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The elongate geometry of the pit affects the shape of the overburden drawdown contours at • short distances; at greater distances, the contours are circular, as if the pit itself were circular. The overburden drawdown contours do not intersect any of the boundaries, therefore no impact to the San Miguel River from drawdown in the deeper part of the overburden is predicted. Shallow aquifer flow into Tuttle and Calamity Draws in the vt cinity of the pit will be decreased, but will be offset by pumpage from the pit. The drawdown for the coal simulation was 8.0 ft during year 1, 5.8 ft during year 2, 6.0 ft during year 3, 7.3 ft during year 4, and 8.0 ft during year 5. The resulting coal drawdowns after each year are shown in Figures 17-9 through 17-13. Some boundary effects are evident on the coal drawdown plots as the drawdown eventually intercepted all four boundaries, including the San Miguel River. Table 17-4 presents the simulated annual inflow for the overburden and coal simulations. The greatest inflow is during the fifth year, when the pit is the deepest. These rates represent an average for the year. The simulated rates are greater in the beginning of each simulation year because of the instantaneously imposed change in pit depth. Because the pit will not be instantaneously deepened, the average rates are more realistic than the slightly higher peak rates. During the last time step of each year, little change in water levels occurred in the simulations. The approximate steady-state nature also can be seen by comparing the inflow rates for the first two years (Table 17-4). These rates are very similar. Attachment 16-1, Tab 16 and, in particular, Table 10 within Attachment 16-1 address the ground and surface water rights in the immediate vicinity of the Nucla and Nucla East mining areas that could potentially be affected by pit inflow drawdowns. The water-righted wells are completed in deeper aquifer units and should not be significantly affected by pit induced drawdowns in the overburden. Peabody will attempt to secure permission to monitor water levels in righted wells W-9 and W-41 (the two shallowest completions) and is proposing to install up to five overburden piezometers in the immediate vicinity of the Nucla East mining area to help insure that the drawdown projections are reasonably accurate and that the local water rights are protected. i Impacts to the local ground water users should be insignificant. Should the proposed 17-20 Revised 04/11/88