The energy industry is committed to following principles that allow for the responsible production of America’s natural gas resource via hydraulic fracturing. Rapidly advancing best practices are helping the industry find a sustainable balance.

By James L. Gooding, PhD

Photo by MLADEN ANtoNoV/AFP/GEtty IMAGEs

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A Consol Energy horizontal well drilling rig explores the Marcellus Shale outside the town of Waynesburg, Pa., in April 2012. The tanks in the foreground are used to process drilling fluids while the well is still being drilled, as shown here. Additional equipment will be added when hydraulic fracturing operations begin.

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JIM GOODING is a geoscientist and energy market analyst with the Black & Veatch Management Consulting Division. He earned a PhD in earth and planetary science from the University of New Mexico and has worked as a research scientist as well as a university instructor in geology and hydrology. He is a Registered Professional Geoscientist (State of Texas) and a Certified Man-ager of Quality/Organizational Excellence (American Society for Quality).

e have a “duty to fracture responsi-bly” implores the man who laid the foundation for the shale gas revolution. In his Feb. 20, 2012, blog on FuelFix.com, George P. Mitchell, who pioneered the concept as well as the technology for extracting natural gas from hydrocarbon-bearing shale rocks, provided a splendid review of the reasoned approach needed for sustainable development of the vast prospects of shale gas in North America and around the world. Mitch-ell reminded all stakeholders that it is wrong to deny that a few mistakes have been made just as it is wrong to abandon a unique base of energy resources through misguided regulatory policies driven by erroneous assumptions.

Why then does the subject of hydraulic fracturing seem so rancorous on any given news day? Even a skirmish over spelling has emerged as its own caricature of the conten-tious situation. Media coverage includes “frac” and “frack” as competing abbreviations with seemingly loaded undertones. “Frac” is techni-cally preferred as a short form of “fracture” and is used almost exclusively in petroleum engi-neering literature. But elsewhere “frack” is used abundantly and often as a pejorative favored by industry critics. That regrettable spelling feud provides no solutions.

Hydraulic fracturing is not a new practice, and its risk-reward proposition is open to in-spection and ongoing improvements. Beneficial and responsible recovery of domestic gas re-sources will require aligned efforts between the best industry practices and the most sensible, fact-based regulations.

70 Years of Development

The petroleum technology known as hydrau-lic fracturing began in the 1940s although it became a recognizable topic for public con-versation only after about 2007 when serious

development began for natural gas resources trapped in the Marcellus Shale underlying Pennsylvania. Hydraulic fracturing was first applied to oil and gas reservoirs in sandstone and limestone found in Oklahoma and Texas. Hydraulic fracturing of gas shales began much later and was progressively optimized dur-ing the 1990s and early 2000s, with barely any public notice, in the Barnett Shale underneath north-central Texas.

The persistence of Mitchell Energy & Devel-opment Corp. in the Barnett Shale, beginning in the 1970s, persuaded numerous doubters that natural gas could be reliably extracted from tight, fine-grained “mud rocks” often classified as shales. Shales were traditionally regarded by petroleum geologists as effectively the geo-logic crock-pot cookers for the oil and gas that had migrated eons ago into the reservoirs of conventional interest comprising porous sand-stones and limestones. Until Mitchell proved the concept, petroleum resources remaining in the shale source rocks were considered techni-cally and economically out of reach because the rocks lacked the porosity and permeability needed for gas flow into a well bore.

Mitchell and others showed that the key was to force open—and keep open—small fractures in the underground beds of shale so that gas molecules could be released and captured into a well. The method was to pump pressurized fluids downhole until fractures developed in the shale. The fluids were spiked with small sand grains serving as “proppants” to prop open the stimulated fractures.

To maximize surface area, wells first were drilled vertically to reach the shale bed at depth and then extended horizontally within the thickness of the bed—so hydraulic fracturing technology grew along with the closely associ-ated technology of horizontal drilling. Hydraulic fracturing in the Barnett Shale tested various

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Photo courtEsy oF bEAr crEEk sErVIcEs LLc (www.bEArcrEEksErVIcEs.NEt/hoME)

Material tanks (yellow) and pressurized mixers (red) used to prepare hydraulic fracturing fluids to be sent downhole at a shale-gas well pad.

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fluids, including plain water, water with select-ed additives and even expansive polymer gels.

At the conclusion of a hydraulic fracturing operation, some water returns upward through the wellbore as “flow-back” along with any natural “produced” water released by the shale formation. The amount of wastewater varies but commonly is about 20 to 80 percent of the vol-ume originally sent downhole. The wastewater

typically is heavily laden with salts and is thus classified as brine and regulated accordingly.

By about 2003, the hydraulic fracturing method of choice became “slickwater,” using water with a few minor additives to manage downhole chemistry and prevent clogging. Wastewater disposal mostly relied upon deep injection wells (Class II disposal wells per the U.S. Environmental Protection Agency) and less often on treatment and surface release.

