Hazardous vs Non-Hazardous Waste: What Procurement Teams Should Know

When procuring waste management services, a fundamental question is also one of the easiest to overlook: Is the waste hazardous or non-hazardous? The answer influences far more than the price of collection.

This post is part of our series supporting procurement teams. Our previous post in this series is worth a read. You can find it here.

Waste classification can determine how material should be stored, the documentation required, who can transport it, where it can be taken and which treatment, recovery or disposal options are available.

For procurement teams, understanding the fundamentals of waste classification can therefore lead to better tender specifications, more meaningful supplier comparisons and fewer unexpected costs once a contract is underway.

You don’t need to become a waste classification specialist.
But understanding the right questions to ask can make a significant difference.

Why Waste Classification Matters

As we discussed in the previous post, under the Environmental Protection Act 1990, businesses have a legal Duty of Care over the waste they produce or control.

Current Environment Agency guidance requires businesses to classify their waste before it is collected, disposed of or recovered. The classification helps establish whether the waste is hazardous, how it should be handled, which organisations are authorised to receive it and what information needs to appear on the accompanying documentation, and for procurement teams, that creates an important principle:

Waste should be properly understood before a management route is selected or compared on price.

If suppliers are working from incomplete or inconsistent information, apparently comparable quotations may not actually be offering the same solution.

Hazardous and Non-Hazardous Waste: What’s the Difference?

Hazardous waste contains substances or possesses properties that mean it requires additional controls to protect people and the environment. Depending on its composition, these properties can include characteristics such as flammability, corrosivity, toxicity and carcinogenicity.

Non-hazardous waste does not meet the criteria for classification as hazardous, but that doesn’t mean it can be managed without appropriate controls.

For organisations operating in manufacturing, food and beverage production, chemicals, utilities, engineering and other industrial sectors, relevant waste streams can include:

• Hazardous sludges
• Non-hazardous sludges
• Hazardous liquid waste
• Non-hazardous liquid waste
• Process waters
• Tank and interceptor residues
• Wash waters
• Oils and oily residues
• Packaged chemicals
• Out-of-specification products
• Cleaning and maintenance wastes

Two waste streams that appear similar can potentially require very different management routes depending on their origin and composition. That’s why visual appearance alone isn’t enough to determine how a waste should be managed.

Who Is Responsible for Classifying Waste?

This is particularly important for procurement teams. A common misconception is that once a waste contractor has been appointed, responsibility for understanding the waste simply passes to the contractor.

Businesses producing waste retain responsibilities under the waste Duty of Care, including providing an accurate description when waste is transferred.

The Environment Agency states that businesses must classify the waste they produce before it is collected, disposed of or recovered.

That doesn’t mean procurement managers needs to become experts in waste chemistry. Instead, organisations should have appropriate processes for identifying, characterising and classifying their waste and for supplying contractors with sufficient information to determine how it can be safely and compliantly managed.

An experienced environmental waste management partner can support this process, identify gaps in the available information and advise when further assessment may be required.

What Is WM3?

Anyone regularly involved in hazardous waste procurement is likely to encounter the term WM3.

WM3 is the technical guidance produced by the UK environmental regulators for the classification and assessment of waste. You can learn more directly here, or from our previous post for procurement teams here.

In practical terms, waste classification can require information about:

• Where the waste originated
• The process that generated it
• The substances likely to be presentIts chemical composition
• Concentrations of relevant substances
• Applicable hazardous properties
• The appropriate List of Waste code

For relatively straightforward waste streams, information about the manufacturing process, raw materials and products involved may provide much of what’s required.

For more complex or variable wastes, further investigation or chemical analysis may be necessary.

This is one reason communication between operational, environmental, technical and procurement teams is so important when putting waste services out to tender.

Understanding EWC and List of Waste Codes

Waste descriptions are assigned classification codes commonly referred to as List of Waste (LoW) codes or European Waste Catalogue (EWC) codes.

These codes help identify waste according to its source and type.

However, choosing the correct code isn’t always as straightforward as finding the description that sounds closest to the waste being produced.

Some waste types have both hazardous and non-hazardous entries. Determining the appropriate classification can therefore require a better understanding of exactly what the waste contains.

However, this does lead to another useful procurement principle: Don’t assume the waste code tells the whole story.

When comparing quotations, make sure prospective suppliers are pricing against the same waste description, classification and supporting information.

Otherwise, two similar-looking prices may be based on very different assumptions about what will ultimately happen to the waste.

When Might Laboratory Analysis Be Needed?

Not every waste stream needs laboratory testing simply for the sake of producing another report.

Equally, relying on assumptions where the composition of a waste isn’t adequately understood can create unnecessary compliance and commercial risk.

The appropriate approach depends on factors such as:

• The process producing the waste
• Raw materials and chemicals involved
• Variability of the process
• Existing technical information
• Previous analysis
• The proposed treatment or disposal route

Safety Data Sheets can provide useful information where known products or chemicals are involved.

Where the composition cannot otherwise be established with sufficient confidence, chemical analysis may be required.

One important distinction for procurement teams is that Waste Acceptance Criteria (WAC) testing is not the same thing as waste classification. Environment Agency guidance specifically states that landfill WAC results must not be used for waste classification purposes.

Understanding what testing is actually required, and why, can prevent unnecessary analysis while ensuring suppliers have the information needed to propose an appropriate solution.

Why Classification Matters Commercially

Correct classification isn’t simply a paperwork exercise. It can materially affect the cost of managing waste.

Classification and characterisation can influence:

…and of course, classification can affect the overall cost!

Incomplete or inaccurate information can result in quotations being revised, loads being rejected or waste being directed towards an inappropriate or unnecessarily expensive management route.

