10 C.F.R. § 15.51
The NRC may suspend or terminate collection action on a claim not in excess of the monetary limitation of $100,000 or such other amount as the Attorney General may direct, exclusive of interest, penalties, and administrative costs, after deducting the amount of partial payments or collections, if any of the debt has not been referred to the DOJ for litigation. If, after deducting the amount of any partial payments or collections, the principal amount of a debt exceeds $100,000, or such other amount as the Attorney General may direct, exclusive of interest, penalties, and administrative costs, the authority to suspend or terminate rests solely with the DOJ. If the NRC believes that suspension or termination of any debt in excess of $100,000 may be appropriate, the NRC shall refer the debt to the Civil Division or other appropriate litigating division in the DOJ, using the CCLR. The referral should specify the reasons for the NRC's recommendation. If, prior to referral to the DOJ, the NRC determines that a debt is plainly erroneous or clearly without legal merit, the NRC may terminate collection activity, regardless of the amount involved, without obtaining DOJ concurrence.
10 C.F.R. §15.51