Southwestern Ontario’s long history of oil and gas development left behind a hidden environmental legacy: thousands of old, orphaned, or poorly documented wells, many of which were drilled before modern abandonment standards existed. Researchers have noted that Ontario may have tens of thousands of unrecorded or “lost” wells, and that improperly plugged wells can become pathways for brine, natural gas, oil, and hydrogen sulphide to migrate from the subsurface to the surface. That creates risks not only for landowners and nearby communities, but also for future subsurface energy projects.
This is why the removal of residual hydrocarbons from otherwise abandoned wells should be understood as an environmental and public safety benefit, not merely a technical step in project development. Where legacy wells contain trapped hydrocarbons, deteriorated well materials, or poor historical plugs, they can pose ongoing risks: fugitive emissions, odours, groundwater impacts, fire or explosion hazards, and uncertainty about subsurface integrity. Cleaning, assessing, and properly preparing these wells reduces those risks in a practical and measurable way.
Bedrock’s compressed air energy storage (“CAES”) project offers an opportunity to reframe the issue. CAES is often discussed as a clean-energy storage technology because it can help store surplus electricity and make intermittent renewable generation more useful. Bedrock has described Ontario’s geology as well-suited to CAES and has framed the technology as a way to reduce wasted energy while supporting the province’s energy transition. But the project’s value is not limited to what happens after it begins storing air. There is also value in the preparatory work itself.
Before a site can responsibly support a subsurface energy project, legacy risks must be identified and addressed. Removing residual hydrocarbons, evaluating old wells, and ensuring that pathways are properly managed can convert a dormant liability into a safer, better-understood asset. In that sense, Bedrock’s site preparation helps clean up the historical footprint of fossil fuel development while enabling a lower-carbon use of the same regional geology.
This is particularly important because Ontario now recognizes CAES in porous rock as an activity requiring regulatory oversight under the Oil, Gas and Salt Resources Act. The province has stated that oversight of CAES in porous rock is intended to improve public and environmental safety while providing clarity for the energy storage industry. Ontario has also emphasized the importance of financial security for wells so that funds are available for plugging at the end of a well’s useful life, reducing environmental and safety risks from future orphaned wells.
Properly handled, Bedrock’s project can therefore demonstrate a broader principle: the energy transition should not ignore legacy fossil fuel infrastructure. It should remediate it, secure it, and where appropriate, repurpose the geology beneath it for cleaner public benefit. Removing residual hydrocarbons from abandoned wells is not just about preparing a CAES site. It is about reducing emissions, improving safety, protecting groundwater, and showing that new energy infrastructure can repair part of the environmental inheritance left by older energy systems.
