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Underdrains were installed in the base of the restabilized mine bench starting <br />in November 1984 and finishing in June 1985. Three drains are exposed at the <br />toe of the bench. These drains have been individually sampled to date but <br />will be sampled collectively when connected by a common ditch in the summer <br />of 1986. The average conductivity for the north drain was 1885 umhos/cm with <br />a pH of 7.8. The middle drain only Elowed once with a conductivity of 1974 <br />and a pH of 7.0. The south drain had an average conductivity of 3328 and <br />a pH of 8.1. <br />MINE WATER <br />Inflows into the mine continued to be pumped to the surface until November <br />19, 1985 when the decision was made to discontinue pumping. Between the first <br />of the year and October 9, 27.7 million gallons were pumped to the 111 Pond <br />with an average conductivity of 12.67 and a pH of 8.1. Between October 9 and <br />November 19, 4.8 million gallons with an average conductivity of 1200 and a <br />pH of 7.4 were pumped to Hubbard Creek through discharge point 004. The following <br />is a listing of the average monthly discharges (gpm): <br />January 38.3 May 72.0 September 72.5 <br />February 53.8 June 80.7 October 80.3 <br />March 53.9 July 86.8 November 82.6 <br />April 59.7 August 83.7 December None <br />Pumped <br />Information for 1985 mine inflows map was gathered the end of June when inflows <br />were near their peak. Inflow at area 4 continued to be the primary source <br />of water. In the area of 2 and 3 all four entires showed minor inflows <br />in the form of water dripping from the roof. This area of inflows amounted <br />to approximately 2 gpm. This water in the roof caused a roof fall at crosscut <br />16 in the return (the west entry). Area 10 was damp in years past but had <br />shown no measureable inflow. Inflows this year of 4.5 gpm in area 10 cam <br />primarily from the west rib. Area 11 didn't have a measureable flow but <br />did have wet ribs and roof. A roof fall was caused in this area by water in <br />the roof at crosscut three in the return. A line at crosscut 23 shows the approximate <br />water level in the mine at the end of 1985. <br />CONSUMPTIVE USE OF WATER <br />The source of consumptive water for 1985 was mine discharge. Using the rational <br />for the permit application the estimated consumptive water usage was as tollows: <br />