I don't live too far from I-64 but just have not been that way in a while but I am pretty sure there is still a bunch of construction going on. Illinois likes to get miles and miles of highway torn up and then take forever to finish a project. I would not think that traveling to Belleville on a Sunday the construction would delay you more than a half hour. But if there is an accident that can all change. You could always take Highway 15 from Mt. Vernon to Belleville. Highway 15 runs less than a 1/4 mile from the track. You can check this out as well:
http://www.navbug.com/traffic_condit...-64.htm#popmap
I hope this helps a little!