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3. Two of the four boreholes did not encounter dense sand and gravel deposits at depth. <br />Those boreholes encountered shale and fine grained soils with little gravel. It appears <br />that the mesa has been scoured to shale as an undulating surface and varying amounts <br />of fines (silt and clay), sand and gravel were subsequently deposited. <br />4. According to the NRCS Web Soil Survey mapping, the soil type proposed to be mined is <br />"Mesa clay loam, 0 -2% slopes" (map unit #760). This soil is a clay, clay loam and <br />gravelly clay to 44 inches underlain by cobbly loamy coarse sand to 80 inches, which is <br />the vertical extent of their mapping. It is identified to have "poor" potential as a gravel <br />or sand resource. I asked our local NRCS soil scientist, Dave Dearstyne, how they <br />comment on a gravel resource when they map to less than 7 feet. He said it is based <br />on their view of the landform upon which the soil develops. In other words, if the <br />mapper does not observe sufficient (i.e. less than 10 to 15 feet of) gravel on the mesa <br />to warrant a resource, they label it as a "poor" resource. <br />Although there does appear to be gravels on the mesa proposed to be mined, it is our opinion <br />that the gravel deposit is highly variable in thickness and quality and our number of boreholes <br />was insufficient for a resource -level assessment. To base an entire mine development plan on <br />two positive geotechnical boreholes and no laboratory testing is optimistic and likely unrealistic. <br />Therefore, we would like to see a more thorough and substantiated analysis of a resource like <br />this before consideration is given to development of this deposit. Given the controversy that <br />this proposed gravel pit has caused due to potential impacts to wildlife, traffic, dust, noise, <br />water, property values, and quality of life for the local inhabitants, we suggest a comprehensive <br />exploratory examination of the quality of the deposit before more is invested by individuals, the <br />community and Montrose County. <br />Sincerely, <br />Laurie J. Brandt, P.G. <br />Professional Geologist <br />Cc: Steve White, Montrose County Planning & Development Director <br />Montrose County Board of County Commissioners <br />Page 2 of 2 <br />