Jeremiah 
That beam is most likely not grounded unless for some reason they used it as a run for some copper pipe. Typically the steel beam will sit in a pocket that is formed up when they pour the foundation. It is seperated from the earth by a few inches of concrete. like drozenski said u should use a water line as your ground. If there isnt any close to your bench you could just ground the beam itself to the water line.
Bookmarks