Marathon

The 4,585 ha PGM-Cu project is located 8 km north of Marathon, Ontario, Canada.

It is envisaged as a conventional truck and shovel open pit mining operation that would employ a total fleet of sixteen 228 tonne capacity haul trucks, two 27 m3 diesel-hydraulic shovels, three production drills, a pre-shear drill and one 25 m3 wheel loader, and various ancillary equipment to support the mining operations. The equipment is to be acquired over four years on a lease-purchase plan.

The open pit will operate on a year round basis and provide ore feed to an on-site processing plant and low-grade ore stockpile. The feed rate to the processing plant is designed to be 22,000 tpd ore. The pit will require the removal of a total of 3.6 Mt of overburden and a total of 286.6 Mt of waste rock over a mine life of 10.1 years. The overall waste tonnes to ore tones stripping ratio is estimated to be 3.6:1. The pit design includes inter-ramp pit slope angles that range from 48 to 55 degrees with the majority at 55 degrees.

The waste rock storage facility has been designed to hold the life-of-mine waste rock production and has a storage volume of 114 million m3 with a footprint area of 241 hectares.

The plant design comprises a sulphide flotation facility with a nominal throughput capacity of 22,000 tpd (7.7 M tonnes per annum) based on 90% plant availability. Metallurgical recoveries are estimated at 91% for Cu, 63% for Pt, 77% for Pd, 73% for Au and 77% for Ag.

The process includes primary and secondary crushing using conventional crushers, tertiary crushing using high pressure grinding rolls, ball milling, conventional flotation and concentrate dewatering. Approximately 90,000 tonnes per year of a single bulk concentrate containing copper and high values of PGMs, Au and Ag will be shipped to a third party smelter.

Thickened tailings disposal technology has been selected to minimize the environmental impact of the project. Marathon will dispose of the life-of-mine tailings into a managed tailings facility with a design volume of 49 million m3 and a footprint area of approximately 142 hectares.

The deposit is easily accessible from the Trans Canada Highway and is also close to the CN railway. Electrical power is easily accessible with the deposit being located within 1 km from two spurs of OPG's electrical power grid.