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<br /> <br />The Division correctly points out that the monitoring wells did not detect cyanide <br />during the sampling events when these wells were constructed. The field <br />parameters of pH, specific conductance and temperature were recorded from each <br />sample obtained from the monitoring wells, and these data are presented in Table <br />1. <br />BMR is unclear on the Division's comment regarding how representative the <br />samples were of the Santa Fe aquifer. Assuming the Division's crnnment relates <br />to whether the field parameters stabilized prior to sampling, BMR did meet the <br />QA/QC protocol for representativeness. <br />The elevated pH at well M-13 is thought to be grout infiltration in that M-13, to <br />be completed in the same horizon as M-9, was plugged back and, due to the low <br />permeability at this site, it is taking extra time to purge the grout that may (rave <br />mixed with the water in the zone being monitored. <br />4. Any field parameters, e.g. Ec, pH, temperature, recorded for the water samples <br />secured far this drilling project should be provided. <br />RESPONSE: These values are provided in the attached Table 1. <br />COMMENTS BY SCOTT G. MEFFORD <br />1. (partial) [TJhe aquifer tests were not conducted for a long enough duration to <br />allow drawdown to occur in the other test wells, and no nrnnitnr wells were <br />installed. Consequently, no values for the storage coefficient of the aquifer can <br />be calculated. <br />RESPONSE: Given the extremely low aquifer transmissivity and hydraulic conductivity, <br />pumping of these wells will reach asteady-state in a very short period of time, <br />making the value of the storage coefficient of the aquifer a moot pint. The lack <br />of an actual storage coefficient value, therefore, has no impact on the evaluation <br />of the adequacy of the currently-installed monitoring wells to detect contaminants <br />in the aquifer. <br />2. (partial) It is our understanding drat one purpose of the current study was to <br />develop dte necessary data and design a growtdwatcr corvainnrcnA systcrn below <br />the tailings facilities. Since no value for the storage coefficient of the aquifer was <br />established, we cannot model well interference effects or design an effective <br />groundwater containment system. No such design is artenrpred in the dncnnrent. <br />-6- <br />