Awakening the slumbering giant: how horizontal drilling technology brought the Endangered Species Act to bear on hydraulic fracturing.

Author:Robbins, Kalyani
Position:The Law and Policy of Hydraulic Fracturing: Addressing the Issues of the Natural Gas Boom


Hydraulic fracturing (also known as "fracking") is nothing new. It dates back to the 1940s and drew little environmental attention or concern for most of its existence. It is a form of natural gas extraction that involves pumping water, chemicals, and sand slurry into a well at extremely high pressure in order to fracture the surrounding rock formation and prop open passages. This frees up the trapped natural gas to flow from the resulting rock fractures to the production well for capture. Fracking operations have evolved from using a range of 20,000 to 80,000 gallons of water per well to using up to 8 million gallons of water and 75,000 to 320,000 pounds of sand (proppant) per well. (1) Much of this advancement happened in the last two decades, thanks largely to the development of dramatically more advanced drilling technology that allows for horizontal drilling deep under the ground. After drilling downward from the point of entry, the drill turns roughly ninety degrees once deep underground, thereafter traveling parallel to the surface. To visualize this process, imagine a very tall "L" with the long side horizontal underground and the short side's tip at the surface. While the downward drilling goes a substantial distance, the drill goes much further after it turns horizontally, and is thus able to get at exponentially more of the shale rock. This new technology has not only rendered the method far more productive and profitable but has also increased the environmental impact.

The recent development of utility-scale hydraulic fracturing, which has taken place at a gold-rush pace and with a corresponding level of excitement, has raised many new environmental concerns. The issues are quite serious, ranging from drinking water contamination to earthquakes, so it is not surprising that wildlife has not been at the forefront of the alarms. But as it turns out the wildlife problem, and not the contamination of the human water supply, may well be the most ominous for the industry. This seemingly anomalous circumstance stems from the array of regulatory exemptions granted to the industry in the statutes designed to protect human health and the complete absence of such exceptions in the Endangered Species Act (ESA). Indeed, the ESA tends to be the least flexible of environmental statutes. It may not get its due in implementation, but when it is applied, it is fierce and unbending. We are just now gradually learning that the new scale of hydraulic fracturing technology is fraught with potential ESA violations, and early signs suggest that the wildlife agencies and NGOs are poised to halt the activity.


    Traditional oil and gas extraction involves drilling through impervious rock that traps concentrated underground reservoirs of oil and gas. (2) Extraction occurs simply due to the change in pressure caused by the drilling, and this method has always been very economically appealing, resulting in as much exploitation as is permitted. But not all of the earth's coveted fossil fuels sit conveniently in these conventional deposits. Quite a bit is trapped in tiny pores and cracks within otherwise impermeable sedimentary rock formations, such that a similar quantity of the resource is spread out over a much larger area. Shale (which is most often the target of the current fracking boom) is an example of such rock. For this reason, the fossil fuel deposits in shale are far more difficult to reach than those in conventional pooled deposits. This oil (called "tight oil") and gas were thus at one time effectively out of our reach.

    Hydraulic fracturing solves this problem. In order to reach the many tiny deposits throughout the rock, it is fractured by injecting a specially formulated fluid into it with tremendous pressure. This fluid contains sand, coarsely ground walnut shells, and other similarly sized materials to serve as proppant, so that the many cracks created by the immense pressure do not simply close back up the moment the force is reduced or stopped. Although the fracking fluid, or "slickwater," is largely water, it contains many dangerous chemicals in addition to the proppant. The wide variety of chemicals