The Barnett-type methods were carried into later shale-gas developments in Arkansas (Fay-etteville Shale), Louisiana (Haynesville Shale) and Pennsylvania (Marcellus Shale) among others. To date, hydraulic fracturing has been successfully applied to more than 15,000 wells in the Barnett Shale and a total of about 10,000 more across six other shale-gas plays.

Substantial Process Improvement

Although substitutes have been proposed, including pressurized carbon dioxide, water-based hydraulic fracturing remains the current

method of choice. Therefore, gas producers and field service companies have invested sub-stantial effort to minimize hydraulic fracturing impacts both on the environment and on their economic performance. The all-in cost of water is a significant consideration.

In a report commissioned by the U.S. Depart-ment of Energy in 2009, the Ground Water Pro-tection Council and ALL Consulting found that a typical shale-gas well requires at least 3 million to 4 million gallons of water for drilling and completion, including hydraulic fracturing. The water transportation and handling can be a lo-gistical challenge as are precautions to prevent wastewater spills—especially in Pennsylvania where geology and regulations do not support injection wells, transportation of wastewater to disposal wells in Ohio is a significant cost.

Research conducted by Black & Veatch showed that shale-gas water costs are higher than for industrial water in the 50 largest U.S. cities. As of 2010, shale-gas developers paid at least 1.4 cents per gallon for source water and another 11 to 16 cents/gallon to handle the wastewater. In contrast, the most expensive industrial water associated with municipali-ties was 0.7 cent/gallon for source water and 1.7 cents/gallon for wastewater. Clearly, shale-gas developers are highly motivated to reduce water costs and have moved toward recycling and on-site treatment to reduce total volumes and transportation needs. The ancillary ben-efits are less truck traffic with its associated air emissions, noise and road wear.

Hydraulic fracturing fluids are customized for the geology of the play and even for fractur-ing sequences (called sub-stages) on a given well. Additives might include five to 10 differ-ent agents; the most common ones are friction reducers to make downhole pumping more efficient, mineral etchers to promote clean fractures, corrosion inhibitors and biocides to prevent scaling or rusting of downhole equip-ment, and, of course, the proppants. Water and proppant (usually silica sand) account for more than 99 percent by weight of the fluid with the remainder being the various chemical additives.

Since about 2006, water treatment has been proven in the field, and scalable, mobile water treatment services for well-pad sites have become a new industry. A few systems have yielded, in special circumstances, treated water, which was permitted by regulators for release

Cluster of water treatment modules deployable at shale-gas well pads to make hydraulic fracturing water reusable and reduce volumes sent into injec-tion wells. Each columnar unit is about 15 feet tall and can be delivered by truck and powered by waste heat or other sources.

Photo courtEsy oF ALtELA INc.

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into streams or rivers. As of 2011, reportedly more than two-thirds of water volumes are being recycled in the Marcellus Shale developments in Pennsylvania. Even so, recycling has its limits and deep-well injection, rather than surface release, remains the destiny of the ultimate leftovers.

Best Practices Can Reduce Risks

Concerns about hydraulic fracturing safety have arisen as numerous state and federal gov-ernment agencies, as well as public watchdog groups, have reacted to rapid growth of shale-gas fields in locations with little or no prior ex-perience with petroleum resource developments. Initially the most frequent issue was whether the large volumes of water required for hydraulic fracturing threatened the adequacy of water supplies needed by other types of users.

Even though 4 million gallons per shale-gas well might seem large, the total volumes are minor compared with other uses, including municipal and agricultural demands. Indeed, a study commissioned by the State of Texas re-ported in 2007 that municipal and agricultural use of groundwater, rather than the Barnett Shale development, presented the greatest risks in ensuring future groundwater availability in north-central Texas.

More recently, the two most commonly cited concerns are whether hydraulic fracturing can contaminate drinking water wells and whether wastewater disposal wells cause damaging earthquakes. Both issues can be effectively ad-dressed through advancement of best practices.

In response to allegations that hydraulic fracturing fluids endanger public health, the industry took the initiative to jointly assemble and disclose details about the fluids through the FracFocus.org website where, as of late 2011, there were 7,000 searchable records provided by 80 participating companies. Each chemical is identified by its Chemical Abstracts Service (CAS) number, which enables cross-checking against multiple sources of publicly available information. What remains propri-etary (and understandable as a trade secret) are the precise ways in which various companies combine the chemicals into customized formu-lations. But there are no longer secrets about the basic ingredients.

A total of more than 1 million underground injection wells (based on EPA statistics) have

been used for different kinds of waste dis-posal over many decades, but since about 2010 some injection wells associated with shale-gas wastewater have been implicated in the occurrence of minor earthquakes. North-central Texas, central Arkansas and eastern Ohio all have experienced magnitude 2 to 3 earthquakes (with one magnitude 4 in Ohio) at locations where wastewater disposal wells have operated, possibly involving minor fault slippage influenced by wastewater injection. The Arkansas and Ohio experiences led to moratoria on certain disposal wells.

