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<br />2.4.1 Areas to be Filled <br /> <br />Waterways that will need to be crossed along access route into Processing Site include two <br />sections of Monument Creek, a tail water drainage ditch, and an area of interior wetlands <br />(Appendix B, MP-1 and MP-2). The first Monument Creek crossing (farthest south) does not <br />contain wetland vegetation and requires fill in a 24' x 15' area (refer to Appendix B, DS-I for <br />crossing details). The second crossing, approximately 200 feet to the north, contains wetland <br />vegetation and requires fill in a 20' x 20' area. The other crossings that require fill are located on <br />the south edge of Processing Site (Appendix B, MP-1), a 20' x 40' section of the tail water ditch <br />will be crossed along with a 20' x 20' area of interior wetland. The Processing Site wetland <br />crossing will be temporary and not involve a culvert. Vegetation and soils excavated from this <br />wetland will be mitigated in Phase A, initiated early in the first mining phase after access road is <br />constructed. Total acreage of wetland materials disturbed by these crossings total about 0.05 <br />acres. <br />The tail water drainage ditch provides the hydrology for the 4.8 acres of wetlands that will remain <br />undisturbed. This drainage channel carries irrigation tail water west along the south site perimeter <br />where it discharges into the river in the southwest corner of site. Natural drainage features of the <br />site were altered by leveling and topographic control for operating the furrow irrigation system. <br />Resulting drainage system in the agricultural land drains water to the south where it collects in the <br />south tail water ditch resulting in associated fringe wetlands. <br />2.4.1.1 Types of Wetlands <br />Site wetlands can be classified as emergent, wet meadow, channel, and fringe or shore zone areas <br />adjacent to the river. These wetlands predominantly fall within the Palustrine System, Emergent <br />Wetland class, as defined by Cowardin and others (1979). These wetlands are characterized by a <br />number of grasses and grasslike plants including salt grass, cattails, and bulrushes. Wetland <br />hydrology is dominantly from groundwater discharge with some flowthrough components (i.e., <br />periodic recharge and discharge functions). <br />Wetland basins are not integrated with natural surface water channe]s/inlets resulting in a water <br />budget mainly comprised of groundwater and imgation water inputs, with minor contributions <br />from precipitation. Groundwater flow gradients are driven by local recharge areas probably <br />associated with seep flow infiltration and artificial sources from direct irrigation inputs and ditch <br />leakage. Seeps occur along the south site perimeter at the base of the topographic high areas, <br />generally in the draws. <br />Wetland water regime shows a range in pond permanency (ability to pond water) depending on <br />basin shape and site location. Wetlands with deeper water habitats (>1 ft depth) are permanent to <br />semipermanent while shallow wetlands are more seasonal. Deep water habitats are mainly limited <br />to basins altered by previous excavation. Stagnant water in these habitats are conducive for <br />2-6 <br />