Groundwater control is commonly used when dry structures or excavations are to be constructed below the groundwater table. These often require a perimeter and bottom cut-off barrier. Perimeter cut-off walls inhibit the movement of contaminants from sites that are polluted. Buried concrete structures, for example tunnels or utility vaults, may need cracks and joints sealed. Specifically dams and levees need to control seepage, so a cut-off wall along the alignment is constructed.
