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AET #22-00173- Page 4 of 10 <br /> Water Level Measurements <br /> We encountered groundwater at a depth of about 4'/2 feet below grade at both borings, which <br /> corresponds to approximately elevation 928. The cohesive fill soils on this site are estimated to <br /> have relatively low permeabilities, and an extended period of time, on the order of days or <br /> weeks, would be required for the groundwater to reach equilibrium levels in the borings. Thus, it <br /> is likely that groundwater may be shallower on this site than indicated by the 1eve1 of free water <br /> measured in the borehole during the relatively short period of time (approximately two hours per <br /> boring) in which we drilled. While on the site, we shot the elevation of tl�e ice at the shoreline of <br /> Lake Minnetonka, which abuts the northern portion of the property. The elevation of the ice was <br /> 928.7. This is slightly above the average water ]evel of the lake of 928.44 feet, but below the <br /> ordinary high water (OHW) elevation of 929.4 feet, according to the Minnesota Department of <br /> Natural Resources website. We believe groundwater elevation at the house will closely match <br /> the elevation of Lake Minnetonka due to the proximity of the lake. A discussion of the water <br /> level measurement methods is presented on the attached sheet entitled <br /> "Exploration/Classification Methods." <br /> Groundwater levels usually fluctuate. Fluctuations occur due to varying seasonal and yearly <br /> rainfall and snow melt, as wel] as other factors. <br /> RECOMMENDATIONS <br /> Based on our understanding of the performance of the original construction, existing foundation <br /> depths, and dimensions and loads associated with the planned new construction, it is our <br /> professional opinion that the existing foundation is suitable for support of the new constniction. <br /> It is also our opinion the subsurface soil conditions are suitable for support of typical spread <br /> footing foundations in the area of the new garage addition. As a result of the added loads from <br /> the new structure and fill soils that will be placed to infill the crawlspace area, some settlement <br /> will occur to the existing foundations and new grade supported slab. Oak Hill, Inc. will need to <br /> determine if the anticipated settlement is tolerable. <br />