We don't have synonyms for coal cracker yet — it may be a rare, specialized, newly coined, or misspelled word. The closest thesaurus entries we have are corn cracker and cat cracker.
(n) :
(US, slang) A native or established resident of the traditional coal-mining area of northeastern Pennsylvania; a worker in the mines of this region.
(n) :
(US, slang) A native or established resident of the traditional coal-mining area of northeastern Pennsylvania; a worker in the mines of this region.