2012-01-06_PERMIT FILE - C1982057 (16)

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Review of Existing Information. All existing soils and related discipline information for the study area was compiled, reviewed, and evaluated prior to initiation of field work. An Order 2 • and 3 soil survey is currently beinl7 finalized for Routt County by the Craig Field Office of the USDA Natural Resources Conservation Service (NRCS, formerly the Soil Conservation Ss•rvicel. A copy of the existing NRCS maps covering the study area, official soil series descripti~orts, soil interpretation records, map unit de~seriptions, and all range site information was obtained and reviewed (USDA-SCS open file report, 1979, 1990, and 19971. Field Mapping (Orders 1/2/31. The study area was first examined in a reconnaissance manner to familiarize the field soil scientist with the area. Following the low-intensity orientation survey, ahigh-intensity soil survey (Order 1/21 at 1:4800 scale was conducted over most of the study area. The Order 2/3 USDA-NRCS soil survey was used to delineate the soil types within the May 1985 and April/May 1989 study areas of the Tie-Across Haul Road corridor and the Pond 009 watershed area 11 990 survey) outside of the permit boundary. Soil profiles were excavated as necessary to determine the nature and extent of soils present on the study area. Pits were hand dug to depths of 24 to 36 inches, to a paralithic comtact or to bedrock, whichever was shallower. The 36-inch depth was sufficient to expose the upper genetic soil horizons of all soils encountered in the area. Below the 24-to-36 inch depth, the soils were examined by means of zi 2 '/.-inch diameter hand auger to a depth of 60 inches, or to a paralithic contact or bedrock, whichever was shallower. Each soil profile was • characterized and then correlated with available NRCS soil series criteria. Mr. Darrell Schroeder, NRCS Soil Scientist for the Craig Field Office, and Mr. Gib Bowman, NRCS State Soils Correlator for Colorado were contacted for specific information and discussion. Soil series phases and phases of series variants were delineated primarily on the basis of surface texture and slope. Small areas (less than two acres in size) of steeper or flatter slopes or slightly different surface textures were not broken out into separate phases. After determining the soil series, and thie surface phase to which each profile belonged, thie soil phase boundaries were determined throughout their length in the field, primarily by means of additional soil characterization auger holes and secondarily by analysis of relative landscape type, topographic position, parent material, drainage pattern, vegetative indicators, and visible surface soil features. The soil boundaries were then delineated on the 1:4800 11' = 400'1 scale topographic base maps (dated 7/11/71, 5/22/72, and 7/1/991. The original soil boundaries as delineated for the area that became the II-W South Extension Area were confirmed or revised during the 1997 survey and then transferred to a new 1:4800 (1" = 400') scale topographic base map (dated 19981. Map units were traversed along drill hole access roads, fence lines, and game trails. The cut banks of fence lines and access roads were observed whenever available to confirm map unit • 8 Revised 9198