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In the event of an exceedance of a state water quality standard during offsite discharge of <br />dewatering flows from the proposed Tanabe site, to the extent that the CDPHE must be notified, <br />the applicant will submit a copy of the notice to the Division. <br />The Division concludes [hat the operator has adequately minimized possible impacts to surface <br />and groundwater of the affected land and surrounding area during both mining and reclamation. <br />3. Slope Stability <br />"A soils and geotechnical report prepared by CTL Thompson, Inc. for Pinnacle Pines LLC in <br />their application to Commerce City discourages using steep slopes for long term stability. Have <br />any soils and geotechnical studies been completed on the applicant's site?" <br />Response -During mining, pit slopes will be approximately 0.5:1. The operator has committed <br />to a minumum setback distance of two (2) times the depth of excavation for any permanent man- <br />made structures within 200 feet of the toe of the pit excavation. During final reclamation, pit <br />slopes will be recontoured to 3:1 in conformance with Rule 3.1.5(7) of the Construction <br />Materials Rules and Regulations for lakes. <br />4. Stormwater <br />a. "The application does not address the regional impacts of storm water flows and quality for <br />portions of the Phase 1 operation that aze located in Zone A of the FEMA floodplain for 1st <br />Creek." <br />Response -The proposed operation is located within the floodplain, but not the channel of Ist <br />Creek. Stormwater from the site will not be routed to the 1st Creek floodway channel. <br />b. "This site is in or near the lst Creek Regional Drainage Way floodway/channel. It is <br />extremely important that this channeUfloodway is available to convey storm water drainage from <br />the entire 1st Creek drainage basin to the South Platte River. Therefore, we conclude that this <br />operation as requested may alter the ability for the drainage to be conveyed through here and will <br />negatively impact the regional drainage system." <br />Response -The applicant anticipates that the site grading will direct all Stormwater that contacts <br />lands disturbed by the proposed mining operation into the Phase I or Phase II pits. Therefore, the <br />applicant does not plan to install any Stormwater drainage stntctures within or immediately <br />adjacent to the floodway channel. In pursuit of the applicable Floodplain Use Permit required by <br />Adams County, the applicant is continuing discussions with the Urban Drainage & Flood Control <br />District to address their concerns. Also, the applicant's plans for reclamation of a wetland in the <br />Phase 1 portion of the operation (near the Ist Creek Channel) is not expected to increase the <br />