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-~- The Cretaceous formations Kaye been folded, sometimes overturned, against the Wet Mountain fault to the 41est. The resulting Chandler Syncline is asymmetrical with the axis trending North-South. The eastern mineable flank dips 6°- lO° south-west towards the synclinal axis. 7'he coal outcrops are obscured by 30 to 50 feet of piedmont alluvial/co.lluvial material which has washed dawn from the mountains to the west. The permit area is dissected by two ephemeral. drainages known as Newlin Creek and Magpie Creek as shown on Maps 8 and 9 of the application and Map 4 of this document. These drainages Eloeu in response to snowmelt and summer thunderstorm events. Four stream monitoring stations were installed as part of the SOAP pro- gram. No significant flow measurements have been recorded since the initiation of the program in April. The major drainage patterns flow from Sothwest ro Northeast toward the Arkansas River. The west half of the permit area and the foothills above is drained by Newlin Creek with a drainage area of 12.2~square miles. Most of the flow of Newlin Creek is diverted upstream for the city uf. Flor- ence. If this municipal diversion would fail, Newlin Creek would flow through the permit area. The Newlin Creek stream channel has been reconstructed across an area called the Prospecting Pit as described in Attachment I and Erhibit B. Magpie Creek, drainage area of 2.4 miles, has been diverted by Dorchester Coal Company around its facility area. (See hlap No. 4 of. this document). Dorchester's diversion forms the boundary in part between its operation and the G.E.C. Mine. The diversion then flows through G.E.C•'s permit area into an adjacent unnamed drainage. The unnamed drainage converges with the original Magpie (:reek drain- age approximately one mile downstream of the permit boundary. The diversion is discussed in the permit application~on pages 2.05-h4 through 2.05-70 and on Maps 8, 8A and 9A. Ground water movement and storage is controlled by the structural feature of the Canon City embayment; the southern portion of the embayment is the C;handl.er Syncline as shown on Map .3 of this document. Aquifers in the general area include the Trinidad Sandstone, the Raton Formation, and the Poison Canyon For- mation. Because of the geologic structure, and the resultant erosion, neither the Raton or the Poison Canyon Formations exist within the area to be mined. The Trinidad Sandstone occurs about 300-400 feet below the lowest coal seam to be mined by G.E.C. Many shales and bentonites, ayuicludes, occur between the coals and the Trinidad Sandstone. Many of the strata within the Verejo For- mation are also water hearing, but are lenticular and yield insufficient water to be considered regional aquifers. Isolated sandstones within the formation may serve as aquifers in some instances. Previously mined seams are disc~ntin- uous aquiFers~yielding vory poor quality water. Post mining activities appear to have significantly affected ground water in the Vermejo Formation as shown by water pumped from wells in the town of Rockvale. The original piezometric surface has been artificially lowered by previous mine- dewatering practices. Most of the nearby underground mine workings exist above this piezometric surface as a result of the past mine-dewatering. Available data indicate that the quality of water in the Vermeju Formation is too saline for