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. Subsurface Conditions: The subsurface conditions along the proposed roadway alignments were investigated by drilling six (6) test holes at the approximate locations shown in Figure #2. The subsurface conditions encountered in existing roadway azeas (test holes 1, 5 and ~ were variable and generally consisted of a layer of road base sands and gavel fill materials overlying a mixmre of clay, silt and sand fill materials to the maximum depth explored, 6 feet. The subsurface conditions encountered in test holes 2, 3 and 4 generally consisted of a layer of topsoil and organics overlying either fill materials or natural clays and sands or sands and silts to the maximum depth explored, 10 feet Graphic logs of the exploratory test holes are shown m the attached Figure #3 and the associated Legend and Notes aze presented in Figtue #4. A layer of toad base sand and gavel fill materials was encountered at the Bound surface in test holes I, 5 and 6 and vazied from 12 to 24 inches in thickness. The sand and gave] fill materials were slightly silty to sihy, fine to coarse gained, non-plastic, dense, dry and dark brown to brown in color. Samples of the sands and gavel fill materials classified as SM-GM and GP soils in accordance with the Unified Soil Classification System. Man-made fill materials were encountered beneath the read base sand and gavel fill materials in test holes I, 5 and 6 and beneath the topsoil and organics layer in test hole 4. Tbese fill materials consisted of a mixture of clays, silts and sands that were ]ow to non-plastic, fine to coarse gained, stiff to very stiff, slightly moist io moist and brown in color. Samples of the fill materials classified as SM to SM-ML soils in accordance with the Unified Soil Classification System, A layer of topsoil and organic materials was encountered at the ground surface in test holes 2, 3 and 4 and varied from 1'J, to 3'h feet in thickness. Natural clays ands sands were encountered beneath the topsoil and organics layer • in test hole 2 and extended to the maximum depth explored. The clays and sands were low to moderately plastic, fine grained, stiff to dense, dry to moist and bluish gay to brown in color. A sample of these soils classified as an SC soil in accordance with the Unified Soil Classification System. Namral sands and silts were encountered beneath the topsoil and organics layer in test hole 3 and benead the fill materials in test hole 4. The sands and silts were fine gained, very low to non-plastic, medium stiff to dense, dry to moist and brown in color. A sample of these soils classified as a ML-SM soil in accordance with the Unified Soil Classification System. A swell-consolidation test conducted on a sample of the very clayey sands exhibited a low swell potential when wetted under a constant load. However, the sample also exhibited a moderate to high consolidation potential under relatively light loading conditions prior to wening. The swell-consolidation tests conducted on samples of the natural silt and sand, and the silty sand fill materials exhibited no swell potential when wetted under a constant load and only a slight degee of consolidation when loaded. The swell-consolidation test results are shown in Figures #5 through #7. The gadation test results conducted on samples of the road base sand and gravel fiil materials ere shown in Figures # 8 and #9. All of the laboratory other test results are summarized in the attached Table 1. Groundwater seepage was not encountered in any of the test holes at the time of drilling. It should be noted that the groundwater conditions at the site can be expected to fluctuate with changes in runoff and precipitation at the site, Roadu•av Construction Recommendations: Based on the subsurface conditions encountered in the test holes and the proposed construction, we recommend that the unrctained cut slopes constructed for new roadway in Option #1 • Job Number: 01.6618 h'WCC, inc. Paget