(a.) All land and real property that are taxed based upon the gross product of a producing well, mine or mining claim shall be listed on the tax rolls by the County Assessor. Effective January 1, 1991, and thereafter, all tangible personal property used underground in mining or used within the well in oil or gas exploration or production as further described in paragraphs (b) - (e) below, that is taxed based upon the gross product of a producing well, mine or mining claim shall not be separately assessed. In accordance with the Wyoming Constitution and Statutes, the gross products tax shall be in lieu of property taxation of those lands and equipment, and shall be levied on all mineral interest owners in proportion to their ownership shares unless exempted by law. (6/91)
(b.) The amount of land allocated to such treatment shall be:
(c.) The types and amount of tangible personal property allocated to such treatment shall be only that capitalized equipment which historically has not been assessed and taxed based on the 1941 and 1963 Attorney General Opinions and which meets one of the following criteria:
(d.) In determining whether capitalized equipment satisfies the requirements of subparagraph (b)(ii) above, the taxpayer may submit, and the assessor may consider, information indicating that the equipment is specifically adapted for use underground or it is not put to any use other than the production of minerals in the underground operation.
(e.) The following shall not be relevant to the issue of whether the equipment is subject to separate assessment as personal property (that is, the following may occur without affecting the determination of whether the requirements in subparagraph (b)(ii) have been met):
(f.) All underground equipment and material of an oil or gas well plugged or temporarily abandoned pursuant to an approved Wyoming Oil and Gas Conservation Commission Form 4 in effect as of January 1st of each year shall have no assessment value for that year. All surface equipment remaining on a plugged or temporarily abandoned well shall be assessed.
(g.) If information is subsequently available to the assessor to conclude that equipment should have been subject to separate assessment as personal property, such equipment which had not been separately assessed in prior years shall be assessed and taxes computed and collected for the period the property was not separately assessed not to exceed five (5) prior years or since the last change of ownership, whichever is less.
(h.) Except as provided in paragraphs (b) - (e), equipment which is removed from underground shall be treated as tangible personal property and assessed accordingly. (6/91)
011-9 Wyo. Code R. § 9-15