How to clean my Canton Wine Barrel for use

I recently bought a Canton Cooper's Select "Vintage" 255 ltr Bordeaux oak barrel from a woman who's father used it once for a Zinfandel before moving on. It is in new condition other than having dried up residue from the previous wine in it.

I need to thouroughly clean the inside and sanitize before use. Can anyone offer a safe procedure and solution to clean and sanitize this barrel? I have reached out to Canton but they do not respond.

Thanks in advance

maybe just soak it with water for a few days for the wood to expand, then sanitize it with star san like you would do a carboy.

I'd fill it with water and add some campden tablets. Not sure if that will kill off everything but I think it'd be a good start.