Originally Posted by The Pants Party
Using a Molotov is likely your best bet here. The spread of fire is extremely large, so hold onto one until there is a mass of zombies and throw it as they charge you.
During Act 2 you can exit the church and see an ambulance on a bridge to the right. Head across it and aggro those zombies and the few at the end of the bridge as well. Run back and stand on top of the ambulance to get a group of ten, then drop your Molotov on top of them.
I couldn't find the area mentioned above. I found my spot in the resort along the beach. After you rescue the guy in the truck who opens your first bench, continue along the beach until you come across an island connected by a bridge to your right. There will be 11 or 12 zombies here.