Geologic Sequestration of Carbon Dioxide

U.S. Environmental Protection Agency’s Underground Injection Control Program

The U.S. Environmental Protection Agency’s (EPA’s) Underground Injection Control (UIC) Program is responsible for regulating the construction, operation, permitting, and closure of injection wells that place fluids underground for storage or disposal. Cadmus supported EPA as it developed a proposed rule on geologic sequestration of carbon dioxide (CO2) on a nearly unprecedented nine-month schedule that the EPA manager described as a state of “perpetual emergency.”


Geologic sequestration reduces CO2 emissions to the atmosphere by injecting CO2 captured from an emission source, such as a power plant, into deep subsurface rock formations for long-term storage rather than releasing it into the atmosphere. In October 2007, the EPA administrator asked the UIC Program to issue a proposed rule addressing CO2 injection for geologic sequestration. A quick rulemaking process was needed to provide regulatory guidance to industry as it began to implement this burgeoning technology.

While decades of experience with injection technologies (for example, injection of CO2 for enhanced recovery of oil and gas) provide a strong basis for injection of CO2 for long-term sequestration, this unique application brought about technical and administrative challenges for EPA to address before geologic sequestration could be implemented on a commercial scale.


Cadmus assembled a team of geologists, geochemists, engineers, finance experts, and policy/regulatory experts to provide EPA with technical and regulatory support as it evaluated options for regulating geologic sequestration and the applicability and safety of technologies that can be used to inject and sequester CO2. In a multifaceted effort, Cadmus developed technical papers, solicited expert options, and evaluated the cost implications of a geologic sequestration regulation.

Throughout the rule development process, Cadmus organized summits (including weekend retreats) with EPA staff, where we dedicated full days to reviewing workgroup input and drafting background text for the proposed rule.

To support the rulemaking effort, Cadmus:

  • Developed white papers on regulatory options; technical management strategies for CO2 injection; and relevant technologies for, and implications of, geologic sequestration
  • Supported a series of technical workshops on injection well construction standards and evaluating the geologic suitability of geologic sequestration sites. Cadmus invited experts from around the world to present current research and provide input on issues relevant to regulating CO2 injection wells
  • Evaluated the cost implications to injection well operators and permitting authorities of meeting the proposed requirements and the other regulatory options EPA considered
  • Prepared background text on the proposed requirements that supported development of the preamble to the proposed rule, incorporating explanation of the unique challenges of geologic sequestration and how available technologies can address them


Cadmus’ activities helped EPA increase the knowledge base on geologic sequestration to provide a strong technical and scientific basis for the proposed rule and evaluate the safety and applicability of the technology. EPA met its goal, and the Administrator signed the proposed Federal Requirements Under the Underground Injection Control (UIC) Program for Carbon Dioxide (CO2) Geologic Sequestration (GS) Wells on July 15, 2008.

Cadmus continued to support EPA following proposal of the Class VI Rule. We helped EPA review and respond to thousands of individual public comments on the proposed rule, supported the Agency as it revised the rule to address public comments, and developed guidance and training materials about the final requirements. EPA issued the final Class VI Rule on December 10, 2010.

Information about the rule, including the final rule and many other EPA products that Cadmus also supported, is available on EPA’s website.

Learn more about our outstanding support for geologic sequestration.