The site of the explosion in Wheatley, Ontario from an apartment on Talbot Street. Debris is still scattered on the tops of nearby buildings. The mat in the empty space is covering one of the suspected wells where gas escaped, causing an explosion in August 2021 that destroyed multiples buildings on that spot. The blue piping is part of remediation of other wells found on the site.Melissa Tait/The Globe and Mail
Almost one year ago, an explosion in Wheatley highlighted a widespread and potentially deadly problem in Southwestern Ontario, home to Canada’s oldest oil and gas industry.
Though an investigation into the exact cause of the blast still isn’t complete, it’s suspected that a mix of hydrogen sulfide (H2S) and methane escaping from one or more old wells adjacent to the blast site was the likely cause.
What happened in Wheatley could happen in many more communities in southwestern Ontario. To understand the scope of the problem, The Globe and Mail analyzed the oil and gas wells in Ontario and their risks to the public.
Our analysis was based on the Petroleum Well database on Ontario Geohub. This dataset is collected and managed by the Ministry of Natural Resources and Forestry (MNRF) and made accessible to the public through the Ontario Oil, Gas and Salt Resources Library. A total of 26,674 wells were logged in this dataset as of July 2022. More than 640 wells were drilled before 1900, the oldest ones dating back to 1860.
We examined all types of wells in the dataset, not only oil and gas wells but also the wells that support the production of oil and gas such as those used for geological evaluation or testing purposes. We divided wells into four groups based on their status - active (3,532 wells), inactive (858), abandoned (15,257), and unknown (6,210). Nearly 820 wells that could not be located in the field by a petroleum inspector or have been licenced but not drilled yet were excluded from the analysis.
One focus of our analysis was abandoned wells, which no longer produce oil and gas and have been plugged. In Ontario, operators of abandoned wells are required to seal them and return the sites of the wells to their original condition no later than six months from their plugging date.
Abandoned wells account for more than half of the wells in Ontario, and half of them were plugged more than 50 years ago. Cement is used today to plug wells to prevent the migration of oil and gas. But materials used to seal wells can weaken over time and plugging procedures decades ago were not as stringent as today’s standards. As a result, gases can escape and contaminate water sources, harm people’s health and create risks of explosion.
In August 2021 the centre of downtown Wheatley, Ontario, exploded, injuring 20 people, and destroying its downtown core. It was during the third hydrogen sulphide leak in as many months. It never should have exploded. See the full investigation at tgam.ca/WheatleyExplosion
The Globe and Mail
We also examined wells with an unknown status. These either don’t have records at all or their records don’t include details about the status of the well. This may be because the operating company ceased to exist and reporting stopped, or the wells were drilled prior to licencing requirements or proper collection of well information.
Ontario doesn’t have a statutory definition of orphan wells. In other oil-and-gas-producing provinces, such as Alberta, British Columbia and Saskatchewan, orphan wells are those that lack a fiscally viable owner due to insolvency. The responsibility for the wells are transferred to regulators or organizations delegated by regulators.
The Globe identified 7,424 wells that are potentially orphan wells in Ontario, including 1,867 wells that don’t have records of their operators and 4,921 wells that still have an operator listed in the database but their well status is unknown, which means the operator likely no longer exists. Our research found 636 wells for which their owners were found to have filed for insolvency.
When it comes to the risk level of a well, many factors can be taken into account. The Globe examined the distance of a well to the surrounding structures to determine if a well is too close to businesses, homes and public buildings such as schools.
We used OpenStreetMap, an open database of crowdsourced global geodata operated by a non-profit organization registered in England and Wales, to get the locations and shapes of buildings in southwestern Ontario. In Ontario, 75 metres is the minimum distance allowed between a building and an oil and gas well, also called the “setback distance.” The minimum setback distance in Alberta and British Columbia is 100 metres. In Saskatchewan, it’s 125 metres. (The OpenStreetMap building database may contain some types of structures that are not subject to Ontario’s regulations of setback distance, but there is no way to further clean up the data due to a lack of details of the structures.)
With the information on the structures and setback distances, we are able to find wells that are too close to a structure under the regulations of Ontario. We also expanded the analysis to include the greater setback distance in Alberta and B.C. The accuracy of the locations of the wells in the Petroleum Well database also varies - the coordinate of a well is within a radius that varies from 1 metre to 1,000 metres. Our setback-distance analysis zoomed in to southwestern Ontario and only included wells with a location precision higher than 50 metres. We found a total of 1,319 wells located less than 75 metres of a structure, and 1,781 wells less than 100 metres. Nearly 80 per cent of these 1,319 wells are concentrated in the Regional Municipality of Niagara, Norfolk County, and Haldimand County.
Abandoned wells
ONT.
QUE.
Georgian
Bay
Detail
Lake Huron
U.S.
ONTARIO
Toronto
L. Ontario
Kitchener
Hamilton
MICH.
London
Buffalo
Detroit
NEW YORK
Lake Erie
Wheatley
OHIO
PENNSYLVANIA
Wells within 75 metres of a structure
ONT.
QUE.
Georgian
Bay
Detail
U.S.
Lake Huron
ONTARIO
Toronto
Kitchener
L. Ontario
Hamilton
MICH.
London
Buffalo
Detroit
Lake Erie
NEW YORK
Wheatley
OHIO
PENNSYLVANIA
Only wells with location information and accuracy higher
than 50 metres are included.
chen wang and john sopinski/the globe and mail,
Source:Ministry of Natural Resources and Forestry
Abandoned wells
ONT.
QUE.
Georgian
Bay
Detail
Lake Huron
U.S.
ONTARIO
Toronto
L. Ontario
Kitchener
Hamilton
MICH.
London
Buffalo
Detroit
NEW YORK
Lake Erie
Wheatley
OHIO
PENNSYLVANIA
Wells within 75 metres of a structure
ONT.
QUE.
Georgian
Bay
Detail
U.S.
Lake Huron
ONTARIO
Toronto
Kitchener
L. Ontario
Hamilton
MICH.
London
Buffalo
Detroit
Lake Erie
NEW YORK
Wheatley
OHIO
PENNSYLVANIA
Only wells with location information and accuracy higher
than 50 metres are included.
chen wang and john sopinski/the globe and mail,
Source:Ministry of Natural Resources and Forestry
Abandoned wells
Wells within 75 metres of a structure
ONT.
QUE.
ONT.
QUE.
Georgian
Bay
Georgian
Bay
Detail
Detail
U.S.
Lake Huron
Lake Huron
U.S.
ONTARIO
ONTARIO
Toronto
Toronto
Kitchener
L. Ontario
L. Ontario
Kitchener
Hamilton
Hamilton
MICH.
MICH.
London
London
Buffalo
Buffalo
Detroit
Detroit
Lake Erie
NEW YORK
NEW YORK
Lake Erie
Wheatley
Wheatley
OHIO
PENNSYLVANIA
OHIO
PENNSYLVANIA
Only wells with location information and accuracy higher than 50 metres are included.
chen wang and john sopinski/the globe and mail, Source:Ministry of Natural Resources and Forestry
If you have information to help inform The Globe’s reporting on abandoned wells, please e-mail tips@globeandmail.com