How does oil pollute the ground when it comes from the ground?

Question

My mom popped up and asked this, so I figured I would find out.

Answer 1

Correction- petroleum comes from the ground.

"oil" hat powers our cars have been heavily processed and treated chemically, so it naturally will hurt the earth and soil after a while.

Answer 2

It isn't so much that it isn't polluting the earth as it is being where it shouldn't be. For intance, not many people dig that far down into the earth, so letting it sit there as pockets or rivers of oil far under the surface does no harm.

Bringing it to the surface you can have it inviltrate ground water and potable water supplies, springs, city systems etc.

It can smother the surface vegitation and wild life as in the Exxon Valdez disaster. Refined and put into vehicles the oil has additives and detergents which effect ecology if you have people disgarding of oil out in the open or down storm drains or heavy leaks on the ground.