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Eric Scott <br /> RE:Response to Preliminary Review of a 112 Construction Materials Reclamation Permit Application Package, <br /> Tollgate Pit,File No.M-2018-060 <br /> February 15, 2019 <br /> Page 3 of 7 <br /> FEMA NFHL <br /> } 7 <br /> t I � :g �rturEa <br /> 8 i23(s 150aE 8123C 1 8E ~'^ <br /> Goo 'Fe <br /> 1 <br /> FIGURE 1. FLOODPLAIN LOCATION IN PROPOSED MINING AREA. <br /> In accordance with the UDFCD guidelines, a side channel spillway with a 100-foot bottom width and <br /> 3H:1 V side slopes was determined to be necessary. The location of the side channel spillway is near the <br /> southwest corner of the pit, corresponding to the location where overtopping of Storms Lake Drainage is <br /> expected to first occur. In order to not decrease the carrying capacity of Storms Lake Drainage,the spillway <br /> channel will begin to the east of Storm's Lake Drainage's easement. The spillway channel will have an <br /> approximate 3%slope towards the east into the mined area,and will primarily be vegetated for most of the <br /> length. Near the start of the spillway rundown to the pit, the vegetated channel bottom will transition to <br /> Type M riprap, a concrete cutoff wall,and finally a spillway-grade concrete rundown along the 3:1 mined <br /> slope to a point 5 feet below the high water mark; here the rundown will transition back to Type M riprap <br /> to the bottom of the mined area.The length of the concrete channel transition from the edge of the pit is to <br /> be determined depending on the location of the slurry wall. For cost estimating purposes, this length is <br /> assumed to be 10 feet from the edge of the pit with another 5 feet to the concrete cutoff wall. <br /> Note that the specified design utilizes one of the slope protection methods(concrete spillway)suggested by <br /> the UDFCD. Equivalent spillway protection may also be used,including grouted boulders,soil cement,or <br /> concrete pavers. <br /> EXHIBIT F—Reclamation Plan Map(Rule 6.4.6): <br /> The reclamation plan map (attached, F-1) has been updated in order to show proposed topography of the <br /> reclaimed area. The design for the armored inlet channel is also included on this map. <br /> EXHIBIT G—Water Information(Rule 6.4.7): <br /> www.applegategroup.com Denver • Glenwood Springs • Hotchkiss (303)452-6611 <br />