By Julia Burke, Beer Editor Award-winning brewer Jeff "Chief" O'Neil (pictured right) has announced that he is ending his nine-year tenure at Ithaca Beer Company to join The Peekskill Brewery as brewmaster, effective November 1. As Ithaca's brewmaster, O'Neil brought the Finger Lakes brewery national recognition with awards at the Great American Beer Festival and other  major events; thanks to his fierce skills and flair for innovation, honed at the Siebel Institute of Technology, such Ithaca offerings as Flower Power IPA and the Excelsior! Line (most notably Brute, a 2010 NYCR Beers of the Year finalist) have become sought-after gems…