Feasibility Study Solution Mining
AAI recently completed a Feasibility Study in conjunction with SNC Lavalin and Potash One for solution mining the Legacy project located to the south of the KP 289 permit area and where the recent exploration drilling and 3D seismic has confirmed the Measured and Indicated Resource. AAI was responsible for the solution mine plan including designing cavern and pillar sizes, estimating potential subsidence, and refreshing the 43-101 Technical Report (TR) to include identification of mineral reserves. In addition, AAI developed the solution mine plan schedule and capital and operating costs for the solution mine.
Earlier AAI completed NI 43-101 compliant TRs concerning the potash resources contained in the Subsurface Mineral Exploration Permit KP 289 in 2006 and in 2009. The 2009 43-101 TR was revised to incorporate the results of the exploration drilling completed in late 2008 and early 2009. During the exploration drilling program, AAI directed the structural logging and core testing. The most recent 43-101 TR published in mid-2010 in conjunction with the completion of the Feasibility Study identified reserves sufficient to support a 2.85 million tonne per year potash operation for 55 years.
The KP 289 permit area is immediately north of the Mosaic Belle Plaine potash solution mining operation and contains similar quality potash beds as that successfully solution mined by Mosaic and its predecessors for over 30 years.
In addition, Potash One commissioned AAI to analyze subsidence potential from planned solution mining of three potash beds at the Legacy project site. Long-term predictive subsidence was analyzed for 40- and 100-year mine plans using the influence function method during primary and secondary mining. Hundreds of underground caverns were analyzed for subsidence potential at the Legacy project site.