Are CO2 pipelines safe?

Source: By Mike Soraghan, Carlos Anchondo, E&E News • Posted: Thursday, March 31, 2022

An ethanol refinery in Chancellor, S.D.

An ethanol refinery in Chancellor, S.D. AP Photo/Stephen Groves, file

Companies are striving to lay thousands of miles of pipeline to ship carbon dioxide to storage sites as part of an effort to make ethanol and other energy industries more environmentally friendly.

But a prominent pipeline safety group is warning that the nation’s pipeline safety regulations, enforced by the Pipeline and Hazardous Materials Safety Administration (PHMSA), aren’t up to the task.

The Pipeline Safety Trust (PST), a Bellingham, Wash.-based safety advocacy group, says no regulations govern where the pipelines should be built, limiting dangerous impurities that could lead to accidents or building the pipelines to withstand the unique properties of carbon dioxide under high pressure.

The group described the pipelines as “terribly under-regulated” on its website.

[We] call on PHMSA to close these regulatory absences as quickly as possible to make the upcoming buildout safer to the people who will live around them,” Bill Caram, executive director of the group, said in a statement.

Along with its call for changes, the organization issued a 15-page report yesterday on alleged CO2 pipeline dangers by pipeline safety consultant Richard Kuprewicz.

PHMSA, which is part of the Department of Transportation, did not respond yesterday to a request for comment.

But pipeline groups, carbon capture and storage advocates, and the companies building the projects say the safety concerns are overblown.

John Stoody, vice president of the Association of Oil Pipe Lines (AOPL), said yesterday that the group’s report doesn’t give examples to support the need for more regulations.

“The PST report reflects solutions in search of a problem,” Stoody said. “CO2 pipelines have a demonstrated excellent safety record.”

Currently, there are roughly 5,150 miles of existing CO2 pipelines in the United States, most of which are used for enhanced oil recovery.

Chris Hill, director of environmental and permitting for Summit Carbon Solutions, which is building the largest of three proposed projects in the Midwest, said the PST has raised valid points about some aspects of future CO2 pipelines. But he said they don’t apply to projects currently under consideration.

“We are, in fact, well-regulated,” Hill said. “They’ve identified some important topics that need to be discussed.”

Another industry group, the Consumer Energy Alliance, criticized the PST in a news release for involving Bold Alliance. The environmental group, best known for fighting the Keystone XL pipeline, helped fund the consultant’s report accompanying PST’s call for more regulation.

The report was done by Kuprewicz, a chemical engineer who worked for years in the industry and now consults on pipeline safety.

Carbon capture advocates also say CO2 pipelines are both essential to tackling climate change and very safe.

“CO2 pipelines have an excellent safety record overall — one that easily surpasses other climate-essential energy infrastructure, such as electric transmission and distribution systems,” said Jessie Stolark, public policy and member relations manager at the Carbon Capture Coalition.

Still, Mark Lapka, a farmer and rancher from South Dakota’s McPherson County, is worried about the safety of Summit’s Midwest Carbon Express, a pipeline that would cross about a mile of his property. In an interview yesterday, he said he’s concerned for livestock and people.

“The top concern overall is safety, where you’re pumping such a huge amount of pressure on this pipeline system and the corrosiveness of the material to begin with,” Lapka said

Odorless, colorless

Interest in CCS projects has been driven by a push to decarbonize the economy, strict greenhouse gas emissions rules governing fuels in some states and last year’s infrastructure bill, which included billions in funding for carbon capture demonstration and pilot projects.

Three multibillion-dollar projects in the Midwest are currently driving the debate. Summit’s Midwest Carbon Express is a 2,000-mile, $4.5-billion project that would link ethanol plants in Iowa and other Midwestern states to a carbon storage injection well in North Dakota. The company says it would be the largest carbon capture and storage project in the world and will lower the carbon footprint of ethanol production.

Navigator CO2 Ventures also is proposing a 1,200-mile, $3-billion project that would inject the CO2 in Illinois. Archer-Daniel-Midlands Co.’s 350-mile pipeline would also ship CO2 to a site in Illinois.

The projects have attracted the ire of farmers and other landowners concerned about safety of the pipelines, damage to prime farmland and condemnation of land through eminent domain (Greenwire, Sept. 27, 2021).

Environmental groups also are attacking the drive for more carbon capture, saying companies deploying it are simply trying to extend dependence on fossil fuels (Energywire, Jan. 31). Supporters of the technology say it is critical to achieve climate targets, considering ongoing use of natural gas and other fossil fuels.

CO2 gas is odorless, colorless, doesn’t burn, is heavier than air, and is an asphyxiant and intoxicant, according to Kuprewicz’s report.

So rather than going up in the air like methane or hydrogen, it settles along the ground but is difficult to see. It displaces oxygen and can asphyxiate people caught in a plume.

In 2020, a plume of CO2 mixed with hydrogen sulfide from an enhanced oil recovery operation in Mississippi sent at least 45 people to the hospital.

The Mississippi pipeline carried CO2 for “enhanced oil recovery (EOR),” in which where CO2 is injected into a producing oil field to extract more oil.

Though CO2 pipelines make up a fraction of the country’s 2.7-million-mile pipeline network, Kuprewicz said the United States has more mileage than any other country

Since 2010, there have been 66 incidents on CO2 pipelines with no fatalities, according to PHMSA data. An AOPL analysis found that in that time there were 1.1 CO2 pipeline incidents per 1,000 miles compared to 2.9 crude pipeline incidents per 1,000 miles.

The Midwest Carbon Express will ship the CO2 compressed to a “supercritical” state, which combines the properties of gases and liquids, Hill said. AOPL said most projects would be expected to ship “supercritical” CO2 because of financial incentives.

Federal regulations currently cover CO2 shipped in a supercritical state. But the PST said that PHMSA should be preparing for other pipelines that ship CO2 in liquid or gaseous states, which would not be subject to federal regulation.

Shipping CO2 in a supercritical state, Kuprewicz said in his report, makes pipelines more susceptible to ductile fractures that essentially “unzip” the steel and open great lengths of the pipeline.

The PST said there are numerous other gaps that should be filled if companies are going to be building hundreds or thousands of miles of CO2 pipelines.

They should be odorized like natural gas from utilities to alert people to a leak, regulators should get a better grasp of how broad an area a rupture could endanger, and there should be rules limiting impurities that could corrode or otherwise damage the pipe, the group said.

Pipeline operators should also update their operation and emergency procedure manuals to account for the difference between CO2 pipelines and traditional pipelines, the group said. It also said better rules are needed from governing the conversion of oil or gas pipelines to transporting CO2. 

|