11310 EVERGREEN WAY 2018-01-01 MF Import

Mr. Bruce Vanderwall - . . April 16, 2008 GROUNDWATER During our field work, we did not obseroe arry signiflcant seepage in the borings. • Some damp soils and light seepage was noted near the base of Boring &3 within the glacial tilI layer. We anticipate that the seepage exists within a small sand layer in the till or on top of the impeMous till soil. Wintertime seepage can become perched on the low permeabiHry sotls under the site. Some fluctuations in the seepage wa�r levels at � the site can also be expected following periods of heavy precipitaaon and in the winter. DISCUSSION AND RECOMMENDATIONS _ � General From a geotechniql standpoint, the site is suitable for the proposed construttion. The � new building and fadlities can be supported on conventional spread footlngs and floor slabs bearing on competent native soils below the fills or on compacted stnutural fllls placed after the old fills have been removed from under foodng areas. If required, spread footings can also be supported on quarry rock fill placed and compacted over the competent native soils. Concrete slabs can be similarly supported on the recompacted subgrade present at the site or on new compacted structurel fills. Site Preoaration and Gradina To prepare the site for construction, the old building, its slabs and foundations, as well as other deleterious materials should be removed from below new footing and slab-on- grede areas. Soils containing organic material will not be suitable for use as strudural fill, but may be used in non-structural areas or for landscaping purposes. Foundation subgrade preparadon is discussed in the Foundation section of this report. The on-site native soils found around the north and east sides of the site generally appear suitable for use as structural fill during dry periods of the year. Some of the old fills around the west and south sides of the old building contain some organic materials and may not be suitable for reuse as structutal fill. Also, site preparation may reveal other localized areas of debris laden fills below the subgrade. These materials should be overexcavated to their full depth in foundation and strur_tural areas. All subgrade areas should be compacted prior to placement of new fills or slab subgredes. Any soRened or loosened areas should be overexcavated and replaced with drier materials to achieve a stable, non-yielding surface. These over excavaUons may include any soft old utility trench areas. The ability to use near surface silty sands and grevels from site excavations as structural fill will depend on their moisture content and the prevailing weather conditions at the time of construction. Project No. 123Y • Page No 5/ /�� �_