Section, Pub. L. 93–288, title VI, § 606, May 22, 1974, 88 Stat. 164; Pub. L. 95–51, § 1, June 20, 1977, 91 Stat. 233; Pub. L. 96–568, § 2, Dec. 22, 1980, 94 Stat. 3334, authorized appropriations of such sums as necessary to carry out this chapter through the close of Sept. 30, 1981.