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Kraus-Anderson Realty Company Project BL-11-01014 March 18, 2011 Page 10 are generally acceptable for use as fill and backfill at this site. Based on the laboratory moisture content tests, we anticipate that drying of the clayey soils will likely be necessary to achieve the recommended compaction.The contractor should note that moisture conditioning of clayey soils could be labor intensive and require significant amounts of space and time. If site grading and construction is anticipated during cold weather, all snow and ice should be removed from cut and fill areas prior to additional grading. No fill should be placed on frozen subgrades. No frozen soils should be used as fill. D.2.d. Areas of Deep Fill Following deep soil correction excavations in the area of the east end of the eastern wing of the building (Boring ST-104), a relatively substantial (approximately 19 feet)depth of fill may be necessary to reach finish floor elevation. If all of the replacement fill is clayey,thick layers of clay fill tend to consolidate under their own weight.To reduce the effects of this consolidation,the soil compaction levels should be increased along with implementing a time delay to allow the consolidation to occur. It may be necessary to monitor this consolidation using settlement plates to document the rate of consolidation. Based on the depth of backfill necessary in this area of the building, and the composition of anticipated fill soils(i.e., clays),we anticipate that construction delays of 3 to 6 months could be necessary between the time design grades are achieved and when foundation construction can proceed. Settlement plates should be placed in this area prior to fill placement and surveyed every week for the first month and every two weeks until the rate of consolidation has slowed to the point where construction can proceed. If the anticipated construction delay is not acceptable to the project's timeline,then clean sand can be imported and used as a portion,or all,of the deep fill needed to reach design slab elevations instead of on site clay soils.The sand should contain less than 50 percent passing the Number 40 sieve and less than 10 percent passing the Number 200 sieve. This sand should be placed up to at least an elevation where no more than 10 feet of additional clay fill will be needed to reach slab elevation. The sand fill should be placed at least up to elevation 958 or higher. D.3. Spread Footings D.3.a. Allowable Bearing Pressure We recommend that foundations for the proposed building bear upon stiff, or better, native soils and/or new engineered fill material. We recommend that foundations bearing upon these materials be designed BRAUN INTERTEC