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<br />15 <br />t 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 1A in the Appendix, followed by a description of how <br />the measurements were made. The results for 23 samples from the Raton <br />I <br />