Phase 1 ESA Search Distances – Part 1

I have had a few discussions recently with colleagues and clients regarding applicable search distances when completing the Records Review portion of a Phase I Environmental Site Assessment. Since the extent of data to review significantly affects the assessment of potential environmental risks for the ESA Property, it is important to understand the criteria that impacts the determination of the ESA Study Area. Before I discuss these implications for the assessor and stakeholders, we have to consider the applicable environmental standards and regulatory requirements for conducting Phase I ESA. Below, I have summarized some of the most common guidance documents and regulations regarding records review search distances for Phase I ESA.

Canadian Standards Association (CSA): Canada’s national ESA Guidelines (CSA-Z768) do not specific an actual search distance for the Phase I ESA Records Review, instead stating: “Since neighbouring properties may affect, or be affected by, the property being assessed, appropriate search distances shall be determined and documented in the scope of work. The subject property shall require a records review …(as prescribed)… As a minimum, adjacent properties shall require a review of reasonably ascertainable records and publicly available records …..”

British Columbia: In BC, a Stage 1 Preliminary Site Investigation (PSI) generally follows the CSA Standard for Phase I ESA; except the Records Review is required to include properties located within 250 m of the PSI Property, and for Provincial Site Registry Records to be searched to a distance of 500 m.

Alberta: The Records Review for conducting ESA in Alberta for both Upstream Oil and Gas sites and Commercial/Industrial-type ESAs are generally similar to CSA for the Site and adjacent properties, plus requirements for some records review to include properties located within 300 m of the Phase 1 Property (NPRI, Landfills, Aerial Photos, Physical Settings data and maps). 

Ontario: For non-Record of Site Condition ESA (i.e. due diligence), the CSA guidance for search distances is still applicable. However, when an RSC is needed, the RSC regulations in Ontario (OR 153/04, as amended) require a records review to include all properties located, wholly or partly, within 250 metres from the boundary of the phase one property. The Qualified Person (QP) must look at all properties within the 250 metres boundary, and must also consider properties beyond 250 metres to determine if any such property may be contributing to an APEC on the phase one property.

Atlantic Canada: Generally speaking Phase I ESA conducted in the Maritime provinces follow the CSA Standard, and the search distances specified therein. Under the Atlantic RBCA (Risk Based Corrective Action) regulations, there can be requirements to identify potential environmental receptors located within 150 m of an ESA property with petroleum-related concerns or activities. Individual provinces may have slight regulatory variations for their ESA requirements, so it is important to confirm any specific requirements of that province.

ASTM: The American Society for Testing and Materials (ASTM), standard for conducting Phase I ESA (ASTM Standard E1527-21), specifies different records review search distances based on the type of database, with the most common distances ranging from 1/8 mile to 1 mile and sometimes more for specific federal or state databases (e.g. 1/8 to ¼ mile for local/county/municipal data; ½ mile for frequently used federal and state records; and 1 mile for more significant databases like Superfund and hazardous waste sites).

The above list is not all-inclusive and there may be additional, or non-standard requirements for some ESA properties and other jurisdictions. Next month I will discuss implications of these variable search distance requirements and real-world considerations and limitations of this aspect of the records review process.

Bill Leedham, P. Geo., CESA
Bill is the Head Instructor and Course Developer for the Associated Environmental Site Assessors of Canada (www.aesac.ca); and the founder and President of Down 2 Earth Environmental Services Inc. You can contact Bill at info@down2earthenvironmental.ca