This paper presents a scientifically substantiated and experimentally validated study of the structure formation patterns of a polychelate composite based on a polymer matrix and enrichment waste used as a filler. It was established that cyclic cryogenic exposure ensures the formation of a heterogeneous, highly filled system with developed interphase zones. Using powder X-ray diffraction, basal reflections of layered hydrosilicates (muscovite-2M1 and kaolinite-2M) were recorded against a pronounced amorphous halo of the polymer matrix, demonstrating the chemisorption process without disrupting the crystalline structure of the filler. The observed polymorphic transformation of feldspars, with the transition of sanidine and microcline to orthoclase, indicates deep relaxation of internal microstresses in defective near-surface layers at the phase boundary. This process occurs due to the formation of coordination bonds between the functional groups of the matrix and the metal cations of the filler, which is confirmed by the high-frequency shift of the stretching vibrations of carboxylate anions in the infrared spectrum. The method of computed X-ray microtomography revealed the formation of a continuous spatial framework, the dominance of pores with sizes of 15-45 μm and the presence of a large number of isolated micropores with an average size of 13 μm. The spatial organomineral structure formed during cryogenic treatment is characterized by a low thermal conductivity coefficient (0.18 W/(m⋅K)) and the maximum water resistance grade (W20). The method of biotesting on test objects of two trophic levels proved the environmental safety of the developed material: the mortality rates of Daphnia magna Straus were 3.8–7.0%, deviations in the number of Chlorella vulgaris Beijer cells were 1.6-17.4%. The high efficiency of chemisorption immobilization of toxic components in the composite structure eliminates the risks of their desorption and leaching, which allows it to be recommended for reliable hydro- and thermal insulation of tailings storage facilities in cryolithozone conditions.