How to remove hair dye stains from a porcelain sink

If you have access to a steam cleaner you can try using the steam cleaner over the stained area for a few minutes to see if it will push the stain. If the stain is stubborn, you can try using your pressure washer after steam cleaning it and/or scrub the concrete. Let it dry and rinse and repeat, if it's still there.

Like The Evil Greebo asked, if the concrete isn't sealed, then the stain could be a bit difficult to remove or even permanent.

Best of luck!

No need for vinegar yet. The stuff is very water soluble. If you get the carpet too wet, you'll just transfer the sugars to the floor under the carpet. I'd put a wet, not slopping wet, towel on it, and let it sit overnight. The sugars should be drawn into the towel. It might take several applications. Once you've got most of it, go ahead and attack w a wet sponge/vinegar.