T20 waste exemption: treating waste at a water treatment works
The T20 exemption allows you to treat certain waste at water treatment works to reduce the volume for transport, or to make it easier to handle for waste recovery.
Applies to England
Types of activity you can carry out
This includes storing and treating sludge from water clarification by removing water.
Types of activity you cannot carry out
You cannot:
- use this exemption to treat waste at locations other than at a water treatment works
- treat hazardous waste
Types of waste you can treat
The waste codes are those listed in the List of Wastes (LoW) Regulations. You need to make sure your waste fits within the relevant waste code and description.
| Waste code | Type of waste |
|---|---|
| 190902 | Sludge from water clarification |
| 190903 | Sludge from decarbonation |
| 190906 | Solutions and sludge from regeneration of ion exchangers |
| 190999 | Waste water and bore hole flushings only |
Quantity of waste you can treat
You can treat up to 10,000 cubic metres of waste over any 12-month period.
Key conditions
The waste must be treated and stored in a secure location with sealed drainage.
What else you need to know
You must not discharge dirty water to controlled waters or sewers without the correct consent. See Discharges to surface water and groundwater: environmental permits.
Related exemptions
U8 – using waste for a specified purpose.
T21 – recovering waste at a waste water treatment works.
Register a T20 exemption
You need to register this exemption with the Environment Agency if you meet the requirements.
Definitions
Secure – a container, lagoon or other place is secure in relation to waste kept in it if:
- all reasonable precautions are taken to make sure the waste cannot escape
- members of the public cannot gain access to the waste
Sealed drainage – a drainage system with an impermeable surface that makes sure that:
- no liquid will run off the surface apart from via the system
- except where they may be lawfully discharged, all liquids entering the system are collected in a sealed sump
Hazardous waste – see How to classify different types of waste.