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• significant trends or adverse impacts related to mining at Mines 5 and 6. <br />COAL <br />FLOWS <br />Plots of the measured discharges for the iwo #5 Mine discharge points are presented <br />in Figures 16 and 17. The flows are measured at the discharges by totalizing flow <br />meters on the dewatering sump pumps. The mean flow rate recorded for the No. 5 <br />Mine discharge point (approximately 830 gpm) was noted to exceed previous years <br />measurements. This may have been a reflection of the unusually wet spring <br />experienced in the area. The water produced in the No. 6 Mine is pumped <br />underground to the No. 5 Mine sump and where it then is pumped out of the No. 5 <br />• Mine Discharge point. The combined mean discharge, including the 7 North Angle <br />discharge point, of approximately 1025 gpm for the #5 Mine in 1995 was the highest <br />level recorded to date although 1981 and 1982 figures approached this level. The <br />short term fluctuations in weekly discharge rates (Figure 17) are a function of pump <br />capacity, periods of pump shutdown or failure, and the fact that the pumps operate <br />periodically based upon water levels in the underground sumps. <br />WATER QUALITY <br />Summaries of the water quality data for the mine discharge are presented in Tables <br />17 through 20. The #5 Mine sump discharge is NPDES discharge point #003. The 7 <br />• <br />C-81-044 1996 AHR. I \EMPIREWHR\96AHR\EMPAHR98.DOC Page 7 <br />