INSIGHTi

Carbon Dioxide Pipelines: Safety Issues
June 3, 2022
Carbon dioxide (CO2) pipelines are essential components of carbon capture and storage (CCS) systems
which are proposed to reduce atmospheric emissions of man-made CO2, a greenhouse gas. Pipelines are
needed to transport the CO2 from where it is captured (e.g., power plants) to the underground geologic
formations where it can be stored. Approximately 5,000 miles of pipeline already carry CO2 in the United
States, primarily linking natural CO2 sources to aging oil fields where the CO2 is used for enhanced oil
recovery. However, a much more expansive CO2 pipeline network could be needed for CCS to meet
national goals for greenhouse gas reduction. One recent study suggests that such a network could total
some 66,000 miles of pipeline by 2050, requiring some $170 billion in new capital investment. Because
CO2 in high concentrations can be hazardous to human health, building out a national CO2 pipeline
network raises safety issues which may affect nearby communities and may hinder CCS deployment.
CO2 Pipeline Safety
CO2 occurs naturally in the atmosphere and is produced by the human body, so it is often perceived to be
relatively harmless. However, as concentrations increase, CO2 displaces oxygen—which may cause a
range of negative health impacts, including suffocation. Pipeline CO2 also may contain potentially
hazardous contaminants, such as hydrogen sulfide. Because CO2 is colorless, odorless, and heavier than
air, an uncontrolled release may spread undetected near the ground or in confined spaces. Therefore, CO2
pipelines pose a public safety risk, as demonstrated by a 2020 CO2 pipeline rupture in Satartia, MS, which
led to a local evacuation and caused 45 people to be hospitalized.
Transporting CO2 in pipelines is similar to transporting fuels such as natural gas and oil; it requires
attention to pipeline design, protection against corrosion, monitoring for leaks, and safeguards against
overpressure, especially in populated areas. The Pipelines and Hazardous Materials Safety Administration
(PHMSA) within the Department of Transportation (DOT) has statutory authority over CO2 pipeline
safety. PHMSA promulgates and enforces regulations (49 C.F.R. §190, 195-199) for the construction,
operation and maintenance, and spill response planning for CO2 pipelines. Although CO2 is listed as a
Class 2.2 (non-flammable gas) hazardous material under DOT regulations, PHMSA currently applies
safety requirements to CO2 pipelines similar to those for pipelines carrying hazardous liquids such as
crude oil and anhydrous ammonia.
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Prior to the Satartia accident, according to PHMSA statistics, CO2 pipeline operators reported only one
injury and no fatalities caused by regulated pipelines over the last 20 years. However, stakeholders have
argued that PHMSA’s regulations for CO2 pipelines are insufficient with respect to hazard zones around
CO2 releases, potential pipeline fractures, and corrosion of CO2 pipeline steel, among other things. In
response to these criticisms and findings from its own Satartia accident investigation, PHMSA announced
on May 26, 2022, a rulemaking to update its CO2 pipeline safety standards and a research solicitation to
study the impact of CO2 pipeline releases. The agency also issued a Notice of Proposed Violation of its
regulations to the Satartia pipeline operator and proposed $3.9 million in civil penalties.
CO2 Pipeline Opposition
Concerns about CO2 pipeline safety have emerged as an issue for proposed CCS projects, especially in the
Upper Midwest. Summit Carbon Solutions is pursuing a project to carry CO2 from over 30 ethanol plants
in five states through a 2,000-mile pipeline network to a carbon storage site in North Dakota. Navigator
CO2 Ventures is developing a similar project to transport CO2 from ethanol and fertilizer plants in five
states through a 1,300-mile pipeline network to sequestration sites in Illinois. Wolf Carbon Solutions has
proposed a third, 350-mile CO2 pipeline project in Iowa. These pipelines face opposition among affected
landowners and advocacy groups for reasons including risks to public safety. As a consequence, the
developers reportedly have faced resistance securing voluntary agreements with landowners for pipeline
rights-of-way through their properties. Without voluntary agreements, developers may still secure rights-
of-way through eminent domain authority, which typically accompanies siting permits from state utility
regulators with jurisdiction over CO2 pipeline siting. However, CO2 pipeline siting authorities, landowner
rights, and eminent domain laws reside with the states and vary from state to state, so securing rights-of-
way for interstate projects is not guaranteed. Furthermore, there have been regulatory interventions and
legislative efforts to limit state eminent domain authority for such projects.
Considerations for Congress
Consistent with other federal initiatives to promote CCS deployment, Congress has acted to facilitate the
construction of regional CO2 pipeline networks. The USE IT Act (Section 102 of Division S of P.L. 116-
260) clarified CO2 pipeline eligibility for streamlined review of any necessary federal permits (e.g., for
federal lands) which might be required and directed the Council on Environmental Quality to set guidance
to expedite CO2 pipeline development. The Infrastructure Investment and Jobs Act (P.L. 117-58)
establishes a Carbon Dioxide Transportation Infrastructure Finance and Innovation (CIFIA) program for
CO2 pipelines and authorizes $2.1 billion over five years for low-interest CIFIA loans and grants. These
acts and other legislative proposals deal primarily with financial and administrative issues, however,
rather than CO2 pipeline safety.
Given the fundamental need for pipelines in CCS systems, actual or perceived safety risks associated with
CO2 pipelines may limit the potential of CCS as a greenhouse gas mitigation option. Siting opposition due
to safety concerns may prevent CO2 pipeline development in certain localities and increase development
time and costs in others. Some advocates have suggested that Congress take a more active role by
directing federal agencies to develop safety regulations specifically tailored to the distinct characteristics
of CO2 pipelines. How PHMSA might update its CO2 pipeline safety standards remains to be seen, but
CO2 pipeline safety, and its implications for CCS deployment, may be an oversight issue for Congress.

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Author Information

Paul W. Parfomak

Specialist in Energy Policy




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