Looking at the six questions you identify, a [tag:mining] tag seems pointless -- there's insufficient commonality between the subject matter for an "mining expert" to want to monitor the tag to identify questions they could answer.

Rather than proliferating tag to no good end, I'd rather see the effort go into improving our tag wikis which are quite frankly mostly rubbish.

ETA: Some context https://genealogy.meta.stackexchange.com/a/1716/104 which is my response to https://genealogy.meta.stackexchange.com/q/1715/104