Laserfiche WebLink
The maximum discharge of the mines coincides with the <br /> maximum spring melt runoff period. This mitigates the higher TDS <br /> levels by immediate dilution. The mine discharges (1 & 2) <br /> enter the Dutch Creek drainages some 4 miles above their junction <br /> with Coal Creek thus again diluting and mixing. Stream gaging <br /> station No. 5 Dutch Creek above Coal Creek has the following <br /> averages (1976-1985) . <br /> Maximum Mean Minimum <br /> TDS 1155. 393. 2.09 <br /> TSS 12398.* 689. 0 <br /> Iron 59.4 1. 3 0 <br /> PH 8.9 8 .03 6 . 8 <br /> Conductivity 1390. 571. 160. <br /> *Summer thunderstorm with stream bank failure. <br /> Compare this with Sutey Creek an unaffected drainage . to the <br /> north of the main coal refuse pile. <br /> Maximum Mean Minimum <br /> TDS 632. 528 . 320 . <br /> TSS 2880. . 721. 6 . <br /> Iron 45. 6 5.5 . 02 <br /> PH 8.4 7.8 7.1 <br /> Conductivity 900. 721. 410. <br /> It is apparent by this comparison that by normal dilution <br /> the mine discharge and other disturbed areas are mitigated. <br /> All disturbed areas of the mine (290 ac. , 0.45 sq. mi. ) have runoff <br /> water routed through sediment ponds which release water with suspended <br /> solids levels well below that of the natural undisturbed streams <br /> during high flow conditions. <br /> 53 <br />