2012-08-24_GENERAL DOCUMENTS - C1981008 (2)

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4mmho /cm and the exchangeable sodium is less than 15 ". On average several of the currently stockpiled soils would not meet this 4mmhos/cm limit. However, based on the National Soil Survey Handbook, the suitability criteria for Lift B material and Bench 1 material should be lowered to 4mmhos/cm given that this material will be within the top 40 inches and/or within the root zone. Based on the lab data for Sample Pile B and the Bench 1 material sampled (TP06- TP08), the average EC was found to be 3.71 and 4.57mmho /cm respectively. Overall, the salvaged lift B material would be suitable to used for reclamation if the threshold was lowered to 4mmho /cm. The average EC for the Bench 1 material would indicate the majority of the material may not meet the suitability criteria if the threshold was lowered. However, it is likely the soil and subsoil could be managed through agricultural practices within the top 40 inches or within the root zone to reduce the EC level within tolerable levels within the revised suitability criteria. Comparison of 1998181; Order 1 Soil Survey Lab Results with 2011 Soil Sample Result from the Morgan Property Twenty four (24) soil tests pits were sampled in 1998 by hitermountain Resource Inventories, Inc. (1RI) throughout the permit area. At that time, lab samples were taken from three of these pits located on the Morgan property. Chemical analysis was conducted on the various horizons found within each of the test pits. Not all of the parameters were measured with the 1998 IRI samples as are identified on Table 2.05.4(2)(d) -lA Spoil and Soil Suitability Criteria (Morgan Prime Farmland). So a limited comparison can be made between the data. Table 1 below shows the average pH, Electrical Conductivity (EC), Saturation Percentage, Sodium Adsorption Ratio (SAR) and Lime (CCE %) content measured during the 2011 sampling of the undisturbed areas (TP -01 through TP -05; average of all horizons), the 2011 soil stockpile sampling (average of all samples within the piles) and the three test pits sampled during the 1998 IRI soil survey. Table 1. Average pH, Electrical Conductivity (EC), Saturation Percentage, Sodium Adsorption Ratio and Lime (CCE %) of three sample efforts on the Morgan property. The average pH measured is very similar between all of the sample events. Electrical Conductivity does vary between the sampling events. There does not appear to be a trend in EC levels verses soil depth or horizon based on the 1998 IRI soil survey results and the 2011 sampling of the remaining undisturbed area within the Morgan property. While on average it would appear EC levels increased within the property overtime, given the highly variable nature of the native soil in regards to EC, the 1998 IRI soil survey may not have been representative of the entire property. Also, EC levels are influenced by various environmental and human inputs. Depending on how the land was being managed in 1998 and 2011 could influence the lab result making it difficult to make a true comparison. The 1998 IRI soil survey does indicate a higher average saturation percentage SAR and lime content, however fewer samples were analyzed during the 1998 study than in 2011. It appears the currently approved soil suitability criteria listed on Table 2.05.4(2)(d) -lA of the permit were formulated based on previously approved criteria within the permit and consultation with the Page 9 of 10 H EC SatPercent Lime Sample Event SatPst mmhos /cm % SAR %CCE 2011 TPO1 -5 Undisturbed Area 7.42 2.74 36.08 0.22 7.48 2011 Soil Stockpiles 7.56 3.79 32.67 0.44 9.23 1998 IRI Order 1 Soil Survey 7.82 1.35 40.18 0.60 12.54 The average pH measured is very similar between all of the sample events. Electrical Conductivity does vary between the sampling events. There does not appear to be a trend in EC levels verses soil depth or horizon based on the 1998 IRI soil survey results and the 2011 sampling of the remaining undisturbed area within the Morgan property. While on average it would appear EC levels increased within the property overtime, given the highly variable nature of the native soil in regards to EC, the 1998 IRI soil survey may not have been representative of the entire property. Also, EC levels are influenced by various environmental and human inputs. Depending on how the land was being managed in 1998 and 2011 could influence the lab result making it difficult to make a true comparison. The 1998 IRI soil survey does indicate a higher average saturation percentage SAR and lime content, however fewer samples were analyzed during the 1998 study than in 2011. It appears the currently approved soil suitability criteria listed on Table 2.05.4(2)(d) -lA of the permit were formulated based on previously approved criteria within the permit and consultation with the Page 9 of 10