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7-6f .3C) to show that the as-built configuration can safely pass the 25- year, 29-hour discharge. The channel utility modeling shows a peak flow depth of approximately 0.9 feet, which would be approximately 3.8 feet below the top of the embankment (7,020.0 feet). If the principal spillway were to clog, or become inoperable for some other reason, the modeling shows that the emergency spillway is of sufficient size to safely pass the peak discharge from the 25-year, 29-hour storm event. Pond 008 is constructed and operated in compliance with Rule 4.05.9(2)(c)(ii). Certification Statement The impoundment and emergency spillway are pre-existing. The original design, as-built plans and modifications were prepared under the supervision of others. Pond 008 was originally constructed as shown on Exhibit 7-17A, Sediment Pond 008 As-Built, which was certified by Ronald J. Gehrke, a registered professional engineer in the State of Colorado experienced in the design and construction of earthen structures. The trapezoidal emergency spillway was constructed in 1992 as shown on Exhibit 7-17C, Sediment Pond 006 As-Built, and which was certified by Mike Alltavia, a registered profession engineer in the State of Colorado experienced in the design and construction of earthen structures. I am a registered professional engineer in the State of Colorado experienced in the design, construction and operation of earthen structures. I have reviewed the as-built documents and inspected the site. Exhibit 7-17E, Pond 006 Principal Spillway Replacement As-Built, presents the existing configuration of the pond, including the new principal spillway. It is in my opinion, based on the design assumptions presented in Appendix 7-6e and the 2005 as-built data, that Pond 008 will meet the requirements of Rules 9.05.6(3)(a), 9.05.9(2)(b) and 9.05.9(2)(c)(ii). L J TR-37 4 Revised 10/OS