The Board may waive the examination requirement for licensure as a professional geologist for an applicant who (i) otherwise meets the requirements of this article; (ii) submits a written application to the Board; and (iii) holds an unexpired certificate of registration, certification, or license to engage in the practice of geology issued to him on the basis of comparable requirements by a proper authority of a state, territory, or possession of the United States or the District of Columbia.