Within the reconversion activities of the industrial complex of S. Enfemia Lamezia (Ct, Italy) into an environmental service plant system, a vegetation water treatment plant was started in November 1995 suitable to treat a nominal capacity of 300 m(3)/d flowing from olive-oil mills. The treatment plant is based on the following steps: 1) Dirty water storage, 2) oil removal system, 3) Settling of suspended solids, 4) Tangential filtration on polymeric membrane, 5) Eluate treatment by means of polymeric membranes in a double-step biological process complying with Italian standards. The finaI reconversion of the industrial complex into an environmental service plant system will be composed of a sewage treatment line, an oil vegetation treatment line, a solid waste incineration line, and a compost solid waste line.