Full opinion text
DeGUILIO, District Judge. This appeal is the latest chapter in the story of the Environmental Chemical and Conservation Company (“Enviro-Chem”), a defunct Indiana corporation with an expensive environmental legacy. EnviroChem conducted waste-handling and disposal operations at three sites north of Zionsville, Indiana, until it closed its doors in the early 1980s, and it left considerable amounts of pollutants behind. The plaintiffs in this action are the trustees of a fund created to finance and oversee the cleanup project at one of those three sites. The defendants are the former owners of the site, their corporate entities (including Enviro-Chem), and their insurers, none of whom have paid into the trust despite an alleged obligation to do so. The plaintiffs sued to recover cleanup costs under the Comprehensive Environmental Response, Compensation and Liability Act (“CERCLA”), the Indiana Environmental Legal Actions Statute (“ELA”), and more. The district court dismissed all claims at the summary judgment stage, and the plaintiffs appealed. In response, one of the insurance companies targeted by the plaintiffs filed a conditional cross-appeal, hoping to preserve a favorable outcome even in the event of a reversal of the district court’s final judgment. On December 19, 2012, this panel decided both appeals, affirming in part and reversing in part the district court decision and remanding the case for further proceedings on the reinstated claims. Bernstein v. Bankert, 702 F.3d 964 (7th Cir.2012). The defendants-'appellees requested a panel rehearing, and the Environmental Protection Agency joined their request as amicus curiae. While we conclude that the arguments advanced by the parties do not warrant reconsideration of our decision, we grant rehearing, in part, to address some issues raised by the EPA. Specifically, the EPA identified certain passages of our original opinion which suggested that a party may never structure a settlement agreement with the EPA in such a way as to resolve their liability immediately upon execution of that agreement. That is not the case. A party responsible for an instance of environmental contamination may obtain an immediately effective release from the EPA in a settlement, or it may obtain only a performance-dependent conditional covenant not to sue with an accompanying disclaimer of any liability. Whether, and when, a given settlement “resolves” a party’s liability to the EPA within the meaning of 42 U.S.C. § 9613(f)(3)(B) is ultimately a case-specific question dependant on the terms of the settlement before the court. In this case, the terms of the administrative settlement did not provide for a resolution upon entering into the agreement. The following constitutes this panel’s amended opinion superseding our prior opinion and resolving the appeals in both Nos. 11-1501 and 11-1523. BACKGROUND The appellants — plaintiffs below — are the trustees of the Third Site Trust Fund (“Trustees”). Third Site is a CERCLA site located about five miles north of Zionsville, Indiana. Along with two other CERCLA sites in close proximity — the Enviro-Chem Site to the north and the Northside Sanitary Landfill (“NSL”) to the northeast — Third Site was owned and operated by the Bankert family and their corporate entities at all times relevant to this litigation. Up until the early 1980s, Enviro-Chem, one of those entities, was engaged in brokering and recycling industrial and commercial wastes at all three sites. It is undisputed that EnviroChem’s operations extended to Third Site; historical aerial photographs depict Third Site being used for tank and drum storage, and former Enviro-Chem employees have indicated that Third Site hosted waste handling and disposal operations. Enviro-Chem ceased operations in 1982, and shortly thereafter the United States Environmental Protection Agency (“EPA”) undertook an extended effort to clean up the mess it left behind. The cleanup initially focused on the Enviro-Chem Site and the NSL, but in 1987 and 1992 consultants collected soil, groundwater, seepage soil and seepage water samples from Third Site. The samples indicated elevated concentrations of volatile organic compounds (“VOCs”) and semi-volatile organic compounds (“SVOCs”) in the areas tested. Similarly, surface water samples collected by the EPA in 1988 from nearby Finley Creek showed elevated levels of VOCs immediately adjacent to and downstream from Third Site. These results were consistent with additional samples collected in 1985 and 1986 from surface seeps discharging from Third Site and into Finley Creek. In short, Third Site was polluted, and it was transferring its pollutants to Finley Creek. Finley Creek flows south into Eagle Creek Reservoir, and Eagle Creek