Abstract: A subsoil methane collection and treatment system (10), which includes a subsoil distribution layer (13) for receiving methane, a subsoil biofilter layer (14) above the distribution layer which contains a biofilter (18) such as compost to convert the methane to carbon dioxide and water, a subsoil ventilation layer (15) above the biofilter layer, in which the carbon dioxide is diluted with air, and a vent (17) to the atmosphere from the ventilation area for venting the diluted carbon dioxide. The layers may be defined by horizontal arrays of load bearing prefabricated structural modules (1). The system (10) may collect methane from the ground beneath and/or be fed with methane collected from beneath a building (19) adjacent the system.

Abstract: A subsoil methane collection and treatment system (10), which includes a subsoil distribution layer (13) for receiving methane, a subsoil biofilter layer (14) above the distribution layer which contains a biofilter (18) such as compost to convert the methane to carbon dioxide and water, a subsoil ventilation layer (15) above the biofilter layer, in which the carbon dioxide is diluted with air, and a vent (17) to the atmosphere from the ventilation area for venting the diluted carbon dioxide. The layers may be defined by horizontal arrays of load bearing prefabricated structural modules (1). The system (10) may collect methane from the ground beneath and/or be fed with methane collected from beneath a building (19) adjacent the system.