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Doc Date:12/11/2001 ~ III IIIIIIIIIIIII III sss I somewhat reduced flows. Area I, Sylvester Gulch Return, which averaged about 18gpm during 1985 averaged 2gpm during 1986. Inflows into Area I were responsive to spring runoff as peak inflows were estimated at 20 to 25 gpm during the June survey. Dewatering of the Sylvester Gulch Return (Area I) was only necessary for 3 to 4 months coinciding with spring runoff and about 2 months lag time. Water discharged from the mine was of low quantity and quality was good (See Tables 1.4-1 through 1.4-3). Area II, old Sylvester Gulch Returns 1 averaged about 1.8 gpm in 1985. In 1986 flow was less and was estimated to be about 0.5 gpm for the year (average). Area III, outcrop areas near main portals averaged about 4.1 gFm in 1985. As with other areas, 1986 flow was significantly less and was estimated at be 0.25 gpm for the yearly average. Only a small amount of mine water was discharged from the portals into hID-1 this water left the mine by gravity drainage from the portals and by gravity drainage through the piping system. Flows from the portals were small and were not measured. Flows from the piping system sere also small as no flow large enough to turn the fla~m~eters occurred. New areas mined in 1986 encountered very little water. Roof drippers and floor seeps were encountered in the 1st West Submain in an area under Lone Pine Gulch -~ where overburden was low and the roof of the mine highly fractured. Flow was so small as to be not measurable. Similar conditions to 1st West were encountered in the 1st East Submain as floor and rib seeps were visible. Flora here was too small t.O measure. No water was encountered in the 1st South Panel either on advance or during retreat mining. I Auring the mine inflow survey samples of mine inflavs were taken. Samples were tested for pH, electrical conductivity, total suspended solids, total dissolved solids, and total iron (Fe). Results of these samples is provided in Table 1.4- 2. The quality of all water sampled is good and poses no problem for direct 1 discharge or discharge bo a sediment pond as it meets or in most cases is much higher quality then required by NPDFS permit effluent limitations. 7 Area I discharges primarily out of the fan housing directly into Sylvester l Creek. Area II discharges either our Sylvester Gulch or out Portals 1 and 2. Area III discharges out the west fan (portals). Water pumped into the mine is calculated by subtracting potable water processed from water pumped fran the North Fork. This is an estimate since there is no adjustment for evaporation fray Ft~l or for change in storage in FW-1 from one year to the next (FW-1 water level usually remains fairly constant at between 60 and 90 percent capacity). Table 1.4-3 shows the mine water balance and associated water useage and discharge figures. Water unaccounted for is lost I through seepage and evaporation into the ventilating air. Both of these losses can be substantial depending on ~nditions. I 2.0 Avdrologic Data Interpretation and Impact Assessment for Permit Area and Adjacent Areas This section crontains an analysis of hydrologic data gathered during Water Year I 1986; and assessment of i~acts on mining on the quality and quantity of water in surface streams, springs, groundwater aquifers, mine inflows, and discharges during Water Year 1986, and an estimated of potential impacts of mining on these I waters during Water Year 1987. (7)