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SGM reviewed the Soil Survey Geographic Database (SSURGO) which confirmed the <br /> presence of four soil types within the Affected Lands (as described in Section 10). The <br /> mapped soil unit boundaries were found to be roughly accurate, although soil texture did <br /> vary widely, likely as a result of the combination of past agricultural treatments and historic <br /> flood deposition/scouring events. Vegetation types do not correspond closely to the mapped <br /> soil types, as a result of ongoing disturbance from agricultural activities. <br /> • Halaquepts, nearly level: This soil type dominates the western half of the property and <br /> extends into a small portion of the Affected Lands. It is a saline soil type that <br /> experiences both a seasonal high water table and a period in which evapotranspiration <br /> brings salts to the soil surface. It is classed as moderately to strongly saline, and is a <br /> hydric soil type. The halaquepts on the site are likely derived from the local loams and <br /> sandy loams, but have been modified by the high water table and evapotranspirative <br /> demand. The reported alkalinity of this soil is Moderately to Strongly Alkaline. This soil <br /> type supports predominantly a sparse Russian olive woodland with sparse shrub cover <br /> and thick herbaceous groundcover of mesic species. Salt-tolerant species such as <br /> greasewood, alkali sacaton, and inland saltgrass dominate. <br /> • Wann sandy loam, 1-3% slopes: This soil type surrounds the tailwater ditch within the <br /> Affected Lands. It is a poorly-drained alluvial deposit that is non-saline to slightly saline. <br /> It is similar to the halaquepts, but does not experience the seasonal high water table and <br /> evapotranspiration necessary to concentrate salts at the soil surface. It is a hydric soil <br /> type. It supports almost entirely pasture vegetation with limited shrub occurrence. This is <br /> likely the result of the excavation and ongoing maintenance of the ditch, and the fact that <br /> much of the surface soil incorporates gravel/cobble sidecast derived from the excavation <br /> of the ditch. <br /> • Kim loam, 3-6% slopes: This soil type is limited to the northeast corner of the Affected <br /> Lands. It is also an alluvial deposit, but is well drained and does not have a high water <br /> table. Salinity is negligible and it is not a hydric soil type. It supports primarily pasture <br /> vegetation with small components of Russian olive woodland in topographical swales. <br /> • Olney loam, 1-3% slopes: This soil type is limited to the southeast corner of the <br /> Affected Lands. It is very similar to Kim loam, being an alluvial deposit that is well <br /> drained and does not have a high water table. It may be very slightly saline. It is not a <br /> hydric soil type. It supports primarily pasture vegetation with small components of <br /> Russian olive woodland where agricultural waters have been discharged in the past. <br /> 11.2 Post Vegetation Land Use <br /> After reclamation, land use in the non-pond areas would revert to mesic non-irrigated wildlife <br /> forage habitat, which is its current use. See Figure 14, Exhibit E1, and Figure 15, Exhibit <br /> E2. <br /> The limited existing woody riparian vegetation on the Affected Lands would be entirely <br /> eliminated. Shrubby ruderal species such as rabbitbrush and greasewood would re- <br /> establish quickly in the upland reclamation areas. There are no native riparian trees <br /> (cottonwoods) within the Affected Lands. <br /> 63 <br />