I live in Lebanon, and if you told anyone who lived here there used to be coal mining in the county they would look at you funny. But back in the 1800's, Lebanon was the southernmost tip of mining in the Anthracite region. Mining failed in the mountain valley in the northern part of the county I believe because access to the area wasn't easy. I've been up there a few times (to play paintball and go fishing) and it is a really pretty area....but if you don't have 4 wheel drive getting there is almost impossible. It's a long hike to get up there. The valley is now a preserved rail trail natural area called Stony Creek Valley. There are several former towns along the rail trail, the one most used for mining was Rausch Gap where you can still see acid mine drainage today. Here is a website with info on the history of the area, and some historical maps. The mining info is mostly in the Rausch Gap section which is near the bottom of the page:
http://home.comcast.net/~stanthonywilderness/picpage.htm
Lebanon County sure is a weird place...it's like the dividing line between two vastly different regions of PA. to the north, including the northern tip of the county is the Anthracite region. to the south, including the southern half of the county, is all rolling farmland and Amish country.