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Part A Temporary Facilities Pond As -Built <br />As required by Rule 4.05.9 (14), the following report is provided to document construction <br />information upon completion of construction. <br />Design information for the pond is presented in Volume 18, Exhibit 7, Item 23, Part K. <br />The as -built drawing for the Temporary Facilities Pond is provided in Figure 7-26A-1 and <br />includes plan view, cross-sections, and spillway details. The impoundment will be operated as a <br />zero discharge facility for storm water runoff up through the 25 -year, 24-hour storm from the <br />entire drainage area. The emergency spillway consists of a minimum 2 -foot deep vegetated <br />channel with a 20 -foot bottom width and 3H:1V side slope. <br />The as -built condition of the pond is approximately 3 to 4 feet lower than the design. The <br />elevation of the entire pond was dropped during construction due to deeper topsoil encountered <br />during stripping than was anticipated during the design of the Temporary Facilities Pond. <br />The Temporary Facilities Pond was constructed from April to May of 2017, and was regularly <br />inspected throughout construction by a qualified registered professional engineer. The <br />embankment was constructed with fill material that was free of any unacceptable fill material as <br />outlined in the Exhibit 7, Item 23, Part K. Compaction, optimum moisture, and maximum dry <br />density testing was performed in the field and is presented Appendix 7-26A-1. All final field <br />density tests indicated a 95% standard or greater compaction was achieved. <br />Two SEDCAD models are provided for this Temporary Facilities Pond as -built condition and are <br />provided in Appendix 7-26A-2. The first demonstration indicates the 3.09 ac -ft capacity of the <br />Temporary Facilities Pond below the emergency spillway is adequate to store the total runoff <br />volume into the pond of 1.33 ac -ft as generated by the 10 -yr, 24 -hr storm event. The SEDCAD <br />demonstration for the 25 -yr, 24 -hr storm event indicates the 3.09 ac -ft capacity of the Temporary <br />Facilities Pond below the emergency spillway is adequate to store the total runoff volume into <br />the pond of 2.61 ac -ft generated by the 25 -yr, 24 -hr storm event. <br />The final embankment will be broadcast seeded with the seed mixture outlined in Volume 15, <br />Section 4.05.6 Sedimentation Ponds. <br />Exhibit 7 Item 26 Page Exh. 7-23A-1 Revision Date: 6/13/17 <br />Revision No.: TR -112 <br />