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assumed to weather in response to the same conditions that would affect a prescriptive <br />cover, the soil characteristics in the two model scenarios are the same. As a result, the <br />most significant difference between the two models is the root distribution which is <br />limited to the one -foot vegetative layer in the prescriptive case but extends to a three feet <br />in the alternative case. <br />4.4.1.1 SOIL MOISTURE RESULTS <br />Figure 2 depicts the modeled moisture content of the modeled degraded <br />prescriptive final cover soils in percent by weight for six distinct depth intervals <br />over a period of approximately ten years. As can be seen, in all cases for the <br />constant potential boundary condition the shallow layers (3 -inch, 9 -inch, 15 -inch <br />and 21 -inch) mimic seasonal precipitation patterns throughout the modeling <br />period, while the deeper soil layers reflect only severe precipitation events. <br />4.4.1.2INFILTRATION <br />Figure 3 depicts the calculated net flux through the layers of the modeled <br />prescriptive final cover profile for the constant potential bottom boundary <br />condition. As shown therein, infiltration potential for the prescriptive final cover <br />is estimated to be about -0.69 inches/year. This value represents the performance <br />for a degraded clay prescriptive final cover over the FSL. , <br />4.4.2 ALTERNATIVE FINAL COVER <br />As summarized above, the FSL non -prescriptive cover was modeled as a four foot thick <br />(1219 -mm) alternative cover composed of compacted on-site borrow soils combined with <br />shallow to intermediate rooting native vegetation. The results of the modeling performed <br />for this study are presented in Figures 4 and 5. <br />4.4.2.1 SOIL MOISTURE RESULTS <br />Figure 4 depicts the modeled moisture content of the alternative final cover soils <br />in percent by weight for several distinct depth intervals over a period of <br />approximately ten years. Figure 4 represents the moisture conditions anticipated <br />under the constant potential bottom boundary and also summarizes the rainfall <br />history recorded at the Western Regional Climate Center's Stockton Station. As <br />can be seen, the soil layers mimic seasonal precipitation patterns throughout the <br />modeling period, though only the larger events penetrate to the deeper soil layers. <br />4.4.2.2 INFILTRATION <br />Figure 5 depicts the net flux through the layers of the modeled alternative final <br />cover profile under a constant potential bottom boundary condition. As shown, a <br />negative flux potential of about —12.60 inches/year is calculated. <br />so <br />C.uoas-DO82TORWAxwForwardCO VEXD007nsnoas <br />Geo Logic Associates <br />