(1) A low-level waste disposal site operator is exempt as specified in RCW 81.108.030(2)(a), 81.108.040(6), 81.108.050(7), 81.108.060(3), and 81.108.070(3) unless a monopoly situation exists with respect to the site operated by such site operator. A monopoly situation exists if either of the following is present:

(a) No disposal facility is available to Northwest compact generators of low-level radioactive waste other than the site or sites operated by such site operator or its affiliates; or

(b) Disposal rates at other sites are not reasonable alternatives for Northwest compact generators, considering: Disposal rates at other facilities; current disposal rates charged by the site operator; historic relationships between the site operator's rates and rates at other facilities; and changes in the operator's rates considering changes in waste volumes, taxes, and fees. A monopoly situation does not exist if either of the following facilities operates or is projected to operate after December 31, 1992:

(i) Any existing low-level radioactive waste disposal site outside the state of Washington, other than facilities operated by affiliates of a site operator, provided that such site or sites do not charge disposal rates that discriminate against Northwest compact generators, except to the extent, through December 31, 1994, such discrimination is authorized by amendment of current federal law.

(ii) An existing facility within the Northwest compact not receiving low-level radioactive waste offers to receive such waste under substantially similar terms and conditions.

(2) The exemption shall be in effect until such time as the commission finds, after notice and hearing, upon motion by the commission or upon petition by any interested party, that a monopoly situation exists or will exist as of January 1, 1993. The finding shall be based upon application of the criteria set forth in this section. The commission may assess a site operator for all of the commission's costs of supervision and regulation prior to and relative to determining whether the exemption applies to the site operator. If the commission determines that a site operator is not subject to the exemption, it shall collect its costs of supervision and regulation under RCW 81.108.090.

(3) When an exemption is in effect, any increase in the rates charged by the operator effective January 1, 1993, for services other than the base rate for disposal of solid material in packages of twelve cubic feet or less shall be no more than the percentage increase in the base rate in effect on January 1, 1993.