Don6

I just neutralized my vinegar-zinc-rust sludge (barely any liquid left, the color of rust) with baking soda. I was surprised there was any reaction at all, but there was some foaming and bubbling. The sludge has been sitting outside evaporating for days. In my area of Nevada, there is a hazardous waste collection coming up in July. Thanks for all the helpful suggestions!

I've stripped zinc off galvanized metal with vinegar. Now I have a sludge of zinc, rust and a tiny bit of vinegar I suppose due to evaporation. What is a safe way to dispose of the sludge? Many thanks.