Slurry Injection

Milestone operates the largest network of slurry injection facilities in the U.S., offering advanced sequestration solutions that permanently trap hydrocarbons from our customers' waste a mile beneath the Earth’s surface. This process prevents the hydrocarbons from volatilizing into the air as emissions, which would naturally occur if the waste were disposed of through traditional methods like reserve pits and landfarming. The reduction in emissions realized by using our waste sequestration technology significantly exceeds the emissions generated from our operational activities, providing a substantial net carbon benefit.

Our proprietary process ensures compliance with regulations, and provides E&P companies with a robust solution to significantly reduce the risks of soil and groundwater contamination while lowering operational carbon footprints. Milestone enables energy companies to adopt a cleaner, more responsible approach to waste management.

At our slurry injection facilties, we manage a diverse array of energy waste streams for our customers, including drilling fluids (water- and oil-based), flowback, produced saltwater, tank bottoms, and oily/dirty water. These wastes primarily originate from the drilling, completion, and production stages of the oil and gas lifecycle, underscoring our integral role of environmental management within the industry.

Our protection goes deep

Our patented, best-in-class slurry injection process is the most cost-efficient and environmentally secure way to sequester waste from drilling, completion, and production operations. We accept all RCRA-exempt, non-hazardous liquid and slurry waste streams, which are injected into carefully selected geological strata, thousands of feet below the Earth's surface. These permeable strata are capped by massive impermeable layers of rock and shale, blocking any possible migration up into our vital water resources.

E&P companies pump drilling mud down the drill string to lubricate the bit during downhole rotation. Drilling mud is comprised of an oil or water base, emulsifiers, brine, dispersants, and/or gels. As the bit rotates, circulation and pressure of the fluid system moves rock fragments up the wellbore to the surface, where it is processed in a nearby reserve pit (or in a series of storage and separation tanks in a “closed-loop” regulatory system). Approximately 20% of drilling mud is recycled back into the fluid system for future use. Depending on the jurisdiction, the remainder is either disposed of onsite via reserve pit or land farming, or it is transported to a permitted disposal facility.

A diagram of the various layers of safety protecting the environment from slurry inejction sites.

Overly engineered for full assurance

We design our slurry injection facilities to go above and beyond in making sure energy waste is safely sequestered deep below the Earth’s surface. After drilling the injection well, we install multiple layers of steel casing and cement them in place, creating an impermeable barrier between the wellbore and surrounding groundwater and strata. We also perform regular maintenance and testing of the facility, and monitor the surrounding groundwater, to ensure wellbore integrity remains intact.

Milestone’s state-of-the-art Class II slurry injection facilities are designed to handle drilling waste that is primarily liquid. Our surface equipment extracts a small fraction of incidental solids from the mud and slurry volume we receive, which we send to our landfills or others nearby. Our landfills handle both incidental solid and liquid waste streams. To prevent leakage at our landfills, we utilize advanced liner technologies and monitoring systems. Liquid waste delivered to the facilities also undergoes a dehydration or bulking process before disposal.

A shot of pipes performing slurry injections.

Carbon sequestration is all we’ve ever done

Since its inception, Milestone has helped energy companies reduce their carbon impact, long before this issue gained the urgency it has today. Over those decades we have perfected our processes. Our locations are meticulously chosen to deliver the best of customer convenience and environmental protection. Our surface handling procedures are state-of-the-art. And our wells are engineered and constructed to perform and last. Milestone simply offers the most cost-effective, environmentally secure waste sequestration option.

Leading Forward For Stakeholders

Whether you are an operator, a landowner, or a policymaker, Milestone knows you are a key stakeholder in our mission. See how we are leading the charge in secure energy waste management and carbon sequestration.

Oil Well on farmland