We are committed to protecting groundwater and surface water by adhering to strict well integrity procedures and safe water management practices at the surface.
During drilling activities, one of the most important objectives for us is to protect groundwater. To isolate and protect freshwater zones throughout the life of the well, we design and construct new wells with multiple barriers of steel casing and cement. We closely monitor system pressures during drilling and completion activities. When drilling through freshwater zones, we use air or freshwater-based fluids to prevent water contamination. We hold fluids recovered from fracking in tanks or lined pits and manage them in accordance with government-approved methods to ensure safety and environmental protection. Additionally, in some areas we have begun baseline groundwater sampling to assure we have no impact on drinking water aquifers. We plan to expand this program to other areas as new shale resources are developed.
At the end of a well’s productive life, we follow stringent site-closure requirements. These include setting cement plugs and/or mechanical barriers inside the well to isolate and protect freshwater sources.
We implement water management practices to use this vital resource efficiently.
Cooperation in Action
In the Permian Basin of West Texas, ConocoPhillips engineers Ramesh Sharma and Austin Shields recently collaborated on a project to use treated, recycled water during the completions process. Their goal was to utilize "produced water" - water produced normally during the course of drilling activities – instead of fresh water.
Water is scarce in the Permian Basin, where there is little rainfall, and energy companies compete with agriculture for fresh water. Sharma, a Water Solutions staff process engineer, and a multidisciplinary team from the region headed by Shields, a completions engineer, looked at ways to complete wells using "challenged" water – water that is unsuitable for human or agricultural use.
"Produced water is a plentiful resource, especially in the Permian, so it makes sense to use it instead of disposing of it," Sharma said.
In addition to reducing the need for freshwater, the use of produced water means there is no need to transport large quantities of water into the drill site, greatly reducing traffic in the area and wear and tear on local roads.
"We're trying to utilize less freshwater by developing technologies that will allow us to use more challenged water, and we're making good progress. In the Permian Basin pilot test where we used 100% recycled produced water, it cost less than if we'd used freshwater. That's good for the environment, the company and the shareholders,” said Greg Leveille, technology program manager, Unconventional Reservoirs.
Shields and Sharma consider this project just the beginning.
"We're getting experience under our belt. We worked up from using 50% recycled water on the first and 75% on the second well. We used 100 % recycled water to complete the fourth and fifth wells. A few months later we used 90,000 barrels of treated, recycled produced water in 30 stages of hydraulic fracturing," said Sharma.
We also founded the Eagle Ford Water Consortium, a group of oil and natural gas producers that meets regularly to share information about water use planning and to interact with local and state regulators. In addition, using our own research findings and technological advances within the industry, we continually strive to reduce and conserve the water we use in fracking. In the Eagle Ford, we have reduced our water usage by up to 45% by modifying the composition of our fracturing fluid. This change was first implemented in early 2011 and is now applied to all our new Eagle Ford wells.