You can do this achievement on the same playthrough you are using for the Hermit achievement. However, you will need to wait until the Hermit achievement pops and THEN you may go into town for this achievement.
This achievement requires you to spend 1 hour of real time in Concord. You will likely get this achievement naturally, as Concord has a variety of tasks to complete and lots of stuff to do. But if you don't have this achievement or this is the last achievement you need, just go idle in the town until you get it.