can you use these drums for garden watering once it is clean?? Answered

Wash it thoroughly using degreasers and it should be fine. As others have noted, a metal container will eventually rust.

You can get those drums that are made out of plastic. They would be great for what you need and they wont rust obviously.

If the drum is metal build a fire inside it and get it red hot. That should clear any lingering oil residue from it. (at your own risk of course.)

maybe if you go to a scrap metal dealer, you might be able to find a different barrel there that had a non toxic substance in it and exchange them? offer them a few extra dollars and maybe they will do it.

You might be able to hunt down one of the blue or white plastic barrels as well?

Lots of chatter on this subject,

https://www.google.com/?q=cleaning+oil+from+oil+dr...

Someone even asked this same question to this same forum six years ago.

https://www.instructables.com/answers/I-have-a-55-g...

I actually don't know the answer to this one. It's going to be tricky to get every last trace amount of motor oil out of the drum, and it might not be possible to do it quickly.

Personally I would not use anything that had mineral oil in it.
It is next to impossible to fully clean them so the stink and the chemicals are gone.
If you check around you can get these caged 1000L containers quite cheap.
Just check what was in it, usually where they sell them second hand you only get them if there was nothing harmful in it to start with.