What Is ENM? Excavated Natural Material, ENM Soil Classification and the ENM Order
Excavated Natural Material (ENM) is a specific resource recovery material in NSW that allows certain excavated natural soil and rock to be reused as engineering fill or in earthworks when the requirements of the NSW EPA Excavated Natural Material Order and Exemption are satisfied.
ENM commonly becomes relevant where soil generated during excavation does not meet the definition of Virgin Excavated Natural Material (VENM) but may still be suitable for lawful reuse under the NSW resource recovery framework.
However, ENM is not simply another term for clean soil.
The source and composition of the material must satisfy the ENM definition, prescribed sampling and laboratory testing must be completed, relevant chemical and physical criteria must be met, and the documentation requirements of the ENM Order must be followed before the material is supplied under the exemption.
What Is ENM?
Under the Excavated Natural Material Order 2014, ENM is naturally occurring rock and soil that has been excavated from the ground, contains at least 98% natural material by weight, and does not meet the statutory definition of Virgin Excavated Natural Material.
Examples of potentially suitable ENM material may include naturally occurring sandstone, shale, clay and soil.
Importantly, the ENM Order excludes material that is located within a defined hotspot, has been processed, or contains asbestos, Acid Sulfate Soils, Potential Acid Sulfate Soils or sulfidic ores.
This means that excavated material cannot be called ENM simply because most of it appears to be natural soil.
It must meet the definition and satisfy the requirements of the Order.
What Is the ENM Order?
The Excavated Natural Material Order 2014, commonly called the ENM Order, establishes the requirements that apply to generators supplying excavated natural material for land application under the corresponding resource recovery exemption.
As of October 2026, the NSW EPA continues to list the Excavated Natural Material Order and Exemption 2014 as current resource recovery instruments.
The Order establishes requirements relating to material definition, sampling, laboratory analysis, chemical concentrations, physical characteristics, notification and record keeping.
A project therefore does not obtain an individual EPA approval every time ENM is generated. The general Order and Exemption can be relied upon where all applicable conditions are met. The EPA also notes that other requirements, including development consent where necessary and permission from the owner and occupier of the receiving land, may still apply.
What Is the ENM Exemption?
The Excavated Natural Material Exemption 2014 operates alongside the Order.
Broadly, the Order places requirements on the generator or supplier, while the Exemption establishes conditions applying to the consumer receiving and applying the ENM to land.
Under the current Exemption, compliant ENM can only be applied to land as engineering fill or for use in earthworks. The consumer also has record-keeping obligations and must ensure the material meets the applicable requirements when received.
For that reason, references to an “ENM exemption order” are usually referring to two separate but related instruments:
the Excavated Natural Material Order 2014 and the Excavated Natural Material Exemption 2014.
When Might Soil Be Assessed as ENM?
An ENM soil classification may be considered where excavated natural material does not satisfy the VENM definition but is otherwise potentially suitable for reuse under the ENM resource recovery framework.
This can occur during bulk excavation, subdivision works, road and civil works, service trenching, basements, residential and commercial development, infrastructure construction and other earthworks.
The appropriate classification should be considered before assuming that excavated material can be transported to another site for reuse.
If the material satisfies the VENM definition, VENM may instead be the appropriate pathway.
If it cannot meet the ENM requirements, another waste classification or management pathway may be required.
Does ENM Require Soil Testing?
Yes. Unlike VENM, the ENM Order contains prescribed sampling and testing requirements for material being supplied under the Order.
Before supplying ENM, the generator must prepare a written sampling plan and undertake the required sampling and analysis.
The testing requirements address metals, electrical conductivity, pH, PAHs, benzo(a)pyrene, BTEX, petroleum hydrocarbons and specified foreign materials. Testing required under the Order must be undertaken by a NATA-accredited laboratory, or equivalent.
The results are then assessed against both the maximum average concentrations and absolute maximum concentrations specified in the Order.
This is an important distinction between ENM soil classification and a general contaminated-land investigation. The ENM assessment is being undertaken for a specific resource recovery pathway with prescribed requirements.
How Is ENM Sampling Undertaken?
The sampling requirements depend on whether the ENM material is still in situ or has already been excavated and stockpiled.
