The 3rd area of the city is the Brell Sediment, the main feature of this area is a huge acid lake, which was formed by a former chemical plant in the area. If you are following the side quest, (this is for all classes), in the last area you were infected by the Rakghouls and you’ll want to go to C8-08-4 to figure out how to get the cure.
Because the out side area is mostly covered with the acid lake, you will spend most of your time in the former chemical plant for most of the quest. This area is kind of a let down, the quest don’t really have you explore the outside area. You’ll end up having very little of your map for this area reviled. You’ll be off to the Marsh (the last area in no time).
There is an interesting quest here (on the way to the Marsh). There is a unit of solider who have deserted there post, they been on the planet for year, and have seen to many of their friends die. You have a couple choices with them, and it doesn’t really effect much other than light or dark side point. But if you are really in to your character it can make you feel evil or good depending on what you do.