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1 <br /> However, after the five year analysis cycle the ending moisture content was above <br /> field capacity. Therefore, when modeling the active area with run-off, intermediate <br /> cover, and final closure areas, the initial moisture content was assumed to be at <br /> field capacity. This was considered a conservative or"worst case" condition in the <br /> sense that the moisture storage capacity of the soil cover and refuse is discounted. <br /> C. Landfill Area Models <br /> The following assumptions were made for the representative landfill areas for the <br /> cover and refuse layers: <br /> 1. Exposed Liner: Area of the landfill which has no in-place refuse but routes <br /> storm water to the leachate collection system. Assumes that 1000/0 of the <br /> precipitation would be collected. <br /> 2. Active Area with No Run-off: Assumes no run-off from landfill area, rather <br /> it infiltrates into the waste mass, which is below field capacity and can <br /> temporarily absorb the moisture. This also represents areas with minimal <br /> drainage slope. Cover and refuse layers modeled as follows: <br /> Daily Cover: 6" @ 3.7 x 10'4 cm/sec hydraulic conductivity <br /> Refuse: 300" @ 2 x 10'4 cm/sec hydraulic conductivity, initial moisture <br /> content set at 0.2 vol/vol. (0.29 field capacity) <br /> 3. Active Area with Surface Water Run-off: Assumes run-off cannot be routed <br /> off landfill area or may be contaminated with leachate and is routed to the <br /> leachate system. HELP model data for lateral drainage and run-off are <br /> combined for the leachate generation estimate. Cover and refuse layers <br /> modeled as follows: <br /> Daily Cover: 6" @ 3.7 x 10'4 cm/sec hydraulic conductivity <br /> Refuse: 300" @ 2 x 10'4 cm/sec hydraulic conductivity, initial moisture <br /> content set at field capacity. <br /> 4. Intermediate Cover: Assumes a soil cover Is placed over the refuse prior 1 <br /> to final closure and surface water run-off can be routed off landfill surface. <br /> Cover and refuse layers modeled as follows: I <br /> Interim Cover: 12" @ 2 x 103 cm/sec hydraulic conductivity <br /> Refuse: 300" @ 2 x 10'4 cm/sec hydraulic conductivity, initial moisture I <br /> content set at field capacity. <br /> 5. Final Closure: Assumes9 eomembrane cover system.Geomembrane liner ; <br /> leakage factor set at 0.001 assuming fair quality assurance and quality <br /> control during construction. <br /> r <br />