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<br />and/or concerns: <br /> <br />The accuracy of slug tests are highly dependent upon having a well that is fully <br />developed. Incomplete development can lead to low and very misleading values <br />of hydraulic conductivity. Since there were problems in the development of the <br />Santa Fe wells, we have concems over the accuracy of the slug tests. <br />On table A-3, the comments concerning well SF-2 indicate "Could not be tested <br />since static water level had not stabilized.", yet there is a hydraulic conductivity <br />assigned [o this well. What's going on here? Was [he well tested? Is the value <br />given any good? If tested, was the test biased by the natural recovery the well <br />was undergoing? Is the value from this well used in the calculation of geometric <br />mean hydraulic conductivity presented on Table 3-1 of the main text? <br />Wells SF-1, 2, and 4 apparently were tested. The hydraulic conductivities varied <br />by an order of magnitude, even in this small sample. I'm not sure tlhere is any real <br />significance to the geometric mean hydraulic conductivity quoted on Table 3-1 of <br />the main text when we have such a small sample and such a significant variability. <br />The highest permeability, and highest water level in the Santa Fe seem to be in the <br />area overlain by the flow window in [he alluvium. Are [he alluvium and Santa Fe <br />hydraulically connected in this area? <br />Table A-3 indicates well SF-5 is dry. Again, this does not seem consistent with <br />the development discussion. <br />General Comments <br />MLRB directed construction of an additional Santa Fe well. This well was <br />originally mis-located and drilled at site SF-4, but another well was subsequently <br />completed at the designated site, (site SF-5). No water level data, water quality <br />data, or aquifer testing data from well SF-5 is included in this report. This is <br />apparently due to a timing problem, however, a supplement to [his report should <br />be issued presenting the data from the SF-5 well and describing how the findings <br />may impact any conclusions in [he report. <br />It appears from the work completed that the permeability of [he Rito Seco <br />alluvium is significantly greater than that of the Santa Fe, and the greatest flux <br />from the pit is coming through the alluvium. While we would concur with this <br />basic assessment, we are concerned that the water balance suggests there could be <br />some water unaccounted for and the aquifer testing may have some problems. As <br />such, we cannot quantify the amount of water entering the Santa Fe. <br />Consequently, we believe any remedial program should include monitoring of <br />water levels and quality in the Santa Fe well network (wells SF-1 through SF-5) <br />