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~~~, II I I II I II I II IIII III ~ Doc Date:12/11/2001 SECTION 4.0 Regraded Spoil Laboratory Results • Trapper's approved Mining and Reclamation Permit (C-81-010), specifies annual sampling of recontoured spoils in the Ashmore and Flintlock pit areas. Section 2.7.2 of permit C-81-010 addresses the specifics of these requirements. In 1993, only a small portion of the Ashmore pit area was recontoured and sampled. Map 4-1 of this report illustrates the sample area. 4.1 Methods The 1993 mapping units were determined by the visual and textural difference of the surface spoils. Each sample of spoil was a composite from various areas within each mapping unit, from at least aone-foot depth of material. Two composite samples were taken in 1993. Again Map 4-1 presents these two mapping units along with the sample number, texture and year sampled. 4.2 Results Spoil samples were analyzed for the parameters outlined in Table 2.7.2a of Trapper's mining and reclama- tion permit. The 1993 laboratory analysis was performed by the Colorado State University Soil Testing • Laboratory. The lab results are presented on Table 41. Table 42 shows the suitability ratings of the 1993 samples as compared to the suitability ranges presented in permit Table 2.7-2a. Further comparison of the 1993 samples to historical topsoil and spoil samples are presented in Table 43. 4.3 Discussion and Recommendations The purpose for annual spoil sampling and analysis is to demonstrate that the recontoured surface spoil layer has acceptable physical and chemical properties to promote plant growth and successful reclamation. The 1993 data shows no problems and continues to indicate that Trapper is accomplishing this goal. With replacement of suitable topsoil, all recontoured spoils should provide an excellent medium for plant growth for any desirable postmine land use. [DMGV3REPT4] •