By my definition, if subterranean water is “thousands of feet” below the surface, it is not “ground water.”
I can dream up a situation in which any improperly completed oil or gas well pollutes fresh ground water. Fracking has been around at least 50 years.
Obama’s hysteria is driven by politics (as if people on this forum didn’t know that! LOL).
Oldplayer
Water that is 2000 feet below the surface in Wyoming (Elevation 5000 feet) will eventually leach its way into surface water from the exposed rocks in Arizona, Utah or New Mexico (elevation 2000 feet)
Of course it could take thousands of years, but eventually it pops out somewhere.
The water leaching out of some of the rocks at the bottom of Zion National Park is rainwater that fell on the ground around the time of Christ. (At least that's what the Park Rangers said).