(January 24, 2018, 2:37 PM EST) -- WILMINGTON, Del. — A retired U.S. bankruptcy judge will mediate a dispute between the Internal Revenue Service and reorganized chemical conglomerate W.R. Grace & Co. over a $1.6 million tax refund, according to a stipulation filed recently in a Delaware federal court appeal (In re: W.R. Grace & Co., et al., No. 17-cv-1588, D. Del.)....