Lead tailings are present in Northampton as the result of them being used opportunistically for fill and foundation materials over the past several decades. The tailings, which are visually distinct from natural soils, contain concentrations of lead and other heavy metals which are potentially significant to human health. The Northampton Lead Tailings Project (NLTP) has phased its approach to investigate the entire town to understand the distribution (Phase 1) and remediate or manage tailings to mitigate potential health risks (Phase 2).
Aurora Environmental completed Phase 1 of the NLTP, with a desktop review of available literature and previous studies and designed a plan to investigate >750 properties. The investigation methodology included interviews with owners/occupiers, property inspections, site photography, soil sampling and analysis of soils through the use of field portable X-Ray Fluorescence (XRF) devices. Subsequently, Aurora Environmental developed and managed a project-specific relational database.
Concentration of metals and other elements in the soil data were reviewed for potential risks to human health. 692 properties were assessed and a preliminary remediation plan for Phase 2 was developed. Properties suspected as having soils impacted by tailings were passed into Phase 2.
The project also required related studies into the natural background concentrations of heavy metals and the bioaccessibility of lead from samples of tailings, natural and other urban soils.
Key services provided:
- Property inspections, interviews, soil sampling, XRF measurements
- Community engagement for nine months with a high degree of interaction
- Data management
- Risk assessment
- Remediation planning and cost estimation
- Contamination assessment and reporting with summary reports for each property
- Liaison with Government agencies, Northampton Shire, the Auditor
- Presentations to the Steering Committee.