7815 E GLEN DR 2016-01-01 MF Import

After overexcavation/stripping has been performed to the satisfaction of the geotechnical engineer/engineering geologist, the upper 12 inches of exposed ground should be recompacted ro a minimum of 9Q percent of the modified Proctor maximum density using AST'M:D 1557 as the standard. If the subgrade contains too much moisture, adequate recompaction may be difficult or impossible to obtain and should probably not be attempted. In lieu of � recompaction, the area to receive fill should be blanketed with washed rock or quarry spalls to act as a capillary Ureak between the new fill and the wet subgrade. After recompaction of the exposed ground is tested and approved, or a free-draining rock course is laid, strucnual fill may be placed to attain desired grades. Structural fill is defined as non-organic soil, acceptable to the geotechnical engineer, placed in maximum 8-inch loose lifts, with each lift being compacted to a minimum of 95 percent of the modified Proctor maximum densiry using ASTM:D 1557 as the standard. The top of the compacted fill should extend horizontatly outward a minimum distance of 3 feet beyond the location of the peruneter footings or pavement edge before sloping down at an angle of 2H:1 V. The contractor should note that any proposed fill soils ruust be evaluated by Associated Earth Sciences, Inc. (AESn prior to their use in fills. This would require that we have a sample of the matcrial 48 hours in advance to perform a Procror test and determine its field compaction standazd. Soils in which the amount of fine-grained material (smaller than No. 200 sieve) is greater than approximately 5 percent (measured on the minus No. 4 sieve size) should be considered moisture-sensitive. Use of moisture-sensitive soil in structural fiqs should be limited to favorable dry weather conditions. The on-site lodgement till sediments are suitable for use as structural fill, however, much of this ►r'.aterial was wet at the time of our site visit and L5e specified compaction may not be achievabie without prior moisture conditioning. In addition, construction equipment traversing the site when the soils are wet can cause considerable disturbance. If fill is placed during wet weather or if proper compaction cannot Ue obtained, a select import material consisting of a clean, free-draining gravel and;or. sand should be used. Free-draining fill consists of non-orgar.ic soil with the amount of fine-grained material limited to 5 percent by weight when measured on the minus No. 4 sieve fraction. A representative from our firm should inspect the stripped subgrade and be present during placement of structural fill to observe the work and perform a representative number of in- place density tests. In this way, the adequacy of the earthwork may be evaluated as filling progresses and any problem areas may be conected at that tune. 11.0 FOUNllATIONS Substantial thicknesses of uncontrolled fill and loose, organic topsoil or topsoil fill are present beneath the area of the proposed building. The depth to bearing soils in the exploration pits excavated for our study ranged from approximately 6 co 7 feet and is andcipated to be somewhat deeper than this range along !he west side ef the proposed buiiding. Presented below are tH�o options for foundation suppor[. 10 �,�y. ,