2013-03-26_REVISION - M1985026 (3)

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EXHIBIT E — RECLAMATION PLAN Field data recorded during sample collection included: Color— dark gray Texture — Very fine - grained clay and silt with larger clumps that are friable with moderate pressure between fingertips Plasticity— High Moisture — Moist The field sample was delivered to Aguirre Geotechnical Engineers of Englewood, Colorado, and the following tests were performed: Gradation Analysis — 1 1 /2" through No. 200 sieve Atterberg Limits — ASTM D -4318 Standard Proctor— ASTM D -698 Modified Proctor— ASTM D -1557 Data Analysis /Sample Material Suitability The results of the geotechnical tests are as follows: Gradation Analysis (Percent Fines) — 95.9% of material passed through a No. 200 sieve Atterberg Limits — Plastic Limit = 15 Plasticity Index = 24 Liquid Limit = 39 Standard Proctor— Optimum Moisture Content = 16.2% Laboratory Maximum Dry Density = 108.9 pcf Modified Proctor— Optimum Moisture Content = 13.9% Laboratory Maximum Dry Density = 117.7 pcf The overall goal in choosing a liner material is to obtain minimal hydraulic conductivity. Benson et al., 1992, has shown empirical relationships with respect to hydraulic conductivity between plasticity index, percent fines, and clay content. The ranges of hydraulic conductivities for the above three factors are shown in Table 1. Challenger Pit M-1980-026 TR -04 5 Page2of6