    are included to perform specific actions, such as the addition of friction reducers which allows a fracturing fluid and proppant to be pumped to the target zone at a higher rate and reduced pressure than by using water alone. In addition to friction reducers, other additives include biocides to prevent microorganism growth and reduce bio-fouling of fractures. Oxygen scavengers and other stabilizers which prevent corrosion of metal pipes, and acids which are used to remove drilling mud damage within the area near wellbore are also common either in fracturing fluids or as part of the fracture treatment, (3) Although the basic idea of fracturing the shale rock to release the gas stored throughout it dates back at least to the 1940s, two major changes in the 1990s made the practice far more efficient. Improvement in fracking fluid is one of them; the other is horizontal technology, allowing the operation to reach far more of the shale as well as to reach shale in locations that were previously inaccessible. These two developments have rendered the practice dramatically more lucrative and have also exponentially increased the quantity of shale gas available for capture. Oil and gas companies saw that there was great profit available, and government regulators saw the amazing potential for domestic energy production, and the boom commenced, with regulatory loopholes designed to pave the way. This paving also sped things along at a break-neck pace, such that the development had already begun to spread across the countryside before substantial environmental analyses could be done.

    The New York State Department of Environmental Conservation provides the following overview of technological milestones for hydraulic fracturing:

    Hydraulic Fracturing Technological Milestones (4) Early Natural gas extracted from shale wells 1900s Vertical wells fractured with foam 1983 First gas well drilled in Barnett Shale in Texas 1980- Cross-linked gel fracturing fluids developed and 1990s used in vertical wells 1991 First horizontal well drilled in Barnett Shale 1991 Orientation of induced fractures identified 1996 Slickwater fracturing fluids introduced 1996 Microseismic post-fracturing mapping developed 1998 Slickwater refracturing of originally gel-fractured wells 2002 Multi-stage slickwater fracturing of horizontal wells 2003 First hydraulic fracturing of Marcellus Shale 2005 Increased emphasis on improving the recovery factor 2007 Use of multi-well pads and cluster drilling The importance of the horizontal drilling technology cannot be overstated. Even with the slickwater and the ability to fracture the rock and collect gas from numerous fissures along the wellbore, when this is done only in a vertical line from the well pad at the surface, it lacks economic value. The shale deposits are relatively thin (albeit deep under the ground) layers, but cover massive (multi-state) horizontal areas and a vertical drill only engages with a tiny area of the rock. As such, the expense of a vertical drilling operation is not justified by the potential gas development. But when the wellbore can turn to the side and follow along this huge area of horizontally laid sedimentary shale rock, it reaches a much larger area. It is not unusual to extend the fracture a full horizontal mile, reaching all of the shale that would have gone untapped in a vertical drilling operation. It is not difficult to see how dramatically more profitable horizontal drilling renders the practice of hydraulic fracturing. It also explains why hydraulic fracturing technology existed but was barely used for half a century, then suddenly exploded onto the scene as if it were something new.

    Given that these developments happened two decades ago, wily are we just beginning to talk about the resulting phenomenon now? Like with most technological advancement, there is a delay from initial discovery or design to the point of peak efficiency. Hydraulic fracturing technology has improved over time, and has only recently become a force to be reckoned with:

    From 2007 to 2009, the average lateral length of horizontal drilling for shale rock resources increased by a factor of five, allowing for a tripling of the initial production rate in some shale formations. This technological advance substantially lowered costs and allowed for greater technical access to the shale gas resource in-place. [As of 2011] in North America, break-even prices for some of the more prolific shales [were] estimated to be as low as $3 per thousand cubic feet (mcf), with a large majority of the resource accessible at below $6/mcf. Ten years ago, costs were three to four times higher. As firms continue to make cost reducing innovations, it is likely that the recoverable resource base is larger than presently estimated. (5) Indeed, when scientists estimated the total amount of shale gas in the world in 1997 (one fourth of which was to be found in North America), less than ten percent was deemed technically recoverable, and even less of it economically so. (6) A decade later, estimates were around forty percent. (7) That recent decade more than quadrupled our technological access to shale gas and corresponding development potential. And from 2008 to 2009, Pennsylvania's number of fracking wells more than quadrupled as well. (8)

    In addition to making the practice of fracking fat" more lucrative, these two new technologies also exacerbated its environmental impact and not just. due to increased fracking activity (though of course that has been substantial). The well pad and other surface...

To continue reading