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1 <br /> 115 <br /> drawdown of the piezometric surface induced by mining, the degree of hy- <br /> draulic communication between the mine and surface and near surface waters <br /> in the valley and the quantity of mine inflows. Aspects related primarily <br /> to water quality are contained in a separate section. <br /> Many years of experience and observation of geologic and ground- <br /> water conditions in the Allen Mine constitute a reliable analog that in- <br /> tegrates the variability of the lithologic and hydraulic properties that <br /> are so difficult and expensive to characterize by aquifer and core tests. <br /> This study sought to collect information that would permit a reliable <br /> extrapolation of the Allen experience to the Maxwell Mine, particularly <br /> with respect to mine inflows. It is believed that such an extrapolation <br /> is far superior to a mathematical model of inflows, provided that it can <br /> be established that the controlling geologic and hydraulic properties are <br /> reasonably similar at the two locations. <br /> Bedrock Studies <br /> As one step in establishing the similarity of the geologic and hy- <br /> draulic properties of the Raton formation at the two mines, cores and geo- <br /> physical logs from wells located immediately adjacent to the Maxell Mine, <br /> between the mines, and at the Allen Mine were examined. The locations of <br /> these wells are shown in Plate lA (map pocket). This examination pointed <br /> up� the extreme difficulty in establishing correlation between sandstone <br /> strata that might constitute aquifers. The geophysical logs from three <br /> bedrock wells (LA 218A, LA 221A, LA 264) are contained in the map pocket <br /> and, even in these relatively closely spaced wells , the lack of correlation <br /> is apparent. As described previously, these sandstones are channel deposits <br /> and poor correlation is to be expected. <br /> Samples of selected sandstone intervals were collected from the cores <br /> from wells 218, 221 , 198, 212, 200, Apache 20, and Apache 43 and the porosity <br /> and permeability of each sample was measured in the laboratory. Because <br /> of the lack of correlation, samples were collected from those intervals <br /> that appeared to be the most permeable. The raw data for these measurements <br /> are presented in Table lA in the Appendix, followed by a description of how <br /> � � the measurements were made. The results for 23 samples from the Raton <br />