2007-09-11_REVISION - M1997054 (2)

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This soil is mazginally suitable for salvage to an average depth of 9" due to the high coarse fragment content. Deeper salvage is restricted by the presence of bedrock. As with the soil of Map Unit B salvage of this soil will be difficult considering operational and safety factors. The soil occurs in a mosaic pattern with rock outcrops, surface rock exposures, tree stands, and very shallow soils. Both collection and transport of soils to stockpile areas will likely be inefficient. Salvage operations may occur opportunistically over this unit with the lower slope positions potentially supplying the majority of the volume of soil available for salvage. Map Unit D Gravel Pit and Plant Areas To complete sampling, the proposed addendum area of Map Unit D was viewed to become familiar with access routes and surficial soil conditions characteristic of the site as influenced by topography, vegetation, and geology. The area was divided into two "blocks" within which sampling was completed. Ave sub-samples were taken along each transect representing the surficial soil material from 6 to 18 inches in depth depending upon soil profile conditions. The subsampies were then composited for shipment to the Plant Testing Laboratory on the Colorado State University campus for analysis of ph, texture (field method), percent organic matter, NH4- N and N03-N (ppm),phosphorus (ppm),potassium (ppm), electrical conductivity (mnilios/cm), lime estimate, and micro-nutrients (ppm). Map Unit D soils (sample S-5) overlie a nearly level, slightly convex gravel bar bordering Tallahassee Creek. Coazse soils ranging from 6-12"+ deep overly approximately 60% of this unit. The remaining 40% of the unit consists of coarse soils less than 6" deep to a cobble layer and acobble/rock deposit at the surface. Block 1 soils (Kim barns) occur on a southeast aspect at slopes less than or equal to 1%. These soils appear to have been flood irrigated in the past but have not been cropped recently. Some limited imgation may have occurred in combination with grazing activities. surficial soil cover over this block averaged 45% vegetation, 25 % coarse fragments, 10 % litter, and 20 % bam ground. Depths to high coarse fragment layers of the soil profiles ranged from 6 to 18 inches, with the shallowest depths associated with the southern portions of the block and the deepest with the northern portions of the block. Coazse fragment percentages of the upper soil horizons (6 to 18 inches) did not exceed 10 percent by volume. The dominant soils of Block 1 have a sandy day loam texture, a pH of 8.0. and an electrical conductivity of 0.4 mmhos/cm. All micro-nutrient levels aze within acceptable limits. Therefore, this soil is of an acceptable quality for salvage and reapplication to azeas to be re-investigated. Given the range to depths (6- 18 inches) to a high coarse fragment layer, this soil is assumed to be salvageable to an average depth of 12 inches over the Block 1 portion of the addendum area. Block 2 soils, also dominated by the Kim loam series, parallel those of Block 2 in terms to land use, slope. and aspect. In addition, there are few differences in surficial soil cover percentages of vegetation, coarse fragments, and litter. Depths to soil layers with high coarse fragment contents also range from 6 to 18 inches with the deepest depths found in the northern portion of the block. The percent of coarse fragments in the surficial soil horizons, by volume, is equal to or less than 10 %. The dominant soil of Block 2 has chemical and physical characteristics closely paralleling those of the dominant soil of Block 2. The most notable exception to this is the somewhat elevated Front Range Aggregates, LLC- Parkda[e Quarry DMC 112 PermifAmendmenf Page 40