374Water advances St. Cloud PFAS destruction pilot into Phase 4

374Water said its mobile AirSCWO system completed three phases of a St. Cloud, Minnesota deployment and has moved into a fourth phase focused on a new blended waste stream. The pilot is part of Minnesota’s evaluation of AirSCWO for permanent PFAS destruction and could help determine whether the technology moves into broader commercial use.

Why it matters: - The St. Cloud pilot is helping Minnesota assess whether 374Water’s AirSCWO system can permanently destroy PFAS-laden waste. - A successful program could support broader adoption of the mobile system and recurring service revenue. - The campaign also tests whether AirSCWO can handle multiple biosolids and blended waste streams at a municipal facility.

What happened: - 374Water said it completed Phase 3 of its mobile AirSCWO deployment in St. Cloud, Minnesota, and began Phase 4 on August 10. - The work is taking place at the City of St. Cloud’s Nutrient, Energy, and Water Recovery Facility. - The deployment is covered by a $600,000 Waste Destruction Services contract with the City of St. Cloud. - Barr Engineering is partnering on the project. - The pilot is part of Minnesota’s evaluation of AirSCWO for PFAS destruction, supported by the Legislative-Citizen Commission on Minnesota Resources and the state’s Environment and Natural Resources Trust Fund.

The details: - Phases 1 through 3 ran from June 1 through July 31. - The first three phases treated Class B biosolids, Class A biosolids and pre-digestion sludge. - 374Water said Phase 3 ended with no operational issues. - The company is now analyzing performance data from the campaign. - The company said the deployment has produced preliminary destruction results and a performance dataset across multiple feedstocks and operating conditions. - Phase 4 is treating Class B biosolids blended with spent granular activated carbon from a drinking water purification plant in Cottage Grove, Minnesota. - Spent GAC is a disposal challenge because it can hold captured PFAS. - The company said its mobile system is designed to process solids and blended waste streams. - Raj Melkote, 374Water’s chief technology officer, said the project is notable for its mass and energy balances and for sampling designed to track 96 PFAS species, more than twice the number measured under EPA Method 1633. - The company said the University of St. Thomas helped improve instrument accuracy.

Between the lines: - The St. Cloud campaign is being used as both a technical demo and a commercial proof point. - 374Water is signaling that success in a municipal PFAS project could translate into a repeatable mobile services model. - The focus on blended waste streams suggests the company is trying to show the system can handle more complex, real-world disposal problems. - 374Water also said demand is building across multiple end markets, but that remains a forward-looking view.

What's next: - 374Water said it will continue sharing updates on pilot performance and follow-on mobile deployments. - The company expects the St. Cloud pilot to inform Minnesota’s broader assessment of AirSCWO for permanent PFAS destruction. - 374Water said a mobile AirSCWO unit could generate between $500,000 and $1.5 million in annual revenue per unit, depending on deployment cadence, waste stream composition and contract structure. - The company believes the St. Cloud campaign could support multiple millions of dollars in revenue over time, including recurring annual revenue from operations and services. - The solutions team is developing additional mobile deployments to show the system’s commercial capabilities.

The bottom line: - The St. Cloud project has moved from proving the system can run cleanly to testing whether it can become a scalable PFAS destruction business.