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Pagel 6 <br />Rule 6.4.7 Exhibit G - Water Information <br />19. Comment: Please submit a brief statement or plan showing how water from dewatering operation or from <br />runoff from disturbed areas, piled material and operating surfaces will be managed to protect against <br />pollution of either surface or groundwater (and, where applicable, control pollution in a manner that is <br />consistent with water quality discharge permits), both during and after the operation. <br />Response: Precision Excavating, Inc. (PEI) will start by building a 11x 2' high berm around the <br />entire perimeter of the pit boundary. This will keep all runoff and other pollutants contained within <br />the pit boundary and any stormwater will flow back into the pit rather than offsite. PEI will install <br />an irrigation ditch on the west side of permit area with up to 5 discharge points controlled by gate <br />valves for non-channelized land application dewatering. The onsite supervisor will monitor the <br />discharge points daily and adjust the discharge points accordingly to ensure that erosion is <br />minimized. Once enough material has been mined, temporary sediment ponds will be built to allow <br />sedimentation to settle prior to discharge. (Permanent sediment ponds will follow once there is <br />adequate space available.) The clean water will then be discharged into the Yampa River via a pipe <br />that will be installed. Testing of discharge water going into the river will occur bi-monthly to <br />comply with the sand and gravel discharge permit. Testing will include monitoring the level of total <br />dissolved solids (TDS), total suspended solids (TSS), PH levels, and a visual oil and grease to ensure <br />that there are not any contaminates being discharged. Also quarterly Discharge Monitoring Reports <br />will be sent to the Colorado Division of Public Health and Environment to track the levels of each of <br />the tests. <br />20. Comment: Please provide an estimate of the project water requirements including flow rates and annual <br />volumes for the development, mining, and reclamation phases of the project. <br />Response: The uses of water will include dewatering, dust control, product moisture loss, and <br />irrigation. The pumping rates will vary from 500 gpm to 1,500 gpm. The average annual volume <br />will be approximately 1,755 acre-feet. <br />21. Comment: Please indicate the projected amount from each of the sources of water to supply the project <br />water requirements for the mining operation and reclamation. <br />Response: All of the water to supply the project water requirements will come from one source, the <br />ground water and pond within the expansion area. <br />22. Comment: The applicant indicated the mine will discharge the dewatering water from Phases 1-5 as non- <br />channelized land application. Please provide documentation to the Division for review as to the proposed <br />maximum discharge rate and specifications as to how much water can be discharged without experiencing <br />erosion. <br />Response: The dewatering pump that will be used to discharge water through a non-channelized <br />land application will be pumping up to a maximum of 1500 gallons per minute (GPM). Through <br />previous experience with the original pit we have observed directly that installing an irrigation ditch <br />with little to no grade with multiple discharge points will keep erosion to a minimum. Furthermore, <br />the onsite supervisor will monitor the discharge points daily and adjust the discharge points <br />accordingly to ensure that erosion is minimized. <br />23. Comment: The applicant indicated the mine will discharge the dewatering water from Phase 6-13 from the <br />settling pond to Yampa River. If mine water is discharged into a ditch or other man-made structure, please <br />provide consent to discharge water into this structure. If water is discharged into a ditch that is unlined, it <br />may be prone to erosion if the discharge rates exceed the carrying capacity of the ditch. The applicant <br />should submit documentation to the Division for review as to the proposed maximum discharge rate and <br />specifications as to how much water can be discharged without experiencing erosion. <br />Response: The mine water from the settling pond will be piped to the Yampa River for direct <br />discharge into the river. The pipe will lay on the ground surface. The discharge will be monitored <br />by the onsite supervisor to ensure there is no erosion at the discharge point into the River and to <br />make adjustments if necessary. <br />24. Comment: Please affirmatively state that the Operator has acquired (or has applied for) a National <br />Pollutant Discharge Elimination System (NPDES) permit from the Water Quality Control Division at the <br />Colorado Department of Health for the amendment area and commit to providing a copy of the permit to <br />the Division.