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

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each of these sites was recorded. The locations of these wetland test pits are depicted on Map 2.04.9 -1 - NRCS Soils Map. These data fail to suggest any potential for increased agricultural development of this area. Fourthly, in addition to the eight formal soil pits sampled considerable time in the actual stream channel area placing wetland boundary stakes and in surveying these locations. The incised drainage channel can be viewed as an excavated trench and the soils properties easily observed to determine whether or not these areas contain alluvial or colluvium materials. According to the OSM AVF Guideline, alluvial deposits are characterized by "gravel or well -sorted sand" (page A -2) or by "coarse- grained materials, such as gravel" (page A -4) or by "a heterogeneous mixture of sediment ranging from gravel to fine clay" (page A -4) with the "distinguishing features of alluvium are rounded particles and massive laying" page (A -14), which is often found in "all unconsolidated deposits" (page A -15). Conversely, colluvium is characterized as consisting of more "fine- grained" materials (page A -2), that are generally "unsorted" (page A -4), with the alluvial deposits typically being "flatter" while colluvial materials often "curve upward to meet the valley side" (page A -11). Colluvium often consists of more "angular grains" and is often "more thinly bedded" (page A -14). One of the methods recommended to distinguish between alluvial and colluvial materials is the occurrence of "distinctive rock types in the deposit which could have been transported to the valley fill only by the stream or slopewash processes" (page A -14). Application of these criteria clearly suggests that the vast majority of the "valley fill materials" located in Tuttle Draw consist of colluvium and not stream laid deposits of alluvium. Conversely, even if there are some alluvial deposits in Tuttle Draw, according to the OSM AVF Guideline "alluvial valley floors are not merely those valleys filled with alluvium." Fifthly, according to the criteria used by Hardaway and others (1977b), wherein they reported that "lowland areas more than 1.5 meters (on minor streams) ... in elevation above the water level in the channel ... were generally considered to be out of the alluvial valley floor" while "narrow streams incised more than 1.5 meters were generally assumed to indicate a water table too deep to maintain agricultural crops." Since the bottom of Tuttle Draw is almost always in excess of 1.5 meters below the adjacent floodplain elevation, by these criteria, these areas cannot be considered to be AVF's. Thus, based upon these site - specific data including vegetation, soils, geological source materials, and hydrology, these findings confirm the original findings in original NH1 Mine Permit application as well as all subsequent NH2 Mine submittals, that all of the lands within Section 36 are uplands as defined in the AVF's regulations. The NH1 permit findings wherein the DRMS has concluded that the minor amount of riparian fringe immediately adjacent to the flowing water, which is subirrigated is "not considered extensive enough to support agricultural development" is correct and that nothing has changed agriculturally along Tuttle Draw in the past 30 years to warrant a reconsideration of the negative presence of AVF's at this site. The DRMS has requested that WFC provide documentation on the "agricultural significance" of the wetland areas shown on Map 2.04.10 -1 - Permit Area Vegetation Map and which corresponds to the Grazingland - Subirrigated shown on Map 2.04.3 - Land Use Map. The intensive vegetation studies described in Section 2.04.10 - Vegetation Information, documented that the average forage production on the NHN Reclamation vegetation type was 845.0 pounds, Section 2.06.8 Page 6 April 2011