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The wet detention basin/wetland has the following design characteristics; <br />Basin i <br />• Normal pool elevation «■ 945.5 <br />• Overflow elevation = 946.0 <br />• Surface area at elevation 945.5 » 0.5 acres <br />• Mxximun! normal pool depth = 10 feet <br />• Average depth » 5.4 feet <br />• iOtal normal pool volume =■ 2.7 acrc'feet <br />• Side slopes = 3:1 <br />Basin 2, <br />• Normal Pool Elevation » 944.5 <br />• Surface area at elevation 944.5 = 0.35 acres <br />• .Maximum normal pool depth « 3.5 feet <br />• Average depth « 3.7 feet <br />• Total normal pool volume 1,3 acre-feet <br />• Side slones » 3:1 <br />OgQtCChnical/AnaJvtical Resuits and Considerations <br />Soil borings were drilled at tour locations on the site. At each boring, continuous split spoon <br />samples were collected and Shelby tube samples were taken at selected locations and depths. <br />Based on the geotechnical information, the soils in the vicinity of the proposed basins are <br />adequate to allow for 3:1 sideslopes (See Appendix B). <br />One soil sample was composited from 0-14 feet from borings LL 1-2 and a second soil <br />sample was composited from 0-14 feet from borings LL 3-4. The samples were analyzed for <br />the tollowing categories of chemical compounds: herbicides, metals, pesticides, <br />polychlorinated biphenyls (PCBs) and semivolatiles. <br />Low levels of seraivolatiles or PAHs were detected in both samples as weU a minor <br />of the herbicide 2,4-DB. The metal compounds were all detected within normal background <br />concentration ranges. .°esticides and PCBs were not detected (See Appendix C). It is not <br />anticipated that any special disposal requirement wiil be necessary for the above soils. <br />M:\CIUVM*30rvDi»ipLRIT-A£S-Qy