Background
The Department of Water and Environmental Regulation (the department) continues to receive a significant number of odour complaints from the Secret Harbour and Mandurah areas, including Singleton, Lakelands and surrounding suburbs.
Field odour surveys were conducted by officers from the department during 2024 which identified the activities of several companies in Nambeelup as having the potential to cause or contribute to odour emissions in the community.
Three premises in the Nambeelup area hold licences under Part V of the EP Act which specify operating conditions to be met to mitigate emissions, including odours. Information on the licences is publicly available.
- C-Wise () liquid waste and compost manufacturing and soil blending facility.
- CM Farms () intensive piggery, with a licence expiry date of 26 October 2029.
- Mushroom Exchange (), located adjacent to the C-Wise and CM Farms premises, carries out compost manufacturing and soil blending, with a licence expiry date of 27 April 2026.
On 22 February 2024, following departmental investigations, Environmental Protection Notices (EPNs) were issued to two companies in Nambeelup including WA Composts Pty Ltd trading as C-Wise (EPN 202401) and Derby Industries Pty Ltd trading as Craig Mostyn Farms Pty Ltd (CM Farms) (EPN 202402). Non-compliance with the requirements of an EPN is considered a serious offence under the Environmental Protection Act 1986 (EP Act).
View the C-Wise EPN.
View the CM Farms EPN.
The department engaged an odour expert to assist with field odour surveys and investigations of all sites in the Nambeelup precinct. The expert provided independent advice to the department on measures required or necessary to quickly mitigate odour emissions from any identified odour sources.
The department also engaged a wastewater expert to support in the identification of the issues and appropriate solutions.
Current situation
The department acknowledges the impacts on the community from odour and continues to take the issue very seriously.
On 25 October 2024, the department amended C-Wise鈥檚 licence to include new conditions to support better regulation of odour emissions and to require C-Wise to develop a sludge management plan for the storage, treatment and disposal of sludge from the liquid waste ponds on the premises. The objectives of the sludge management plan are to mitigate odour and leachate emissions associated with pond desludging and sludge use and disposal, while ensuring compliance with the per- and poly-fluoroalkyl substances (PFAS) National Environmental Management Plan (NEMP). The licence expiry date is now 22 April 2028.
From the week starting 9 December 2024, for about two weeks, C-Wise will begin maintenance work to remove sludge from two of their operational ponds in a carefully controlled manner. While this process may temporarily increase the risk of odour emissions from the site, it will provide improved operating standards for the future. This is maintenance work that has been reviewed and accepted by the department and is required by their licence.
The department is determining whether further regulatory actions are required to mitigate odour emissions from the Nambeelup premises and to resolve odour issues in the area. Odour issues can take some time to fully address, and the department is continuing to work to reduce any impacts being experienced by the community.
The department is grateful for the community reporting the ongoing odour impacts which greatly assists in the investigation and identification of odour sources.
Community members and residents are reminded that it is important to report odour impacts at the time odour is occurring by calling the Environment Watch Hotline on 1300 784 782 or using the online reporting tool. Please be as specific as you can when describing the odour and the impact it is having on you.
This page will be updated as new information becomes available. If you have any questions relating to this issue, please email info@dwer.wa.gov.au.
