The Washington Capitals will, assuming there is a next NHL season, practice in an ice rink being built on the eighth floor of a parking lot adjacent to Forest City's Ballston Common Mall. Open to the public, too — from 6 a.m. to midnight seven days a week, the rink should attract at least 750,000 visitors a year, says John Moore, VP and mall general manager. “Just think of all those parents of ice skaters who will kill time in the mall.”