Why Tech Startups Aim to Send Your Waste Deep Underground

A startup named Vaulted Deep has partnered with Microsoft to pump millions of tons of treated human waste, fertilizer, and various organic waste deep underground as a method to reduce carbon dioxide levels in the atmosphere. This strategy also mitigates soil contamination from PFAs and other chemical pollutants that can leach from waste.

“We aim to tackle both challenges simultaneously,” Omar Abu Sei stated. “We address the waste issues that compromise local water, air, and land while also contributing to climate solutions.”

In recent years, the Texas-based startup has injected almost 70,000 tons of carbon-rich waste underground, successfully removing over 18,000 tons of carbon dioxide. The technology used is derived from the oil and gas industry, enabling the injection of a slurry comprising liquid, solid, and gas simultaneously. This type of waste typically ends up in landfills or is spread over agricultural fields.

According to Abou-Sayed, if waste is injected at depth, it will eventually release back into the atmosphere, which could potentially liberate millions of tons of carbon. The company capitalizes on this by selling each ton of CO2 removed to businesses or governmental entities.

The contract with Microsoft targets the removal of 4.9 million tons of CO2 over the next 12 years, addressing challenges in the carbon removal sector that attract customers. Microsoft aims to be carbon negative by 2030 and has purchased more carbon removal credits than any other organization.

Abou-Sayed mentions that this agreement will enable Vaulted Deep to identify new injection sites beyond its existing two locations. One site injects “biosolids” remaining from treated wastewater approximately 1,600 meters below the surface in Los Angeles, while the second site in Hutchinson, Kansas, pumps human waste, fertilizer, and organic materials like paper sludge into salt caverns located hundreds of meters underground.

According to one report, the global production of organic waste is substantial enough to facilitate this process and potentially eliminate up to 5 billion tons of CO2 annually.

Vaulted Deep’s mission is to ensure that the maximum amount of waste can be accessed, particularly targeting wet solid slurries that have limited disposal options. “We have developed expertise in identifying where these smooth waste materials can be found,” explains Abou-Sayed. Often, they offer to manage waste disposal at no cost or even provide payment to waste generators.

With high concentrations of nitrogen and PFAs found in waste, storing waste underground instead of spreading it on fields or sending it to landfills can significantly lower surface contamination levels. Many municipalities have faced challenges in finding conventional disposal methods due to stricter PFAs pollution regulations.

“This is a highly innovative approach,” commented Diana Oviedo Valgas from the Stroudwater Research Center in Pennsylvania. “We need diverse strategies to address contaminants, not just PFAs.” However, she emphasizes that injecting waste underground does not eliminate contaminants. “It’s somewhat concealed,” she adds.

To ensure safety during the injection process, Abou-Sayed noted that all sites will undergo a thorough permitting procedure managed by the U.S. Environmental Protection Agency. This is necessary to demonstrate that leaks from the storage area into groundwater or backflow from the well won’t occur, and to reduce the risk of induced seismic activity during the injection.