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Data Analysis; December 2011 Stockpile Sampling Program <br />For this review, I used the spreadsheet provided by KeyAg with the data from the stockpile sampling that <br />occurred at the New Horizon Mine, within the Morgan property, in December of 2011. This data was <br />analyzed and compared to the suitability thresholds approved in the permit on Table 2.05.4(2)(d) -lA. <br />Due to a lab error, the EC values measured originally were reported incorrectly when the data was first <br />submitted to the Division. Revised data was submitted to the Division. This analysis is based on the <br />updated data. <br />Based on a review of the suitability parameters, several of the threshold levels may need to be revised to <br />ensure the replaced topsoil and subsoil has the greatest potential to restore the property to prime farmland. <br />The Electrical Conductivity (EC) and Exchangeable Sodium Percentage (ESP) threshold set for Lift B <br />material and Bench 1 material should be revised. In accordance with the National Soil Survey Handbook <br />Chapter 657.5, to be considered a prime farmland soil, "the soil can be managed so that, in all horizons <br />within a depth of 40 inches (1 meter) or in the root zone if the root zone is less than 40 inches deep, <br />during part of each year the conductivity of the saturation is less than 4mmho /cm and the exchangeable <br />sodium is less than 15 ". Given this, the suitability criteria for Lift B and Bench 1 material should be <br />revised to 4mmhos /cm for EC and 15% for ESP given that a portion this material will be within the top <br />40 inches and/or within the root zone. <br />An analysis of each of the stockpiles is below. <br />Sample Pile A; Lift A <br />The average pH of the pile based on the multiple samples is 7.51. After charting the pH that was <br />measured, none of the samples are above or below the approved threshold. The average Electrical <br />Conductivity (EC) was 3.68mmho /cm for all of the samples taken within the stockpile. There were 67 <br />samples analyzed from this stockpile; of all the samples, eighteen yielded EC values above the <br />4mmho /cm threshold for this type of material (about 27% of the samples). Of these eighteen samples, <br />fifteen were taken from sample sites A -7 through,A -10. If these sample sites were located near each other <br />on the stockpile, it is logical the material piled in this portion of the stockpile was stripped from a single <br />area within the permit boundary where EC values were naturally higher. Also, it is noted the EC values <br />in sample sites A -7 to A -10 generally breach the threshold limit at depths between 10 feet to about 38 feet <br />within this portion of the pile. <br />The saturation percentage of each of the samples were found to be within the threshold limits. The <br />Sodium Adsorption Ratio (SAR) was found to be below the threshold limits. The Exchangeable Sodium <br />Percentage (ESP) was found to be well below the threshold. The Calcium Carbonate (CCE) averaged <br />7.88% within the stockpile. Only one sample was found to be above the threshold for CCE by 1.63 %, the <br />remainder of the samples were found to be below the approved threshold. There is currently not a rock <br />fragments percentage threshold for the Lift A or Mixed topsoil material, however the rock fragment levels <br />within this stockpile was well below the threshold for Lift B materials. <br />Based on the currently approved suitability criteria; the majority of Sample Pile A consisting of Lift A <br />topsoil material does meet the suitability criteria approved in the permit. A portion of the pile does not <br />meet the suitability criteria due to the EC values found above the approved threshold. As indicated above <br />only one sample yielded a CCE level above the threshold. <br />Page 3 of 10 <br />