; (iii) in the Fort Belknap Indian Community Clean and Safe Domestic Water and Sewer Systems, and Lake Elwell Project Account of the Trust Fund established under section 11012(b)(3), $110,628,407; and (iv) in the Fort Belknap Indian Irrigation Project System Account of the Implementation Fund established under section 11013(b)(1), $228,707,684. (B) Availability Amounts deposited in the accounts under subparagraph (A) shall be available without further appropriation. (3) State cost share The State shall contribute $5,000,000, plus any earned interest, payable to the Secretary for deposit in the Fort Belknap Indian Community Tribal Irrigation and Other Water Resources Development Account of the Trust Fund established under section 11012(b)(1) on approval of a final decree by the Montana Water Court for the purpose of activities relating to the Upper Peoples Creek Dam and Reservoir under subparagraphs (A) through (C) of section 11012(g)(1). (b) Fluctuation in costs (1) In general The amounts authorized to be appropriated under paragraphs (1) and (2) of subsection (a) and this subsection shall be— (A) increased or decreased, as appropriate, by such amounts as may be justified by reason of ordinary fluctuations in costs occurring after the date of enactment of this Act as indicated by the Bureau of Reclamation Construction Cost Index—Composite Trend