Jim: I saw this dumb-ass on reddit yesterday being an asshole to everybody, he even called an autistic kid a "dumb fucking faggot that should kill himself."
Bob: Oh don't worry about him, he was just working at the salt mine.
When a gentleman dips his penis in a Shamrock Shake followed by the pouring of salt all over his festive Irish junk. He then proceeds to infiltrate a thirsty woman's anal canal. Afterwards, the woman licks the penis like a Popsicle and swallows every salty drop.
"Did you hear about Josh's new occupation?"
"Yeah the Irish fuck mines salt from the anus of desperate women!"
"Wow! He's such a hardcore Celtic Salt Miner."
A male person who pleasures himself a bit too often or at opportune moments (like when a girlfriend is asleep or in the bath), a wanker, tosser, masturbator. Taken from the action of a miner using his tool at the source of the salt.
OMFG, did ya hear that Steve got caughtwanking at work, he's such a fucking salt miner.