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Bolton & Menk, Inc. Proposal QTB172950 February 17, 2023 Page 4 The addendum report will only address recommendations for the additional work on James Avenue. The recommendations in our previous geotechnical evaluation will not change unless stated in the addendum. We will only submit an electronic copy of our report to you unless you request otherwise. At your request, we can also send the report to additional project team members. Environmental Scope of Services Sediment Sampling Our scope is generally based on the Minnesota Pollution Control Agency's current best management practice (MPCA BMP) document (MPCA, 2017). The sampling is proposed to be completed in foot -accessible locations at each of the ponds, either through the ice or wading into the pond at sufficiently shallow locations. Note that if ice conditions are not thick enough (including if ice has not fully receded from the pond in warmer conditions) to conduct the work safely, the work may need to be postponed until pond conditions allow the safe completion of the work. Additional costs may be incurred if more than one mobilization is required due to unsafe conditions. Per your request, and in accordance with MPCA BMPs, we will collect two analytical samples from each pond area provided. The sample will be collected by driving a push probe sampler into the underlying sediment using hand -driven probe sampling equipment. The sample will be comprised of composites from the 0- to 5-foot interval (or shorter interval that is appropriate based on the sediment thickness) from up to three sampling probe locations. For example, for a pond requiring two analytical samples, up to six probes would be advanced, with sediments from three probes composited to make up the first sample, and the remaining three probes comprising the second sample. This method allows for a more representative sample of the sediments that will be dredged from those areas of the pond. For each probe advanced, soil sample textures will be evaluated by visual methods as the samples are collected and noted in the field notes. Drilling tools will be cleaned prior to and between sampling runs by washing the equipment with a brush and water containing trisodium phosphate and rinsing the equipment with water. Where hand -driven probe samplers are used, a clean liner will be used for sample collection for each sample. The samples will be transferred to clean laboratory -supplied containers, preserved in accordance with Braun Intertec Standard Operating Procedures (SOPS) and transported to the Pace Analytical Services laboratory for analysis. Chain of Custody will be initiated at the time of sampling and maintained throughout the process. Each of the sediment samples will be analyzed by the Pace Analytical Services laboratory for the following parameters: BRAVN INTERTEC