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FThe Zacharias soils have been formed on alluvial fans or low stream terraces. They are very deep and well drained. The surface layer is typically 14 to 19 inches thick. The subsoil ranges # from 16 to 34 inches thick. The effective rooting depth is 60 inches or more. The Zacharias gravelly clay loam, is designated Class IIs-4. Class 1I soils have moderate F, limitations that reduce the choice of plants, require special conservation practices, or both. The II; Zacharias gravel) where irrigated, is Y clay loam, g suited to row and field crops. Management considerations must include the high content of gravel. With appropriate crop selection, drip or Fsprinkler irrigation, and minimum or non-cultivation, these soils have demonstrated good to . excellent productivity. The Zacharias clay loam is designated as Class I. The Zacharias soils, where irrigated, are designated as prime farmland. The Cortina soil is designated as Class IIIs-4. This soil is not desi nated as orime farmland. Class III soils have severe limitations that reduce the choice of pI�ants, require special conservation practices, or both. The limitations are related to coarse soil texture and excessive gravel. This soil, however, demonstrates good productivity with appropriate management. FCONSERVATION OF SURFACE SOIL The uppermost layer of the soil profile, often called the surface soil, topsoil, or Ap horizon, is fill the part of the soil in which life is most abundant in such forms as plant roots, bacteria, fungi, and small animals. Being the remains of living organisms, soil organic matter has nutrient elements in its structure and thus becomes a small storehouse for such dements. It also has direct effects on the structure and tilth of the surface soil. It is important in differentiating the A horizons from subsoils. The conservation and re-use of excavated soils, however, is open to question because the removal of the soil will destroy its natural physical structure and profile. Stockpiling will result in the loss or significant reduction of the organic properties, including soil biota. These impacts are regarded as being more significant than loss of natural fertility which can be restored by fertilization. F. Identification of Surface Soil m Visual investigations and laboratory assays conducted by AGROXONDOR�during October 1994 indicate the uppermost foot (12 inches) of the Zacharias soils, generally designated as the Ap F. horizon, would qualify for separation as topsoil, although the depth of topsoil will probably vary across the site. See TABLE 1. Conservation of the surface overburden associated with the Cortina gravelly sandy loam and the Xerofluvents-Xerothents complex would provide no significant advantage for later reclamation and re-soiling use. 4 Report Rev.2-0620.95 AGRO ENVIRONMENTAL SERVICES • A Division of Condor Earth Technologies, Inc. f Condor