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REVIEWED BLD BLD2021-0873+GEO REPORT+6.22.2021_10.57.13_AM+2262618CONSULTANTS, INC- John McCallum 21630-98 1h Avenue West Edmonds, Washington 98020 via email. Subject: Foundation Evaluation Existing Single -Family Residence 21630 — 98th Avenue West Edmonds, Washington 2401 1 Oth Ave E Seattle, Washington 98102 (425) 747-5618 On December 22, 2020, the undersigned Principal of Geotech Consultants met with you at your residence at 21630 — 98th Avenue West in Edmonds. We observed the conditions of the residence during our visit, more specifically the northem/northwestem portion, and also observed the soil conditions in some test holes that were excavated outside of the residence perimeter in this area. This report provides recommendations and conclusions regarding the foundation of the residence; these are professional opinions based on our recent observations and our experience in the Puget Sound Area. The moderately large residential property is located on the downslope, western side of 98" Avenue West in the eastern portion of Edmonds. The overall property slopes mostly gently downwards to the west. The existing, brick -structure residence is located on the eastern, upslope portion of the property. It has a lower, basement/garage level that daylights to the north and west; the garage entrance is on the eastern end of the northern side of the residence. The slab grade of the basement/garage level is essentially the same as the ground adjacent to its northern and western sides, except that the slab at the very northwestern comer is up to approximately 15 inches above the ground. The main level of the residence overlies the entire basement, except that is just larger than the basement/garage level at the eastern end of its northern side (where the garage entry is located). Cracks in brick walls of the residence are easily visible in the very northwestern corner, and a crack in the concrete foundation also can be seen on its northern side about 5 feet from the northwestern corner. A crack in the interior drywall in the basement also exists in a similar location to the foundation crack. Another very noticeable crack is located on the northern side of the residence's main level of residence above the western end of the garage where the main level extends out over the basement/garage level. We excavated three test holes with hand equipment at/near the northwestern corner of the residence. Two were excavated adjacent to the northern edge of the residence, while the third was located about 6 feet west of the northwestern corner. On the northern edge of the residence, the test holes revealed that the top of the footing foundation exists at approximately 3.5 feet of below the ground surface; this would indicate that the likely depth of the bottom of the footing foundation is at approximately 4.5 feet below the ground surface. Loose soil was revealed overlying dense native soil to a depth of about 5.5 feet at the northwestern comer, but at a depth of about 4.5 feet in a test McCallum December 30, 2020 IMINkI JN 20483 Page 3 The conclusions and recommendations contained in this report are based on site conditions as they existed at the time of our site visit and assume that the soil conditions encountered in the test holes are representative of subsurface conditions on the site. If the subsurface conditions encountered during construction are significantly different from those observed in our explorations, we should be advised at once so that we can review these conditions and reconsider our recommendations where necessary. Unanticipated conditions are commonly encountered on construction sites and cannot be fully anticipated by the explorations. Subsurface conditions can also vary between exploration locations. Such unexpected conditions frequently require making addonal expenditures to attain a properly constructed project. It is recommended that the owner consider providing a contingency fund to accommodate such potential extra costs and risks. This is a standard recommendation for all projects. This report has been prepared for the exclusive use of John McCallum and his representatives for specific application to this project and site. Our conclusions and recommendations are professional opinions derived in accordance with our understanding of current local standards of practice, and within the scope of our services. No warranty is expressed or implied. The scope of our services does not include services related to construction safety precautions, and our recommendations are not intended to direct the contractor's methods, techniques, sequences, or procedures, except as specifically described in our report for consideration in design. Our services also do not include assessing or minimizing the potential for biological hazards, such as mold, bacteria, mildew and fungi in either the existing or proposed site development. Geotech Consultants, Inc. should be retained to provide geotechnical consultation, testing, and observation services during construction. This is to confirm that subsurface conditions ars consistent with those indicated by our exploration, to evaluate whether earthwork and foundation construction actives comply with the general intent of the recommendations presented in this report, and to provide suggestions for design changes in the event subsurface conditions differ from those anticipated prior to the start of construction. However, our work would not include the supervision or direction of the actual work of the contractor and its employees or agents. Also, job and site safety, and dimensional measurements, will be the responsibility of the contractor. During the construction phase, we will provide geotechnical observation and testing services when requested by you or your representatives. Please be aware that we can only document site work we actually observe. It is still the responsibility of your contractor or on -site construction team to verify that our recommendations are being followed, whether we are present at the site or not. We appreciate the opportunity to be of service on this project. Please contact us if you have any questions, or if we can be of further assistance. -410 .1 Z= M Robert Ward, P. E. Principal -,����f is r �L, i2/30/20