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Mr. David Swearingen December 10, 2019 Page 3 Task 3 – Work Plan Based on the results of the Desktop Environmental Review and the Phase I ESA, WSB will prepare a written Work Plan outlining the borings, locations, sampling depths, and sample parameters to define the extent and magnitude of potential subsurface contamination that may be encountered during reconstruction along the Corridor. The Work Plan will include costs for sample collection and chemical analysis of soil, groundwater, and soil vapor samples. The Work Plan will also contain estimated sample collection/analysis costs, as well as, a boring location and sampling rational. Lastly, the Work Plan will be provided to the City for review and approval. Task 4 – Field Investigation Utilizing the approved Work Plan, WSB will perform a Field Investigation along the Corridor. The Field Investigation will include the advancement of geoprobe borings along the Corridor to determine 1.) whether contamination impacts to soil, groundwater, or soil vapor exist within the project reconstruction limits and 2.) provide data to support the proper management of excavated material that may be generated during construction. The following activities will be completed as part of the Field Investigation: ● Subcontract Bergerson Caswell, Inc. of Maple Plain, Minnesota to complete the environmental drilling and Eurofins/TestAmerica of Minneapolis, Minnesota to complete laboratory analyses. ● Stake boring locations (14 total). ● Locate public/private utilities using Gopher State One Call (GSOC) and a private locator (if needed). ● As necessary, provide traffic control for lane/shoulder closures in accordance with MnDOT’s Temporary Traffic Control Layouts Field Manual, January 2018, as amended. ● Advance 14 geoprobe borings along the Corridor to 15 feet below grade, ● Screen soils using a photoionization detector (PID) with a 10.6 eV lamp. ● Record general soil classifications/observations in a field log, including visual, olfactory, and other indications of contamination. ● Record general groundwater information including depths, odors, colors, staining, and other general field observations. ● Field record boring locations using GPS (Global Positioning System) technology. ● Seal borings per Minnesota Department of Health regulations. ● Collect samples for standard 10-day laboratory analysis as described below. o Soil – 28 samples for Diesel Range Organics (DRO), Gasoline Range Organics (GRO), benzene, toluene, ethylbenzene, xylenes (BTEX), and Lead o Groundwater – 2 samples for DRO, GRO, BTEX, and Lead o Soil Vapor – 2 samples for Volatile organic Compounds (VOCs) using method TO-15 o Note: PCB soil samples will be collected at each sample location and placed on hold. If DRO is detected, then the PCB samples may be analyzed at select locations with approval from the City/County. Task 5 – Project Report WSB will provide a Project Report summarizing the results of the Field Investigation. The Project Report will include figures, tables, boring logs, laboratory reports, conclusions, and recommendations. The conclusions/recommendations will include actions to address contamination anticipated to be encountered along the Corridor during reconstruction. WSB will