POISONED WATER?: Louis Meeks's well water contains methane gas, hydrocarbons, lead and copper, according to the EPA's test results. When he drilled a new water well, it also showed contaminants. The drilling company Encana is supplying Meeks with drinking water.
© Abrahm Lustgarten/ProPublica

Federal environment officials investigating drinking water contamination near the ranching town of Pavillion, Wyo., have found that at least three water wells contain a chemical used in the natural gas drilling process of hydraulic fracturing. Scientists also found traces of other contaminants, including oil, gas or metals, in 11 of 39 wells tested there since March.

The study, which is being conducted under the Environmental Protection Agency’s Superfund program, is the first time the EPA has undertaken its own water analysis in response to complaints of contamination in drilling areas, and it could be pivotal in the national debate over the role of natural gas in America’s energy policy.

Abundant gas reserves are being aggressively developed in 31 states, including New York and Pennsylvania. Congress is mulling a bill that aims to protect those water resources from hydraulic fracturing, the process in which fluids and sand are injected under high pressure to break up rock and release gas. But the industry says environmental regulation is unnecessary because it is impossible for fracturing fluids to reach underground water supplies and no such case has ever been proven.

Scientists in Wyoming will continue testing this fall to determine the level of chemicals in the water and exactly where they came from. If they find that the contamination did result from drilling, the placid plains arching up to the Wind River Range would become the first site where fracturing fluids have been scientifically linked to groundwater contamination.

In interviews with ProPublica and at a public meeting this month in Pavillion’s community hall, officials spoke cautiously about their preliminary findings. They were careful to say they’re investigating a broad array of sources for the contamination, including agricultural activity. They said the contaminant causing the most concern – a compound called 2-butoxyethanol, known as 2-BE  – can be found in some common household cleaners, not just in fracturing fluids.  

But those same EPA officials also said they had found no pesticides – a signature of agricultural contamination – and no indication that any industry or activity besides drilling could be to blame. Other than farming, there is no industry in the immediate area.

In Pavillion, a town of about 160 people in the heart of the Wind River Indian Reservation, the gas wells are crowded close together in an ecologically vivid area packed with large wetlands and home to 10 threatened or endangered species. Beneath the ground, according to the U.S. Geological Survey, the earth is a complex system of folded crusts containing at least 30 water-bearing aquifer layers.

EPA officials told residents that some of the substances found in their water may have been poured down a sink drain. But according to EPA investigation documents, most of the water wells were flushed three times before they were tested in order to rid them of anything that wasn’t flowing through the aquifer itself. That means the contaminants found in Pavillion would have had to work their way from a sink not only into the well but deep into the aquifer at significant concentrations in order to be detected. An independent drinking water expert with decades of experience in central Wyoming, Doyle Ward, dismissed such an explanations as "less than a one in a million" chance.