Hydraulic fracturing chemical spills on agricultural land need scrutinyJune 01, 2016
Hydraulic fracturing, a widely used method for extracting oil and gas from otherwise impenetrable shale and rock formations, involves not only underground injections composed mostly of water, but also a mixture of chemical additives. These chemicals range from toxic biocides and surfactants, to corrosion inhibitors and slicking agents, and many are also used by other industries.
A Colorado State University research team desired a deeper understanding of the fate of these chemicals when they are spilled accidentally during either transportation or production in oil and gas operations. These spills, especially in Colorado, often take place on or near agricultural lands.
The researchers set out to discover whether the degradation of these chemicals in agricultural soil are affected by co-contamination. The team consisted of Thomas Borch, a professor in the Department of Soil and Crop Sciences in the College of Agricultural Sciences, with joint appointments in civil and environmental engineering and chemistry; Jens Blotevogel, a research assistant professor in civil and environmental engineering; and their graduate student Molly McLaughlin.
Their results are online in the journal Environmental Science and Technology, published by the American Chemical Society (ACS).
In the paper, Borch, Blotevogel and McLaughlin cite 838 total hydraulic fracturing fluid spills in Colorado, reported to the Colorado Oil and Gas Conservation Commission in 2014. These spills only include those larger than five barrels of fluid when they happen within a well pad, and larger than one barrel when outside a well pad.
For their proof-of-concept experiments, the researchers used reactors to simulate chemical reactions and biodegradation of hydraulic fracturing additives spilled on agricultural soil. Later, they plan to test their conclusions at actual spill sites.
They tested three well-known organic chemicals: polyethylene glycol (PEG), a commonly used surfactant; glutaraldehyde, a biocide that prevents pipe corrosion from microbial activity; and polyacrylamide, a slicking agent that allows hydraulic fracturing fluid to better penetrate shale. They looked at how these chemicals interact both with each other, and with naturally occurring salts underground.
They found that the PEG (surfactant) by itself completely biodegrades within about 70 days, but that in combination with glutaraldehyde (biocide), the PEG stayed in the soil much longer. That biodegradation was fully inhibited by salt concentrations typical for oil and gas extraction activities.
"Our motivation for doing this is because the chemicals often come up as mixtures," Borch said. "While you may see biodegradation of a surfactant under normal circumstances, if you spill that together with a biocide that kills bacteria, maybe you don't break that surfactant down as quickly. And that's exactly what we see. If chemicals don't degrade as quickly, it gives them more time to be transported to groundwater or sensitive surface water."
They also looked at the degradation cycle of glutaraldehyde (biocide), which occurred within about two months. While polyacrylamide stuck around in the soil for six months, it covalently bonded with the glutaraldehyde, effectively lowering the toxicity of the biocide.
The bottom line is that more science is needed around how spilled chemicals interact with each other and the underground chemical environment - and this applies not just to oil and gas extraction, but to many industrial processes, the researchers say. Such follow-up studies could lead to better understanding of the potential uptake of pollutants in crops, or contamination of groundwater and surface water, with the ultimate goal of helping improve human health risk assessment of spills.
"We cannot say our findings are valid for all the different chemicals used worldwide in hydraulic fracturing," Blotevogel said. "There are probably 1,000 different chemicals used globally, and they all behave very differently with respect to how they are broken down."
Borch and Blotevogel previously published a comprehensive review of the biocide toxicity in hydraulic fracturing fluids and have worked together for almost nine years. The ES&T study was supported primarily by CSU's School of Global and Environmental Sustainability (SoGES), a grant from the CSU Water Center, and by the Borch-Hoppess Fund for Environmental Contaminant Research.
Colorado State University
Related Hydraulic Fracturing Articles:
New research suggests hydraulic fracturing and saltwater disposal has limited impact on seismic events.
Engineers at the University of California, Riverside have developed a new way to recover almost 100 percent of the water from highly concentrated salt solutions.
California requires oil and gas producers to disclose chemicals used during hydraulic fracturing activities, enabling scientific and public scrutiny of potential environmental and human health hazards.
As hydraulic fracturing operations expand in Canada and in some parts of the United States, researchers at the 2017 Seismological Society of America's (SSA) Annual Meeting are taking a closer look at ways to minimize hazards from the earthquakes triggered by those operations.
Scientists from The University of Texas at Austin have found that high levels of methane in well water from two counties near Fort Worth are probably from shallow natural gas deposits, not natural gas leaks caused by hydraulic fracturing operations in the underlying Barnett Shale.
Researchers at Karolinska Institutet and KTH Royal Institute of Technology in Sweden have contributed to a recent discovery that the heart is filled with the aid of hydraulic forces, the same as those involved in hydraulic brakes in cars.
Each year, 2 to 16 percent of hydraulically fractured oil and gas wells spill hydrocarbons, chemical-laden water, hydraulic fracturing fluids and other substances, according to a new study.
As part of the Impulsing PAradigm Change through disruptive Technologies Program (ImPACT) Tough Robotics Challenge (Program Manager: Satoshi Tadokoro), which is an initiative of the Cabinet Office Council for Science, Technology and Innovation, the research team including Professor Koichi Suzumori from the Tokyo Institute of Technology and Dr.
Researchers at the University of Alberta have conducted the first-ever study to use hydraulic fracturing fluids to examine effects on aquatic animals, such as rainbow trout.
Hydraulic fracturing has boosted US energy production while coming under scrutiny for its potential environmental impacts, mostly related to the wastewater the method generates.
