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Phase I Environmental Site Assessments

What is a Phase I Environmental Site Assessment?

A Phase I Environmental Site Assessment is a non-intrusive qualitative examination of a property and of any documentation related thereto that might provide factual insight into the property’s past and present uses in terms of the propensity for environmental impact on the site.

Background Information

Property owners, purchasers, lenders and tenants may face unforeseen liabilities when dealing with properties for which the environmental history is unknown. These liabilities arise from litigation associated with contamination, restrictions on development, loss of land value (due to contamination/perceived contamination), and / or government initiated orders. The information from a Phase I Environmental Site Assessment (ESA) can be used by property owners, tenants, purchasers, and lenders to make informed decisions.

The need to actively manage environmental issues related to estate in Canada came to the forefront over the past few decades. During that time, passage of legislation placed accountability for the environmental impairment of a property on its present owner, regardless of which party was actually responsible for creating the impaired condition.

No longer able to overlook the potential liability that may be linked to a property’s environmental condition, buyers, lenders, receivers and other interested parties soon required that a property’s probability of contamination be determined in advance as accurately and as completely as economically permissible. Generally, the largest portion of the burden for flagging environmental risks fell upon purchasers. However, the ‘due diligence’ process soon began to extend to self-assessment and disclosure as a device for terminating a vendor’s environmental obligations.


The purpose of a Phase I ESA is to identify actual and potential Site contamination through historical research, interviews, and observations made during a walk-through of the property and surrounding area. The Phase I ESA is a qualitative assessment, which may be used to structure further intrusive investigation, if warranted (i.e. a Phase II ESA). A Phase I ESA can be used to identify existing and historical Potentially Contaminating Activities (PCAs) and their associated Potential Contaminants of Concern (PCOCs). PCAs are activities that may lead to adverse impacts (i.e. contamination) to the soil, groundwater, and sediment regimes, due to the nature of the activities, and through accidental spills, leaks, and mishandling of materials containing PCOCs.  PCAs may be associated with on-site Areas of Potential Environmental Concern (APECs) (i.e. represent an area where actual or potential contamination exists).  The existence of an APEC is subject to interpretation by qualified professionals and is dependent on a number of factors which may include the nature of the PCA, scale of the PCA, and its relative location to the property with consideration to distance, topography, and hydrogeology.

In Ontario there are two main standards under which Phase I ESAs are conducted and evaluated. The first is the Canadian Standards Association (CSA) document Z768-01 dated November 2001 and reaffirmed in 2016. CSA Phase I ESAs are typically requested to support the sale of a property or for financing purposes.  The second standard is Ontario Regulation 153/04, made under Part XV.1 of the Environmental Protection Act. O.Reg. 153/04 Phase I ESAs are typically requested to support the redevelopment of a property to a more sensitive use and the filing of a Record of Site Condition (RSC).

The specific standard to which the Phase I ESA is conducted will depend on the client’s individual needs and intentions.


Site Visit
A Phase I ESA is strictly qualitative in nature and does not include intrusive sample collection and analysis. It will be necessary for a representative from JFM Environmental Limited (JMFEL) to access the entirety of the property, including any buildings that may be present on-site. A site representative may be required to accompany JFMEL during the visit to answer questions pertaining to historical usage of the property and features that may be observed. JFMEL personnel will take photos and notes throughout site reconnaissance to be used as references in preparing the Phase I ESA report.

JFMEL will obtain and review historical information that is readily available and pertains to the site’s environmental history (ie. through public and institutional libraries, online maps and databases, client supplied documentation, etc.). Documents reviewed include; historical aerial photographs, fire insurance plans, topographic maps, and municipal street directories. The reviewed documents are used to establish the historical usage of the site and surrounding area. Interviews with site representatives and other individuals with knowledge of past and present usage of the site will be conducted to further develop the history of the site and surrounding area.

As part of the Phase I ESA process information requests regarding the subject property are submitted to the Ministry of the Environment, Conservation and Parks (MECP), the local / regional municipality, and the Technical Standards and Safety Authority. The requests are focused on identifying; environmental concerns, violations, orders, approvals, and investigations; spill records; waste generator and receiver records; records of tanks, and landfills; and, other records relevant towards the completion of the Phase I ESA.

Following completion of the site visit and records review, the information will be assessed and compiled into a Phase I Environmental Site Assessment Report. The reports are structured around the standards used, and include an executive summary which presents the interpretation of the findings and relevant conclusions and recommendations.

JFM’s team of highly qualified professionals is well versed in the conduct of the entire suite of Phase I, II and III Environmental Site Assessments, and to all applicable legislative and industry standards. Our work is relied upon by numerous investor groups, financial institutions, governments, and a wide variety of privately and publicly held industrial and commercial clients. If you would like more information please feel free to contact us or fill out a no obligation consultation form.

Please click here for more information on Phase II Environmental Site Assessments.