1605 SE EVERETT MALL WAY BOBS BURGER AND BREW Geotech Report 2025-07-25

1 JJMD Buildings Bobs Burger&Brew JN 09266 ' November 18, 2009 Page 4 If the elevation of the pavement will be close to the surface of the glacial till, it will be important to provide measures for drainage beneath the pavement. A subsurface interceptor drain would need to be installed along the outer edge of the paved area. This drain would consist of a gravel-filled trench extending 12 to 18 inches into the glacial till, with non-woven filter fabric lining the trench. A perforated PVC pipe would be buried in the bottom of the trench to collect intercepted groundwater. The surface of the glacial till would then need to be sloped toward the perimeter intercept trench. Additionally, the lower 3 to 4 inches of the crushed rock base layer would need to consist of clean crush rock that could transmit water through the perimeter interceptor drain. If the existing storm manhole and pipes are abandoned, they should be removed and the resulting excavations filled with low permeability backfill. This prevents them from being conduits for subsurface water. The erosion control measures needed during the site development will depend heavily on the weather conditions that are encountered. We anticipate that a silt fence will be needed around the downslope sides of any cleared areas. The existing pavements should remain for temporary use wherever possible. Rocked construction access roads should be extended into the site to reduce ' the amount of soil or mud carried off the property by trucks and equipment. Wherever possible, these roads should follow the alignment of planned pavements, and trucks should not be allowed to drive off of the rock-covered areas. Existing catch basins in, and immediately downslope of, the ' planned work areas should be protected with pre-manufactured silt socks. Cut slopes and soil stockpiles should be covered with plastic during wet weather. Following rough grading, it may be necessary to mulch or hydroseed bare areas that will not be immediately covered with landscaping ' or an impervious surface. As with any project, additional erosion control measures may need to be implemented to address conditions encountered during site work. The drainage and/or waterproofing recommendations presented in this report are intended only to prevent active seepage from flowing through concrete walls or slabs. Even in the absence of active seepage into and beneath structures, water vapor can migrate through walls, slabs, and floors from the surrounding soil, and can even be transmitted from slabs and foundation walls due to the ' concrete curing process. Water vapor also results from occupant uses, such as cooking. Excessive water vapor trapped within structures can result in a variety of undesirable conditions, including, but not limited to, moisture problems with flooring systems, excessively moist air within occupied areas, and the growth of molds, fungi, and other biological organisms that may be harmful to the health of the occupants. The designer or architect must consider the potential vapor sources and likely occupant uses, and provide sufficient ventilation, either passive or mechanical, to prevent a build up of excessive water vapor within the planned structure. . Geotech Consultants, Inc. should be allowed to review the final development plans to verify that the recommendations presented in this report are adequately addressed in the design. Such a plan review would be additional work beyond the current scope of work for this study, and it may include revisions to our recommendations . to accommodate site, development, and geotechnical v . We recommendconstraintsthat includingbecomemore this reportevident, in itsduring entiretythere, iniew the proprocessject contract documents. This report should also be provided to any future property owners so they will be aware of our findings and ' recommendations. • ' GEOTECH CONSULTANTS,INC.