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Exhibit 42, Figures 58A and 58B. Plots of laboratory dissolved iron measurements for the Two Trout Creek <br />Sandstone wells are presented in Figures 58C and 58D and plots of field pH measurements are presented in Figures <br />• 58E and 58F. These plots of field conductivity, dissolved iron and pH measurements for the Two Trout Creek <br />Sandstone Wells do not indicate any trend which could be indicative of water quality impacts related to mining. <br />Dissolved iron concentrations show considerable variation, which may be due to sampling and sample preparation. <br />Iron and pH values are similar a[ the two wells. Conductivity levels in the Okie Plaza well are somewhat higher than <br />the levels in 9 Mine well as would be expected since the Okie Plaza well is deeper and further from the outcrop. <br />The declines in the piezometric levels in the Middle Sandstone observed in Figures 12 through 17, in Section 2.04-7, <br />Hydrology Information, are apparently related to dewatering and subsidence associated with Mines 5 and 6. The <br />declines in the levels in Wells 81-O1 and 83-O1 between 1988 and 1990 appear to have leveled off since the middle of <br />1990. Water levels in these two wells and in Well TR-7A measured during 1991 are similar to the levels measured in <br />1983 and 1984. The slight recovery from 1984 through 1988 is apparently the result of a shift in the location of <br />mining to an area further up dip. Water level fluctuations since 1983 are greater in Well 81-01 as compared to Wells <br />TR-7A and 83-O1 as would be expected since this well is closer to the location of mine dewatering. <br />The water levels in Well 83-02 show a different pattern. The water level decline of about I50 feet from 1987 to mid <br />1989 in Well 83-02 is determined to be related to mine dewatering as No. 5 Mine workings approached the location <br />of the well. The more abrupt 200 toot decline in water levels observed near the end of 1989 and beginning of 1990 is <br />thought to be a drawdown response due to subsidence as its location is only a few hundred feet horizontally from as F <br />seam longwall panel, which was mined in a similar time frame. <br />Wells TR-4 and 83-03 are located at greater distance horizontally from the active operations for Mines 5 and 6. <br />Water levels in Well TR-4 appear to be related to the fluctuations observed on all three of the down gradient Middle <br />Sandstone wells, 81-01, 83-O1, and 83-02. The water level decline in TR-4 prior to 1984 and the subsequent recovery <br />• up to 1988 closely parallels the trends observed in wells 81-O1 and 83-O1. The decline during the first part of 1991 <br />also parallels the trend in these two wells. However, the rapid decline during the last part of 1989 and the first part of <br />1990 appears to follow the trend observed in well 83-02 although the magnitude of decline is considerably less. <br />Well 83-03 is the Middle Sandstone monitoring well located furthest (more than I.5 miles) from active underground <br />operations for Mines 5 and 6. The water levels in Well 83-03 show pattern that requires further explanation given that <br />potentiometric levels at the well are under Flowing artesian conditions. The overall trend for this well from 1934 <br />through 1992 suggests a decline in potentiometric levels in this wel! of about 25 feet based on the linear regression <br />line included on Figure 17, Section 2.04-7, Hydrology Information. However, the occasional sharp decline followed <br />by rapid recovery which appear in the time plot are likely the result of errors in obtaining an accurate measurement of <br />equilibrium artesian pressures within the well. The long-term decline could be a pressure response due [o [he overall <br />drop in piezometric levels in the Middle Sandstone in the vicinity of Mines 5 and 6. On the other hand, there was no <br />apparent relationship between the Fluctuations observed in Well 83-03 with the fluctuations observed in other Middle <br />Sandstone wells due perhaps to possible pressure measurements Fluctuations and the further distance to the well. <br />Based upon the 1992 piezometric map (Map 13), the ground water gradient in the Middle Sandstone ranges from 120 <br />feet per mile to the southwest to 60 feet per mile to the southwest. The drop in piezometric levels in the Middle <br />Sandstone unit above the subsided longwall mine panels in the F and E coal seams has created a potentiometric <br />gradient to the south in the vicinity of the longwall panels. <br />The data for the three Middle Sandstone Wells, which are monitored for water quality show no adverse impact or <br />trend. Plots of field conductivity for these Middle Sandstone wells are presented in Figure 58B. Wells TR-7A and <br />TR-4 indicate slight reduction in concentrations of major ions over time. All three wells show reduction in <br />concentrations of iron, which shows considerable variation in concentrations. The general reduction in iron <br />concentrations may be the result of better purging of well pore volumes prior to sampling plus a switch to dissolve <br />concentration analysis. <br />MidTermResponse 2.05-41 ~~33 -~~"J~ ~Revisedl2%OS/61 <br />