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upstream of the formational contacts maybe taken up by the formation that it is crossing. Once <br /> less permeable bedrock is encountered, the streams again exhibit an increase in surface flow. <br /> The nature of the fracture lengths and apertures of the fracturing are not well characterized <br /> within the La Plata drainage. However, as the vast majority of the fractures are in-filled with vein <br /> deposits, it is not unreasonable to speculate that there is a thin zone of fractures in the porous <br /> media adjacent to the in-filled veins and that the veins themselves are relatively impermeable. <br /> Therefore, any flow from the porous media that intersects the veins, follows the vein deposits <br /> based on the potentiometric heads. When an underground working intersects a vein, it offers a <br /> line sink(drain) for the intercepted groundwater to discharge into the workings probably from <br /> the enhanced permeability zone in the fractures adjacent to veins and faults. <br /> Observations of occurrence of water and also staining and evidence of water inflow into the <br /> various underground workings in the immediate vicinity of the Idaho and May Day Mines <br /> supports the contention that there is only minor groundwater flow locally in the upper formations <br /> that will contribute to flow in the mine area(s). <br /> The OPERATOR installed four groundwater wells and one seep to characterize groundwater <br /> quality, and to determine potential well yields and to determine groundwater flow direction: <br /> • The Idaho well (Permit#285909) was initially drilled, however no water was <br /> encountered to a depth of 225 feet below ground surface (bgs) in general proximity of <br /> the Idaho Seep (Appendix Q; <br /> • The well in close proximity to May Day No. 2 mine portal was completed at a depth of <br /> 205 feet bgs with a production rate estimated to be 1.5 gpm (Permit#285910). The <br /> static water level eight hours after drilling stabilized at 53.6 feet bgs. <br /> • A well was also completed adjacent to May Day No. 1 mine portal. The well (Permit <br /> #287129)was competed at a depth of 180 feet bgs with an estimated production rate of <br /> 0.1 gpm. The static water level after eight hours of drilling; stabilized at 131.8 feet bgs <br /> • A twenty foot well (Permit#287229) completed in the La Plata River alluvium <br /> production rate was estimated to be 18 gallons per minute (gpm)with a static water <br /> level of 8 feet(bgs).. <br /> With the exception of the alluvial well, the completed monitoring wells are characterized as low <br /> producing (<2 gpm). The Idaho and May Day No. 2 well have surface elevation of <br /> approximately 8,810 feet above mean sea level (amsl) and static water levels estimated to be at <br /> an elevation of 8,640 feet (amsl). The water level elevation in the La Plata River is <br /> approximately 8,650 feet (amsl). The water producing zones in the completed wells is <br /> approximately the same elevation of the La Plata River and suggests the La Plata River may be <br /> recharging the completed Idaho and May Day No. 2 wells. Static water levels will be observed <br /> during future monitoring events to determine if the recharge flux is towards or from the <br /> monitoring wells. <br /> May Day Idaho Mine Complex <br /> M-1981-185 <br /> January 19, 2017 <br /> Page I - 11- <br />