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Adjoining these deposits on both sides of the river are deposits of coarse grained outwash <br />(pediment). Geomorphically, the deposits form lobes and undulating topography that <br />extend down to the low alluvial terrace deposits of the identified Alluvial Valley Floor. <br />The slope outwash deposits are flood irrigated, which meets the hydrologic criteria of an <br />Alluvial Valley Floor, but geologically they are mixtures of Mancos shale and eroded <br />alluvium that were primarily deposited by gravity flow and sheet wash. As such, they do <br />not meet the criteria of being stream laid. During the original review of the permit <br />application, these deposits wore identified as part of the AVF. But further review and <br />interpretation of additional hydrologic and geologic information during the summer of <br />1991 indicated that the area did not meet the strict definition of an Alluvial Valley Floor. <br />Deposits at the mouth of Steven's Gulch mapped as Qpc on Plates 1 and 2, of the <br />Geo -Hydro AVF Phase I study (Volume 4 of the PAP) are identified as slope outwash <br />deposits. As such, they also do not meet the strict definition of unconsolidated stream -laid <br />deposits. The U.S. Soil Conservation Service has identified the Aqua Fria soils in this area <br />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 <br />areas are worth protecting for their agricultural contribution. Although these areas are not <br />AVF's, the Division will require that these areas be treated as AVF's with respect to <br />assuring that their essential hydrologic functions be restored. On the basis of the <br />information provided, the North Fork of the Gunnison and its associated alluvium, <br />identified as (Al) on Plate No. 2 of the PAP in those portions of Sections 29, 30 and 31 in <br />T 135, R91W, and Section 36 in T 135, R92W, which lie roughly between the Farmers <br />Ditch andthe North Fork ofthe Gunnison River, are Alluvial Valley Floors. Slope ouMash <br />deposits and alluvial deposits located upslope (northwest) of the Fire Mountain Canal did <br />not meet the geologic and water availability criteria, and were given no further <br />consideration. T he Alluvial Valley Floor along the North Fork continues downstream, as <br />shown on Map 5-2 of the PAP. <br />The operator will be affecting 11.4 percent of the Terror Creek watershed. This area and <br />the adjacent T error Creek were not considered in the Division's original Alluvial Valley <br />Floor determination August 20, 1981, but were considered during the review of the permit <br />revision of June 20, 1985. The operator did not identify any areas along Terror Creek that <br />contain significant bodies of alluvium. Most of the deposits are colluvial in nature and <br />confined to the immediate stream channel. The Morrell Camp area contains primarily <br />colluvial deposits and as such does not meet the definition of Alluvial Valley Floors. <br />East and West Roatcap Creek were also not determined to be Alluvial Valley Floors. The <br />sediments are predominately colluvial in nature and are too limited to support agricultural <br />activities. <br />In reviewing the original application, some concernswere raised over whetherthe applicant <br />proposed to use augmentation water that would normally supply an AVF. The applicant <br />responded by showing that T error Ditch and West Reservoir waters supply Garvin Mesa <br />and an irrigated area known as "The Basin," both of which are out of the valley floor <br />41 <br />