

Imagine a siege of hydrocarbons spewing from deep below ground, polluting water and air, sickening animals and threatening the health of unsuspecting Americans. And no one knows how long it will last.

No, we’re not talking about BP’s gulf oil spill. We’re talking about hydraulic fracturing of natural gas deposits. And if that phrase makes your eyes glaze over, start blinking them open. Fracking, as the practice is also known, may be coming to a drinking well or a water system near you. It involves blasting water, sand and chemicals, many of them toxic, into underground rock to extract oil or gas.

"Gasland," a compelling documentary on HBO airing Monday, June 21 ( 9 p.m. ET/PT), traces hydraulic fracturing across 34 states from California to Louisiana to Pennsylvania. The exposé by filmmaker Josh Fox, alternately chilling and darkly humorous, won the 2010 Sundance Film Festival’s special jury prize for documentary.

It details how former Vice President Dick Cheney, in partnership with the energy industry and drilling companies such as his former employer, Halliburton Corp., successfully pressured Congress in 2005 to exempt fracking from the Safe Drinking Water Act, the Clean Air Act and other environmental laws.

And it highlights the battle in Congress today over whether to repeal the provision that allows gas companies to conceal which chemicals they inject into the ground as "trade secrets." Each well requires the high-pressure injection of a cocktail of nearly 600 chemicals, including known carcinogens and neurotoxins, diluted in 1 million to 7 million gallons of water.

Some 450,000 wells have been drilled nationwide.

Coincidentally, a month before the blowout of the gulf oil well, Energy and Environment Daily, an independent publication, published a draft of proposed language to exempt fracking from chemical disclosure rules in pending Senate energy and climate legislation. The primary author? BP America Inc.