Earthquakes occur along faults and, al-though not every fault necessarily causes an earthquake, future pre-project characterization of Class II injection wells might require seismic assessments as is currently required for Class I injection wells. Upgraded best practices also likely will include increased attention to down-hole pumping rates and pressures.

Stewardship of Environment and Stakeholder Confidence

As of early 2012, a multitude of U.S. federal government studies of hydrau-lic fracturing are in progress, including separate reviews by the EPA, DOE and the Depart-ment of the Interior. All of the studies purport to review the safety and environmental ac-ceptability—sometimes with industry input and sometimes not—and to recommend regula-tory policies. One EPA report in 2011 highlighted three sites where hydraulic fracturing was implicated as a possible source of water pollution, including Pavillion, Wyo., which EPA put forward as its strongest case.

Independent studies pub-lished in early 2012 by scientists at The Penn-sylvania State University and at The University of Texas at Austin concluded that little evidence exists to implicate hydraulic fracturing as a systematic threat to groundwater quality. In those cases where drilling-related water pol-lution was most suspect, the cause appeared to be defective well construction rather than a hydraulic fracturing operation.

esponsibleproducers view a

hazard avoided also as a cost avoided so environmental quality and economic perfor-mance again tend toward parallel tracks when best practices are adopted.

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Where and how hydraulic fracturing is most prudently applied depends on geology and hydrology, which are not the same from one state to the next. The most fervent controversies about hydraulic fracturing have occurred in states where regulatory frameworks were inad-equate or outdated in the context of petroleum development. States with extensive petroleum experience have regulated hydraulic fracturing successfully for many decades.

Nonetheless, even the long-tenured petro-leum states have updated their policies and practices in the light of shale-gas develop-ments and have moved uniformly toward more stringent requirements on developers as well as greater public disclosure of hydraulic fracturing details. Since 2011, updated regulations requir-ing higher standards of industry performance and disclosure have been completed or initial-ized in Colorado, Wyoming, Texas, Arkansas, Louisiana, Ohio, Pennsylvania and West Vir-ginia. More recently, North Carolina joined the upgrade movement as its shale-gas potential became apparent.

Responsible producers view a hazard avoided also as a cost avoided so environmen-tal quality and economic performance again tend toward parallel tracks when best practices are adopted. No industry wants to be defined by its few worst actors, and peer pressure can be more effective than litigation in correcting bad practices. Therefore, leading shale-gas develop-ers have moved to raise the performance bar on themselves and their peers. The American Petroleum Institute issued no fewer than five guidance documents for the safe and sustain-able performance of hydraulic fracturing opera-tions. The “Overview of Industry Guidance/Best Practices on Hydraulic Fracturing” is online at API.org. AGA also has dedicated a section of its website, www.aga.org, to the issue. Click on “Our Issues” then “Responsible Natural Gas Resource Development.”

Responsible recovery of domestic gas re-sources will require aligned efforts between the best practices and the most regionally sensible regulations. Given a fact-based approach to hydraulic fracturing, the economy and the envi-ronment both can be winners with shale gas.

Editor’s NotE: For more coverage on this topic, please see “All Together Now,” starting on p. 5 of this issue, and “Clearing the Air” in the April 2012 American Gas.

The Survey Says … Survey respondents weigh in on the value of natural gas and its role in reviving the economy.

By michael A. Bassik

Our nation’s capital remains bullish on natural gas. A march 2012 poll commissioned by the American Gas Association and conducted by Penn schoen Berland found that a resounding 84 percent of Washington, D.c., elites support an increase in domestic natural gas use and exploration.

A majority of those surveyed in march believe that the U.s. govern-ment should be doing more to promote natural gas, and fully 62 percent agree with AGA’s message that natural gas is a clean, abundant and af-fordable energy source that’s good for the economy.

The poll also suggests that effective communications should remind elected officials, journalists, groups that influence policy and others that natural gas diminishes our reliance on foreign oil, lowers energy costs for consumers and reduces carbon emissions.

A related study commissioned by the association found that conversations taking place online, on blogs and across social media outlets like Facebook and Twitter should emphasize the importance of natural gas exploration and, specifically, its ability to lower unemployment and improve the economy.

According to research by Proof integrated communications, an advertising and communica-tions firm that monitors and analyzes online conversations, from november 2011 through February 2012, there have been close to 400,000 posts on hydraulic fracturing in the United states. From politicians, to influential journalists, to environmental-ists and residents living in natural gas communities, each audience has an opinion on the high-profile extraction process. Opponents continue to call for increased regulation while support-ers remind online audiences of the numerous economic benefits of hydraulic fracturing for individuals and the economy at large.

Findings from these two studies were used to help craft messages for AGA’s advertising efforts, which will in part remind elected officials that natural gas is a clean, abundant and affordable domestic energy source. Advertisements are geographically targeted to audiences in Washington, D.c., and began appearing this spring.

MICHAEL A. BASSIK is CEO of Proof Integrated Communications, an advertising and communications firm that monitors and analyzes online conversations.

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