4927 23RD AVE W 2016-01-01 MF Import

DAVID L. NELSON AND ASSOCIATES, INC. Consulting Enginecring Geoiogy September 19, 1989 Project No. 12489 Page 6 Adequate drainage should be provided around the structure area. We si:ggest the use of foundation and roof drain systems, independently directed into the main storm and site drainage system, away from the slope area. Site grading should be performed to direct all surface watars away from the structure and slope area. All work performed within the setback, including excavations or ' landscaping should be performed with adequate drainage, where all surface � waters are directed into a controlled system and properly daylighted away from � the slope. ( Site drainage may require an outfall pipe systr.m which discharges down over the steep slope area to the creek area below, if drainage cannot be directed � to the drainage control system within the street. If this is required, we suggest the system be a tight-line, and utilize a non-jointed, non-ultraviolet � sensitive pipe, placed directly upon the slope surface, and dischar3e �nto an erosion protected outfall located at the toe of the steep slope. The pipe � could be anchored to the slope, but disturbance to the slope surface should be avoided. , Any exposed soils areas within the top-of-slope or slope areas shculd be protected from erosion and weathering. We suggest the use of jute netting, � hydro-seeding or adequate vegetation planting f�r erosi�n control . � Additional Notes Inspection of the earthwork phase of development should be performed. This 7 should include excavations, foundation placement and drainage. i � � Although we do expect site soil types, conditions and distributions to reflect our findings, some variations could occur. Should conditions other than those discussed herein be encountered, the geotechnical consultant should be � notified for review and comment. Additional or alternative recommendations may be required. � 1