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-16- The second water-bearing zones, the Vermejo Formation aquifers, are, in their natural state, perched and discontinuous. However, due to its proximity to the mine workings this formation may be impacted by the operation. Water bearing zones within this formation are considered to be poor to poor-to-moderate aquifers that generally produce only small quantities of water (generally less than 10 gpm). Because of the low yield characteristics of the formation, it is a common practice to complete domestic wells in abandoned mine workings to increase yield. For example, in the northern portion of the coal field near the proposed Twin Pines No. 2 Mine, the town of Coal Creek derives a portion of its water supply from a well completed in the old Caldirola No. 2 Mine. Water quality from this well is good, rarely exceeding the E.P.A.'s water quality standards for human consumption for TDS (total dissolved solids). However, analysis of water from one of the adjudicated wells in the southern part of the Canon City Coal Field showed poor water quality. The water exceeded the E.P.A.'s drinking water quality standards for conductivity, total dissolved solids, ammonia, sodium sulfate, iron and manganese. Dorchester Coal Company installed a water quality treatment facility when water from an overlying mine, the Canon Liberty, needed to be discharged. The pre-treatment analysis of the Canon Liberty water exceeded the N.P. D.E.S. monitoring requirements for iron, manganese and total dissolved solids by over one thousand percent. The third water-bearing zone, the localized, shallow alluvial aquifers along drainages, have been extensively disturbed by previous surface coal mining activities. Because coal outcrops were visible in eroded areas (i.e. drainages), this was where portals were located. Underground development wastes were also deposited in the drainages. In addition, previous surface mining in the general area has caused widespread disturbances of the drainage patterns. Many drainages have been impounded by deep pits and the resulting spoiled overburden material has diverted flow. Baseline information is available on the potential alluvial aquifers within the permit and adjacent areas but this data reflects past mining in the area. No use is made of this alluvial ground water aquifer in the southern half of the Canon City Coal Field, where three of the active mines are located Newlin Creek, Dorchester No. 1, and GEC Strip. The only alluvial deposit predicted to be impacted by the operation is the alluvium associated with Newlin Creek as discussed in the AVF section of this document. Ground water flow into the three previously mentioned aquifers is derived from the recharge areas near the Wet Mountain Fault. Ins ofaras the deep ground water flow in the Trinidad Sandstone and undisturbed flow in the Vermejo Formation is structurally controlled by the Chandler Syncline, the water flows downdip towards the axis of the syncline then along the axis north toward the Arkansas River. Studies indicate that the discharge points for the Trinidad Sandstone and the Vermejo aquifers are into the terrace deposits adjacent to the Arkansas River, from where they subcrop beneath the alluvium. Accordingly, the discharge areas for both the Trinidad Sandstone and the Vermejo Formation are approximately nine miles north of the proposed Dorchester No. 1 Mine. This alluvial aquifer along the Arkansas River has been contaminated by radioactive waters derived from a uranium tailings dam on the northeast edge of the subclinal basin. Because of historic unreclaimed surface disturbances in the Canon City Coal Field, infiltration to the alluvial aquifers has probably been degraded.