Regulations for CCS/CO2-EOR

Overview of CCS and CO2-EOR

Carbon capture and storage (CCS) is the process of capturing carbon dioxide (CO2) emissions from power plants and industrial facilities and transporting the CO2 via pipeline to a location where it is injected into an underground reservoir for permanent geologic storage. While CO2 may be injected underground to meet an emissions regulation, it also may be injected for enhanced oil recovery (CO2-EOR). Such projects involve injecting CO2 into existing oil fields to recover additional oil left behind. 

The Role of State-Level Regulations

States issue rules to meet federal requirements for underground CO2 injection and storage (see overview below), and also permit and oversee CO2 injection and storage projects. Several states have long-established regulations for overseeing CO2-EOR, while others are just establishing requirements for CO2-EOR and CCS. Overall, states have a variety of requirements to ensure clear and comprehensive regulatory frameworks for CO2 injection and storage projects. State regulations are displayed on each of the maps below:

  1. Regulatory Authorities for CCS/CO2-EOR
  2. Requirements for Long Term Carbon Dioxide (CO2) Storage
  3. Rules for CO2 Transport and Storage Space
  4. Rules CO2 Injection

Last Updated May 2017

Regulatory Authorities for CCS/CO2-EOR – In many states, there is an existing regulatory regime for carbon dioxide (CO2)-enhanced oil recovery (EOR) projects due to a history of operations there. Some states have also outlined a regulatory regime for pure geological storage of carbon dioxide (CO2). In most cases, a state’s oil and gas agency issues permits and oversees CO2-EOR projects. State environmental agencies may also have jurisdiction over pure geological storage of CO2. 

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CO2 Responsibility Requirements – States have flexibility in regulating carbon dioxide (CO2) injection and storage under the Federal Underground Injection Control program. Some states have passed legislation specifying which state agencies are authorized to regulate Class II (Oil and Gas Related Injection Wells) and Class VI (Wells Used for Geological Sequestration of CO2) underground injection wells and how they may exercise their authority, including specifically which types of financial assurances and other responsibility requirements they may impose on CO2 injection and storage operators.
CO2 Storage Trust Fund – Several states have established a public trust fund to pay for a state’s long-term oversight of geologic storage of carbon dioxide (CO2). These funds are often intended for mitigation of any potential environmental damage arising from geologic storage of CO2. Typically, CO2 geologic storage project operators are to be assessed a fee for each ton of CO2 injected, which is to be deposited into the trust fund.

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Rules Regarding Carbon Dioxide (CO2) Pipelines – A state may exercise its eminent domain authority to condemn private lands for public use. In such cases, compensation to private landowners is required. A state may declare in legislation certain categories of activities, such as CO2 pipelines, eligible for the use of its eminent domain authority. States may also require that CO2 pipelines serve as “common carriers,” meaning they must be open for use by parties other than the owner.
Rules Regarding Pore Space – A state may clarify in legislation who owns the subsurface area, or pore space, where CO2 is injected; it is usually the owner of surface land. Several states enacted laws for the unitization of pore space, which is a process whereby a state will pool the ownership of pore space once a certain percentage of ownership interests (usually a majority) agree to aggregate their ownership interests.

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Rules on Carbon Dioxide injection – Some states have enacted legislation to specify regulatory requirements applicable to carbon dioxide (CO2) injection for carbon dioxide-enhanced oil recovery (CO2-EOR) and geologic storage.  In some states, different regulatory regimes apply to CO2 injection when it is for CO2-EOR and when it is for geologic storage. In other states, the same regulations apply to CO2 injection regardless of whether it is for CO2-EOR or geologic storage. 

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Overview of Federal Regulations for CCS and CO2-EOR

The U.S. Environmental Protection Agency (EPA) administers two programs that establish regulatory requirements for CO2 injection and storage: the Underground Injection Control Program (to protect groundwater) and the Greenhouse Gas Reporting Program (to report air emissions). The requirements of each differ in stringency depending on whether CO2 is being injected for enhanced oil recovery (CO2-EOR) or solely for geologic storage.

The Underground Injection Control (UIC) program ensures that underground CO2 injection does not endanger underground drinking water resources. UIC Class II well requirements cover oil and gas production, while UIC Class VI cover CO2 injection for solely for geologic storage. A state can apply to the EPA for primacy in administering the UIC program within its jurisdiction instead of the EPA. Currently, 41 states have primacy or share primacy with the EPA for permitting Class II wells. No state has applied for primacy to administer Class VI wells to date, but several are expected to do so.

The Greenhouse Gas Reporting Program (GHGRP) creates a framework for reporting CO2 delivered to projects, and for monitoring CO2 that is injected for geologic storage. The GHGRP’s Subpart UU applies to CO2-EOR projects and requires them to report how much CO2 is delivered for underground injection. The GHGRP’s more stringent Subpart RR applies to CO2 injected for geologic storage. In comparison to Subpart UU, Subpart RR requires project operators to report the amount of CO2 actually injected for geologic storage and to develop and implement an EPA-approved plan for ongoing monitoring, reporting, and verification of injected CO2. CO2-EOR operators may opt to report under Subpart RR.

Currently, under the GHGRP, project operators report directly to the EPA, instead of a state agency.

Also see map of state financial incentives for CCS.


[1] For more on the definition of eminent domain -