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-15- The second water-bearing zones, the Vermejo Formation aquifers, are, in their natural state, perched and discontinuous. 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 emergency water from a well completed in the abandoned Caldirola No. 2 Mine. Water quality varies within wells completed in abandoned mine workings. Water quality from the Caldirola No. 2 Mine well is good, rarely exceeding the E.P.A.'s water quality standards for human consumption for 7DS (tota] dissolved solids). However, analysis of water from one of the adjudicated wells in the southern part of the Canon City Coal Field also completed in an abandoned mine showed poor water quality. Here, water exceeded the E.P.A.'s drinking water quality standards for conductivity, total dissolved solids, ammonia, sodium sulfate, iron and manganese as presented in section 2.04.7 of Dorchester Coal Company's second adequacy response. 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. U.E.S. monitoring requirements for iron, manganese and total dissolved solids by over 1000 percent. As is discussed in the cumulative hydrologic impact study of this document, the Vermejo Formation aquifers may be affected. The third water-bearing zone, the localized, shallow alluvial aquifers along drainages, have been extensively disturbed by previous surface coal mining operations. Because coal outcrops were visible in eroded areas (i.e. drainagesj, this was where portals were located. Underground development waste was 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. Therefore, little pre-mining baseline information is available on the potential alluvial aquifers within the penmit and adjacent areas. The potential for impacts to the alluvial aquifers as a result of mining is considered negligible. Ground water flow into the three previously mentioned aquifers is derived primarily from the recharge areas near the Wet Mountain Fault. Insofar as 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. Studies indicate that the discharge points for the Trinidad Sandstone and the Vennejo 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 six miles north of the proposed Twin Pines No. 2 Mine. Information available from the U.S. Environmental Protection Agency shows that 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 bsu cl~l basin, as located on the attached Index Map, Figure 1. It \~