Are All Phase I ESAs Equal?

When Reg. 153 was updated in 2011, the Ministry of the Environment and Climate Change (MOECC) changed from general guidelines for Phase I ESAs to carefully prescribed rules. While the principal components are the same the Regulation now gives a detailed description of steps required including objectives and requirements for each component. These rules are meant to standardize a Phase I report and improve quality for a RSC submission and filing.

The result of these rule changes however is that in certain circumstances (most notably for environmental due diligence during real estate transfers) there is not enough time to complete all the steps required for a Reg. 153 compliant Phase I ESA. In those instances a decision must be made on how to proceed with the environmental site assessment so as not to compromise the objectives of the project.Contaminated site in Northern Quebec

The Canadian Standards Association (CSA) developed a set of standards for Phase I ESAs in Nov. 2001 with the latest edition reaffirmed in 2012. When Reg. 153 was updated in 2011 any cross-references to the CSA Phase I ESA requirements were replaced with detailed stand-alone rules, making a Reg 153/04 Phase I document standardized.

The only time a Phase I ESA is required to be Reg 153 compliant is when an RSC is submitted to the MOECC in support of a change of property to a more sensitive land use. Other interested parties including owners, lenders, insurers, or municipalities can determine their required compliance to Reg. 153 at their discretion.

In many cases (e.g. real estate transaction, financing, etc.) a CSA compliant Phase I ESA is adequate. As a Reg. 153/04 compliant Phase I ESA generally has more stringent requirements and thus higher costs associated with it, it is essential that the Phase I ESA requirements be clearly defined by the party requiring the ESA.

The general components of a Phase I ESA are the same for Reg 153/04 and CSA, and include: records review, interviews, site reconnaissance, and evaluation of information and reporting. Specific details of components are not always defined under the CSA standard as it applies across Canada while Reg. 153 applies only to Ontario.

Some of the differences between a Reg 153/04 and CSA Phase I ESA are listed below (not a comprehensive list, but highlights some differences):

O. Reg. 153/04 Phase I ESA


Qualified Person: The person conducting or supervising the Phase I must be a QP as defined under the Reg.

Competence of the Assessor: Not strictly defined, but must be competent to complete a Phase I ESA.

Phase I ESA Study Area: Minimum of 250 m from the nearest point on a boundary of the Phase I property

Phase I ESA Study Area: Minimum of adjacent neighbouring properties

Chain of Title: Back to first developed use

Chain of Title: Required, but no specifics

Environmental Source Information: all reasonable inquiries must be made to obtain national pollutant release inventory (NPRI) information, PCB information, retail fuel storage information,  identification of area of natural significance (ANSI’s), MOECC records including inventory of coal gasification plants, Environmental Compliance Approvals (ECAs), environmental incidents, waste management records, landfill information

Environmental Source Information: regulatory information including (generally) permits, violations, work orders, prosecutions

Physical Setting Sources: aerial photos dating back to first developed use, topographic maps, physiographic maps, geological maps, and wells records

Physical Setting Sources: aerial photographs

Review and evaluation of information: A Qualified Person is required to prepare an  APEC table, current and past uses table, and  conceptual site model (CSM), in addition to the required report sections

Review and evaluation of information: No specific documents, outside of the written report, are required.

Within the flexibility of the CSA standard further customization of the report requirements can be considered in order to meet project cost and time constraints:

Phase I ESA Component

Potential Approach

Qualified Person/Competent Assessor

For work in Ontario a QP is recommended even for CSA oriented reports.

Phase I ESA Study Area:

250 m search radius from the nearest point on a boundary of the Phase I property.

Chain of Title:

Initially confine title searches to the electronic Land Titles System. In the Land Titles System, the Province has custody of all original titles, documents and plans and has the legal responsibility for the validity and security of all registered land title information. Since this record is updated each time a land registration document is registered, only a search of the current register of interests (and not all documents registered during the 40 preceding years) is required in order to ascertain title. As of March 2011, approximately 99.9% of properties in Ontario were recorded under the Land Titles System in electronic form. In some instances of long held land use a more detailed title search may be required.

Environmental Source Information:

Initially restrict source information to the basic EcoLog ERIS property inform ation package which includes (please list).

For properties developed prior to 1980 the addition of fire insurance maps is also important (fire insurance maps were discontinued in the 1970’s).

Physical Setting Sources

A representative selection of aerial photos is recommended. Physiographic and geological maps are also readily available.

Freedom of Information Requests

FOI requests require a minimum of 30 days to receive responses, generally beyond the decision making scope of the Phase ESA in some instances.

Confirmation of approval to apply non-potable groundwater use at the site.

Groundwater use affects the level of “cleanup” required at the site but needs to be confirmed by the municipality (45 day reply period) if the intended use is non-potable. Often this can be confirmed verbally or based on the experience of the QP

Review and evaluation of information:

APEC and current and past uses tables prepared by a Qualified Person is recommended. A basic CSM for the site is also recommended.