Chain of Custody (CoC)

Summary

A chain of custody (CoC) is the documented trail tracking the collection, handling, transport and analysis of samples from field to laboratory, ensuring sample integrity, defensibility and compliance. In Australia’s environmental consulting, remediation and compliance context, maintaining a robust Chain of Custody is essential for regulatory reporting, due diligence and audit readiness.

Definition

A chain of custody (CoC) is a structured, chronological record of the custody, control, transfer, analysis and disposition of environmental samples or materials (e.g., soil, groundwater, vapour, air) that provides traceability, accountability and evidence that the sample analysed is the one collected in the field

Why It Matters

In the Australian environmental consulting, land remediation and regulatory compliance environment, the importance of a robust Chain of Custody cannot be overstated:

• Data integrity and defensibility: For investigations (such as those under the National Environment Protection (Assessment of Site Contamination) Measure 2013 (NEPM) or state-based contaminated-land frameworks), regulators require that results be traceable back to the original samples. If custody is broken, the analysis may be rejected or deemed non-compliant.

• Audit and legal accountability: Should contamination litigation, enforcement action, or due-diligence review arise, the CoC forms a critical link proving that samples were handled correctly and results are reliable.

• Quality assurance/quality control (QA/QC): Laboratories and consultants recognise that a properly completed CoC helps ensure correct sample labelling, preservation, holding times and chain breaks are documented.

• Project approvals and compliance: Many development consents, remediation plans and licence conditions include requirements for validated sampling programmes. The Chain of Custody supports the whole sampling programme (for example, soil & waste classification, groundwater sampling, vapour intrusion assessments) and links field work to laboratory results and reporting.

• Stakeholder confidence: Developers, remediation managers, regulators and insurers rely on trustworthy data. Demonstrating a clear CoC enhances credibility when presenting reports such as a Validation Report, Remediation Action Plan or ESA.

When It’s Required

Common triggers

• Environmental Site Assessments (ESA/DSI): Sample collection of soil, groundwater, vapour, air or other media for contamination investigation.

• Remediation and validation activities: During excavation, fill removal, groundwater extraction or decommissioning—samples from the site must be tracked via CoC to support final reporting and closure.

• Waste classification and disposal: Soil, excavated natural material (ENM), hazardous waste or imported fill must often be characterised via laboratory testing. The CoC ensures materials transported and analysed are aligned with project records.

• Regulated monitoring programmes: Monthly or periodic sampling (e.g., groundwater monitoring wells, dust compliance) under licence or consent conditions must show chain continuity for regulatory validity.

• Legal or insurance-driven investigations: If samples may underpin liability or insurance claims, the CoC becomes essential for defensibility.
  

Regulatory & guidance context

While CoC is not always explicitly defined in individual state legislation, Australian laboratories and environmental consultants recognise its role in accordance with best practice sampling design and analysis guidelines.

For example:

• The NSW Environment Protection Authority’s “Sampling Design Part 1 – Application” references the importance of traceable sampling and documentation.

• Environmental laboratories require a CoC or sample submission form before analysis can proceed.

• Laboratory resources emphasise that "Quality reporting starts at the beginning with the collection of samples and a properly completed Chain of Custody (COC) form".

How We Can Help

At Nova Group Pacific, our environmental consulting capabilities include full Chain of Custody management integrated into our broader services—ensuring your sampling programmes are defensible, compliant and aligned with your project objectives.

Our support includes:

• Designing and implementing sampling protocols that incorporate CoC forms consistent with laboratory and regulatory requirements.

• On-site supervision of sample collection, documentation of individuals responsible, transport conditions, labelling, preservation and chain transfers from field to lab.

• Preparation and review of CoC documentation alongside other deliverables such as:
  
  • Soil & Waste Classification
  • Groundwater Sampling programmes
  • Remediation Action Plans (RAPs)
  • Validation Reports
    

• Liaising with NATA-accredited laboratories to ensure chain continuation, correct sample handling, preservation, holding time compliance and that analytical data remains traceable.

• Integrating CoC records with your compliance reporting system, enabling smoother regulatory submission and audit readiness.

Contact our experts to ensure your sampling programme and its Chain of Custody is rigorous, defensible and supports your compliance, remediation or redevelopment objectives.

Related Terms and Concepts

• Groundwater Sampling – The collection of groundwater samples often requires strict chain-of-custody procedures.

• Soil & Waste Classification – Excavated materials tested for reuse or disposal must often have CoCs to demonstrate the source, transport and analysis legitimacy.

• Validation Report – A report verifying remedial works may rely on analytical data underpinned by correct CoC procedures.

• Environmental Site Assessment (ESA) – Initial investigations that collect samples whose integrity must be maintained via CoC.

• Hazardous Waste – Management and disposal of hazardous materials often require traceable sampling and analysis supported by CoC for legal and regulatory certainty.