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1999 Soil Sampling: Seneca Mine, Hayden Colorado <br />Rock Fragments- Rock fragments average 5 percent and ranges 2 to 10 <br />• percent. Rock Fragments are predominantly gravel size (2mm io 75mm) of <br />sedimentary origin, primarily sandstone. <br />Structure- The upper horizon in both sample pits are moderate coarse and <br />very coarse platy. The resultant structure and depth of the structure is <br />consistent with a mechanically disked layer but is moderately compacted. The <br />lower topsoil horizon is strong coarse and very coarse angular blocky <br />structure. This indicates moderate compaction. Vegetation analysis discussed <br />below did not indicate that such structure is presenting a problem to plant <br />growth. <br />Consistence- The dry consistence of the upper topsoil layer is hard. Moist <br />consistence is friable. Consistence of the lower topsoil horizons is higher than <br />typical for textures of loam. Dry consistence is very hard. Dry consistence <br />indicates moderate compaction through the use of mechanical equipment for <br />soil redistribution. Moist consistence is friable to firm. Vegetation analysis <br />discussed below did not indicate that such consistence is presenting a <br />problem to plant growth. <br />Lab Data- Lab data is located in Appendix II. Both the upper and lower topsoil <br />horizons, differing only in their mechanical treatment, have the same chemical <br />properties. pH ranges 7.0 to 7.3 and averages 7.2 which is neutral. Organic <br />• matter averages 4.5 percent and ranges 4.3 to 4.8. These results and all <br />other lab data indicates topsoil in all sample pits is suitable (Appendix III, <br />Table-2). <br />Subsoil- The same sample pits were sampled for subsoil/spoil from the bottom of <br />the topsoil horizon to a depth of five feet. Field descriptions are located in Appendix <br />IV and lab data is located in Appendix II. All subsoil in all sample pits classify as <br />suitable subsoil (Appendix III, Table-2). SEN-1-99 is a dryland grass/forb site and <br />SEN-2-99 is a shrubland site. Both sites are in their second year of growth. The <br />results follow: <br />Depth- The average depth to the start of subsoil is 11 inches (0.9 feet) below <br />the surface. Depth to subsoil ranges 10 to 12 inches (.8 to 1.0 feet) and <br />extends to a depth greater than 5 feet in sample pit SEN-2-99 and to a depth <br />of 1.5 feet in SEN-1-99. Below 1.5 feet at SEN-1-99 is cobble and stone size <br />spoil. <br />Textures- Textures are loams. Clay content averages 26 percent and ranges <br />26 to 27 percent, sand content averages 42 percent and ranges 40 to 43 <br />percent. Silt content averages 32 percent and ranges 30 to 34 percent. <br /> <br />Page 6 of 11 <br />02/09/00 <br />