Environmental Site Assessments

Environmental Site Assessments

When developing a property, avoiding costly delays is critical for success. If a parcel of land is known, or suspected, to be contaminated, the Environmental Site Assessment (ESA) process is used to identify potentially contaminating activities (PCAs), ascertain Areas of Potential Environmental Concern (APECs), determine concentrations of Contaminants of Concern (COCs), and develop a strategy to address/remediate identified environmental issues.

At Terrapex, our team of professional engineers, geoscientists, environmental scientists, and technicians work with you to provide personalized, economical, and practical approaches to ensure ESAs are completed in a cost-efficient and timely manner.

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A Phase I or “Phase One” ESA is a non-intrusive investigation that determines the environmental conditions of the property and identifies any issues of actual or potential environmental concern such as Potentially Contaminating Activities (PCAs). Based on these findings, the Phase I ESA identifies any Areas of Potential Environmental Concern (APECs) on the property that should be investigated and the corresponding contaminants of potential concern.

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A Phase II or “Phase Two” ESA then investigates soil and groundwater conditions (and possibly sediment, surface water or air) at the identified APECs. Concentrations of Contaminants of Concern (COCs) in collected samples are then compared to applicable site condition standards/environmental criteria to determine the location/extent of contamination. A determination is then made to either develop remedial (clean-up) plans with obtained data or to investigate the site further.

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In situations where the extent of subsurface contamination is not fully understood or other data gaps exist regarding subsurface conditions, supplemental Phase II investigation (sometimes identified as a “Phase III ESA”) is undertaken. The full vertical and horizontal extents of identified soil and groundwater impacts are delineated and additional data on site conditions (such as soil porosity, grain size etc.) is collected. This information is then used to develop a remedial work program for the property.

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