Reservoir supplies a portion of the drinking water for the City of Indianapolis. The pollution of Finley Creek was therefore cause for real concern. In 1996, the EPA countered the threat by issuing a Unilateral Administrative Order (“UAO”) outlining a plan to realign Finley Creek. The plan called for eliminating an oxbow, the top of which touched areas of high contamination at Third Site, and for rerouting the creek away from the site and to the south. The realignment project was designated a time-critical removal project, and the respondents to the UAO completed, it in September 1996. Subject to periodic maintenance inspections, the EPA approved their performance. Having averted any significant corruption of the drinking water supply, the EPA turned its attention to cleaning up Third Site itself. In October 1999, the EPA entered into an Administrative Order by Consent (“AOC”) with a number of respondents, each of whom was designated a potentially responsible party (“PRP”) for contamination at the site. The 1999 AOC was divided into two separate parts: one dealing with “Non-Premium Respondents” and one dealing with “Premium Respondents.” The Non-Premium Respondents agreed to undertake an Engineering Evaluation and Cost Analysis (“EE/CA”) of removal alternatives for Third Site. They also agreed to settle a trust — the Third Site Trust, of which the appellants are Trustees — and to fund it to the extent necessary to bankroll the EE/CA and any additional necessary work. Through the Trust, they would reimburse the EPA for past response and oversight costs as well as future oversight costs incurred in conjunction with the EE/CA project. The Premium Respondents, on the other hand, were alleged to be de minimis contributors to the contamination at Third Site. They were entitled to settle out with a defined, onetime monetary contribution to the Trust consistent with 42 U.S.C. § 9622(g). The Non-Premium Respondents met their obligations under the 1999 AOC and obtained EPA approval of the final EE/CA report on October 24, 2000. No copy of the EPA notice of approval was included in the record, and we only know of it through affidavits submitted with the parties’ summary judgment briefs. But, in any case, the parties do not dispute that the 1999 AOC was complied with fully to its completion. In 2001, subsequent to approving the work done under the 1999 AOC, the EPA issued an Enforcement Action Memorandum selecting one of the removal actions for the site identified by the EE/CA and outlining cleanup objectives. In November 2002, the parties entered into a second AOC to perform the work called for by the Enforcement Action Memorandum. For the most part, the 2002 AOC tracked the form of the 1999 AOC. It included separate provisions addressing the responsibilities of Premium and Non-Premium Respondents and contained the same reservation of rights and conditional covenants not to sue. Furthermore, the Non-Premium respondents maintained the same responsibilities vis-avis the Trust, which was once again assigned to manage the removal effort. At the time this lawsuit was filed, the work to be performed under the 2002 AOC was still ongoing, and no EPA notice of approval had issued. Under the terms of the 1999 and 2002 AOCs and the corresponding Trust Agreement, the Trustees are empowered to hold and manage funds; to retain engineers and others to carry out the work to be performed under the AOCs; to project future costs; to obtain additional funds as needed from the settlors (i.e., the Non-Premium Respondents); and, subject to prior approval, to bring suit against those who do not meet their obligations to the Trust. The Bankert appellees were listed as Non-Premium Respondents under the 1999 and 2002 AOCs, but have not met their obligations by paying into the Trust or otherwise. On April 1, 2008, the Trustees filed a Complaint against the Bankerts and their various insurers in the Southern District of Indiana with six counts: Count I, a CERCLA cost recovery action pursuant to 42 U.S.C. § 9607(a); Count II, seeking a declaratory judgment under CERCLA of the defendants’ joint and several liability; Count III, a cost recovery action under the ELA, codified at I.C. § 13-30-9-2; Count TV, negligence; Count V, nuisance; and Count VII, seeking a declaratory judgment of coverage against the insurers. On May 30, 2008, one of the Bankerts’ former insurers, Auto Owners Mutual Insurance Company (“Auto Owners”), moved to dismiss the Trustees’ Complaint against it pursuant to Federal Rules of Civil Procedure 12(b)(6) and 12(d). The coverage provisions of Auto Owners’s policies with the Bankerts were previously litigated in connection with cleanup efforts at the Enviro-Chem Site in the 1980s, and Auto Owners argued that the