The construction manager for the Louisville arena project says there are currently about 250 workers on the job site, but that number will eventually swell to about 750.Mortensen Construction executive Bill Hedge says the project will ramp up with the addition of structural steel and exterior enclosures on the facility at Second and Main Streets.Construction is underway on the arena parking garage, concourses and the lower arena seating bowl.Arena Authority Chairman Jim Host says the project is back on track after crews encountered some unexpected excavation obstacles while working on the foundation."That's all been handled and you can see the progress that's coming out of the ground. We felt if we could get past the impediments aspect that once we got out of the ground it would move. We're on schedule and we're on budget," Host said Monday.The 22-thousand seat arena is scheduled for completion in November of 2010.A webcam view of the arena construction site can be seen here.