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The Dakota/Burro Canyon Formations in the JD -9 mine area consists of erosional <br />remnants of resistant sandstones and pebble conglomerates that form highlands. Large <br />areas of exposed sandstone along the top of the highland areas provide access for <br />precipitation to collect in depressions and infiltrate into the bedrock. Compared to the <br />available recharge areas along canyon walls, the Burro Canyon highlands provide a <br />significant increase in the area available for recharge from the limited amount of <br />precipitation. Across the Colorado Plateau, springs can occur at the contact of the Burro <br />Canyon and shales of the underlying Brushy Basin Member of the Morrison Formation <br />where downward movement of groundwater in the sandstones and conglomerates is <br />restricted by the low permeable shales. <br />Mining activities in the area would have no impact on the overlying groundwater in the <br />Dakota/Burro Canyon. However, water from Dakota/Burro Canyon enters the mine at <br />ventholes that penetrate the formations on Monogram Mesa. There are no mapped <br />springs in the Burro Canyon highlands immediately above the JD -9 mine site but there <br />are indication of seeps as indicated by the vegetation. Groundwater in Dakota/Burro <br />Canyon Formations would be restricted from recharging the mineralized zone in the Salt <br />Wash Member by the low permeable shales in the Brushy Basin Member of the Morrison <br />Formation. <br />There is a small spring near the mine portal that discharges water from a perched water <br />zones from a sandstone lens in the Brushy Basin. <br />Groundwater occurs in the upper sandstone unit of the Salt Wash Member of the <br />Morrison Formation. In the mine, water is observed in the sandstone rock underlying the <br />ore zone and appears in discontinuous lenses within the mining area. The occurrence of <br />groundwater in the upper sandstone unit of the Salt Wash Member of Morrison <br />Formation is unique to the Monogram Mesa area of the Colorado Plateau. Resistant Salt <br />Wash sandstone units form highlands or benches in the area. Gregory Creek/Steer <br />Canyon located to the north of JD -9 or the Fawn Springs bench, south of the mine area, <br />are locations where the Salt Wash member is a resistant geologic unit that forms <br />relatively horizontal topography. Similar to the Burro Canyon Formation, the large areas <br />of exposure allow precipitation to recharge the sandstone. <br />Permeability values for the Salt Wash indicate that the formation is not an important <br />source of groundwater. Fawn Spring is located in the Salt Wash Formation but the spring <br />is little more than a seep only capable of supporting limited amounts of local vegetation. <br />It is highly unlikely that a well drilled in the Salt Wash would be capable of supplying <br />adequate amounts of water for domestic consumption. Poor water quality would further <br />limit the viability of this potential groundwater resource. <br />There is no data available to definitively indicate if the Entrada is a viable aquifer in the <br />area. Colorado State Engineer well records indicate that there are limited amounts of <br />water available in the formation. There is evidence that the underlying Navajo formation <br />contains groundwater. Several studies in the area indicate that the Navajo contains <br />substantial quantities of water in the Colorado Plateau area. There is a spring located in <br />O'Connor Design Group Inc. U - 13 <br />