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Baseline Hydrologic Monitoring Plan — Hansen Project 34 <br />Diagrams of water quality major ions, describe gaining and losing reaches of Project streams, summarize <br />seasonal variations in flow and water quality, evaluate correlations between flow rates and water quality <br />parameters, and provide an inventory of seeps and springs in the Project area. <br />4. GROUNDWATER MONITORING <br />Groundwater is monitored to provide baseline data for water quality, water levels, hydraulic gradients, and <br />flow directions. This information will be used to document existing baseline conditions, support <br />engineering design, and evaluate potential impacts to water resources. The groundwater monitoring <br />program is also designed evaluate the hydraulic characteristics (hydraulic conductivity and gradient) of <br />water bearing strata. <br />Groundwater monitoring includes measurement of the depth to water in wells and the collection of samples <br />for water quality analysis on a quarterly basis. Existing monitoring wells, planned monitoring well <br />locations, the laboratory analytical suite, and procedures for well installation, permeability testing, water <br />level measurement, and sampling are described in the following sections and appendices. <br />4.1 Monitoring Well Locations <br />4.1.1 Existing Monitoring Well Locations <br />A total of 94 borings were drilled for hydrogeologic investigations of the Hansen and Picnic Tree deposits <br />and the proposed mill site from 1978 to 1980, and 92 of those borings were completed as wells. Locations <br />of these monitoring wells are shown in Figure 12. Historical water level and water quality data from these <br />wells have been compiled, field locations have been checked, and additional water level and water quality <br />data has been collected from several of these wells. <br />Seven of the existing Cyprus wells are monitored quarterly for water level and water quality (Table 12). <br />The wells were selected based on location, depth, hydrostratigraphic unit, and well integrity. All wells <br />were investigated by downhole camera to verify screened intervals and well integrity. Well permits were <br />filed with the Colorado Division of Water Resources to place these wells into active service. Surface <br />monuments were cemented in place with locking metal caps. Cumulative water quality data from 4th <br />Quarter 2011 to 3rd Quarter 2013 for six of the seven wells is provided in Appendix I. Well redevelopment <br />was performed at CMW21 -216 in summer 2013 before placing this well into service, and water quality data <br />will be available starting with the 4th Quarter 2013 monitoring event. <br />Table 12. Existing Active Groundwater Monitoring Wells for Baseline Characterization <br />near Hansen Deposit <br />Well ID Hydrostratigraphic Unit <br />MWC -21 -210 <br />Ttml <br />MWC -21 -219 <br />Ttc <br />MWC -21 -150 <br />Tep <br />MWC -21 -202 <br />Tep <br />MWC -109 <br />Qal <br />MWC -27 -286 Ttml & Ttc <br />MWC -21 -2163 Twm <br />Notes: <br />Qal = Quaternary Alluvium <br />3 Well CMW21 -216 was added to the routine monitoring program in 0 quarter 2013, after redevelopment. <br />4153A.140129 Whetstone Associates <br />