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Subsurface Exploration and Foundation Evaluation Proposed Golden Oil Refueling Station Stoughton, Wisconsin PSI Project No. 0092822 Page 4 with a calibrated hand penetrometer to aid in evaluating the soil strength characteristics. The values of strength tests performed on soil samples obtained by the Standard Penetration Test Method (SPT) are considered approximate, recognizing that the SPT method provides a representative but somewhat disturbed soil sample. The laboratory testing was performed in general accordance with the respective ASTM methods, as applicable, and the results are shown on the boring logs in the Appendix. DESCRIPTION OF SUBSURFACE CONDITIONS General A description of the subsurface conditions encountered at the test boring locations is shown on the Soil Boring Logs. The lines of demarcation shown on the logs represent approximate boundaries between the various soil classifications. It must be recognized that the soil descriptions are considered representative for the specific test hole location, but that variations may occur between and beyond the sampling intervals and boring locations. Soil depths, topsoil and layer thicknesses, and demarcation lines utilized for preconstruction planning should not be expected to yield exact and final quantities. A summary of the major soil profile components is described in the following paragraphs. Soil Conditions The surface at B-2 through B-5, and B-7 consisted of about 2 to 8 inches of brown to black silty clay or sandy silt, classified as topsoil or topsoil fill. The surface at B-1 and SW-2 consisted of about 12 inches of sandy gravel to gravelly sand fill. At B-6, the surface consisted of 3 inches of asphalt pavement underlain by 3 inches of base course. The surface materials at SW-1 consisted of 3 inches of asphalt pavement underlain by 4 inches of concrete. The surface materials at B-1, B-2, B-3, B-6, SW-1, and SW-2 were underlain by fill and possible fill to depths ranging from about 6 to 8 feet (EL. 867.0 to EL. 869.1) below the surface. These materials were somewhat variable in composition, consisting of sandy gravel, silty clay, loamy sand, and loam. At B-6, the fill was underlain by black silty clay classified as possible buried topsoil to a depth of about 8.5 feet (EL. 864.7). The underlying natural soils at these borings, and those beneath the surface materials at the remaining locations generally consisted of tan to brown silty sand; brown to gray sandy gravel; brown silty clay; and gray to black loam. The natural cohesive soils were generally soft to stiff in comparative consistency, with unconfined compressive strength estimates typically between about 0.75 to 2.00 tons per square foot (tsf). The natural granular soils encountered were loose to dense in relative density, with N-values typically between 9 bpf and 40 blows for 1 inch of sampler penetration. The fill, possible fill, and possible buried topsoil materials were classified as such based on their varied visual characteristics and composition. However, it must be recognized that in the absence of foreign substances and/or debris within the soil samples obtained, it is often difficult to distinguish between natural soils and clean soil fill.