Pump-jacks make way too much pollution

[BlakeMW]

20 depleted pumpjacks will run a single refinery, assuming no modules anywhere. With modest speed module use you can easily raise that to 10 depleted wells to run a single refinery.

How useful this is really depends on how many wells there are. RSO tends to create very few wells with very high amounts so depleted well income tends to be insignificant, but vanilla tends to make lots of small wells so the depleted well income can be quite significant.