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~II III'llllllll 111 Doc Date:12/11/2001 SECTION 4.0 Regraded Spoil Laboratory Results As agreed in Trapper's approved Mining and Reclamation Permit Application (C-81- O10), recontoured spoil will be sampled annually for various chemical and physical prop- erties ensuring suitability as a plant growth medium. Section 2.7.2 of Trapper's permit addresses the parameters to be sampled, sampling intensity and suitability ranges for various spoil parameters. 4.1 Methods Composite samples were taken on approximately SO-ft to 100-ft centers for each map- 7 ping unit. Mapping units in 1989 were determined by visual and textural difference of the surface spoils. The sampling density of approximately one sample per five acres of reclaim area was accomplished. Each sample was a composite from at least one foot of spoil material. The samples were analyzed for pH, EC, CaC03, O.M., N03-N, P, K, Zn, Fe, Mn, Cu, Se, Ca, Mg, Na, K, SAR, % Saturation, texture, Total Hg, F, % Total S, and the acid-base potential. If a large negative acid-base potential would have been found, then additional analysis including pyritic Sulfur and SOq-S would be run for that sample. No samples exhibited a negative acid-base potential. The final mapping units were then transferred to the spoil history map, M4-1. Each delineation on this map was identified as to year sampled, te.Yture, and lab analysis number. • 4.2 Results Spoil laboratory analyses were conducted by the Colorado State University Soil Testing Laboratory and are provided in Table 4-1. Comparisons of the laboratory results and the suitability ranges for each sample parameter (Permit Table 2.7-2a) indicate all 1989 samples were within the allowable suitability ranges. 4.3 Discussion and Recommendations As previously stated, the purpose of spoil sampling and analysis is to demonstrate that the replaced surface spoil layer has the acceptable physical and chemical properties to promote plant growth and successful reclamation. The data strongly indicate Trapper Mine has accomplished this goal within the 1989 sample area. With the addition of suit- able topsoil, these regraded spoils provide an excellent medium for plant growth for any desirable postmine land use. Trapper therefore, proposes no additional spoil sampling or analysis be conducted in the 1989 sample areas. Additionally, Trapper proposes to eliminate the annual spoil sampling and analysis requirement for all pits (B, C, D & E) except Ashmore (A) pit. Collation of all spoil analyses from 1985 through 1989 shows all sampled parameters to be well within the suitability ranges for all parameters (Table 4.2 and Table 4.3). Additionally, historic overburden core sampling and analysis have shown no potential problem areas in any pit other than Ashmore. Since overburden drilling analysis and spoil sampling have shown suspect concentrations for ESP values in A pit, the approved annual spoil analysis pro- gram shall be maintained for that pit.