Determine if a Site is Contaminated
Screening a site can be the first step in determining if it’s contaminated or not – this process involves the creation of a site profile. A site investigation is almost always required if the screening indicates there’s potential for contamination.
The site profile form summarizes information about potentially contaminated sites – including a basic description of the site and an overview of its past and present uses. Typically a site profile is created during a screening and is completed by a site owner or qualified consultant.
Site investigation is the primary method used for gathering detailed information about potentially contaminated sites. Land owners can have an investigation done without government involvement, but it should be carried out by experienced consultants. Under legislation, the Director of Waste Management at the Ministry of Environment can order a site investigation when prompted by a site profile or other information.
Site investigations can be done in two stages – sometimes both are combined:
- Preliminary investigation: Searching existing records for information about a site, interviewing people who are or have been involved with the site, and determining the general location and degree of any contamination
- Detailed investigation: When full information is required, investigators work to determine the location, extent and impact of contamination – information from this phase is usually sufficient to develop a remediation plan, or a human health / environmental risk assessment
Environmental Standard Comparison
After a site is investigated, the findings are analyzed and compared with the environmental quality standards set out in the Contaminated Sites Regulation.
The legislation categorizes standards using:
- Numerical standards: Acceptable concentrations of substances in soil, surface water, groundwater, vapour and sediments
- Risk-based standards: Acceptable risk levels from exposure to substances at sites
These standards are used to:
- Determine if a site is contaminated
- Determine when a site has been adequately cleaned up
- Determine when soil relocation may occur
- Identify potential safety hazards