Aiming at the problem of radioactive waste disposal, the concept and mechanism of self-burial by deep rock melting are presented. The rationality and feasibility of self-burial by deep rock melting are analyzed by comparing with deep geological burial. The heat threshold during the process of contact melting around a spherical heat source is defined. The descent velocities and burial depths of spherical waste containers with varying radius are calculated. The calculated depth is much smaller than that obtained in the related literature. The scheme is compared with the deep geological burial that is currently carried out by the main nuclear countries. It is found that, at the end of melting, a radioactive waste container can reach deep strata that are isolated from groundwater. 1. Introduction According to the latest report from the OECD/NEA [1], nuclear energy will be the only choice to replace the carbon fuels and satisfy the global energy needs. However, for nuclear energy, the problem of radioactive waste disposal is inevitable. The problem has existed for more than half a century since the development of the first nuclear power plant. There are available deep geological disposal solutions in France, Sweden, Finland, or USA, but at the moment there is no operating facility available for radioactive waste from civil use of nuclear energy. In 2020 also first disposal operating facility is expected in Finland. At the present time, most of the waste has to be stored temporarily, and the long-term storage has been proven to be safe and efficient. A lot of countries are in process of long-term storage prolongation from 50 to 100 years [1]. The peculiarity and difficulty with the disposal of spent nuclear fuel (SNF) lie in its high radioactivity and longevity. The most popular schemes being researched for waste disposal are the transmutation and the deep geological burial [1]. The transmutation is a type of nuclear reaction, in which a long-life radioactive nuclide is changed into a steady-state or short-lived nuclide so that the amount of radioactive waste is much reduced and its disposal is much simplified. The significance of transmutation also lies in its efficient use of valuable nuclear resources such as 238U and 232Th. However, research on the transmutation has not advanced beyond its earliest stages because of its complexity so that the future of this technology is still unclear. Deep geological burial is one of the most popular schemes at present. In this scheme, the spent fuel should be vitrified and compacted first and then is put into a special
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