1321 COLBY AVE 1988 PARKING GARAGE AND MEDICAL OFFICE BUILDING Geotech Report 2018-01-02 MF Import

Everett General Hospital & Medical Center W-5557 29 March 1988 Page 6 excavations be observed by a representative of RZA prior to concrete placement to confirm that the condition of the bearing soils are consistent with those assumed in design. Assuming the foundation elements are founded in the recommended bearing soils, we estimate that total settlements should be less than 1 inch with differential settlements of less than 3/4 inch. The majority of settlement would be elastic in nature and should occur during initial loading of the foundation. However, if any disturbed or soft soils are left within the footing areas prior to concrete placement, settlements may be increased. • 4.3 Structural Fill All fill placed within the building area and beneath sidewalk or paved surfaces should be placed as compacted structural fill . Structural fill should be placed after removal of any existing loosened or disturbed soils and after the stripped surface has been prerolled and compacted as recommended in the Site Preparation section of this report. Structural fill should be placed in lifts not exceeding 8 inches in thickness and thoroughly compacted to at least 90 percent of the modified Proctor maximum dry density, at moisture contents within 2 percent of optimum moisture, as described by ASTM:D 1557 test procedure. We recommend that a representative from RZA be present during the placement of structural fill to monitor filling and perform field density tests. In this way, the adequacy of the site fills can be evaluated as grading progresses. The suitability of excavated site soils for compacted structural fill will depend on the gradation and moisture content of the soil when it is placed. Soils containing more than about 5 percent fines by weight (that portion passing the U.S. No. 200 mesh sieve) cannot be consistently compacted to a dense, non-yielding condition at the recommended compaction level when the water content is greater than optimum. Optimum moisture content is that moisture which results in the greatest compacted dry density with the specified compactive effort. J