(a)   (1) If ONRR determines that you took an unauthorized washing allowance, then you must pay any additional royalties due, plus late payment interest calculated under §1218.202 of this chapter.   (2) If you understated your washing allowance, you may be entitled to a credit without interest.

(b) If you improperly net a washing allowance against the sales value of the coal instead of reporting the allowance as a separate entry on Form ONRR-4430, ONRR may assess a civil penalty under 30 CFR part 1241.