The stories you want. The opinions that matter.
No, thanks
Tag: drinking water
Natural Gas Contaminated Drinking Water In Texas, Study Says

Natural Gas Contaminated Drinking Water In Texas, Study Says

By Neela Banerjee, Tribune Washington Bureau

WASHINGTON — Natural gas production near homes in a Texas subdivision contaminated residents’ well water, according to a study published Monday. The discovery was made in a community where the Environmental Protection Agency halted its own investigation two years ago.

In the course of a broader effort to determine the origins of high methane levels in drinking water aquifers near gas wells in Pennsylvania and Texas, scientists found that water in two homes in Parker County, Texas, changed over nine months from containing trace amounts of methane to having high levels.

The newly identified cases “caught this contamination in the act,” said Robert Jackson, a study co-author and professor of environmental science at Stanford University.

The discovery poses a challenge to a long-standing assertion by the oil and gas industry that the energy boom sweeping the country has not damaged water supplies. Other studies have found that water wells near natural gas production are at greater risk of containing methane than those farther away. But industry has contended that the methane found in water wells is naturally occurring and was there all along, prior to the start of gas production.

Each of 20 homes tested in Parker County has detectable methane in its well water because of many layers of oil and gas in the ground, the researchers said. Methane that enters homes through drinking water poses an explosion risk if it accumulates in rooms or spaces.

The two homes whose water had negligible amounts of methane in 2012 were tested again in August and November 2013, when they showed far higher levels, the study said. Further, the methane in the homeowners’ water no longer had the chemical makeup of the naturally occurring trace gas, according to the study. Instead, it had the same chemical fingerprint as natural gas deposits far below the aquifers, the scientists found.

“All the gas chemistry in the water changed so that it wasn’t just higher methane levels but higher methane from a totally different source,” said Thomas Darrah, assistant professor of earth sciences at Ohio State University and the study’s lead author.

Darrah and his colleagues concluded that the water contamination occurred when natural gas from a lower geological depth migrated higher into drinking water sources because of a faulty cement job around the well.

The researchers believe that in nearly all the cases, the water contamination occurred because poor casing or cementing around the gas wells allowed methane to leak out the sides and into aquifers. Said Darrah, “The good news is that most of the issues we have identified can potentially be avoided by future improvements in well integrity.”

The findings of the study, published in the Proceedings of the National Academy of Sciences, spotlight the EPA’s controversial decision in 2012 to halt its investigation into possible well-water contamination in Parker County by the energy company Range Resources.

The EPA got involved in 2010 because Range Resources and Texas regulators failed to act immediately on homeowners’ complaints of possible drinking water contamination, according to a 2013 report by the EPA inspector general. When the EPA conducted its own tests of well water in some Parker County homes, it found such high levels of methane in the water supply of two homes that it posed a risk of explosion, the report said.

The Justice Department filed a complaint on behalf of the EPA against Range in January 2011 but withdrew it by March 2012. The EPA and Justice Department reversed course because the EPA worried about the costs and legal risks of the case, the inspector general’s report said. Texas authorities and Range deny that the company’s gas development had contaminated the residents’ water.

The two Parker County homes that showed new contamination are near wells drilled by Range in 2009 and sold in 2011 to Legend Natural Gas.

The new contamination was identified as part of a wider study that tested drinking water in 20 wells in the Barnett Shale in Texas and 113 wells in Pennsylvania’s Marcellus Shale area.

In Texas, extremely high levels of methane were found in five homes, including the two whose contamination the researchers captured through their testing. In Pennsylvania, high levels of methane were found in 20 homes.

At least one house in Pennsylvania had high levels of methane that was there all along, unrelated to gas production. But for the other homes in the two states, the chemical fingerprint of the methane at high levels in drinking water was the same as natural gas in deeper formations, the study said. The second line of evidence, the chemical fingerprint of gases found with methane in the Texas and Pennsylvania, also indicated the methane came from lower depths, according to the study.

Photo: danielfoster437 via Flickr

Interested in national news? Sign up for our daily email newsletter!

