Hydraulic fracturing, or fracking, as it is commonly known, is a technology that has been in use for more than 60 years. Hydraulic fracturing is essential to producing oil and natural gas resources from tight rock and shale formations. Without it, oil and natural gas production cannot economically occur.
Anadarko’s commitment to sustainable development is readily apparent in our innovative hydraulic fracturing operations, which are conducted with a commitment to stakeholder engagement and Health, Safety & Environment (HSE) excellence. In 2014, Anadarko participated in the drilling about 850 wells onshore in the U.S. – approximately 90 percent of which required hydraulic fracturing.
Hydraulic fracturing involves the injection of fluid (generally consisting of water, sand and a proportionately small amount of additives) under pressure through multiple protective layers of steel pipe, cement and rock into a pre-determined oil or natural gas-bearing formation. The water and pressure open microscopic pathways, which are the width of a human hair and propped open by grains of sand. These pathways allow the natural gas or oil to flow through the wellbore to ultimately be produced at the surface. Hydraulic fracturing is generally applied to formations that are more than a mile below the surface (4,000 to 14,000 feet); whereas, potential sources of ground water typically reside much closer to the surface (between 100 and 500 feet). For a general demonstration of the hydraulic-fracturing process, please view this informational video at Energy From Shale.
To ensure wellbore integrity in our U.S. onshore assets, we work to exceed the minimum requirements for cement tops so that zones that could affect groundwater are covered. Cement is either brought to surface or a temperature log is run. In Pennsylvania, specifically, an intermediate casing (steel pipe) is run to 2,000 feet for the sole purpose of mitigating the possibility of gas migration. All steel pipe is pressure tested before drillout, and in many cases the surface casing is tested a second time prior to running intermediate casing. Additionally, centrilizers are used for all surface casing strings and cement slurries are tested on multiple occasions for specified properties prior to being pumped downhole. Finally, we source our steel pipe from respected steel suppliers with the highest standards for manufacturing quality assurance and quality control.
Hydraulic Fracturing Committee
In October 2012, Anadarko formed an internal Hydraulic Fracturing Committee that assists the company’s management in continuously monitoring, evaluating and addressing matters related to its hydraulic fracturing operations.
What’s in It?
The ingredients used in fracking fluids vary according to geology. In general terms, water makes up more than 90 percent of the solution; sand or proppant constitutes approximately 9 percent; and additives make up less than 1 percent of the total volume. The relatively small amount of additives generally consists of friction reducers, biocides to prevent bacterial development and scale inhibitors. This pie chart available at FracFocus shows a general breakout of typical ingredients.
Anadarko supports the public sharing of the ingredients used in hydraulic fracturing. We were instrumental in the creation of the Ground Water Protection Council’s hydraulic fracturing online registry, which makes this information available to anyone, any time at FracFocus.
Anadarko is currently the most active participant in FracFocus with data uploaded for more than 6,000 operated wells. Since 2012, Anadarko has reported approximately 100 percent of its U.S. onshore wells that have been hydraulically fractured to FracFocus.
As part of Anadarko’s commitment to data integrity and disclosure of chemicals used in our hydraulic fracturing process, we believe periodic reviews of the data posted to FracFocus is important. The reviews enable us to identify areas for improvement in efficiency and they provide opportunities to strengthen our quality-control systems. These improvements help prevent potential issues by improving clarity and accuracy.
Anadarko has a strict policy against using diesel fuel in fracking fluids and has communicated this policy to its company’s contract service providers.
In addition, with the guidance of the company's HF Committee and in cooperation with its service providers, Anadarko is continuously working to reduce the toxicity of all fracking fluids, including reducing and/or eliminating BTEX as an ingredient or sub ingredient.
Chemical Assessment Rating Evaluator
Anadarko continually strives to utilize the most advanced technology with the highest environmental profile, which also provides better economic value. We assess both the material and the technique when reviewing different additives and procedures utilized for hydraulic fracturing operations.
