Environmental Site Assessment

Understand the ground you build on

As a property owner or developer, you need to fully identify and understand the subsurface environmental risks you may be assuming. Our expertise can help you avoid legal and regulatory surprises. To determine risk, you may choose (or be required) to conduct an Environmental Site Assessment (ESA) or Contaminated Site Assessment on the property.

open field and sunny sky

We help you understand and manage subsurface environmental risks for both  developed properties (brownfield sites) or undeveloped properties(greenfield sites) through a complete range of services: assessment, remediation planning, monitoring, and formal recording of compliance.

The following are some situations where a thorough environmental or contaminated site assessment may be valuable or required:

  • as part of a property acquisition 
  • for the purposes of internal corporate due diligence
  • as a requirement of a facility’s operating permit (compliance monitoring) 
  • where activity or natural processes at the site could create risks at a neighboring site, or vice versa.

How we work

Phases of Assessment

  • Phase I/One Environmental Site Assessment.
    A Phase I assessment is an effective tool in determining whether the potential for an environmental problem exists at a site or not. The process includes a review of practically available historical documents for both the site and the surrounding properties, a thorough site reconnaissance to evaluate existing conditions of a property, and interviews with knowledgeable site representatives and/or willing neighbors and past owners.
  • Phase II/Two Environmental Site Assessment.
    A Phase II assessment builds upon the results of a Phase I ESA to confirm whether there is (or is not) a problem at a site. A Phase II ESA can include both nonintrusive and intrusive sampling programs to address any potential contaminating activities (PCAs) noted within the Phase I ESA. Nonintrusive sampling is typically prescreening with electromagnetic or ground penetrating surveys; instrusive sampling can include drilling, test pit advancement, and sampling of soil/groundwater/surface water/soil vapor, as appropriate. An analytical testing program is typically carried out to verify concentrations of contaminants of concern and compare them to regulatory criteria.
  • Phase III Environmental Site Assessment and Remediation Action Plan Development.
    A Phase III assessment is conducted to determine how big a problem is at a site. Intrusive and/or nonintrusive investigations are undertaken to delineate the extent of contaminants as verified by the Phase II ESA.

ground water testing

Remediation Planning and Monitoring

  • A plan is developed to fix the problem. An appropriate remedial action plan is developed on the basis of the extent and nature of the contamination found in the assessment. A verification sampling program is carried out to monitor the remedial effort and assess the effectiveness of restoration efforts.

Record of Site Condition

  • A further step is also required in some cases: filing a Record of Site Condition (RSC). Under Ontario Regulation 153 (O. Reg. 153/04), the Ontario Ministry of the Environment, Conservation and Parks requires a land owner to file an RSC if land use changes from a less sensitive use (industrial, commercial) to a more sensitive use (residential, parkland). We have “Qualified Persons” on staff who are authorized to file an RSC upon completion of either the phased site assessment described above and/or a remediation process. Under certain circumstances, the local municipality may also require an RSC.

What sets RWDI apart:

  • Technical excellence.
    Our commitment to exceptional quality carries though the entire assessment, remediation and reporting process. Every assessment is under the active guidance of a senior professional with experience in identifying unusual or complex issues, and work is always reviewed by credentialed staff (P.Geo, P.Eng, and Qualified Person).
  • Breadth of expertise.
    When a problem is found, we draw on expertise from throughout the company to develop a mitigation strategy. For example, our experts in ventilation can advise on dealing with accumulated or migrating vapor. We excel in solving complex issues, such as supporting a legal action involving external contamination from two sources or devising remedial action plans to address multiple contaminants.