Features of the strain development in phosphogypsum dumps

The results of long-term geodetic observations in the formation of phosphogypsum dump of the Balakovo branch JSC "Apatit" in the Saratov region, which allowed studying the regularities of development of deformation processes due to the simultaneous occurrence of landslide displacements and settlements of the dump’s surface, are presented. The causes, mechanism, dynamics and conditions of formation of landslides on the phosphogypsum dump, including the impact of the technogenic aquifer on the bearing capacity of the structure base changing, are discussed. Laboratory studies of phosphogypsum describe its as a highly compressible material with marked rheological properties. This fact determines the development of the large settlements of phosphogypsum dumps continuous in time. Presented knowledge in this work can be useful in assessing the sustainability of phosphogypsum dumps and the determination of their maximum capacity.