[en] The Institute for Energetic and Nuclear Research, working on environmental applications, has an extensive research programme using high energy electron beam in treating industrial wastewater and sludge. The experiments are being conducted in a pilot plant using an industrial electron beam 1.5MeV, 25mA, where the streams are presented to the scanned electron beam in counter flow. This pilot plant is designed to process approximately 3.0m³/h with an average dose 5kGy and the absorbed dose measurement is performed continuously by calorimetric system in real time. Combined biological and radiation treatment of domestic sewage and sludge were carried out to investigate disinfestation and removal of organic matter. The experiments showed that total and fecal coliforms were decreased by about 5 logs cycles with a 3.0kGy radiation dose in raw sewage and biological effluents, respectively. Concerning the industrial wastewater in the first stage of the programme, the irradiation was conducted using batch systems with samples originating from a Governmental Wastewater Treatment Plant. The data showed a significant color reduction effect when delivered dose was increased, and the opposite was noted for turbidity and total suspended solids. Other experiments were focused to process real industrial effluents from one of the most important chemical and pharmaceutical industries in Brazil. A special transport truck was used to transfer the liquid waste from the Industry to the Electron Beam Pilot Plant. Large quantities of liquid waste were irradiated with and without air addition with the doses from 2kGy to 20kGy. Such experiences performed in association with the Industry demonstrated that this technology has a great potential to be transferred and to contribute with a permanent cleanup alternative for hazardous wastes