Hi

Are purpose built double walled fuel tanks acceptable. I have had a tank serviced recently (50k litres) and the engineer confirmed it was double walled and didnt think there was an integral bund, but they said the tank was fine and secondary containment wouldnt be necessary.

Guidance on Oil storage above ground (netregs.org.uk) seems to indicate otherwise?

Thoughts please?

Thanks

Generally if you have a tank built to the correct standard (BS799:5-2010, Type J, (Oil burning equipment). Also to recommendations made in ‘Oil Storage Regulations for Businesses’ (Environment Agency and Department for Environment, Food and Rural Affairs, England and Wales, 2018) and GPP2:Above Ground Oil Storage Tanks (Scotland and Northern Ireland).  I believe Oftec states BS799 as the build standard for storage tanks.) Then it should be fine and shouldn't need a secondary bund.  The outer wall of the tank has to have a separation distance from the inner tank such that the outer skin can hold 110%, this actually means that you don't need much separation distance because it is the total volume that counts, your double wall doesn't need to hold 110% just the outer skin.  Ours has a double skin and internal bunding which so far as I can ascertain means you are fine.