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(assumes 12 structures), including rim and invert elevations. Complete storm structure inventories on existing structures identified by city public works staff for replacement (assumes 13 structures), including rim and invert elevations. All other storm structures will not be inventoried. Bolton & Menk will also complete a bathymetric assessment of each of the three identified stormwater pond areas to quantify the sediment to be removed. This process includes an assessment of original as -built and/or design information, verification of normal pool elevations, and quantification of sediment. It is assumed that the bathymetric survey will only require data collection up to and below the water level. If additional data collection from the edge of water to the top of slope is necessary, it can be added to our proposal for an additional cost. The following further describes the scope of work: • Capture Light Detection and Ranging WDAR) surface contours near basins • Using a kayak, we will measure the depth to the top of sediment, then push the blunt -ended grade rod to the hard bottom and measure again. These depths are recorded, along with a GPS waypoint, for digital surface modeling. We will compare the measured hard bottom to the original as -built and/or design information (if available) and present to the city. If these elevations differ significantly, then a verification check may be appropriate. • Our measurement technique also utilizes a depth finder attached to the kayak. Depending on when in the year the bathymetric data is collected, the sonar returns from vegetation can cloud the dataset. Therefore, the sonar data will be collected and further vetted for accuracy as digital surface datasets are compiled. • Using AutoCAD tools, the collected data will be converted and compiled in a digital format. Surface models will be created to simply quantify the total accumulated volume. These models are also provided to the contractor, should they use automated equipment for sediment removal. • For dry, or very shallow (less than 2 feet) ponds, traditional topographic survey methods will be used. • County GIS parcel linework will be used for right-of-way and property lines. Topographic survey and the proposed strom sewer layout for drainage improvements near 4242 Norma Avenue are assumed to be provided by the city. An electronic base map will be created and submitted to the city for review prior to initiating design work based on the field, aerial, and bathymetric surveys. It is assumed that no easement exhibits will be required for the project. Task 4: Geotechnical Evaluation We have partnered with Braun Intertec for geotechnical evaluation services on this project. Braun has extensive experience performing these preliminary materials investigation tasks on other projects. They have worked with the City of Arden Hills on a number of recent projects and are well -versed in the city's expectations. A full scope of services and assumptions from Braun is included at the end of this proposal. The fee for this task includes a 10% overhead cost for Bolton & Menk to coordinate the work. The city utilized Braun to complete the initial Pavement Evaluation Report for the project area. However, since then, the project scope has changed slightly requiring further investigations. Work under this task includes conducting soil borings on the reconstruction area (James Avenue) because only a pavement core was conducted with the initial investigation, providing a pavement section recommendation for the reconstruction area, and conducting pond sediment sampling, testing, and analysis consistent with MPCA standards (Managing Stormwater Sediment Best Management Practice Guidance) at the three identified pond locations to determine the MPCA management level necessary for landfilling of the excavated material generated from dredging the ponds. Braun will then generate an amendment to the initial geotechnical report that will include these additional findings and recommendations for the project scope. Task 5: Public Engagement Effective, consistent public engagement is a key component to the overall success of any project. Bolton & Menk's extensive communications capabilities allow us to provide you with a tailored approach to engagement that is organized, efficient, and proactive. Bolton & Menk will engage the public and provide a forum for valuable project discussion. We will work with city staff to develop a survey or questionnaire that city staff will mail to impacted property owners during the feasibility study process to identify key project issues and concerns from residents and businesses. This information will be summarized and incorporated in the feasibility report. We will conduct an open house style public informational meeting during the design of construction plans to inform residents of the proposed improvements. We will solicit comments and inputs from residents. These comments will be discussed with city staff and incorporated into the project design, as directed. Bolton & Menk will conduct a second public informational meeting prior to the start of construction. This meeting will focus on what to expect during the construction process, schedule, access, and impacts. Of particular note, the open house will discuss the construction staging plan and estimated duration, access considerations during the utility construction, and what residents may see during construction to plant the seeds of what they can anticipate in advance.