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EAHIBIT D-2 Page 5 3ci Ma~piny Un:;c 2: ;taddis'i-brown soild os~ 2h6 di'v y811evs r~_ Tnis mappi:c cnis a 1:~ Si;+Sa&; Paradox, Lisbon and Big Gypsum Valleys, snd Ury Creek Basin. It is not ~xtensiva but contains soils used for irrigation and these suitable for potential irrigation. '['ha iandsbapi: 'ac:+siats of long, narroa, gently sloping valleys that ere surrounded by steep slopes end cliffs. Each valley has a main intermit- tent drainageways wit: numerous qullied tributaries. Dry Creek Basin is n aide circular yalle:~ surrounded by rolling hills. All dteinageways are eroded to depths of IO to 30 feet and widths of 10 to 50 feet. Cover is domi++ately sagebrush with rabbitbrush, shadscele, greaseaood, and grass. This unit is composed of eboLt i5 percent reddish-b:o:rn, calcareous soils with light-colored surface layers that are low in organic matter. Surface layers and subsoils are moderately coarse tb moderately fine textured. Depths to underlying parent metarial ranges from 30 to more than 60 incFies. ~~+ost of these soils are suitable for irrigation. Runoff is .nediu~n. Trater holding capacities are moderate to high. About 20 percent of c~.e uni~c nos 5'.ayish-br~r.~, moderately fins and fine textured soils derived fi~.:..•iancc.s Shale. T'ne ~tganic matter consent is low and salinity is moderate: The aoiis ara cafe&reovs throughout the profile. ~anc;~'_ is rapid tnu the waiter erosion hazard is high. The remaining 5 yarc~:~t consists oi° shallow soils with gypsum shale or sandstone at fiepri+~ of 20 incnea or less. .Most of the gypsum is in the upper reaches of Peiradp;; and Big Gypsum Valleys. These soils have little vegetation and acre severely eroded. Runoff is rapid and the erosion hazard is high. Soii Mapping' i;t.l',: ~: iiccic o,acrsp and very shallow sails of the canyons Tnis mapping unit ~a a'loug the llolores and San Miguel Rivers and their sributaries. it is tiia ri,ost extensive unit and constitutes about one- ch:rci of the bbyin. :c~n:,ff is u•ery rapid because of the steep slopes end shallow soils whit luw water holding capacities. Sediment yield is from less than 0.2 to 1.J t,cre-fear per square mile per year. The landscapa.is characterized by deep sandstone canyons with steep slopes and long very narrow valleys, and floodplains. Small, gently sl~pinq mesas ara above the canyons. Steeply sloping alluvial fans border some of the canyon walls. Numerous intermittent drainageways dissect the steep slopes. The dominant cover is pinyon-juniper. Oak- brush, serviceberry, and grass are more abundant at higher elevations because of increased precipitation. Willows and cottonwood trees occupy small tracts along the narrow valleys. There are a few irtigated hay fields where the volleys ere wider.