Laserfiche WebLink
Permit C-81-071 1995 Annual Hydrology Report <br />Water Quality <br />The summary of the 1995 spoil spring field data is presented on Table 47. The summary of the <br />water quality data for Station 114 is presented on Tables 51. Additional spoil spring data is <br />presented on Tables 48 and 49 for Mine I and on Table 50 for Mine 2. Plots of the historic water <br />quality data for Station 114 are presented on Figures 43 and 44. <br />The data for the Mine 1 spoil springs flow show a maximum field conductivity value of 4290 <br />umhos/cm with a flow weighted average value of approximately 2960 umhos/cm during the <br />1995 water year. The data for the Mine 2 spoil springs flow show a maximum field conductivity <br />value of 9540 umhos/cm with a flow weighted average value of approximately 3000 umhos/cm <br />during the 1995 water year. During the winter when Foidel Creek flows are dominated by spoil <br />spring discharges, the creek's conductivity level approaches that of the spoil springs. The <br />conductivity of the spoil springs shows temporal fluctuations that most likely reflect spoil <br />recharge events of low TDS snowmelt. The lowest TDS concentrations in the spoil springs <br />occur during the Spring snowmelt period. <br />Figure 50 indicates that the water quality in Foidel Creek is dominated by the water quality of <br />the discharge from Pond A. Pond A receives the discharge of the largest spoil springs. The <br />spoil spring 114 discharge is characterized by high dissolved solids, calcium, magnesium, <br />sulfate and SAR compared with bedrock groundwater, other spoil springs and unaffected <br />surface waters. Station 114 also shows comparatively high manganese and high nitrate levels. <br />Most of the Mine 1 spoil springs have elevated manganese levels. <br />• Due to the small size of the flows (approximately 0.28 cfs during spring runoff) the spoil spring <br />discharges from Mine 2 have no impact on Fish Creek. <br />EFFLUENT MONITORING <br />A number of sedimentation control structures at Mine 1 and 2 are monitored. Of these only <br />Stations 39 (Pond A), 84 (Pond D) and at Mine 1 had significant flows during the 1995 irrigation <br />season. Stations 57 (Pond H), 41, 87 (Pond F), (Pond K), and 91 (Pond M) showed minor or <br />no flows only during the spring runoff. None of the stations at Mine 2 had significant flows in <br />1995. Most of the Mine 1 ponds are in the Foidel Creek drainage, only Pond H (Site 57) is in <br />the Middle Creek drainage. Pond M on Mine 2 is in the Fish Creek drainage. Pond D (Site 84) <br />receives inflow from the waste rock disposal area as well as well as runoff from the surface <br />mine. Pond K (Site 41) drains to Foidel Creek and had no discharge in 1995. <br />Flogs <br />The flow rate data for the effluent stations are summarized on Table 52. The historic discharge <br />data for the ponds with significant 1995 water discharges at Mine 1 are presented in Figures 42 <br />and 45 through 45. Discharges from these ponds are affected by seasonal variation in surface <br />runoff and spoil spring flows. All of the plots show the typical seasonal variation with high flows <br />during spring runoff. Historically, discharges from the ponds ceased in the summer and did not <br />begin again until the next spring. Three ponds, A (Site 39), D (Site 84) and F (Site 87), began <br />discharging year round in late 1984. This is due to the spoil springs located in the drainages of <br />EPSTE%T.DOC 03/14/96 Page 7 <br />