A townwide study into the presence and remediation of lead tailings – Northampton, WA (AU))

Lead tailings resulting from local mineral processing were opportunistically used as a fill material during development of Northampton, primarily during the period 1950-1980. The tailings contain significant concentrations of lead (and other heavy metals such as arsenic, copper and zinc) which can cause potentially unacceptable health risks to people who may be exposed to tailings where they have been used as fill on residential, recreational and commercial properties. Following on from various previous studies and clean up works conducted by Government (on a somewhat ad hoc basis) since the early 1980's, most people living in Northampton are aware of the presence of tailings and the possible adverse health effects. However, the distribution of tailings and the number of properties affected had not previously been defined. In 2013, the State Government (Department of Lands, DoL) commissioned Aurora Environmental (Aurora) to conduct the first consolidated town-wide review and investigation to establish the extent of the issue as Phase 1 of the Northampton Lead Tailings Project (the NLTP). Aurora worked collaboratively with the DoL (as the Government's lead agency for the NLTP), and key representatives from the Departments of Health (DoH), Environment Regulation (DER) and Mines and Petroleum (DMP). The DoL-chaired Steering Committee included representatives from these agencies and members from the Northampton Shire council representing the community. The NLTP was designed by the Government to broadly adopt the framework and approaches typically used in assessment of contaminated sites. A DER-accredited Auditor (Peter Beck from GHD) was also engaged to provide an extra level of robustness and confidence to the overall approach and project outcomes. The main objectives of Phase 1 of the NLTP were to: determine those properties which do not have tailings present and need no further consideration in the NLTP; determine those properties which have tailings present and require remediation and/or management in subsequent phases of the NLTP; and present a summary of remediation and management options for properties where tailings were identified to support planning and budgeting for the remediation phase of the project. The main obstacles to achieving these objectives included: community engagement and obtaining consent from land owners; achieving a scientifically robust investigation within budget limitations and using the least intrusive methods possible; elevated naturally occurring background levels of lead and other metals; implementing interim management measures on properties assessed as being at risk during the investigation. (author)