Overview
The Kidd Mine is in northern Ontario, 500 miles northwest of Toronto. The mine began operation in 1966, producing copper, zinc, indium, cadmium, silver and sulphuric acid. The deposit is one of the largest and richest volcanogenic massive sulphide deposits in the world.
There is an underground mine, and metallurgical facilities consisting of a copper concentrator, smelter and refinery, and zinc, cadmium, indium plant, liquid sulphur dioxide and sulfuric acid plant. Kidd's concentrating, smelting and refining processes are among the most advanced in the world.
The mine currently employs 1400 people and operates 7 days a week with two 12-hour shifts. The properties comprise 14 patented half lots covering 896 hectares of freehold mining land.
Commissioning for Mine D expansion began in 2004, and is scheduled to increase the operation's ultimate capacity, in stages, to 2.7Mt/yr of ore to 2012 and deepen Kidd Mine to a final depth of 9,500 ft and extending the life of mine to 2017. Kidd is the deepest base metal mine in the world.
Location
The mine is located 22 kilometres north of Timmins and is the largest employer in the area. Mine tours are offered in July and August.
From the U.S. the closest border crossings are at Sault Ste. Marie, Michigan, Detroit, Michigan and Buffalo, New York (Niagara Falls). By road from Sault Ste Marie, travel north on Highway 17 to Wawa then east on Hwy 101 to Timmins.
Geology and Mineralization
The Kidd orebody consists of three main massive sulphide lenses (north, south and central orebodies) each underlain by it's own hydrothermal plumbing system of copper stringer material.
Several structures control boundaries of ore lenses. Between the 68 and 82 levels, sub-vertical rhyolite "south dippers" contact and plunge NW of massive sulphide, possibly due to poorly defined S-dipping fault. Below the 88 level shallow dip of rhyolite 'north dippers' massive sulphides is likely due to a north-dipping fault that defines contact and is a cause of difficulties in deep drilling below the 90 level. An east-west shear type sharply separates the main lens from the south and greywacke lenses.
Mining Operation
The mining method underground is blasthole stoping. Key equipment underground includes Ingersoll-Rand, Cubex and Mission blasthole drills, Tamrock haulers. Ore on the 6000 level passes through a rockbreaker and grizzly , crushed by a 360 M.T.P.H. jaw crusher. Phase 2 development calls for a second gyratory crusher capable of crushing 1.2 million tonnes per year at the 6800 level. Ore is skipped to the surface.
Production drilling is done with a fleet of 9 In-the-hole hammer drills. A 1.2 m or a .7 m bored slot raise is drilled from the sublevel to the undercut using a Robbins 34R raiseborer. The slot is opened up by blasting around the raisebore hole in stages. Rings which are typically spaced at 3 meters can then be blasted into the slot.
Ore is crushed by a 42x 65 gyratory crusher on the 2800 level, skipped to the surface, and hauled by rail 27 kilometers to the metallurgical site at Hoyle. The train uses twenty-five to thirty 90-tonne rail cars and makes 4 to 5 trips per day.
Processing
Processing facilities (Kidd Metallurgical) are located 27 kilometres southeast of the mine site and consist of a concentrator, a zinc plant, a cadmium plant, an indium plant and a sulphuric acid plant. The concentrator crushes and grinds the ore before flotation.
The mill produces copper and zinc concentrates, and treats all ore from the Kidd Mining Division in two of the four circuits.
The zinc plant has the capacity to produce 150,000 tonnes per year. Zinc concentrates are roasted and the sulfur oxides and trioxides are sent to the sulphuric acid plant. Zinc calcine is leached and cadmium is extracted. The purified zinc-rich solution is sent to the electrolysis plant where zinc is plated onto aluminium cathodes. Indium, zinc and copper are recovered from the indium plant.
The plant processes ore from other mines in order to run at full capacity.
Environment and Community
The main focus of the Environmental section is to treat the water that is discharged from the mine property so it can go back into the environment. This involves treatment with lime, residence in a settling pond, pH control with CO2 prior to discharge, and regular sampling throughout the process. Regular reports are made to the Ministry of Environment & Energy.
Over 100 million tonnes of base metal sulphide tailings are thickened in the tailings pond. By the time the site closes in 2023 more than 130 million tonnes will be stored. The radius of the conical pile is 1.2 km and the height of the cone is 25 m. The cone will grow by 0.2 m/y and by closure is expected to be 29 m high.
