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not to be Alluvial Valley Floors. The larger of the two areas totals 11.5 acres, but the residential <br />access road that passes over the area reduces the acreage to below 10 acres. <br />A third area identified as having alluvial deposits is located along the North Fork of the <br />Gunnison River. These consist of floodplain and low terrace alluvial deposits and are identified <br />as (Al) on Plate No. 2. This area meets the geologic and hydrologic criteria of an Alluvial Valley <br />Floor in having unconsolidated streamlaid deposits with water sufficient to sustain agriculture. <br />Portions of the loadout facility and rail spur have been part of the mine plan before August 3, <br />1977; therefore, their construction is grandfathered (see Alluvial Valley Floor Findings that <br />follow). <br />Adjoining these deposits on both sides of the river are deposits of coarse grained outwash <br />(pediment) labeled Qpc. Geomorphically the deposits form lobes and undulating topography <br />that extend down to the low alluvial terrace deposits of the identified Alluvial Valley Floor. <br />These deposits are easily identified on Map 8 -3 by the abrupt change in slope as one leaves the <br />floodplain and terrace deposits along the river. <br />The slope outwash deposits are flood irrigated, which meets the hydrologic criteria of an Alluvial <br />Valley Floor, but geologically they are mixtures of Mancos shale and eroded alluvium that were <br />primarily deposited by gravity flow and sheet wash. As such, they do not meet the criteria of <br />being stream laid. During the original review of the permit application, these deposits were <br />identified as part of the AVE But further review and interpretation of additional hydrologic and <br />geologic information during the summer of 1991 indicated that the area did not meet the strict <br />definition of an Alluvial Valley Floor. Deposits at the mouth of Steven's Gulch mapped as Qpc <br />on Plates 1 and 2, of the Geo -Hydro AVF Phase I study (Volume 4) are identified as slope <br />outwash deposits. As such, they also do not meet the strict definition of unconsolidated <br />streamlaid deposits. The U.S. Soil Conservation Service has identified the Aqua Fria soils in this <br />area as "Farmland of Statewide Importance" and not as prime farmland. <br />Because much of the area is occupied by flood irrigated orchards, the Division feels these areas <br />are worth protecting for their agricultural contribution. Although these areas are not AVF's, the <br />Division will require that these areas be treated as AVF's with respect to assuring that their <br />essential hydrologic functions be restored. On the basis of the information provided, the North <br />Fork of the Gunnison and its associated alluvium, identified as (Al) on Plate No. 2 in those <br />portions of Sections 29, 30 and 31 in T13S, R91W, and Section 36 in T13S, R92W, which lie <br />roughly between the Farmers Ditch and the North Fork of the Gunnison River, are Alluvial <br />Valley Floors. Slope outwash deposits and alluvial deposits located upslope (northwest) of the <br />Fire Mountain Canal did not meet the geologic and water availability criteria, and were given no <br />further consideration. The Alluvial Valley Floor along the North Fork continues downstream, as <br />shown on Map 5 -2. <br />The operator will be affecting 11.4 percent of the Terror Creek watershed. This area and the <br />adjacent Terror Creek were not considered in the Division's original Alluvial Valley Floor <br />determination August 20, 1981, but were considered during the review of the permit revision of <br />June 20, 1985. The operator did not identify any areas along Terror Creek that contain <br />significant bodies of alluvium. Most of the deposits are colluvial in nature and confined to the <br />immediate stream channel. The Morrell Camp area contains primarily colluvial deposits and as <br />such does not meet the definition of Alluvial Valley Floors. <br />Page 38 of 42 <br />