2020-08-09_PERMIT FILE - M2020041

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2. Depth and Flow of Groundwater The groundwater levels measured in the on-site wells vary in depth over the course of the year. This is typical of alluvial aquifers of this type. The hydrographs (Figure 2 and Figure 3) show how the water table depth and elevation varied over the measurements in 2019 and 2020. Table 1 shows the specific measurements of groundwater depth taken in each well. 2019 was considered typical of the groundwater regime in this area. It was not a drought year, nor was it considered an out of character high water year. As is expected,the groundwater level of the aquifer is highest during the high flow period of the year in the early summer. As the runoff from spring snow melt tapers off and the amount of water in the alluvial system of the Blue River declines,the depth to groundwater increase. Table 1 - Groundwater Level from Monitoring Wells -. 0. 0• 13.8 14.5 15.9 19.2 14.74 5.5 5.2 9.7 16.4 9.98 17.8 17.5 23.8 28.8 19.91 11.1 11.3 14.3 17.6 12.06 6.56 6.8 9.0 13.7 7.7 - - - 13.8 6.5 16.0 9.0 19.6 13.3 - - - 13.4 4.2 14.0 5.0 Groundwater is deepest the farthest from infiltration sources or the river(GW-3) and shallowest near the wetlands in the northeast quadrant of the property (GW-2 & GW-5 and P 1 -P-6). The depth to groundwater near the wetland throughout the year is too great for the wetland to be sustained by alluvial groundwater(5.2 ft deep at the shallowest),but given the drainage path passing through the wetland, and that it is a low area for the property (see Map C-1), the wetland area clearly is a source of infiltration to the local alluvium. Surface water enters the wetland area through both seepage through the highway grade and via a culvert under the highway. Groundwater flow direction is roughly southeast to northwest,towards the Blue River. Peak Ranch Resource a R E S O U R C E July 2020 3 ■■UI E N . . N E. R I N G