For stockpiled material, the ENM Order specifies a minimum number of samples according to the quantity of material. For example, a stockpile of less than 500 tonnes requires three samples, with the required number increasing as stockpile size increases. Stockpiles greater than 4,000 tonnes require the sampling regime to be repeated.
For in-situ ENM soil, the Order uses systematic surface sampling based on the area being assessed. It also requires sampling at depth where the excavation extends to 1.0 metre below ground level or deeper, together with additional sampling where staining, odour, discolouration or other potential contamination indicators are observed.
This is why it is generally preferable to consider ENM requirements before excavation begins.
Characterising material in situ can allow the excavation footprint and depth to be assessed systematically and may make it easier to identify and segregate unsuitable areas before different materials are mixed in a stockpile.
What Does ENM Soil Get Tested For?
The current ENM Order contains prescribed criteria for a range of chemical and physical attributes.
These include:
mercury, cadmium, lead, arsenic, chromium, copper, nickel and zinc;
electrical conductivity and pH;
PAHs and benzo(a)pyrene;
benzene, toluene, ethylbenzene and xylenes;
petroleum hydrocarbons; and
specified foreign materials including rubber, plastic, bitumen, paper, cloth, paint and wood.
The Order establishes both average and absolute criteria for these parameters.
An ENM assessment should therefore consider the material as a whole rather than relying on a single laboratory result to describe a large excavation.
Can ENM Contain Some Foreign Material?
ENM must contain at least 98% naturally occurring material by weight, but that does not mean any remaining material is automatically acceptable.
The ENM Order contains specific limits for rubber, plastic, bitumen, paper, cloth, paint and wood, while other exclusions continue to apply.
Material containing asbestos, for example, is expressly excluded from the ENM definition.
The presence of demolition waste, significant anthropogenic material or other unexpected inclusions should therefore be investigated rather than assuming the “98% natural material” provision automatically makes the soil ENM.
Can ENM Contain Asbestos?
No.
The current Excavated Natural Material Order expressly excludes material containing asbestos from the definition of ENM.
Where asbestos-containing material, asbestos fines or another credible asbestos source is identified, the material should be assessed and managed under the appropriate asbestos and waste framework rather than supplied as ENM.
Can Acid Sulfate Soil Be ENM?
The ENM Order also excludes Acid Sulfate Soils, Potential Acid Sulfate Soils and sulfidic ores from the ENM definition. EPA NSW
Acid sulfate soil conditions therefore need to be considered where relevant to the excavation area, particularly in coastal and low-lying environments.
The Order itself also contains specific requirements for assessment where acid sulfate soils may be present.
What Is an ENM Hotspot?
The ENM Order includes the concept of a hotspot.
For in-situ material, additional samples are required where observations such as staining, odours or discolouration indicate possible contamination. Identified hotspots are required to be segregated and excluded from the material proposed for reuse as ENM.
This is an important reason why field observations remain relevant even where a systematic ENM sampling program has been completed.
Laboratory analysis and field assessment work together to determine whether the material proposed for supply is compliant.
What Is an ENM Certificate?
The terminology can be confusing because clients sometimes request an “ENM certificate.”
The ENM Order does not simply require a generic certificate issued by an environmental consultant.
Instead, before each relevant transaction, the generator must provide the recipient with a written statement of compliance certifying that the requirements of the Order have been met, together with a copy of or link to the applicable Order and Exemption.
An environmental consultant may prepare an ENM assessment or classification report documenting the investigation, sampling, laboratory results and basis for determining whether the material complies with the Order.
That supporting technical report is distinct from the generator's statutory documentation obligations under the Order.
What Does an ENM Assessment Report Include?
An ENM report would typically document the source site and excavation area, material proposed for reuse, applicable sampling plan, field methodology, sampling locations and depths, laboratory analytical results, assessment against the requirements of the ENM Order and the resulting material-management conclusions.
Where an area or material does not satisfy the requirements, the report should identify that limitation and provide recommendations for segregation, further assessment or another waste management pathway.
The objective is not simply to produce a laboratory certificate. It is to establish a defensible connection between the material assessed, the sampling undertaken and the ENM material proposed to be supplied.
What Happens if ENM Exceeds the Criteria?
Material that does not comply with the requirements of the ENM Order cannot simply be supplied under that Order and Exemption.
