Woodinville whisky/maple barrel aging question

[robster]

Hi, I just ordered a freshly dumped 8 gallon barrel from Woodinville. It was whisky, then they aged maple syrup in it. I'm planning on filling it with an old raspuitin clone. How long can I leave the freshly dumped barrel empty? I'm sure the maple is going to attract mold and funk faster than whisky would. Anyone have experience with this? I do not want to sour the beer for at least a few uses! Any suggestions to keep it fresh up to a month while I make time to brew/ferment in carboys?
CO2 blanket? 5th of whisky and splash it around every few days?
Thanks, Rob

 

[BargainFittings]

I would get enough whisky back in the keg to keep any bad guys from growing. A good roll to coat the internals and dilute any of the sugar down so it is more alcohol than sugar will help.