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

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Electrical Conductivity There does not appear to be a trend with the Electrical Conductivity (EC) levels within the soil profiles; except consistently the top horizon samples yielded EC levels below the threshold for Lift A/Mixed topsoil. All of the horizons sampled for each test pit were found to be below the threshold level for the Lift B and Bench 1 criteria. For TP01 the samples below 36cm had EC levels above the Lift A/Mixed topsoil threshold. For TP05, three samples yielded EC levels above the Lift A/Mixed topsoil levels (7 -24, 51 -140 and 140 to 190cm). Overall, the average EC levels were measured to be 2.74mmho /cm for all of the samples taken. Given the erratic nature of the EC levels throughout the profile, it would be difficult to set suitability criteria for this parameter based on the undisturbed soil test pits alone. However, in accordance with National Soil Survey Handbook Chapter 657.5, to be considered prime farmland, the soil must be managed so that in all horizons to a depth of 40 inches (100cm) or within the root zone (whichever is shallower), during part of each year, the electrical conductivity must be less than 4mmho /cm. Given this, it is possible portions of the undisturbed area have EC levels within the defined profile range that would disqualify the soil from prime farmland designation. Saturation Percentage All of the horizons sampled except for one had saturation percentages within the minimum and maximum threshold levels. For TP05, the bottom horizon (140 -190 cm) has a saturation percentage of 15.9% which is below the 25% minimum. However, this is the `only sample that was found to be below the criteria. Sodium Adsorption Ratio All of the horizons sampled had a Sodium Adsorption Ratio (SAR) below the threshold. Exchangeable Sodium Percentage (ESP) All of the horizons sampled had an Exchangeable Sodium Percentage (ESP) below the threshold established for Lift A material. Calcium Carbonate (CCE) % Calcium Carbonate appears to increase as the soil depth increases. All of the soil horizons sampled were found to have Calcium Carbonate (CCE) percentages below the threshold established for the Lift BBench 1 material. TP01 and TP02 only breached the CCE threshold for Lift A/Mixed topsoil material deep within the profile, at 150 -180cm for TP01 and 134 -164cm for TP02. Given the soil salvaging plan, it is unlikely a significant amount of material at these depths would be salvaged for reclamation. The majority of the upper horizons had CCE levels well below the threshold for Lift A/Mixed topsoil material. Rock Fragments All of the horizons sampled had a rock fragment percentages below the threshold. Texture Only one sample identified a horizon with a texture unsuitable for reclamation for all of the growth media types. The bottom horizon on TP02 (depth 134- 164cm) was classified as having a Clay "C" texture. All of the other horizons had acceptable textures as approved in the permit. Page 2 of 10