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19 11 05* Sludges from on-site effluent treatment containing hazardous substances

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

Hazardous Mirror entry (hazardous side)

Official description: “sludges from on-site effluent treatment containing hazardous substances”

Where it sits: chapter 19 (wastes from waste management facilities, off-site waste water treatment plants and the preparation of water intended for human consumption and water for industrial use), section 19 11 (wastes from oil regeneration).

What the hazard status means

This is one half of a “mirror” pair. Use this hazardous code if the waste contains hazardous substances above the thresholds, or has hazardous properties. You must assess the waste first, usually by knowing exactly what it is made of or by sampling and testing it.

Its mirror entry

19 11 06 Sludges from on-site effluent treatment other than those mentioned in 19 11 05 Not 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 19 11

19 11 01* Spent filter clays Hazardous
19 11 02* Acid tars Hazardous
19 11 03* Aqueous liquid wastes Hazardous
19 11 04* Wastes from cleaning of fuel with bases Hazardous
19 11 06 Sludges from on-site effluent treatment other than those mentioned in 19 11 05 Not hazardous
19 11 07* Wastes from flue-gas cleaning Hazardous
19 11 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.