Laserfiche WebLink
r~ <br />u <br />Piopattd Hydralopmt Mwtirainr Hw fa ~M1e Nd Narircn Mou 3 <br />non-irrigation season and 03 cfs to 2.7 cfs during the irrigation season. The majority of flow <br />observed at these two stations is a result of irrigation return during that season. Flows at <br />stations SW-N104 and SW-N105 located on the West Enteral Ditch varied from 0.0 during <br />the non-irrigation season to 27.9 during August 1988. Hydrographs for the period of record <br />for each of these four stations are contained with the data in Appendix A. <br />Surface water quality data collected from stations SW-N101, SW-N102, SW-N104, and SW- <br />N105 are wntained in Appendix B for the period of record of July 1986 through February <br />1990. Minimum and maximum values for conductivity, Ph, temperature, and total dissolved <br />solids are contained in Table 2. This information is presented for the irrigation season <br />(Apn7 through September) and the aon-irrigation season (October through Mazch). <br />Trilineaz and stiff diagrams of water quafiry data are contained in Appendix C. As indicated <br />from these data summazies, there is a significant difference in water quality from the <br />irrigation season to the non-irrigation season Water quality during rile irrigation season at <br />stations SW-N102, SW-N104, and SW-N105 is a mhted calcium-sulfate bicarbonate type <br />water with lower total dissolved solids. On Calamity Draw at station SW-N101, the water <br />quality shifts slightly to a mixed magnesium/calcium-sulfate type water. Generally, water <br />quality in Calamity Draw is of a better quality during the irrigation season due to irrigation <br />return. This can be noted by the higher flows and lower total dissolved solids. There were <br />• no surface water violations of water quality standazds (Table 3) during the period of record. <br />Groundwater Monitoring <br />Topography is the principal element governing shallow aquifers (<400 feet) in the Canyon <br />Land Section of the Colorado Plateau Physiographic Provide. Groundwater flow is <br />anticipated to move in the direction of surface relieL <br />There are 24 groundwater wells located in the vicinity of the New Horizon Mine 2 site. <br />Table 4 provides the completion information for these wells. Of these, only 12 wells are <br />deemed appropriate to analyze for the new mine plan (see Map 2.04.7-1). Appendix D <br />contains the groundwater level data with a hydrograph of each of the 12 wells for the period <br />of reeord from Iuty 1986 through February 1990. Water in the Calamity Draw alluvium was <br />monitored at GW-N22. Water levels varied seasonally wi[h a continuous rise in levels during <br />the irrigation season The peak was observed during the fall (September/OMober). Water <br />levek in the overburden at wells GW-N15, GWN18P1, and GWN21 also varied with the <br />irrigation, reaching a peak in the hydrograph doting the period of May through September- <br />Variation in water level was as much as 25 feet between the irrigation and non-irrigation <br />seasons. The Dakota Coal seams was monitored at wells GW-Ni4, GW-N17P1, GW-N20, <br />and GW-N30. Water ]Duels in these wells follow the same seasonal variation with irrigation, <br />however, are not as variable as Lhe overburden. Water levels vatted 5 to 15 feet beiweeq <br />the irrigation and aon-irrigation seasons, wish well GW-N30 being artesian during the peak <br />• <br />Attachment 2.04.7-5-26 <br />