With the hydroelectric dam back in business, ride back with Rikki to Lost Lake. On the way back, a cutscene will trigger, showing the blown transformer near a gas station.
You don’t have to do it now so just follow Rikki as she leads you to the Old Sawmill. There’s another cutscene showing you the massive Horde living in the area.
You also don’t have to do anything about it at the moment so ride again with Rikki after the cutscene all the way back to the Camp. As soon as you arrive, another cutscene will play and the mission will be complete.
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