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Proposed Senior Living Facility—Mounds View, Minnesota Kilo Project 25-2066—December 30,2025 Page 5 of 9 In general,prior to placement of new engineered fill soils to modify site grades,the existing soils containing organics and the vegetative root mat should be removed from within and 10 feet beyond the proposed building footprint and pavement areas. Roots larger than one inch in diameter should be removed from the subgrade. Areas with visible debris larger than three inches in diameter such as the bricks encountered in the northern portion of the site should be removed. Then, the upper twelve inches of the existing subgrade should be compacted in place. Granular subgrades should be compacted to a minimum relative compaction of 95% using a smooth-drum vibratory roller with a minimum weight of ten tons. Then, the placement of new engineered fill to achieve design site grades can be placed as described below. Based on an anticipated first-level finished floor elevation of 914± feet MSL, nominal amounts of newly placed fill are anticipated in the building area. Newly placed engineered fill required to establish site grades should consist of mineral soils and should be free of organics, frozen soils, ice, debris in excess of three inches, and other deleterious materials. The existing onsite surficial organic soils are not suitable for this purpose due to the presence of organics. Predominantly silt soils are not recommended for use as engineered fill due to concerns with moisture control and material workability. Due to the underlying sand soils, predominantly clay soils are not recommended for mass grading fill due to the risk of ponding water in the fill above the higher permeability sand with silt soils below. Imported fill should consist of granular soils with a maximum of 12% of the material passing the #200 sieve. A qualified special inspections firm or accredited soil engineering laboratory should test the proposed import soils for gradation or plasticity characteristics as appropriate prior to import. Approved soil imports should be tested for optimum moisture content and maximum laboratory dry density in accordance with the Standard Proctor,ASTM D698. Depending on the proposed use of the newly placed engineered fill, the soils should be compacted to the relative densities noted in the table below. Newly placed engineered fill should be placed in thin lifts, moisture conditioned, and adequately compacted prior to new fill placement or final surface cover. The fill soils should be within two percentage points of the optimum moisture content as determined by ASTM D698, Standard Proctor. The fill soils should be placed in horizontal lifts, not parallel to existing slopes. The fill soils should be placed in loose lifts no thicker than 12 inches if full-size compaction equipment with a weight of ten tons or more is utilized. Thinner lifts on the order of 6 inches should be used for lighter weight equipment. Testing of the compacted fills should be completed either with additional DCP testing or with nuclear moisture-density testing and comparison to laboratory maximum densities for quality control by a qualified special inspections agency. The foundations for the proposed Senior Living Facility are anticipated to generally consist of interior column foundations and exterior wall loads. Foundations should bear a minimum of 42 inches below the lowest exterior grades in permanently heated structures such as the proposed residence. Foundations for unheated structures, such as infrequently inhabited cabins or outbuildings, should bear a minimum of 60 inches below the lowest exterior grades. The bearing capacity of the foundations should be assumed to be a code-minimum allowable bearing pressure of 1,500 pounds per square foot unless additional testing is completed at the time of construction. Given the proposed construction,the foundation size is likely to be limited by the recommended minimum foundation size of 30 inches for square column foundations and 18 inches for continuous wall foundations rather than the allowable soil bearing pressure. To achieve the noted bearing pressure of 1,500 pounds per square foot, moisture conditioning and compaction of the soil subgrade will be required as noted in this report prior to and during new engineered fill placement.