Recently, Anadarko began a project to help make this assessment process more reliable and more repeatable. The HSE Department along with chemical specialists and outside environmental consultants collaborated to develop the first version of Chemical Assessment Rating Evaluator (CARE).
CARE provides a rigorous review of chemicals and their relationship to human health based on the United Nations Global Harmonized System of Classification and Labeling of Chemicals, U.S. Environmental Protection Agency (EPA) Guidelines, EPA lists of water and air pollutants and volatile organics, and utilizes other reputable U.S. and European databases. Utilizing the information provided on Material Safety Data Sheets (MSDS), each component of a product can be analyzed, and the score for the product is calculated. Once a specific product has been scored, its relative environmental profile can be compared to other materials that provide the same functionality within the fracturing process. The CARE assessments enable the completion engineers to utilize this quantitative measure to improve the environmental profile of fluids and materials used in the hydraulic fracturing process.
Innovations in Hydraulic Fracturing Technology: Stim Center
Anadarko is pioneering the use of technology in Colorado to conduct hydraulic fracturing for multiple locations from a central facility up to a mile away, called a Stimulation (Stim) Center.
Moving multiple fracking operations to a single location reduces truck traffic and associated emissions, and minimizes the resources required to continuously set up, break down and move operations from one well pad to another. The location of the Stim Center is strategically chosen both to maximize the number of well pads served in an area and to ensure adequate distance from homes, farms, ranches, businesses and other occupied dwellings.
With the ability to transport water via pipeline to and from one Stim Center, Anadarko is able to dramatically reduce the size of a multi-well development pad from 10 acres to less than six acres.
In 2013, Anadarko piloted the Stim Center III using natural gas to power the surface pumping equipment instead of diesel fuel. The trial utilized liquefied natural gas (LNG) to power 70 percent of the needs of the pumping fleet, thereby eliminating the use of 11,250 gallons of diesel fuel and an associated 60,000 lbs of CO2 emissions.
In May of 2014, a “Dual-Fuel” approach of using both diesel and natural gas became standard practice at Stim Center IV, which utilized natural gas sourced entirely from within the Wattenberg field using subsurface pipelines. Through 2014, 63 wells on 20 well pads have been treated using the Dual-Fuel approach, eliminating the need for more than one million gallons of diesel fuel and an associated 5.4 million lbs of CO2 emissions.
Conducting Processes Safely
We work cooperatively with regulators and various agencies to ensure that our drilling, hydraulic fracturing, production and water-handling processes are conducted safely and in accordance with all applicable laws and regulations. These regulations are in place to ensure that produced water and all additives used in the hydraulic fracturing process are properly handled, stored, recycled and/or disposed. Additionally, the laws require that personnel and first responders be made aware of all materials present at each well location.
In addition to the U.S. Occupational Safety and Health Administration (OSHA), other governmental agencies that provide regulatory oversight directly addressing various aspects of fracture stimulation, water management, well integrity and underground injection include:
- Bureau of Land Management (BLM) under the U.S. Department of the Interior (DOI)
- U.S. Department of Transportation (DOT)
- State oil and natural gas regulatory agencies
- State environmental regulatory agencies
Confidential Business Information
As a producer, we are required by state and federal law (set forth in 29 C.F.R. §1910.1200) to keep MSDS, which are prepared and provided by the third-party supplier. The MSDS describe the ingredients used in hydraulic fracturing in detail at each well location. OSHA regulations govern the content of the MSDS. OSHA established the criteria for the disclosure of this information including protecting “trade secret” and "confidential” business information and how this information is reported on the MSDS.
Anadarko does provide the information from the MSDS, which includes all of the ingredients that we are legally permitted to share, to FracFocus. Anadarko is not permitted by law to disclose ingredients used by service contractors that are protected as “trade secret.”
Questions regarding the content of the MSDS should be directed to the supplier that provided it. Anadarko is not responsible for inaccurate and/or incomplete information in the MSDS.