Carbon Sequestration & Deep Well Injection

National Expert: Monte Markley 

Deep well injection and carbon sequestration (also carbon capture and underground storage or CCUS) are services that permanently isolate fluids and gases in deep geologic formations to ensure these materials stay there and don’t impact useable resources or the environment. It encompasses the practice of geologic consulting, reservoir engineering, and deep drilling to plan, permit and execute projects that support environmental objectives. Our services include compliance monitoring, testing, reporting, and optimization of the geologic sequestration asset.

SCS Engineers has provided wastewater/fluid treatment, isolation, storage, and deep well disposal solutions for over 35 years. During this time, the treatment and disposal of liquid wastes have become increasingly challenging. This is due in part to regulations designed to protect surface and groundwater. Deep well injection is a safe and viable solution when planned and permitted correctly.

Deep well injection is the process of safely storing or disposing of liquids deep underground. It involves drilling beneath drinking water aquifers (1,500 to >3,000 feet deep) to trap the liquid waste under multiple impermeable layers of rock. It requires favorable geology, so it is not suitable for all locations.

However, where the geology permits, deep well injection has considerable advantages, such as:

  • Quickly removes large volumes of liquid – eliminates NPDES permits
  • Provides a long-term solution that can operate over decades
  • Uses proven methods and technologies from the oil and gas industry that meet modern regulatory criteria
  • Provides a financially competitive solution with low ongoing operation and maintenance costs
  • Does not impact drinking water sources, thereby avoiding regulatory issues that affect other alternatives

SCS Engineers has extensive experience with a broad range of successful deep well injection projects, including clients working in these business sectors and industries:

deep well injection system
Injection-control well drilling.
  • Chemical industry
  • Food processing
  • Landfills/waste management
  • Municipalities
  • Mining industry
  • Oil and gas operations
  • Power plants and utilities

Many communities use industrial waste disposal wells for stormwater, large-capacity septic systems, and agricultural drainage. They are regulated and are not allowed to endanger underground sources of drinking water. SCS’s UIC services involve a wide array of underground injection well classifications and include those for carbon sequestration or geologic sequestration strategic to accomplishing CO2 reduction goals in the U.S. The EPA classifies the wells for municipal and industrial use as follows:

  • Class I industrial and municipal waste disposal wells
  • Class II oil and gas related injection wells
  • Class III solution mining wells
  • Class IV hazardous and radioactive waste injection wells
  • Class V wells for non-hazardous fluids
  • Class VI geologic sequestration wells

    deep well injection hazardous waste
    In Illinois, an underground longwall coal mine uses a regulated Class I underground injection well to sequestrate native brine groundwater.

SCS can provide a turnkey solution or assist at any stage of a deep well injection project, including:

  • Planning and Regulation: Our experienced geological engineering team can assess the viability of deep well injection and produce fully costed project plans. Having worked across all EPA regions, we have developed a thorough understanding of the complexities of the Underground Injection Control (UIC) program and its regional variations. Our professionals have also built up good working relationships with many of the regulatory bodies.
  • Drilling and Operation: SCS staff have worked on liquid waste injection wells nationwide and supervised the drilling of dozens of deep wells with horizontal and vertical completions. Whether the liquid waste requires pre-treatment or must be injected under pressure, we have the required knowledge base, built up over decades, to deliver projects safely, on time, and within budget.
  • Monitoring and Safety: SCS can monitor wells during injection and afterward for leakage or contamination. Our commitment to the safety of our clients, employees, and the wider public has earned us an excellent reputation with outside stakeholders and regulators.


What’s in Store for 2024: An Update on the Geologic Carbon Sequestration Project Landscape – 15 minute video


Using Carbon Sequestration and Deep Injection Wells for Industry – 11 minute video


View the complete Carbon Sequestration & Deep Well Injection educational video library here.