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<br /> <br />' During a site visit in December, 1982. water entered Newlin Creek where <br />the stream crossed the Trinidad Sandstone on the northeastern aide of the <br />Chandler syncline. This entry of water into Newlin Creek from the <br />' sandstone confirms the conclusion derived from the observation well data <br />that ground water movement ie to the northeast. Newlin Creek ie mainly a <br />' losing stream in this reach because the stream channel became dry again a <br />short distance downstream. These observations were confirmed by <br />' streamflow measurements completed in August. 1986. Newlin Creek gained <br />water in the area of the Trinidad Sandstone eubcrop and was a losing <br />' stream in the areas of the Vermejo Formation. upstream from the Trinidad. <br />and the Pierre Shale. dowstream of the Trinidad. The entire reach of <br />Newlin Creek from the City of Florence's diversion to the stream's <br />' confluence with Hardscrabble Creek, a distance of nine miles. is dry most <br />of the year. due to the City's diversions. <br />Figures 6 and 7 are schematic diagrams that illustrate hydrologic <br />conditions prior to and during mining. respectively. The principal <br />sources of recharge are direct precipitation on the eubcrop or outcrop and <br />surface runoff from streams originating in the Wet Mountains. During <br />mining. water enters the mine cavity through irregularly distributed <br />fractures in the formation and from adjacent abandoned mine works. and se <br />l a result. the potentiometric surface of the coal being mined is lowered. <br />J The mine cavity intercepts the water before it ie discharged to the land <br />J surface. However. water is pumped from the mine. used for different <br />purposes. partly consumptively used and then a portion is returned to the <br />l stream system. This may result in a gain to the stream system during <br />I mining. A review of the monitor well water levels for the period of <br />record indicates that no overall trend exists that shows declines in the <br />J water levels at the wells have occurred since current mining activity <br />started in 1979. This shows that the extent of lowered water levels ae a <br />I result of mining ie confined to the immediate vicinity of the mining <br />area. <br />- 13 - <br />