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Mr Harlan Knoll, R E H 5 December 30, 2005 Page 3 The blue line (higher line to the left and lower line to the right)on each graph is the difference between the total pressure measured in the well and the recorded barometric pressure. The pattern of minute variations (squxgglmess)of the groundwater elevation line on each well graph is not repetitive from day to day and has been labeled as "wind chatter"a very common cause of non-systematic variation in well water levels. The water level data shown in Figure 5 comprises 361 sets of potentiometric surface gradient and direction of gradient data for the well triangle formed by monitoring wells MW-1, MW-2, and MW-4 The potentiometric surface gradient is plotted as the lower graph of Figure 6 and the potentiometric surface gradient dtrectton, centered on map north, as the upper graph of Figure 6. Also shown on the gradient direction graph is the direction of the Municipal well from the center of the well triangle Thirteen of the 361 sets of potentiometric surface gradient and direction of gradient data for the well triangle formed by monitoring wells MW-1, MW-2, and MW4 point as far eastward as the municipal well's position with respect to the center of the monitored well triangle These thirteen easternmost potentiometric surface orientations do not form a pattern on Figure 6 indicative of a community water use pattern. The 361 sets of potentiometric surface orientation data for the well triangle formed by monitoring wells MW-1, MW-2, and MW-4 are plotted in Figure 7 as a `rose diagram' (a circular histogram)with two degree increments (e.g the central long bar includes data oriented from map north to 2 degrees east of map north) The direction data primarily points toward map north (Incidentally, this is parallel to the orientation of the adjacent drainage ditch and possibly buried storm drain line) A slight bimodality is present at north 6 to 8 degrees east, but no prominent orientation toward the Municipal well. The rotation of the potentiometric surface gradient direction from one data set to the following should reflect systematic variations. Thus is seen not to be the case in the upper graph of Figure 8 that shows the change in gradient direction with time The lower graph of Figure 8 similarly shows a lack of discernable patterns in the concurrent change of potentiometric surface gradient (the slope) The seeming randomness of the change to potentiometric surface orientation is minimized when shown as a scatter diagram (Figure 9) A supple best fit(regression) line through the scatter of change in potentiometric surface orientation data reveals that the opposite of what is expected within the drawdown cone around a pumping is observed When the potentiometric surface rotates to the east (generally toward the Municipal well)the gradient flattens and when the potentiometric surface rotates to the west (generally away from the Municipal well) the gradient steepens • H20GEOL A GROUNDWATER CONSULTANCY