Laserfiche WebLink
� KA No. 092-06160 <br /> October 7.5,2006 <br /> Page 3 <br /> encountered during the cnnstruction phase of the project. The e�•aluation of such far�ors is beyond the <br /> scope of this report. <br /> Seismic Conditinns <br /> 'i�he g(acial soils eacountered in thc exploratory borings, p;imarily below a depth of ahout LS to 35 fce!. <br /> wcre gcncrally medium dense to very dense. Thc evcrall soil profile generally corresponds to a site class <br /> soil profile of C as dcfincd by 'I'able 1615.1.1 of the 2003 Interratim�al Building CnJe (IBC). A site <br /> class soil profile ef C npplies ro a profile corsisting primarily of dcn:>e to very den,e soils within the <br />' upper 100 feet. <br /> CONCF.USiONS AND RGCO�IMENDA'fIONS <br /> Gencral <br /> B�sed on the findings of this invcstigation and prcvious geotecnnical expericnce in the project arca, it is <br /> our opin+on tliat tt�e proposed addition may be supported on a shallow foundation system bcaring on thc <br /> mcdium dense to dcnse native soils or on properly compacted, stn�ctural fill, placed on the mcdium <br /> densc to dcnsc naiivc soils. <br /> If loose native soi!s and/or undocumcnted fill is encountered at footing gradcs, rccommcndations for <br /> overexcavation and/or re-compaction will be provided at[he time of the site inspection work. <br /> Site Nreparntion <br /> General site clearing should includc rcmoval of vegetation; trees and ussociatcd root systems; wood; <br /> existing utilities; structures inclurling foundations, basement walls and floors; undocumentcd fill,rubble; <br /> and rubbish. Site sttipping should inclutic the removal of the undocumentcd fill matcrial within thc <br /> proposed addition area(approximatcly 2.5 to 3.5 feet, preliminary bascd on our test pit locations). Tltese <br /> materials will not be suitable for usc as structural fill. However, stripped topsoil may be stockpiled and <br /> reused in laadscape or non-structural areas. <br /> Aftcr stripping operations and removal of any undocumen[ed till, the building pad areas should bc <br /> visually inspected to identify any loc�se arcas. My rcmaining loose soils should be ovcrcxcavatcd to thc <br /> Icvcl of the medium dense to dcr.se, nativc soils. The resulting excavations should bc fillcd with <br /> approvcd on:�ie material, or importcd structural fill. Stntctural fill material should bc within t 2 perccnt <br /> of thc optiraum moistur� content, and the soils should be compacted lo a minimum of 95 perecnt oP the <br /> maximum dry density hased on AST�I Test Mcthod D1557. <br /> Uurirg�vet wcather conditions, lypically October Qvough 1v1ay, subgradc stabiliry problems and grading <br /> difficulties may devclop duc to cxcess moislure, disturUance of scnsitive soiis and/or the presence of <br /> perched groundwater. Construction during the extended wet weatuer periods could crcate thc need to <br /> ovcrcxcavatc cxposed soits if thcy bccome disturbed and cannot be recompactcd duc to clevatcd <br /> moisture contents. Although ti�e on sitc nativc soils are grave?ly, they may have variable silt contents <br /> and may bc moisture sensitive. If ovcrcxcavation is necessary, it should be confirmed through <br /> continuous monitoring and testing by a yualificd gcotcchnical engi7eer or senior geologist. Soils that <br /> have become unstable may require drying and recompaction. Selcctive drying may be accomplished by <br /> scarifying or windrowing surficial material during extendc� periods of dry, wartn weather (typically <br /> Krezen&Assoclatcs,Ine. �� <br /> Offices Scrving The�Vestem Uaited Smtcs �1 � <br /> ..` <br />