Just be darn careful that the stuff you're adding to that melted lead is DRY! Submerging wet stuff in melted lead is a sure way to see the tinsel fairy!
The best way to avoid adding wet alloy to the pot, is to never add the suspect material to a pot of molten alloy. This is especially applicable to WWs, where water can get trapped in small cracks and crevices, taking weeks or even months to dry.
When I smelt WWs, range scrap, or something that is not in ingot form, I run the pot (my dutch oven) completely dry, before adding more of the raw material. That way, the whole batch has a chance to come up to temperature and dry out, before there is enough molten alloy in the pot to allow the tinsel fairy to make an appearance.
Another help, is to not wash WWs (or range scrap). You're going to have to clean the dross and/or clips out, either way. So, what's a little dirt? It all floats, and you shouldn't be smelting that stuff in a bottom-pour furnace, anyway.