At issue are hydraulic fracturing fluids that the industry injects deep into wells. Dick Cheney's infamous 2005 Energy Policy Act exempted so-called "fracking juices" from the federal Safe Drinking Water Act, the law protecting water supplies.

It's known as the "Halliburton Loophole," after the fracking giant that Cheney, a former vice president, once headed.

U.S. Rep. Diana DeGette is pushing to lift the exemption and force companies to disclose the chemicals they use. "Our bill simply closes an unconscionable Bush-Cheney loophole by requiring the oil-and-gas industry to follow the same rules as everyone else," says the Denver Democrat.

Oil and water don't mix, so lose loophole from the Denver Post, Tue Jun 9, 2009 .

Fracking is a big issue in Colorado, and affected well users are getting pretty upset. Here are the articles over the last two weeks.

Fracking not only introduces possibly toxic chemicals into the ground water system, it can radically change the hydrodynamics of the aquafer. Check this video from MSNBC.

As for the seismic activity, either withdrawing fluids or over-pressurizing an oil or natrual gas reservoir will result in light to moderate seismic activity.

The Rangely Field in northwestern Colorado has long been an area of various fracking techniques (including nuclear bombs!) and often sees quakes in the 2-3 zone. The same is true of the area around Trinidad on the New Mexico border.

Over pressuring causes larger quakes if there is a fault system with some stress on it. Pressurized fluids in fault zones don't lubricate the fault, they reduce the amount of stress needed to rupture the fault. This was discovered during the 1960's when fluids (nerve gas, basically) from the Rocky Mountain Arsenal were being pumped down deep wells for disposal. The biggest resulting quake had a magnitude of ~ 6 and was felt throughout the Denver Area.