4805 BELVEDERE AVE 2016-01-01 MF Import

Su6turface Exploration, Geologic Haznrd, and Uelvedere Lots Easr Preli�ninary Georechnical Engineering Report Eurett Wnshingm�� Prr(iminan Design Rrcommendariorts building construction near the top of the steep slope, we recommend that building construction be limited to the portion of the site at or behind the top of the steep slope, with special Coundation design criteria recommended for building construction within 40 feet of the top of the .:ep slope. The top of the steep slope is depicted on the Site and Exploration Plan, Figure 2. lt should be noted that the top of the steep slope as shown on Figure 2, represen;s the top of the portion of the slope that is equal to or greater than 40 percent grade and gre:.ter than ]0 feet in ��ertical height. Recommended landslide hazard mitigation, based on building location relative to the top of the slope, is summarized in Table 2, previously presented in the Landslide HaZords and Afitigotions section of this report. �pecific recornmendations for foundation design are provided below, organized by distance from Ihe top of the slope. 1 l. l Foundation Recommendations for Structures Located Greater than 40 Peet from the Top of the Steep Slope Fur structures located at least 40 feet back from thc top of the steep slope, convent�onal spread footings may be utilized for building support when founded either direcdy on the medium dense to densc n�mtal sediments or on structural fill placed over diesz materials. We recommend that an allowablc foundation soil bearing pressure of 2,OW pounds per square foot (ps� be utilized for design purposes, including both dead and live loads. An increase of one- third may be used for short-term w�ind or seismic loading. In those ar:as where (o�tings will bear direcdy on the medium dense to dense natural sand, the sand below the footings should hc compacted to � firm, unyielding condition prior to footing placement. The area of compacti��n should exccnd at lcast 1 foot beyond the footing edges. Perimeter footings for [he propo�rJ buildings should be buried a minimum of 18 inches into the surrounding soil fot frust ��rotection. No minimum burial depth is rcyuired for interior footings; howcver, all footin!�s must penetrate to the prescribed stratum and no footings should be founded in or abo��e lonse, nrganic, or existing fill soils. It should bc notcd that the arca bound�d h�� lines extending do�+�m��ard at 1H:1V from an)' fuoting must not interscc: another footing or intersect a filled area which has not been compacted to at Icast 95 percent of ASTM:D 1557. In addition, a 1.5H:1V line extending do��n from a»y footing must not daylight because sloughing or raveling may eventually undern:ine the footing. Thus, foocings should not be placed ncar the edge of steps or cuts in the hearing soils. Anticipated settlrment of footings founded as described abo��e should be on the order of 1 inch. Ho�cver, disturbed suil not removed from footing exca��ations prior to footing placement cuuld result in increased sctdements. All footing areas should be inspected by AESI priur to placing concretc to �erify that the design hearing capacity of the soils has been attained and that construction conforn�s �� ith the recommendations contained in this report. Such inspections may bc rcyuircd b} thc governing municipality. Perimeter footing drains should be pru� i�1eJ �s discussed under the s�ction on Urninnge ConsiAerations. 11 �� s—:�y� ASSOGATED EARTH SCIENCES, I,NC. 1:�'Ir. l.l.�.�y�1r /r�yrni.' dr)�l:l�V. u:n �2��