Oil Companies Fracking Into Drinking Water Sources, New Research Shows

Oil Companies Fracking Into Drinking Water Sources, New Research Shows

By Neela Banerjee, Tribune Washington Bureau

WASHINGTON — Some companies are fracking for oil and gas at far shallower depths than widely believed, sometimes through underground sources of drinking water, according to research released Tuesday by Stanford University scientists.

Though researchers cautioned their study of hydraulic fracturing, or fracking, employed at two Wyoming geological formations showed no direct evidence of water-supply contamination, their work is certain to roil the public health debate over the risks of the controversial oil and gas production process.

Fracking involves high-pressure injection of millions of gallons of water mixed with sand and chemicals to crack geological formations and tap previously unreachable oil and gas reserves.
Fracking fluids contain a host of chemicals, including known carcinogens and neurotoxins.

Fears about possible water contamination and air pollution have fed resistance in communities around the country, threatening to slow the oil and gas boom made possible by fracking.

Fracking into underground drinking water sources is not prohibited by the 2005 Energy Policy Act, which exempted the practice from key provisions of the Safe Drinking Water Act. But the industry has long held that it does not hydraulically fracture into underground sources of drinking water because oil and gas deposits sit far deeper than aquifers.

The study, however, found that energy companies used acid stimulation, a production method, and hydraulic fracturing in the Wind River and Fort Union geological formations that make up the Pavillion gas field and that contain both natural gas and sources of drinking water.

“Thousands of gallons of diesel fuel and millions of gallons of fluids containing numerous inorganic and organic additives were injected directly into these two formations during hundreds of stimulation events,” concluded Dominic DiGiulio and Robert Jackson of Stanford’s School of Earth Sciences in a presentation Tuesday at the American Chemical Society conference in San Francisco.

The scientists cautioned that their research, which is ongoing and has yet to be peer-reviewed, “does not say that drinking water has been contaminated by hydraulic fracturing.”

Rather, they point out that there is no way of knowing the effects of fracking into groundwater resources because regulators have not assessed the scope and impact of the activity.

“The extent and consequences of these activities are poorly documented, hindering assessments of potential resource damage and human exposure,” DiGiulio wrote.

Underground sources of drinking water, or USDWs, are a category of aquifers under the Safe Drinking Water Act that could provide water for human consumption.

“If the water isn’t being used now, it doesn’t mean it can’t be used in the future,” said DiGiulio, a Stanford research associate who recently retired from the Environmental Protection Agency. “That was the intent of identifying underground sources of drinking water: to safeguard them.”

The EPA documented in 2004 that fracking into drinking water sources had occurred when companies extracted natural gas from coal seams. But industry officials have long denied that the current oil and gas boom has resulted in fracking into drinking water sources because the hydrocarbon deposits are located in deeper geological formations.

“Thankfully, the formations where hydraulic fracturing actually is occurring … are isolated from USDWs by multiple layers and often billions of tons of impenetrable rock,” said Steve Everley, a spokesman for Energy in Depth, an industry group.

Industry officials had not seen the Stanford research.

DiGiulio and Jackson plotted the depths of fracked wells, as well as domestic drinking water wells in the Pavillion area. They found that companies used acid stimulation and hydraulic fracturing at depths of the deepest water wells near the Pavillion gas field, at 700 to 750 feet, far shallower than fracking was previously thought to occur in the area.

“It’s true that fracking often occurs miles below the surface,” said Jackson, professor of environment and energy at Stanford. “People don’t realize, though, that it’s sometimes happening less than a thousand feet underground in sources of drinking water.”

Companies say that fracking has never contaminated drinking water. The EPA launched three investigations over the last six years into possible drinking water contamination by oil and gas activity in Dimock, Pa.; Parker County, Texas; and Pavillion, Wyo. After initially finding evidence of contamination at the three sites, the EPA shelved the investigations amid allegations by environmentalists and local residents that the regulator succumbed to political pressure.

Jackson said the Stanford study’s findings underscore the need for better monitoring of fracking at shallower depths. “You can’t test the consequences of an activity if you don’t know how common it is,” he said. “We think that any fracking within a thousand feet of the surface should be more clearly documented and face greater scrutiny.”

Photo: Maryland Sierra Club via Flickr

Interested in national news? Sign up for our daily email newsletter!