Related Hydraulic Fracturing Reading:
Hydraulic Fracturing in Unconventional Reservoirs: Theories, Operations, and Economic Analysis
by Hoss Belyadi (Author), Ebrahim Fathi (Author), Fatemeh Belyadi (Author)
Hydraulic Fracturing in Unconventional Reservoirs: Theories, Operations, and Economic Analysis introduces the basic characteristics and theories surrounding hydraulic fracturing and the main process of fracturing in shale, including the main workflow, the details in case analysis, and the fundamental differences between theory, study, and practical operation. The book takes the complex nature of the hydraulic fracturing in unconventional reservoirs and applies a practical approach that can be useds as a workflow for designing fracture treatments in various shale basins across the... View Details
Fracking 101: A Beginner's Guide to Hydraulic Fracturing
by Eric George (Author), Jacqueline George (Foreword)
Fracking, or hydraulic fracturing to give its proper name, has become part of our lives recently, due to the massive exploitation of America’s shale oil and gas fields. Along the way it has stirred up controversy, with passionate opponents fighting against the oil companies. The fight has generated a lot of heat, but not much understanding. This guide, written by some-one who knows what he is talking about takes a detached, neutral view of the subject. Without pushing a view for or against, it provides the factual background you need to form an opinion of your own. An Informed and Neutral... View Details
Hydraulic Fracturing (Emerging Trends and Technologies in Petroleum Engineering)
by Michael Berry Smith (Author), Carl Montgomery (Author)
Hydraulic Fracturing effectively busts the myths associated with hydraulic fracturing. It explains how to properly engineer and optimize a hydraulically fractured well by selecting the right materials, evaluating the economic benefits of the project, and ensuring the safety and success of the people, environment, and equipment. From data estimation to design, operation, and performance management, the text presents a logical, step-by-step process for hydraulic fracturing that aids in proper engineering decision making when stimulating a particular reservoir. Numerous... View Details
Handbook of Hydraulic Fracturing
by James G. Speight (Author)
Presents an up-to-date description of current and new hydraulic fracturing processes
Details Emerging Technologies such as Fracture Treatment Design, Open Hole Fracturing, Screenless Completions, Sand Control, Fracturing Completions and Productivity Covers Environmental Impact issues including Geological Disturbance; Chemicals used in Fracturing; General Chemicals; Toxic Chemicals; and Air, Water, Land, and Health impacts Provides many process diagrams as well as tables of feedstocks and their respective products View Details
Essentials of Hydraulic Fracturing: Vertical & Horizontal Wellbores
by Ralph W. Veatch (Author), George King (Author), Stephen Holditch (Author)
Written by three preeminent petroleum engineers, Essentials of Hydraulic Fracturing focuses on consolidating the fundamental basics of fracturing technology with the new advances in extended horizontal wellbores and fracturing applications. It provides the essentials required to understand fracturing behavior, and offers advice on how to apply that knowledge to fracturing treatment design and application. Essentials of Hydraulic Fracturing is a long-awaited text for petroleum engineering students, industry-wide hydraulic fracturing training courses or seminars, and practicing fracturing... View Details
Hydraulic Fracturing Explained: Evaluation, Implementation, and Challenges (Gulf Drilling)
by Erle C. Donaldson (Author), Waqi Alam (Author), Nasrin Begum (Author)
Rocks mechanics legend Erle Donaldson, along with colleagues Waqi Alam and Nasrin Begum from the oil and gas consultant company Tetrahedron, have authored this handbook on updated fundamentals and more recent technology used during a common hydraulic fracturing procedure. Meant for technical and non-technical professionals interested in the subject of hydraulic fracturing, the book provides a clear and simple explanation of the technology and related issues to promote the safe development of petroleum reserves leading to energy independence throughout the world.View Details
Hydraulic Fracturing Wastewater: Treatment, Reuse, and Disposal
by Frank R. Spellman (Author)
This book provides a balanced discussion about the wastewater generated by hydraulic fracturing operations, and how to manage it. It includes an in-depth discussion of the hydraulic fracturing process, the resulting water cycle, and the potential risks to groundwater, soil, and air. The “fracking” process involves numerous chemicals that could potentially harm human health and the environment, especially if they enter and contaminate drinking water supplies. Treatment, reuse, and disposal options are the focus, and several case studies will be presented. The book also discusses the... View Details
Recent Advances in Hydraulic Fracturing (Monograph Vol 12)
by John L. Gidley (Editor)
Book by View Details
Slick Water: Fracking and One Insider's Stand against the World's Most Powerful Industry
by Andrew Nikiforuk (Author)
The fossil fuel industry and many environmental groups tout hydraulic fracturing fracking” as a panacea, with slick promises of energy independence, greenhouse gas reductions, and benefits to local economies. Yet the controversial technology, which blasts massive volumes of fluids, sand, and chemicals into rock and coal formations, has sparked huge public protests. Slick Water tells the shocking, inspiring story of one woman’s stand to hold government and industry accountable for the damage fracking leaves in its wake.
After energy giant Encana secretly fracked... View Details
Fracturing Horizontal Wells
by Mohamed Y. Soliman (Author), Ron Dusterhoft (Author)
Effectively Apply Modern Fracturing Methods in Horizontal Wells
Improve productivity and maximize natural gas extraction using the practical information contained in this comprehensive guide. Written by world-renowned experts, Fracturing Horizontal Wells features complete details on the latest fracking tools and technologies. Illustrations, tables, and real-world examples are found throughout. Discover how to handle site selection and testing, build accurate simulations, and efficiently extract energy from horizontal sources, including shale formations.... View Details