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Memo \ U:\227705255\technical To: City Council – City of St. Anthony Village From: Ryan McElrath CC: Khaleef A.H. Warsame Tibyan Community Center Stantec Consulting Services Inc. File: Stantec Project No: 227707229 Previous MPCA Site IDs: BF0002310 and BF0002577 Date: September 18, 2024 Reference: Environmental Conditions Summary – Proposed Tibyan Community Center, 2401 Lowry Avenue NE, St. Anthony, Minnesota (the Site) Stantec Consulting Services Inc. (Stantec) has prepared this Environmental Conditions Summary (Summary) letter to detail the previously completed environmental investigations for the Site and to characterize the current Site conditions as understood based on the data in hand. Stantec has prepared this Summary on behalf of Tibyan Community Center in support of the proposed use of the Site as a community meeting space. The Site Location is depicted in Figure 1. A Site detail map is provided in Figure 2. Previous Environmental Investigation Summary The 1.89-acre Site was initially developed in the 1930s as a tourist camp including a campground office building and several cabins and trailers. By 1940, a grocery store and fuel station were added onto the office building. By 1953, those buildings were demolished, and a slab-on-grade building was constructed on the north-central portion of the Site. By 1966, a building addition was extended from the eastern wall of the slab- on-grade building. During the 1960s and 1970s, a dental office, carpet retailer, and a dry cleaner occupied the Site. In 1979, the Site buildings were again demolished, and the Site was redeveloped with the existing Site building, which was initially occupied by law firms and financial service businesses. Bremer Bank occupied the Site for its financial services business from 2001 until 2022. The Site has remained vacant since Bremer Bank’s departure. In August 2017 and October 2017, a subsurface investigation was conducted at the Site with the advancement of 11 soil borings, three of which were hand-augured beneath the building footprint. In total, 14 soil samples were analyzed for various contaminants, including the eight Resource Conservation and Recovery Act (RCRA) metals; diesel range organics (DRO); polycyclic aromatic hydrocarbons (PAHs); and volatile organic compounds (VOCs). Various compounds were detected in soil samples at concentrations above their respective Minnesota Pollution Control Agency (MPCA) soil leaching values (SLVs) but less than their respective residential soil reference values (SRVs). Six groundwater samples were collected from temporary wells and monitoring wells and analyzed for VOCs. Chlorinated VOCs tetrachloroethylene (PCE), trichloroethylene (TCE), and cis-1,2-dichloroethene (cis-1,2-DCE) as well as the petroleum-related VOC benzene were detected in groundwater samples at concentrations greater than their respective Health Risk Limits (HRL) established by the Minnesota Department of Health (MDH). Three sub-slab soil vapor samples and four exterior soil vapor samples were collected at the Site in August 2017 within the MPCA-defined non-heating season. Soil vapor beneath the parking lot, specifically in areas located north and east of the Site building, was impacted by numerous chlorinated VOCs, including PCE and TCE at concentrations greater than the vapor mitigation action level of thirty-three times (33X) the MPCA’s industrial expedited intrusion screening value (EISV). Sub-slab soil vapor collected from within the northeast corner of the building footprint had TCE at concentrations greater than 33X the MPCA’s industrial ISV. Soil vapor was also impacted by elevated levels of cis-1,2-DCE, however an ISV had not been established for cis- 1,2-DCE at the time. 72