2010-12-17_REVISION - C1981019 (153)

Home Browse Search

Surface water 27 Surface water below the confluence of the east and west forks of Jubb Creek (CJC) is characterized as a magnesium - sulfate water (Figure 4.3). Compared to other stream waters, this water has a higher percentage of sodium. The pH ranged from 8.29 to 8.61, except when the creek was frozen (pH = 7.19). The TDS ranged from 1,590 to 1,800 mg /I. Concentrations of Total Suspended Solids (TSS), were below the detection limit of 5 mg /I in all samples. Samples collected by KEC in 1996 and 1997 are very similar to the samples collected during the pre - feasibility study (Appendix 4.C). One interesting time trend observed in the data is the abrupt change in concentrations during the spring runoff, which occurred in May and June in 1997. During this event, concentrations of all ions decreased, although the overall inorganic signature of the water remained the same. Historic data from the upstream East and West Jubb Creek sampling locations (EFJC and WFJC) indicate that the water is very similar to samples from CJC, except for a lower sodium percentage. Between 1997 and the 2004/2005 sampling event, a dam was constructed between sampling locations WFJC and CJC. The water quality in Collom Gulch varied with location and time. At the upstream sampling location (UCG) the water is a calcium /magnesium- bicarbonate (Figure 4.3). Only two samples were evaluated, as the stream was dry during the first two sampling rounds. The inorganic chemistry of the water was very similar in both samples, with a slightly alkaline pH of 8.37 to 8.51. TDS ranged from of 380 to 490 mg /I, with the lower value originating from the sample collected during the March spring runoff. TSS ranged from 200 to 380 mg /l. The chemistry at the downstream sampling location (LCG) is characterized as a calcium /magnesium- bicarbonate (Figure 4.3). The pHs of the samples ranged from 8.21 to 8.35, with the exception of the December 2004 sample, which had a pH of 7.19 and was collected from below 4 inches of ice. TDS ranged from 820 to 870 mg /I, with the lower values occurring during the spring runoff in March. TSS ranged from 21 mg /I during the winter to a high of 452 mg /I during the runoff. The water quality in Straight Gulch at both locations (USG and LSG) is a magnesium — sulfate /bicarbonate (Figure 4.3). The inorganic chemistry of the water was very similar for all samples, with a slightly alkaline pH of 8.06 to 8.54. TDS ranged from 830 to 1,430 mg /I. TSS ranged from 18 mg /I to 816 mg /I, with the highest concentrations occurring during the runoff. 4.5 Springs and seep Springs and seeps were inventoried and sampled in December 2004. As discussed above, the focus was springs and seeps within and downgradient of the proposed mine. Areas in the Collom study area were evaluated where enhanced vegetation and grasses indicated the potential for seeps. Ten spring locations were identified and inventoried. Most of the springs and seeps located by WMC staff had been previously identified during the JBR study conducted for the Collom study area (JBR, 1998). • 2572 -R2 Colowyo Coal Company Water Management Consultants