he experiment first touched the lives of Laura and Larry Amos in 1998, when a Montana-based company called Ballard Petroleum sent one of its landmen to call. He politely explained that Ballard had leased the rights to the gas under their land, and that the company was ready to break ground on the first set of wells in the neighborhood. The Amoses could either accept a check for $3,000, he said, or refuse the payment -- and watch the development move forward anyway.
The company agreed to build the concrete pad for the wells out of sight of the Amos house, and the Amoses learned to live with the disruption. But Ballard returned in 2000, this time with plans to drill on the property next door. Like the Amoses, the neighbor asked that the well pad be built as far from his home as possible. That placed it in full view of the Amoses' front porch -- less than 250 yards from their kitchen sink.
On May 1, 2001, while Laura, Larry, and their 6-month-old daughter, Lauren, were visiting Laura's parents in Kansas, Ballard and its contractor, BJ Services, fractured three wells on the pad neighboring the Amos property. That same day, a family employee called the Amoses to report that the metal cap on their water well had blown into the air, flooding the surrounding pasture with a fountain of murky, fizzing water.
The geyser subsided, but the Amoses' tap water remained filled with dark gray sediment and bubbled as busily as soda pop. The Colorado Oil and Gas Conservation Commission, the agency that oversees oil and gas development in the state, sent a representative to inspect the damage, and tests showed that the well water was contaminated with methane gas. Though methane is believed to be nontoxic in drinking water, it poses other threats: At the concentration detected in the Amos well, the state warned, gas entering through the faucets could collect inside the house and explode. (The state advised the family to keep closets and crawl spaces ventilated).
The Amoses immediately blamed hydraulic fracturing for their troubles, but the oil and gas commission, and Ballard, argued that the fracturing had taken place more than a mile underground, far below the 225-foot-deep well. They also pointed out that instrument readings taken during the fracturing jobs showed no sign of a problem.
Yet Geoffrey Thyne, a geologist at the Colorado School of Mines in Golden, who has studied the incident as a consultant to Garfield County, concluded that the deep fracturing was at least an indirect cause of the backyard geyser. "Water wells just don't do that," he says, "unless you apply pressure to the bottom." Thyne surmises that the pressurized fracturing fluids shoved gas or liquid through a much shallower leak in the side of one of the gas wells. That gas, he says, could then have found one of the natural underground fissures abundant in the area and moved through it into the Amos well.
Some two weeks after the well burst open, Ballard started delivering water to the Amos household, and the family began using that water for drinking and bathing. They occasionally had problems with the outdoor tank that held the water, and when disruptions occurred they often turned back to their own well water. It wouldn't hurt, the Amoses thought, to bathe their daughter in the water every once in a while, or even use it to make a cup of coffee when the sediment wasn't too thick.
In late August 2001, the state again tested the Amos well water and found only traces of methane gas. The levels were so low that further tests to pinpoint the source of the gas were impossible. Given this lack of evidence, the state decided, Ballard could not be held responsible for the contamination. Garfield County rock contains a lot of gas, and there was a chance that the methane in the Amos well had come from another source. By October, after about four months of service, Ballard had stopped delivering water to the Amos home. Yet water from the family well, Laura Amos says, remained foul-smelling and murky.