The hunt for the natural gas fields that could help make the U.S. more energy independent has brought developers to the edge of the watershed for one of the world''s biggest cities, as reported by the Associated Press. Now drilling in the Marcellus shale formation, which some estimate could meet the nation''s natural gas needs for the next decade, has raised fears of tainted drinking water in New York City. To extract the gas, well operators blast millions of gallons of water treated with chemicals into horizontal cracks a mile under the earth, a process commonly known as fracking. A well is bored thousands of feet beneath potable water supplies before branching out horizontally. Fracking fluid is blasted into the shale, opening cracks several hundred feet wide that let trapped gas escape. Some of the fracking fluid, which is comprised of about 99 percent water and less than 1 percent of various chemicals, stays in the ground after drilling. New York is one of only five U.S. cities that has been granted a waiver on federal requirements to filter tap water. At a recent city council environmental protection committee meeting, councilmen argued that fracking could force the city to spend billions on a filtration plant, negating any financial gains from drilling. The city operates six reservoirs in the Catskill region of upstate New York that are fed by rainwater, mountain runoff and streams. The reservoirs deliver 1.2 billion gallons of water each day to more than 8 million people. The city is under severe financial strain and could, turn a huge profit selling mineral rights. The chair of the committee rejects that possibility outright. In the meantime, developers are lining up for a piece of the Marcellus shale. Producers say drilling is safe. There are 835 active drilling applications in the state, a 28 percent increase since 2007. None of the permits allow for drilling in the watershed, according to the New York DEP.