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Proposed Senior Living Facility—Mounds View, Minnesota Kilo Project 25-2066—December 30,2025 Page 8 of 9 slopes, including outside the bounds of this project. Without erosion control measures, surficial runoff can range from sheet flow to rills, gullies, and gulches, creating channelized flow for larger erosion events over time. Velocity dissipation of stormwater runoff becomes important as flow rates increase from development. Prior to development, many surfaces absorb portions of precipitation through infiltration and have shallower slopes, reducing runoff velocity. As sites are developed, new impervious surfaces are introduced that do not infiltrate precipitation and also reduce the time to peak runoff flows. As a result, higher total runoff volumes and faster flow rates generate higher erosion potential of the subgrade downstream of developed areas. To mitigate this risk, velocity control measures such as silt fences, settling ponds, berms, rip-rap outlets, and other controls can be utilized to slow the flow of runoff leaving developed areas and reduce the erosion caused by such runoff. The intent of velocity dissipation is to reduce peak flow velocities and reduce the erosion potential of a given runoff volume. In addition to velocity dissipation, surficial armoring can be used in high-flow or high-velocity areas to reduce the erosion of a soil subgrade. Surficial armoring is utilizing surface features to "cover"the soils from being eroded, and can consist of new or increased vegetation density, erosion control blankets, turf mats, and other surface cover features. Another alternative is using V-shaped concrete or rip-rap channels at planned stormwater outlets or along existing slopes to create channelized flow and minimize the surficial sheet flows. In order to utilize these armored channels, civil planning, including stormwater flow rates, collection systems, and dissipation systems have to be evaluated to locate and size the channel structures. Providing site-specific, design-level erosion control details was beyond the authorized scope of Kilo's services. The recommendations noted above are not intended to be an exhaustive list, and the specific site conditions and erosion potential should be evaluated by the site civil engineer for the project. REPORT LIMITATIONS The recommendations submitted are based on the project information provided by the client, the subsurface information acquired during the field exploration, and Kilo's engineering experience with similar projects. If project details were to change, including the type of construction or location of features, Kilo should be contacted to verify the validity of these recommendations. If changes do not occur without Kilo having the opportunity to review the changes and revise their recommendations accordingly, Kilo accepts no responsibility for the impact of changes on the project. The geotechnical engineer has endeavored to adhere to generally accepted professional geotechnical engineering practices in the local area with the findings, recommendations, specifications, or professional advice contained in this report. No other warranties are implied or expressed. This report is based on the recommendations contained herein being incorporated into the project plans and specifications, and that adequate construction quality control measures are utilized. This report may be used only by the client, their design team, and only for the purposes stated, within three years from its issuance. Land use, site conditions (both on site and off site) or other factors may change over time, and additional work may be required with the passage of time. Any party other than