Is illegal to sponsor a drunk driving race?

I am putting on a first annual Drunk Driving Race across our city in 2 weeks but am concerned about the legalities of it (for me). Basically there are 6 people that have to drink 8 beers in 45 minutes (or enough to get them to .130). Once everyone is there we have a 35 minute route that takes them all around the city with the first one getting to the finish line getting 500. I know they can get DUIs but can I be held responsible for anything?