified — which is common, given the age of many drilling projects and lack of historical documentation — the cost falls to the landowner, whether that’s a farmer, a homeowner, a local government or otherwise. And even documented and relatively accessible wells can incur significant costs.
Recognizing the financial burden old wells can pose, Ontario maintains an abandoned works program to financially support landowners.
The program has spent $29.5 million to date to plug 415 wells — an average cost of $71,084 per well. In June 2023, the province announced plans to double the funds. An additional $7.5 million was also allocated to “directly support municipalities in their efforts to reduce risks and enhance emergency preparedness,” over a three-year period. That could mean responding to suspected leaks or, in the worst cases, explosions. Those funds are part of a wider $23.6-million investment in a province-wide strategy for identifying and plugging old oil and gas wells.
The investment is significant, but it’s dwarfed by the problem. At an average cost of $71,000 to plug one well, it would cost more than $700 million to plug 10,000 sites, and that’s just a portion of the old wells in the province.
Ontario’s Ministry of Natural Resources, which houses the petroleum operations section, did not respond to The Narwhal’s questions about securities and well reclamation, nor provide clarification on funding for its inactive well strategy.
Oil and gas wells are found throughout southern Ontario. Most sit in quiet rural settings, such as this active oil well in the Wheatley area.
Brett Authier, a Wheatley-area resident and onshore operations manager with oil and gas company Lagasco, is regularly called in to identify and stop leaks, and contracted to properly plug wells. Authier generally budgets $70,000 for most well-maintained sites. Poorly maintained sites, or those with little-to-no records, are more expensive.
“A lot of the old wells have old fence posts in them, pieces of steel, rock,” Authier said. “You have to drill down through old plugs, and basically start from scratch.” Faulty or degraded well casings also have to be sealed.
The core of Ontario’s old well conundrum, Authier said, stems from a lack of regulation over decades of resource exploitation.
Other provinces, including Saskatchewan and Alberta, have received federal assistance for oil and gas well remediation. The private sector in Ontario has also sought federal remediation funding, with the Ontario Petroleum Institute — a non-profit representing oil and gas companies in the province — requesting the Government of Canada provide $270 million for an Ontario orphan well reclamation program. Detailed in a 2020 letter to then finance minister, Bill Morneau, the institute argued such funding would reflect similar investments made for the remediation of inactive wells in B.C., Alberta and Saskatchewan.
Today, energy companies are required to provide financial assurance that active wells will be properly plugged at the end of their useful life. A proposed bill, the Resource Management and Safety Act, seeks to increase the minister of natural resources’ power to address well-related hazards with the operator’s financial securities. The backgrounder on the bill notes, “If left unaddressed, deteriorating oil and gas wells can create hazards that threaten both public safety and the environment.” The bill was debated in June but has yet to pass, and also includes regulations to allow for underground carbon storage, which critics and opposition MPs have noted could increase the risk of gas leaks.
“If used to address a hazard, the ministry could, with these proposed amendments, draw on a non-compliant operator’s financial security to carry out necessary actions, such as plugging or closing valves,” the bill reads.
However, documents obtained through freedom of information legislation suggest current securities are nowhere near enough to cover capping costs, not to mention additional hazards. The government currently requires between $3,000 and $10,000 in security for wells drilled on land, depending on the depth, and $15,000 for underwater wells.
In October 2023, a provincial oil and gas working group discussed a since–passed regulation that removed exemptions on paying security, as well as a cap on security for operators with multiple wells, according to the documents. Minutes from the meeting notes show Natural Resources Ministry staff expressed that, in terms of securities, the “rationale is to prevent further issues to what we currently have with orphaned wells in the province, [and] to ensure operators have sufficient funds to plug wells.” Another point from ministry representatives states: “Goal is to protect the public and environment, regardless of type of project (e.g., oil and gas, hydrocarbon, other special projects).”
In the same discussion, the Ontario Petroleum Institute voiced concerns on behalf of operators over the requirement for securities to be paid when wells are transferred over to new owners: “There may be no one willing to take over assets, which would limit ability to pass wells on to family.” That requirement was dropped in the final regulation.
As part of the working group discussions, one industry consultant suggested in an October 2023 email that, with the security falling so short of the actual cost of plugging wells, the province should take one of two actions: raise the amount required for well securities, or scrap the requirement altogether.
Removing the requirement for securities, he said, “would save administrative costs for the industry and for the regulator and also communicate to the public the reality of the situation.”
He continues, “I think that most operators are responsible. Compliance with the regulatory requirements should be adequate to ensure operations are conducted safely and in an environmentally responsible manner.”
Neither of those changes appear to have been made in the regulation as of Aug. 28, 2025.
The Ontario Petroleum Institute did not respond to requests for comment on its letter, as well as the issue of securities.
Growing costs and challenges of managing Ontario’s old wells
Back in Wheatley, Howard Gabert, resident and chair of a local taskforce established to spur the community’s recovery, said some 60 to 70 households, plus around 30 businesses, were displaced by the explosion, with another 20 people injured. Some people were unable to access their properties for more than a year, Gabert said, while others found their insurance providers dropping coverage or dramatically raising rates.
Investigators eventually uncovered and remediated three wells. But gas continued to leak. A fourth well was only uncovered and capped in 2024 after the remaining buildings were demolished and removed.
The Ontario government has provided more than $50 million to the community since the explosion in 2021. Funding was used for initial emergency support, investigation and remediation.
Moving forward, Robert Sharon, infrastructure services director for Wheatley’s neighbouring community of Leamington, said the risks wells pose to human and environmental health can complicate development planning. Determining setback limits — how far new constructions must be from wells — is a common dilemma for municipal planners.
Setback limits are required for active wells, Sharon said, but there’s no such regulation for old wells on privately owned land. Municipalities are left to determine what constitutes safe setback distances for new developments. And all of this relies on knowing wells are there in the first place.
The abundance of gas wells throughout southern Ontario, both active and inactive, present challenges for planners and additional complications for the province as it moves forward with allowing carbon storage underground.
“While it may seem logical to be conservative and use, say, the greatest setback for a licensed well of 75 metres, keep in mind that a circle with a radius of 75 metres has a land area of 17,600 metres square, or 4.3 acres,” Sharon said. Since wells are common in already built-up areas, maximizing the distance between wells, people and infrastructure is “incredibly difficult.”
Imagine having to take four football fields worth of space out of Toronto’s Financial District — or such a sizable portion out of a planned subdivision in a smaller municipality.
Wheatley’s roughly 3,000 residents are still trying to put the past four years and the explosion that rocked its small downtown behind them, Gabert said. Canada Day 2025 saw the town gather for Fish Fest — an annual event celebrating the community’s maritime connections through concerts, competitions, a boat parade and car show. Just days before, it was nearly cancelled when hydrogen sulphide gas was detected from a new location not far from the explosion site. Local authorities quickly determined it posed a low risk, but it was jarring, nonetheless.
“Nobody expected this to surface 150 metres away from where the other ones are,” Gabert said. “Now we’re playing whack-a-mole. There’s just another weak spot.”
“It feels like it’s never-ending. But we don’t really have a choice but to press on. … It’s kind of like living under a volcano.”
Updated on Sept. 10, 2025, at 8:53 p.m. ET: This story has been updated to correct a statement that the private sector in Ontario has received federal funding for oil and gas well remediation. Rather, the private sector has requested that funding.
