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The results of calculations of a high-capacity subcritical molten-salt reactor burning transplutonium elements and operating with a fast-intermediate neutron spectrum and the salt LiF-NaF-KF are presented.It is shown that this reactor makes it possible to burn ~300 kg/GW of americium per year, i.e., long-lived wastes from approximately 30 VVER-1000.To develop nuclear power and ensure its competitiveness with conventional and new power directions it is necessary to solve the problem of handling spent nuclear fuel, first and foremost, the long-lived radioactive wastes, specifically, the transplutonium actinides americium and curium. The two main concepts for utilizing them -storage or burning together with other actinides Pu, Np, and U in recycled fuel for fast reactors -have not yet reached technological maturity [1]. The OMEGA program [2] presumes that they are utilized in specialized reactors, preferably with minimal use of fissile materials, specifically, plutonium [3]. The choice of a specialized reactor remains a subject of discussion, and the molten salt reactor is a candidate. The advantage of a fast neutron spectrum for such a reactor has now been recognized [3]. Attempts to secure a fast neutron spectrum by using chloride salts have been unsuccessful because of their high corrosiveness, so that modern designs of molten salt reactors are based mainly on fluoride salts.Fluoride salts, unlike chloride salts, are compatible with construction materials, but to increase the fast-neutron fraction in their spectrum the solubility of actinides must be increased. Fuel salt with high solubility of plutonium and americium fluorides was unknown until recently, and for this reason data showing their high solubility in the eutectic LiF-NaF-KF [4] are critical (Fig. 1). These results were placed at the basis of the concept of subcritical molten-salt reactor for incinerating transuranium elements. The subcritical operating regime is due to the low fraction of delayed neutrons in the fission of 239 Pu (β = 0.22%), 238 Pu (β = 0.14%), 241 Am (β = 0.14%), and 245 Cm (β = 0.18%).The basic scheme of a conventional reactor for subcritical systems includes a target assembly, consisting of a channel for introducing a proton beam and neutron-generating target and surrounded by a subcritical molten-salt blanket where transplutonium elements are burned (Figs. 2, 3 and Table 1). The transmutation zone is surrounded by the first cooling loop, which includes the circulation pumps and heat exchanger, in which the same salt as in the reaction zone LiF-NaF-KF is used

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