Pinchin LeBlanc Environmental Ltd. - Representative Projects

Qualitative Risk Assessment (QRA) and Site Management Plan for a commercial site in Moncton, New Brunswick

A Tier II assessment and Qualitative Risk Assessment (QRA) was conducted on a commercial property located in Moncton, New Brunswick. The QRA was based on the results of a Phase II Environmental Site Assessment (ESA) at the site which identified soil impacted with Modified Total Petroleum Hydrocarbon (TPH) at concentrations above applicable guidelines. Soil impacted with various metal and polycyclic aromatic hydrocarbon (PAH) concentrations above applicable guidelines, was identified. Groundwater, impacted with metal and PAH concentrations above applicable guidelines, was also identified. Through the Tier II assessment, it was determined that the Modified TPH concentration in the soil was within the Site Specific Target Levels (SSTLs) developed for the Site. As part of the Tier II risk assessment, individual and cumulative contaminant of concern target risk values, hazard quotient and hazard index limits were established to be at acceptable levels.

Qualitative Risk Assessment (QRA) and Site Management Plan Target risk values and hazard quotient limits were met for the critical exposure pathways. The hazard index limit for the critical exposure pathway (indoor air) exceeded the established limit. A Tier III risk assessment of the indoor air exposure pathway was required to address the hazard index exceedance. This entailed sampling indoor air in the basement of the building. The hydrocarbon concentrations from the air samples were compared to Risk Based Screening Levels (RBSLs) for indoor air. Hydrocarbon concentrations in the indoor air of the basement of the building were within RBSLs established through the Tier II assessment of the site.

The risk associated with the metal and PAH impact of the surface soil on the Site was determined to be acceptable through the maintenance of the asphalt cover of the Site.

The risk associated with the metal and PAH impacted groundwater on the Site was determined to be acceptable as there were no habitats of potential concern identified within 150 metres of the Site.

Based on the Tier II and Tier III Assessments, and QRA, a Site Management Plan was developed which was acceptable to the Provincial Department of Environment and Local Government.