We are committed to the responsible use of water and ensuring that our operations comply with all applicable federal, state and local laws and regulations for the protection of our natural water resources.
The amount of water used in the oil and gas industry as a whole is just 1% of the water used in all other industries combined, as illustrated below:
We use water in operations primarily for:
- Drilling Fluid— a mixture of clay and water is used to carry rock cuttings to the surface, as well as cool the drill bit and control underground pressure.
- Hydraulic Fracturing — a mixture of water, sand and chemical additives is injected into the target formation under pressure to create small fractures in the rock, allowing natural gas or oil to flow to the wellbore. Typical fracturing fluid in our Marcellus Shale operations contains over 99% sand and water.
We have implemented a policy designed to meet and exceed the current state regulations governing water use and protection. Our policy for the Marcellus Shale, our primary operating area, includes the following:
During the well permit application process, all landowners within a minimum of 3,000 feet of a proposed surface location are notified of our intent to drill the well. At the time of such notification, each landowner is given the option of allowing us to test all water sources within 3,000 feet of the well location at our expense. Based on criteria from the Pennsylvania Department of Environmental Protection (PADEP) and work with other oil and gas operators, we have established a predefined set of water testing parameters, which include tests for general water quality indicators, biological factors, metals, dissolved gases, and petroleum constituents. We use independent state accredited laboratories for all our water testing. Landowners are provided with a copy of their results within ten days of Cabot receiving the results.
Processes such as water recycling are essential to the long-term viability of modern natural gas and oil production. Just as importantly, these are imperative for our environment. In our Marcellus Shale operations, which accounted for 60% of our wells drilled in 2012, we currently recycle virtually all of the water generated through our drilling, completion and production operations. In areas that may face water supply limitations and where it is economically prudent, such as in our Eagle Ford Shale operations, available recycle options are evaluated.
Our drilling operations are designed to comply with or exceed all applicable state laws and regulations for the protection of the groundwater located in the shallower zones we are penetrating to get to the oil and gas producing zones. Steel pipe, known as casing, is cemented into place at the uppermost portion of the well for the specific purpose of protecting groundwater. Casing and cementing are critical parts of the well construction that not only protect groundwater, but are also important to ensuring efficient production of natural gas from the well.
Before hydraulic fracturing begins, the cased and cemented well is tested at pressures greater than those that will be used during fracturing operations. Additionally, a cement bond evaluation log using sound waves is conducted to determine if there are flaws in the integrity of the cement in the vertical portion of the well. For more information about our drilling process, see this video.
Much of our nation’s natural gas supplies, including those owned by Cabot, are located in shale formations, which require fracture stimulation to develop. As such, hydraulic fracturing is critical to our operations. In 2013, we implemented our Policy on Hydraulic Fracturing Fluids to document our commitment to use the most environmentally benign hydraulic fracturing fluids that are available and that are effective to produce desired operational results.
We were also instrumental in developing best practices and standards for hydraulic fracturing fluids to be used in the Marcellus Shale as embodied in the April 2012 Recommended Standards and Practices of the Appalachian Shale Recommended Practices Group (ASRPG). We understand the public’s desire to know more about what is involved in our hydraulic fracturing operations, so we voluntarily disclose all chemicals used in hydraulic fracturing activities through www.fracfocus.org.