Last week, three spills of potentially carcinogenic hazardous chemicals at a natural gas drilling site in Pennsylvania prompted the state's environmental protection agency to suspend Cabot Oil & Gas's operations in the county.
The spills were just a small part of a larger phenomenon — accidents at natural gas drilling sites that have imperiled the drinking water of nearby communities in states from Pennsylvania to Wyoming and that have no governmental oversight.
They call it the "Halliburton Loophole" — an exemption for oil and gas companies to inject hazardous materials directly into or near underground drinking water supplies in a process called hydraulic fracturing.
Hydraulic fracturing, commonly called "fracking," is used in natural gas wells to push fluid and sand at very high pressure into rock formations to release gas. Fracking fluid can contain chemicals that are hazardous and carcinogenic. Halliburton, a pioneer of the technique, says 35,000 wells are fracked each year.
As more accidents are reported at wells being "fracked" (undergoing hydraulic fracturing), both houses of Congress are considering legislation to close the Halliburton Loophole, so nicknamed not just because Halliburton developed the technique but also because former Halliburton CEO and ex-vice president Dick Cheney urged the creation of the exemption in 2005.
More than 160 community and national groups have signed a letter of support for the bills in Congress.
"We think everybody deserves to have their drinking water protected. It's pretty simple," says Amy Mall, senior policy analyst at the Natural Resources Defense Council, who has blogged regularly about fracking accidents.
"There is a federal law that protects groundwater from underground injection" — the Safe Water Drinking Act — "but this one industry has a particular loophole. They should be subjected to the same laws regarding underground pollution."
The problems that have surfaced at these drilling sites show that even the cleanest-burning fossil fuel can pose dangers to human health and welfare during extraction. And just like the coal industry with mountaintop mining, the oil and gas industry has launched a campaign to fight any new legislation that might subject its methods to closer scrutiny.
Often with fracking operations, groundwater supplies are at shallower levels than the natural gas deposits — say, 500 feet down as opposed to 5,000 — requiring companies to drill through aquifers to obtain gas. If an accident occurs underground, the fracking liquids can migrate into drinking water. The pending legislation would require companies to disclose what chemicals are in their fracking fluids.
Tracy Carluccio, deputy director at Delaware RiverKeeper, says Pennsylvania has seen a number of fracking accidents as the number of wells for both oil and gas in the state has increased from 2,000 in 1999 to 4,456 wells just for natural gas alone in 2009 up until September 22.
Many of those wells are found in the Marcellus shale, a vast formation of deep shale, rich in natural gas, stretching from Virginia through West Virginia, Ohio, Pennsylvania and into New York. Geologists have estimated the formation contains anywhere from 50 trillion cubic feet of natural gas to 516 trillion cubic feet — 25 times the country's current annual production, but extracting that gas in a cost-effective way requires extreme methods.
"We're seeing a real ramp-up of activity of wells going in, and accompanying this rush is drilling companies installing their wells as quickly as possible to make it economical for them. The result of this rush to slapdash these things in the ground are that accidents happen," Carluccio says.
In a notorious incident in Dimock, a town in northeastern Pennsylvania, the state believes that methane leaking from a fracking site into a residential well caused an explosion that blew away a several-thousand-pound concrete slab. This type of incident has been repeated at other places across the country, including Bainbridge, Ohio, where gas that accumulated in a basement caused an explosion that lifted an entire house off the ground and blew its doors 20 feet from their hinges.
Such an accident happens like this: A well bore is drilled down into the layer of earth that contains the gas, a space that is usually far below drinking water but under strong pressure. When a drill bore punctures the space, it creates a pressure release point. Companies often use as many as three rings of steel pipe to keep the gas and fracking fluids from leaking out. When the bore goes through areas holding drinking water, concrete should be used to seal the spaces between the pipes. However, if this is not done, or is not done properly, then the fracking liquids and the gas can leak to other areas underground. As in the cases in Bainbridge and Dimock, the gas leaks up until it can't go any further, and the pressure builds or the gas collects until a spark ignites it.
Last month in Wyoming, the EPA confirmed the presence of hydraulic fracturing chemicals in drinking water wells near fracking operations around the town of Pavillion, where residents had complained for years about the water quality — and had been told by the companies that drilling had nothing to do with the problem. In New York, where the Marcellus shale underlies part of the watershed that supplies New York City, a moratorium on that type of drilling is in effect until the state completes an environmental impact assessment of hydraulic fracturing, expected any day now.
Other accidents associated with fracking occur above ground. The three spills last week in Dimock were of liquid gels that are concentrates of the fracking fluid; such gels are usually mixed with water to lubricate the fracking process. More than 8,000 gallons of a fracking gel polluted a wetland and caused a fish kill.
Fracking fluid has also been named the possible cause of a massive fish kill earlier this month in Dunkard Creek in western Pennsylvania and West Virginia that killed 161 species of aquatic life including freshwater mussels, salamanders, crayfish and aquatic insects, and an estimated 10,000 fish.
Although one possible source of the contaminant was a mine water treatment facility, chemical analysis shows that the creek water was similar to the kind of wastewater from fracking – it contained a high total dissolved solids (TDS) count, which is not characteristic of wastewater from mines. The source appears to have been higher upstream than the mine wastewater treatment facility, leading state agencies to believe that drilling wastewater was illegally dumped into the creek.
"People were walking ankle-deep in dead fish," Carluccio said, "and everybody was appalled about what happened."