2710 VIEWCREST AVE 2016-01-01 MF Import

Thomas Kelly JN 95192 June 7, 1995 Page 3 department states that it may be able to authorize slope buHer width averaging. The butter may be decreased to 12.5 feet, if the buHer being increased in width has similar or better vegetation than the buHer being decreased in width. The city also requires adequate protection for Powder Mill Gulch and a geotechnical angineerin� study that addresses the requirements of the Sensitive Areas Ordinance. As indicated on the test pit logs, the soils at the house site consist of fine- to medium- grained sands. These sands are loose to medium-dense. Sands are highly erodible, but they are not susceptible to deep sliding. If adequate erosion protection is provided and surface water is properly disposed of, it is our opinion that the buffer can be reduced to a minimum of 15 feet from the edge of the steep slope. We do not recommend placing fill on iiie slope, and any disturbed areas should be revegetated with native vegetation. The house may be supported on conventional foundations on the sands underlyin� the topsoil. We recommend wetting and recompacting the sands in footing trenches, !hey are relat�vely loose. Footings should be founded a minimum of 2.5 feet below the e:•.�sting ground surface. Gonve nti4.ng!_Esuad�ti2ns The proposed structure can be supported on conve^tionai continuous and spread footings bearing on undlsturbed, native sand soils, or on structural fill placed above these competent, native soils. See the later sub-section entitled General E�rthwork a��1 StLUS�tuf�LE�lI for recommendations regarding the placement and compaction of structural fill beneath structures. We recommend that contfnuous and individual spread footings have minimum widths of 16 and 24 inches, respectively. They should be bottomed at least 12 inches below the lowest adjacent tinish ground surtace for frost prutection. The local � building codes should be reviewed to determine it different footing widths or embedment j depths aro required. The footing may be designed tor an allowable bearing pressure of ' 2,000 pounds par square foot (ps�. A one-third increase in this design bearing pressure � may be used when consfdering short-term wind or seismic loads. � Lateral loads due to wind or seismic torces may be resisted by friction between ihe founaa- ' tions and the bearing soils, or by passive earth pressure actlng on the vertical, embedded portions of the foundations. For the latter condition, the foundations must be either poured directly against relatively level, undisturbed soil, or surrounded by level structural fill. We recommend using the foilowing �lesign values for the foundation's resistanco to lateral loading: I i 1 GI'A97>CII CONSUL9iAMS,ING � ,