What Is Environmental Risk Assessment?

Despite their best efforts to ensure that their properties are clean and free from environmental impacts, land owners occasionally find (through a Phase II ESA) that their property has some kind of contamination in the soil or groundwater. Their property is no longer compliant with O. Reg. 153 and they have environmental liability that needs to be managed.

If this is the case for you, what can Risk Assessment do to reduce your liability and help you bring your site into compliance?

Risk Assessment is, most simply, the analysis of hazards and the likelihood of them causing issues. An Environmental Risk Assessment is a structured analysis of environmental impacts (like contamination in groundwater or soil) and the probability that these will harm plants, animals, the surrounding environment, or humans.

A Risk Assessment looks at these impacts, hazards, and probabilities and proposes site-specific standards that take into account the use of the site, the unique site features, and the current allowable guidelines to propose new standards for the site. Regulatory officials (in Ontario, the MOE) review and accept or reject these standards.

Environmental Risk Assessment is carried out by a Qualified Person (QPRA) who can calculate the probability of harm under certain environmental conditions. This looks at the dosage of a contaminant needed to cause harm, and the ways that exposure could happen at the site. For instance, a Risk Assessor could examine levels of lead in the soil, calculate the probable exposure that a construction worker would face if he was digging all day, and determine whether this is an acceptable level of risk or if a Risk Management Measure is needed.

A Risk Management Measure (RMM) protects people using the property from exposure to the contaminant in question. RMMs can take a variety of forms. One common RMM on environmental sites is the use of a barrier to keep the impacted soil contained. This could be an asphalt pad covering contaminated soil and used as a parking lot. Another RMM could be using the first floor of a building for non-residential purposes (shops or parking instead, perhaps), so residents aren’t exposed to soil impacts.

RA is a form of remediation and is a piece of the land restoration puzzle. Often, it is financially or logistically difficult to bring sites into compliance with the standard criteria/regulations. RA can be one tool in the QP’s toolbox for bringing value back to these sites.

The RA process is more prescriptive under the new EPA provisions and RSC Regulations (released in 2011). This ensures a more rigorous process and significantly reduces the risk exposure to the property owner.

AEL believes in using RA in conjunction with other approaches. On many sites, this means remediating “hotspots” or areas of high contamination, and using risk assessment to adjust the allowable limits for the site. This is useful when there is widespread, low-level contamination. This saves the you, the client, time and money, preventing unnecessary excavation and disposal fees.