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The surface flows in Ward Creek are a calcium-bicarbonate type water of <br />generally good quality. It has a total dissolved solids concentration of 32 <br />mg/1 at the upper sample site, and 396 mg/1 at the lower site. This increase <br />in totai dissolved solids may be partially the result of the flood irrigated <br />agricultural activities occurring in between the two sites. Additional water <br />quality analyses for Ward Creek and some of the ditches fn or adjacent to the <br />permit area are provided in Figures 2.04.7(2)(b)-1 through <6) of the permit <br />application. <br />As shown on Map 8 of Volume 8, numerous irrigation ditches are found in the <br />Ward Creek and Williams Creek valleys. Eleven major ditches were identified <br />in the Ward Creek valley, and six major ditches were identified in the <br />Williams Creek valley. In addition, numerous lateral ditches exist to <br />distribute water from the main ditches. The principle source of water for <br />these irrigation systems is Granby Ditch (Granby Ditch and Reservoir Company) <br />which transports irrigation water from reservoirs on Grand Mesa. This water <br />is discharged into Ward and Williams Creeks for subsequent diversion by the <br />various irrigation ditches. Flow data for the major ditches during 1979, <br />1980, and 1981 is included in Table 11 of Volume 8. Additional flow and <br />quality data for ditches and Williams Creek is contained within the document <br />entitled "Grand Mesa Coal Company Water Monitoring" submitted in May, 1983. <br />The applicant has identified four springs in or adjacent to the Red Canyon <br />Mine (shown on Map 2 of the addendum, Kimball, et. al., 1982). The source of <br />two of the springs is the Lower Williams Fork Formation and the source of the <br />other two is the alluvial-glacial fill. Quality and quantity data is <br />contained in "Grand Mesa Coal Company Water Monitoring" submitted May, 1983. <br />Probable Hydrologic Consequences of Mining <br />The applicant has provided a discussion of the probable hydrologic <br />consequences of the proposed mining operations on surface and ground water <br />systems. This assessment, based upon mining in the D and E coal seams at a 50 <br />to 55 percent recovery rate, is found in Settion IV of the addendum (Kimball, <br />et. al., 1982). <br />The proposed operation would undermine the Williams Creek and Ward Creek <br />stream/alluvial aquifer system. The applicant has limited coal extraction <br />beneath the valleys and no significant subsidence effects are expected. No <br />major fractures have been identified in the permit area. The applicant has <br />identified inflows to the mine (Volume 8, Map 6), but has not found <br />significant inflows from the roof which would suggest communication with <br />overlying aquifers. In addition, the applicant's ground water investigations <br />show no vertical communication between aquifers. Based on all of this <br />information, no significant depletion of flow is expected to occur vertically <br />through the strata overlying the underground workings. <br />-30- <br />