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The agriculturalsuitability assessment of the property is primarily based on the Soil Survey of San <br /> Joaquin County. Soil types are classified in terms of"Land Capability"with a rating scale known <br /> as the Storie Index Rating. The Land Capability rating indicates very severe limitations for the <br /> subject property soil under non-irrigated conditions and moderate limitations under irrigated <br /> conditions. Limitations are due to a"stony" classification that impedes typical agricultural <br /> practices such as tillage, planting, irrigation patterns, and surface/subsurface drainage. <br /> The Storie Index Rating for the Zacharias soil type has relatively high ratings, with an Index of 66 <br /> and a Grade of 2. Both ratings signify the soil is acceptable for agricultural production. However, <br /> it is my opinion the subject property soils are extremely marginal for agricultural production for the <br /> following reasons: <br /> • Due to the high clay content of the surface soils, the property surface soils are extremely <br /> hard and brittle when dry. Low organic matter content makes the tilth of the soil <br /> substandard. <br /> • Tillage of the soils below the six-inch depth would most Iikely cause accelerated wear on <br /> any type of implement due to the heavy gravel content. In addition, tillage would possibly <br /> bring gravel and cobble to the land surface. <br /> • Irrigation water chemistry would have to be optimum to for irrigation of shallow rooted <br /> crops. Any sodium concentration within the water would cause the clay lattices of the soil <br /> to bind-up and render the soil impermeable. This can be counteracted with gypsum, but the <br /> beneficial effects of this amendment are only temporary. <br /> • Groundwater pumping from the massive gravel plant to the west may cause groundwater <br /> depth and directional flow fluctuations that would have to be accounted for in an irrigation <br /> well. <br /> • If row crops were grown and furrow irrigated, tailwater would have to be managed <br /> accordingly. <br /> • The subsurface soil characteristics from the drilling procedures and percolation test results <br /> indicate the hydraulic conductivity of the soils at deeper depths is marginal, at best. This <br /> would prevent percolating irrigation water to provide adequate irrigation water to the root <br /> zone of a tree crop. <br /> • It is theorized that spoils excavated during the construction of the adjacent Delta-Mendota <br /> Canal were placed on the subject property. Overburden pressures, along with the gravel <br /> and cobble acting as binder agents have acted to compress and solidify the spoils, which is <br /> what was encountered during the drilling process and contributed to auger refusal. <br /> Regardless, from direct observations, the soil structures underlying the subject property <br /> reveal them to be highly deleterious for optimum root growth of tree crops. <br /> • Specific agricultural irrigation suitability chemistry was conducted on a water sample <br /> obtained from the on-site well. Constituents tested regarding irrigation suitability include <br /> sodium, bicarbonate, chloride, pH, nitrate, boron, TDS, Total Hardness and Adjusted <br /> Sodium Adsorption Ratio (SARadj). Comparing all of these constituents and parameters, it <br /> is determined that the water is moderately restrictive for agricultural irrigation for most <br /> agricultural crops. This is based upon Table 2-5: Guidelines for Interpretation of Water <br /> Quality for Irrigation in the Western Fertilizer Handbook. <br /> 4 <br /> Chesney Consulting <br />