At A Glance
- Validating Authorities: U.S. Army Engineer Research and Development Center (ERDC) and Arcadis U.S., Inc.
- Destruction Rate: 99.9993% Destruction and Removal Efficiency (DRE) across 42 PFAS compounds in concentrated Aqueous Film-Forming Foam (AFFF).
- Effluent Compliance: Liquid output met EPA Maximum Contaminant Levels (MCLs), permitting direct environmental or sewer discharge.
- Air Quality Advantage: Near-zero stack emissions (0.0005 g/hr volatile fluorinated output) eliminate the need for costly secondary air scrubbing.
- Federal Context: Released under ERDC TR-26-19 via the Army’s Environmental Quality Technology 6.4 Program to remediate legacy defense stockpiles.
An independent federal evaluation has confirmed that supercritical water oxidation can permanently eliminate per- and polyfluoroalkyl substances (PFAS) in legacy military firefighting foams without generating toxic air emissions or dangerous secondary waste.
According to technical report ERDC TR-26-19 released by the U.S. Army Engineer Research and Development Center (ERDC), 374Water’s commercial-scale AirSCWO™ system achieved a 99.9993% PFAS Destruction and Removal Efficiency (DRE) during field trials treating concentrated Aqueous Film-Forming Foam (AFFF).
The validation comes as federal agencies and civil engineering contractors face an unprecedented challenge: disposing of millions of gallons of legacy AFFF stockpiles while complying with strict U.S. Environmental Protection Agency (EPA) drinking water thresholds. Traditional destruction methods—such as high-temperature incineration—often require expensive air-pollution control systems to catch incomplete combustion byproducts or risk relocating contamination.
We’re so glad you are here! Like what you’re reading? Make America’s Engineers a Google preferred news source.Conducted in partnership with engineering firm Arcadis U.S., Inc. at 374Water’s Orlando facility, the demonstration processed raw AFFF concentrate through the AirSCWO 6 unit. Supercritical water oxidation operates beyond water’s thermodynamic critical point—above 374°C (705°F) and 221 bar (3,200 psi)—where water acts as an organic solvent. In this state, dissolved oxygen rapidly cleaves the resilient carbon-fluorine bonds that make PFAS “forever chemicals” persistent.
Cross-laboratory analysis by ERDC, the Colorado School of Mines, and Eurofins verified that treated liquid effluent met EPA Maximum Contaminant Levels (MCLs) for all regulated PFAS compounds. Chemical oxygen demand (COD) and total organic carbon (TOC) were reduced to near-non-detect levels.
Crucially for plant designers and remediation contractors, direct stack testing via EPA Methods OTM-45 and OTM-50 detected only 0.0005 grams per hour of volatile fluorinated emissions against a system feed rate of 16.6 grams per hour. The report noted that this minimal off-gassing eliminates the capital and operational overhead of secondary gas-scrubbing equipment.
“This is exactly the kind of rigorous, independent validation that the federal market demands,” said Howard Teicher, VP of Government at 374Water. “The U.S. Army put our technology to the test on AFFF under field conditions… That gives federal decision-makers the confidence to move from studying PFAS destruction to actually deploying it.”
The testing was funded under the U.S. Army’s Environmental Quality Technology 6.4 Program. With the Department of Defense actively managing PFAS remediation across hundreds of installations, validated SCWO platforms offer a mobile, decentralized alternative to landfilling or off-site thermal treatment.
Report summary compiled from U.S. Army ERDC Technical Report ERDC TR-26-19 and documentation provided by 374Water Inc.
