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Table 2.04-1. Selected Observed Soil Core Parameters <br />• <br /> <br />Soil Core <br /># Depth of Rooting <br />inches Depth to Mottles <br />inches Depth to Water. <br />inches <br />1 23 na Na <br />2 25 12 41 <br />3 8 na na <br />4 9 na na <br />5 48 na na <br />6 S0 na na <br />7 54+ na na <br />8 40+ na na <br />9 47 70 105 <br />10 19 na na <br />11 20 na na <br />12 20 na na ' <br />Maximum rooting depth at soil core #2 (Cumulic Cryaquoll) was observed into the seasonal high water table. <br />Soil mottling within the soil profile is a good indication of the depth of the seasonal high water table that can <br />fluctuate with the season and by yeaz. Enhanced vegetation growth and plant species adapted to mesic and <br />riparian sites was also evident adjacent to soil core #2. Unconsolidated stream-]aid sediments were observed at <br />25 inches and exhibited free water within these unconsolidated gravels and coarse sands. Similar soil <br />chazacteristics were observed in the small drainage channel bisecting the ventilation pad azea in Section 17 (Map <br />2S). <br />The maximum rooting depth at soil core #9 (Menbaz series) was observed to a depth of 47 inches with a <br />significant decline in roots noted at shallower depths due to calcareous root restricting horizons. Unconsolidated <br />• stream-laid sediments were observed below 105 inches and exhibited free water within these unconsolidated <br />gravels and coarse sands, however, no indicators of AVF soil characteristics were evident in this soil core within <br />the rooting zone. While this colluvial material may overlay water-bearing unconsolidated alluvial strata, these <br />colluvial materials aze at a sufficient depth and contain shallow, calcazeous root restricting horizons that prevent <br />any subirrigation potential. Reduced vegetation growth and production at this sampling site were evident from <br />the plant species that are more adapted to semi-arid, non-subimgated sites. The field survey observed a distinct <br />soil, vegetation, and topographic boundary between the AVF and the upland portion ofthe study area containing <br />the proposed ventilation shaft facility access road. <br />Soil core descriptions, surface vegetation, and topographic relief indicate that the existing AVF boundary (as <br />previously defined in Exhibits 7b, 42a, and 46) along Fish Creek in Section 11 should be relocated as shown on <br />Map 1S. Approximately 800 feet of proposed road corridor in Section 11 has been relocated upgradient <br />approximately 100 feet to follow an existing abandoned farmstead access road and avoid potential wetland soils <br />along the stock pond shoreline. The remaining 6,314 feet of access road corridor from the fenceline at the south <br />end of the stock pond to the shaft pad have no soil limitations. Soil coring and geologic stratigraphy strongly <br />suggest that the entire ventilation shaft pad is located on a suitable upland Winevada soil series formed over <br />fractured sandstone bedrock parent material. While the previous AVF boundary (shown in green on Map 1S) is <br />located within the southwest corner of the shafr pad, the revised AVF boundary (shown in red on Map 1 S) lies <br />outside of the proposed shafr pad location. Southern and western portions of the 500-foot buffer that overlay the <br />Fish Creek channel contain AVF and wetland soils (Map 1 S). No soil mapping activities were performed on the <br />west side of the railroad corridor within the 500-foot buffer azea since pad and shaft construction activities will <br />not cross the railroad tracks. As construction activities aze limited to the ventilation pad and northern and <br />eastern halves of the buffer area, no AVF or wetland soils will be affected. <br />• <br />PR06-07 2.04-50.2 11/07/06 <br />