4202 CRESCENT AVE 2016-01-01 MF Import

i , 9ep 28 00 12t35p GEOTECH COHSULTHt1TS, IfiC. (4251747-8561 P•2 I �epecy pevefa�xrrenf JN 00376 September 27, 2000 Page 2 ; SUBSURPACE The subsurfa�x corxiitions vrere explored by axcavatlng three test pits at the appro�dmate locaations ahovm on thn Site Expbration P19n, Plate 2. Our expbratlon program was baaed on the Propo�ed conehvctio��, aMia�ated subsurface condidons and thoss encountered durinp exploratlon� and the scope af work outined in our proposal. The best pita were exc�vated on Septembar 21, 2000 wfth a t�ackhoe providad by the dierd. The underoigned Principal from our staA observed the excavation process and logged the test pits. Teat Pit 1, exa3vated near the northwestem side of fhe proposed residence, encouMered apProximately 2 feet of loae, siky sand with many roots overlying a wet, brown, soft to medium-atiff si't This s�t became atltf at approx(mately 5 feet, then hard and blue at approximately 8 feet. Te� Pit 2, expvated near tM norfheastem aide of the proposed . residence, encountered approximatdy 2 feet af laose topeoil overiyinp approximately 4 feet of loose, brorm, sandy siR. The siR becama Drey and dense at appro�mnately 6 faet Test Pit 3, excavated near U�e aoutheastem etde of the �esidence, e�couMered epproximotely 1 foot of topsoil overlying loose to medium-dense, brown, sflty eand. Thia aand became gray and dense a:approbmetely 4.5 feet. Groundwattr Condldiora Groundws�ter seepege was obaerved at a depth af appropmately 2 feet in Test Pit 2. Tha test pils were Ieft open for only a short time period. Thereforo, the seepage bvela on the bys roproserd the toeation ot transknt water seepage and may not indlcate the static groundwater level. It ahould be noted that yroundwater levels vary seasonaly with roinfail artd oU�er tadors. We arrtiapate that groundiwater eould be found in moro pertneable soil layers and between the near-surtace, loose soils and the undeAying denser sal. The compaetion of badcflll was not in the acope of our services. Loose sdl wiq theretore bo found in the area of the test pita. If tfiis pnaaents e probiem, the backfill w81 need to be removed and repleced with structural flli during Conatruc�ion. CONCLUSIONS AND RECOMMENDATIONS GENERAL the teat pits conducted for thia ahidy enc.rountered denselatifi, silty sand or aandy sik at a depN: of epprox6natety 4.5 to 8 feet. lriese soUa are suitabie to support the bu�Tding loads that are founded on comrenfional fooUngs, but some overexcavatlon ia needed on the towx portion of the proposed residence below the proposed footinp grade to roach these sofls. Thasa soBs aro very sensiitivve to moisture and are easily disturbad if wet. Some groundweter was encour�tered in Test Pit 2 on the lower portion of the site. If will iikely be necessary to cover the bearing eurfaces on the lower portion of the residence with 4 to 12 inches of imported, granular metetial to limit diaturbance to bearing soil, and it may be necessary in other areas as well. • Temporary cuts of 1:1 (HorizoMal:Vertical) are suitabfe for the si;d soils. We believe that temporary cuts on the upslope side of the residence made at this inrafnation will not extend near the sUeet above, and thus, it will not destabilize the street.