Construction of a vent shaft 5.5m finished diameter and 320m deep. The scope of works includes the manufacture and installation of composite steel and concrete liners to provide full hydrostatic seal with 20 year design life.
Site works include establishing site facilities, survey and setout, construction of shaft collar, pre-sink and drill slab, site clearing and excavation of ponds, and construction of liner preparation area.
An additional 40m depth of the shaft will be steel liner only (bringing the shaft to 360m deep) and the diameter will step in as the steel liners will be drilled and installed after the composite liners are grouted in place. A gap is to be left between the composite and steel liners for mine access to the coal seam.