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Sl F ~ I ~ ~t7 Al l~ l `\ III IIIIII'II"II'If Doc Date:12/11/2001 <br />doc, n~~-=' Se~~,~~,-. y,o`~ 999 <br />SECTION 4.0 ~~ Regraded Spoil laboratory Results ~~ <br />• <br />Trapper's approved Mining and Reclamation Permit Application (C-81-010), specifies <br />recontoured spoil will be sampled annually for various chemical and physical properties to <br />ensure suitability as a plant growth medium. Section 2.7.2 addresses the parameters to be <br />sampled, sampling intensity and suitability ranges for those spoil parameters. TR-48, <br />approved in August, 1990, reduced the annual reporting requirements to regraded Ashmore <br />pit and problematic areas only. Trapper will sample and maintain all other spoil records on <br />site. Those records will be available to the CMLRD at all times. <br />4.1 Methods <br />Composite spoil samples (for all pits) were taken on approximately 50-ft to 100-ft centers <br />for each mapping unit. The 1990 mapping units were determined by visual and textural dif- <br />ference of the surface spoils. A sampling density of approximately one sample per 2.8 acres <br />of A pit reclaim area was accomplished. Each sample was a composite from at least one <br />foot of spoil material. The samples were analyzed for pH, EC, CaCOg, O.M., N03-N, P, IC, <br />Zn, Fe, Mn, Cu, Se, Ca, Mg, Na, K, SAR, % Saturation, texture, Total Hg, F, % Total S, and <br />the acid-base potential. If a large negative acid-base potential would have been found, then <br />additional analysis including pyritic Sulfur and SO4-S would be run for that sample. No <br />• samples exhibited a significant negative acid-base potential. The 1990 mapping units were <br />then transferred to the spoil history map (M4-1). Each unit on this map is identified as to <br />year sampled, texture, and lab analysis number. <br />4.2 Results <br />All 1990 spoil laboratory analyses were conducted by the Colorado State University Soil <br />Testing Laboratory. Ashmore pit spoil analysis is provided in Table 4-1. Comparisons <br />between the A pit laboratory results and the approved suitability ranges (Permit Table 2.7- <br />2a) indicate 1990 samples were all within allowable suitability ranges. Table 4-2 shows the <br />suitability ratings for the 1990 Ashmore pit spoils. <br />43 Discussion and Recommendations <br />As previously stated, the purpose of the routine annual spoil sampling and analysis is to <br />demonstrate that the replaced surface spoil layer has the acceptable physical and chemical <br />properties to promote plant growth and successful reclamation. The data strongly indicate <br />Trapper Mine has accomplished this goal within the 1990 sample areas. With the addition <br />of suitable topsoil, all spoils should provide an excellent medium for plant growth for any <br />desirable postmine land use. <br />• As per the second paragraph on page 2-361b of the approved permit, Trapper is notifying <br />the CMLRD of a potential problematic value in 1990's routine spoil sampling. That poten- <br />tial problem was not a result of the anticipated high Sodium or ESP values rather an atypical <br />