Depending on the reason for non-compliance, the next step may involve segregation of an identified hotspot, further investigation, assessment under another resource recovery pathway or waste classification for lawful disposal.
This is why ENM should be considered a specific reuse pathway rather than a generic waste classification.
A material may be relatively low in contamination but still fail to satisfy one of the ENM requirements.
ENM vs VENM
VENM and ENM are related but separate pathways.
VENM is a statutory definition for qualifying virgin excavated natural material.
ENM applies to certain naturally occurring excavated rock and soil that does not meet the VENM definition but satisfies the definition and conditions of the ENM Order and Exemption.
ENM generally involves prescribed sampling and laboratory assessment under the Order, whereas chemical testing is not automatically mandatory when determining whether material satisfies the VENM definition.
For a detailed comparison, see VENM vs ENM NSW | What Is the Difference? — Confluence Environmental
Can ENM Be Reused Anywhere?
No.
The ENM Exemption applies to the use of compliant excavated natural material as engineering fill or in earthworks and contains conditions applying to the receiving site and consumer.
Use of an EPA resource recovery Order and Exemption also does not remove the need to comply with other relevant requirements.
The EPA states that development consent may still be necessary and that permission from the owner and occupier of the land where the recovered material will be used is required.
The intended destination should therefore be considered as part of material-management planning rather than assuming compliant ENM can be deposited on any property.
What Records Are Required for ENM?
Record keeping is an important part of the ENM framework.
The Order requires generators to retain specified records for six years, including the sampling plan, characterisation results, identified hotspot information, quantity of ENM supplied and details of recipients.
The corresponding Exemption also imposes record-keeping requirements on consumers receiving the material.
This reinforces why material classification, transport and receiving-site documentation should be coordinated rather than treated as separate activities.
When Should ENM Classification Be Completed?
Where possible, ENM assessment should be planned before bulk excavation begins.
Early assessment allows the sampling design to respond to the actual excavation footprint and depth and enables unsuitable material or hotspots to be identified before soil from different areas becomes mixed.
This can be particularly important for subdivisions, basement excavations, civil infrastructure, service trenches and other projects generating substantial volumes of excavated soil.
Where material has already been excavated, stockpile assessment can still be undertaken in accordance with the applicable ENM requirements.
Frequently Asked Questions (FAQ):
Q: What does ENM stand for?
ENM stands for Excavated Natural Material. In NSW, it is defined under the Excavated Natural Material Order 2014 for the purposes of the resource recovery framework.
Q: What is ENM soil?
ENM soil is naturally occurring excavated soil or rock that satisfies the definition and requirements of the ENM Order, including the requirement for at least 98% natural material by weight and compliance with applicable sampling, chemical and material criteria.
Q: Does ENM require testing?
Yes. The ENM Order contains prescribed sampling and laboratory testing requirements that must be met before material is supplied under the Order.
Q: Is ENM the same as VENM?
No. ENM specifically includes qualifying natural rock and soil that does not meet the definition of VENM and satisfies the ENM Order requirements.
Q: Can ENM contain asbestos?
No. Material containing asbestos is excluded from the ENM definition under the current Order.
Q: Can acid sulfate soil be ENM?
No. Acid Sulfate Soils, Potential Acid Sulfate Soils and sulfidic ores are excluded from the ENM definition.
Q: Is there an ENM certificate?
The ENM Order requires the generator to provide a written statement of compliance to the recipient. An environmental consultant may separately prepare an ENM assessment or classification report supporting the determination.
Q: What happens if soil does not meet ENM requirements?
It cannot be supplied under the ENM Order and Exemption. Depending on the circumstances, the material may require segregation, further assessment, another resource recovery pathway or waste classification.
ENM Soil Classification and Assessment in NSW
Confluence Environmental provides ENM assessment, ENM soil classification and Excavated Natural Material testing across NSW for civil works, development, infrastructure and earthworks projects.
Our environmental consultants can develop the sampling plan, undertake in-situ or stockpile sampling, coordinate NATA-accredited laboratory analysis and assess the results against the applicable requirements of the Excavated Natural Material Order.
Where material cannot be supported as ENM, we can also advise on VENM, alternative resource recovery pathways and soil waste classification to establish the appropriate next step.