WAC testing and soil classification explained.
Understand what your soil is, where it can legally go, and how to keep your muckshift moving — with sampling, UKAS lab analysis and the paperwork your receiving site needs.
WAC testing vs waste classification
Waste classification uses WM3 to decide whether your soil is hazardous or non-hazardous.WAC testing then decides which landfill cell or treatment facility can accept it.
Most disposal routes need both: classification tells you what the material is, WAC tells the receiving site whether it meets their acceptance limits. Without either, the tip can refuse the load.
We report both together — a WM3 hazard assessment, a WAC comparison, an EWC code, and the duty-of-care documentation the receiving facility needs.
The four soil classifications
Inert
- Examples:
- Clean natural clay, subsoil, crushed concrete from known sources.
- Typical route:
- Reuse on site, inert landfill, or recovery schemes.
- WAC scope:
- Usually a basic screen (metals, pH, sulphate, asbestos) rather than the full leachate suite.
Non-hazardous
- Examples:
- Made ground, mixed soils and trench arisings with low contaminant levels.
- Typical route:
- Non-hazardous landfill, soil treatment, or permitted recovery.
- WAC scope:
- Full WAC suite (BS EN 12457-3) plus WM3 hazard assessment.
Stable non-reactive hazardous (SNRHW)
- Examples:
- Soils that fail hazardous thresholds but meet the stable, monolithic criteria.
- Typical route:
- Dedicated hazardous landfill cell or stabilisation/treatment.
- WAC scope:
- Full WAC suite with hazardous-cell acceptance criteria.
Hazardous
- Examples:
- Contaminated soils exceeding HP8 toxic for disposal and other WM3 thresholds.
- Typical route:
- Hazardous landfill, treatment, or soil washing — consignment note required.
- WAC scope:
- Full WAC suite, WM3 hazard assessment and consignment documentation.
How WAC testing works
From first look at the site history through to a priced, permitted destination.
1. Desk study and sampling plan
We review site history, ground investigations and previous analysis, then set a sampling frequency that matches the volume and risk — typically one composite sample per 100–250 tonnes of consistent material, tightened across made ground.
2. Sampling on site
Samples are taken from stockpiles or excavation faces to BS EN 14899, logged with location and depth, and sent to the lab under chain of custody so results can be tied to a specific parcel of material.
3. UKAS lab analysis
Standard suites cover metals, pH, sulphate, TPH/PAH, asbestos screen and, where landfill is likely, the full WAC leachate suite to BS EN 12457-3. Turnaround is typically 3–5 working days.
4. Classification and route
Results are assessed against WM3 hazard-property thresholds and the receiving facility's Waste Acceptance Criteria. You get a clear classification — inert, non-hazardous, SNRHW or hazardous — with the reasoning stated.
5. Choose the disposal or recovery route
With the classification confirmed, we price the realistic options: recovery, soil treatment, permitted deposit-for-recovery, or landfill only where nothing better exists.
When do you need WAC testing?
WAC testing is not always required, but it is usually the gatekeeper for these disposal routes.
The material is going to landfill — inert, non-hazardous, SNRHW or hazardous cell.
The receiving treatment facility asks for a leachate suite before it accepts the load.
You need to prove a soil-treatment or recovery route is legally open.
The site has made ground, fill of unknown origin, or a known contamination history.
A tip, quarry or recovery scheme has asked for a WAC comparison as part of acceptance.
You want to compare landfill, treatment and recovery options on a like-for-like basis.
WAC testing FAQs
- What is WAC testing?
- Waste Acceptance Criteria testing is a leachate-based analysis, usually to BS EN 12457-3, that tells a landfill or treatment facility whether it can legally accept your material at a given cell. It is separate from hazard classification under WM3.
- What is soil classification?
- Soil classification decides whether a parcel of waste soil is inert, non-hazardous, stable non-reactive hazardous, or hazardous. It is based on laboratory analysis assessed against WM3 hazard-property thresholds.
- What is the difference between WM3 and WAC?
- WM3 is the UK government's guidance for hazardous waste classification — it decides whether the waste is hazardous. WAC testing decides which landfill cell or treatment facility can accept it. Most disposal jobs need both.
- Do I always need WAC testing before muck leaves site?
- No. If the material is reused on site under an appropriate exemption, or the receiving facility accepts it on a classification report alone, WAC may not be needed. It is normally required when the destination is a landfill or treatment facility.
- How many WAC samples do I need?
- As a guide, one composite sample per 100–250 tonnes of homogeneous material. Made ground, fill of unknown origin, or any sign of contamination needs more frequent sampling for the results to be defensible.
- How long does WAC testing take?
- Standard turnaround is 3–5 working days from the lab receiving samples. A 48-hour express option and a 24-hour rush option are available at a surcharge, subject to lab capacity.
- What happens if soil comes back hazardous?
- We price the realistic options rather than defaulting to hazardous landfill — soil treatment, stabilisation, or segregation of hot spots so the bulk can follow a cheaper route. Hazardous movements are consigned and documented accordingly.
- Can you take the samples for us?
- Yes. On-site sampling is carried out to BS EN 14899 with locations, depths and stockpile references logged, so results can be traced back to a specific parcel of material.
Local WAC testing across the UK
We sample, test and classify soils in and around these cities and regions. Click through for local service details.
What we need to quote
Send these five things and a price comes back within one working day — no site visit needed in most cases.
- 1Site postcode, and the delivery or collection window you're working to
- 2Material and tonnage — or the area and depth, and we'll work the tonnage back
- 3Access: whether an 8-wheeler can get in and tip, whether a grab has to reach over a boundary, or whether it has to be bulk bags
- 4Anything overhead or restrictive — cables, low gates, weight limits, permit or bay suspension
- 5Whether material is going out as well as coming in, so we can price it as one two-way movement
Related pages
Everything you need to spec, price and move material — tools, services and the exact material pages they relate to.
- Muckaway & soil removalSurplus dig, clay, hardcore and made ground removed to licensed facilities.
- Grab lorry hireSelf-loading 6- and 8-wheel grabs for stockpiles, verges and trench spoil.
- Compliance & paperworkWaste-carrier licensing, duty-of-care notes and WM3 documentation.
- How it worksFrom enquiry to delivered load — what we need and when things happen.
- Areas we coverCity-by-city delivery and haulage coverage across England, Scotland and Wales.
- Aggregate calculatorWork out tonnes and tipper loads from area and depth before you order.
Get your soil classified before it moves.
Tell us the site, the material and the volume, and we'll confirm the sampling plan, suite and turnaround.