2017-02-03_PERMIT FILE - C1980004 (2)

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2.04.9 Soils Resource Information MAP UNIT DESCRIPTIONS MAP UNIT: AW - ALLUVIAL LAND, 0 TO 5 PERCENT SLOPES This map unit is on nearly level flood plains and stream channels. The slope is 0 to 5 percent. The native vegetation is mainly a g reasewood-sh ru bland community. These soils are mainly members of the mixed, frigid family of the Ustic Torrpsamments. Included in this map unit is about 10 percent Rivra gravelly sandy loam variant and about 5 percent Havre loam adjacent to stream bank. Included areas make up about 15 percent of the total acreage. Typically, the surface layer of the alluvial soil is a light brownish gray, loose, fine sandy loam about 2 inches thick. The substratum is stratified pale brown, single grained, very fine sand and medium sand about 48 inches thick. Permeability of the alluvial soil is moderately rapid. Available water capacity is moderate to moderately low. Effective rooting depth is 48 inches. Runoff is high and the erosion hazard for water is severe. Wind erosion hazard is high. The unit is mainly used for wildlife habitat. The present plant community is mainly greasewood, cottonwood, big sage, rabbit brush, burdock, gum weed, cheat grass, and western wheat grass. A representative profile of an alluvial fine sandy loam, sample point MU 15, 310 feet west and 20 feet north of the center of Section 29, T 7 S, R 102 W at an elevation o 5,250 feet is: Al 0 to 2 inches; light brownish gray (2.5 Y 6/2) fine sandy loam brown (10 YR 5/3) moist; weak very thin platy parting to fine single grained structure; loose, non - sticky, and non -plastic; calcareous; few fine roots; pH 8.3; gradual smooth boundary. CI 2 to 48 inches; pale brown (10 YR 6/3) stratified very fine sand to medium sand, brown (10 YR 5/3) moist; fine single grained structure; loose, non -sticky, and nonplastic; calcareous; few fine roots; pH 8.1. Sandstone bedrock is encountered below about 30 inches in some pedons. MAP UNIT: DL -DISTURBED LAND, VARIABLE SLOPES This map unit is on nearly level to very steep slopes. The slope range is 0 to 55 percent or more. The existing vegetation is mainly weeds and grasses. Typically, the surface layer of the disturbed soil includes some (20 to 35 percent) road fill material and averages about 4 inches thick but may range to 18 inches. Permeability of the disturbed soil varies from moderately low to high depending on compaction. Available water capacity is moderate to moderately low. Effective rooting depth varies with age of fill material. Runoff is moderate to very high and the PR -02 2.04-39 10/12