I'm using a barrel for the first time. It's a brand new 10 gal
American Oak barrel. I've filled it with wine and everything seems
fine except that I'm noticing a 'wicking' phenomenon at the area
surrounding bung hole. This area is stained from the wine wicking out
around the bung. Is this normal? Perhaps just pressure equilization?

At first, I thought I had filled the barrel too much but this does not
appear to be the problem as removing wine to allow over an inch worth
of headspace does not change the result. I observe this with both
#8.5 and #9 rubber bungs which seem be the right size to give a good
seal. Any help is appreciated.

Thanks,
RD