Phase I and Phase II Environmental Site Assessments
In August 2020, XCG was retained by Penta Equipment Inc. (PEI), the owner of 260 Centre Street, Petrolia, Ontario (subject site) to review information and data generated during a Phase I and Phase II Environmental Site Assessments (ESAs) completed on the subject site in 2007. The review of the 2007 information and data indicated that soil (fill) and shallow groundwater on the subject site have been impacted with metals, petroleum hydrocarbons (PHCs), polycyclic aromatic hydrocarbons (PAHs), volatile organic compounds (VOCs), and polychlorinated biphenyls (PCBs). These impacts were primarily located in the fill and potentially in the upper portion of the underlying native clay, The full extent of the impacts was not delineated during the 2007 Phase II ESA.
In February 2021, XCG was retained by PEI to complete a Phase I ESA on the subject site. The February 2021 Phase I ESA did not identify any new (since the 2007 Phase I ESA) potential or actual sources of impacts to soil and/or groundwater on the subject site.
In early 2022, PEI retained XCG to complete a Phase II ESA. The purpose of this Phase II ESA was to further investigate and delineate the vertical extent of impacts to the on-site soil and groundwater quality that were previously identified in 2007, and to determine if the on-site soil and/or groundwater impacts could affect the ongoing use of the subject site for commercial/industrial purposes.
To achieve the project objectives, the Phase II ESA scope of work included excavation of 25 test pits and completion of 16 boreholes across the subject site, instrumentation of all 16 boreholes as groundwater monitoring wells, collection, and screening of soil samples for evidence of impacts, surveying of all monitoring wells to an on-site, development, purging and sampling of wells using low flow/low volume method. Submission of one ‘worst-case’ surface soil/fill sample and one (first) underlying ‘clean’ soil sample as well as groundwater samples for laboratory chemical analysis of one or more of the contaminants of concern (COC), including metals, PHCs (F1 to F4), PAHs, VOCs, and/or PCBs.
To assess the soil and groundwater quality, based on the site use and setting, the sample analytical results were compared to the Stratified Site Condition Standards (SCS) in Non-Potable Groundwater Condition (Table 5), Commercial Property Use, Medium- to Fine-grained Soils published by the MOE in a document titled “Soil, Ground Water and Sediment Standards for Use Under Part XV.1 of the Environmental Protection Act,” dated April 15, 2011 (MOE Generic Standards). In order to assess if the detected concentrations of the COCs would affect the ongoing use of the subject site for commercial/industrial use, the soil and/or groundwater samples that exceeded the Table 5 MOE Generic Standards, were also compared to applicable, human health-based component values (HHBCV) published by the MOE in a document titled “Rationale for the Development of Soil and Ground Water Standards for Use at Contaminated Sites in Ontario,” dated April 15, 2011, updated on November 1, 2016, (MOE Rationale Document).
Based on the assessment of the soil and groundwater sample analytical results, XCG concluded that there was evidence that the COC-related impacts to the on-site soil have the potential to affect the ongoing use of the subject property for the ongoing commercial or industrial use. This conclusion was based on the fact that most (42 of the 46) of the soil samples collected across the subject site were reported to have concentrations of PHCs (F1 to F4), VOCs, PAHs, metals, and/or PCBs that were above the applicable HHBCVs. XCG also concluded that, although there were several monitoring wells where the groundwater concentrations of COCs exceeded the Table 5 MOE Generic Standards, only one well had concentrations of COCs that exceeded the applicable HHBCVs. Given the location of this well, XCG concluded that the elevated concentrations of COCs in groundwater across the subject site are not likely to affect the use of the subject site for continued commercial/industrial purposes.