For many contractors, soil disposal is one of the most confusing parts of a project. Between waste classification rules, WAC testing requirements and the growing expectations under SWUK MCP, it’s easy for paperwork to pile up and mistakes to creep in.
This guide breaks down the essentials – what testing is required, what the results actually mean, and how tools like SoilComply help you stay organised, compliant and in control.
What is waste classification?
Waste classification determines what type of waste you have and how it must be handled. For excavated materials, this means assessing the soil to understand:
- Whether it is hazardous or non hazardous
- What contaminants are present
- Which disposal route is acceptable to the receiving site
Correct classification is a legal requirement under Duty of Care – and it forms the foundation for choosing the right disposal option.
When is waste classification required?
You must classify excavated soil every time it leaves site, unless it is being reused under an approved scheme (e.g., CL:AIRE DoWCoP).
Classification is required when:
- Excavating in previously developed land
- Working near industrial or commercial sites
- Removing made ground
- Handling materials with visible staining or odour
- Sending soil to a permitted waste facility
If in doubt, classify. Regulators expect a clear, evidence‑based approach.
What is WAC testing?
Waste Acceptance Criteria (WAC) testing determines whether soil is suitable for disposal at a particular landfill type (inert, non‑hazardous or hazardous).
WAC testing does not classify the waste – it simply confirms whether the chosen landfill can accept it.
When is WAC testing required?
WAC testing is typically required when:
- Soil is being sent to landfill
- The receiving facility requests it
- You need to confirm leachability or contaminant behaviour
- Classification results indicate borderline conditions
WAC testing is not required for all soils, but when it is, the results must be accurate, traceable and linked to the correct classification.
What do the results mean?
Waste classification results – These determine whether the soil is:
- Inert
- Non‑hazardous
- Hazardous
This classification dictates the legal disposal route.
WAC test results – These determine whether the soil meets the acceptance criteria for a specific landfill type.
For example:
- A soil may be non‑hazardous, but still fail inert WAC
- A soil may be hazardous, but still meet stable non‑reactive hazardous WAC
Understanding the difference is essential – and mixing up the two is one of the most common compliance errors.
Why contractors struggle with testing requirements
Across the industry, the same issues appear again and again:
- Missing or incomplete test reports
- Confusion between classification and WAC
- Lost documentation during handovers
- Misaligned responsibilities between contractor tiers
- Difficulty proving compliance during audits
With SWUK MCP raising expectations, the need for clarity and consistency has never been greater.
How SoilComply helps contractors stay organised and compliant
SoilComply was built to simplify the entire process – from classification to documentation to disposal.
✔ Clear, MCP‑aligned workflows: Guides users through each step so nothing is missed.
✔ Centralised documentation: All classification reports, WAC results and supporting documents stored in one secure place.
✔ Easy tracking and version control: No more lost PDFs, email chains or outdated files.
✔ Full traceability: Every action is logged, creating a complete audit trail for regulators and clients.
✔ Designed for every contractor tier: Promoters, Tier 1s, Delivery Contractors and Labs all follow the same structured process.
Waste classification and WAC testing don’t need to be complicated – but they do need to be done correctly. With clearer expectations under SWUK MCP, contractors need a reliable way to manage testing, documentation and compliance.
SoilComply gives you that clarity. A single platform to organise, track and evidence every step – with zero hassle and total confidence.
Want a simpler way to manage waste classification, WAC testing and SWUK MCP compliance?
Speak to our team to see how SoilComply can support your next project.