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-16- 3) Alluvial gravels (Qag) divided into three (3) age categories (younger (Qagy), middle (Qagn) and older (Qago)). The valley fill deposits are located along the North Fo-k Valley side slopes. CWI has identified alluvial/colluvial deposits in a second area which is located along Steven's Gulch in the W 1/2 NW 1/4 of Section 13, T13S, R92W. As identified in the CWI Phase 1 AYF Study, the area is approximately 20 acres in size and is composed of valley-fill deposits (Qvf). The applicant can pump 30,000 GPD from a production well installed in this alluvium/colluvium, and depth to water ranges from about 7 feet in MAy to approximately 36 feet in February. The area is high and isolated, but has been used for pasture-h AY meadow. The area is not flood irrigated, has not been flood irrigated, and is too high in elevation to be flood irrigated (at that elevation, the growing season is too short for the normal flood irrigated crops). subirrigation is limited to areas along the stream channel Itself. The area is determined not to be an alluvial valley floor based on its lack of flood irrigation potential and lack of significarrt subirrigation. An additional area along Steven's Gulch, within and to the south of the mine permit area, contains areas of alluvium, This area includes the younger and older alluvial gravel deposits 1n Sections 24 and 25 (T13S, R92W) and the W 1/2 of Section 30 (7135, R91W). Four separate deposits have been identified within this area, as shown on Map No. 2-2. The two larger deposits, labeled • Qagy and Qago, may meet the geomorphic criteria of alluvial valley floors, but do not meet the water availability criteria for either flood irrigation or subirrigation. Due to the steep slopes, rocky surface, and lack of sufficient water, these areas are not capable of being flood irrigated. In regards to subirrigation potential, the field investigation to detect subirrlgated species along Steven's Gulch did not identify orb such species within these areas. Yegetation suggestive of subirrigation does occur along portions of Steven's Gulch, but these species are confined to the extreme channel bottom areas. Based upon this information, these two areas are found not to meet the criteria for alluvial valley floors. These are older terraced deposits which have been dissected by stream channels, such that the channels have completely cut through the deposit. These areas are found not to be alluvial valley floors, The larger of the two areas totals 11.5 acres, but the residential access road which passes over the area reduces the acreage to below 10 acres. A third area identified as having alluvial deposits is located at the mouth of Steven's Gulch and along the North Fork of the Gunnison River. Low terrace deposits along the river are identified as to be alluvial valley floors, but the designation of deposits in the upper part of the area is questionable. Deposits at the mouth of Steven's Gulch mapped as Qpc on Plates 1 and 2, of the geohydro AVF Phase 1 study N olume 4) are Identified as slope outwash deposits. As such, they do not strictly meet the definition of unco.~solidated stream laid deposits. On the other hand, since they are located within the flood plain-terrace complex, they cannot be eliminated as upland deposits. Since these deposits fall into neither category, the appropriate AVF designation is unclear. HoMever, because much of the area is occupied by . flood-irrigated orchards, the Division feels these areas of the state are worth protecting for their agricultural contribution and are therefore determined to be Alluvial Valley Floors. On the basis of the information provided, the North Fork of the Gunnison and it's associated alluvium in those portions of Sections 29. 30 and 31 1n 7135, R91W, and Section 36 in 7135, R92W