Laserfiche WebLink
JD-6 Mine Report <br />Geoscience Services <br />For the simulations, a conservative approach was adopted that assumed aworst-case <br />scenario. Because there is a limited amount of technical data available for the hydraulic <br />and transport parameters of the geologic strata under the site, these parameters were <br />estimated using the best available geotechnical data available from the literature. Since <br />there is commonly a range of values associated with these hydraulic and geochemical <br />parameters, values that result in the highest transport rates were selected. <br />2.0 Site Description <br /> <br /> The JD-6 mine is located on the southwestern flank of Paradox Valley-a <br /> breached anticline (Figure 1). The regional dip in the area is to the southwest away from <br /> the center of the valley. Since the geologic structure will control the movement of <br /> <br /> groundwater, the regional flow direction is also in a southwest direction--especially for <br />. the Entrada Sandstone aquifer. This area is also characterized by a series of fault <br /> controlled rotational slumps where large blocks of bedrock have slid downward (Figure <br /> 2). The dip of these blocks is also in a southwestern direction but can exhibit a greater <br /> dip angle due to the rotational movement of the bedrock. <br /> <br /> According to Cater (1955), the waste dump for the JD-6 mine is located on the Salt Wash <br />• Member of the Morrison Formation. Infiltrating water would move through the waste <br />~ dump material into the underlying Salt Wash sandstones and mudstones, through the <br /> Summerville Formation, and eventually enter the Entrada Sandstone. Since the geologic <br /> structure controls the movement of groundwater, once water enters the Entrada it would <br />~ flow to the southwest-away from Paradox Valley. It is unlikely that groundwater flow <br /> <br />* in the Entrada would extend for any significant distance since the formation is terminated <br />• along the rotational fault plan. <br /> <br /> There is the possibility of subsurface water movement along the bedrock and the nearby <br /> landslide and alluvial deposits. Infiltrating water could move along this <br />~ consolidated/unconsolidated rock interface toward the center of the valley, Considering <br /> the rate of groundwater flow, typical on the order of tens of feet per year, the bulk of this <br /> <br /> 2 <br /> <br /> <br />