A technician measures stream flow near Nexen’s Dilly Creek shale gas facility in northeastern British Columbia, Canada.
Going with the Flow in the Horn River Basin
As a responsible energy developer, Nexen thinks long term. A major part of our development plan for shale gas resources in northeastern British Columbia, Canada, includes the Horn River Basin Surface Water Management Plan, developed in 2009 to support our application for a long-term water allocation license. Key aspects of this plan:
- Nexen has opted to apply for long-term allocations of variable water volumes, based on actual water availability, which we’ve backed with a life-time water monitoring commitment rather than making annual ad hoc requests for water withdrawals. In this way, our surface water withdrawals in the region are dependent on how much surface water is actually flowing, lessening the impact on aquatic ecosystems. We’ve also advocated successfully for long-term water allocation applications based on availability to be part of the Canadian Association of Petroleum Producer’s shale gas operating practices.
- As part of the Horn River Basin Producers Group, Nexen and other area producers have partnered with Geoscience B.C. and have invested more than $1 million to create a local water monitoring network. We’ve supplemented this by creating a water model using more than 50 years of records from federal and provincial measurement stations. We’re sharing this data with the joint Horn River Basin Producers Group, Geoscience B.C., B.C. Ministry of the Environment, the B.C. Oil and Gas Commission and our interested stakeholders.
- In 2010, we committed to continue the water assessment and monitoring program at our shale gas operations in British Columbia and advance research into new technology that may reduce the use of fresh water. We continue to assess new technology that is expected to enable us to use saline water from a deep aquifer at our shale gas operations.
Pioneering Pressurized Fracturing Technology
Nexen is continually seeking ways to minimize the amount of surface water used in our operations. In 2009, we began investigating the use of groundwater from the Debolt aquifer near our Dilly Creek shale gas development in northeastern British Columbia, Canada, to reduce our use of fresh water. Debolt aquifer water is both saline and sour, meaning it contains hydrogen sulfide (H2S) and other gases. Historically, industry has had to process this water to remove the H2S before it could be used in oil and gas operations, as existing frac pumps are not able to handle the gas contained in the water. This treatment process is expensive and creates a large development footprint.
The solution? Nexen is developing and testing new technology and fracing practices that would enable us to use water from the Debolt aquifer in its natural, untreated state. This technology is called Pressurized Frac on Demand and is essentially pumping the untreated aquifer water at the high pressures necessary for fracturing operations. We have designed a new frac pump allows Nexen to use the Debolt zone as a reservoir for both water storage and water disposal, eliminating the need for a water treatment facility.
In 2014, we continued testing the prototype and will continue to progress this technology over the coming years as our development grows. The system has the potential to allow water from non-potable sources a viable alternative to fresh water for some frac fluids.