2505 PACIFIC AVE 2018-01-01 MF Import

,� _ Sierra Construction Services, Inc. JN 92276 July 1 , 1992 Page 3 The nine test borings encou�tered generally similar subsurface conditions. Typically, the borings revealed loose, silty sand fill or topsoil overlyi�g stiff to very stiff , native, clayey silts . Dense to very dense, silty sands were found to underlie the clayey silts. These sands contained relatively small emounts of gravel . The dense conditions of the native ' silts and the underlying silty sands indicates that theY were consolidated under the weight of past gleciers . Mottling of the silts implies that these soils have been weathered ' somewhat since they were originally deposited. Most of the explorations encountered 1 to 2 .5 feet of loose filt and topsoil immediately below the existing pavement or ground surface. Borings 4 , 7, and 10 encountered fill up Lo 7 feet in thickness , with the deepest fili revealed in eoring 7. This exploration was conducted in the area of fill that had previously been deposited on the site by Burlington Northern. The stiff to very stiff , native silts typically extended to a depth of 6 to 10 feet, before transitioning to the dense to , very dense sands . eorings 5 and 7 encountered the silt to . depths of 4 feet and 12 feet, respectivelY. No silt was encountered above t.he very dense sand in eoring 10. � The finel logs represent our interpretations of the field logs and laboratory tests . The stratification lines on the logs represent the approximate boundary between soil types at the exploration locetions . The actual transition between soil types mey be �radual and subsurface conditions may vary between exploration locations . If a transition in soil type occurred between samples in the borings , the depth of the trensition was interpreted. The relative densities and moisture descriptions indiceted on the test boring logs are interpretive descriptions based on the conditions observed , during drilling . The logs should be reviewed for specific subsurface informetion at the locations tested. GROUNDWATER Groundwater seepage was not observed in our explorations . 7he borings were left open only for a short time period, therefore, the lack of seepage levels on the logs does not necessarily indicate that �roundwater will not be encountered in the building excavations . It should be noted that groundwater levels cen vary seasonally with rainfall and other factors . we anticipate that some perched groundwater may be found between the loose, near-surface soils and the underlying , silt in wet weather . , GEOTECH CONSULTANTS , INC.