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Dan Hernandez Page 8 <br />June 3, 2013 <br />and Southfield monitor wells, two additional cross - sections prepared by DRMS utilizing ArcGIS <br />are included as described below. <br />The potentiometric head measured in 1986 is shown on cross - section A -A'. From this <br />illustration, it is evident that the rise of water in the well casing is a function of ground surface <br />elevation, depth of overburden, and total depth of the well. Since water in the coal zone(s) is <br />isolated from other stratigraphic units by interbedded impermeable mudstones and siltstones both <br />above and below the coal zone(s) there is no interconnection or comingling of saturated zones <br />and the vertical movement of groundwater is greatly restricted. The water level information <br />presented in the 1987 report represent potentiometric head given the confined condition of the <br />coal zones as opposed to static water level measurements. In a confined saturated zone /aquifer <br />such as is the case with the Jack O'Lantem and Red Arrow coal seams the water rises as much as <br />several hundred feet above the perforated interval of the well. These potentiometric surfaces do <br />not exist between the wells in the natural in -situ conditions. In general, groundwater movement �e <br />in the coal zone would be down -dip in the down gradient direction of the steeply dipping coal i[er <br />beds. In the immediate vicinity of the recent mine workings; however, local groundwater <br />gradients will be toward the void space of the mine, until the workings are full. If the wells had <br />been completed in an unconfined, homogeneous and isotropic aquifer then the conclusion about <br />groundwater flow direction in the 1987 report would have been an accurate prediction. The 1987 <br />Southfield Mine Water Rights Engineering Report states that groundwater movement in the <br />Vermejo Formation is to the northeast and is tributary to Newlin Creek. The report further states <br />that "Prior to mining operations, ground water in the Red Arrow and Dirty Jack O'Lantern coals <br />discharged to the Newlin and Hardscrabble Creek basins as base flow." As part of our study of <br />the groundwater flow regime, we prepared numerous cross - sections utilizing ArcGIS with all <br />available monitoring data. These cross - sections show that in the vicinity of Newlin Creek within <br />the permit boundary the coal seams mined are greater than 100 feet below Newlin Creek and <br />groundwater discharge from the coal seams and /or mine workings flows to the northwest below <br />and away from Newlin Creek. Please see the schematic cross - section A -A', the Generalized <br />Cross Section Depicting Well Completions, and two computer generated cross - sections titled <br />View to the North, looking down on the permit area at about 45 degrees and View to the <br />Northeast, looking up at the permit area at about 45 degrees (land surface shown) all <br />incorporated in Appendix C for reference and which illustrate our interpretation of the ground <br />water flow direction and movement. <br />Groundwater flow direction is actually to the northwest as opposed to the northeast as originally <br />presumed and it flows along the dip of bedding planes and the coal seams at approximately 5 <br />degrees. This is verified by the MSHA Permanent Closure Map prepared for the Southfield <br />Mine site. The strike and dip of coal beds is shown on this map and it is to the northwest at 5 °. <br />This is also consistent with Map 5 Regional Hydrogeologic Map contained in the PAP. As <br />shown on this map the groundwater flow direction within the Vermejo to the west - northwest. <br />Adjudicated Wells within the Permit and Adjacent Areas <br />Groundwater resources in the permit and adjacent areas are limited in extent due to lenticular <br />lithologies of the potential water - bearing units and because of previous underground coal mine <br />dewatering. Three adjudicated wells were identified within the permit and hydrologically <br />