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SECTION 4. Existing Conditions <br /> 4.1. Landscape Setting <br /> The survey area is located north and immediately adjacent to the Colorado River in an area <br /> historically used to mine gravel aggregate. Excavated areas have exposed the water table <br /> resulting in open water lacustrine bodies and the saline wetland in the southern portion of the <br /> survey area. The altered landscape has created excavated palustrine wetlands identified in the <br /> National Wetlands Inventory database. The FEMA Flood Insurance Rate Map or Flood Hazard <br /> Boundary Map designates the site as a high risk Zone AE(Figure 5, Appendix B). The site is <br /> mapped on the U.S. Geological Survey(USGS) Colorado National Monument and Grand <br /> Junction, Colorado 7.5 minute series quadrangle maps (USGS 2020). <br /> Soil types within the survey area(Figure 3) mapped by the Natural Resources Conservation <br /> Service (MRCS) are described in Table 3 (NRCS 2020) (Appendix B). <br /> 4.1.1. Current and Historic Land Uses <br /> The area surrounding the survey area consists of urban and rural areas including some industrial <br /> entities such as sand and gravel and manufacturing companies. The site has historically been <br /> used for open-pit gravel mining as designated on historic and current USGS maps. A walking <br /> and hiking trail is located on City of Grand Junction property along the river. Other recreational <br /> activities include boating and rafting. The closest residential building is outside the survey area <br /> to the north along 23'/4 Road, and is no longer inhabited. <br /> 4.1.2. Vegetation <br /> Wetland vegetation occurs as aquatic fringe in the littoral zone of the excavated palustrine <br /> wetlands. Lake water levels have recently increased based on the amount of submerged fringe <br /> wetland not yet showing water stress from the roots being inundated. Vegetation on the banks <br /> and interior of the saline wetland are affected by drought and anthropomorphic water inputs from <br /> active gravel pits mined in the surrounding area. Unvegetated areas within the interior of the <br /> saline wetland qualify as WOUS due to shallow groundwater conditions and presence of <br /> ordinary high water(OHW) indicators such a salt encrusted soils. <br /> Permanently and semi-permanently flooded water regimes associated with ponded water in <br /> excavated areas throughout the growing season bolsters the vigor of wetland vegetation fringing <br /> the lakes. The lack of perimeter fringe in some areas adjacent to standing water is from rising <br /> water levels inundating emergent and woody shrub aquatic vegetation,the latter mainly dead <br /> tamarisks fringing the south shore of the north lake. Fringe vegetation in the South Wilsea Drain <br /> was not included in this delineation. <br /> Wetland and upland plant species include a variety of forbs, shrubs, and trees mainly fringing <br /> current and former surface water bodies. Aquatic plants (OBL, FACW,FAC)were mainly <br /> represented by salt grass, cattail, artic rush, common reed,plantain weed,tamarisk, Russian <br /> olive, Fremont cottonwood, and narrowleaf willow. Upland plants include rubber rabbitbrush, <br /> 23'/4 Road Gravel Pit Page 3 of 8 December 2021 <br /> Aquatic Resource Delineation Report WestWater Engineering <br />