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07 03 01* Aqueous washing liquids and mother liquors

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

Hazardous Absolute hazardous entry

Official description: “aqueous washing liquids and mother liquors”

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

Waste that matches this description is always hazardous waste, whatever the amount of hazardous substances in it. You do not need to test it to decide whether it is hazardous, but you still need to know its hazardous properties to fill in the paperwork.

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 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 12 Sludges from on-site effluent treatment other than those mentioned in 07 03 11 Not 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.

07 03 01* Aqueous washing liquids and mother liquors

What the hazard status means

Using this code

Other codes in section 07 03

Official sources