A past due, legally enforceable debt is a debt:

(a) That accrued within ten years of referral to Treasury;

(b) That is at least $25.00; and

(c) That the agency has made reasonable efforts to collect by:

(1) Submitting the debt to Treasury, Financial Management Service, for collection by Administrative Offset and complying with 31 U.S.C. 3716(a) and related regulations, to the extent that collection by administrative offset is not prohibited by statute;

(2) Notifying, or making a reasonable attempt to notify, the debtor that the debt is past-due, and unless repaid within 60 days after the date of the notice, will be referred to Treasury for tax refund offset;

(3) Giving the debtor at least 60 days from the date of notification to present evidence that all or part of the debt is not past-due or legally enforceable, considering any evidence presented by such debtor, and determining that an amount of such debt is past-due and legally enforceable; and

(4) Providing the debtor with an opportunity to make a written agreement to repay the amount of the debt.