Never pour waste oil down the drain as it is a major cause of water pollution. Follow the Oil Care Code (pdf).

Local councils have facilities for oil disposal. To find your nearest engine oil disposal site, go to the government site Oilbankline and type in your postcode (just the first part). You will get a comprehensive list of your nearest facilities. They also have a phone number, just in case you don’t find what you want: 08708 506 506.

I can’t find any specific information as to what actually happens to the waste oil – any information out there?