W. Va. Code § 22A-3-2
In every underground clay mine where five or more persons are employed in a period of twenty-four hours, the operator shall employ a mine foreman who shall be a competent and practical person holding a certificate of competence for said position issued to him or her by the office of miners' health, safety and training after an examination by such office. In order to receive a certificate of competence qualifying a foreman in an underground clay mine, the applicant shall take an examination prescribed by the director of the office of miners' health, safety and training, be a citizen of this state, of good moral character and temperate habits, having had at least three years' experience in the underground working of clay mines.
W. Va. Code § 22A-3-2