The Broken Hill Environmental Lead Study (BHELS) was commissioned by the NSW Environment Protection Authority (EPA) in 2016 to inform remediation efforts underway as part of the Broken Hill Environmental Lead Program (BHELP) to address lead contamination and exposures.
The department was engaged to develop and deliver this 4-year study, in collaboration with the EPA and Macquarie University. The BHELP Steering Committee has endorsed the study as a high-priority project.
Study findings will help direct future efforts to reduce community lead exposure in Broken Hill.
What are the aims of the study?
The study aims to monitor airborne and deposited lead and assess contributions of current emissions from Line of Lode mining leases and emissions from areas affected by historic emissions ('legacy lead').
Specific study objectives are to:
- determine likely source areas contributing to airborne lead levels in Broken Hill based on a year of wind-directional measurements of ambient air lead at selected locations, and analysis to identify the location of sources contributing to airborne lead
- monitoring of airborne and deposited lead levels for a further 2 years to evaluate the effectiveness of remediation works in reducing lead levels.
What sampling and analysis is being undertaken?
Wind-directional high volume air samplers were deployed at 5 sites representative of community exposures; 3 sites in North Broken Hill and 2 sites in South Broken Hill. Samples were sent to a laboratory accredited by the National Association of Testing Authorities (NATA) for gravimetric analysis to determine the total suspended particles (TSP) mass and the associated lead content.
Dust deposition gauges were installed at the sampling sites to provide information on total dust deposition and deposited lead levels.
Ambient particulate matter concentrations were continuously measured at 2 sites using DustTrak Aerosol Monitors (DustTraks) to provide more time-resolved information on variations in particle concentrations in Broken Hill. Meteorological data from the Australian Bureau of Meteorology's Automatic Weather Station at Broken Hill Airport were used in the study.
Macquarie University undertook a pilot study to investigate the usefulness of microscopy techniques to characterise the morphology and chemistry of airborne particles collected at Broken Hill for source attribution purposes.
What are the key findings of the study?
The Broken Hill Environmental Lead Study is now available on the LeadSmart Broken Hill page.
Based on the study findings, the recommendation was to set up a monitoring network compliant with Ambient Air Quality National Environment Protection Measure (AAQ NEPM) to assess community exposure and allow for comparison with health standards for lead. This work continues as part of the Broken Hill Environment Lead Study.