Timber Treaters Bridgetown - Bushfire impacts and recovery

Background

About 4,167 cubic metres of timber treated with copper chrome arsenate (CCA), and approximately 4,219 cubic metres of untreated timber was burnt, releasing ash and smoke particles into the air and leaving large rows of ash on the site. 

CCA is a wood preservative containing copper, chromium and arsenic that is used to protect wood from dry rot, fungi, mould, termites and other pests. 

Site clean-up and remediation 

As a result of the fire, DWER issued a clean-up advisory to Timber Treaters Bridgetown (WA) Pty Ltd (Timber Treaters), to ensure the appropriate recovery and disposal of all CCA contaminated material.  

To perform these works, Timber Treaters engaged an environmental consultant, with the proposed works outlined in an Environmental Management Plan (EMP). A key objective of the EMP was to prevent the release of contaminated materials into the air as dust, and transport over land by surface water runoff, whilst the recovery and containment works were being conducted.  

The Stage 1 clean-up and remediation works relating to the CCA contaminated material, commenced on 14 March 2022, and were completed on April 5, 2022. Throughout the duration of the CCA material related works, dust suppression controls, and real time air monitoring was undertaken. Additional non-CCA related works continued to be conducted after this. 

A DWER officer regularly attended Timber Treaters to ensure the control measures stipulated in the EMP were working effectively in mitigating the potential release of contaminated materials. 

To enable the recovery works to be completed in a timely manner, a temporary containment cell (bunded and lined) was erected at the premises. This on-site temporary containment cell continues to be utilised, until such time as Timber Treaters can fund the final 'Stage 2' off-site disposal works.  

A requirement of all works was to also ensure these works were appropriately validated, with a report to be prepared by the environmental consultant and submitted to DWER for review. 

Licensing activities  

Timber Treaters Bridgetown holds a current environmental licence issued under Division 3, Part V of the Environmental Protection Act 1986 (EP Act) and, despite the recent devastating bushfire, is entitled to continue lawful operations in accordance with the requirements of that licence. 

The licence, L6439/1990/11, regulates emissions and discharges arising from the normal operations of the timber preserving facility and does not extend to regulating emissions arising from unforeseen or extreme events such as the February 2022 bushfire. 

Before issuing the licence, the department considered the risk of impacts to nearby receptors, such as residential properties and communities, from normal and expected operations and infrastructure, and foreseeable equipment and operational failures.  

Following the recent bushfire and given the location and the nature of the timber treatment operations, the department is considering what additional controls may be required to mitigate the risk of such an event occurring in the future. 

The department is aware of community interest in the location and continued operation of Timber Treaters near residential properties, however, it is important to note the provisions of the EP Act do not extend to making decisions on appropriate or compatible land use and zoning. The Timber Treaters’ premises is zoned ‘industrial’ under the Shire of Bridgetown-Greenbushes (Shire) Town Planning Scheme No. 4 (current), therefore, any comments on zoning and compatibility of land use are best addressed to the Shire. 

Contaminated Sites 

The Timber Treaters premises was reported as a suspected contaminated site under the Contaminated Sites Act 2003 (CS Act) on 2 May 2022 following the devastating impacts of the bushfire. A portion of the premises historically used as a railway reserve is already classified under the CS Act as remediated for restricted use.  

Following completion of Stage 1 remediation works, validation sampling was carried out and a report was prepared describing the remediation, validation and ongoing management of residual impacted ash being stored in the temporary containment cell at the site. The report was submitted to the department in late August 2022. We will review the report and use the information in it to inform classification of the site under the CS Act.