Environmental Site Assessments

Environmental Site Assessments


Environmental Site Assessments (ESAs) are a Cambium primary area of expertise. Our Professional Engineers (P.Eng.) and Professional Geoscientists (P.Geo) have vast experience conducting ESAs that meet Canadian Standard Association (CSA) and Ontario Regulation (O.Reg.) 153/04 requirements.

Our team of O.Reg. 153/04 Qualified Persons (QPs) undertake and manage ESAs for private, public, and government organizations. Cambium is an approved vendor with numerous financial institutions to provide consulting and ESA services as required for real estate transactions. We work with our clients to identify and manage their environmental risk.


What is an Environmental Site Assessment (ESA)?

An ESA is a carefully managed assessment of site conditions to identify potential or existing environmental contamination. An ESA is used to identify potential liabilities, assess extent of impact, and provide supporting data for remediation or risk assessment.


Two Types of ESA


Phase I ESA

A Phase I ESA is a non-intrusive investigation during which Cambium staff use their knowledge and expertise to identify actual and potential areas of environmental concern and contamination. A Phase One ESA is undertaken consistent with CSA Z768-01 for real estate transactions and other dues diligence requirements. A Phase I ESA is conducted consistent with O.Reg. 153/04 to support filing an RSC to allow a change in property use from a less sensitive to more sensitive use (e.g., commercial to residential). Phase I ESAs are based on the information gathered during a site inspection, records review, and interviews with individuals that have specific knowledge of the subject property.

During the site inspection, the subject property and surrounding properties are observed to identify environmental concerns such as:

  • Underground and above ground storage tanks (USTs and ASTs)
  • Materials handling, storage, and disposal practices
  • Hazardous materials
  • Potential contaminants of concern
  • Potential contaminant migration pathways

Why is a Phase I ESA required? A Phase I ESA report is often requested by a financial or lending institution as a requirement for a real estate transaction to purchase industrial, commercial, and multi-unit residential buildings. A Phase I ESA report provides an environmental record of the subject property. This type of investigation is also beneficial for use prior to major renovations or changes in the type of activity taking place on a property.

How much does a Phase I ESA cost? The cost is site-specific, as each location differs from the next in terms of property type, size, and location. Other factors that affect the price include the purpose of the assessment and which standard the ESA process will follow.


Phase II ESA

A Phase II ESA is an intrusive investigation used to confirm the presence or absence of potential contamination identified by a Phase I ESA, to delineate previously identified contamination, to support remediation, risk assessment, identification of risk management measures, and/or filing an RSC. Subsurface soil and groundwater investigation activities involved in the completion of a Phase II ESA may include:

  • Excavation of test pits
  • Installation of boreholes or monitoring wells
  • Hydrogeological assessment
  • Collection and analysis of soil, sediment, groundwater, or surface water samples
  • Soil vapour sampling
  • Indoor air sampling

The results of the Phase II ESA define the nature and extent of contamination present at the subject property. In cases where the nature of activities - current or historical - occurring on the subject property or on adjacent properties indicates a probable source of contamination. The investigation and resultant report completed by Cambium for Phase II ESAs are based on the Canadian Standards Association Standard Z769-00 or O.Reg. 153/04 requirements depending on the objective of the investigation.

How much does a Phase II ESA cost? As with the Phase I, the costs for a Phase II ESA are site-specific and vary depend on the property, the contaminants of concern identified by Phase I ESA, and the extent of impact.

What types of properties require a Phase II ESA? A Phase II ESA is required at properties where historical or current activities have potentially contaminated soil, sediment, groundwater, or surface water. Phase II ESAs are typically required for gas service stations, auto body repair and services garages, dry cleaners, maintenance yards with ASTs or USTs, industrial facilities, etc.

Remediation ESAs often lead to a remediation of an impacted site by one or more of the following methods – excavation, pump and treat, insitu treatment, monitored natural attenuation. Please see our Site Remediation and Restoration page for more details on services we can provide.


Records of Site Condition (RSC)

Cambium can prepare and submit an RSC utilizing our team of qualified professional engineers, hydrogeologists, geoscientists and GIS experts. The province of Ontario, through the Brownfields Statute Law Amendment Act, 2001 (https://www.ontario.ca/laws/statute/S01017), requires mandatory filing of an RSC for prescribed changes in property use. Some municipalities may also require an RSC for substantial property re-development where a change in property use is not intended.