The March 2017 Feasibility Study completed by Cementation AG (the “2017 Feasibility Study”) outlines a conventional underground mining operation with steady-state production of 2 million tons per annum over a 38-year life of mine.
The mining method selected for the Ochoa deposit is underground room-and-pillar mining with partial pillar extraction. This method was selected for its suitability to mining tabular, strata-bound deposits with low-profile mining equipment.
Polyhalite ore will be extracted via a 1,400ft (450m) vertical shaft from the underground development. Low profile continuous miners (such as the Joy Global 14CM28) with an estimated productivity of 220 tons per hour will excavate polyhalite ore from the underground workings; ore will be transported via a conveyor system to the shaft bottom for extraction to surface.
The 2017 Feasibility study details the mine-extraction methodology and mine plan schedule.
The capital schedule to construct the mine and processing facility is well-defined, totaling $328 million over the course of 4 years (2018 to 2021).