Boom in gas drilling fuels contamination concerns in Colorado
COMMENT: 'Fraccing" - fracturing the host substrate in which natural gas is contained - is of increasing concern in British Columbia. It is a common practice with conventional natural gas production, but will escalate phenomenally with the wholesale move to BC's shale gas prospects. Shale doesn't give up its gas readily, and wells require almost continuous fraccing to produce efficiently. Similarly, fraccing of coal to produce coalbed methane is standard industry practice.
As with Colorado, there is very little disclosure in BC of what goes into fraccing "muds" and no regulation, that I am aware of, that restricts fraccing, requires baseline and operational testing and monitoring, or requires disclosure of what substances are being injected into the ground. This article says that benzene, glycol-ethers, toluene, 2-(2-methoxyethoxy) ethanol, and nonylphenols are used in fraccing fluids. In 2004, EnCana was fined in Colorado when toxic fluids it was using seeped into groundwater. EnCana is the leading shale rights owner in BC.
By Josh McDaniel
Some scientists and citizens want firms that extract natural gas to reveal what chemicals they’re using.
Grand Junction, Colo.
When Lisa Bracken noticed gas bubbling to the surface of Divide Creek, which runs along one side of her 60 acres in western Colorado, she suspected another gas “seep.” It had happened once before, in 2004, after faulty natural-gas drilling in the vicinity contaminated the creek with benzene and methane.
Her concern, though, is not confined to the small waterway. Her cottonwood and pinyon trees are dying, along with parts of meadowland that her family manages for wildlife, and Ms. Bracken believes the likely culprit is methane seepage stemming from one or more of the 11 natural-gas wells within a mile of her property – though independent investigations have not been able to prove a link.
“It is so frustrating to watch the land die,” she says. Bracken does not think the current drought is responsible. “We have seen it go through drought cycles, but nothing like this. The land has lost its ability to sustain itself.”
Her concern and that of others is putting new scrutiny on a drilling practice knows as “fracing,” short for hydraulic fracturing.
A common component of natural-gas extraction worldwide, fracturing operations inject water, sand, and a cocktail of chemicals at high pressure into rock formations thousands of feet below the surface, opening existing fractures in the rock and allowing gas to rise through the wells. The practice makes drilling possible in areas that 10 to 20 years ago would not have been profitable, including parts of Colorado, which accounts for 6.2 percent of natural-gas produced in the US.
The concerns center mainly around the injected fluid. Most comes back to the surface, but 30 to 40 percent is never recovered, according to industry estimates.
The composition of hydraulic fracturing fluids is proprietary, and energy companies are vehement about the need to keep the contents secret to protect their competitive edge. That confidentiality is protected by the federal Energy Policy Act of 2005, which exempted hydraulic fracturing from regulation under the Safe Drinking Water Act.
“We now use five to 10 ‘frac’ jobs per well, with up to 100 million gallons of fluid used per frac,” says geologist Geoffrey Thyne of the University of Wyoming, whose analysis of the large gas fields around Divide Creek found elevated methane and chloride levels in groundwater samples.
“They are injecting fluid that may or may not be hazardous into thousands of wells and not recovering all of it. We have to ask, what is in those fluids and where does the fluid go?” says Mr. Thyne.
Theo Colborn, a leading researcher on the effects of toxins on the human endocrine system, has been trying to glean what is in the injection fluid.
Preliminary results of her study identify 65 chemicals that are probable components. She is urging that groundwater sampling be expanded to determine whether these chemicals or their byproducts are showing up in areas where hydraulic fracturing is being used.
“We know less and less about what chemicals are being used, but the ones that we do know are being used are very dangerous,” says Dr. Colborn.
Chemicals such as benzene, glycol-ethers, toluene, 2-(2-methoxyethoxy) ethanol, and nonylphenols were used in the fracturing fluids, her study found – all of which have been linked in previous research to health disorders when human exposure is too high.
Pushing for legislation
Colborn’s work and complaints from residents living near drilling operations are spurring policymakers to take a closer look at hydraulic fracturing. US Reps. Diana DeGette (D) and John Salazar (D), both of Colorado, have introduced legislation that would repeal the Safe Drinking Water Act exemption for hydraulic fracturing and force energy companies to reveal the contents of the fracturing fluids.
“There is little reason to continue the exemption,” says Representative DeGette in a phone interview. “Communities have a right to know what is potentially threatening their water.”
Energy industry officials say there’s no evidence that hydraulic fracturing contaminates groundwater or threatens public health.
“This is an answer in search of a problem,” says Doug Hock, a spokesman for EnCana, the firm that is drilling near Bracken’s land. “Chemicals in themselves do not create risk; risk is created when the proper technology and procedures are not in place. We take very stringent precautions.”
Colorado fined EnCana $371,000 – the largest fine in state history for a drilling-related incident – after finding the company responsible for the 2004 gas seep in Divide Creek. But the state is allowing drilling to continue in the area.
The proposed federal legislation would only increase the regulatory burden on industry but do little to protect human health, suggests Dollis Wright, a public-health consultant who has conducted studies for the Colorado Oil and Gas Association. “There are groups out there that are listing chemicals found in the fluids, and they always say such and such chemical causes cancer.
Well, just because a chemical is in the fluids does not mean it is going to get into your water. And if it gets into your water, it does not mean that it is going to cause harm,” she says. “It may have to be inhaled, rather than drunk, to cause the negative effects they cite.”
Others argue the legislation is well past due. “If you don’t know what you are looking for, it is hard to do analysis,” says Susan Griffin, a toxicologist with the US Environmental Protection Agency in a phone interview. “There are a lot of good scientific tools out there, but we need opportunities to apply them. Those opportunities don’t exist right now.”
‘Fracing’ to blame for explosion?
Ben Bounds, for one, would like additional assurances about fracing’s safety.
In the summer of 2007, methane seeped from his domestic well and exploded inside his pump house. The explosion lifted the pump-house roof off the frame and melted or singed everything inside. A few days later, a state inspector with a methane detector investigated the Bounds property in rural Huerfano County, at the base of the Sangre de Cristo Mountains.
“When he opened the door to the garage, the detector went absolutely crazy,” says Mr. Bounds.
While 50 methane drilling wells and active hydraulic fracturing operations are nearby, a lack of independent monitoring and testing has made it impossible to prove that fracing created pathways for methane to collect in Bounds’s domestic water system.
Bounds and his family immediately evacuated the home, and they’ve had to evacuate many times since when detectors Bounds installed have signaled the presence of methane.
The state advised that Bounds not allow his grandchildren or any visitors to come to the property, and his insurance company has threatened to drop coverage. He has thought about simply abandoning the home since he could not in good conscience sell the property.
“Why are they allowed to keep this a secret? That’s not right,” Bounds says. “It only seems like common sense to me that they would have to release the contents of those fluids and prove they aren’t causing problems.”Posted by Arthur Caldicott on 07 Feb 2009