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r <br />In conclusion, the existing and pending water court decrees and applications, together with the <br />determinations of the professional water engineering consultant, ensure that WFC has adequate <br />water rights for the NHN Mine. <br />Irrigation The NHN Permit area has (since about 1910) and is currently serviced by an <br />extensive man -made irrigation system. The water, primarily used for flood irrigation, is diverted <br />from the San Miguel River approximately 15 miles east of the New Horizon North Mine by the <br />Colorado Cooperative Ditch Company. The irrigation ditches transect drainage basins and <br />commonly run along the basin divides (see Map 2.04.7 -1 for the location of the main irrigation <br />ditch at NHN permit area.). The main irrigation ditches have a network of feeder ditches running <br />from them for irrigating more distant fields. These ditches are a source of ground water <br />recharge, causing ground water mounding in the shallow ground water bedrock system. The <br />effects of seasonal water mounding near the NHN permit area are apparent from monitor well <br />water levels and hydrographs (see Appendix 2.04.7 -1 of Section 2.04.7). Perennial flow occurs <br />in Tuttle Draw and Coal Creek Canyon tributaries as a result of ground water discharge and <br />return flow from the irrigation of the upland area. Site inspections confirm that water used for <br />irrigation is obtained from the San Miguel River and no flood irrigation water is obtained from <br />Tuttle Draw or Meehan Draw. <br />In regard to the agricultural water quality standards, the San Miguel River water delivered by the <br />irrigation ditches is more suitable for irrigation purposes than the waters in the Tuttle Draw or <br />Coal Creek Canyon tributaries. The agricultural suitability (National Academy of Sciences. <br />1972. Water Quality Criteria 1972:National Academy of Engineering, Washington, D.C.. p. <br />335) of surface water in the permit area falls within the category of water that can only be used <br />for salt tolerant plants on permeable soils with careful management practices (TDS from 2,000 to <br />5,000 mg/1). Using the same classification system, water supplied by the 2nd Park Lateral <br />irrigation ditch with a TDS of 500 mg/1 and lower (although a slightly higher pH of 8.0 and <br />higher) has no detrimental effects on plants as witnessed by the success of irrigation in the area. <br />Since the early part of this century, it has been a regional practice to obtain water for irrigation <br />from the San Miguel River. Because of the incised nature of the drainage channels, it is difficult <br />to flood irrigate from them. From field reconnaissance investigations, no cases of water being <br />pumped from these draws for irrigation purposes has been discovered <br />Sub - irrigation A small amount of sub - irrigation does occur along the drainage channels. Much <br />of the ground water along these draws is a result of seepage through the weathered zone of the <br />bedrock from the irrigation ditches. In areas where the sub - irrigation occurs, the vegetation and <br />soil quickly dry up when the ditch is turned off from October to April. The sub - irrigation along <br />the drainage bottoms of the NHN permit area is not considered extensive enough to support <br />agricultural development. <br />Section 2.05.6(3) Page 10 October 2013 (TR -05) <br />E: \New Horizon \DRMS \NHN Permit \04_Technical Revisions TR \TR -05 \Documents from Jason \2.05.6(3) Protection of Hydrologic Balance_TR- OS.doc <br />