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Blue Ribbon Mine - AHR Page 2 <br />GROUND WATER <br />Piezometers <br />The piezometers on the mine bench were monitored quarterly for water level. Graphs <br />are included with this report which show historical water levels of the piezometers. <br />The water level in P-1 peaked in the 1St quarter and then the water level dropped 13.7 <br />feet to 16.4 feet in 4th quarter. <br />Piezometer P-2 showed a peak water level in the 1 st quarter and then by the 4th quarter <br />it dropped 22.5 feet to 37.5 feet in 4th quarter. <br />Piezometer P-3 showed a peak water level in the 1 st quarter and then by 4th quarter it <br />dropped 26.1 feet to 35.6 feet in 3rd quarter. The water level was up slightly in the 4th <br />quarter. <br />The piezometer at the top of the bench, P-4, showed a slight upward trend during the <br />year. <br />The water level in P-5 averaged 18.2 feet deep during the year. At the end of the year <br />the water level in P-5 was 23.5 feet deep, deeper than prior years. <br />Monitoring of piezometer P-6 has been discontinued because it was destroyed by the <br />1993 bench cover material slump. <br />Underdrains <br />There was a small flow in the north underdrain during the year. The middle and south <br />underdrains both had flow during the first quarter. The flow and mass average <br />conductivity of the underdrains for the last ten years is summarized in the table below. <br />Flow is presented in acre-feet. Conductivity is measured in umhos/cm. <br />The underdrains were cut off and buried with rocks during the fourth quarter 2008