30 U.S.C. § 287Section
§ 287. Extension of prospecting permits
Any prospecting permit issued under this subchapter may be extended by the Secretary of the Interior for a period not exceeding two years, upon a showing of satisfactory cause.
(Feb. 7, 1927, ch. 66, §7, as added May 7, 1932, ch. 174, 47 Stat. 151.)