4020 COLBY AVE Geotech Report 2018-01-02 MF Import

,..� - McDonald's Corporation E-3G7G December 21, 1987 Page 3 the locations. Please refer to the boring logs, P13tes 4 through 8, for a detailed description of the conciitions encountered at eac� location explored. A Rescription of the field exploration me�hods and laboratory testing program is included in this report following the Discussion and Recommendations section. The following is a generalized description of the subsurface conditions enceuntered. The upper two to three feet consist of topsoil, sod, and loose brown sand. The surficial soils are underlain by medium dense to very dense sandy till. The iill is an over-consolidated homogeneous mixture of silt, sand and qravel. The till also contai.ns lenses and stringers of sand. The till is underlain by nedium dense to dense silty sand, with gravel in all borings except Boring B-2 . Groundwater Groundwater was not observed while drilling. Fiowever, some seepaqe may be expected during the rainy season into excavations from the sand lenses and perched groundwater on top of the till or from sandy zones within the till. The groundwater seepage is not static, thus ane may expect fluctuations in seepage rates depending on the amount ��f rainfall, snrface water runoff, and other factors. Generally the water level is higher in the wetter winter months. DISCIJSSION AND RECOMMENDA'I'IONS General The purpose of this study is to providE an evaluation of soil conditions in the development area as they pertain to soil bearing for foundation, drainage, and other construction related elements. In the preceding description of site conditions it has been noted that six (6) to twelve (12) feet of soil are to be removed from the site. The McDonald's store would then be founded on medium dense to dense silty sand or dense till. The proposed structure may be supported on conventional footings bearing on these dense native granular soils. Concrete slabs and asphalt pavements may be supported on at least one foot of recompacted native soils. To prevent subgrade distur- bance during the wet winter months by construction traffic, the entire site should be covered with crushed rock or Asphalt Treated Base (ATB} . In lieu of coverinq the site, the parking and slab area could be left five to six-tenths of a foot high and then brought to the correct elevation just prior to paving oY� concrete placement. Earth Consultants. Inc.