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Page 2 <br /> Mr. Mark Johnson <br /> January 31,2020 <br /> ➢ The Rural Ditch conveys irrigation water through mine site from west to east. A lateral from the <br /> Rural Ditch crosses the site immediately south of Cell 1. During the irrigation season,this ditch is <br /> likely a source of recharge to the water table. <br /> ➢ An unnamed drainage way traverses the west part of the site between Cells 2a and 2b before <br /> crossing north of cell 3. This drainage likely maintains groundwater levels at or above the water <br /> levels in the drainage. <br /> ➢ Five lined gravel ponds referred to as Ponds A, B, C, D, and E. These ponds likely cause <br /> groundwater mounding(higher water levels)on the upgradient side of the site(south and <br /> southwest sides)and groundwater shadowing (lower water levels)on the downgradient side of the <br /> site(northeast and north sides). These ponds have been lined for approximately 15 years. <br /> ➢ Irrigation: The site is located in an area of irrigated cropland. Applied irrigation that is not lost to <br /> evaporation and transpiration likely recharges the groundwater. <br /> ➢ Alluvial Wells: Other than the eight(8) monitoring wells drilled at the site for monitoring <br /> groundwater levels,there are only five(5) pumping wells permitted within 600 feet of the mine <br /> property. One of these wells is on-site at the former Vogl residence. Three(3)wells are located <br /> on the north side of Weld County Road 24 1/4. The last well is located southeast of the intersection <br /> of Weld County Roads 24 3/4 and 11 1/4. If pumping,groundwater will be drawn to the wells. <br /> Monthly groundwater level monitoring was performed from June, 2019 to December, 2019 at the eight(8) <br /> monitoring wells drilled at the site. Average depths to groundwater are presented in the following table: <br /> Average Depth to <br /> Groundwater,ft <br /> Well (June to <br /> December,2019) <br /> MW-3 17.43 <br /> MW-4 7.17 <br /> MW-5 5.69 <br /> MWNW 7.35 <br /> MWSE 3.09 <br /> V1 6.81 <br /> V2 10.42 <br /> V3 12.30 <br /> Mining Plan <br /> Five(5)lined cells have previously been mined or are in the process of being mined at the site. These lined <br /> cells are located south of Weld County Roads 24%and 26. The addition of the Vogl cells to the mine will <br /> result in two additional lined cells(2a and 3)and two additional unlined cells(1 and 2b)at the mine. All of <br /> the cells will be mined to bedrock. At the Vogl property, bedrock ranges from approximately 14 to 25 feet in <br /> borings drilled at the site. <br />