I purchased three 59 gallon neutral barrels from a local winery. The barrels had just been emptied, cleaned and sulfur gassed. I am racking from carboys but have not had the time to do it for a month since I got the barrels. When I got the barrels one had a bung pop out as I was unloading and I got a strong dose of the sulfur gas. Now, though, after a month the gas smell is gone. The barrels still smell "sweet". My question is, should I wash them out again with a sulfur solution or is it safe to use as is? I would certainly prefer not having to wash them out. The cellarmaster told me not to worry about not filling them right away and that they would be fine empty for a while. Also, I had heard that by putting dry ice pellets in a barrel, CO2 will fill the barrel as the ice dissolves without leaving any residue and the oxygenation issue is lessened as the wine is racked into the barrel. Any thoughts?