Abstract: Means and methods employing gas-solid heterogenous photocatalysis ("GSHP") to counteract the widespread occurrence of groundwater and air polluted by volatile organic compounds (VOCs) such as trichloroethylene (TCE) and non-volatile organic compounds such as polychlorinated biphenyls (PCBs), and the like without creating other environmentally hostile agents. Common treatment methods such as spray tower aeration and activated carbon adsorption, both of which merely convert pollutants into alternate but equally obnoxious forms, can be augmented by the means and methods hereof to create ecologically innocuous byproducts. Heterogeneous photocatalysis allows the complete destruction of those organic water pollutants normally contained in the effluents of existing water treatment facilities. Ambient temperature ultraviolet-illuminated catalyst, such as, titanium dioxide, in the presence of moist air substantially completely destroys trichloroethylene (TCE) type-materials in a gaseous phase.