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Western Exposure LLC. <br />Environmental Consultants <br />3291 East 500 North - Lewisville - Idaho 83431 <br />Cindy Gilbert 208 - 390 -9428 <br />cindygilbert140@gmail.com <br />Exhibit A <br />MEMORANDUM TO: Randy McClure — Rio Grande Silver, Inc. <br />COPIES TO: Cindy Moore, Paul Glader - Hecla Mining Company <br />FROM: Cindy Gilbert <br />SUBJECT: Preliminary Bulldog Waste Rock Characterization <br />Background <br />March 25, 2013 <br />At the request of Rio Grande Silver, Inc. (RGS), Western Exposure conducted a Bulldog Project <br />site inspection on the afternoon of March 7, 2013. The purpose of the visit was to observe the <br />current conditions of the historic Bulldog Mine Waste Rock Storage Facility (WRSF) and <br />determine if obvious downstream impacts have occurred as a result of past mining activities. <br />Homestake Mining Company (HMC) operated the Bulldog Mine from 1965 through 1985 when it <br />closed due to depressed metals prices. HMC accessed the underground workings via an <br />incline (+1%) which was excavated in two primary rock units; the Creede and Campbell <br />Mountain formations. Material from the incline was placed on the surface for permanent <br />disposal. The development waste rock removed and placed on the surface from the 20 years of <br />operation was comprised primarily of Campbell Mountain Formation, which is the host rock for <br />the mineralized veins. From 1994 to 2007, HMC removed the majority of the surface <br />infrastructure and reclaimed the WRSF. Reclamation consisted of regrading with a slope <br />sufficient to encourage surface runoff, placement of approximately 8 -12 inches of growth <br />medium, and revegetating with an approved seed mixture, consisting of Slender Wheatgrass, <br />Mountain Brome and Streambank Wheatgrass. The reclaimed Bulldog WRSF encompasses <br />roughly 17 acres. <br />RGS is currently conducting exploration activities at the Bulldog, which currently includes <br />excavating a 14 -ft wide by 14 -ft high by roughly 2800 -ft long decline ( -1 %) to access the historic <br />workings to further advance the exploration program. The decline will intercept the same two <br />primary rock units as the historic incline. Of the 2800 -ft total decline length, the Creede <br />Formation will account for 1700 feet, or roughly 60 %, of the material removed and stockpiled on <br />the surface. The remaining material placed on the new WRSF will be from the Campbell <br />Mountain Formation. Figure 1 depicts the current decline and historic incline alignments in plan <br />view, along with a cross - section portraying the decline alignment with anticipated geologic <br />formations to be intercepted. <br />