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1999 Soil Sampling: Seneca Mine, Hayden Colorado <br />sites are problematic. The lower topsoil horizon is consistently moderate <br />coarse and very coarse subangular blocky structure. This is consistent with <br />mechanical redistribution of soil. Vegetation analysis discussed below did not <br />indicate that such structure is presenting a problem to plant growth. <br />Consistence- The dry consistence of the upper topsoil layer ranges from <br />slightly hard to hard, typical of disked soil and consistent with loam and clay <br />loam textures that have been mechanically manipulated. Both 2W-1-99 and <br />2W-5-99 had very hard dry consistence, consistent with compaction and clay <br />content. Moist consistence was very friable to friable except for sample pit <br />2W-5-99 which has a consistence of firm, consistent with clay content. <br />Consistence of the lower topsoil horizons is one grade higher than typical for <br />textures of loam and clay loam. Dry consistence averages very hard with a <br />range of hard to extremely hard. Dry consistence indicates moderate <br />compaction through the use of mechanical equipment for soil redistribution. <br />Moist consistence averages friable and ranges friable to firm and is typical of <br />loam and clay loam soil textures. Vegetation analysis discussed below did not <br />indicate that such consistence is presenting a 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 6.5 to 7.8 and averages 7.3 which is neutral. Organic <br />matter averages 4.9 percent and ranges 3.6 to 7.0. These results and all <br />• other lab data indicates topsoil in all sample pits as 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 classifies as <br />suitable subsoil (Appendix III, Table-2). 2W-5-99 classifies marginally suitable as <br />texture is clay. All other indications of 2W-5-99 result in a classification of suitable <br />subsoil. The results follow: <br />Depth- The average depth to the start of subsoil is 20 inches (1.7 feet) below <br />the surface. Depth to subsoil ranges 10 to 25 inches (.8 to 2.1 feet) and <br />extends to a depth greater than 5 feet. <br />Textures- Textures range loam to clay loam. One sample is clay (2W-5-99. <br />Clay content averages 32 percent and ranges 24 to 41 percent, sand content <br />averages 34 percent and ranges 27 to 43 percent. Silt content averages 34 <br />percent and ranges 30 to 45 percent. <br />Rock Fragments- Rock fragments average 20 percent and range 5 to 40 <br />percent. Rock Fragments are predominantly gravel and cobble size (2mm to <br />Page 9 of 11 <br />02/09/00 <br />