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The high permeability of the sandy soils and coarse colluvial <br />material in the fans adjacent to the ridge probably permit con- <br />siderable recharge from runoff which occurs from the north-facing <br />bedrock slopes of the hogback. However, the lack of significant <br />responses in downgradient wells and the dry upgradient monitoring <br />wells, suggest the entire area is underdrained by Colorado River <br />gravels or thick sections of coarse colluvial material. This <br />coarse material may be related to a paleochannel of the Colorado <br />River. Other evidence for this concept includes 1) lack of <br />significant groundwater to depths of at least 100 to 150 feet, 2) <br />poor quality, Mancos-like groundwater beneath the downgradient por- <br />tions of the facility area, 3) Mancos outcrop at and above river <br />level along most of this alluvial-colluvial area, and 4) lack of <br />any significant surface drainages from this portion of the ridge. <br />3.3.4.7 Springs and Seeps <br />The area within the permit boundary and adjacent land were surveyed <br />for spring and seep activity in June 1982 and June 1983. In <br />addition, low altitude infra-red color photographs were used to <br />identify potential spring areas which were later field-checked. <br />Two springs were identified during this process and a third was <br />identified from BLM records. The spring sites were visited and <br />appropriate field data recorded, including the geologic and <br />hydrologic characteristics. <br />Spring SP-1, located in South Canyon, appears to be seeping from <br />beneath the toe of a possible slump or old fill (Figure 3.3-6). <br />Since this spring has been monitored (Appendix 3.3-7), flow has <br />always been less than 1 gpm and is evaporated before reaching any <br />surface water body. The water quality of this spring places it in <br />the Mesaverde group as defined in Section 3.3.4.5, The actual <br />origin of this water is not known since it flows from beneath <br />colluvial material, however, a sandstone (Corcoran) is exposed <br />above this slump-like feature and may be the original source. <br />NCBC - Coal Ridge #1 3-33 n8C/1145/900301 <br />