2014-12-29_REPORT - M1977215

• Permit No: M1977215
• IBM Index Class Name: Report
• Doc Date: 12/29/2014
• Doc Name: Interim Waste Rock Characterization Summary, 1.
• From: Rio Grande Silver, Inc.
• To: DRMS
• Email Name: RCO
• Media Type: D
• Archive: No

Lead 0.019 0.18 0.17 0.22 0.25 0.15 0.13 0.12 0.077
Lithium <0.10 <0.10 <0.10 <0.10 <0.10 <0.10 <0.10 <0.10 <0.10
Magnesium 6.5 4.7 2.6 2.0 1.7 1.3 1.0 1.0 0.79
Manganese 2.7 2.7 1.5 1.3 1.0 0.81 0.65 0.64 0.52
Mercury <0.00010 <0.0002 <0.00010 <0.00010 <0.00010 <0.00010 <0.00010 <0.00010 <0.00010
Molybdenum <0.010 <0.010 <0.010 <0.010 <0.010 <0.010 <0.010 <0.010 <0.010
Nickel 0.040 0.048 0.022 0.027 0.024 0.021 0.016 0.015 0.011
Nitrate as N <1.0 0.13 <0.10 <0.10 <0.10 <0.10 <0.10 <0.10 0.12
Nitrite as N <0.12 <0.025 <0.025 <0.025 <0.025 <0.025 <0.025 <0.025 <0.025
Total <1.1 <1.1 <1.1 <1.1 <1.1 <1.1 <1.1 <1.1 <1.1
Nitrogen
pH,stu 4.93 4.83 4.78 4.80 4.64 4.37 4.34 4.08 4.03
Phosphorus <0.50 <0.50 <0.50 <0.50 <0.50 <0.50 <0.50 <0.50 <0.50
Potassium 24 13 9.1 8.4 7.5 6.1 4.6 4.5 3.9
Scandium <0.100 <0.100 <0.100 <0.100 <0.10 <0.10 <0.10 <0.10 <0.10
Selenium 0.040 0.057 0.039 0.042 0.018 0.0080 0.0054 <0.0050 <0.0050
Silver <0.0050 <0.0050 <0.0050 <0.0050 <0.0050 <0.0050 <0.0050 <0.0050 <0.0050
Sodium 20 12 6.4 4.0 1.6 0.83 0.76 0.55 0.90
Strontium 1.1 0.93 0.51 0.48 0.37 0.29 0.22 0.24 0.21
Sulfate 430 280 150 130 110 98 67 67 57
Thallium 0.0021 0.0015 <0.0010 <0.0010 0.0010 <0.0010 <0.0010 <0.0010 <0.0010
Tin <0.10 <0.10 <0.10 <0.10 <0.10 <0.10 <0.10 <0.10 <0.10
Titanium <0.10 <0.10 <0.10 <0.10 <0.10 <0.10 <0.10 <0.10 <0.10
Total 590 440 260 220 190 140 120 190 120
Dissolved
Solids
Uranium <0.0050 <0.0050 <0.0050 <0.0050 <0.0050 <0.0050 <0.0050 0.0057 0.0056
Vanadium <0.010 <0.010 <0.010 <0.010 <0.010 <0.010 <0.010 <0.010 <0.010
Zinc 5.9 4.9 2.8 2.7 2.4 1.9 1.8 1.8 1.4
Electrical 800 600 370 310 270 220 190 200 170
Conductivity,
pmhos/cm
The sample labeled TBWTC is the composite sample of the Creede Formation Portal+1391-ft, Portal
+380-ft and the Willow Creek Member rock units in proportions representative of material in the WRSF.
This test is ongoing; however results obtained thus far are presented below. pH is stable, ranging from
7.39 to 8.86.Sulfate concentrations are decreasing over the course of testing. Acidity has not been
detected during the test. Alkalinity concentrations are remaining stable. Iron was detectable at the
onset of testing but has been below detection since then.Conductivity has remained stable. Redox
values are relatively stable and not high enough to be associated with pyrite oxidation.
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