REP10054 - Laserfiche WebLink

Home Browse Search

• Blue Ribbon Mine - AFiR Page 2 GROUND WATER The piezometers on the mine bench were monitored quarterly for water level. Graphs aze included with this report which show historical water levels of the piezometers. The water level in P-1 peaked in Mazch which is typical and then during the summer the water level dropped 9.7 feet to 12.2 feet in November. Piezometer P-2 showed a peak water level in March and then by November it dropped 18.8 feet to a level consistent with prior years records for this piezometer. Piezometer P-3 showed a peak water level in March and then by November it dropped 2].1 feet to a level consistent with prior years records for this piezometer. The piezometer at the top of the bench, P-4, showed little variation during the yeaz. The water level in P-5 averaged 14.6 feet deep during the year. At the end of the year the water level in P-5 was 11.0 feet deep. • Monitoring of piezometer P-6 has been discontinued because it was destroyed by the 1993 bench cover material slump. The north underdrain had less flow than last year. The middle underdrain had measurable flow this year. The south underdrain had more flow during 1998 than 1997. The flow and mass average conductivity of the underdrains for the last seven years is summarized below. Flow is presented in acre-feet. Conductivity is measured in umhos/cm. North Underdrain Middle Underdrain South Underdrain Year Flow Cond Flow Cond Flow Cond 1991 0.018 3030 0.000 0 0.020 4910 1992 0.072 2920 0.000 0 0.034 3960 1993 0.659 2620 0.048 1300 0.761 4450 1994 0.010 2430 0.000 0 0.042 5080 1995 0.088 2640 0.000 0 0.137 4710 1996 0.030 2190 0.0002 1310 0.066 5010 1997 0.112 2420 0.000 0 0.259 5270 1998 0.088 1334 0.084 1060 0.329 3226