Successful completion of the cut-off wall works for the fourth kimberlite pipe, called A 21, at Diavik Diamond Mine. The mine is located on a 20 square kilometers island in Lac de Gras, approximately 220 kilometers south of the Arctic Circle and 300 kilometers by air northeast of Yellowknife, the capital of Northwest Territories.

Period of Construction: May 2016 – November 2017

In order to construct an open pit mine at A 21, a 2.2 km perimeter dike was constructed and an up to 26 meter deep cut-off wall installed. Bauer convinced the client to apply the Cutter-Soil-Mixing method (CSM), which combines cutter diaphragm walling technologies and the Mixed-in-Place method. The CSM technique is implemented through the use of trench cutters that are specially modified for this process. By utilization the in-situ soils, the CSM technique provides substantial logistic advantages and cost savings compared to methods that are more traditional.