Ariz. Rev. Stat. § 49-285 – Liability for remedial actions costs; limitation of actions

A. Except as otherwise provided in section 49-283, a person who is a responsible party shall be strictly and severally liable for such reasonable, necessary and cost-effective expenditures for remedial actions as are incurred by this state, a political subdivision of this state or any other person in a manner consistent with the rules and procedures adopted under section 49-282.06, but not including nonrecoverable costs. A responsible party may be held liable for remedial action costs for a release of a hazardous substance even though the conduct that resulted in the release or the release itself occurred before August 13, 1986.
B. In order to preserve any right to recover remedial action costs from responsible parties, remedial actions conducted by this state, a political subdivision of this state or any other person shall when evaluated as a whole be in substantial compliance with the rules and procedures adopted pursuant to section 49-282.06. The director's approval of a remedial action that is conducted by a person other than the state is not required to preserve any right to recover remedial action costs from potentially responsible parties. Any person other than the state who undertakes a remedial action may request that the director approve the remedial action as prescribed by rules adopted pursuant to section 49-282.06 at any time before, during or after the remedial action. The director's decision shall be in writing and shall specify the basis of the decision. Any remedial action so approved by the director shall be deemed to be in substantial compliance with the rules and procedures adopted pursuant to section 49-282.06. Any person who requests the director's approval of a remedial action shall reimburse the department for the total reasonable cost to the department for the review of the remedial action unless the director waives all or a part of the reimbursement. These monies shall be deposited in the water quality assurance revolving fund established by section 49-282. Costs that are reimbursed to the department by a party that obtains the director's approval of remedial actions pursuant to this subsection constitute remedial action costs that may be recovered from responsible parties.
C. Any person who is a defendant in an enforcement proceeding brought under section 49-287 may join in the action any other person who is or may be a responsible party.
D. Except as prescribed by section 49-283.01, this article does not affect or modify in any way the obligations or liability of any person, by reason of subrogation or otherwise, under any other provision of state or federal law, including common law, for damages, injury or loss resulting from a release of any hazardous substance or for remedial action costs, except that any person who receives compensation for remedial action costs pursuant to this article is precluded from recovering compensation for the same remedial action costs pursuant to any other federal or state law. Any person who receives compensation for remedial action costs pursuant to any other federal or state law is precluded from receiving compensation for the same remedial action costs as provided in this article.
E. In allocating several liability between two or more potentially responsible parties, the department, an allocator pursuant to section 49-287.06 or a court shall consider the following to determine each responsible party's allocated shares and the orphan shares:
1. 1. The amount and concentration of each hazardous substance involved.
2. 2. The degree of toxicity of each hazardous substance involved.
3. 3. The degree of involvement by the responsible parties in the generation, transportation, treatment, storage or disposal of the hazardous substance.
F. After the allocated shares and the orphan shares are determined pursuant to subsection E of this section and reduced to writing, the department, an allocator or the court may consider the following factors to adjust the allocated shares of the responsible parties, except that any adjustment under this subsection shall not adjust the amount allocated to orphan shares:
1. 1. The magnitude of the risk to human health or the environment caused by each hazardous substance involved.
2. 2. The degree of cooperation by the responsible party with federal, state or local officials to prevent any harm to the public health or the environment.
3. 3. Any other factors deemed relevant by the department, an allocator or the court in determining the liability of the parties under this section.
G. An action brought by a person other than the state to recover remedial action costs from a responsible party shall be brought within three years of the completion of the remedial action or within six years of the initiation of on-site physical construction activities for the remediation, removal or disposal of hazardous substances, whichever is earlier.
H. In an action brought for recovery of remedial action costs incurred at a site not on the registry maintained pursuant to section 49-287.01 or that is brought pursuant to section 49-287.07, subsection A, paragraph 3, subdivision (a), (b) or (d), the court shall initially allocate costs among the responsible parties based on the factors listed in subsection E of this section. To the extent that the allocation results in costs being allocated to orphan shares, those costs shall be reallocated to the responsible parties based on such equitable factors as the court deems appropriate, including:
1. 1. The factors listed in subsection F of this section.
2. 2. Each responsible party's ability to pay.
3. 3. The degree of care exercised by each responsible party with respect to the hazardous substance of concern and taking into account the characteristics of that substance.