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DRAFT during construction of the project. The field-surfacing materials and fill are underlain by relatively dense gravel and cobbles, which in turn are underlain by relatively dense/stiff sand, gravel, silt, and clay soils derived from the weathering and decomposition of volcanic mudstone and sedimentary rock. Groundwater levels at the site were measured at depths ranging from about 6.5 feet to 7.5 feet between June 3 and August 13, 2021, and we anticipate higher groundwater levels are likely to occur during the wet winter and spring months. As previously discussed, we understand design flood elevations are above the ground surface over much of the site. In our opinion, the primary geotechnical considerations associated with the project include the presence of fill and possible fill soils and relatively high seasonal groundwater levels at the site. Although not encountered during this investigation, the presence of wood and other debris in the fill and possible fill soils at nearby sites presents a risk of encountering unsuitable materials during construction of the project. Our experience with nearby projects indicates groundwater seepage into temporary excavations extending below the groundwater level can be a significant consideration for construction, particularly where zones of more permeable material are present. The results of our investigation indicate the new structures can be supported by shallow foundations as planned, provided the allowable bearing pressures and estimated settlements provided in this report are considered acceptable. In our opinion, the fill soils at the site are generally not suitable for foundation support but may be suitable for support of field surfaces, hardscaping, and building floor slabs, assuming they are relatively free of organics and debris. In this regard, it should be understood that the extents and condition of the existing fill soils are not well known and may not become apparent until construction proceeds. The following sections of this report provide our preliminary conclusions and recommendations for design and construction of the facility and will be reviewed during final design. 5.2 Site Preparation and Earthwork 5.2.1 Site Stripping and Subgrade Preparation The ground surface within the limits of all new building areas, walkways and hardscaping, and areas to receive structural fill should be stripped of existing vegetation, surface organics, soft or loose surface soils, and any unsuitable fill materials. If encountered, any remnants of previous site improvements including existing pavements, foundations and floor slabs, walls, underground utilities, tanks, or other structures, etc., should be removed from within the limits of the proposed improvements and the resulting excavations backfilled with structural fill. In our opinion, all debris from demolition activities should be removed from the site. Organic strippings should be disposed of off site or stockpiled on site for later use in landscaped areas. GRI #6497-A - 2.MO Indoor Football Practice Facility Page 7 August 26, 2021