Case Study: Portable PFAS Water Treatment Skid 

Challenge: Provide a water treatment system to remove PFOS, PFOA, and PFBA from multiple wells at a firefighting training site.

Perfluoroalkyl and polyfluoroalkyl substances (PFAS) are a class of man-made chemicals suspected to cause adverse human and ecological health effects.  Many sites across the US have been accumulating these compounds from fire fighting foam and/or manufacturing waste/landfill operations. PFAS compounds have unique physical and chemical properties that render them highly stable and resistant to degradation in the environment and must be removed from drinking water sources before they are allowed to accumulate in living organisms with adverse health effects.

Solution: A packaged carbon filter skid provides portable PFAS treatment, capable of pickup truck transfer between sites.

In October of 2024, H2K Technologies constructed a Liquid Phase Granular Activated Carbon adsorption pilot system for use at former firefighting training areas at a major airport. This system tested treatment effectiveness for removal of PFAS contaminants from multiple water wells. The pilot LGAC system consisted of (2) H2K LCF-001 vessels each with 90 lbs of Calgon F-400 bituminous granular activated carbon along with feed pump and bag filtration on a steel skid. system to allow transport between testing sites.  The system produces treated water containing nondetectable levels (<2 ppt) of PFAS compounds when the concentration of PFAS in the raw water is up to 1.0 µg/L, at flows up to 5 gpm. This project site had multiple wells impacted by PFAS, so this system was packaged on a compact skid capable of transport in a pickup bed.

This pilot scale treatment system is serving to provide field tests and feedback for a larger permanent water treatment system.  Installation of the full-scale system is planned for 2026, it will include (2) 2,000 lb LGAC vessels along with (2) 40 ft^3 PFOS selective resin contactors as a polish in an enclosure with HVAC/controls to handle 50 gpm. Multiple media are used in this process to effectively treat a wide range of PFAS compounds. The short chain PFBA compound is usually the highest concentrated compound in fire fighting foam. Carbon vessels perform well for long-chain compounds like PFOA and PFOS, and ion exchange vessels are commonly required to treat short-chain compounds like PFBA.  Activated clay was also considered for PFOS treatment and may be installed in the future. The resin will be tested along with the LGAC to determine the extended bed life capable between changeouts.