Former ChlorAlkali Plant Remediation Project Overview
Orica has safely remediated mercury contaminated soil at the site of the Former ChlorAlkali Plant (FCAP) at the Botany Industrial Park. The areas which have been remediated are shown as Blocks A, M and G in the figure below.
A detailed Human Health and Environmental Risk Assessment (HHERA) was prepared to assess the potential risks to human health and the environment associated with mercury in soil and groundwater. The full report can be viewed here.
Results of Orica’s groundwater mercury monitoring are also available here.
Fact sheets on the FCAP Remediation Project can be found here.
Remediation works are compliant with the EPA's Management Order.
Orica has excavated mercury contaminated materials at Blocks A and M, validated the excavation surfaces against the remediation criterion agreed with the NSW EPA, and backfilled the excavations with soil that met the same remediation criterion (Stage 1). Block G remediation involved the construction of a purpose built cut-off wall and vapour barrier to isolate on-site mercury from surrounding groundwater and to prevent mercury vapour emissions (Stage 4).
In addition to the on-site containment approach, the NSW EPA required the targeted removal of mercury and mercury contaminated materials on Block G, to the extent practicable (Stage 2), prior to installation of the on-site containment system. Recovered elemental mercury has been sent off site for recycling and mercury contaminated materials from all excavations have been chemically treated and disposed of off site.
The timeframe for when each stage of the Former ChlorAlkali Plant mercury remediation project was conducted is outlined below.
Project updates were provided at meetings of the Orica Botany Liaison Committee.
- Blocks A & M excavation and reinstatement
|Aug - Nov 2013
- Block G targeted excavation and reinstatement
|Sep - Dec 2013
- Decontamination and site preparation and removal of Temporary Emissions Control Enclosure (TECE) and associated Emissions Control Systems (ECSs)
|Jan - Nov 2014
- Construction of cut-off wall
- Installation of capping system
|Feb 2015 - July 2016
| Block G Remediation Validation Report
||Submitted to EPA December 2016
| Long-Term Site Environmental Management Plan
||Submitted to EPA January 2017