NOVELTY - Contaminant is removed from a matrix comprising soil, a vadose zone, and/or a saturated zone by injecting an oxygen containing gas through a non-vertically disposed injection well passing through the matrix, extracting the gas from the matrix through a vertically disposed extraction well, treating the gas to remove harmful products, and ejecting the contaminant depleted gas into the atmosphere.    USE - The invention is used to remove contaminant from a matrix comprising soil, a vadose zone, and/or a saturated zone.    ADVANTAGE - The invention is more efficient and economical than known methods. It also combines all of the advantages of known methods into one mobile treatment system. It also enhances the effectiveness of all methods contained in the mobile treatment system through the accompanying injection of heat and pure oxygen. It also delivers the decontamination inputs from the treatment system in such a way as to impact much more of the contamination plumes than known methods.    DETAILED DESCRIPTION - Removal of contaminant from a matrix comprising soil, a vadose zone, and/or a saturated zone, involves :    (a) injecting an oxygen containing gas through directionally, non-vertically disposed injection well(s) (31, 33) passing through the matrix. The injection well has a porous wall to enable the injection of the gas under positive pressure from the well into the matrix;    (b) extracting the gas from the matrix through generally vertically disposed extraction well(s) (35). The extraction well is under negative pressure and has a porous wall to enable the extraction of gas from the matrix into the extraction well. The injection well is disposed below the contaminant material in the matrix. The wells are disposed such that the zone through which the gas passes in the matrix between the wells contains the contaminant material to allow the oxygen containing gas to accelerate the formation of gaseous or vaporized contaminant products that are carried along with the gas;    (c) treating the gas after extraction to remove the harmful products in the gas that were derived from the contaminated material; and    (d) ejecting the contaminant depleted gas into the ambient atmosphere.    An INDEPENDENT CLAIM is also included for an apparatus for carrying out the invented method, including directionally, non-vertically disposed injection well(s) with a porous wall; a positive pressurization apparatus; generally vertically disposed extraction well(s) with a porous wall; a negative pressurization apparatus; and a treating apparatus, and a conduit.    DESCRIPTION OF DRAWING(S) - The figure is a flow sheet and schematic diagram illustrating the invention.    Injection wells (31, 33)    Extraction wells (35)