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GeoTest Services, Inc. <br />4320 Thomson Avenue, Everett, WA <br />A� <br />March 17, 2022 <br />Project No. 22-0285 <br />by meltwater from the front of the advancing glacier. Stratigraphically, the Till lies over the <br />Advance Outwash. Our on -site explorations indicate that the encountered subsurface soil <br />conditions are in accordance with the Advance Outwash. Basedonour site observations and <br />mapped geologic information, GeoTest expects that Till would be encountered further upslope. <br />Groundwater <br />No groundwater seepage was encountered in the test pits at the time of our investigation on <br />February 2019. The groundwater conditions reported on the exploration logs are for the specific <br />locations and dates indicated, and therefore may not be indicative of other locations and/or <br />times. Groundwater levels and/or seepage rates are not static and it is anticipated that <br />groundwater conditions will vary depending on local subsurface conditions, season, <br />precipitation, changes in land use, and other factors. <br />GEOLOGIC HAZARDS <br />GeoTest previously prepared a Geohazard Evaluation Report for the subject property dated April <br />12, 2019. Please refer to this report for more information regarding geologic hazards for this <br />project and a discussion of mitigations for geologic hazards. <br />CONCLUSIONS AND RECOMMENDATIONS <br />Based on the evaluation of the data collected during this investigation, it is our opinion that the <br />subsurface conditions at the site are suitable for the proposed development, provided the <br />recommendations contained herein are incorporated into the project design. <br />Subsurface explorations in this study generally exposed native, medium -dense, silty sand <br />(weathered Advance Outwash) within approximately 12 inches of existing grade. These soils <br />became unweathered and dense to very dense with depth. GeoTest recommends that any topsoil <br />and loose surficial soils (if present) be removed from the proposed house footprint down to the <br />desired footing grade. The exposed subgrade should be observed by qualified geotechnical <br />personnel to confirm firm and unyielding conditions. Proposed buildings and retaining walls can <br />then be constructed with conventional continuous or individual spread foundations bearing <br />directly on the native Advance Outwash soils. Further recommendations regarding footing <br />subgrade preparation can be found in the Site Preparation and Earthwork section of this report. <br />As discussed in the Project Description section of this report, GeoTest understands that a new <br />soldier pile wall with shotcrete facing will be constructed at the southwest portion of the building <br />excavation. We have provided retaining wall and shoring parameters in a subsequent section of <br />this report for the design of the proposed wall structure. GeoTest understands that the shoring <br />wall will be designed by others. <br />3 <br />