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Coulson Excavating Company, Ine. - Bonser Pit Exhibit I -Soils Information An order 2 soil survey of the soils at the proposed Bonser pit was completed in January, 2000. Soils observed in the reconnaissance and shown on the Permit Area Map (Figure 1) include Table Mountain loam, 0 to 1 percent slopes; and Nunn clay loam, 1 to 3 percent slopes. The Table Mountain series is classified as fine-loamy, mixed, mesic Pachic Haplustolls (Soil Survey of Lazimer County Area, Colorado, 1980). These soils have adark-colored, loamy surface horizon 30 to 50 inches thick. Although the deep, dark surface horizon in Table Mountain soils is suitable for topsoil salvage, salts (indicating high salinity) were evident at various depths across the site. Where salts were noted above 12 inches in this unit, the soil is denoted as Table Mountain-saline soils. Recommended topsoil saivage depths are I S inches in Table Mountain delineations and 9 inches in Table Mountain- saline delineations. Based on these depths, approximately 85,647 yd3 of Table Mountain topsoil will be removed and salvaged for reclamation; and roughly 37,080 yd3 of Table Mountain-saline topsoil shall be removed and salvaged for reclamation. Underlying material is lighter colored fine sandy loam to about 66 inches, and mixed sand and gravel below this depth. The underlying material is also suitable as subsoil for reclamation The Nunn series is classified as fine, montmorollonitic, mesic Aridic Argiustolls (Soil Survey of Lazimer County Area, Colorado, 1980). These soils have a thin dark-colored, clay loam surface horizon to approximately 6 inches. Subsoil to 30 inches is clay loam to heavy clay loam, dazk-colored in the upper part becoming lighter in the lower part. Substratum is clay loam to 60 inches or more. Sand and gravel material may occur at depths of 60 to 80 inches. The surface horizon in Nunn soils is suitable for topsoil salvage to a depth of I8 inches, which will produce about 7,092 yd' of salvageable material (Table ] ). A total of approximately 129,819 yd3 of topsoil and 152,505 yd3 of subsoil will be salvaged for reclamation. The total amount of overburden will cover the reclaimed pit to a depth of approximately 2.5 ft. The Natural Resources Conservation Service (NRCS), formerly the Soil Conservation Service (SCS), has federal responsibility for the identification of prime farmland. Prime farmland is our nation's most productive agricultural land. Both Table Mountain loam, 0 to 1 percent slopes ,and Nunn clay loam, 1 to 3 percent slopes, aze listed as prime farmland, if irrigated, by the MRCS. The Larimer County Soil Survey confirms the presence of prime farmland units over this area. Most of the pit location is or has been historically irrigated. Therefore, site conditions conform that the pit location qualifies as prime farmland as denned by the NRCS.