The Environmental Protection Agency's science advisors meet today to begin studying the impacts on drinking water of the gas drilling practice known as hydraulic fracturing.
While the gas industry argues that the chemical-infused technique is perfectly safe and vital to reaching vast gas supplies, concerns about its potential impact on water supplies is spreading outward from New York, where an environmental review process has held up gas drilling in parts of the Marcellus Shale, a gas-rich formation that underlies several states including Pennsylvania, Ohio and West Virginia.
The city of Philadelphia is also now attempting to block gas drilling near the Delaware River watershed, which supplies about half of the city's tap water. The City Council unanimously passed a resolution in late March that calls on the Delaware River Basin Commission to deny any hydraulic fracturing permits.
Hydraulic fracturing, or fracking, involves injecting large quantities of water along with secret mixes of chemicals deep underground in order to break up gas-containing rock formations. The technique has been used for decades, but in the Marcellus Shale region, it is combined with horizontal drilling and other methods that environmentalists fear could pollute groundwater sources and cause severe problems downstream.
"The EPA study is a really great start to answer some questions," said Erika Staaf, clean water advocate for the non-profit PennEnvironment. "If drilling is moving forward, which it is, we want to make sure that it happens in a way that fully protects the environment, aquatic life, habitats, our forests and public health."
Fracking is already under way in parts of Pennsylvania, and oil and gas companies such as Exxon and BP are lobbying Congress to keep all potential obstacles — including regulators — out of the way. The Marcellus Shale holds about 350 trillion cubic feet of natural gas — enough to keep the country going for 15 years at present consumption rates.
"Ideally, what they would be doing is either slowing down the drilling or stopping the drilling until they have a better sense of what the science is," said Deborah Goldberg, a managing attorney with Earthjustice's Northeast office.
"There have been no signs of that happening in Pennsylvania, and in New York, it's happening only because of the environmental review process, and when that's over, we expect there will be huge pressure to drill."
So far, most of the documented connections between fracking fluid and drinking water involve individual wells. In Western Pennsylvania, however, there is some indication of larger dangers.
During drought conditions in the summer of 2008, a drinking water advisory was issued covering about 350,000 people in the Pittsburgh area citing high levels of "total dissolved solids," or TDS, in tap water coming from the Monongahela River. TDS can cover a number of substances, including salts and some potentially more dangerous chemicals.
The Pennsylvania Department of Environmental Protection listed a number of potential sources — including increases in "non-conventional drilling." The DEP instructed sewage treatment facilities that had been accepting wastewater from fracking wells to reduce the amount they treated, from 20 percent of the total down to 1 percent.
Elsewhere, fracking projects in Wyoming have apparently resulted in contamination of some drinking water wells, although officials said the presence of chemicals like 2-butoxyethanol could come sources other than gas drilling. Pittsburgh's TDS levels remain the only documented case of a large water supply with contamination potentially associated with hydraulic fracturing.
Drilling companies generally keep the contents of their "fracking fluid" private, but mixtures of chemicals including benzene and other carcinogens have been used. Wastewater from wells can contain traces of those chemicals as well as naturally occurring substances that are pulled up from deep underground; these tend to include salts, and wastewater has been found to be as much as five times as salty as seawater.
Will Study Lead to Regulation?
Goldberg said it is unlikely that the EPA will step in and strictly regulate fracking in the Marcellus Shale area, in spite of the study starting now.
"To do a really serious study of the impacts on drinking water is a monumental undertaking, because it really requires some very serious hydrological studies that either are not being done or are being done only by industry and are not being shared," she said, adding that if drilling near the Delaware River's headwaters does move forward, drinking water could be at risk in New York and Philadelphia.
"I think that the likelihood of their protection increases with the vigilance of the citizens who care about this," she said. "I think the people in New York, the people in Pennsylvania, need to take the responsibility to ensure that their governments are stepping to the plate and protecting their water supply even while this is going on."
Such action seems to have worked, at least for the moment, in the Philadelphia area. The non-profit group Delaware Riverkeeper Network was among many to applaud the City Council's move to block hydraulic fracturing permits. Deputy Director Tracy Carluccio said, "We're putting their feet to the fire in our watershed, and that's one of the reasons there are no wells yet. It has been held up even though the rest of Pennsylvania is going like gangbusters."
For its part, the oil and gas industry maintains that fracking is a proven process with a long track record of environmental safety. An industry group called the Marcellus Shale Coalition, which is made up of dozens of companies, said it will participate and aid in the EPA's study "as appropriate." Generally, the industry claims that fracking is already appropriately regulated by states, even though those regulations vary drastically around the country.
There are currently twin bills, dubbed the FRAC Act, in both houses of Congress that would bring regulation of fracking under some federal oversight. The legislation would give EPA authority to regulate fracking, and it would also require that companies disclose specifically what chemicals are in the fracking fluids used. A Bush administration decision in 2005 exempted fracking from regulation under the Clean Water Act, and since then industry has been slow to reveal the chemical concoctions used in the wells.
"There have been no identified groundwater contamination incidents due to hydraulic fracturing, as noted by the Pennsylvania Department of Environmental Protection, other state regulators and the U.S. Groundwater Protection Council," the coalition said in a statement. "Our industry is confident that an objective evaluation of hydraulic fracturing will reach the same conclusion as other studies – that it is a safe and well-regulated process that is essential to the development of natural gas."
Environmentalists disagree, but it is unlikely the EPA will come to any conclusion on the issue until 2012. And even if threats to drinking water don't move regulators to act against the practice, Goldberg noted a number of other environmental impacts fracking can have as well.
"It's really only a part of the problem," she said. "The transmission pipelines are known to have a lot of leakage of methane, which is a very potent greenhouse gas. There are huge amounts of diesel fuel used for both the trucks and drilling rigs, and the emissions from those combine with sunlight and tend to create big ozone problems in areas where you would never expect to see it. From a health perspective, the air problems are probably even more important than the water problems."