03-28-1994 Council Packet - Laserfiche WebLink

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David Vergeylc March 15, 1994 RESULTS Boring Logs indicating the depths and identifications of the soil strata, penetration resistances and ground water observations are attached. The strata changes were inferred unless observed in the samples. Please note that the depths shown to the various strata arc approximate, the transitions in the field may vary between borings and may not be sharply defined. We found approximately 4 feet of fill in boring 1. This fill was placed over the existing topsoil. The soils below 4 feet were firm sandy clays and dense sands with gravel We found 6 inches of topsoil in boring 2 overlying sandy clays and sands similar to those found in boring 1. We did not 'ncounter fill in boring 2. Both borings ended at 17 feet. We did not encounter groundwater in either boring. RECOMMENDATIONS The fill found in boring 1 is not suitable for footing support. The fill should be removed under a*l footing and slab areas. The sandy clays and dense sands found below 4 1/2 feet in boring 1 and below the topsoil in boring 2 are suitable for footmg support. If fill is required under footings or slabs, the topsoil must be removed prior to fill placement. T^e fill should be non-organic and be placed in 1 foot lifts and compacted with a self-propelled compactor to a minimum of 90% Modified proctor density. The fill should be tested at 2 foot vertical intervals. We recommend retaining the services of a competent soils engmeer to observe the removal of the topsoU and placement of the fill. ,\ny excavations for placeinent of fill that will support the footings should be oversized laterally 1 foot for each 1 foot of fill placed. The proposed struemre should be placed so that there is at least a 1 H to 1 V slope between a point 2 feet outside of the footing and the toe of the slope. The proposed footings should be sized for a maximum allowable soil bearing pressure of 2500 pounds per square foot. This sizing is applicable footings placed on naturally occurring non-organic soils or on compacted fill. The lowest footings will be at ^ elevation of 948 and the base of the slope is approximately 934, a difference of 14 feet. The approximate distance between the struemre and the base of the slope is 30 feet. The existmg slope is approximately 2 horizontal to 1 vertical. The site as currently designed is suitable for placement of the house. LIMITATIONS OF EXPLORATION PROGRAM The observations and recommendations of this report are based on the data obtaiiied from 2 standard penetration borings Soil conditions between borings may differ from our observations. No exploration program can fully disclose all subsurface conditions. The conditions described can only be considered accurate at the locations and elevations sampled.