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Except for soil map units JO and 15, the soils are deep, well drained, and
<br />located on varying slopes, Permeability is slow to moderate and thus,
<br />surface run-off is moderate to rapid, Available water capacity is high and
<br />the effective rootiny depth is 60 inches or more, All of these soil units
<br />support habitat for mule deer, as well as ranye for livestock, and are
<br />utilized for some recreation.
<br />Soil types 4, 7U, and 75 are capable of heavy structure loading due to shal-
<br />low bedrock or a high rock content. The remaining soil types are suscepti-
<br />ble to shrinking and swelling, but are capable of supporting structures with
<br />proper desiyn and construction (U.S.D,A „ Soil Conservation Service, 1981).
<br />Soil types 3, 4, 5, and 70 are formed in cobbly and stony outwash from allu-
<br />vium derived from basalt. Types 22, 27, and 80 were formed on old landslide
<br />deposits and glacial outwash and on alluvial fans, terraces, and mountain-
<br />side slopes, Sail types 4, 22, 70, 75, and 80 are unsuitable for crops due
<br />to surface stoniness or slope, Though reclamation of these soils may be
<br />difficult, vegetation can be reestablished utilizing the appropriate seed
<br />mixtures, fertilizers, and mulch,
<br />Hydrology
<br />Field investigations conducted by CWI duriny June, 1983 and 1984, and a
<br />water rights investigation completed by HydroDynamics Inc. of Denver, Colo-
<br />rado for CWI in August, 1983, identified no groundwater resources within the
<br />transportation corridor, five intermittent drainages tributary to Steven's
<br />Gulch and the North Fork of the Gunnison River traverse the corridor in a
<br />northwest to southeast direction. These drainayes flow only in response to
<br />larye precipitation events, snow melt, and subsequent run-off,
<br />• In addition to the Fire Mountain Canal, the lower portion of the transporta-
<br />tion corridor is bisected by the John Beezley Ditch and the George W. Small
<br />Pipeline. The Canal and Ditch usually carry water from May to November for
<br />irrigation or other agricultural uses. The Pipeline carries water from
<br />springs within the Coal Gulch watershed for domestic and irrigation uses.
<br />Alluvial Vallev Floors
<br />Based on a study prepared by Geo-Hydro Consulting, Inc. (Geo-Hydro) of Den-
<br />ver, Colorado, for CWI in September, 1982, the Colorado Mined Land Reclama-
<br />tion Division determined the area bounded on the northwest by the Fire Moun-
<br />tain Canal and on the southeast by the North Fork of the Gunnison River to
<br />be an alluvial valley floor (AVF)(see Drawiny N10). This valley floor com-
<br />plex, called the North Fork AVF, includes terraces and alluvial and minimal
<br />colluvial deposits. The North Fork AVF was delineated primarily by land
<br />fornrs, but was further delineated by the historical use of the lands as
<br />flood irrigated orchards and pastures,
<br />A subsequent October, 1982, study, by Geo-Hydro presented plans for the
<br />restoration of the hydroloyic functions of the North Fork AVF - collecting
<br />water, storing water, reyulating the flow of water, and making water availa-
<br />ble (CMLRB Reyulations, 1981). After cessation of mininy operations at the
<br />Orchard Valley Mine, the surface facilities and structures will be removed,
<br />Paved and yraveled roads will also be removed and the train loadout area
<br />reyraded to restore surface drainaye patterns, Irrigation ditches, and the
<br />Farmer's Ditch in particular, will be restored to approximate pre-mining
<br />condition, Topsoil or conditioned subsoil will be replaced and orchards
<br />replanted in deliynated areas. For further information regarding the North
<br />Fork AVF, refer to CWI's Reclamation and Mine Plan, Permit No, C-038-83,
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