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TO CONCLUSION <br /> Civil Resources makes the following conclusions and recommendations based on the modeling: <br /> ➢ An underdrain or series of wells will be effective at minimizing the groundwater elevation rise south of the Site, <br /> and similarly the Gilcrest area,by removing water from the aquifer and rerouting it around the Site to the South <br /> Platte River via the unnamed slough west of the Monarch DENM Site. At total site buildout, including the <br /> Monarch DENM Site,the quantity of water to be piped to the river would be approximately 6.5 cubic feet per second. <br /> ➢ If the shadow affect to the north causes negative impacts to the wells north of the site(Schmidt and Owens <br /> wells)then a recharge drain or recharge pond could be constructed to the north of the site which would be <br /> effective at mitigating the shadow affect. <br /> ➢ The models and data presented in this report are based on eight(8)months of piezometer data collected at the <br /> site. Further groundwater monitoring of baseline conditions and after slurry wall 3,4, 5N construction will be <br /> necessary for designing the size and invert elevation for the underdrain or spacing for dewatering wells. <br /> ➢ Since groundwater is expected to rise(mound)south of the Site the mine operator should continue to monitor <br /> the existing monitoring wells in accordance with the groundwater monitoring and mitigation plan included with <br /> this report to catch any mounding or shadow effects at the Site before it become an issue to the surrounding <br /> properties. <br /> 8.0 BIBLIOGRAPHY <br /> Anderson, Mary P.,"Applied Groundwater Modelling,Academic Press Inc., San Diego CA, 1992. <br /> Bishop-Brogden Associates Inc. &JVA Consulting Engineers, "Dewatering Improvements Study for the Town of Gilcrest <br /> Colorado,"2016. <br /> Colton, 1978, "Geological Map of the Boulder, Fort Collins, and Greeley Area, Colorado,"U.S.G.S. Map 1-855-G. <br /> Das, Braja M., "Principles of Geotechnical Engineering, Fourth Edition,"PWS Publishing Company, Boston, <br /> Massachusetts, 1998. <br /> Fetter, C.W, "Applied Hydrogeology Third Edition,"Macmillan College Publishing Company, New York, 1994. <br /> U.S. Department of Agriculture, Soil Conservation Service, 1988, "Colorado Irrigation Guide." <br /> Waskom, 2013, "Report to the Colorado Legislature Concerning HB12-1278 Study of the South Platte River Alluvial <br /> Aquifer,"Colorado Water Institute. <br /> Groundwater Model Report—Section 20 Gravel Mine Site -13- August 2022 <br />