- Contaminated Land on Residential Properties: Health risk, Environmental risk or Financial Risk?
The environmental liability associated with contaminated residential properties in Montreal is close to 30 billion $. The contaminated areas would occupy about 27% of the territory. Since February 2017, the Canada Mortgage and Housing Corporation provides loan insurance, on a case by case basis, on residential properties with non-conforming soils based on toxicological and ecotoxicological opinion. For its part, the ministère du Développement durable, de l'Environnement et de la Lutte contre les changements climatiques has chosen to focus its intervention on industrial activities covered by the Contaminated Sites Protection Regulation. The issue of contaminated land in residential settings needs to be discussed among stakeholders in order to define a clear and transparent way to adequately manage financial risks for buyers, sellers and lenders, as well as the risk for the health and for the environment. During this conference, several solutions will be put forward.
- Human Health and Ecological Risk Assessment and Technical Infeasibility in Contaminated Site Management
Human health and ecological risk assessment has been used for over 20 years as an alternative in contaminated site management. In contrast to the majority of North American jurisdictions, the use of risk assessment in the presence of petroleum hydrocarbon or VOC contamination is not permitted in Quebec. The site must then be remediated to the generic usage criteria. We present examples of sites contaminated with petroleum hydrocarbons or VOCs, and for which a combination of traditional remediation, in situ treatment, risk assessment and technical infeasibility have allowed the remediation and development of the sites. The sites presented problems that made traditional remediation inadequate or technically impractical, including the extent and depth of contamination, and where in situ treatment effectiveness had reached its limits.
- Geophysics, a tool in the investigation of contaminated lands that reduces uncertainties
Geophysics is a powerful tool for the characterisation of contaminated sites. It allows to cover an important land surface at a reasonable cost, and can bring many useful complementary information.
Geosphysics can be the link to complete the missing parts of the history of a contaminated site, some information being lost through time. Different approaches allow the acquisition of a representation of soils or polluted areas. Geophysics can also be used to identify underground structures, pipes, etc. that will lead to a better management of the field work and an increase in the field crew's security. On top of that, a good characterisation of the field with geophysics makes more efficient the conduction of the field work (g.e implementation of boreholes), leading to cost optimization and a reduction of the financial risk for consultants.
We worked on many cases that, in terms reduced uncertainties in the environmental assessment of contaminated lands