Iowa Code § 455H.302: Covenants not to sue.

Upon issuance of a no further action letter pursuant to section 455H.301, a covenant not to sue arises by operation of law. The covenant releases the participant and each protected party from liability to the state, in the state’s capacity as a regulator administering environmental programs, to perform additional environmental assessment, remedial activity, or response action with regard to the release of a hazardous substance for which the participant and each protected party has complied with the requirements of this chapter.