A major step in the Louisville arena project will take place this Saturday morning.A ten story office building will be imploded to make way for the new facility at Second and Main Streets.The structure, formerly owned by Humana, Incorporated, is scheduled to be brought down at 7:00am Saturday. Demolotion contractor Michael O'Rourke says his company has spent monthspreparing the building for implosion."One thing that we do to control dust and debris is completely do an interior gut on the building. What we say is all combutible material is gone, all drywall all ceiling tiles, all carpet. And what the 201 West Main building looks like now is just a concrete shell," O'Rourke said.A public viewing area for the implosion will be set up in a city parking garageat First and Main Streets.A safety zone of one to two blocks will be set up around the site around 6:00amSaturday.