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• et Yell YY30. Well YY2 hea water levels ranging from flowing to 7.57 feet below ground surface. The Yedge coal is entirely saturated et ell locations except at Yell YV14, where the coal ie dry, and et Vell YY26 where the coal is 48 percent saturated. Table 7-b shows the saturated thickness and pe reent saturation et each of the Yadge coal wells monitored. The large range in water levels for the Yedge coal seem is a function of boring depths, completion intervals, proximity tc outcrops, and topography. As can be seen from Tables 7-2 and 7-b, several of these wells ere pertly completed in the Vadge overburden or underburden, or only partially completed in the Vadge Coal. A slight amount of overdrill is necessary to ensure that the entire coal unit is open to the well. Wells YY12 and YV24 have infilled to such en extent that they are no longer valid for water quality sampling, nor perhaps for water level monitoring. Seasonal water level changes have been measured in the Wedge coal seem (Appendix 7-2). There is no dist(nct trend concerning seasonal mean water Levels. The shallowest mean water levels occur principally in the spring (six wells), but also occur in the summer (Well YY18 ), fall (Yells YY21, 26, and 30), and winter (Yells YV24 and YY28). Pater level • date from Yell TV2 is not included in this discussion as no meaningful trends can be ascertained from this well; however, it is clear that the October 15, 1980 level of 23.52 feet for this well is probably en error, and quite possibly represents a level measurement collected at Yell YOY1 instead. It should also be noted that several water levels given for Yell YY7 (those less then 118 feet) are considered erroneous; the June 2, 1993 level of 121.41 feet given for Yell YY11 should actually be 129.41 feet; and water levels greeter than 26.0 feet ere not considered representative for Well YV14 as this is merely water residing in the bottom end cep of that well. The dominant form of recharge to the Yadge coal seam appears to be snowmelt. Summer or fell reinf all appears to provide significant recharge to some portions of the Yadge coal seam, although there may be a delayed response to spring recharge at some Yells. The deepest mean water levels appear to occur in the summer (at two wells), fall (at four wells), and winter (at six Yells). Seasonal water level fluctuation also shows no distinct trend. Five wells showed the greatest fluctuation in the spring, five in the fall, and two in the winter. Eight wells showed the least amount of water level fluctuation in the winter, two in the fall, end two in the summer. Minimal seasonal • fluctuations range from 0.34 feet et VeLI YY26 to 14.59 feet et Yell YY18. The greatest seasonal fluctuations range from 1.41 feet at 4ell TV14 (which is typically dry) to 23.81 feet et Yell YV18. Premining water level fluctuations in the Yadge coal are appreciable, 17