The legislative power of Guam shall extend to all rightful subjects of legislation not inconsistent with the provisions of this chapter and the laws of the United States applicable to Guam. Taxes and assessments on property, internal revenues, sales, license fees, and royalties for franchises, privileges, and concessions may be imposed for purposes of the government of Guam as may be uniformly provided by the Legislature of Guam, and when necessary to anticipate taxes and revenues, bonds and other obligations may be issued by the government of Guam: Provided, however, That no public indebtedness of Guam shall be authorized or allowed in excess of 10 per centum of the aggregate tax valuation of the property in Guam. Bonds or other obligations of the government of Guam payable solely from revenues derived from any public improvement or undertaking shall not be considered public indebtedness of Guam within the meaning of this section. All bonds issued by the government of Guam or by its authority shall be exempt, as to principal and interest, from taxation by the Government of the United States or by the government of Guam, or by any State or Territory or any political subdivision thereof, or by the District of Columbia. The Secretary of the Interior (hereafter in this section referred to as “Secretary”) is authorized to guarantee for purchase by the Federal Financing Bank bonds or other obligations of the Guam Power Authority maturing on or before December 31, 1978, which shall be issued in order to refinance short-term notes due or existing on June 1, 1976 and other indebtedness not evidenced by bonds or notes in an aggregate amount of not more than $36 million, and such bank, in addition to its other powers, is authorized to purchase, receive or otherwise acquire these same. The interest rate on obligations purchased by the Federal Financing Bank shall be not less than a rate determined by the Secretary of the Treasury taking into consideration the current average market yield on outstanding marketable obligations of the United States of comparable maturities, adjusted to the nearest one-eighth of 1 per centum, plus 1 per centum per annum. The Secretary, with the concurrence of the Secretary of the Treasury, may extend the guarantee provision of the previous sentence until December 31, 1980. The Secretary, upon determining that the Guam Power Authority is unable to refinance on reasonable terms the obligations purchased by the Federal Financing Bank under the fifth sentence of this section by December 31, 1980, may, with the concurrence of the Secretary of the Treasury, guarantee for purchase by the Federal Financing Bank; and such bank is authorized to purchase, obligations of the Guam Power Authority issued to refinance the principal amount of the obligations guaranteed under the fifth sentence of this section. The obligations that refinance such principal amount shall mature not later than December 31, 1990, and shall bear interest at a rate determined in accordance with section 2285 of title 12. At the request of the Board of Directors of the Guam Power Authority for a second refinancing agreement and conditioned on the approval of the Government of Guam pursuant to the law of Guam, and conditioned on the establishment of an independent rate-making authority by the Government of Guam, the Secretary may guarantee for purchase by the Federal Financing Bank, on or before December 31, 1984, according to an agreement that shall provide for—

(a) substantially equal semiannual installments of principal and interest;

(b) maturity of obligations no later than December 31, 2004;

(c) authority for the Secretary, should there be a violation of a provision of this legislation, or covenants or stipulations contained in the refinancing document and after giving sixty days notice of such violation to the Guam Power Authority and the Governor of Guam, to dismiss members of the Board of Directors or the general manager of the Guam Power Authority, and (1) appoint in their place members or a general manager who shall serve at the pleasure of the Secretary, or (2) contract for the management of the Guam Power Authority; and

(d) an annual simple interest rate of seven per centum; and

the Federal Financing Bank shall purchase such Guam Power Authority obligations if such Guam Power Authority obligations are issued to refinance the principal amount scheduled to mature on December 31, 1990. Should such second refinancing occur, (1) the independent rate-making authority to be established by the Government of Guam, or in its absence, the Board of Directors of the Guam Power Authority, shall establish rates sufficient to satisfy all financial obligations and future capital investment needs of the Guam Power Authority that shall be consistent with generally accepted rate-making practices of public utilities, and (2) the Government of Guam shall not modify the requirements of such refinancing agreement without agreement of the Secretary. There are authorized to be appropriated to the Secretary of the Interior for payment to the Federal Financing Bank such sums as are necessary to pay (1) the repurchase payment required under the fifth paragraph of the December 31, 1980, note from the Guam Power Authority to the Federal Financing Bank and any subsequent repurchase payments required under the second refinancing agreement, and (2) the interest rate differential between the seven per centum to be paid by the Guam Power Authority and the second refinancing agreement and the interest rate that would otherwise be determined in accordance with the above cited section 2285 of title 12. Should the Guam Power Authority fail to pay in full any installment of interest or principal when due on the bonds or other obligations guaranteed under this section, the Secretary of the Treasury, upon notice from the Secretary shall deduct and pay to the Federal Financing Bank or the Secretary, according to their respective interests, such unpaid amounts from sums collected and payable pursuant to section 1421h of this title. Notwithstanding any other provision of law, Acts making appropriations may provide for the withholding of any payments from the United States to the government of Guam which may be or may become due pursuant to any law and offset the amount of such withheld payments against any claim the United States may have against the government of Guam or the Guam Power Authority pursuant to this guarantee. For the purpose of this chapter, under section 3713(a) of title 31 the term “person” includes the government of Guam and the Guam Power Authority. The Secretary may place such stipulations as he deems appropriate on the bonds or other obligations he guarantees.