The NRC may terminate collection activity when:
(a) The NRC is unable to collect any substantial amount through its own efforts or through the efforts of others;
(b) The NRC is unable to locate the debtor;
(c) Costs of collection are anticipated to exceed the amount recoverable,
(d) The debt is legally without merit or enforcement of the debt is barred by any applicable statute of limitations;
(e) The debt cannot be substantiated; or
(f) The debt against the debtor has been discharged in bankruptcy. [67 FR 30323, May 6, 2002]