Custom Tank Designs That Actively Manage PFAS Mass Transfer Zone (MTZ) — And Why It Matters More Than Ever

As utilities prepare for the pending 4-ppt PFAS drinking water MCL, many are discovering that legacy lead/lag designs—workhorses for decades when treating contaminants in the ppm and ppb range—simply are not optimized for the parts per trillion-level (ppt) precision PFAS demands. The challenge is not just about removing PFAS; it is about managing the Mass Transfer Zone (MTZ) with far greater control than traditional “cookie-cutter” treatment skids were ever built to provide.

Sentinel Water Solutions has approached the problem from a different angle: custom-engineered treatment skids built around hydraulic loading rate (HLR), flow variability, empty bed contact time (EBCT), and the unique behavior of PFAS breakthrough curves. By designing systems around the way PFAS actually behaves—not around a fixed skid footprint—we enable utilities to optimize MTZ progression, maximize media utilization, and reduce total cost of ownership.