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• maximum Cu value associated with the Raton Creek Mine overburden and bench materials was 6 ppm. Thus all of these materials appear to be suitable with respect to Cu levels. The suspect level of Pb is given by Schafer (1979) as 20 ppm. The maximum Pb value associated with these materials was 2.4 ppm, meaning that all of the overburden and bench materials are suitable with respect to Pb concentrations. Both Sutton et. al. (1981) and Schafer (1979) report that the suspect level of Hg is 0.5 ppm. Since all of the Raton Creek Mine overburden and bench materials were found to have Pb concentrations less than 0.01 ppm, these materials appear suitable with respect to this parameter. The suspect level for Zn is reported by Schafer (1979) to be 40 ppm. The maximum Zn concentration associated with the Raton Creek Mine overburden and bench materials was 16 ppm. Since all of the materials tested have Zn values below the suspect level these materials appear suitable with respect to Zn concentrations. RECOMMENDATIONS AND SUMMARY. This evaluation demonstrates that the Ratan Creek Mine overburden and bench materials that will be used as cover materials for the reclamation of the refuse pile are relatively clean with respect to their chemical and physical suitability as topsoil substitute and overburden root zone materials. Three potential limitations are evident from this evaluation: - Heavy clayey textures were observed - OC was exceeded in two samples • - High rack fragment contents were observed None of these limitations are of significant concern with respect to usage of these materials as refuse cover media because: - The clayey nature of the refuse cover materials, although marginal, is more suitable from a textural standpoint than the nature of the soil materials which will be used for reclamation of the area. - The two samples in which OC was exceeded comprise less than two percent of the material to be used for refuse cover. These zones are only 1.1 and 2.8 feet in thickness respectively, and will be sufficiently diluted during the removal and replacement process to eliminate this concern. Elevated rock fragment levels are characteristic of all soil materials in the area. Existing soils which are located on adjacent undisturbed areas and stockpiled soil materials have rock fragment contents higher than that of the potential cover materials. Since elevated rock fragment contents are typical of the area, this limitation should not adversely effect the utility of these materials as cover soil materials. It is recommended that a detailed evaluation of the refuse materials be conducted to determine whether or not four feet of cover are actually necessary. A preliminary evaluation of these materials, and existing . reclamation studies that have been conducted nearby by Colorado State University at Morley and Heston, Colorado on refuse materials much older than those found at the Raton Creek Mine, suggests that successful reclamation with a thick soil cover may not be necessary or desirable from an environmental or regulatory standpoint. It must be pointed out, that the 8