The Waterloo Emitter™ is designed to assist in-situ remedial biodegradation of MTBE, BTEX and other contaminants. It enables oxygen (or hydrogen for anaerobic remediation) to diffuse through silicone or LDPE tubing in a controlled uniform manner. The simple, low-cost, patented technology consists of a PVC frame wrapped with tubing that can be pressurized to obtain the desired diffusive transfer of gas, appropriate to site-specific needs. Sized for 2", 4" and 6" (50, 100 and 150 mm) wells, the units can be stacked in a well and joined from one well to another, to allow the controlled continuous diffusion of gas into the plume.