Healthy Environment, Healthy Community, Healthy Business

Environment Protection Authority

EPA update on work to manage odours at WestConnex St Peters

Media release: 23 June 2017

The NSW Environment Protection Authority (EPA) is continuing to take action to manage odours emitted from the WestConnex St Peters Interchange site, recently issuing a Clean Up notice to the contractors and monitoring the installation of a new treatment plant.     

The EPA issued a Clean Up notice to  CPB Contractors, on 16 June 2017. That notice, which is published on the EPA’s Public Register, requires the company to lower the level of leachate in the area of excavation works before further works are undertaken. The odours are linked to leachate – that is, liquid that has run through the old landfill that has been unearthed as works progress at the St Peters site. The odours occur when that liquid pools and as such the odours are worse when the site is hit with wet weather.

As a result of the EPA’s actions the company stopped works on the site until the leachate level was lowered to a level that reduces the odours.

The company has also installed a second leachate treatment plant. This plant is designed to lower the leachate level. This plant is being finalised and commissioned today (June 23), and is expected to be operational by midnight. 

These latest actions are in addition to a number of previous actions the EPA has taken to address the odours and respond to the community’s concerns.

On 28 March 2017, the EPA issued a Prevention Notice to the company, specifying actions it must implement to eliminate offensive odours coming from the Premises. These actions have since been incorporated into the company’s Environment Protection Licence. This includes a requirement to undertake all reasonable and feasible measures to prevent leachate from pooling and to cover or remove pooled leachate as soon as practicable. 

The licence also requires independent odour and gas monitoring to be undertaken around the perimeter of the site and at St Peters school on a daily basis.

EPA Regional Director Metropolitan Giselle Howard said the EPA would continue to undertake regular inspections to determine compliance and effectiveness of the required actions

“The EPA is concerned about the unacceptable impacts on the local community and will continue to take action to minimise the odours,” Ms Howard said.

“We encourage residents to contact the Environment Line on 131 555to report offensive odour. The EPA will respond to any reports .”

EPA fines WestConnex contractor for Cooks River pollution

The EPA has fined CPB Contractors Pty Ltd $15,000 for discharging untreated groundwater to the Cooks River at its Arncliffe site in November.  

On 2 November 2016, untreated groundwater was discharged from the Arncliffe worksite to the Cooks River causing an orange-brown plume that stretched nearly 200m long and up to 10m wide.

CPB Contractors pumped the groundwater from an onsite excavation, despite being aware that it contained elevated levels of metals including iron, zinc and manganese. It is a condition of CPB Contractors’ environment protection licence  that water is only able to be discharged from the site after it meets stringent requirements. .

To comply with these licence conditions, CPB Contractors has installed a new groundwater treatment plant at the site. However, on the day of the untreated discharge, CPB did not use the existing treatment plant on site, due to operating problems. CPB did not undertake some of the required water quality tests before discharging the groundwater.

Water samples from the EPA’s investigation revealed that areas of the river had levels of iron, zinc and manganese that were higher than upstream levels, and were above national standards for acceptable water quality.

Penalty notices are one of a number of tools the EPA can use to achieve environmental compliance including formal warnings, official cautions, licence conditions, notices and directions and prosecutions. For more information about the EPA’s regulatory tools, see the EPA Compliance Policy at


Contact: EPA Public Affairs

Page last updated: 23 June 2017