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Interim Waste Rock Characterization Summary— Bulldog Mine <br /> December 15, 2014 <br /> From September 2012 through August 2013, Rio Grande Silver, Inc. (RGS)excavated a decline from the <br /> surface to intercept the historic Bulldog Mine workings for the purpose of completing an underground <br /> exploration program. The program was designed to increase knowledge and verify known resources as <br /> well as drill and explore for new resources. Although the decline was completed as planned,the <br /> underground exploration program was put on hold due to low metals prices. <br /> Material removed during the decline excavation was placed in a surface Waste Rock Storage Facility <br /> (WRSF). Representative samples of material placed on the surface were gathered during the excavation <br /> and were submitted for waste rock characterization testing. Results of tests completed to date are <br /> presented in this summary report. <br /> Background <br /> The 1860-ft long decline was excavated 14-ft wide by 14-ft high with an arched back. Two wide spots <br /> were developed at 500 ft intervals from the portal to accommodate passing zones,temporary muck <br /> (material)storage, and equipment and infrastructure placement. These wide areas were excavated 100- <br /> ft in length and 20-ft wide. <br /> Two rock units were intercepted while excavating the decline;the Creede Formation (TC) and the <br /> Bachelor Caldera Sequence,Willow Creek Member(TBW). The highly variable Creede Formation <br /> consists of fine-to coarse-grained sandstones and conglomerates with minor amounts of talus breccia, <br /> thinly-bedded lacustrine tuffs and tuff breccias. Mineralogy of the Creede Formation is dominated by <br /> quartz(>72%)with minor amounts of feldspar and accessory minerals. The Willow Creek Member <br /> consists of rhyolitic and rhyodacitic ash flow tuff and air fall tuff volcanic outfall facies. Mineralogy of <br /> the Willow Creek Member contains primarily quartz (>74%)with minor amounts of feldspar and <br /> accessory minerals. Refer to the Whole Rock Geochemistry table below for additional information. <br /> Accounting for a typical 14-ft by 14-ft decline profile, along with wide zones,approximately 13,800 cubic <br /> yards of material (estimated 77%of material from the Creede Formation and 23%from the Willow <br /> Creek Member)was placed in the WRSF. Shotcrete was used in the decline development to support the <br /> ground as a safety measure. A two(2) inch "flash coat" of reinforced shotcrete was applied on the back, <br /> ribs(walls)and face after each five(5)foot advance,followed by installation of steel lattice girders and a <br /> final four(4) inch coat of reinforced shotcrete on the back and walls. With each 5-foot advance, a <br /> certain amount of the in-place shotcrete, by design,was compromised by the blast and removed with <br /> the waste rock. This process added shotcrete at an estimated 3.3%by volume while advancing in the <br /> Creede Formation and 2.8%by volume while advancing in the Willow Creek Member accounting for an <br /> estimated 400 cubic yards of shotcrete in the WRSF. <br /> As the majority of the decline was excavated in the Creede Formation, and due to its highly variable and <br /> heterogeneous nature,two samples were taken from the Creede Formation rock unit for <br /> characterization. One sample was taken at the Portal+380 foot mark and another at the Portal+1391 <br /> foot mark. In contrast, due to the more homogenous nature of the Willow Creek Member,only one <br /> sample was taken for characterization. The three samples were analyzed separately, both as a <br /> composite and with shotcrete, in order to best approximate the WRSF configuration. Compositing <br /> techniques are further described below. <br /> 1 <br />