2007-09-11_REVISION - M1997054 (2)

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Map Unit A Granite Quarry and Plant Area Map Unit A is a convex valley/fan complex influenced by alluvial and colluvial action. The lower, eroded toe slopes of Map Unit C are included in this unit due to salvage considerations. Approximately 90% of this unit, where disturbance is proposed to occur, consists of the soil represented by sample S-2. This soil is approximately 40" deep to a hazd layer impenetrable by a hand auger. The surface 18" of this soil has a very gravelly sandy clay loam texture and a pH of 8.2 with electrical conductivity of 0.4 mmhos/cm. Coazse fragment, or gravel, content of the soil to this depth is estimated to be 50%. Five percent of the area potentially to be disturbed consists of the soil represented by sample S-1 which occurs immediately adjacent to Tallahassee Creek. This soil is 60" deep and typically has a loamy sand to sandy loam texture, a pH of 8.2, and an electrical conductivity of 8.0 nunhos/cm in the upper 18" of the soil profile. There is less than 5% coarse fragments (gravel) throughout the profile. The remaining 5% of this unit consists of drainages and rock outcrops located along the foothill toe slopes, These soils are suitable for salvage to a depth of 18" over 95% of the unit. The remaining 5% of the unit is not overlain with salvageable soils, Due to its proximity to the banks of Tallahassee Creek, the soil represented by sample point S-1 would not be disturbed to any great degree. If salvaged, this soil would be sufficiently diluted to eliminate the negative effects of the higher electrical conductivity value. Map Unit B Sandstone Quarry Area An existing abandoned sandstone quarry and associated undisturbed rocky soils on convex, moderately steep sideslopes make up this unit. Of the area proposed to be disturbed, approximately 66% consists of rock outcrops, surface rock exposures, and soils less than 6" deep to bedrock. Shallow soils to a depth of 9" to bedrock (sample S-3) occur over the remaining 33% of the area proposed to be disturbed. This shallow soil typically has a gravelly sandy clay texture, a pH of 8.1, an electrical conductivity of 0.4 mmhos/cm, and exhibits approximately 35% coarse fragments (gravel) throughout the profile. Though suitable to marginally suitable for salvage (in terms of chemical and physical characteristics} to a depth of approximately 9", salvage of this soil over the portion of the disturbed area where it occurs will be difficult. Salvageable depths occur in a mosaic with rock outcrops, surface rock exposures, tree stands, and very shallow soils making salvage operations potentially problematic, especially in terms of stockpiling. Soil salvage will also be compromised due to safety issues surrounding soil location near natural highwalls. Proximity of the Salvage of this soil should be considered opportunistic with the volume available for stockpile and reapplication uncertain. Map Unit C Granite Quarry Area This unit occurs on steep, concave-convex, foothill sideslopes. Approximately 75% of the unit consists of rock outcrops, surface rock exposures, incised drainages between bedrock outcrops, and soils less than 6" deep to bedrock. Shallow soils ranging from 6 to 12" deep to bedrock (sample S-4) occur over the remaining 25% of the area proposed to be disturbed. This shallow soil typically has a very gravelly sandy clay texture, a pH of 8.2, and an electrical conductivity of 8.2 mmhos/cm. Approximately 50% coarse fragments (gravel) occur throughout the profile with coarse fragment content decreasing as elevation increases. Fr¢nt Range Aggreg¢les, LLC- Parkdale Quarry DMG 111 Permit Amendment Page 39