In February 2020, a cloud of gas washed over Sartartia, Mississippi, causing residents to pass out on the spot and sending nearly 50 people to local hospitals. Unbeknownst to the residents, a carbon dioxide pipeline half a mile away from the town had ruptured, sending a cloud of CO2 washing over the community. Rescuers were forced to don protective gas masks as cars stalled, unable to run without oxygen.
As carbon capture and storage—the process of capturing CO2 emissions from power plants and other industrial sites, then storing it permanently underground—is increasingly floated as an important component of decarbonization, pipelines carrying CO2 like the one in Sartartia could become more common. And there are disturbingly few national safety regulations in place, despite the pace of changes being made.
“There are so many gaping regulatory holes that need to be filled, and so much R&D that needs to be done,” said Bill Caram, the executive director of the Pipeline Safety Trust, a nonprofit that focuses on safety issues and regulations.
While the Trust has investigated the potential dangers of pipelines for years, a report on the Sartartia accident published last year in the Huffington Post, Caram said, was a wake-up call for them to look at regulations around CO2 pipelines in particular. The fossil fuel and pipeline industries scrambled to respond to the Trust’s report, issued earlier this year, on the almost total lack of safety regulations for these critical pieces of infrastructure.
What are carbon dioxide pipelines?
CO2 pipelines are already in operation across the country, with fortunately few safety incidents like the one in Mississippi.
“The PST report reflects solutions in search of a problem,” John Stoody, vice president of the Association of Oil Pipe Lines (AOPL), told E&E News. “CO2 pipelines have a demonstrated excellent safety record.”
While CO2 pipelines may have a good safety record now, that’s not saying a lot. Currently, there are only about 5,000 miles of CO2 pipelines in the U.S.—a tiny number compared to the 2 million miles of natural gas pipelines. The vast majority of those pipelines, Caram explained, exist to transport CO2 from one point, usually from natural reservoirs, to oilfields a relatively short distance away, for what’s known as enhanced oil recovery, or the process of injecting CO2 into a well to get more oil out of it.
But the status quo looks poised to change fast. There are currently two major pipeline projects being proposed in the Midwest that could signal the changes to come. A pipeline network owned by a company called Navigator Ventures is proposing to transport CO2 1,300 miles throughout five states; the company claims the project will have the capacity to transport and store 15 million tons of CO2 each year. Summit Carbon Solutions, meanwhile, is looking to build a 2,000-mile pipeline throughout five states—four of which overlap with the Navigator project. These two projects alone will almost double the length of CO2 pipelines in the U.S. And there are bound to be more pipelines built: One possible nationwide decarbonization scenario proposed last year by Princeton University calls for more than 60,000 miles of new CO2 storage to be built for a broad deployment of carbon capture.
These pipelines look a lot different than the ones that currently exist in the U.S. Rather than transporting CO2 from point A to point B, these new CO2 pipelines will collect CO2 from lots of different industrial customers, taking it hundreds of miles away for storage. The pipeline that ruptured in Sartartia, for instance, was just over 30 miles long, taking CO2 from an extinct underground volcano to an oilfield in Mississippi. By contrast, the Summit Carbon pipeline will branch over hundreds of miles to collect CO2 from more than 30 industrial facilities across the region, transporting it to a site in North Dakota to be injected underground.
Pipelines like these are made newly profitable by the rapidly expanding push to increase carbon capture and storage. As the world accelerates toward climate action, lots of industrial actors and polluters have begun to ramp up efforts to capture the emissions from their facilities as part of their “net zero” plans. (Exxon, for instance, is pushing an ambitious plan to turn areas of industrial Houston into a $100 billion carbon capture “hub.”) Last year, Congress expanded tax credits for carbon capture and sequestration infrastructure, increasing incentives for businesses to invest.
“It’s starting to become profitable to capture CO2 from emissions and just storing it for the tax credit, and not enhanced oil recovery,” Caram said.
The risks of carbon dioxide
Well before Sartartia, the dangers of CO2 clouds were known to the world. In 1986, a lake in Cameroon released an enormous amount of CO2 in a natural process known as a limnic eruption, killing some 1,800 people and thousands of animals. (One survivor recounted how there were no flies on the dead bodies, because the CO2 had suffocated the flies, too.) The explosion released hundreds of thousands of tons of gas—much more CO2 than what would come from a pipeline rupture—but it was nevertheless a wake-up call. Congress directed the Pipeline and Hazardous Materials Safety Administration (PHMSA), which oversees the regulation of the country’s natural gas pipeline network, to also regulate the transport of CO2.
Unfortunately, PHMSA’s solution was pretty simplistic, Caram said—adding CO2 as an afterthought to existing regulations for hazardous materials, despite the numerous factors that make CO2 distinct from other substances we send through pipelines. CO2 is odorless and colorless, meaning people can’t smell or see a leak, is heavier than air, and is unable to ignite like other hazardous materials.
“The fact that it doesn’t ignite sounds like it would make it safer, and in some ways it does,” Caram said. “But because it doesn’t ignite, it can travel long distances.”
That means that CO2 can travel for miles from a pipeline rupture, sneaking up silently on unsuspecting victims. That’s not accounted for in the current pipeline regulations. “Right now, we’re measuring potential impact areas [of a rupture] in feet around a pipeline,” Caram said. “There’s nothing in the regulations about how to calculate a potential impact area for CO2 pipelines.” Some of the other possible reforms the report suggests are similarly pretty basic: adding a colorant and odorant to the CO2, regulations on contaminants that could be harmful to the pipeline, installing mechanisms that could prevent a kind of fracture that would otherwise allow the CO2 to run like “a zipper along the pipeline unzipping the pipeline,” potentially causing a huge rupture.
But even if safety improvements are tightened, over the longer term, there’s a larger question of whether so many new pipelines just to transport and store CO2 are actually necessary—and whether that’s where we should be spending time and effort to act on climate. If we’re going to sink millions of dollars into a climate solution that has serious safety drawbacks, shouldn’t it be for renewable energy, not to prolong the life of fossil fuel plants? And the benefits of even a massive CO2 pipeline buildout would still be limited: those 60,000+ miles of new pipelines proposed by Princeton, for instance, would still only be able to capture and store the equivalent of 15% of the U.S.’s greenhouse gas emissions.
A massive, cross-country collection of CO2 could also be tempting for oil producers who want to use it for enhanced recovery. Both the Midwest projects have said the CO2 is destined for storage only, but there’s no guaranteeing what may come with subsequent pipelines. Capturing CO2 across the country just to use it to get even more oil would be a unique exercise in futility.
Regardless, Caram said that since the report’s release, his organization has had productive conversations with regulators and anticipates that at least some changes will be made before any national pipelines are built.
“It does seem like folks are taking this seriously now, and I hope that’s the case,” Caram said. “I hope some action is taken sooner than later.”