Engineering services in this class for building project development services; scaffolding; installation, maintenance, and decommissioning of underground mining equipment and plant including crushing stations, truck loading systems, headframes, winders, shaft conveyances, paste plants, grizzly and ore pass systems, portals, dewatering equipment, pumping systems, ventilation systems including ventilation doors, escape ladders, refuelling bays and deluge systems, explosive magazines, paste reticulation piping, rising mains, and refuge chambers; installation, maintenance, and decommissioning of mill and crusher foundations, suspended slabs, marine infrastructure, tilt panels, retaining walls, sumps and loading ramps, bunded slabs and aprons, and camp infrastructure