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Lightsey Well Inspection Record <br />Greeley, Colorado <br />Page 2 <br />4. Depth to well bottom measured at 47.17 feet below TOC; and <br />5. Pump type —centrifugal suction with drop pipe and foot valve. <br />A numerical groundwater model presented by AWES indicated that drawdown induced from Varra <br />dewatering operations in the vicinity of the well could be on the order of 20 feet. The existing depth <br />to water below the suction pump was measured at 7.5 feet below TOC. It is estimated that the <br />maximum practical dynamic suction lift at the well's elevation is on the order of 22 -24 feet. Adding <br />the maximum expected drawdown to the measured depth to water yields an elevation that <br />exceeds the pump's practical dynamic suction lift. <br />Assuming worst case, at a 20 water level change there would still be approximately 19.5 feet of <br />water column in the well. The current water volume needs were not indicated but based on past <br />experience light irrigation usage for a seven sprinkler head zone is estimated at 35 gallons per <br />minute. The expected drawdown using twice this volume is calculated at 11 feet, which would <br />leave 8 to 9 feet of water in the well during pumping. Predicted drawdowns calculations are <br />presented in Attachment B. <br />The well casing appeared to have significant iron carbonate or sulfate scaling at the time of the <br />inspection and well yields may be dramatically lower than calculated volumes. If a new pump <br />installation is required it may be advisable to jet the well prior to the pump installation. <br />If you have any questions regarding this letter or attachments, please contact me at 970 - 590 -3807. <br />Sincerely, <br />AWES, LLC <br />Joby L. Adams, P.G. <br />Pri n ci pal /Hyd rogeologist <br />�w�s 4809 Four Star Court, Fort Collins, CO 80524 970 -590 -3807 <br />