A safety assessment of the new Xiangyun phosphogypsum tailings pond

Phosphogypsum tailings are piled up to form a phosphogypsum tailings pond. In the design and operation stages of a tailings project, the stability of the tailings pond, the control capacity for flood, and the reliability of the drainage and safety monitoring facilities should be fully evaluated. Key contents of the safety assessment are analyzed in view of the new Xiangyun phosphogypsum tailings pond, which is currently in the design stage. Flood routing calculation results show that the pond cannot meet the requirements of the China National Standards Safety Code in the condition of a 500-year flood even if the drainage facilities operate normally. Seepage and static stability of the tailings pond are investigated through numerical and limit equilibrium methods. The results indicate that the sliding stability can meet the requirements along the starter dike profile. Dynamic calculation results show that the liquefied area is at the top of the dam slope and it cannot influence the dam safety. The aspects of safety monitoring design that require attention are also proposed.

Graphical abstractMain issues on gypsum tailings safety assessment of Xiangyun new Phosphogypsum tailings pond are studied in this paper.Figure optionsDownload full-size imageDownload as PowerPoint slideHighlights► The numerical method based on strength reduction technique is used to calculate FOS of the tailings dam. ► The generalized multi-peak triangular hydrograph is used to calculate flood hydrograph of the tailings dam. ► The stability of tailings dam, control capacity of flood and safety monitoring are evaluated as a whole.