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The EURISOL (The EURopean Isotope Separation On-Line Radioactive Ion Beam) project aims at designing a facility for producing high intensity radioactive ion beams, with unprecedented (two to three orders of magnitude higher) intensities, compared to the majority of the worldwide existing RIB facilities. For this purpose, a proton beam of energy 1 GeV and intensity up to 4 mA impinges on a liquid mercury target (the converter). The high neutron fluxes (in excess of 1015 n cm-2 s-1) produced by spallation nuclear reactions in the converter induce fission on 235U targets surrounding the liquid mercury converter. In order to attain the intended high intensity radioactive ion beams, the appropriate configuration (geometry and materials) of the target unit components (converter, fission targets, moderators, reflectors) must be determined, to attain the highest possible fission rates in the uranium targets (in excess of 1015 fissions per second). The extremely high neutron and photon fluxes resulting from the operation of the target unit impose, for radiological protection and safety purposes, a careful assessment of the dose rates in the surrounding areas. Activation of the structural components must be studied. Thick shielding barriers must be designed. In this work, the so-called MAFF inspired target configuration, allowing a versatile operation, maintenance, remote control and storage of the fission targets is considered. The results obtained using the state-of-the-art Monte Carlo codes MCNPX and FLUKA are presented. The neutronics, dose rate, shielding and activation calculations, needed for radiological protection and safety assessment purposes are discussed. [ABSTRACT FROM AUTHOR]