The Martha project was the first major hard rock mining operation to be commissioned following the resurgence of the gold mining industry in New Zealand in the late 1970s. The Martha Mine is situated in the Waihi township, and the processing plant, waste rock embankments, water treatment plant and Favona Mine are located two kilometres away in a rural area. Because of its location, Waihi mining operations have received a high level of public scrutiny. This is reflected by the stringent conditions set for the projects.
Martha open pit
Mining at Martha is by open pit methods. Ore and waste rock are crushed at the surface facilities area prior to transportation along a 2.7 kilometre conveyor. On arrival at the processing plant gold and silver are extracted from the ore using conventional carbon-in-pulp treatment methods. Waste rock is used to construct an engineered earth embankment to contain the tailings. A water treatment plant treats excess water prior to discharge. Mining within the open pit is currently focussed on laying back the eastern wall, a project that will see mining activity continue until 2014.