(a) For ad valorem leases subject to §1206.257 of this subpart, ONRR shall, as authorized by this section, allow a deduction in determining value for royalty purposes for the reasonable, actual costs incurred to wash coal, unless the value determined pursuant to §1206.257 of this subpart was based upon like-quality unwashed coal. Under no circumstances will the authorized washing allowance and the transportation allowance reduce the value for royalty purposes to zero.

(b) If ONRR determines that a lessee has improperly determined a washing allowance authorized by this section, then the lessee shall be liable for any additional royalties, plus interest determined in accordance with §1218.202 of this chapter, or shall be entitled to a credit without interest.

(c) Lessees shall not disproportionately allocate washing costs to Federal leases.

(d) No cost normally associated with mining operations and which are necessary for placing coal in marketable condition shall be allowed as a cost of washing.

(e) Coal washing costs shall only be recognized as allowances when the washed coal is sold and royalties are reported and paid.