favorable judgment it obtained in that case precluded a finding of coverage in this case. On September 17, 2008, the district court converted the portion of Auto Owners’s motion claiming preclusion to a motion for summary judgment and permitted the parties to conduct discovery and submit additional briefing. On March 16, 2010, the district court entered an order denying the motion. On September 22, 2009, the Bankerts moved for summary judgment on statute of limitations grounds. The Trustees responded, and the Bankerts replied. On December 10, 2009, the Trustees moved to strike a portion of that reply or, in the alternative, for permission to file supplemental briefing. The district court heard oral argument on August 3, 2010. On September 29, 2010, the district court denied the Trustees’ motion to strike and granted summary judgment in the Bankerts’ favor. First, the district court found that the Trustees could not bring a CERCLA cost recovery claim under 42 U.S.C. § 9607(a), which is what Count I of the Complaint purported to do. Instead, the district court construed the Trustees’ CERCLA claim as one for contribution pursuant to 42 U.S.C. § 9613(f). Next, the district court found that the statute of limitations applicable to that kind of CERCLA claim had run. This, in turn, invalidated the declaratory judgment request contained in Count II. Finally, the district court found that the statute of limitations had run with respect to each of the Trustees’ state law claims against the Bankerts. Counts I through V were dismissed. Next, the district court asked the parties to report on the status of Count VII, which sought a declaratory judgment of coverage against Auto Owners and the other insurers. All parties conceded that it was moot; insurance coverage was a non-issue without a controversy over the underlying liability. On October 13, 2010, the Trustees moved the court to reconsider the grant of summary judgment with respect to the ELA claim and to certify the question to the Indiana Supreme Court. On February 3, 2011, the district court denied that motion and entered final judgment in favor of the defendants, dismissing Count VII as moot consistent with the parties’ positions. The Trustees filed a timely notice of appeal on March 3, 2011, and Auto Owners cross-appealed. We take up each appeal in turn. THE TRUSTEES’ APPEAL The Trustees appeal the district court’s dismissal at the summary judgment stage of their CERCLA and ELA claims, as well as the dismissal of their declaratory judgment claim against Auto Owners. They also appeal the district court’s denial of their motion to strike a portion of the Bankerts’ summary judgment reply. They have not appealed the district court’s dismissal of their state law negligence and nuisance claims, and as a result those claims are lost. We find that the Trustees have, in fact, pled a timely CERCLA cost recovery claim, although the scope of their recovery will be limited. As a result, Counts I and II must be reinstated. Count III, claiming contribution under the Indiana ELA, is timely as well. Reinstating those claims means there is a live controversy over liability, and so we must reverse the district court’s dismissal of Count VII as moot. I. Counts I and II: CERCLA Claims In Count I of their Complaint, the Trustees seek to recover funds which the Bankerts allegedly owe to the Third Site Trust pursuant to obligations created by the 1999 and 2002 AOCs. The Trustees characterize Count I as a claim for cost recovery under 42 U.S.C. § 9607(a), but the district court held: (1) that a § 9607(a) claim was unavailable to the Trustees; (2) that their claim must therefore be one for contribution under § 9613(f); and (3) that the limitations period for a contribution claim had run. Count II, seeking a declaratory judgment of liability, is essentially a derivative claim; once the district court concluded that Count I was not timely, Count II had to be dismissed as well. We review a district court’s grant of summary judgment based on a statute of limitations de novo. Stepney v. Naperville Sch. Dist. 203, 392 F.3d 236, 239 (7th Cir.2004). To the extent we are called upon to review the district court’s interpretation of the statute, the standard of review is likewise de novo. Storie v. Randy’s Auto Sales LLC, 589 F.3d 873, 876 (7th Cir.2009). We are mindful, too, of the deference typically accorded to the summary judgment non-movant with respect to the resolution of factual issues, but note that this dispute is almost entirely a legal one, with the underlying facts undisputed: the Bankerts argue that the Trustees have advanced one type of CERCLA claim, and that it is barred by the statute of limitations; the Trustees argue that they have advanced another type of claim, and that