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07 03 12 Sludges from on-site effluent treatment other than those mentioned in 07 03 11

EWC / List of Waste code · Last checked 21 October 2026 · Applies across the UK (England, Wales, Scotland and Northern Ireland)

Not hazardous Mirror entry (non-hazardous side)

Official description: “sludges from on-site effluent treatment other than those mentioned in 07 03 11”

Where it sits: chapter 07 (wastes from organic chemical processes), section 07 03 (wastes from the MFSU of organic dyes and pigments (except 06 11)).

What the hazard status means

This is one half of a “mirror” pair. You can only use this non-hazardous code once you have assessed the waste and shown it does not contain hazardous substances above the thresholds and has no hazardous properties. If you are not sure, it must be treated as hazardous.

Its mirror entry

07 03 11* Sludges from on-site effluent treatment containing hazardous substances Hazardous

Using this code

Write the code on the paperwork when waste is passed on: a waste transfer note for non-hazardous waste, or a consignment note for hazardous waste (called special waste in Scotland).
Choose the code from where the waste came from first (the chapter), then what it is. If a load is mixed, you may need more than one code.
The waste must go to a site whose permit allows that code. A registered carrier can tell you which codes they accept: check a waste carrier.
Businesses have a duty of care to describe their waste correctly.

Other codes in section 07 03

07 03 01* Aqueous washing liquids and mother liquors Hazardous
07 03 03* Organic halogenated solvents, washing liquids and mother liquors Hazardous
07 03 04* Other organic solvents, washing liquids and mother liquors Hazardous
07 03 07* Halogenated still bottoms and reaction residues Hazardous
07 03 08* Other still bottoms and reaction residues Hazardous
07 03 09* Halogenated filter cakes and spent absorbents Hazardous
07 03 10* Other filter cakes and spent absorbents Hazardous
07 03 11* Sludges from on-site effluent treatment containing hazardous substances Hazardous
07 03 99 Wastes not otherwise specified Not hazardous

This page explains the code in plain English. It is not a classification of your waste. The official List of Waste and the classification guidance decide which code applies, and you are responsible for the code you use.