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Exhibit 7, Item 14 <br /> Lower Administration Building Small Area Exemption <br /> The disturbed area that contained the Lower Administration Building cannot be captured within <br /> a traditional sediment control system of ditches and a sediment pond. In accordance with Rule <br /> 4.05.2(3)(a), this demonstration meets the criteria for an exemption from the requirements of <br /> 4.05.2.; therefore, it will be treated through a small area exemption. This area is depicted on <br /> Figure Exh. 7 Item 14-1 and is comprised of 4.4 acres of disturbance. <br /> For the model demonstration, SEDCAD's grass filter routine has been used to demonstrate that <br /> runoff from this area will meet the effluent standards of 0.5 ml/1 in accordance with Rule <br /> 4.05.2(7) (US EPA, 40 C.F.R. §434.52). The 4.4 acre area has a ground slope of 8.1%, a curve <br /> number of 85 was utilized to reflect a topsoil and seeded condition, and both were used to <br /> generate the runoff hydrograph from a 10 year 24 hour storm. Sedimentology parameters as <br /> defined in Exhibit 7 Methodologies and Assumptions for Sedimentation Pond Designs <br /> Evaluations were used to generate the accompanying sediment graph. <br /> The demonstrations utilized the Manning's roughness coefficient of 0.0054, and a stem spacing <br /> of 0.86 inches. These inputs are intended to reflect that the native grass cover density adjacent to <br /> the small area exemption. The 3.17 cfs flow was then run through a native grass filter <br /> approximately 215 feet wide and only 900 feet long (in the direction of the flow). <br /> As shown in the attached SEDCAD output files, the calculated resulting peak settleable <br /> concentration released and the 24-hr weighted settleable solids concentration is 0.00 ml/l. <br /> Therefore, both cases are well below the effluent standards of 0.5 ml/1. <br /> Exh. 7, Item 14, Page 1 Revision Date: 6/7/16 <br /> Revision No.: TR-107 <br />