To facilitate the expansion of mining operations, the owner required a suitable storage reservoir to relocate 250 megalitres of water. The most efficient and economical solution was to increase the water level of an existing reservoir. In order to do so, Menard Oceania was awarded the installation of a bentonite slurry cut-off wall in the poor quality soils around the perimeter of the reservoir. This cut-off wall was designed to prevent the flow of water through these soils when the water level was increased in the reservoir.
The reservoir was a previously excavated open pit coal mine. The cut-off wall was installed in the surrounding material which consisted of overburden excavated from the pit and deposited on the pit perimeter.
During a 5 weeks period 5,186 m² of bentonite slurry cut-off wall was installed over 600 linear metres. The max depth excavated using the long reach excavator was 14 m.