Tuesday, November 13, 2012 at 4:21 PM
Ohio's history of oil and gas drilling dates back to the mid-1800s. But the term fracking-the process of blasting water, sand and chemicals into rock to release natural gas-is still relatively new in our vernacular. So how is the drilling and fracking being done today different from the drilling we're all familiar with? In the last story of our "fact checking fracking" series, ideastream's Michelle Kanu explains.
You’ve probably heard conflicting reports about drilling and fracking. A newspaper reports new technology now allows companies to access huge deposits of natural gas trapped in shale rock.
And then from oil and gas executives like Jack Gerard, head of the American Petroleum Institute, you hear:
Gerard: “We’ve been using the technology of hydraulic fracturing for over 65 years in the United States. We have drilled over 1.2 million wells with this technology.”
Is it true that hydraulic fracturing has been used for that long?
Penn State geoscience professor Terry Engelder says, actually it is.
Engelder: “I would describe this as an evolving technology that has evolved almost as long as oil has been produced in the USA starting in 1859.”
Engelder says early oil and gas production started with dropping nitro glycerin down a well to blast open pockets of the resources. In the 1940s, Engelder says two companies experimented with ways to make that process safer, and began pumping a mix of water, sand and chemicals into wells to fracture the rock instead. That’s where the term “hydraulic fracturing” comes from.
Engelder: “The leader in hydraulic fracking is Amoco, but there are service companies as well. Halliburton for example did a lot of this work fairly early on.”
Over the last 60 years, Engelder says the federal government has funded dozens of research projects to help the industry improve its techniques. One of the most substantial developments was the ability to drill down several thousand feet, then turn the bit at a right angle to drill horizontally. That, along with improvements in fracking methods, now allows companies to extract gas from large layers of shale rock that old technology couldn’t effectively crack.
Engelder says the general idea for producing oil and gas hasn’t changed much, but there’s one important difference in all of the activity we hear about in the Marcellus and Utica Shale.
Engelder: “What is brand new is the scale.”
And that’s the direct result of horizontal fracking.
At this site in the northwest corner of Mahoning County, a humming generator supplies electricity to a Consol Energy drilling rig boring a new horizontal gas well. It won’t get to the fracking phase for another few weeks.
Rig manager Pete Nickel explains that the area of fracturing deep underground will be much larger than with a vertical well. He also points out that this drilling site - or well pad - is roughly five acres, about five times the amount of land used for a traditional vertical well. But Nickel says he can access a lot more gas from this one spot.
Nickel: “We’re accessing on this pad approximately a mile of horizontal distance under the earth, so to drill the same amount of vertical wells to exploit the same resources would take ten to twenty vertical well pads.”
While companies can get a better bang for the buck from horizontal wells, many experts say such large scale drilling potentially comes at a much bigger environmental cost.
Beverly Saylor is a geology professor at Case Western Reserve University.
Saylor: There’s a lot more water and chemicals that you’re handling at the surface.”
Saylor says the typical vertical well uses 100,000 gallons of water, while the average horizontal well uses between two and seven million gallons.
Saylor: “That affects the earth in that you need to find that water and extract it and it’s done by withdrawals from either surface waters or ground waters.”
And with so much more water being used, Saylor says, a lot more waste is generated. Most of the water used in the fracking stage stays underground, but once the wells start producing natural gas, some of that water flows back to the surface.
State law requires that most of it be recycled or stored in injection wells deep below ground. But, with Ohio projecting to drill thousands more gas and oil wells over the next few years, it’s still unknown exactly how many injection wells will be needed to handle all of that waste water, and whether they will ultimately contain any environmental threat it may pose.
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