REP11882

• Permit No: C1981044
• IBM Index Class Name: Report
• Doc Date: 4/16/1993
• Doc Name: 1992 AHR Text and water quality data tables
• From: CYPRUS EMPIRE CORP
• To: DMG
• Permit Index Doc Type: Hydrology Report 1992
• Media Type: D
• Archive: No

• Well 83-03 is the Middle Sandstone monitoring well located furthest
(more than 1.5 miles) from active underground operations for Mines
5 and 6. The overall trend from 1984 through 1992 suggests a
similar trend to the other Middle Sandstone wells. The long term
decline could be a pressure response due to the overall drop in
potentiometric levels in the Middle Sandstone in the vicinity of
Mines 5 and 6.
Monitoring results through year 1992 still show no apparent change
in the water levels in the Twentymile Sandstone that could be
attributable to mining activities. Water level plots indicate
essentially no change.
Based upon the 1992 piezometric map (Figure 14), the groundwater
gradient in the Middle Sandstone ranges from 130 feet per mile to
the southwest to 50 feet per mile to the southwest. The drop in
potentiometric levels in the Middle Sandstone unit above the
subsided longwall mine panels in the F and E coal seams has created
a potentiometric gradient to the south in the vicinity of the
longwall panels. A piezometric contour map of the Twentymile
Sandstone is presented in Figure 15. The map indicates that the
gradient is 220 feet per mile to the northwest and shows
essentially no change from 1991.
WATER QUALITY
• The water quality data for the two Trout Creek Sandstone Wells do
not indicate any water quality impacts related to mining. The
water quality data for the two Trout Creek Sandstone Wells are
summarized on Table 5 through 8. A plot of field conductivity
measurements is presented in Figure 16.
The data for the three Middle Sandstone Wells which are monitored
for water quality show no adverse impact or trend. Water quality
data are summarized in Tables 9 through 14. Plots of field
conductivity for these Middle Sandstone Wells are presented in
Figure 17. Wells TR-7A and TR-4 indicate slight reduction in
concentrations of major ions over time. All three wells show
reduction in concentrations of iron which shows considerable
variation in concentrations. The general reduction in iron
concentrations may be the result of better purging of well bore
volumes prior to sampling plus a switch to dissolved concentration
analysis.
The water quality data for the two Twentymile Sandstone Wells, No.
9 Mine Well and Well 259 show no adverse impact or trend. Water
quality data are summarized in Tables 16 through 18. Plots of
field conductivity over time are presented in Figure 18.
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