I got one of these for a large camp (military) kitchen, and in copper as lots of dishes and pots might be cleaned:
Wash Basin, CopperDepending on what you are washing, you can get away with a pot scrubber and soap, followed by a good rinse. Some folks dig a small, but deep hole adjacent to the fire, to pour off the soapy water and the rinse water. The rinse is done by heating up some hot water, and ladling hot water into what you are cleaning, pour out and then let air dry.
For washing pots, many folks wipe out the interior, then add water and get it up to a boil for a bit..., this loosens the crud, and again a proper scrubber will get the pot clean..., dump and rinse with clean hot water, dump again and air dry.
The most elaborate kitchens use two of the basins, one for soapy water one for rinse, plus a large kettle for heating the hot water..., that pushes the cost for washing dishes like up to $200.

That's fine for large groups, but often waay too much for a single camp.
For fire buckets, you can maintain a large bucket or kettle of non-drinking water. This can be used with some bar soap for washing hands..., as if you need to use it on the fire that won't matter, but if you use drinking water buckets for you fire buckets as well, you need to keep the buckets filled. Some events won't allow this and demand dedicated fire buckets OR..., a small fire extinguisher (covered with canvas).
Some folks also use wooden buckets, and some use canvas buckets treated with Thompson's water seal..., the water then isn't potable, but the canvas buckets are easy to store when not in camp and are cheap. Not historically correct though, but then again a pair of "fire buckets" in a camp of any design probably isn't correct. The historic correct leather fire bucket sealed with pitch would be found with a fire "engine" in a town..., not a camp.
Canvas Bucket LD
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