[en] Multigroup cross-section libraries have been prepared for the thermal power reactor code EPRI-CELL using the NJOY nuclear data processing system and ENDF/B-V evaluated nuclear data. Various combinations of scattering matrices, absorption and/or fission cross section, and self-shielding factors are included for the major fissile, fertile, fission product, structural, and moderator materials used in modern light water, heavy water, and graphite reactors. An extensive new set of actinide and fission product buildup and depletion chains is included. The processing methods and changes made to the codes EPRI-CELL, LIBRAR, GAMTAP, and BLIB in order to use the ENDF/B-V cross sections effectively are also described