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I The Soil Conservation District (SCD) and the Agricultural Stabilization and Conservation Services (ASCS) at Walsenburg were consulted on agricultural practices along valley floors in ttie region. Xerox copies were obtained of 2 the soil classification map (Figure W.06.8-1) and explanatory notes of the 2 soil classification system (Tables yt..06.8-1 and -2) pertaining to the Pryor Mine area. Inspection o` aerial photographs covering the Santa Clara Creek and the entire length of the Black Hawk Canyon showed no farm land, However, along parts of Walsen Arroyo (Figure 2.04.5-1) to the north of the Pryor Mine area, some signs of agricultural activity were observable in the aerial photos. Walsen Arroyo is an ephemeral stream like 5arta Clara Creek but flows through more gently sloping topography and has a wider and more open valley which probably makes it more suitable for flood irrigation, According to accounts by 14r, Samuel J. Capps, a local farmer at Pryor, irrigation was also practiced along Santa Clara Creek downstream from the confluence with Pryor Canyon about 30 to 40 years ago. Remnants of the diversion structure and concrete lined canal still stand on a 40 feet high waterfall across Santa Clara Creek northeast of the Pryor General Store. Initially', only creek water was used to irrigate the fields for alfalfa and hay, The volume was, however, insufficient and it was supplemented with water from the mines. After two years, the land was rendered useless and the whole project abandoned apparently due to salt deposits from the mine waters. Our findings on the reconnaissance investigation of probable alluvial valley floor in and adjacent to Pryor Mine Permit Area are summarized below: 1. from surface water and ground water adjacent area considerations, the Black Hawk Canyon has the mast probable alluvial valley floor. 2. The Black Hawk Ca~iyon alluvial valley floor meets the geomorphic characteristics. It has channel width, bankful width, bankful depth, valley floor width and total area exceeding the minimum specified in the Alluvial Valley Floor Guidelines. 3. The Black Hawk Canyon alluvial valley floor does not fulfill the water availability criteria. It is a dry creek with no seeps and no historical or present evidence to show flood irrigation practice. Moreover, flood irrigation would be impractical not only due to the deeply incised channel but also because of past mine voids that evidently underly parts of the valley floor and have presently created subsidence structures on the valley floor. 358. JFSA - 72 J. F. SATO & ASSOCIATES, INC.