it is not. They are both partially correct, but the net result is that the district court must be reversed with respect to Count I. That, in turn, is enough to revive Count II. Finally, we find no abuse of discretion in the district court’s denial of the Trustees’ motion to strike portions of the Bankerts’ summary judgment reply. A. CERCLA and SARA Statutory Scheme In 1980, Congress enacted the Comprehensive Environmental Response, Compensation, and Liability Act, 42 U.S.C. §§ 9601-9675, in response to the serious environmental and health risks posed by industrial pollution. Burlington Northern and Santa Fe Ry. Co. v. United States, 556 U.S. 599, 602, 129 S.Ct. 1870, 173 L.Ed.2d 812 (2009) (citing United States v. Bestfoods, 524 U.S. 51, 55, 118 S.Ct. 1876, 141 L.Ed.2d 43 (1998)). CERCLA is not known for its clarity, or for its brevity. Exxon Corp. v. Hunt, 475 U.S. 355, 363, 106 S.Ct. 1103, 89 L.Ed.2d 364 (1986) (noting CERCLA provisions are “not ... models] of legislative draftsmanship,” and its statutory language is “at best inartful and at worst redundant”). But its purpose, at least, is straightforward: the act was designed to promote the timely cleanup of hazardous waste sites and to ensure that the costs of such cleanup efforts were borne by those responsible for the contamination. Burlington Northern, 556 U.S. at 602, 129 S.Ct. 1870 (citing Consol. Edison Co. of N.Y. v. UGI Util., Inc., 423 F.3d 90, 94 (2d Cir.2005)); Key Tronic Corp. v. United States, 511 U.S. 809, 819 n. 13, 114 S.Ct. 1960, 128 L.Ed.2d 797 (1994) (“CERCLA is designed to encourage private parties to assume the financial responsibility of cleanup by allowing them to seek recovery from others”). Relevant to this case, two CERCLA sections — 42 U.S.C. §§ 9607(a) and 9613(f) — afford rights of action to private parties seeking to recover expenses associated with cleaning up contaminated sites. Actions under § 9607(a) and § 9613(f) are governed by different statutes of limitation, and we must decide under which section the Trustees’ CERCLA claim falls before determining whether it is time-barred. 42 U.S.C. § 9607(a), the first of the two sections in question, is the “cost recovery” provision of CERCLA. It identifies four categories of potentially responsible parties relative to any instance of contamination based on their relationship to the contaminated site. See § 9607(a)(l)-(4). When a release or threatened release of hazardous substances occurs, the PRPs are strictly liable for “all costs of removal or remedial action incurred by the United States Government or a State or an Indian tribe not inconsistent with the national contingency plan[,]” § 9607(a)(4)(A), as well as for “any other necessary costs of response incurred by any other person consistent with the national contingency plan.” § 9607(a)(4)(B). The phrase “any other person,” as used in § 9607(a)(4)(B), has been read literally to mean any person other than the United States, a State, or an Indian tribe — in other words, any person other than the entities listed in sub-part (A). See United States v. Atl. Research Corp., 551 U.S. 128, 127 S.Ct. 2381, 168 L.Ed.2d 28 (2007). Thus, § 9607(a)(4)(B) grants one PRP the same rights as an innocent party to sue another PRP for cleanup costs incurred in a removal or remedial action. . Id. In such cases, the defendant’s liability — although strict — need not be joint and several. See Burlington Northern, 556 U.S. at 613-14, 129 S.Ct. 1870. Judicial apportionment is proper so long as the defendant can demonstrate that there is a reasonable basis for determining the contribution of each cause to a single harm. Id. (citing United States v. Chem-Dyne Corp., 572 F.Supp. 802, 810 (S.D.Ohio 1983); Restatement (Second) of Torts § 433A(l)(b), p. 434 (1963-1964)). 42 U.S.C. § 9613(f), on the other hand, is the “contribution” provision of CERCLA. Added to the statute by the Superfund Amendments and Reauthorization Act of 1986 (“SARA”), it creates two distinct rights to contribution, each subject to its own prerequisites. The first is codified at 42 U.S.C. § 9613(f)(1): Any person may seek contribution from any other person who is liable or potentially liable under section 9607(a) of this title, during or following any civil action under section 9606 of this title or under section 9607(a) of this title. (emphasis added). In Cooper Indus., Inc. v. Aviall Servs., Inc., 543 U.S. 157, 125 S.Ct. 577, 160 L.Ed.2d 548 (2004), the Supreme Court held that the italicized phrase has a limiting effect. “The natural meaning of this sentence is that the contribution may only be sought subject to the specified conditions!)]” Id. at 166,125 S.Ct. 577 (emphasis added). To read the clause more expansively would render the italicized phrase superfluous, which