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1999 Soil Sampling: Seneca Mine, Hayden Colorado the site. Achieving adequate vegetative cover could be problematic over time. Site • conditions can only be ameliorated if more subsoil is available. Ripping on the contour to reduce compaction can also be problematic if ripping penetrates past 1.5 feet. Infiltration will bypass the soil medium and drain through the porous cobble stone spoil. It is recommended that further sampling occur at this site to determine whether the depth to cobble stone spoil material is typical or an anomaly. SEN-2-99 is suitable and, lacking an overly enthusiastic wildlife foraging campaign, should yield a productive shrubland community. Fertilizer application for the area is not indicated especially since there is already high organic matter levels. Seneca II-W 10 sites were sampled on approximately 150 acres of land. Field descriptions are located in Appendix IV and lab data is located in Appendix II. Topsoil- All topsoil in all sample pits classifies as suitable topsoil (Appendix III, Table-2). 2W-5-99 borders on marginally suitable as texture straddles the clay loam- clay boundary. All other indications of 2W-5-99 result in a classification of suitable topsoil. The results follow: Depth- The average depth of topsoil is 20 inches (1.7 feet). Depth of topsoil ranges 10 to 25 inches (.8 to 2.1 feet). The topsoil in all sample pits consisted of two horizons. The upper horizon averages 8 inches of thickness and • ranges in depth from 6 to 10 inches in thickness. The lower topsoil horizon averages 12 inches in thickness and ranges from 6 to 16 inches in thickness. The difference in horizons is due to structure and dry and moist consistence discussed below. All other characteristics between horizons are the same. Textures- Textures range loam to clay loam. One sample bordered on clay (2W-5-99) and one sample was a sandy clay loam (2W-9-99). Clay content averages 26 percent and ranges 20 to 40 percent, sand content averages 34 percent and ranges 20 to 46 percent. Silt content averages 40 percent and ranges 27 to 47 percent. Rock Fragments- Rock fragments average 5 percent and range 0 to 20 percent. Rock Fragments are predominantly gravel size (2mm to 75mm) of sedimentary origin, primarily sandstone. Structure- The upper horizon in all sample pits except two are moderate medium and coarse platy structure. The resultant structure and depth of the structure is consistent with a mechanically disked layer. Two sample pits 2W- 1-99 and 2W-5-99that are located on gentle slopes of S and 12 percent and have strong coarse and very coarse platy structure indicative of extra traffic and a resultant increase in compaction. 2W-5-99 borders on clay and the • resultant stronger structure may be due to the higher density of the clay. Vegetation analysis discussed below did not indicate that either of these two Page 8 of 11 02/09/00