Inactive oil and gas wells are leaking methane and other pollutants. An enormous backlog of them has built up in Alberta, Canada alone. It grows about 6 percent each year. There are now 97,920 inactive wells there, more than a quarter leaking. Wells can be thousands of feet deep, with concrete casing and steel piping meant to isolate them from the soil, rock and water they pass through. Over time, all wells can erode, vulnerable to salty water, corrosive gas, earthquakes and other environmental changes. Who knows how many of these leaking inactive wells there are elsewhere?
www.nytimes.com/2020/10/30/climate/oil-wells-leak-canada.html?action=click&module=Well&pgtype=Homepage§ion=Climate%20and%20EnvironmentS.com