Patent ID: 8585319

Claim:
A structure for disposing of methane beneath the ground, comprising: (i) a subsoil biofilter layer which receives methane, the biofilter layer containing biofilter material for converting the methane to carbon dioxide and water, and comprising structural portions which prevent crushing of the biofilter material and are pervious to gas to permit gas to pass into and out of the biofilter layer, wherein the structural portions of the biofilter layer are provided by a first horizontal array of prefabricated units which have upwardly extending portions to resist compression and have apertured walls to permit gas flow, the walls of each prefabricated unit defining an interior which contains the biofilter material; (ii) a subsoil ventilation layer above the biofilter layer, into which the carbon dioxide from the biofilter layer passes and is diluted with air, the ventilation layer comprising structural portions which define a ventilation space and are pervious to gas to permit gas to pass into the ventilation space from the biofilter layer, wherein the structural portions of the ventilation layer are provided by a second horizontal array of prefabricated units which have upwardly extending portions to resist compression and have apertured walls to permit gas flow, the walls of each prefabricated unit defining an interior which defines part of the ventilation space; and (iii) a first vent communicating with the ventilation space to vent the diluted carbon dioxide to the atmosphere.