Project Value: c.$50,000

SLP personnel were responsible for undertaking detailed quantitative risk assessment modelling to assess the human health risks associated with the redevelopment of a closed landfill into a school end use. 

The client understood the sensitivities associated with the redevelopment proposals and commissioned a Phase 2 intrusive investigation supplemented by comprehensive human health risk assessment modelling. The ultimate objective of the assessments was to ensure that all the relevant pollutant linkages associated with the proposed change of use were clearly identified in order that the appropriate risk management measures could be implemented.

The modelling confirmed that concentrations of polychlorinated biphenyls (PCBs) and BTEX compounds recorded in the Vadose Zone soils represented an unacceptable risk to the human health of the school users. The primary exposure pathways comprised:

• Inadvertent ingestion/inhalation of contaminated soil particles
• Dermal contact with contaminated soils
• Vapour intrusion to indoor air and inhalation of Volatile Organic Compounds (VOCs) 

With the relevant pollutant linkages identified the designers were able to incorporate sufficient risk management measures into the construction of the buildings to ensure that the pollutant linkages were broken and the human health risks reduced to acceptable levels. The risk management strategy was accepted by regulators and stakeholders alike, and the school is now under construction.