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Land capability classification(irrigated):None specified <br /> Land capability classification(nonirrigated):8e <br /> Hydrologic Soil Group:D,Hydric soil rating:No <br /> Relevant Chemical Properties <br /> Soil reaction(pH):5.6-6.5 <br /> %Calcium Carbonate:0% <br /> The soil profile exposed along the pre-existing roadcut through the affected areas ranges from 0-18 inches <br /> thick and matches the physical characteristics described by NRCS. NRCS estimates the pH of both soil <br /> types to range between 5.6 and 6.5 and to have no Calcium Carbonate (CaCO3). <br /> To further characterize chemistry of surface materials, AMR collected two composite samples for <br /> laboratory analysis. The first was a composite of topsoil in the vicinity of the proposed primary mine <br /> entrance and the second was a composite of native bedrock beneath the topsoil in the same location. ACZ <br /> Laboratories, Inc. analyzed the samples using Synthetic Precipitate Leachate Procedure(SPLP), and Acid- <br /> Base-Accounting(ABA)parameters along with general chemistry(alkalinity, paste pH, etc.) and forms of <br /> sulfur. These analyses are used to determine the environmental fate of metals and acid forming potential <br /> of the materials sampled. The following is a brief description of the analytical methods and their <br /> applications: <br /> • SPLP metals analysis provides an indication if metals are mobile from a solid. These measures <br /> provide an indication of whether the metals can mobilize from the rock/soil and be transported to <br /> surface or groundwater. SPLP is a dilute acid digestion process that is commonly used to mimic <br /> acid rain. The resulting leachate generated from the test is used to characterize the `hazardous' <br /> character of a solid waste. It is a conservative method by which to estimate metals mobility. <br /> • ABA analysis provides an indication if the solids have an acidic or neutral character. The analysis <br /> determines acid generation potential(AP or AGP)as well as neutralization potential(NP). The net <br /> balance will measure whether the material is net neutral, basic or acidic(net neutralizing potential <br /> [NNP] =NP -AP) (Sobek et al., 1987). ABA interpretation guidelines are as follows: <br /> o If the NNP is greater than 20 kg/ton CaCO3,the material is non-acid producing. <br /> o If the NNP is less than-20 kg/ton CaCO3, the material is acid producing. <br /> o NNP values between-20 and 20 kg/ton CaCO3,the material can be either, albeit minimal. <br /> o Forms of sulfur indicate the type of sulfur present in the material and its reactivity. Organic <br /> (or residual) sulfur is non-reactive while pyritic is reactive. Sulfur as sulfate provides an <br /> indication of reactive potential but should be considered a bound form, and thus non- <br /> reactive. <br /> Results from the two composite samples collected by AMR are provided in Table 1 and summarized as <br /> follows: <br /> • The SPLP results from both samples indicate that very few elements are potentially soluble. Most <br /> elements (e.g. cadmium, copper, silver, zinc and others) yielded results below detectable <br /> concentrations. Only a few elements yielded detected concentrations in solution (e.g. aluminum, <br /> iron, lead and manganese). However,the detected values fell well below maximum concentration <br /> levels protective of human health (i.e. the maximum contaminant level [MCL] for lead is 0.015 <br /> mg/L which is greater than the measured concentrations of 0.0002 and 0.0005; there are no MCL <br /> values for aluminum, iron and manganese since their toxicity is considered low). <br /> Page 3 of 7 <br />