Red mud reservoir, cavity 2, belonging to Nhan Co Alumin factory complex located in Dak Rlap district, Dak Nong province, was completed in 2015, during operation because waste storage has not been implemented (backup reservoir), so there was a landslide phenomenon with a length of about 335m. The research and treatment of underground water level on the roof of the lake in different operating cases of the lake is not really thorough, making this area unstable and becoming more complicated after each rainy season. Design solutions to drain surface water, groundwater, protect HDPE roofs, filter structures to collect groundwater, etc. have been proposed. The article summarizes the main developments in the research and treatment of lake slope erosion and evaluates the effectiveness of the solutions that have been studied and applied.