Subsequent to announcing the results of the Milestone PEA, Western Potash reported on July 6 that Beijing Tairui Innovation Capital Management Ltd. had agreed to acquire a 51% interest in Western Potash through purchase of shares valued at about C$80 million. Proceeds from the investment will be used to develop the Milestone pilotscale operation. The transaction was expected to close by the end of August.

The 2012 Milestone feasibility study had considered a project producing 2.8 million mt/y of KCl. Capital costs to develop such a project were estimated at C$2.91 billion. Operating costs were estimated at C$62.28/mt at full production capacity.

The pilot-scale PEA envisions simultaneous operation of three pilot production caverns. Horizontally drilled wells will inject a NaCl-saturated brine into the potash formation at a temperature higher than the insitu rock formation temperatures. KCl will be selectively dissolved, leaving behind a lattice of NaCl. The KCl-rich brines will be pumped through production wells to a surface crystallization facility.

The PEA is based on a measured resource of 7.17 million mt grading 39.5% KCl, an indicated resource of 11.56 million mt grading 39% KCl, and an inferred resource of 1.77 million mt grading 39% KCl. A cutoff grade of 15.8% KCl was used to define the top and bottom of the target resource.