the Court was loathe to do. Id. (citing Hibbs v. Winn, 542 U.S. 88, 101, 124 S.Ct. 2276, 159 L.Ed.2d 172 (2004)). In short, “[t]here is no reason why congress would bother to specify conditions under which a person may bring a contribution claim, and at the same time allow contribution actions absent those conditions.” Id. After Cooper, a contribution action under 42 U.S.C. § 9613(f)(1) must be pre-dated by the filing of a civil action pursuant to § 9606 or § 9607(a). The second contribution right of action is codified at 42 U.S.C. § 9613(f)(3)(B): A person who has resolved its liability to the United States or a State for some or all of a response action or for some or all of the costs of such action in an administrative or judicially approved settlement may seek contribution from any person who is not party to a settlement referred to in paragraph (2). (emphasis added). As the Supreme Court did with respect to § 113(f)(1), supra, we read the italicized phrase as a limiting provision: a § 9613(f)(3)(B) contribution claim is only available to a person who has “resolved its liability ... in an administrative or judicially approved settlement.” See also Consol. Edison Co., 423 F.3d at 95 (holding that the resolution of CERCLA liability is a prerequisite to a § 9613(f)(3)(B) contribution action). To read the section as affording the same remedy to one who has not resolved his liability would be nonsensical, and it would render the limiting language superfluous. The Supreme Court has long insisted that result should be avoided wherever possible. See Cooper, 543 U.S. at 166, 125 S.Ct. 577; United States v. Nordic Village, Inc., 503 U.S. 30, 35-36, 112 S.Ct. 1011, 117 L.Ed.2d 181 (1992) (referencing the “settled rule that a statute must, if possible, be construed in such fashion that every word has some operative effect.”); Louisville & Nashville R. Co. v. Mottley, 219 U.S. 467, 475, 31 S.Ct. 265, 55 L.Ed. 297 (1911) (“We must have regard to all the words used by Congress, and as far as possible give effect to them.”). In summary, each CERCLA right of action carries with it its own statutory trigger, and each is a distinct remedy available to persons in different procedural circumstances. See Atl. Research, 551 U.S. at 139, 127 S.Ct. 2331 (citing Consol. Edison Co., 423 F.3d at 99); see also Niagara Mohawk Power Corp. v. Chevron USA, Inc., 596 F.3d 112, 122 (2d Cir.2010). Where a person has been subjected to a civil action under 42 U.S.C. §§ 9606 or 9607(a), he may attempt to recover his expenditures through a contribution suit under 42 U.S.C. § 9613(f)(1). Where a person has resolved his liability to the United States, or to a state, for some or all of a response action or for some or all of the costs of such action in an administrative or judicially approved settlement, he may attempt to recover his expenditures in a contribution' suit pursuant to 42 U.S.C. § 9613(f)(3)(B). If neither of those triggers has occurred, a plaintiff does not have a claim for contribution under CERCLA. That does not mean he has no remedy, however. Any time a person has incurred “necessary costs of response ... consistent with the national contingency plan[,]” CERCLA provides for a § 9607(a)(4)(B) cost recovery action. These are the plain terms of the statute. B. Classifying the Trustees’ CERCLA Claim The next step is to apply the statutory scheme to the facts to determine which sort of claim, or claims, the Trustees have advanced, and whether it is barred by the applicable statute of limitations. In Count I of the Complaint, the Trustees seek to recover the costs they incurred pursuant to the 1999 and 2002 AOCs. In order to determine which kind of CERCLA claim Count I states, we must take a closer look at the undisputed documentary evidence presented, particularly the AOCs themselves. In doing so, we find that the Trustees have stated a cost recovery claim under § 9607(a), but only with respect to costs incurred pursuant to the 2002 AOC. At this point, costs incurred pursuant to the 1999 AOC could only be recovered through a contribution claim, which is time-barred. 