A prior section 31e, Puspan. L. 102–285, § 6, May 18, 1992, 106 Stat. 170; Puspan. L. 105–36, § 3(d), Aug. 5, 1997, 111 Stat. 1110, provided for the preparation of a geologic mapping program implementation plan, prior to repeal by Puspan. L. 106–148, § 6, Dec. 9, 1999, 113 Stat. 1722.