Hi Ben,
When we expand our town's territorial claims we do our best to make sure that none of the territory has houses or other items owned by players, but unfortunately it's just not feasible for us to check out all of the underground cave systems as well.
That being said, we do apologize for claiming your mines and would be more than happy to pay you a good sum of noobz to make up for any income you may have lost, but we urge you to keep in mind that the mining world is the best place to do your mining, as issues like towns claiming caves don't occur there.
Feel free to /mail me in game and I'd be more than happy to work out a settlement.
Best,
Debo37