(1) Priority of claims for the appropriation of designated groundwater shall be determined by the doctrine of prior appropriation. All claims based on actual taking of designated groundwater for beneficial use prior to May 17, 1965, shall be determined by the doctrine of prior appropriation and shall relate back to the date of placing designated groundwater to beneficial use. All claims for the beneficial use of designated groundwater initiated after May 17, 1965, shall relate back to the date of filing of an application with the commission, unless such application is rejected.

(2) In order to establish priority of a claim to appropriate designated groundwater which has existed prior to May 17, 1965, a priority date shall be awarded to each well based upon the time the water was first applied to a beneficial use. The date shown in the records now filed in the state engineer's office shall be prima facie evidence of the date the water was first applied to beneficial use. All wells constructed as replacements for or as supplements to original wells for the same beneficial use shall be considered as a unit and awarded a priority date of the earliest well.

(3) As soon as practical after the establishment of a designated groundwater basin, the commission shall establish tentative priority dates for the respective wells within such designated groundwater basin, or subdivisions thereof, in accordance with the information contained in its files. The commission may require such additional information from the well claimant as will permit it to make a proper determination of the priority date and may request such other information as is required to be set forth in a final permit pursuant to section 37-90-108 (5). If the claimant fails or refuses to furnish the requested information within a period of thirty days, the commission may proceed to make a determination from the records available.

(4) After establishing the proposed priority date and after receiving the information required by section 37-90-108 (5) for the final permit on claims for the beneficial use of designated groundwater, the commission shall order the state engineer to issue a final permit to appropriate designated groundwater in the manner and pursuant to the standards set forth in section 37-90-108 for final permits; except that a final permit is not required to be issued for a well described in a conditional permit issued on or after July 1, 1991, to withdraw designated groundwater from the Dawson, Denver, Arapahoe, or Laramie-Fox Hills aquifers and except that this section shall not apply to any final priority lists established by the commission prior to January 1, 1985, and any final permits issued pursuant to said lists.

(5) and (6) Repealed.