(Richmond, IN)--Monday was the 58^th anniversary of the explosion in downtown Richmond.  Monday night, Richmond Mayor Ron Oler talked about a permanent memorial that will be installed.  "We had a committee of community leaders and council members design a bronze plaque that we're looking to get installed at the front of 6th and Main.  We came up with a final design a couple of weeks ago..got the names in alphabetical order of the 41 victims, Oler said.  The plaque is expected to be installed sometime this summer at the spot where Marting Arms once stood.