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Phase I Environmental Site Assessment Old Snelling Avenue & County Road E Improvements WSB Project No. 015447-000 Page 17 8. Findings and Opinions 8.1 Recognized Environmental Conditions The ASTM E1527-13 Standard defines the term recognized environmental condition (REC) as meaning “the presence or likely presence of any hazardous substances or petroleum products in, on, or at a Project Corridor: (1) due to release to the environment; (2) under conditions indicative of a release to the environment; or (3) under conditions that pose a material threat of a future release to the environment.” Based on this assessment, two (2) RECs were identified in connection with the Project Corridor (see Figure 3). The following RECs were identified: REC-1: Contaminated Soils Encountered During Bridge Replacement Contaminated soil was encountered in 2018 during the replacement of Bridge 62J17 located on the southern portion of the Project Corridor. Soil samples collected from three stockpiles generated during construction identified BaP equivalent concentrations above the MPCA SLV and DRO above the MPCA’s criteria for unregulated fill. Based on the analytical results, a total of 486 cubic yards of PAH- and DRO-impacted soil was removed during bridge construction and disposed offsite at a certified landfill. It is possible that contaminated soil remains in this area. The former and/or current presence of PAH- and DRO- impacted soil in the vicinity of Bridge 62J17 is considered a REC. REC-2: Petroleum Odor Noted During Geotechnical Investigation At total of 15 geotechnical soil borings were advanced along the Project Corridor in 2019 in preparation for roadway improvements. The borings were advanced to 14.5 feet below grade and approximately every 400 linear feet along the Project Corridor. While completing the borings, an “apparent hydrocarbon odor” was noted in 11 of the 15 boring locations at depths ranging from 0.3 to 14.5 feet below grade. No analytical soil samples were collected during the geotechnical investigation. The presence of petroleum odors noted throughout the Project Corridor during the 2019 Geotechnical Investigation is considered a REC. 8.2 Historical Recognized Environmental Conditions The ASTM E1527-13 Standard defines the term historical recognized environmental condition (HREC) as meaning “a past release of any hazardous substance or petroleum products that has occurred in connection with the Project Corridor and has been addressed to the satisfaction of the applicable regulatory authority or meeting unrestricted residential use criteria established by a regulatory authority, without subjecting the Project Corridor to any required controls (e.g., Project Corridor use restrictions, Activity and Use Limitations (AULs), institutional controls, or engineering controls). Before calling the past release a HREC, the environmental professional (EP) must determine whether the past release is a REC at the time the Phase I ESA is conducted (e.g., if there has been a change in the regulatory criteria). If the EP considers this past release to be a REC at the time the Phase I ESA is conducted, the conditions shall be included in the conclusion section of the report as a REC.” Based on this assessment, no HRECs were identified in connection with the Project Corridor. 8.3 Controlled Recognized Environmental Conditions The ASTM E1527-13 Standard defines the term controlled recognized environmental condition (CREC) as meaning “a REC resulting from a past release of hazardous substances or petroleum products that has been addressed to the satisfaction of the applicable regulatory authority (e.g., as evidence by the issuance of NFA letter or equivalent, or meeting risk-based criteria established by regulatory authority), with hazardous substances or petroleum products allowed to