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JoEllen Turner <br />Borth Environmental Pollution Consuliina, LLC October 2, 2012 <br />set that included more data for the substitute soil. Confidence intervals cannot be used for <br />comparisons of means. The large confidence interval means that there is a lot of uncertainty <br />related to the sampling method. In addition, since the Barx Lift 34 soil could (in theory) have a <br />pH of 7.25 and the substitute soil could in theory have a pH value of 7.8 that would correspond <br />to a 5.5 times higher hydronium ion activity (acidity) for the Barx Lift 34 soil. Thus, the <br />substitute soil has the potential to result in a lower yield than the Barx subsoil. <br />7.2 Soil Salinity: <br />The major argument that Mr. Dejoia is trying to make in order to discount the high EC values <br />(EC up to 5 dSJm) determined for the substitute soil (a saline soil is considered to be any soil that <br />has an EC value higher than 4,0 dS /m) is that since he believes the soil is a " gypsiferous soil" <br />that it is acceptable to subtract 2 dSJm from the measured value (which would bring the <br />substitute into the non - saline category according to Ayers and Westcot, 1985). I do not agree <br />that the Morgan property comprises gypsiferous soil, as claimed by Mr. Dejoia. The presence of <br />gypsum in soil is not itself indicative of a gypsiferous soil. Gypsiferous soil is defined: <br />To identify gypsiferous soils, Soil Taxonomy requires the presence of one of two different <br />diagnostic horizons with high gypsum content: a gypsic horizon or a petrogypsic horizon. <br />Gypsic Horizon (from USDA, Keys to Soil Taxonomy, 11th edition, 2010): <br />The gypsic horizon is a horizon in which gypsum has accumulated or been transformed to a <br />significant extent. It typically occurs as a subsurface horizon, but it may occur at the <br />surface in some soils. <br />A gypsic horizon meets all of the following requirements: <br />1. Is 15 em or more thick; <br />970 - 864 -7682 p.16 <br />2. Is not cemented by gypsum, with or without other cementing agents; is cemented and the <br />cemented parts are less than 5 mm thick; or is cemented but, because of lateral <br />discontinuity, roots can penetrate along vertical fractures with a horizontal spacing of less <br />than 10 cm; <br />3. Is 5 percent or more (by weight) gypsum and has I percent or more (by volume) visible <br />secondary gypsum that has either accumulated or been transformed; and <br />4. Has a product of thickness, in cm, multiplied by the gypsum content (percent by weight) <br />of 150 or more. Thus, a horizon 30 cm thick that is 5 percent gypsum qualifies as a <br />gypsic horizon if it is I percent or more (by volume) visible gypsum and any <br />cementation is as described in 2 above. <br />Petrogypsic Horizon (from USDA, Keys to Soil Taxonomy, 11th edition, 2010): <br />15!Page <br />PLTF 002489 <br />