2010-04-14_GENERAL DOCUMENTS - C1981008 (2)

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Order 1 Sall Survey, Now Horizon Mine Interpretations The soil test location descriptions are typical and consistent for soil in the area. The Order I survey is a refinement of the "net yet published" Order III soil survey that the MRCS has conducted in the area. Map unit 98A occurs on alluvial terraces formed along Tuttle Creek. Profiles were described to 72 inches. Some areas may have, sail deeper than 72 inches and yield a slightly greater amount of salvage material. Map unit 98B occurs on steep mesa side slopes. Hardness of bedrock varies depending on the underlying strata. Coarse fragments range from channers to cobbles and are residual and colluvial in nature. "Valleycity soil has the sarne physical and chemical properties as those soils similarly named in the survey area. Valleycity is outside the range of characteristics compared to the survey area, in than it occurs in an area of 5 to 8 inches mean annual precipitation. Map unit 98C occurs can mesa summits, ridges and crests. hardness of bedrock varies depending on the underlying strata. Map unit 98D has thinner Quaternary eolian deposits than map unit 98E with a mean depth to bedrock of 34 inches. These deposits have developed cambic horizons, weak argillic horizons and secondary accumulations of carbonates. The accumulation of carbonates is reflected in a higher pH in the Bk and Btk horizons. The pH in A, Ap, ABt, Bw and Bt horizons (lift layer 1) averages 7.7 and in the Bk Btk and C horizons (lift layer 2) averages 8, 1. Map unit 98E ocrisists of areas of deep Quaternary coiian deposits. These {quaternary deposits overlie Dakota Sandstone and Burro Canyon Formations with depth to bedroom ranging 40 inches too greater than 72 inches with a mean depth of 53 inches, These deposits have stabilized and formed cambic horizons and in some places weak argillic horizons. Additionally, they have developed secondary accumulations of carbonates. The accumulation of carbonates is reflected in a higher pH in the Bk and Btk horizons. The pH in A, Ap, ABt, Bw and Bt horizons (lift layer 1) averages 7.7 and in the Bk Btk and G horizons (lift layer 2) averages 8.2_ Sail in this map unit is used primarily for irrigated pasture, hay crop and limited corn crop. Barx, irrigated sail is the second component in this map unit. Barx, irrigated is a prime farmland soil in Colorado $, This soil falls within the criteria listed in the National Soil Survey Haindbcok for prime farmland soil. However, in the Colorado Important Farmland Inventory page 3, "irrigated sails that have a pH higher than 7.4 are considered as having high conductivity and therefore are not considered prime" 4 Banc, irrigated as used in this survey is considered as not being prime farmland because the pH is higher than 7.4 in all horizons. Map unit 98F occurs in natural drainage areas that eventually form shallow valleys on the mesa and on the floodplain of Tuttle Creek. Depth to bedrock varies widely in this rnap unit. Haplargids with varying depths to bedrock form on drainage 1 3 Sail Survey of San Miguel Area, Colorado, Parts of Dolores, Montrose and San Miguel I Counties. Color2do Irnportant Farmland inventory, NRCS Colorado National Soil Survey Handbook, Chapter 657,5, Identification of Important Farmlands, NRCS, Washingtun DC, 1995 Edition. [� Page 14 of 44 Date D8111196 L,J