The Old Mine is a base camp for Renegades when you first enter the Red Forest. It's best to stay away until Forester sends you there on a mission. The mine is located just inside the northern wall of the forest, along the western edge of the map. That is, just outside the area where Forester lives.
The main shaft runs east and west, with the entrance at the east. About two-thirds of the way into the mine is a ladder to a lower level that comes into play if you want the Firefly artifact or you are after the Experimental device. Then you must shoot one of the loose boards to be able to climb down the ladder. The lower level has a restroom to the north of the ladder that contains the Electro and Gas anomalies, along with the Firefly artifact. To the east is another Gas anomaly. The western end of the area slopes up along side the main shaft and is connected at the top. However, the connection is closed until you defeat two Poltergeist.
West of this the main shaft branches twice to the right. The first shaft is a dead-end and the second goes into a large storage area where the Compass artifact is. There is a connecting shaft at the western end of the area and the other shafts with some empty wooden boxes.
At first, Renegades hold the location. As you complete each task for Forester, he will eventually send you to the mine to retrieve the Compass. Once you clear the mine of the Renegades, some of the Duty guys by the northern gate will move in. However, sometimes the don't get to it right away and when they do, they have to clear out some Snorks.
- To get the Firefly artifact, sprint along the eastern wall of the room until you get to the storage box hanging on the wall. Now you're into the Gas and you'll probably need a medkit at this point. Next, crouch low and follow the edge of the room to the next area and the artifact.
- The storage area has three metal boxes and a green crate with lots of loot.