Section 1208.12 - Payment requirements(a) All payments to ONRR by a purchaser of royalty oil will be due on the date and at the location specified in the contract, or, if there is no contractual provision, as specified by ONRR. The purchaser shall tender all payments to ONRR in accordance with § 1218.51 of this chapter. Payments made by a payor pursuant to the requirements of paragraph (b) of this section and § 1208.13 also shall be tendered in accordance with § 1218.51 of this chapter.(b)(1) Payments from a purchaser of royalty oil not received by ONRR when due, or that portion of the payment less than the full amount due, will be subject to a late payment charge equivalent to an interest assessment on the amount past due for the number of days that the payment is late at the underpayment rate applicable under section 6621 of the Internal Revenue Code of 1954.(2) The ONRR may assess interest to a payor for any underpayments which are the result of the payor's late or underreporting, or for adjustments reported by the payor, or made as a result of audit, reconciliation, or other procedures. The interest for late payment and underpayment will be assessed pursuant to § 1218.54 of this chapter.(c) If payment for royalty oil is not received by the due date specified in the contract, a notice of nonreceipt will be sent to the purchaser by certified mail. If payment is not received by ONRR within 15 days from the date of such notice, ONRR may cancel the contract and collect under the ONRR-specified surety instrument. See § 1208.11 .(d) If the purchaser disagrees with the amount of payment due, it must pay the amount due as computed by ONRR, unless the purchaser appeals the amount and posts an ONRR-specified surety instrument pursuant to the provisions of 30 CFR part 1243. The ONRR may, at its discretion, waive the appeal surety requirements if it determines that the contract surety instrument is sufficient protection for an amount under appeal.52 FR 41913, Oct. 30, 1987, as amended at 64901, Dec. 10, 1993