Imagine you're a Colorado rancher. Times are tough; one day, a company approaches you about leasing a piece of your land, far from your house, for natural gas drilling. The company offers you fair compensation, royalties for any gas recovered, and many assurances that the impact on your land will be minimal. You agree to sign.
This scene, which has replayed many times in the last 15 years all over the country, is becoming more and more common. In some cases, it works out fine. In others, things go drastically wrong.
Hydraulic fracturing -- also known as "fracking" -- is a way of extracting natural gas locked in rock formations up to 10,000 feet below the surface. Companies drill down, and then horizontally, sometimes reaching pockets more than a mile away from the initial site. Then millions of gallons of fracking fluid -- a mix of water, sand, and chemicals -- is forced into the ground, literally fracturing the rock to release natural gas.
Fracking has some benefits: lease payments to landowners, a domestic form of energy, and the fact that natural gas, when burned, emits less greenhouse gas than coal. But is it safe? Drilling companies maintain that fracking takes place too far below groundwater supplies to pose a threat to drinking water. However, in communities around the country where fracking is taking place, nearby drinking water wells have been contaminated with toxic chemicals that may be present in fracking fluid, and with dangerous levels of methane (a highly flammable component of natural gas that can bubble through aquifers).
Drilling companies have largely refused to disclose what they are pumping into the ground -- and the 2005 federal energy bill exempts fracking from the Safe Drinking Water Act's normal regulation of injection wells. However, many proprietary fracking fluid mixes contain chemicals, such as hydrochloric acid and ethylene glycol, that are harmful to human health and the environment.