EWC Codes for Liquid Waste: The Operator's List

Every waste transfer note you issue needs a waste code on it. Most operators get handed the code once, early on, and use it for years without thinking about it — which is fine right up until the day someone offers you an interceptor job on the same round, and the code you have always used is the wrong one.

The full List of Waste runs to around 800 entries across 20 chapters. A cesspit and tanker operation uses about six of them. This is which six, and how to tell them apart.

What the Code Actually Is

The code goes by three names depending on who is talking. GOV.UK settles it in one line: your waste description must include "the waste classification code, also referred to as LoW (List of Waste) code or EWC (European Waste Catalogue) code." Same six digits, three labels.

The obligation sits on the producer first. According to GOV.UK's waste classification guidance: "You must classify the waste your business produces before it is collected, disposed of or recovered."

But in practice, on a domestic cesspit round, the producer is a householder who has never heard of the List of Waste. You are the one filling in the note, so you are the one who has to know the code — and the transfer note regulations put it there explicitly. Regulation 35(2)(a) of the Waste (England and Wales) Regulations 2011 requires the written information to "identify the waste to which it relates by reference to the appropriate codes in the List of Wastes".

The six digits are three pairs. The first pair is the chapter — where the waste came from. The second pair narrows the source. The third identifies the specific waste. For a domestic septic tank, chapter 20 is "municipal wastes", 20 03 is "other municipal wastes", and 20 03 04 is the one you want. For a sealed cesspool it is not — that load lives in chapter 16, and the next section explains why.

The Codes a Liquid Waste Operator Uses

These are quoted exactly as printed in the operative list — the annex to Commission Decision 2000/532/EC, as substituted by Decision 2014/955/EU. That is the list the regulations point to: regulation 3(1) of the Waste (England and Wales) Regulations 2011 defines "the List of Wastes" as "the list of wastes established by Commission Decision 2000/532/EC ... as amended from time to time".

A note on sources, because a lot of guidance still gets this wrong: the List of Wastes (England) Regulations 2005 were revoked on 1 July 2015 by regulation 10(a) of the Hazardous Waste (Miscellaneous Amendments) Regulations 2015. If a page cites SI 2005/895 for a waste code, it is citing revoked text — and in a few places that text now differs from the live list.

Chapter 20 03 — other municipal wastes

Code	Description as printed
20 03 04	septic tank sludge
20 03 06	waste from sewage cleaning
20 03 99	municipal wastes not otherwise specified

20 03 04 is the workhorse of the septic tank side of the round, and its printed description is the whole of its scope: septic tank sludge. Nothing in the List of Waste extends it to cesspools, and WM3 — the classification guidance you are pointed at for anything borderline — does not contain the word "cesspool", "cesspit" or "cess pit" anywhere in its 180 pages. The Environment Agency is blunter still. RPS 231 sets out, under the conditions you must comply with to rely on it: "You must not: … use the waste code 20 03 04 to describe waste other than untreated septic tank sludge". It carries no asterisk, so it is non-hazardous.

A cesspool is not a septic tank, and it does not take 20 03 04

This is the distinction most likely to put a wrong code on a real note, because the two jobs look identical from the cab.

A septic tank settles and partially treats what enters it — solids drop, liquor discharges to a drainage field. A cesspool is a sealed holding tank with no treatment and no outlet: everything that goes in stays there until you empty it. The two are physically different wastes, and the List of Waste treats them as such.

Cesspool waste is 16 10 02. RPS 241 Appendix 1 lists the codes a site may accept and gives, verbatim, "16 10 02: cesspool waste", adding that "where there is a mixed load of cesspool and sewage sludge you must list both on your waste duty of care documentation". The T21 exemption guidance says it in terms: "You should classify cesspool waste as '16 10 02 cesspool waste only' rather than using the 20 03 99 code."

Code	Description as printed	Use it for
16 10 02	aqueous liquid wastes other than those mentioned in 16 10 01	cesspool waste — the current code
20 03 99	municipal wastes not otherwise specified	cesspool waste — the legacy code some receiving sites still run

On 20 03 99: you will still meet it, because it is what the trade used for years and some receiving sites still key it. RPS 241 §3 records that "the Environment Agency is replacing waste codes ending in 99 with the 6-digit codes and descriptions listed in this RPS" — so treat 20 03 99 as the code you may be asked for, and 16 10 02 as the one to write.

One honest caveat. RPS 231 and RPS 241 are regulatory position statements scoped to particular permits and exemptions (T21, S3, SR2010 No. 5/6/17), so RPS 231's "must not" is a condition of relying on that RPS rather than a free-standing offence in its own right. That is a narrower point than it sounds. There is no source anywhere that positively supports writing 20 03 04 on a cesspool load, and every Environment Agency document that addresses cesspool waste directly routes it somewhere else. If your receiving site asks for something different, get it from them in writing and keep it with the note.

20 03 06 covers waste from sewage cleaning — drain and sewer cleaning arisings rather than tank contents. If your tanker does jetting and drain work alongside emptying, the two jobs are not the same code even when they go in the same tank.

20 03 99 is the fallback, and it should be rare. The List of Waste's own instructions put it last: if no code fits in chapters 01-12 or 17-20, check 13, 14 and 15; if none of those, check 16; and only then, in the list's own words, "If the waste is not in Chapter 16 either, the 99 code (wastes not otherwise specified) must be used in the section of the list corresponding to the activity identified in step one." Receiving sites are increasingly reluctant to accept 99 codes, and a note full of them looks like an operator who has not classified anything.

Chapter 19 08 — waste water treatment

Code	Description as printed
19 08 05	sludges from treatment of urban waste water

This one applies when you are lifting sludge from a treatment works or a package treatment plant rather than a domestic tank. Different source, different chapter, same tanker.

