With more rocket launches comes more cleanup

When two rockets crash-landed during test launches at a remote spaceport on Alaska’s Kodiak Island in 2018, the unspent fuel on board bled into the ground at the launch site, contaminating more than 230 tons of soil. As the commercial space industry booms, the botched launches illustrate another complication the industry will have to figure out: how to clean up the trail of pollution it leaves behind.

The rockets quickly came down where they launched at the Pacific Spaceport Complex. That’s where Astra Space, a relatively new venture that also goes by the name Stealth Space Company, held its first attempts at a suborbital launch in 2018, and both failed, New Scientist reported on September 30th. Astra Space didn’t respond to The Verge’s requests for an interview.

Fuel spills like those on Kodiak Island will probably kill plants, animals, and even bacteria and nematodes in the soil. Even successful launches can spread heavy metals across the surrounding land. If left untreated, pollutants can build up in the bodies of animals and leach into groundwater where it could pose risks to people, too. Reviving places doused in fuel and heavy metals from rockets can take immense amounts of time, energy, and money. But it’s increasingly necessary as more rockets head into the sky.

“If you have a large spill of something like refined kerosene, it’s going to have a pretty strong impact on all the biological systems,” Lee Newman, an associate professor at the State University of New York’s College of Environment Science and Forestry, tells The Verge.

Alaska Aerospace Corporation hired a contracted soil remediation company and worked with the Alaska Department of Environmental Conservation to come up with a plan for cleaning up the refined kerosene spill on site. It ultimately decided that the most prudent way to take care of the problem and prevent further harm was to get the soil off site and send it to Anchorage for treatment. Digging up and hauling the dirty soil away can sometimes be the quickest way to clean up the area and prevent contamination from spreading, experts say.

“Sometimes rockets don’t perform as everyone fully expects,” Mark Lester, president & CEO of the Alaska Aerospace Corporation, which owns and operates the spaceport, says of the Astra launch failures. “This demonstrates the space community, the spaceport’s responsibility to get after taking care of the environment when things go awry.”

As the commercial space industry grows, it may need to speed forward with methods of protecting the communities and environment around its launches, too. In the past, according to Lester, the facility only averaged one launch a year. But he says it could soon be hitting the facility’s maximum of nine a year. And with more launch sites, like Spaceport Camden in Georgia and the Virgin Galactic spaceport in New Mexico, popping up across remote parts of the US, spills that need to be tidied up could mushroom, too.

To deal with the contamination in Alaska, New Scientist reports that the dirty soil at Pacific Spaceport was heated up to nearly 600 degrees Fahrenheit in order to vaporize residual hydrocarbons. Then, a thermal oxidizer, which is commonly used for air pollution control, broke down the resulting gases with heat reaching almost 1,600 degrees Fahrenheit, which is about the temperature it takes to melt bronze.

Treating the soil with such high temperatures burns off the fuel, but it doesn’t revive the soil. The structure of the soil has been altered, and any living organisms in it have been killed. “You can’t just take it back and dump it in the spot where you dug it up from because you’re not going to be able to get anything growing in it again,” Newman says. Most of the time, treated soil gets sent to the landfill.

Lester says that the Pacific Spaceport Complex in Alaska did consider another option: using plants and microbes in the soil to break down large chain hydrocarbon molecules in kerosene. This option — called phytoremediation when used with plants and bioremediation with microbes — takes much longer, and Lester says that, ultimately, the climate on Kodiak Island wasn’t ideal for this method. But experts say it can be a good way of actually repairing the environment, especially at the edges of a spill where the concentration of pollution isn’t as high. “You’re reclaiming the ecosystem, because you’re using native plants whenever possible to try to nourish the bacteria that are doing the breakdown there. So we’ve got lower costs, less side effect impacts, and you’re preserving the ecology,” Newman says.

Other spaceports have already put these biology-based interventions to work. NASA’s Kennedy Space Center in Florida sits in the middle of a national wildlife refuge. Unlike the unspent fuel that spilled as a result of the Astra crash landings, most launches leave behind a trail of heavy metals like iron and manganese.

Some plants used in phytoremediation, like ryegrass, readily absorb the heavy metals that can be left behind by rockets. That’s important since it may not be so good for animals and other wildlife. In 2014, one researcher found that alligators near Kennedy Space Center had higher levels of heavy metals in their livers. “These are plants that are able to take high levels of heavy metals without apparently being affected adversely. Such plants may not die. As a matter of fact, they may just thrive,” says Olayinka Nwachukwu a soil scientist at the Michael Okpara University of Agriculture, Umudike, Nigeria.

To date, the space agency tells The Verge that it’s remediated 12,754 tons of soil at Kennedy Space Center, some of which was done through bioremediation. NASA has also put systems in place that use pressurized air to treat groundwater pollution.

There is a lot to conserve on the public land that surrounds these launch sites, which is why cleaning up after launches will continue to be an important issue as the space industry grows. According to the Space Center’s website, the refuge around Kennedy is home to some of the highest numbers of threatened and endangered species in the US, including the West Indian manatee and wood stork. Kodiak Island, where the Pacific Spaceport Complex sits, is called the “emerald isle” for its lush greenery. The Alaskan island is a surprising destination for surfers, and it’s home to a sub-species of brown bears that have been isolated on the island for the last 1,200 years. “There’s no palm trees but it’s very green, it’s beautiful,” Lester tells The Verge. “People pick berries on the spaceport.”