(a) The Architect of the Capitol, under the direction of the House Office Building Commission, is hereby authorized to acquire, on behalf of the United States, by purchase, condemnation, transfer, or otherwise, for addition to the United States Capitol Grounds, all publicly or privately owned property contained in lot 49 in square 582; lot 70 in square 640; and lots 1, 2, 67, 79, 80, 800, 801, 807, 814 through 822, and 834 in square 693 in the District of Columbia (including all alleys or parts of alleys and streets within the lotlines and curblines surrounding such real property): Provided, That upon the acquisition of any such real property by the Architect of the Capitol on behalf of the United States, such property shall be subject to the provisions of the Act of July 31, 1946 (60 Stat. 718) [2 U.S.C. 1922, 1961, 1966, 1967, 1969; 40 U.S.C. 5101–5107, 5109, see References in Text note under section 1819 of Title 2, The Congress] as amended in the same manner and to the same extent as all other areas comprising the United States Capitol Grounds.
“(b) For the purposes of this section the properties authorized to be acquired hereunder, shall be deemed to extend to the outer face of the curbs of the squares in which they are located.
“(c) There is hereby authorized to be appropriated to the Architect of the Capitol for the fiscal year ending September 30, 1981, the sum of $11,500,000 for the purpose of carrying out the provisions of this section, said appropriation to remain available until expended.