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• 10 • <br />Geologic structure, to a great extent, controls the prevailing direction of ground- <br />water flow in the area to be affected over the life of the proposed mine. Structura.I <br />highs (Tow Creek Anticline) act as groundwater divides and recharge areas; whereas <br />structural lows (synclines) and alluvium act as areas for groundwater discharge. <br />Faults in the vicinity of the mine act as barrier boundaries. <br />PUMP TEST ANALYSIS <br />Pump tests performed on the overburden, Wadge seam, and the [volf Creek seam indicate <br />that the water availability from these units is extremely low. Transmissivity For <br />the Williams Fork Formation ranges from .01 ft2/day (0.07 gpd/ft) for the Wolf Creek <br />to 377 gallons per day per foot for the Wadge seam. Of primary concern to Seneca <br />Coals Ltd. is the Wadge coal seam and Wolf Creek seam. To obtain a transmissivity <br />for the Wadge coal seam, a pump test was performed at the Seneca II mine on we21 <br />numbered GW-517. Wolf Creek pump test information is extrapolated from the nearby <br />Seneca II-W area. At the Seneca II mine, Wadge overburden pump tests are planned <br />for the summer 1981 field season in the southern part of the permit area. Currently, <br />pump test data are not available For the alluvium and spoil materials. Aquifer' <br />pump tests are planned for the alluvium and spoil materials in 1981 and will be <br />supplied to the Division after these tests are performed and analyzed. <br />WITHIN 30 DAYS OF PERMIT ISSUANCE, THE OPERATOR MUST SUBMIT THE RESULTS <br />AND ANALYSIS OF THE PUMP TESTS FOR THE ALLUVIAL AND SPOIL AQUIFERS. THIS <br />SUBMISSION MUST BE INCLUDED IN THE PERMIT APPLICATION DOCUMENT. <br />Analyses of the Wadge coal seam indicate the Wadge coal seam is semi-confined <br />(storage coefficient 2.8 x 10-z). Having a transmissivity of 9.68 m2/day (377.24 <br />gpd/ft.), the Wadge coal seam is considered not to be an important aquifer in terms <br />of water quantity. In addition to low water availability, it has generally, poor <br />quality; therefore, it is not considered an important regional aquifer. <br />the Wolf Creek coal seam will also be disturbed by mining. This seam has a Lowest <br />transmissivity of those strata tested in the area. 2'he Wolf Creek is not considered <br />to be an aquifer based on its poor water yielding ability and chemical quality. <br />GROUND WATER QUALITY <br />Groundwater quality within the general area appears to vary considerably from aquifer' <br />to aquifer. The quality of groundwater in the region is considered to be poor for <br />domestic use and may contain excess concentrations of sulfate, fluoride, iron, <br />manganese, selenium, total dissolved solids, and hardness. Excess concentrations <br />of arsenic and nitrate may occur in alluvial aquifers in addition to the above <br />constituents. <br />Water quality information from wells monitoring undisturbed areas adjacent to the <br />Seneca II permit area have been compiled by Seneca Coals Ltd. and the U.S. Geo- <br />logical Survey to further document groundwater quality in the Williams Fork For- <br />mation. <br />Studies by Seneca Coals Ltd. show that groundwater in adjacent areas [/est of the <br />Seneca II permit area is slightly saline, with calcium, magnesium, sulfate, and <br />