Except for any enrolled site which is the subject of an enforcement action by an agency of the state or the federal government prior to July 1, 1997, for any property where actions similar to a response action have commenced pursuant to any provision of chapter 455B prior to July 1, 1997, the person carrying out the action shall elect within ninety days following the final adoption of rules implementing this chapter to either continue to proceed in accordance with the laws and rules in effect prior to July 1, 1997, or to proceed pursuant to this chapter.
Iowa Code § 455H.507
97 Acts, ch 127, §31