ABSTRACT
Final closure was proposed for three impoundments containing iron oxide (IOX) at a 500-acre site in the southeastern United States. The closure plan included placing 490,000 cubic yards of additional IOX material within the impoundments, reaching heights 10 to 28 ft on top of the existing embankments. Stability models of the raised impoundment indicated a factor of safety less than required without mitigation measures. Reinforced concrete diaphragm (slurry) walls were proposed as a multi-purpose solution, providing contaminated groundwater cut-off and slope stabilization. Preliminary research indicated that many approaches and solutions were available for pile-stabilized slopes but little design guidance existed for the design of continuous wall-stabilized slopes. The final design used a combined approach aided by the Rocscience products Slide2 (for slope stability) and RSPile (for design of the slope-supporting slurry wall). This paper discusses the approach and methodology adopted for the analysis and design of the slope supporting slurry wall and will conclude with recommendations for further study.
