(2) Any ordinance, rule or regulation enacted by a local unit of government of this state that encompasses the same matters as the state program shall be unenforceable, except for an ordinance, rule or regulation:
(a) That requires an owner or permittee to report a release to the local unit of government; or
(b) Adopted by a local unit of government operating an underground storage tank program pursuant to a contract entered into according to the provisions of ORS 466.730. [1987 c.539 §8 (enacted in lieu of 468.904)]