Pathway Exclusions / Guideline Modifications
In Alberta, the Alberta Soil and Groundwater Remediation Guidelines allow exclusion of pathways. Beyond that, guideline modifications are accepted for basic petroleum hydrocarbons and polycyclic aromatic hydrocarbons
Chloride concentration guidelines can be modified through the use of the Subsoil Salinity Tool to accomodate site-specific guidelines. Beyond that, a risk-based assessment is used.
In BC, the Contaminated Sites Regulation does not allow modifications to the standards but does allow pathway exclusions. Beyond that, risk-based approaches are allowed..
Risk assessment involves identifying site-specific contaminant sources, pathways, and receptors that are present. By using calculations, field tests, and/or toxicological studies, the risk at a site can be reduced or removed.