FIELD: treatment of highly active waste; solidification of wastes by their immobilization in ceramic block. SUBSTANCE: method for solidifying concentrate of transplutonium and rare-earth elements in synthetic monazite involves deposition of orthophosphates of transplutonium and rare-earth elements from their concentrates, addition of concentrated solution of lead nitrate to deposited orthophosphates, calcination of blend obtained, and compacting of calcine by hot pressing. Ceramic block is obtained at lower pressing temperature than in known method without impairing its most important characteristics, namely, apparent density, open porosity, and rate of radionuclide leaching. EFFECT: improved temperature conditions. 1 tbl
