REP39925

• Permit No: C1980005
• IBM Index Class Name: Report
• Doc Date: 2/28/1992
• Doc Name: 1991 AHR TEXT
• Annual Report Year: 1991
• Permit Index Doc Type: HYDROLOGY REPORT
• Media Type: D
• Archive: No

wash system, pumping water for dust suppression, and low runoff. Normal water levels
returned as the impoundment refilled in the spring. Water levels since the winter of
86/87 have not dropped as significantly during the winter months due to better management
of uaier usage from the Wadge Impoundment. In the past, water was continuously siphoned
from the Wadge Impoundment to the truck wash holding pond. Beginning in the winter of
87/88, the water is now pumped upon demand instead of continuously siphoned. Water
levels at Well 41-W have increased the past three years. This is likely a result of an
increase in the localized available recharge area of the Wadge coal as a result of
stripping topsoil upgradient of these cells, along with the exposed coal seam in the pit
upgradient of the wells, which allows eater collecting in the lower end of the pit to
recharge the coal seam. Water Levels at Well 42-N slowly declined beginning in the summer
of 1986 (likely due to dewatering caused by the adjacent pit), but have slightly increased
beginning in the fall of 7989, possibly due to bac kfilling of this pit and subsequent
resaturation. Well 79-W exhibits normal seasonal variations.
Wolf Creek Overburden/Wadge Underburden. Nel is 2-U, 7-WCO, and 37-WCO, all exhibit normal
seasonal variations. Well b-U has historically shown a general increase in eater level
until the summer of 1986, likely due to slow recharge from the adjacent Wadge Impoundment.
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as levels in the Wadge Impoundment decline from June through February each year. Water
levels at Well 6-U have shown a general decrease (approximately three feet) since the
summer of 1986. Water Levels at Well 11-U have slowly increased over the years, likely
due to slow recharge from the PeaCOCO pond immediately east of the well. In addition, a
leaky coupling was fixed at 11-U on 7/31/87, which caused an increase in pressure readings
for this flowing cell. Wells 8-U and 8P1-U have shown gradual declines in water levels
for the past several years, possibly due to disturbance of [he upgradient recharge area by
mining.
Wolf Creek Coal. Wells 10-WC, 14-WC, 15-WC and 37-WC all shooed normal seasonal
variations. A gradual decrease (approximately 24 feet) in water levels for Well 35-WC
since the spring of 1986 is likely due to a sl ou dewatering of the Wolf Creek coal due to
mining. This well is further doungradient and closer to the mining area than the
above-mentioned cells, which may explain why this well has shown a greater decline in
uaier level. The slight increase in water levels noted in the past year (two-foot rise,
summer of 1991) at this well is likely due to an increase in precipitation, indicating .
that The decrease in water levels in prior years may have also been in part due to
decreased precipitation for those years.
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