Proper well construction is essential to protect the environment, particularly freshwater aquifers. We use steel casing and cement in the wellbore to create physical barriers and protect drinking water resources. During well construction, we use industry best practices and comply with state rules for drilling and completions.
Marathon Oil’s Environmental Management Standard requires each business unit to develop a plan to conduct pre-drill sampling to evaluate the baseline quality of water sources located within ¼ mile of drill sites. Water sources are tested for a variety of parameters such as basic cations and anions, common naturally-occurring constituents, and indicator constituents that can be found in hydraulic fracturing fluids or produced water.*
Marathon Oil provides notice to nearby well operators of its upcoming hydraulic fracturing operations in accordance with written procedures. When Marathon Oil plans to hydraulically fracture a well near its own operations, or receives notice that a third party will hydraulically fracture a well near its operations, Marathon Oil takes steps to monitor, shut in, and/or decomplete the well as appropriate. These steps are taken to mitigate the risk of communication among wells.*
Hydraulic fracturing involves pumping a mixture of mostly water and sand, and a small amount of additives, under high pressure into the reservoir to create fractures, or cracks, in the target rock formation. This increases the production rate and ultimate recovery of oil and natural gas from a well. Marathon Oil looks for ways to use less freshwater in our hydraulic fracturing operations without negatively impacting well performance and to minimize operational impacts on local watersheds. We pursue alternative sources for water, such as aquifers whose water supply does not meet standards for municipal or agricultural use, and evaluate technologies for recycling and treating produced water for reuse.
To protect surface and groundwater resources and natural habitat, we manage and dispose of our produced fluid waste from hydraulically fractured wells in accordance with all federal, state and local regulations. Fluids are recovered and stored with care to minimize any spills or leaks. In addition, we reuse or dispose of these fluids at locations we have reviewed to verify vendors have proper permits and approvals to operate. Marathon Oil supports state-level disclosure of fracturing fluid components. We worked with other operators and trade organizations to implement FracFocus, a voluntary online chemical registry for hydraulically fractured wells. Marathon Oil has entered all of our wells drilled and hydraulically fractured in the U.S. in FracFocus, a total of 2,504 wells through December 2017. We encourage service companies that work with us to disclose their fracturing fluid components as well. Marathon Oil routinely contractually requires its service companies to disclose their fracturing components to FracFocus as well. Marathon Oil is unable to contractually require a service company to disclose those constituents which are protected by trade secret laws.*
*Updated February 2019
Marathon Oil uses well-established business processes to evaluate climate change risk in our investment decisions, and engages with external stakeholders to understand their perspectives.
Marathon Oil and our workforce were deeply affected by the record-shattering storm. But we cared for each other, our neighbors and communities, while continuing critical business functions and safeguarding our South Texas Eagle Ford asset.
We’re expanding digital oilfield capabilities throughout our U.S. unconventional resource plays. They’re allowing us to automate field operations, transmit and manage large amounts of data, perform site and equipment surveillance remotely, and analyze and optimize operations.
Since 2002, Marathon Oil has been the operator of a world-class integrated gas business in Equatorial Guinea. We’re striving to bring progress, opportunities and national capacity to the community and host nation, while building long-term shareholder value.