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• and fall although none of the springs or associated ponds sustained <br />flow throughout the summer and fall. Ponds associated with springs <br />that dried out included SP-12-4 and SP-13-5. Ponds which did not <br />dry out were SP-7-5, SP-12-11, SP-13-6, SP-13-7, SP-19, SP-23, <br />SP-24 and SP-28. <br />Pond and spring SP13-5 was one of the ponds which dried up by July <br />29, 1991. However, on September 4, 1991 the pond was again full. <br />The pond lies outside the projected angle of draw for panel A. <br />However, if mining in panel A and associated subsidence impacted <br />the spring and pond, the impact was very temporary. Overburden <br />cover in the vicinity of the pond is about 625 feet. <br />• Only about half of the springs flowed during water year 1991. The <br />springs that flowed showed typical seasonal variability: the flow <br />rate decreased and the conductivity increased each summer. None <br />of the Stevens Gulch springs sustained flow throughout the summer <br />and fall of 1991. <br />Water quality type of most of the springs is calcium bicarbonate. <br />The total dissolved solids and relative concentration of sodium and <br />sulfate increases in the lower elevation springs. This is <br />apparently the result of the geochemical influence of the colluvium <br />and weathered rock derived from the upper coal member in these <br />lower elevation springs and ponds. Similar differences in chemical <br />composition of water samples from the upper coal member in <br />• comparison with the barren member of the Mesaverde formation have <br />also been observed at the Mt. Gunnison mine located within the <br />6 <br />