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-16- <br />3) Alluvial gravels (Qag) divided into three (3) age categories (younger <br />(Qagy), middle (Qagm) and older (Qago)). The valley fill deposits are located <br />along the North Fork Valley side slopes. <br />CWI has identified alluvial/colluvial deposits in a second area which is <br />located along Steven's Gulch in the W 1/2 NW 1/4 of Section 13, T13S, R92W. <br />As identified in the CWI Phase 1 AVF Study, the area is approximately 20 acres <br />in size and is composed of valley-fill deposits (Qvf). The applicant can pump <br />30,000 GPD from a production well installed in this alluvium/colluvium, and <br />depth to water ranges from about 7 feet in May to approximately 36 feet in <br />February. The area is high and isolated, but has been used for pasture-hay <br />meadow. The area is not flood irrigated, has not been flood irrigated, and is <br />too high in elevation to be flood irrigated (at that elevation, the growing <br />season is too short for the normal flood irrigated crops). Subirrlgation is <br />limited to areas along the stream channel itself. The area is determined not <br />to be an alluvial valley floor based on its lack of flood irrigation potential <br />and lack of significant subirrigation. <br />An additional area along Steven's Gulch, within and to the south of the mine <br />permit area, contains areas of alluvium. This area includes the younger and <br />older alluvial gravel deposits in Sections 24 and 25 (T73S, R92W) and the W <br />1/2 of Section 30 (T13S, R91W). Four separate deposits have been identified <br />within this area, as shown on Map No. 2-2. The two larger deposits, labeled <br />Qagy and Qago, may meet the geomorphic criteria of alluvial valley floors, but <br />do not meet the water availability criteria for either flood irrigation or <br />subirrigation. Due to the steep slopes, rocky surface, and lack of sufficient <br />water, these areas are not capable of being flood irrigated. In regards to <br />subirrigation potential, the field investigation to detect subirrigated <br />species along Steven's Gulch did not identify arty such species within these <br />areas. Vegetation suggestive of subirrigation does occur along portions of <br />Steven's Gulch, but these species are confined to the extreme channel bottom <br />areas. Based upon this information, these two areas are found not to meet the <br />criteria for alluvial valley floors. These are older terraced deposits which <br />have been dissected by stream channels, such that the channels have completely <br />cut through the deposit. These areas are found not to be alluvial valley <br />floors. The larger of the two areas totals 17.5 acres, but the residential <br />access road which passes over the area reduces the acreage to below 10 acres. <br />A third area identified as having alluvial deposits is located at the mouth of <br />Steven's Gulch and along the North Fork of the Gunnison River. Low terrace <br />deposits along the river are identified as to be alluvial valley floors, but <br />the designation of deposits in the upper part of the area is questionable. <br />Deposits at the mouth of Steven's Gulch mapped as Qpc on Plates 1 and 2, of <br />the geohydro AVF Phase I study N olume 4) are identified as slope outwash <br />deposits. As such, they do not strictly meet the definition of unconsolidated <br />stream laid deposits. On the other hand, since they are located within the <br />flood plain-terrace complex, they cannot be eliminated as upland deposits. <br />Since these deposits fall into neither category, the appropriate AVF <br />designation is unclear. However, because much of the area is occupied by <br />flood-irr gated orchards, the Division feels these areas of the state are <br />worth pro ecting for their agricultural contribution and are therefore <br />determined to be Alluvial Valley Floors. On the basis of the information <br />provided, the North Fork of the Gunnison and it's associated alluvium in those <br />portions of Sections 29, 30 and 31 in T13S, R91W, and Section 36 in T13S, R92W <br />