1. The 1999 AOC Under the 1999 AOC, the Non-Premium Respondents took on significant responsibilities. They agreed to undertake the EE/CA study of removal alternatives for Third Site, to develop and submit an EE/CA report to the EPA, and to settle and fund the Third Site Trust. They also agreed to reimburse the federal government for the EPA’s past response and oversight costs, for any future oversight costs incurred in conjunction with the EE/CA project, and for an amount certain to be expended by the Department of the Interior in addressing natural resource damages at Third Site. The 1999 AOC laid out deadlines for the Non-Premium Respondents to meet their obligations, and made clear that no release from CERCLA liability would occur until those obligations were met: Except as expressly provided in Section XIII (Covenant Not to Sue), nothing in this Order constitutes a satisfaction of or release from any claim or cause of action against the Respondents or any person not a party to this Order, for any liability such person may have under CERCLA, other statutes, or the common law, including but not limited to any claims of the United States for costs, damages and interest under Sections 106(a) or 107(a) or CERCLA, 42 - U.S.C. §§ 9606(a), 9607(a). The covenants not to sue referred to in the disclaimer above were expressly conditioned on the Respondents’ fulfillment of their obligations under the Order: Except as otherwise specifically provided in this Order, upon issuance of the [Notice of Completion], U.S. EPA covenants not to sue Respondents for judicial imposition of damages or civil penalties or to take administrative action against Respondents for any failure to perform actions agreed to in this Order[.] [I]n consideration and upon Respondents’ payment of [the EPA’s response costs], U.S. EPA covenants not to sue or take administrative action against Respondents under Section 107(a) of CERCLAL] And, most explicitly, as modified by the attached errata sheet: These covenants are conditioned upon the complete and satisfactory performance by Respondents of their obligations under this Order. Moreover, just as the EPA refused to give up its rights to sue the Respondents, the Respondents refused to consider the Order to be an admission of liability on their part: Respondents’ agreement to comply with and be bound by the terms of this Order and not to contest the basis or validity of this Order or its terms shall not constitute any admission of liability by any (or all) of the Respondents nor any admission by Respondents of the basis or validity of U.S. EPA’s findings, conclusions or determinations contained in this Order. Under the plain language of the AOC, with respect to the Non-Premium Respondents, the EPA’s covenants not to sue — and the accompanying release from CERCLA liability — -would take effect when they had seen the EE/CA project through to its completion and provided the Trust with sufficient funds to meet its monetary commitments pursuant to the AOC, and no sooner. It is undisputed that the Non-Premium Respondents did meet those obligations, as the EPA approved their performance of the 1999 AOC on October 24, 2000. a. The Trustees have a § 9613(f)(3)(B) contribution claim for costs incurred under the 1999 AOC. By the terms of the AOC, when the Non-Premium Respondents completed performance of their obligations under the 1999 AOC and obtained a notice of approval from the EPA, the conditional covenants not to sue contained therein went into effect. At that point, the Non-Premium Respondents, and by extension the Trust, had “resolved [their] liability to the United States ... for some or all of a response action or for some or all of the costs of such action” through an administrative settlement, thus satisfying the prerequisites for a contribution action pursuant to 42 U.S.C. § 9613(f)(3)(B). Specifically, the Trust had resolved its liability to the United States with respect to the execution of the EE/CA and with respect to the reimbursement of government response and oversight costs incurred prior to and in conjunction with the EE/CA project. As a result, they were entitled to recover the costs they incurred in accomplishing those tasks through a contribution action. Of course, the Trustees also incurred necessary costs of response consistent with the national contingency plan. They did not simply reimburse the EPA for a removal action it had already performed; they funded and executed the removal action themselves. In that sense, the trigger for a § 9607(a) cost recovery action was also met. This brings us to one of the questions raised in the briefs: are there any circumstances under which a plaintiff may bring both a cost recovery and a contribution claim under CERCLA? The Supreme Court left that possibility open in Atlantic Research: We do not suggest that §§ 107(a)(4)(B) and 113(f) have no overlap at all. Key Tronic Corp. v. United States, 511 U.S. 809, 816, 114 S.Ct. 1960, 128 L.Ed.2d 797 (1994) (stating the statutes provide “similar and somewhat overlapping remedies]”). For instance, we recognize that a PRP may sustain expenses pursuant to a consent decree following a suit under § 106 or § 107(a). See, e.g., United Technologies Corp. v. Browning-Ferris Industries, Inc., 33 F.3d 96, 97 (1st Cir.1994). In such a case, the PRP does not incur costs voluntarily but does not reimburse the costs of another party. We do not decide whether