1919 112TH ST SW 2016-01-01 MF Import

March 24 1994 ]1 943-]525 encounter any large cobbles or bouldprs in the till, however, we commonly observe them in till on other sites. � �il� - This unit was encountered in all the test pits and catended the full depth of our explorations. It had essentially the same grein size distribution as the weathered till, however it was typically denae to very denae, sometimes requiring exceptional effort to ezr.avate. In general, lenses of sand are common in till, and these lenses can hold groundwater. Typically the lenses are of limited extent and seepage from them decreases with time. A sand lens containing water was possibly fhe source of the seepage observed in 'IP-1 and TP-2. 4.3.2 Groundwater We encountered groundwater seepage in only two of our test pits, TP-7 and T['-2 during our investigaHon on March 8, 19�M. The seepage in TP-1 was observed at a depth of about 11 feet. The seepage was slight, and not of sufficient flow to wet the bottom of the test pit. In TP-2, seepage was observed in a zone from about 7 to ?3 feet. Slight caving of the sidewalls oE the test pit were observed. The (low rates were slightly higher than obaerved in TP-1, a��d about three inches of water ponded at the bottom of the test pit during the time the test pit was open. Groundwater elevations fluxuate at different times of the year and with rainfall evenL. The groundwater conditions described here are only for the time and locations described. These conditions could change over time. 4.4 Rernmmendatlone and Conclusions '� 4.4.1 Foundatlone Shallow conventional spread footings may be founded on the compact to dense nalive soils � or compacted structural fill placed on the mentioned native soils. Footings should not be , founded on disturbed, loose, saturated, organic rich soils, or fill. Building foundations should be designed and constructed based on the following parameters. Minimum Lateral Dlmeneione Isolated Spread Footings 21 inches Continuous Spread Footings 18 inches Minimum Depth of Embedment Depth below lowest adjacent grade: Exterior Footings Interior Footings Golder Associ3tes ]8 inches ]2inches