The paper is devoted to the solidification of radioactive sea-salt concentrates in a modular cementing facility yielding 200-liter cement blocks. The solidified products with Cambrian clay added as a sorption aid satisfy with respect to the mechanical strength and radionuclide leaching the domestic and foreign requirements for safe storage in standard and very simple disposal sites.Liquid radioactive wastes which often contain sea salts in substantial amounts are formed during the operation of propulsion nuclear power systems (NPSs). Floating facilities for reprocessing radioactive waters (the special tankers Amur in the Northern fleet and Pinega in the Pacific Ocean Fleet) were provided for reprocessing radioactive water. The plan was to incorporate the radioactive concentrates into bitumen compounds using the proposed technology [1]. However, because the bituminization process presents a danger of fire and explosion and the solidified products are plastic and combustible (the flash point is below 300°C) it is being replaced by the technologically simpler, safer, and less energy intensive cementing process.Cementing for solidifying radioactive concentrates by simple mixing of the components makes it possible to obtain strong and noncombustible products which retain their integrity even in shipping accidents. For example, cement blocks do not lose their shape after standing for 30 min at 800°C, and since their mechanical strength is 10 MPa they remain whole when dropped from a height of 9 m [2]. However, cement compounds do not fix radionuclides nearly as strongly as bitumen compounds.Sodium chloride (NaCl), which determines the salt content of sea waters, does not interact chemically with bitumen.