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coincide with rainfall events. Monitoring well MW-10 is located in highly fractured limestone, which was sett in place between two previously mined cuts. The rise in water ieve! may be attributable to the increased recharge, resulting from the increases permeability of the fractured rock in the vicinity of the well from these rainfall events. Ground Water Flow Based on previous investigations at the site it appeared that the ground water flow was in a southwesterly direction, parallel to the dip of the Codell sandstone. tt has also been observed that faulting across the site may cause adamning/mounding effect on the ground water. In order to better evaluate the ground water flow in this area, K-S recommended to Holnam that two (2) piezometers be installed in order to provide additional water level data. Piezometers, P-1 and P-2, were installed on May 31, 2000. After evaluating the results from the first two piezometers, a third piezometer, P3, was installed on October 12, 2000. The purpose of the third piezometer was to further evaluate the direction of groundwater flow on the south side of the PlE-SW trending fault identified on Figures 4 thru 7, Appendix B. An additional monitoring well (MW-10) was installed downgradient of the CKD landfills on the south side of the new conveyor system, on February 26, 2001. The Division of Minerals requested this well and Geology in their letter dated January 18, 2000 in order to collect ground water data closer to the downgradiem side of the CKD landfills. The installation of MW-10 was delayed until mining in that azea was complete. Piezometer P1 was also abandoned on February 26, 2001 to allow the backfilling with overburden material in that area. Figures 3 thru 7, Appendix B, represent the understanding of the ground water flow regime at the time of each of the five quarters of sampling. As one can see, the ground water flow direction and gradient were further characterized after the additional data from piezometers Pl, P2, P3 and MW-10 became available. It should be noted that the changes in the ground water flow regime depicted in figures 3 thru 7 are more attributable to the collection of additional data rather than to significant changes in the ground water flow. Based on the most recent data, it appears that the ground wafer on the north side of the fault is flowing generally south at an average gradient of 0.029. In addition, it appears that the groundwater flow on the south side of the fault is to the southwest at an average gradient of approximately 0.015. -This variation in flow direction may be a result of the effects of the fault and/or groundwater flow through the yet undisturbed limestone units to the east of monitoring well MW-10 and northeast of piezometer P3. The ground water gradient on the south side of the fault appears to slightly less than previously estimated (0.25-0.26) based on the new data from monitoring well MW-10. Ground Water Quality A summary of the ground water quality data is presented in Table 3. Tables 4, 5, and 6 have also been included to help evaluate the variations in water quality parameters over time for the individual wells (MW-7, -8 and -9). Laboratory reports from each of the five quarterly sampling events are included in Appendix C. Most of the constituent concentrations appear to be in the normal range given the geochemical nature t of the local geologic units. However, comparing the results of the May 2000 sampling event with other sampling results, there appeared to be an order-of-magnitude increase in the alkalinity and bicarbonate concentrations. The laboratory could find not errors when asked to review the raw data ' and calculations. However, it was possible that the chemist may have made a clerical error. The results of fire subsequent sampling events indicated that the alkalinity and bicarbonate concentrations were Ground Water Moeitoring 4 CopyrigW 2001 August 6.200r K-S & Company, Inc.