Code of Federal Regulations Title 10. Energy § 10.600.363 Collection of amounts due

(a) Any funds paid to a recipient in excess of the amount to which the recipient is finally determined to be entitled under the terms and conditions of the award constitute a debt to the Federal Government. If not paid within 30 days after the demand for payment, DOE may reduce the debt in accordance with the procedures and techniques described in 10 CFR part 1015 and OMB Circular A–129, including:

(b) Except as otherwise provided by law, DOE may charge interest and administrative fees on an overdue debt in accordance with 31 CFR Chapter IX, parts 900–904, “Federal Claims Collection Standards.”