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Dense forest with bare trees and scattered fallen logs in a swampy area.Dense forest with bare trees and scattered fallen logs in a swampy area.

Deanmill Timbermill Mandatory Audit

Mandatory Audit under the Contaminated Sites Act of a timber mill historically using arsenic

Client

Confidential Client 

Location

Confidential Location

Connect with an expert

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Ivan Kwan BEng
Principal Environmental Engineer

Strategic Contaminated Sites Auditing and Collaboration 

We took a strategic view to auditing to distill the information and optimize client needs. We worked with the end goal in mind in relation to land use, assessing opportunities and constraints within the clients' objectives. Closely working with the consultant and the client, we ensured alignment within the project team to achieve the site's suitability objective. The first phase was to reclassify land that had been inadvertently reported to the regulator as impacted following a strategic assessment. Then the approach was to focus on offsite impacts while managing onsite contamination to workers.  

Strategic Site Reclassification  

By reclassifying land that had been inadvertently reported as impacted, this allowed the consultant to focus effort on the areas that were contaminated. As the Auditor, we were able to recommend the successful reclassification of a large portion of the site. 

Stakeholder Engagement Support  

CDM Smith maintained a close working relationship and supported the client with communications to the regulators and downstream landowners who may be impacted assisting with the language and conveying key messages.  

Health Risk Assessment Review and Support  

CDM Smith’s team of health risk assessors supported the review and audit of the consultant's assessment. We were able to dissect the exposure pathway with an assessment of bioavailable against bio-accessible arsenic to understand risk. 

Complex Hydrogeology  

The interactions among groundwater, surface water, and topography were complex, influencing the migration of contaminants. CDM Smith conducted a comprehensive review of the conceptual site model to analyse pathways to potential contaminant receptors. 

The Mandatory Audit supported informed decision-making around the future use of the Deanmill Timbermill site while meeting regulatory obligations under the Contaminated Sites Act. By taking a strategic, outcomes-focused approach, CDM Smith helped reduce unnecessary regulatory burden, clarified risk pathways, and ensured that remediation and management efforts were proportionate to actual site conditions. The audit outcomes provided regulators, the client, and stakeholders with confidence that contamination risks were appropriately understood, managed, and communicated. This approach enabled practical site management solutions that balanced worker safety, environmental protection, and long-term land use objectives, while supporting regulatory compliance in a complex contaminated land setting.

Meet our Expert!

Connect with an expert to find out how we delivered this project. 

Person in a blue suit, pink shirt, and tie stands by a window with a modern building backdrop.

Ivan Kwan

Principal Environmental Engineer

Ivan Kwan is a Principal Environmental Engineer and accredited contaminated sites auditor with 25+ years’ experience in water and environmental risk.

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