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Phase II Environmental Site Assessment 2534 Kenzie Terrace WSB Project No. R-020198-000 Page 5 2. Investigation A total of 8 environmental borings (B-1 through B-4 and V-1 through V-4) were advanced at the Site on April 22, 2022, to investigate potential impacts to soil, groundwater, and soil vapor. The environmental borings were completed by Bergerson-Caswell, Inc. of Maple Plain, Minnesota using a truck-mounted push probe drill rig. The boring locations are depicted on Figure 2. 2.1 Soil Sampling Continuous soil sampling was conducted at each boring using a four-foot long rod with a new acetate liner for each sample. The soil borings were advanced to depths that ranged from 24 to 28 feet below grade. Soil profiles were assessed at two-foot intervals and labeled accordingly. Each sample was visually examined for evidence of contamination, field classified, and screened for organic vapors using a PID equipped with a 10.6 eV lamp. Soil boring logs are included as Appendix B. Two soil samples were collected from each of the four soil borings during the investigation and submitted to Eurofins TestAmerica Laboratory of Cedar Falls, Iowa (Eurofins) for analytical testing. In general, soil samples were submitted for laboratory analysis in compliance with the MPCA guidance document 4-01 Soil and Groundwater Assessments Performed During Site Investigations and/or field observations. Following completion of sampling and screening activities, the borings were sealed with bentonite grout in accordance with MDH requirements. 2.2 Groundwater Sampling A total of two groundwater samples were collected and submitted to Eurofins for analytical testing. Groundwater samples were collected by installing a size 10 slotted polyvinyl chloride (PVC) screen (temporary well screen) into the boring, then inserting a section of new polyethylene tubing into the screened well interval. A check valve was used to draw the sample. Groundwater samples collected for RCRA Metals analysis were field filtered prior to laboratory analysis. Unique identification numbers were assigned to groundwater samples using the boring number and the designation of “GW” for groundwater. Water level measurements and screen depths are included in the soil boring logs in Appendix B. 2.3 Soil Vapor Sampling A total of four soil vapor samples were collected from a depth of 4 feet below grade and submitted to Eurofins for analytical testing. Each sample was collected using a one-liter summa canister equipped with a regulator calibrated to collect the sample with an approximate five- minute draw (i.e., a flow rate of 200 milliliters (mL) per minute).