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

HCT Test Results
TBWTC
Effluent Redox Conductivity Total Fe Sulfate Acidity Alkalinity
Week pH mV µS/cm mg/I mg/I mg/I mg/I
0 7.44 306 426 0.90 140.0 0 36
1 7.36 307 422 <0.10 140.0 0 24
2 7.41 293 264 <0.10 90.0 0 28
3 7.85 309 161 <0.10 40.0 0 34
4 7.39 327 97.5 <0.10 20.0 0 23
5 7.73 336 93.4 <0.10 10.0 0 22
6 7.60 337 103 <0.10 30.0 0 25
7 8.86 331 94.4 <0.10 20.0 0 33
8 8.15 296 80.3 <0.10 20.0 0 28
9 8.03 319 83.8 <0.10 20.0 0 29
10 7.81 318 81.6 <0.10 8.0 0 26
11 7.81 325 61.5 <0.10 4.0 0 22
12 7.73 361 95.6 <0.10 5.0 0 36
*13 8.17 302 90.8 <0.10 6.0 0 37
*Test is ongoing
During HCT testing,effluent samples were collected and submitted for analytical testing. The following
table includes results for the composite HCT. Concentrations of metals were measured at
concentrations near or below method detection limits,or followed a decreasing concentration trend
during testing.
HCT Test TBWTC-HC Analytical Results
Analysis, mg/L Week 0 Week 1 Week 2 Week 4 Week 8 Week 12
Alkalinity,CaCO3 38 22 29 21 27 39
CO3, CaCO3 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0
HCO3 38 22 29 21 27 39
Aluminum <0.045 <0.045 <0.045 <0.045 <0.045 <0.045
Ammonia,as Nitrogen 0.11 <0.050 <0.050 <0.050 <0.050 <0.050
Antimony 0.0055 0.0086 0.010 0.011 0.010 0.0097
Arsenic 0.011 0.021 0.034 0.053 0.044 0.044
Barium 0.015 0.035 0.019 <0.010 <0.010 0.015
Beryllium <0.0010 <0.0010 <0.0010 <0.0010 <0.0010 <0.0010
10