This morning I read an article in Reader's Digest about abandoned oil wells and air pollution. I'd have guessed they could be in the hundreds, but, they are in the tens of thousands. Oil companies are not the most responsible people and some just abandoned the well site or went out of business.
The wells are spewing methane into the atmosphere and it contributes to global warming as well as other pollutants. .
The cost to cop a well is in the $75.000 range, often much more.