200.21  Compliance — a defense to certain nuisance actions.
  In a nuisance action or proceeding against an anhydrous ammonia plant brought by or on behalf of the person whose established date of ownership is subsequent to the established date of operation of an anhydrous ammonia plant, proof of compliance with applicable provisions of this chapter and applicable rules adopted pursuant to section 200.14 shall be a defense to a nuisance action or proceeding.
84 Acts, ch 1269, §2