2012-06-20_PERMIT FILE - C2010089A (13)

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As directed by the DRMS, Map 2.06.8 -1 has been added to show the "Valley Fill Areas" including the boundary of the proposed NHN Mine Permit Area. However, as discussed earlier, this map cannot be interpreted to suggest that the "Valley Fill Areas " delineated on this map correspond to AVF's as suggested by the DRMS and that many of these areas contain colluvial materials and thus do not satisfy the definition of an AVF. The extent of all areas which have historically been flood irrigated is identified on Map 2.04.3 -1 - Land Use Map. The extent of all areas corresponding to different agricultural activities, including flood irrigated lands, pasture lands, undeveloped rangelands are found shown on Map 2.04.3 -1 - Land Use Map and are addressed in the discussion of land use found in Section 2.04.3. Detailed site specific measurements of vegetation productivity of these corresponding land uses by soils map unit are found in Section 2.04.9 and in the discussion of vegetation found in Section 2.04.10. As discussed in these sections, there has never been any historic flood irrigation in the Tuttle Draw equipment corridor crossing area. With respect to the potential for subirrigation in the floodplain of the areas along Tuttle Draw, it can be concluded that more detailed vegetation information and wetland mapping of these areas, obtained in connection with the environmental studies performed in connection with this permit application have better addressed the potential for agricultural development of this site. The vegetation characteristics of this site are found in the narrative found in Section 2.04.10 - Vegetation Information and on Map 2.04.10 -1 Vegetation Map. A preliminary discussion of the wetland information is found in the discussion of wetlands found in 2.05.6(2) and on Map 2.05.6(2) -1 Wetland Map. With respect to the potential of future agricultural development in the Tuttle Draw area, the following discussion is appropriate. According to the report by Hardaway and others (1977b), the areas along the floodplain in the bottom of Tuttle Draw would not meet the current AVF criteria for a number of reasons. Firstly, many of the floodplain areas are less then 15 meters wide, making it impracticable to develop such areas. These authors conclude that "these narrower valleys are not essential to agricultural operations." Since the bottom of Tuttle Draw contains a very narrow riparian fringe, it is WFC's opinion that this area would not meet the "size criteria " of an AVF found at 2.06.8(3) as it would be operationally unrealistic and economically impossible to develop and farm such a small, narrow strip of land. Secondly, as are documented on Map 2.04.10 -1 Vegetation Map, most of this area is dominated by Basin Big Sagebrush and Greasewood, which according to Hardaway and others (1977b), such plant communities are typically considered to be "indicators of deeper ground water levels and thus be located outside the alluvial valley floor." As such, these areas cannot be considered to be AVF's. Thirdly, in connection with the wetland mapping of the proposed equipment corridor alignments across Tuttle Draw shown on Map 2.05.6(2) -1 - Wetland Map, a total of five field days were spending working on this specific location. In this effort, a total of seven wetland sample plots, (EQCP -14, EQCP -15, EQCP -16, EQCP -17, EQCP -18, EQCP -19 and EQCP -20), wherein soil pits were dug approximately 20 inches deep- and, soil textures, the present of mottling, the evidence of flooding or an elevated groundwater table as well as the vegetation characteristics of Section 2.06.8 Page 5 April 2011