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• percent slopes. The soils mapping unit description reports that the Louviers unit which composed 40 percent of this mapping unit complex, is classified as a "very channery clay loam". The textural modifier "very channery" denotes that the rock fragment content of these soils is greater than 35 percent but less than 60 percent rock fragments in the control section. This soil is obviously the most common soil on this site, yet of the 27 soil pits dug by the SCS in this area, only one pit has a notation suggesting rock fragments this high. This apparent discrepancy appears to be easily reconciled by the fact that the SCS pit notations do not consistently report gravel content. Field notes taken during the present sampling effort revealed that the colluvial derived soils (mapped by the SCS as being the Louviers Series) have approximately 50 percent surface rock with the rocks concentrated in the top foot of the soil. The A horizon zone (4-6 inches deep) contains approximately 15-25 percent cobbles and stones, while the C horizon (greater than 6 inches) contains approximately 10-15 percent cobbles and stones. There is very little gravel sized rock present in these materials. The shale derived soils (mapped by the SCS as being the Louviers Series) have approximately 50 percent surface stoniness. The A horizon (4-6 inches deep) contains approximately 15 percent rock fragments with essentially no rocks below the A horizon (6 inches). Rock fragments present on these soils appear to have been deposited by erosional processes from up the slope. The sandstone derived soils (mapped by the SCS as the Travessilla series) have approximately 30 percent surface stoniness. The A horizon (4-6 inches deep) • contains approximately 40 percent cobbles and stones with an almost equally high level of gravels. The C horizon materials (greater than 6 inches) generally contain 80 percent cobbles and stones with approximately equal parts gravel and fines. The Wyoming Guidelines for topsoil substitutes, suggest that all of these materials would have varying limitations as potential cover soil materials due to their rock fragment content. This comparison ignores the presently high rock fragment content of the "natural' soils of this area which have been stockpiled and which will be reapplied at the time of final reclamation. The potential cover materials have limitations with respect to rock fragment content and corresponding available water holding capacity. When compared to the surrounding undisturbed soils, these refuse cover materials possess more favorable characteristics with respect to rack fragment content and thus should pose no problems for such use. Since moisture is the most limiting factor influencing reclamation success in the west, the rock fragment content of these potential cover soil materials may be inferior to the refuse materials. It may well be that the refuse materials do not need four feet of cover. They may actually be better suited than the existing soil materials found in this area. Miscellaneous Parameters. Several of the parameters in the Colorado Guidelines do not have suspect levels listed in either the Wyoming or New Mexico Guidelines. Parameters included in this category include Cd, Cu, Pb, Hg, and Zn. No suggested suitability values for Fe, Mn and Total Combustible Solids were found in the technical literature so these parameters were not . addressed in the following evaluation. The suspect level for Cd is given by Schafer (]979) as being 1.0 ppm. All of the overburden and bench samples were found to have values below this level. Therefore, all of the materials tested appear to have suitable Cd values as potential reclamation materials. The suspect level for Cu is given by Sutton et. al. (1981) as 30 ppm. The