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GROUND WATER <br /> The piezometers on the mine bench were monitored quarterly for <br /> water level . Graphs are included with this report which show <br /> historical water levels of the piezometers . The water level in <br /> P-1 peaked in March 1989 to its highest level ever. Since March <br /> the water level in P-1 has dropped 16 .8 feet'. During the last <br /> three years P-1 has shown wide seasonal variations with the peak <br /> water level occurring in March and the low water level occurring <br /> in December. <br /> Piezometer P-2 showed little variation and little water which is <br /> consistent with prior years records for this piezometer. <br /> Piezometer P-3 showed a peak water level in March then it vir- <br /> tually dried up by December. Its water level dropped from -34 . 8 <br /> to -49 . 3 a total of 14 . 5 feet. <br /> The piezometer at the top of the bench, P-4 , showed little varia- <br /> tion during the year. Its water level increased 2 . 3 feet in 1988 <br /> and another 1 . 3 feet in 1989 . <br /> On October 12 , 1989 , piezometers P-5 and P-6 were installed on <br /> the face of the bench in the area of the 1989 cover material <br /> slump. P-5 is 28 .2 feet deep with a bentonite seal at 8 feet . <br /> It is designed to measure the water level in the coal waste <br /> material . P-6 is 12 . 2 feet deep with a bentonite seal at 2 feet <br /> on up to the surface. It is designed to measure the water level <br /> in the cover material . The piezometers are close enough together <br /> so it can be determined if the water level in the cover material <br /> and the coal waste material are independent of each other. As- <br /> built drawings of P-5 and P-6 are included with this report. <br /> The north underdrain had less flow during 1989 than 1988. The <br /> north underdrain' s flow decreased from 0. 10 to 0. 07 acre-feet. <br /> The south underdrain's total flow increased from 0. 27 to 0 . 32 <br /> acre-feet . The mass average conductivity for both underdrains <br /> was higher than last year. These averages for 1989 were 2873 and <br /> 4604 compared to 1988 ' s 2304 and 4468 for the north and south <br /> underdrain respectively. The conductivity is measured in <br /> umhos/cm. <br /> MINE WATER <br /> The mine was sealed in 1986 . No information was collected during <br /> 1989 . <br /> CONSUMPTIVE USE OF WATER <br /> There was no consumptive use of water during the year. <br /> HYDROLOGIC IMPACTS <br /> The hydrologic impact from the reclaimed mine site is minimal . <br /> The discharge from the pond no . 5 was the only direct discharge <br /> into hubbard creek from the mine site and it only totaled 0 . 45 <br /> acre-feet for the entire year. <br /> -2- <br />