This is a small Checkpoint by a tunnel, connecting to the Horse Lake checkpoint in the other side. There are only a handful of freakers in and around the compound so take them out as necessary. There are two speakers on the roof of the MMU and one on each guard booth along the road and the other one facing the tunnel.
There are two gas cans in this Checkpoint. The first one is found at the back of the parked truck, beside the MMU while the other one is located inside a tent.
The generator is right outside the MMU. After refueling it, you can turn it on. However, the power will still not be restored yet because of a blown fuse. First, find the NERO Fuse inside a container van near the tunnel entrance as shown below.
Next, interact with the power panel beside the MMU to replace the blown fuse and restore power to the Checkpoint. If done correctly, you just need to get inside and loot the items and the Injector inside.