Placarded tanker load into canada, does it need washed in canada?

So i have recently picked up a placarded load going from usa into canada. Can i re enter usa with residue from the delivery or do i have to get washed out at a tank wash in canada so i can be clean and dry.

It’s been awhile but i have done a few non placard loads to canada and i only remember the usa entry asking if i was empty.

i work for a smaller company and don’t know if they really know the requirements. I’m guessing the tank wash in Canada would be more expensive. So they are going to be motivated to just tell me to “try it” “maybe” “probably”

and i have dealt with this at a previous small company and there take on batteries.
I really don’t want to risk my cdl with this but i can’t find and answer with google or searching on the forum.

So would border/costums have an issue with this? The product was made in the usa and the residual is not getting delivered. It’s getting cleaned.

 

Thank you for your quick replies,
i really appreciate it.