On December 19, 2013, the Environmental Protection Agency (EPA) issued a final rule revising the definition of hazardous waste under the Resource Conservation and Recovery Act (RCRA), to conditionally exclude carbon dioxide (CO₂) streams from the definition of hazardous waste, provided that the CO₂ streams are captured from emission sources, are injected underground via Underground Injection Control (UIC) Class VI wells approved for the purpose of geologic sequestration under the Safe Drinking Water Act, and meet certain other conditions. The rule was published in the Federal Register on January 3, 2014 and becomes effective on March 4, 2014 (79 FR 350). This rule provides a degree of regulatory certainty for the management of CO₂ streams, and is part of EPA's continuous efforts to foster industry adoption and deployment of carbon capture and sequestration (CCS) technologies. This rule is complementary to the Class VI rules finalized on December 10, 2010 (75 FR 77230).

This rule finds its origin during the development of the UIC Class VI final rule. During the development of those rules, EPA received numerous comments regarding the potential applicability of RCRA Subtitle C to CO₂ streams being geologically sequestered. Recognizing that the lack of certainty and the potential for the application of RCRA Subtitle C regulations to geological sequestration projects could serve as a hindrance to the deployment of CCS technologies, EPA initiated work to study how CO₂ is captured, transported, and injected in CCS activities. EPA made three determinations as a result of this study.

First, it determined that additional regulations under RCRA Subtitle C would not provide further protections over existing regulatory requirements for generators of CO₂ because the process of capturing and compressing CO₂ prior to delivery to a UIC Class VI facility occurs in a continuous fashion, and therefore, would not involve storage at the generator facility. Second, EPA determined that the Department of Transportation's (DOT) regulations (Transportation of Hazardous Liquids by Pipeline, 49 CFR 195) sufficiently addressed risks posed by pipelines in a manner that is consistent with RCRA's goals, and therefore, concluded that additional regulations under RCRA served no purpose for the transportation of CO₂. Having addressed regulatory issues associated with generation, storage and transportation, EPA then looked at injection of CO₂ under the UIC Class VI rules. Yet again, EPA concluded that regulations under RCRA Subtitle C would be duplicative and unnecessary, as the UIC Class VI rules sufficiently protected human health and the environment.

Accordingly, 40 CFR §261.4 is amended by adding an exclusion from the definition of hazardous waste for CO₂ streams that would otherwise be regulated as hazardous waste under RCRA Subtitle C, and that are captured and transported for purposes of injection into an underground injection well subject to the requirements for UIC Class VI wells, provided the following conditions are met:

(1) transportation of the CO₂ stream is in compliance with DOT requirements, including pipeline safety laws set forth in 49 U.S.C. §60101 et seq., DOT regulations set forth in 49 C.F.R. Parts 190-199, and pipeline safety regulations adopted and administered by a state authority pursuant to a certification under 49 U.S.C. §60.105; (2) injection of the CO₂ stream is in compliance with applicable requirements for Class VI UIC wells; (3) no hazardous waste is mixed with the CO₂ stream; and (4) compliance with the above is certified.

It is worth noting that the scope of the final rule is limited to CO₂ injected into UIC Class VI wells for purposes of geologic sequestration. Injection for this purpose is a waste management activity, but due to the exclusion, the waste stream would not qualify as a hazardous waste if the above conditions are met. This rule has no impact on injection of CO₂ into UIC Class II wells for enhanced oil recovery (EOR) because, as EPA acknowledges in this rule, injection for this purpose is not a waste management activity, and therefore, no exclusion is necessary.

While this rule does provide some certainty regarding the regulatory treatment of CO₂ streams, there are still legal issues associated with CO₂ injection that need to be addressed before it can become a widespread control measure for CO₂ emissions. Carbon Capture and Sequestration (CCS) is different from other methods of controlling emissions, due to the fact that responsibility may need to be shared between multiple parties, not just the generator of CO₂ emissions. In order to use CCS as a control measure to sequester CO₂, the generator will likely have to enter into a contract with a third party to transport the CO₂ and demonstrate sequestration. Under such arrangements where the generator is dependent on a third party for compliance, there are always risks of contract breeches, dissolution of the contract parties, or other issues that cannot be foreseen that could threaten the ability of the generator to comply with its emission control obligations while meeting its operational requirements.

Although the step toward more regulatory certainty reflected in this final rule is a productive one, the continued legal and practical uncertainties that are associated with the geologic sequestration of CO₂ that extend beyond the UIC regulatory framework will need to be fully considered as EPA continues to evaluate when CCS may become technically “available” for purposes of establishing control standards for GHGs under the Federal Clean Air Act.