7.42—Payment of fees.

(g) DOT will assess interest on an unpaid bill starting on the 31st day following the day on which the notice of the amount due is first mailed to the requestor. Interest will accrue from the date of the notice of amount due and will be at the rate prescribed in 31 U.S.C. 3717. Receipt by DOT of a payment for the full amount of the fees owed within 30 calendar days after the date of the initial billing will stay the accrual of interest, even if the payment has not been processed.