The science behind fracking

The science behind the process of extracting natural gas from the ground known as hydraulic fracturing, or “fracking,” is not always clear-cut, according to Associate Professor of Geological and Marine Sciences Dr. Reed Schwimmer.

A recent panel sponsored by Rider’s Office of Sustainability debated the pros and cons of the process, now being applied to the Marcellus Shale. Stretching from West Virginia through Pennsylvania to New York, this formation has been determined to contain a considerable amount of natural gas.

“Because gas and oil are present in shales, research is focused on trying to produce from them,” Schwimmer said.

The production already has been impressive, making advocates see hope for energy independence, thousands of jobs, and help for the environment as natural gas replaces coal.

The Marcellus Shale formed during the Devonian period, approximately 400 million years ago. When the rock first eroded it was mud. According to Schwimmer, after thousands of years, the mud turned to sediment. After millions of years of pressure, that sediment became natural gas.

Until recently, shale rocks were not considered producible because they are impermeable unless fractured. For years the technology hadn’t been sufficiently developed to open the rocks. The development hydraulic fracturing, however, changed that equation.

Extracting the gas using fracking involves drilling a well thousands of feet deep, then injecting millions of gallons of water, typically drawn from local streams and ponds, as well as sand and chemicals, at high pressures. Some kinds of shale rocks, such as sandstone and limestone reservoirs, contain lots of pore spaces, which release shale gas when broken open.

Though the wells are cased, there is a fear of leaks. According to the EPA, if a fracking well leaks underground, the mix of sand, chemicals and water used to break the shale can escape into aquifers. Thus drinking water might become contaminated with the chemicals injected into the well.

In addition, fracking results in contaminated wastewater, which can pollute both the ground water and the air. At least 5 million gallons of water are required to frack each well. About 70 percent of that water stays underground, while 30 percent is released back out into the environment.

“There’s no law in Pennsylvania saying the oil companies have to disclose what chemicals they use to get the gas from the Marcellus Shale,” Schwimmer stated, adding, “We don’t know exactly what they’re using or how they’re disposing of these chemicals afterwards.”

George Stark, director of external relations at Cabot Oil and Gas Corp., says the company discloses the chemicals it uses during fracking, and that these chemicals are “as harmless as those in dish soap.” Stark maintained that Cabot recycles all of its water used in drilling, and that the solid steel casings on the wells ensure that nothing leaks into the surrounding aquifers.

However, information about Cabot’s use of chemicals on lists dangerous chemicals such as hydrochloric acid, methanol, hydrotreated light distillate and ethylene glycol.  According the EPA website, these chemicals – some of which can be found in fertilizers, dyes and antifreeze – can cause such hazardous effects as corrosion of the eyes, skin and mucous membranes, dental discoloration and erosion, blurred vision, headache, dizziness and nausea.

Moreover, during the extraction process, unburned natural gas can escape into the air, contributing to global warming, and companies often burn off excess natural gas in a process that can pollute the air.

Typically, a company will sign a lease with a property owner that lasts from five to seven years. While the actually drilling process takes 12 to 15 days, it can take a company up to five years to begin drilling on a site. In part because the process is new, there is very little governmental regulation or oversight.

This is what concerns Pennsylvania House Rep. Steve Santarsiero (D-Lower Makefield). Thousands of Pennsylvanians have been faced with the decision of whether to allow fracking on their land.

“If you’re a local official, you have constituents, neighbors saying I don’t want this near my house,” Santarsiero said. “Now under state law the local official has no control over it.”

Issues include how close to homes the drilling takes place, and the source of the water used to force the gas out of the shale. Santarsiero has tried to pass legislation in the House to regulate the amount of water taken out of the ground and serviced by the industry. Both times the bill failed.

“I can tell you, with respect to Pennsylvania, it’s a problem,” Santarsiero said of the state’s current drilling regulations.

The environmental concerns have been noticed on the national level. Because of the “Halliburton Loophole,” the natural gas industry is exempt from the Safe Water Drinking Act and the Clean Water Act. Currently Sen. Bob Casey (D-Pa.) and Rep. Diana DeGette (D-Colo.) have introduced legislation to repeal the loophole. Santarsiero has pushed for a severance tax on the industry as well as other measures to reduce the environmental burden on residents.

Both Schwimmer and Santarsiero agree that, once natural gas has been extracted from the earth, it is preferable to other fossil fuels. “Natural gas burns 30 percent cleaner than diesel and 50 percent cleaner than coal,” said Santarsiero.  However, he suggested taking a break from drilling to further research the effects of fracking and how to do so safely, as well as enforcing stricter regulations at the state and federal level to ensure the environment is protected.

“I’d like to see a moratorium until we can be certain this isn’t harmful,” Santarsiero said.

Schwimmer agreed that the process of extraction needs more research. “There are lots of issues raised which point towards a need to take a pause and research this,” he stated.

Moreover, he added, “Oil is a non-renewable source which takes millions of years to produce. Once we take it out, it’s done.”

This story was reported by Tom Scully, ’12; Lisa Henderson, ’12; Marissa DeSantis, ’12,  Kristy Grinere, ’13; and Joe Petrizzo, ’13.

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