5202 HILLTOP RD 2016-01-01 MF Import

DAVID L. NELSON AND ASSOCIATES, INC. Consulling Engineering Geology February 18, 1986 Project No. 1886 _ Page three _ footings, placed within the natural soils as they incline. The excavations to achieve the natural soils elevation may reach greater than 10'-15', so _ that shoring of the excavation may be necessary for worker safety, and to maintain an open excavation. _ Alternately, placement of the foundattons could occur within the artificial fill body, but future settlement and repair of damage to the foundations could occur with time. One method understood to be desired consists of — placement of a deep pier-type footing, founded within the Pill soils several feet below existing grade. A grade beam is then intended to be constructed — betwe�n the pier-footing areas within the deeper portions of the fill body. Use of this type system should utilize maximum soil pressures of 1000 psf. � Settlement of these foundations may occur with time, and remedial repair or „ reconstruction may be required due to distress. _ Another method which is considered marginally safe consists of placement of continuous footings near the existing grade elevation, at least 18" below grade. _ These would be constructed similarly to the existing foundations around the building area, and utilize maximum allowable soil pressures of 1000 psf. Again, post construction settlements within the underlying artificial fill could occur, causing some distress to the foundations. Remedial repair to reconstruction may be required in the future. Buttressing of the existing fill slope could aid in reducing potential future -- movement and/or sl•iding of the fill body. The buttress could consist of soil � placed at the toe-of-slope, worked in by track equipment, and achieve a mean - slope angle of 2H:1V to 3H:1V. Protection of the slope toe soils should be - perforttied, so that erosion downslope and/or downstream does not occur. �,,n:^,� _ The fill slope shows may signs of instability along the out-board sides. The __ signs observed consisted of tension cracking, downdropping, some rilling and � toe erosion. The slope area, regardless of further filling, should be re- vegetated, hydro-seeded, jute netted, or otherwise protected from further �' erosion to maintain as much residual stability as possible. Otherwise, the `� fill slope should be removed and replaced with suitable granular soils.