2008-08-19_PERMIT FILE - C1996083A (5)

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• Soils Report, Bowie Area 12/4/00 An area near Bowie, Colorado was surveyed for soil depths and samples were taken for subsequent analysis on October 26, 2000. The southern portion of the area is planted to apples, and the northern portion is in an otd stand of alfalfa. The east is bordered by a railroad bed, and the west is bordered by a roadway. Two holes at each location indicated on the accompanying map*were examined for depth and horizon presence. The depths were averaged together at each of the locations. The holes were augured with a 4" bucket soil augur to the point where extensive rock gravels were encountered. The loose rock horizon was considered to be the "C" horizon. The areas have been tilled and irrigated over the years, so no apparent Ao was observed. However, a distinct Al horizon as well as a B horizon was present in all holes. The B horizon grades into an unconsolidated C horizon consisting of mostly loose granitic and some sandstone rock. The area had been irrigated with a surface furrow design irrigation water out of a ditch at the head end of the field. The apple trees appeared to be in good health, but the alfalfa field was somewhat neglected. The area slopes quite severely to an existing railroad bed. In all cases, the depths were least at the head (west) end of the field and deepest toward the tail end of the field. Table 1 presents the depths of the soil at the 10 locations. Through the years, the soil was probably deposited and eroded to yield the different depths, and as a result of the slope, explains the deeper horizons at the east end of the field. The samples were combined in the following manner for physical and chemical analyses: Holes 1 and 2 were combined in both the A and B horizons to yield a sample for the A and the B horizons respectively; holes 3 and 4 were combined in the same manner; and, etc. to yield 10 samples, 3 A horizon and 3 B horizon samples from the orchard area and 2 A horizon and 2 B horizon samples from the alfalfa area. The soil samples were air-dried, subjected to particle size determination and finally ground to pass through a 2 mm sieve. The sieved samples were subjected to saturated extraction for salinity characteristics. Table 2 presents the salinity characteristics of the soils. The pH, electrical conductivity and Sodium Adsorption Ratio (SAR) were determined from saturated pastes and their extracts of the soils. The pH's of all samples are at or slightly above neutra{ity, and the salinity contents of them are negligible. A conductivity above 3.0 decisiemens per meter is considered to represent a saline soil; all of the soils contained a salt content indicated by less than 0.75 decisiemens per meter. Also, the SAR's of the soils indicate that they have essentially no sodium hazard associated with them. An SAR greater than 15 is indicative of a sodium problem in *See permit Map 4 Soils Pz-6 ~ P~,eot,~ ~/~s~a Z