In Texas and across the country, controversy is escalating over the practice of "fracking," which involves shooting water, sand and chemicals far underground to retrieve natural gas. So some companies have responded by using less-dangerous chemicals, and fewer of them.
Formally called hydraulic fracturing, the drilling practice has been suspected of contaminating the groundwater of some nearby homeowners. Range Resources, a Fort Worth-based drilling company, has "eliminated a number of the additives we've had in the past," says Matt Pitzarella, its public affairs director. In addition, he says, this year the company began using a "100 percent biodegradable friction reducer" in drilling operations and has also begun using other more environmentally benign chemicals. Many of Range's improvements apply to Pennsylvania, where it drills most, but the company plans to bring such practices to wells near Fort Worth.
Halliburton is testing ultraviolet light as a means of eliminating bacteria from drilling fluid, according to Bloomberg News, as opposed to a chemical biocide. Bacteria pose a risk because they can grow in the hot fluid and damage the pipes and reduce the flow of gas. Multi-Chem, which makes chemicals for gas wells for companies including Range Resources, also is working on "low toxicity" chemicals as part of its "NaturaLine" products. Some are already in use; others are being developed.
The effect of industry efforts remains uncertain. Companies use a variety of chemicals in hydraulic fracturing, which involves breaking up rock formations to free the gas. Company claims like "low toxicity" or "biodegradable" are difficult to evaluate. Also, companies closely guard the recipes for their chemical concoctions at the wellheads, claiming they are proprietary. Patricia DeMarco, who follows fracking issues as executive director of the Pennsylvania-based Rachel Carson Homestead Foundation, says she had not yet seen results of any research into such non-toxic chemicals.
Nonetheless, any steps toward limiting contamination may be welcome news to residents of Fort Worth, one of several national hubs for hydraulic fracturing. The city sits above a vast deposit known as the Barnett Shale, and many people with wells near their homes fear the potential impact on their water supply. A recent movie called Gasland, about fracking practices nationally, showed some homeowners lighting their gas-contaminated tap water on fire. Last week 1,000 people turned out in Pennsylvania at an Environmental Protection Agency meeting on fracking, and earlier this month, more than 600 people flocked to a similar EPA meeting in Fort Worth. Calvin Tillman, the outgoing mayor of Dish, told of a local family whose well had tested positive for arsenic, lead and other chemicals.
The industry maintains that many fracking chemicals, like ethylene glycol and guar gum, are found in ordinary household products. But the U.S. House Energy and Commerce Committee, which is probing the practice, also received acknowledgement from some drilling companies that their fluids contain benzene, toluene, ethylbenzene and xylenes — which, according to the committee, "could pose environmental and human health risks." But the industry also argues that the chemicals are highly diluted, because the fracking concoction is generally 99 percent sand and water. Indeed, the process requires a vast amount of water: 2 million to 5 million gallons of water per well, according to the EPA.
The industry arguments have some merit, according to Danny Reible, who holds an environmental health engineering chair at the University of Texas and has served on a committee that advises the EPA study on hydraulic fracturing. Most fracking-fluid ingredients aren't that toxic, he says. But, he adds, the water flowing back out of the natural-gas wells can pick up oily sediments. Anywhere between 25 and 80 percent of water flows back out of the wells, depending on the geologic formation, according to a representative of the industry website Energy in Depth.
"If you're not handling it right at the surface or near the surface, that's an issue as well," Reible says.
Drilling and chemical companies acknowledge that the recent wave of environmental agitation over fracking has made an impact. The push "has led to increased focus on alternative chemistries," says Cade Bourque, the health, safety and environment director at Multi-Chem. Borque says his company also uses an environmental evaluation system, with the help of the Britain-based Center for Environment, Fisheries & Aquatic Science, to help companies chose safer chemicals.
Pitzarella, of Range Resources, notes that some environmentally friendly practices carry an economic payoff: The chemicals often are expensive, so using them less saves money.
Environmentalists remain skeptical of industry safety efforts. DeMarco, of the Rachel Carson Homestead Foundation, points out that few outside the companies know what chemicals go into fracking projects in the first place, due to a special exemption that the gas industry obtained in 2005 from the Safe Drinking Water Act. "Many of these companies are also claiming that their fracking cocktail is a proprietary and privileged piece of information," she says. Range Resources, however, made a splash earlier this month by announcing that it would publish a list of its fracking chemicals — wellhead by wellhead — in Pennsylvania. The company has not announced plans to do so in the Barnett Shale.
DeMarco also pointed out that the enormous volume of water required for fracking meant that the absolute amount of the chemical, rather than the ratio, was important. "Even if it's only 1 percent, it's still a lot of stuff in absolute numbers," she says. In the Barnett Shale, Oklahoma City-based Devon Energy has earned praise for recycling some of the water used in fracking.
Meanwhile, the major EPA study of fracking will get under way soon and should answer some of these questions. But for some irate drilling-area residents, the EPA study can't come soon enough: At the Pennsylvania meeting last week, one speaker said that the EPA was effectively studying the flammability of Rome while it is burning.