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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 which is typical and then due to the dr,y sum- <br />mer the water level dropped 9.9 feet to 22.7 feet which is near <br />its historic loco level. <br />Piezometer P-2 showed a peak water level in March then by June it <br />dropped 5.0 feet to a level consistent with prior years records <br />for this piezometer. <br />Piezometer P-3 shocaed little variation in water level during the <br />year. <br />The piezometer at the top of the <br />tion during the year. Its water <br />and another 1.3 feet in 1989 and <br />when it dropped 1.3 feet. <br />bench, P-4, showed little varia- <br />level increased 2.3 feet in 1988 <br />then reversed the trend in 1990 <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 'L8.2 feet deep with s bentonite sesl at 8 feet. <br />It is designed to measure the water level in the coal waste <br />material. P-6 is 1'L .'? 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 caaste material are independent of each other. <br />Both piezometers showed an increase in water level during the <br />yesr which is of some concern. The water levels in the two ap- <br />pear to be independent. <br />Both the north and south underdrains had significantly less floc: <br />durinfi 1990 than 1989. The north underdrain's flow decreased <br />t'rom 0.07 to 0.001 acre-feet. The south underdrain's total flora <br />decreased from 0.32 to 0.01 acre-feet. The mass average conduc- <br />tivity for the north underdrain decreased and for the south un- <br />derdrain increased. These averages for 1990 were 2300 and x778 <br />compared 2873 and 460-1 during 1989 for the north and south un- <br />derdrain respectivel}-. The conductivity is measured in umhos/cm. <br />MINE WATER <br />The mine caas sesled in 1986. No information caas 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 hydroloeic impact from the reclaimed mine site is minimal. <br />No water from any of the sediment ponds was discharged during the <br />year. <br />-2- <br />