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includes the absence of any analysis regarding changes in floodplain conditions in the area due to <br /> mining activity, the heightened flooding risks for surrounding neighborhoods, and other site <br /> reclamation alternatives that Western Mobile considered which would not require a flood <br /> protection barrier. Ultimately, the proposed reclamation plan amendment is completely silent <br /> regarding a significant matter of concern to the safety and welfare of those City of Boulder and <br /> Boulder County citizens who reside in close proximity to the Deepe Farm Pit mining site. <br /> It is worth noting, as well, that the existing land berm was never designed to federal standards or <br /> inspected by a public agency during construction. Further, there has been no formal review of the <br /> floodplain management implications, long-range impacts, potential risks, or community <br /> acceptability of such a permanent flood protection levee system. To the contrary, the City of <br /> Boulder and Boulder County have continued to express opposition to establishment of a <br /> permanent flood protection levee on the Deepe Farm Pit mining site without exhaustive <br /> consideration of all possible alternatives to a levee system. To this end, the City of Boulder <br /> requests that the DMG refrain from adopting the proposed reclamation plan amendment for the <br /> Deepe Farm Pit until there is a final determination of the appropriate flood mitigation measures <br /> for the area. <br /> Land Grades <br /> Attached are a series of cross-section maps comparing the proposed 1996 reclamation plan <br /> amendment with the previously approved 1989 and 1991 reclamation plans. The proposed <br /> amendment reflects the added land berm/flood levee in detail at several sections around the <br /> perimeter of the Deepe Farm Pit. The cross-sectional illustration identifies the significantly lower <br /> grade of the mined site than in previously approved reclamation plans. These lower grades have: <br /> created the potential to divert and redirect flood waters from South Boulder Creek to the north. <br /> It is important to note that the Deepe Farm Pit mine differs from mines that are excavated into <br /> creek valleys, creating large holes which form lakes. The Deepe Farm Pit mine was excavated <br /> into the side of an alluvial deposit, essentially forting a new perpendicular channel below the <br /> invert of South Boulder Creek which directs flows away from the creek along a positive outfall. <br /> This man-made change in topography can cause catastrophic flooding in local neighborhoods <br /> north of the Deepe Farm Pit. Original site reclamation plans proposed to restore the site to pre- <br /> mining grades using earth fill from the excavation of several deep lakes on the property. These <br /> measures would have eliminated the potential for dramatically redirecting South Boulder Creek <br /> flood waters. The proposed reclamation plan amendment, encompassing lower land grades and <br /> incorporation of a flood protection levee system, represents a much more dramatic shift from <br /> floodplain conditions under pre-mining natural grade conditions. <br /> Current Floodplain Study <br /> The City of Boulder, Boulder County, and Urban Drainage and Flood Control District (UDFCD) <br /> recently contracted with Taggart Engineering Associates (Taggart) to conduct a detailed study of <br /> the South Boulder Creek floodplain in the vicinity of the Deepe Farm Pit. This study will include <br /> a master planning effort for the South Boulder Creek floodplain. The master planning effort will <br />