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May 6, 2015 Page 6 of 1 1 Excavated organic material, uncontrolled fill, wet unstable soil or other soil contaminated with topsoil, vegetation, etc., should be disposed of offsite, or in landscaping areas, where the bearing of weight will not be required. There appears to be some opportunity fo salvage mineral site soil for re-use as controlled fill as some of it, from the southeasfierly area, will be sandy, although with a considerable fines confenf and a high sfandard maximum density. But, the volume will likely be minimal. Other excavated soil will be suitable (organic, over moist or saturated, etc.). Some material for controlled fill placement will have to be imported. Refer to subsequent sections for more detailed and specific recommendations for site correction recommendations for each structural component. 3. Foundations: For purposes of proposed construction, foundations and fill to support foundations must rest upon and over mineral (non-organic) soils of adequate bearing value. As indicated earlier, a bearing capacity of 3000 pounds per square foot (psf) has been targeted oon a preliminary basis. This analysis of soil for foundation purposes is based upon the locations, designs configuration and likely grades indicated above. If there is any significant deviation from any assumptions indicated herein, then these recommendations may have to be reconsidered. If the site is prepared as outlines in #2 above, removing unsuitable soil, performing further excavations as necessary, controlling any water that may enter the excavation and placing controlled fill as necessary, then perimeter footings for the northwest building may be generally designed allowing 3000 psf foundation bearing capacity. This values is recommended on fhe basis of the facfi that foofings will rest upon either naturally occurring mineral soil wifh high penefration values or upon well compacted fill, and wifh any detected softer zones wifihin "one footing width" of footings removed (see above discussion regarding the vicinity of Borings 4& 5). For the southeast building a slightly higher value of 3500 psf may be used due to greater confidence in soils here, especially in that none of the thin zones of wet softer soil were found. Interior pad footings, owing to their square configuration and larger size, and with a minimum of 1'/z feet of confinement, may be designed allowing 3500 psf foundation bearing capacity. Interior strip footings 2 feet wide or greater, again with a minimum of 1'/z foot of confinement, may be designed allowing 2500 psf foundation bearing capacity. These interior bearing capacities could be increased by increasing confinement (i.e. lowering footings), buf only after consulfiation with fhe soils engineer. All of the allowable bearing capacities recommendation take infio account shear failure potential near footing levels and fihe nature of deeper soil regarding settlement potenfiial. Fill, as required, should be placed, compacted, and tested as per the "Fill Placement" (#5) section following. Note that a compaction level of 98% of Standard Maximum Density is recommended. This applies to interior confining soils as well. The above should provide a factor of safety against foundation failure of approximately 3. Over-all and differential settlements should be less than '/s" and '/a", respectively. If footing conditions change from what has been assumed herein, further study and analysis would be necessary. If the site is graded to different levels than assumed above, if fhe fype of building proposed changes or if soils of a significanfily different nature are discovered during excavafions, the Soils Engineer should be contacted for re-analysis and possibly revised recommendations. It is not recommended to place footings upon or over organic soil or any unsuitable soil or to deviate from recommendations contained herein as shear failure of footings or excessive differential settlement of the structure could result. 4. Slabs: Slabs and fill to support slabs should also rest upon and over mineral soil of adequate density fo resisf settlement. Based upon boring evidence, base mineral soils on the site, with