CHICAGO — Troy-based Kmart Corp. asked the U.S. Bankruptcy Court in Chicago for permission to hire Chicago-based Erwin Katz Ltd. as a mediator for 45 personal-injury lawsuits, the Detroit Free Press reported. Kmart would pay a $5,000 retainer, $4,000 for each day of work in Chicago, $5,000 for each day of work outside Chicago and $500 an hour for other services.