4107 OLIVE ST 2018-01-02 MF Import

JAN-22-4E FRI 14__20 ` r • . � h tom+/ DAVID L. NELSON AND ASSOCIATES, INC. + Consulting Engineering Gmlogv October 10, 1990 projeo4 no. 9490 page 6 the site is stable with respect to doep seated elides. The steeper gradients on site could be susceptible to shallow sloughing failures downslope, if grind rater seepage (springs) were to occur in this vicinity. Provisions for maintaining existing slope stability, including drainage control, earthwork (filling and grading) control and structury plaeem At, are Presented herein to reduce potential risk of slope failures. landslida hazard within this area is considered low, particularly if the reeoamndations presented in the previous geotecbnionl evaluation report are followed. Springs/Ormond Water Seepage Areas %%sao two elemannts mentioned in the now ordinance are similar eonuiitiona, which are discussed together in this letter. During our evaluation of the site, we observed the surface areas for springs and seeps, and observed our backhom exploration (test) pits for ground Crater seepage Conditions. We did not encomter any evidence of springs or seeps within the site along the easterly slope. We did observe evidence of seepage along the northerly steep ant slope of Temple Drive, and downslopo of the site to the east. This would indicate that ground crater does occur within the area, but as interflow and perched water within the surficial sandy soils and above the relatively fapereeable glacial till and/or intorglacial silts. Where excavations occur (such as Teeple Drive) and they intersect this perched water, ground water aeepaYi, or springs, may Occur. our discussions and room mmdations in the previous gectechnical report present methods of mitigation of any perched or seeps" waters encountered during construction. Springs are not observed within the easterly sloping portion of the property perhaps due to reduced perched water, or that no excavations occur within this area. The springs noted dowaslope of the site are exported to be the elevations at which the perched water intersects the ground surface. Steep Slopes Associated With The Above Elements The new ordinance states that atenp elopes are those at 25 percent or greater.