How to complete Source of the Contamination in Arc Raiders

When you help Celeste discover the contaminated water in the Water Troubles quest in Arc Raiders, naturally, she asks you to track down the source of the problem. This involves sending you to a hotspot on Dam Battlegrounds, which is what the Source of the Contamination quest is all about.

This isn't a particularly hard quest—you can figure out the location from its thumbnail—but you'll need to interact with a very specific spot, and it can be dangerous to reach, so here's what you need to do.