[minie]

The area right below Thorium Point has lots of 47-49 mobs, and there's a ton of kill/drop quests in that area. As long as you don't go down into the furnace area, they're spaced out enough that you don't have to worry about runners too much, and should be fine for a 48. There's some areas in that zone that are more 45-47 mobs (I think towards the NW side). Just avoid the elites in the area to the right of TP for a few levels and you should be fine.