The Pumpkin Hollow Project load haul dump (LHD), also known as a scoop tram, and a jumbo drill were hoisted down the shaft and put to work last week.
The 25,000 lb. LHD truck is a specialized loader manufactured for underground mining. LHDs are used to load or scoop blasted mine waste rock and ore (known as ‘muck’ in the mining business), into the bucket, and haul it to an ore or waste pass or primary crusher before being hoisted to the surface.
Nevada Copper will be using the LHD to load muck from the lateral drifts (tunnels) under construction and transport it to the shaft. The muck is then hoisted 1,900 feet up the shaft in buckets to the surface and then placed in a permanent mine rock storage area. The drifts will initially be used to access underground drill stations to further define and expand the boundaries of the mineral deposit. As the mine develops they will be used to access mining areas. The drifts are 16 feet high by 16 feet wide, designed to eventually accommodate 30-ton underground haul trucks.
Prior to hauling the muck, the Drill Jumbo drills blast holes in the rock which are filled with explosives and then blasted. A scissor-lift truck has also been lowered down the shaft and will be used to bring down loose material after the blast to make the drift safe. It will also be used to install the rock bolts and steel mesh that help reinforce the drift’s back (ceiling) and ribs (sidewalls), and to spray shotcrete and other operations.