Virgin Excavated Natural Material (VENM) Assessment and Classification

Virgin Excavated Natural Material Assessment and Classification

Confluence Environmental undertakes Virgin Excavated Natural Material (VENM) assessments to determine whether excavated natural soil, clay, gravel, sand or rock meets the definition of VENM under NSW waste legislation.

VENM must be natural material excavated from an area that has not been contaminated with manufactured chemicals or process residues as a result of industrial, commercial, mining or agricultural activities. It must also be free of sulfidic ores or soils and other waste.

Assessment therefore involves more than simply confirming that material looks like natural soil.

The source area, site history, surrounding land uses, condition of the material and potential contamination pathways need to be considered to establish whether the VENM definition can be supported.

Where sufficient confidence cannot be established from the available information, targeted investigation and laboratory analysis may be required.

VENM Assessment Approach

The assessment scope is developed around the source site and the material proposed for excavation or movement.

Depending on the project, our assessment can include:

• review of current and historical land use;

• review of previous environmental, geotechnical or contamination reports;

• assessment of surrounding potentially contaminating activities;

• site inspection and visual assessment of the source material;

• review of excavation depth, extent and estimated material volume;

• consideration of fill, waste or anthropogenic inclusions;

• assessment of potential acid sulfate soil or sulfidic soil conditions;

• consideration of naturally occurring asbestos where relevant; and

• targeted soil sampling and laboratory analysis where required.

The objective is to determine whether there is sufficient evidence to support classification of the material as Virgin Excavated Natural Material.

Site History and Source Assessment

VENM classification is fundamentally linked to the origin of the material.

The NSW EPA requires generators to consider both past and present activities at the source site as well as relevant surrounding land uses that could have resulted in contamination. Potential off-site sources, including contaminated groundwater or deposition from surrounding industrial activities, may also need to be considered.

For this reason, material should not be classified as VENM solely because it appears visually clean or geologically natural.

Sites with a history of industrial activity, workshops, fuel storage, agriculture, waste disposal, imported fill or other potentially contaminating activities may require additional assessment before a VENM determination can be made.

When Is VENM Soil Testing Required?

Laboratory testing is not automatically required for every VENM assessment.

The NSW EPA states that chemical testing is not mandatory where sufficient certainty exists that all aspects of the VENM definition are satisfied. However, testing may be required where the available information is insufficient to establish that the material is free from relevant contamination, sulfidic soils or other disqualifying conditions.

Where sampling is required, the investigation is developed from the site history, potential contamination sources, material volume and characteristics of the excavation area.

Depending on the site, analysis may include:

• metals;

• petroleum hydrocarbons;

• PAHs;

• pesticides;

• asbestos;

• acid sulfate soil parameters; or

• other contaminants associated with identified historical activities.

The analytical program should respond to the credible contamination risks associated with the source site, rather than applying a standard laboratory suite to every project.

VENM Reports and Certificates

Following assessment, Confluence Environmental can prepare a VENM report or supporting VENM certificate documenting the source material, assessment undertaken and basis for the VENM determination.

Documentation may include:

• identification of the source site;

• description of the material and excavation area;

• relevant site history;

• findings of the site inspection;

• sampling and laboratory results where undertaken;

• assessment against the VENM definition; and

• the basis for the final classification.

A VENM certificate is not legally mandatory under the NSW framework. The EPA provides the certificate as a means of giving generators, contractors and receiving sites confidence that the relevant VENM requirements have been considered. It may be completed by the waste generator or by a consultant acting on their behalf.

Project specifications, contractors, receiving sites or development requirements may nevertheless request supporting VENM documentation before accepting material.

What Does Not Qualify as VENM?

Material cannot be classified as VENM simply because it consists predominantly of soil or rock.

Potential reasons material may not satisfy the definition include:

• contamination from industrial, commercial, mining or agricultural activities;

• manufactured chemicals or process residues;

• sulfidic ores or soils;

• other waste within the material;

• processed or mixed material;

• anthropogenic inclusions;

• naturally occurring asbestos where relevant; or

• insufficient information to establish that the VENM definition has been met.

The NSW EPA also states that material containing detectable reduced inorganic sulfur above the laboratory reporting limit would be considered to contain sulfidic ores or soils and therefore would not satisfy the VENM definition.

The assessment should therefore identify potential disqualifying conditions early, particularly where large volumes of material are proposed to be excavated or transported.

What Happens if Soil Does Not Qualify as VENM?

Material that cannot be classified as VENM may still have other lawful management or reuse pathways.

Depending on the material and project, this may include assessment under the Excavated Natural Material Order and Exemption, broader waste classification or disposal to an appropriately authorised facility.

The NSW EPA currently maintains the Excavated Natural Material Order and Exemption 2014 as part of its resource recovery framework.

Confluence Environmental can assess the available information and advise whether the material should progress to:

• ENM assessment;

• waste classification;

• additional sampling;

• contaminated soil assessment; or

• another appropriate management pathway.

This allows the project to move into the correct classification process rather than attempting to force material into a VENM classification that cannot be supported.

VENM and Waste Classification

VENM sits within the broader NSW waste and resource recovery framework.

Where VENM is a waste, the NSW EPA identifies it as pre-classified general solid waste (non-putrescible). EPA NSW

This is different from saying that VENM is simply “not waste”.

Correct classification remains important because the source, destination and circumstances in which excavated material is transported or reused can affect the applicable regulatory requirements.

Where VENM cannot be demonstrated, a soil waste classification or assessment against another resource recovery pathway may be required.

Clear, Defensible Outcomes

A VENM assessment should provide more than a laboratory certificate.

Our assessments bring together the site history, source conditions, field observations and analytical data where required to establish a clear basis for the material classification.

Depending on the findings, the assessment may determine that:

• the material meets the VENM definition;

• further targeted assessment is required;

• the material should be assessed as ENM;

• broader waste classification is required; or

• another material management pathway should be considered.

The objective is to provide the project team, contractor and receiving site with a clear and defensible basis for managing the excavated material.

Integrated with Excavation, Development and Construction

VENM assessment is most useful when undertaken before large-scale excavation or off-site movement begins.

We consider the proposed excavation area, material volumes, construction program, existing site information and intended material destination when developing the assessment scope.

This allows sampling, reporting and material-management requirements to be considered before excavation rather than after stockpiles have already been generated.

VENM assessment can also be integrated with:

• Preliminary Site Investigations;

• Detailed Site Investigations;

• waste classification;

• ENM assessment;

• acid sulfate soil assessment;

• asbestos in soil assessment; and

• construction environmental management.

VENM Assessment Across NSW

Confluence Environmental provides VENM assessment, VENM classification and VENM reporting services across Newcastle and the Hunter, Lake Macquarie, Maitland, the Central Coast, Sydney and Greater Sydney, the Mid Coast, Mid North Coast and regional NSW.

Our assessments support civil contractors, developers, infrastructure projects, builders and project teams requiring clear advice on the classification and management of excavated natural material.