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

I JJMD Buildings Bobs Burger&Brew JN 09266 INovember 18, 2009 Page 3 IGroundwater No groundwater seepage was observed in the test pits, which were excavated following the I onset of fall rains, but before the typically heavy rains of winter and spring. As discussed above, shallow seepage was observed entering around the storm manhole. This indicates that shallow groundwater may be encountered perched on top of the glacial till soils and/or found within utility trenches. This is most likely to occur following extended wet weather. It I is common to encounter subsurface water perched above and within the relatively impervious glacial till soils, particularly following extended wet weather. • CONCLUSIONS AND RECOMMENDATIONS IGENERAL THIS SECTION CONTAINS A SUMMARY OF OUR STUDY AND FINDINGS FOR THE PURPOSES OF A . ' GENERAL OVERVIEW ONLY. MORE SPECIFIC RECOMMENDATIONS AND CONCLUSIONS ARE I CONTAINED IN THE REMAINDER OF THIS REPORT. ANY PARTY RELYING ON THIS REPORT SHOULD READ THE ENTIRE DOCUMENT. I The test pits excavated for this study encountered dense to very dense glacial till at a relatively shallow depth. Based on the absence of the typical weathered layer usually found over glacial till soils, it is apparent that much of the lot was cut down during past grading for the site development. I The undisturbed glacial till soils are suitable to support the proposed structure using conventional foundations. The glacial till can be easily disturbed by foot traffic during the placement of forms and reinforcing steel. As a result, we recommend that the footing subgrades be protected with 4 to 6 inches of clean crushed rock after the subgrade soils have been scraped clean of any loose or Idisturbed soil. Given the potential for shallow perched water on top of the glacial till, we recommend that the floor I slab be situated above the existing grade and be underlain by at least 6 inches of clean crush rock as a capillary break/drainage layer. I A retaining wall is planned along the north side of the project sothat the-existing sloped landscape area can be excavated to create more parking. Considering the proximity of this wall to the northern property line and the paved driveway on the adjoining northern property, it appears that a reinforced retaining wall will be necessary. Less aggressive retaining structures, such as rockeries, I or modular block or ecology block walls are not suitable to support surcharges from vehicle traffic. Depending on the location of the retaining wall, it may be necessary to temporarily excavate onto the adjoining property to allow construction of the wall. The wall's footing and drainage system I would need to be located within the boundaries of the site. Also, provisions should be included for any surface drainage off that pavement. I The glacial till soils had a relatively high moisture content at the time of our field explorations. These fine-grained soils are moisture sensitive and cannot be properly compacted when their moisture content is too high. Reuse of these soils as structural fill beneath the footings should not I be attempted. The excavated soils could be reused as structural fill under slab and pavement areas only if earthwork occurs during dry weather, when the overly-moist soils can be dried prior to compaction. This would slow the earthwork process, and would not be successful during wet weather. IGEOTECH CONSULTANTS,INC.