About the Water & Carbon Group (waterandcarbon.com). The Water & Carbon Group (WCG) is a unique engineering contractor leading the industry in designing, building, and operating multifunctional infrastructure that value natural assets. Operating since 2007, WCG is at the forefront of sustainability services for wastewater, PFAS removal (LEEF System), ecology, and carbon. Product Showcase: LEEF System for PFAS removal (leefsystem.com) We specialise in addressing a critical concern for landfill operators – PFAS contamination in leachate. The Low Energy Evaporative Fractionation (LEEF) System is designed to deliver consistent non-detect PFAS removal in raw leachate streams.