"Landfill" means any location operated as a commercial venture for profit or operated by a county or municipality for the disposal of solid wastes or any location where a private owner accepts solid wastes for compensation from sources other than his own [...]

(14) "Landfill" means an area of land on which or an excavation in which solid waste is placed for permanent disposal and which is not a land application unit, surface impoundment, injection well, or compost pile.