In order to determine the amount to be paid under section 434 of this title the Secretary of the Interior is authorized and directed to negotiate with said Indians to obtain their consent and relinquishment, and when such consent and relinquishment has been obtained and an agreement reached the Secretary of the Interior is further authorized to make payment from said donated fund for the lands relinquished to the enrolled members of the said Agua Caliente Band as authorized by section 434 of this title. The consent and relinquishment of the Indians may be obtained and payment made for the lands in such manner as the Secretary of the Interior may deem advisable. The water rights, dam, pipe lines, canals, and irrigation structures located in sections 2 and 3 of township 5 south, range 4 east, San Bernardino meridian, and also all water and water rights in Palm Canyon, are excepted from this reserve and shall remain under the exclusive control and supervision of the Bureau of Indian Affairs. The provisions of the Federal Power Act [16 U.S.C. 791a et seq.] shall not apply to this monument.