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Coulson Excavating Company, Inc. - Bonser Gravel Pit <br />Exhibit E -Reclamation Plan <br />Texture -Very fine-grained clay and silt with larger clumps that are friable with <br />moderate pressure between fingertips <br />Plasticity -Low <br />Moisture -Moist <br />The field sample was delivered to Aguirre Geotechnical Engineers of Englewood, <br />Colorado, and the following tests were performed: <br />Gradation Analysis -1 ''/z' through No. 200 sieve <br />Atterberg Limits -ASTM D-4318 <br />Standard Proctor -ASTM D-698 <br />Moditted Proctor-ASTM D-1557 <br />Data Analysis/Sample Material Suitability <br />The results of the geotechnical tests are as follows: <br />Gradation Analysis (Percent Fines) - 95.9% of material passed through a No. <br />200 sieve <br />Atterberg Limits -Plastic Limit = 15 <br />Plasticity Index = 24 <br />Liquid Limit = 39 <br />Standard Proctor- Optimum Moisture Content = 16.2% <br />Laboratory Maximum Dry Density = 108.9 pcf <br />Modified Proctor- Optimum Moisture Content = 13.9% <br />Laboratory Maximum Dry Density = 117.7 pcf <br />The overall goal in choosing a liner material is to obtain minimal hydraulic <br />conductivity. Benson et al., 1992, has shown empirical relationships with respect <br />to hydraulic conductivity between plasticity index, percent fines, and clay content. <br />The ranges of hydraulic conductivities for the above three factors are shown in <br />Table 1. <br />Table 1 <br />Empirical Relationship Range Of Hydraulic Conductivity <br /> (feet/day) <br />Plasticity Index (as measured) and 5.6x10- to 8.4x10 <br />Hydraulic Conductivity <br />