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Page 5 <br /> Mr. Eric Scott <br /> June 4th, 2021 <br /> (2) If the operation is expected to directly affect surface or groundwater systems,you shall: <br /> (a) Locate on the map (in Exhibit C) tributary water courses, wells, springs, stock water ponds, reservoirs, <br /> and ditches on the affected land and on adjacent lands where such structures may be affected by the <br /> proposed mining operations; There are pond features located south of the mine, and perhaps an irrigation <br /> ditch located immediately west of the mine, that are visible in aerial photos but not shown on the provided <br /> maps—please correct as needed. See attached Figure 2(Structures Within 200'). Note, however,that <br /> slurry wall on the subject mining land is expected to preclude any significant effect of operations on <br /> groundwater systems in the area. <br /> (b) Identify all known aquifers;and <br /> (c) Submit a brief statement or plan showing how water from dewatering operations or from runoff from <br /> disturbed areas,piled material and operating surfaces will be managed to protect against pollution of <br /> either surface or groundwater(and, where applicable, control pollution in a manner that is consistent with <br /> water quality discharge permits), both during and after the operation. <br /> (3) You must 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 /> This section specifically mentions evaporative loss from dewatering trenches, but does not clearly mention <br /> anywhere evaporative losses from the unlined sediment and fresh water ponds located in Phase 1. Surface <br /> areas of these ponds has also not been stated in the application or provided maps. Please correct as <br /> needed. Surface areas for the ponds is approximately 27 acres total. This section has been updated <br /> to include evaporative losses from the unlined sediment and freshwater ponds in Phase 1. See <br /> attached updated Exhibit G. <br /> (4) You must indicate the projected amount from each of the sources of water to supply the project water <br /> requirements for the mining operation and reclamation. <br /> (5) You must affirmatively state that the Operator/Applicant 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, if necessary. Please show the location of the CDPHE permitted discharge <br /> point discussed on the mining plan map. See attached updated Mining Plan Map with the locations of <br /> the 3 CDPHE discharge points located northwest of Cell 4, south west of Cell 4 and northwest of Cell <br /> 7. <br /> In Exhibit E, section 3.1.7 Groundwater, the applicant has committed to complying with the applicable <br /> standards for classified and unclassified groundwater. However, only one of these conditions will apply to <br /> the site, and no information has been provided as to how this will occur. Is the permit within a classified <br /> groundwater area or will the WQCC Rule 41 Tables 1-4 Interim Narrative Standards(INS)for Groundwater <br /> apply to this site? If INS applies(which is likely the case)no data showing ambient pre-mining groundwater <br /> conditions (levels or quality)has been provided, and no monitoring plan has been provided to detail how <br /> water levels and water quality will be observed and maintained through the life of the mine. The permit area <br /> is not located in a classified groundwater area and the Interim Narrative Standards for groundwater <br /> apply to the site. <br /> The only depiction of monitoring wells provided at this time appears to be on the Reclamation Maps, <br /> however there appear to be some large gaps between some of the locations shown. Is there any water <br /> level or chemistry data available for these wells?DRMS normally requires at least 5 quarters of water level <br /> monitoring prior to installation of slurry walls or dewatering activity to determine ambient conditions. <br /> Please submit a monitoring plan to detail where and how water levels and chemistry will be monitored to <br /> document that impacts to the prevailing hydrologic balance will be minimized and mitigated if necessary. <br /> These impacts may include off site impacts to existing water levels and water wells(mounding or shadowing <br /> due to slurry wall installation or unlined freshwater ponds) and potential corrective measures. The plan <br /> should also document how applicable standards for groundwater quality will be documented and <br /> maintained. See attached monitoring plan and updated Exhibit G.Water levels for wells 1-8 have <br />