Where a Load Turns Hazardous

This is the part worth actually reading, because it changes the paperwork rather than just the description.

The List of Waste marks hazardous entries with an asterisk. In the source's own words: "Any waste marked with an asterisk (*) in the list of wastes shall be considered as hazardous waste for the purposes of any legislation relating to hazardous waste."

Chapter 13 05 is where a liquid waste operator meets that asterisk, and every entry in it is asterisked:

Code	Description as printed
13 05 01*	solids from grit chambers and oil/water separators
13 05 02*	sludges from oil/water separators
13 05 03*	interceptor sludges
13 05 06*	oil from oil/water separators
13 05 07*	oily water from oil/water separators
13 05 08*	mixtures of wastes from grit chambers and oil/water separators

Interceptors are the common one. A garage forecourt, a lorry park, a workshop yard, a car wash — all of them have an oil/water separator that needs emptying, and it is exactly the sort of job that gets offered to an operator who is already in the area with a tanker. The work looks identical to a cesspit lift. The waste is not.

There is also chapter 16 10, "aqueous liquid wastes destined for off-site treatment", which splits on contamination:

Code	Description as printed
16 10 01*	aqueous liquid wastes containing hazardous substances
16 10 02	aqueous liquid wastes other than those mentioned in 16 10 01
16 10 03*	aqueous concentrates containing hazardous substances
16 10 04	aqueous concentrates other than those mentioned in 16 10 03

Those pairings are the pattern to recognise. Where the list offers you an asterisked code and a plain one describing the same material, the difference is contamination — and the List of Waste's own rule for choosing between them is a property test, not an eyeball one. An asterisked entry "having a specific or general reference to 'hazardous substances', is only appropriate to a waste when that waste contains relevant hazardous substances that cause the waste to display one or more of the hazardous properties HP 1 to HP 8 and/or HP 10 to HP 15 as listed in Annex III to" the Waste Framework Directive. Concentration comes into it as the way those properties are assessed — "For the hazardous properties HP 4, HP 6 and HP 8, cut-off values for individual substances as indicated in Annex III to the Waste Framework Directive shall apply to the assessment" — and where a property has been assessed both by test and by concentration, the list says "the results of the test shall prevail".

Deciding which side of that line a load falls on is a classification judgement, and it belongs to the producer with the site knowledge — not to you, standing at the hatch. If nobody can tell you, that is the point to stop and ask rather than to guess low.

Why the Asterisk Changes Your Day

A non-hazardous load takes a waste transfer note. A hazardous load does not. GOV.UK is direct about it: "You must use consignment notes to move hazardous waste. A consignment note must stay with hazardous waste until it reaches its final destination."

The transfer note regulations agree from the other side. Regulation 35(7) of the 2011 Regulations disapplies the whole waste-transfer-note regime "where the waste transferred is hazardous waste and the consignment note and, where appropriate, schedule required by the Hazardous Waste (England and Wales) Regulations 2005 or the Hazardous Waste (Wales) Regulations 2005 are completed and dealt with in accordance with those Regulations."

So the code is not administrative detail. Pick 20 03 04 for a load that was actually 13 05 03*, and you have not filled in the wrong box — you have used the wrong document entirely, and the disposal site you are heading for may not be permitted to take it.

Practical consequences on a mixed round:

• Your disposal site has to be permitted for it. The works that takes your domestic sludge is very unlikely to be permitted for interceptor waste. Check before you accept the job, not after you have a full tanker.
• Don't mix them in the tank. Once hazardous waste is in with non-hazardous, the whole load is hazardous, and you have turned a routine round into a consignment-note job with nowhere obvious to tip it.
• The paperwork travels differently. A consignment note stays with the load to its final destination and passes through more hands than a transfer note does.

If you take interceptor work at all, it is worth deciding in advance whether it is a separate run or not a job you do — rather than deciding at 4pm with a part-full tanker.

Getting the Code Onto the Note

Whichever code applies, it has to be on the paperwork, along with the rest of what regulation 35 requires — quantity, container type, time and place of transfer, both parties' names and addresses and signatures, and your carrier registration number.

Our free liquid waste transfer note generator is pre-populated with the liquid-waste codes so the common cases are one selection rather than a lookup, and there is a fuller walkthrough of the document itself in our guide to completing a waste transfer note for liquid waste and in the full list of what every note must contain.

For codes outside the liquid-waste set, the Environment Agency's technical guidance WM3 carries the complete list plus the assessment method for the asterisked pairs — it is published on GOV.UK as waste classification technical guidance.

Scotland, Wales, and Northern Ireland

Everything above is sourced to the England and Wales position: the Commission Decision as it stands in the England and Wales statute book, and the Waste (England and Wales) Regulations 2011 for what the note has to carry.

WM3 is worth being precise about, because it is easy to assume it is an England document and send a Scottish reader elsewhere. It is not. Its cover names the publishing organisations as Natural Resources Wales, the Scottish Environment Protection Agency and the Environment Agency, and the current version is styled "Guidance on the classification and assessment of waste (1st Edition v1.2.GB)" — GB, so it speaks for England, Wales and Scotland.

What differs across a border is the surrounding regime and the regulator you answer to. Scotland runs special waste rather than hazardous waste, through SEPA. Northern Ireland's regime is administered by DAERA. NetRegs is the duty guidance for both — it describes itself as "Environmental guidance for your business in Northern Ireland & Scotland" — but it is guidance on the duties, not a copy of the code list. If you cross a border regularly, check the code list and the duties against the regulator for the nation the waste is produced in.

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