; or (B) transfer those cost savings to the Hualapai OM&R Trust Account. (4) No reimbursement The Secretary shall not be reimbursed by any entity, including the Hualapai Tribe, for any amounts expended by the Secretary in carrying out this section. (5) Availability of amounts and investment earnings (A) In general Except as provided in subsection (a)(9)(B), amounts appropriated to and, deposited in, the Hualapai Water Project Account shall not be available to the Secretary for expenditure until the enforceability date. (B) Investment earnings Investment earnings under paragraph (2) on amounts deposited in the Hualapai Water Project Account shall not be available to the Secretary for expenditure until the enforceability date. (6) Authorization of appropriations (A) In general Subject to subparagraph (B), there is authorized to be appropriated to the Secretary for deposit in the Hualapai Water Project Account $134,500,000, to remain available until expended. (B) Fluctuation in costs The amount authorized to be appropriated under subparagraph (A) shall be increased or decreased, as appropriate, by such amounts as may be justified by reason of fluctuations in applicable engineering cost indices occurring after February 29, 2016, until the date on which title to the Hualapai Water Project is transferred to the Hualapai Tribe under subsection (a)(6)(A). (c) Hualapai OM&R Trust Account (1) Establishment (A) In general There is established in the Treasury of the United States a trust account, to be known as the Hualapai OM&R Trust Account , for the OM&R of the Hualapai Water Project. (B) Administration The Hualapai OM&R Trust Account shall be administered by the Secretary. (C) Composition The Hualapai OM&R Trust Account shall consist of the amounts deposited in the account under paragraph (4), together with any interest accrued on those amounts. (2) Management (A) In general The Secretary shall manage the Hualapai OM&R Trust Account in a manner that is consistent with— (i) the American Indian Trust Fund Management Reform