The tube in which sperm comes out of during ejaculation is the "Mine", while the workers are the sperm that come out. Workers in the Mines can be used as an innuendo for vasectomy or vasectomy reversal.
Vasectomy ex:
"I went to the doctor to get the workers trapped in the mines."

Vasectomy Reversal ex:

"I just felt bad for all those workers in the mines that need to get free"
by Nihcka July 11, 2018
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