Dist. Ct. erred in dismissing as untimely plaintiffs’ (Trustees of environmental trust fund) action under section 9607(a) of CERCLA seeking environmental clean costs incurred pursuant to 2002 Administrative Order of Consent (AOC) that required defendants to fund work called for by Enforcement Action Memorandum. Dist. Ct. improperly viewed plaintiffs’ action as essentially contribution claim under section 9613(f) of CERCLA, and wrongfully applied 3-year limitation period under 9613(g) since plaintiffs had not previously been subjected to any civil action under section 9606 or 9607 of CERCLA, which would be required to establish contribution claim under section 9613(f). Thus, plaintiff’s action under 9607 was timely since 2002 AOC was ongoing when instant lawsuit was filed, and any limitation period therefore had not yet started. Ct. further found that 10-year period applied with respect to plaintiffs’ Indiana state law claim for reimbursement of cleanup costs arising out of similar 1999 AOC between parties, even though plaintiffs were time-barred from seeking such costs under CERCLA. In doing so, Ct. rejected defendants’ claim that instant Indiana action was governed by 6-year limitation period applicable to actions for damages to real property.