42 C.F.R. § 86.18 – Grantee accountability.

(a) Accounting for grant award payments. All payments made by the Secretary shall be recorded by the grantee in accounting records separate from the records of all other grant funds, including funds derived from other grant awards. With respect to each approved project the grantee shall account for the sum total of all amounts paid by presenting or otherwise making available evidence satisfactory to the Secretary of expenditures for direct and indirect costs meeting the requirements of this part: Provided, however, That when the amount awarded for indirect costs was based on a predetermined fixed-percentage of estimated direct costs, the amount allowed for indirect costs shall be computed on the basis of such predetermined fixed-percentage rates applied to the total, or a selected element thereof, of the reimbursable direct costs incurred.
(b) Accounting for interest earned on grant funds. Pursuant to section 203 of the Intergovernmental Cooperation Act of 1968 (42 U.S.C. 4213), a State will not be held accountable for interest earned on grant funds, pending their disbursement for grant purposes. A State, as defined in section 102 of the Intergovernmental Cooperation Act, means any one of the several States, the District of Columbia, Puerto Rico, any territory or possession of the United States, or any agency or instrumentality of a State, but does not include the governments of the political sudivisions of the State. All grantees other than a State, as defined in this section, must return all interest earned on grant funds to the Federal Government.
(c) Grant closeout—(1) Date of final accounting. A grantee shall render, with respect to each approved project, a full account, as provided herein, as of the date of termination of grant support. The Secretary may require other special and periodic accounting.
(2) Final settlement. There shall be payable to the Federal Government as final settlement with respect to each approved project the total sum of:
1. (i) Any amount not accounted for pursuant to paragraph (a) of this section; and
2. (ii) Any credits for earned interest pursuant to paragraph (b) of this section; and
3. (iii) Any other amounts due pursuant to subparts F, M, and O of 45 CFR part 74.
  Such total sum shall constitute a debt owed by the grantee to the Federal Government and shall be recovered from the grantee or its successors or assignees by setoff or other action as provided by law.