Nothing in this Act shall be construed as repealing or amending any provision of sections 702a, 702b to 702d, 702e to 702g, 702h, 702i, 702j, 702k, 702l, 702m, and 704 of this title. The authority conferred by this Act and any funds appropriated pursuant thereto for expenditure are supplemental to all other authority and appropriations relating to the departments or agencies concerned, and nothing in this Act shall be construed to limit or retard any department or agency in carrying out similar and related activities heretofore or hereafter authorized, or to limit the exercise of powers conferred on any department or agency by other provisions of law is ¹ carrying out similar and related activities.