Report/excavation observation/compaction testing

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- AET Job No. 20-06374 - Page 5 of 6 Since portions of the mass excavation terminated below foundation grades, 1:1 oversizing of the excavation bottoms and subsequent fill system was recommended. Our judgments of the excavation oversizing were based on the GPS positionina a�d elevation information provided for us in the field by the excavating subcontractor. Based on the information provided, it appeared that sufficiemt 1:1 lateral oversizing was provided for the majoriry of the mass excavation. Only the footprint of the addition was corrected adjacent to the existing building. The soils under the northeast corner of the existing building consisted of darker colored existing fill or topsoil,therefore,the excavation for the new interior footings and interior column pads adjacent to this area could not be provided with the recommended 1:1 oversizing. This was discussed with Marv Showers of James Steele Construction and Loren Morschen of Architects Rego + Youngquist Inc., on September 6, 2006. It was decided that addition excavation or lowering of the footings would not be needed. FILL COMPACTION TESTING During the period from August 28, 2006 to September 7, 2006, we conducted 18 density tests in fill placed in the building. The density tests were conducted on a will-call basis. The field densiry tests were compared to the laboratory Standard Proctor maximum drY density(ASTM:D698)to arrive at a percent compaction level for each test. The test results, which are attached, indicated the specified compaction level was ultimately met or exceeded at the locations and elevations tested. The result of test#10 did not meet the specified compaction level with the initial compactive effort. We recommended the soils in this area be recompacted. A retest (test #13R) was taken after this corrective effort. The result of this retest achieved the specified compaction level at the location and elevation tested.