Stage 1 Works (2009–2010):
To achieve the objectives, EESI implemented a comprehensive work program, including the extension of the existing groundwater monitoring network through the installation of 9 new monitoring bores. This facilitated additional groundwater sampling, further delineating the vertical and lateral extent of contamination and assessing migration pathways. Soil assessment involved test pitting at 22 locations, analysing soil samples collected from test pits and during groundwater well installation for chemicals of concern. The analysis of groundwater from the new monitoring bores and collation of the data into a detailed report provided insights into the contamination status and laid the groundwork for future stages of work.
Stage 2 Works (2017–2019):
In subsequent years (2017–2019), EESI was contracted again to provide higher-level contamination consulting services. This involved a detailed review of existing soil, groundwater, and subsurface landfill gas data. A data gap assessment and revised Contaminant Source Model (CSM) and qualitative risk assessment (QRA) were prepared. A site inspection assessed the condition of the well network, and a groundwater gauging assessment was conducted. The culmination of these efforts resulted in the preparation of a Remediation Options Assessment (ROA) to inform the Council of potential future site use(s) based on existing liabilities and contamination status.
Through EESI's expertise, the former Lithgow Gasworks site underwent comprehensive assessments, providing the Council with valuable insights into contamination status, liabilities, and potential future uses. The extended groundwater monitoring network and detailed soil assessments established a robust foundation for informed decision-making. The Remediation Options Assessment (ROA) empowered the Council with actionable recommendations, facilitating effective planning for the site's future, considering both existing liabilities and contamination status.