Conversely, understanding a waste stream properly may identify treatment and recovery options that weren’t initially considered, and for procurement teams, this makes total waste management cost more meaningful than collection price alone.

A slightly higher collection or treatment price, for example, may represent better overall value if it enables recovery, reduces disposal requirements or provides a more resilient long-term management route.

Hazardous Waste Brings Additional Controls

Where waste is classified as hazardous, additional requirements apply.

In England, businesses producing or holding hazardous waste must classify it, store and separate it appropriately, use authorised organisations and complete the required documentation when the waste is moved.

The businesses involved in transporting and receiving the waste must also hold the appropriate registrations, permits or other authorisations for the activities they undertake.

This makes supplier due diligence particularly important. Procurement teams should understand and try to have these important questions answered:

Important Questions

• Who will collect the waste?
• Is the carrier appropriately registered?
• Where will the waste be taken?
• Is the receiving site authorised to accept it?
• What will happen to it at that facility?
• What documentation will be provided?

DHI Environmental Waste Transfer Station

The answers provide a much clearer picture of the proposed service than price alone.

Understanding Hazardous Waste Consignment Notes

When hazardous waste is moved in England, it generally needs to be accompanied by a correctly completed hazardous waste consignment note.

The document records important information about the waste and the organisations involved in its movement. It remains with the hazardous waste until it reaches its destination.

For waste producers, these documents form an important part of the compliance audit trail.

A good environmental waste supplier should make this process straightforward and ensure the appropriate information is captured consistently.

Procurement teams should therefore consider the quality of a supplier’s administrative and reporting processes alongside its operational capabilities.

Can hazardous and non-hazardous waste be mixed?

Segregation deserves particular attention because it can affect both compliance and cost.

Environment Agency guidance prohibits the mixing of hazardous waste with non-hazardous waste, non-waste or different categories of hazardous waste unless the mixing is specifically authorised and meets the applicable requirements.

There is also a strong commercial reason for keeping waste streams appropriately separated.

Consider a site producing several different liquid or sludge wastes.

If a non-hazardous or potentially recoverable material becomes contaminated with hazardous substances through poor segregation, the available treatment and recovery options may become more limited.

That can increase complexity and cost.

Effective segregation at source can support:

• Safer storage
• More accurate classification
• Appropriate treatment
• Better recovery opportunities
• Reduced cross-contamination
• More efficient collections
• Lower overall waste management costs

For procurement teams, it is therefore worth considering whether prospective suppliers simply collect existing waste streams or whether they can also identify opportunities to improve how those streams are managed on site.

Classification Should Influence the Treatment Route

A useful question for any waste management partner would be:

“What will happen to this waste after it leaves our site?”

Once waste has been appropriately characterised and classified, the available treatment, recovery and disposal routes can be assessed.

Depending on the waste, treatment may enable materials to be separated, contaminants to be managed or recoverable fractions to be diverted from disposal.

Other waste streams may require specialist treatment or, where no suitable alternative exists, disposal.

The important principle is that the management route should follow from an understanding of the waste, not the other way around.

This is where technical capability becomes an important part of supplier selection.

A provider able to consider different treatment and recovery routes may be able to offer a very different solution from a business primarily focused on collection and onward disposal.

Five Questions Procurement Teams Should Ask

When obtaining quotations for industrial liquid, sludge or packaged waste services, consider asking prospective suppliers:

The quality of the answers can tell you considerably more about a supplier than the collection price alone.

What Information Should You Provide When Requesting a Quotation?

Better information at the beginning of a procurement exercise generally allows suppliers to provide more accurate proposals.

Depending on the waste stream, useful information can include:

• A clear description of the waste
• The process that generates it
• Current LoW/EWC code and classification (search/find codes here)
• Safety Data Sheets where relevant
• Chemical analysis where available
• Estimated volume or tonnage
• Frequency of production
• Current storage arrangements
• Container or tank sizes
• Site access restrictions
• Required collection frequency
• Existing treatment or disposal route
• Known variations in the waste stream

Don’t worry if all of this information isn’t immediately available. If you need any assistance, you can contact us directly.

The response from prospective suppliers can itself be revealing.

An experienced provider should be able to explain what information is essential, what may be useful and whether further characterisation or analysis is required before an appropriate solution can be proposed.

Classification Isn’t Necessarily a One-Off Exercise

Waste streams can, and do change.

A manufacturer might introduce different raw materials. A food producer could alter its cleaning regime. A factory may change a chemical process, install new equipment or modify a production line.

Any of these changes could potentially alter the composition of the resulting waste.

This means waste classification shouldn’t simply be considered when a contract is first awarded and then forgotten.

Organisations should have processes for recognising significant changes to their waste streams and reviewing the classification and management arrangements where appropriate.

A good supplier relationship can support this by encouraging regular communication between operational, environmental and procurement teams.

Better Information Leads to Better Waste Management

For procurement professionals, hazardous waste classification can initially appear highly technical.

You don’t need to become a WM3 specialist. What matters is understanding enough to ask informed questions and recognising when specialist technical input is required.

Correct classification provides the foundation for appropriate storage, compliant transport, accurate documentation and suitable treatment, recovery or disposal.

It can also help organisations identify opportunities to improve segregation, explore alternative treatment routes and avoid unnecessary costs.

That’s why procuring environmental waste services should involve more than comparing a price per collection, tonne or cubic metre.

The strongest procurement decisions consider compliance, technical capability, treatment route, environmental performance and total cost together.

Learn More

DHI Environmental supports organisations with the management of hazardous sludges, non-hazardous sludges, hazardous liquids and packaged waste and non-hazardous liquids and packaged waste.

Whether you’re reviewing an existing waste stream or exploring alternative management options, explore our Environmental Services to learn more about the collection, treatment, recovery and waste management solutions available.