these compelled costs of response are recoverable under § 113(f), § 107(a), or both. 551 U.S. at 139 n. 6,127 S.Ct. 2331. Most circuits, after Atlantic Research, have not allowed a plaintiff to pursue a cost recovery claim when a contribution claim is available. See Solutia, Inc. v. McWane, Inc., 672 F.3d 1230, 1236-37 (11th Cir.2012); Morrison Enters., LLC v. Dravo Corp., 638 F.3d 594, 603 (8th Cir.2011); Lyondell Chem. Co. v. Occidental Chem. Corp., 608 F.3d 284, 291 n. 19 (5th Cir.2010) (acknowledging, and not disturbing, district court’s implicit decision that plaintiff could not pursue both remedies); Agere Sys., Inc. v. Advanced Envtl. Tech. Corp., 602 F.3d 204, 229 (3d Cir.2010); Niagara Mohawk Power Corp. v. Chevron U.S.A., Inc., 596 F.3d 112, 128 (2d Cir.2010); ITT Indus., Inc. v. BorgWamer, Inc., 506 F.3d 452, 458 (6th Cir.2007). Two justifications are usually given for reaching that conclusion. First, courts have noted that, despite its passing acknowledgment of a possible overlap in Atlantic Research, the Supreme Court has repeatedly emphasized the procedural “distinctness” of the CERCLA rights of action. See, e.g., 551 U.S. at 138, 127 S.Ct. 2331; Niagara Mohawk, 596 F.3d at 128; ITT Indus., 506 F.3d at 458. Second, some courts have concluded that permitting a party who has already resolved his own liability through a settlement to pursue a § 9607(a)(4)(B) action would allow him to exploit CERCLA’s “contribution bar” provision to shift full liability onto the target of his suit, a result antithetical to the purpose of the statute. See, e.g., Solutia, 672 F.3d at 1237; Agere Sys., Inc., 602 F.3d at 228-229. The “contribution bar” argument, although common in the case law, is based on a faulty premise. The argument is that a § 9607(a) cost recovery suit imposes joint and several liability on its target, whereas a contribution defendant only faces equitable apportionment. At the same time, pursuant to § 9613(f)(2), a party who has “resolved its liability to the United States or a State in an administrative or judicially approved settlement shall not be liable for claims for contribution regarding matters addressed in the settlement.” Several courts have concluded that allowing a party who has resolved its liability through settlement — and who thus meets the prerequisites for a § 9613(f)(3)(B) contribution action, as well as for protection under § 9613(f)(2) — to pursue a cost recovery action instead would allow that party to impose joint and several liability on a defendant without any fear of a counterclaim, due to the operation of § 9613(f)(2). Solutia, 672 F.3d at 1237; Agere Sys., Inc., 602 F.3d at 228-229. Theoretically, one PRP could shift full liability onto another PRP and escape all liability himself. Given that CERCLA is intended to distribute the costs of environmental correction among all of those who bear responsibility for an instance of contamination, see Burlington Northern, 556 U.S. at 602, 129 S.Ct. 1870, such gamesmanship seems inappropriate. The problem, of course, is that § 9607(a) does not always impose joint and several liability. Apportionment is proper on a cost recovery claim where there is a reasonable basis for determining the contribution of each cause to a single harm. Burlington Northern, 556 U.S. at 614, 129 S.Ct. 1870. Apportionment is likewise the remedy for a contribution claim. As a result, counterclaim or no counterclaim, there is not more risk that a defendant could be gamed into shouldering full liability, or more than his fair share, by a plaintiff with a § 9607(a) cost recovery action than by a plaintiff with a § 9613(f)(3)(B) contribution action. After Burlington Northern, the “contribution bar” argument is not persuasive. The other justification usually offered for limiting a plaintiff to one form of CERCLA action — the procedural distinctness of the remedies — is more compelling. As the Second Circuit has observed, “[t]o allow [a qualifying contribution plaintiff] to proceed under § 9607(a) would in effect nullify the SARA amendment and abrogate the requirements Congress placed on contribution claims under § 9613.” Niagara Mohawk, 596 F.3d at 128. “ ‘When Congress acts to amend a statute, [courts] presume it intends its amendment to have real and substantial effect.’ ” Id. (citing Stone v. INS, 514 U.S. 386, 397, 115 S.Ct. 1537, 131 L.Ed.2d 465 (1995)). We agree with the. sentiments expressed by the Second Circuit. Through SARA, Congress intentionally amended CERCLA to include express rights to contribution, subject to certain prerequisites. If § 9607(a) already provided the rights of action contemplated by the SARA amendments, then the amendments were just so many superfluous words. The canons of statutory construction counsel against any interpretation that leads to that result. See Hibbs, 542 U.S. at 101,124 S.Ct. 2276. In short, with respect to the 1999 AOC, the Trustees have a contribution action under § 9613(f)(3)(B). Although, giving the words their plain meaning, they have also incurred “necessary costs of response,” see § 9607(a)(4)(B), as is required to sustain a cost recovery action, we agree with our sister circuits that a plaintiff is limited to a contribution remedy when one is available. The next step is to determine whether the Trustees’ recovery, on a contribution theory, for costs incurred pursuant the 1999 AOC is time-barred. b. The Trustees are time-barred from recovering costs expended pursuant to the 1999 AOC. The statute of limitations for CERCLA contribution actions can be found at 42 U.S.C. § 9613(g)(3): . No action for contribution for any response costs or damages may be commenced more than 3 years after.— (A) the date of judgment in any action under this chapter for recovery of such costs or damages, or (B) the date of an administrative order under section 9622(g) of this title (relating to de minimis settlements) or 9622(h) of this title (relating to cost recovery settlements) or entry of a judicially approved settlement with respect to such costs or damages. The Bankerts argue that because the de minimis parties, also known as the Premium Respondents, settled out pursuant to § 9622(g), the three year limitations period began to run on the date the AOC was executed. The Trustees argue in response that it certainly did with respect to any claims that the de minimis parties might advance, but that none of the § 9613(g)(3) triggers have occurred with respect to their own claims. The Trustees argue that their claims fall within a “gap” in the statutory coverage, and that the gap should be filled with the limitations period applicable to actions under U.S.C. § 9607(a). An “initial action for the recovery of costs” under § 9607(a)' must be filed: (A) for a removal action, within 3 years after completion of the removal action, except that such cost recovery action must be brought within 6 years after a determination to grant a waiver under section 9604(c)(1)(C) of this title for continued response action; and (B) for a remedial action, within 6 years after initiation of physical on-site construction of the remedial action, except that, if the remedial action is initiated within 3 years after the completion of the removal action, costs incurred in the removal action may be recovered in the cost recovery action brought under this subparagraph. 42 U.S.C. §§ 9613(g)(2)(A)-(B). We need not resolve the “coverage gap” dispute with respect to the work performed under the 1999 AOC, because the outcome is the same either way. Assuming for the moment that we agree with the Trustees that the limitations period for a cost recovery action should apply, we note that an EE/CA is a “removal action.” See 40 C.F.R. § 300.415(b)(4)®. That means that § 9613(g)(2)(A) would apply to any attempt to recover the costs incurred in executing the EE/CA. Under that standard, the limitations period began running when the EE/CA project was completed in October of 2000. The Complaint in this case was filed on April 1, 2008, significantly more than three years later. Recovery is time-barred. Assuming, on the other hand, that we agree with the Bankerts and apply the statute of limitations for contribution actions, we would mark a start date for the limitations period on the date the AOC was executed. Pursuant to § 9613(g)(3)(B), the Trustees had three years from that date — in 1999 — in which to file an action. They missed the deadline by approximately six years; recovery is time-barred. Under either party’s theory, it is too late for the Trustees to recover the costs they incurred in carrying out the 1999 AOC. 2. The 2002 AOC After approving the work done under the 1999 AOC, the EPA issued an Enforcement Action Memorandum selecting a removal action and cleanup objectives from among the options detailed in the EE/CA. In November 2002, the parties entered into the second AOC to implement those solutions. The 2002 AOC included identieál conditional covenants not to sue and an identical disclaimer of liability on the part of the Respondents; its structure was largely parallel to that of the 1999 AOC. To the extent that the Trustees’ suit seeks to recover expenses arising out of their performance of the 2002 AOC, it is not a contribution action. The Trustees have been subjected to no civil action under §§ 9606 or 9607, so a contribution action under § 9613(f)(1) is unavailable. On the other hand, under the plain terms of the AOC, they could not have “resolved [their] liability to the United States ... for some or all of [the work performed under the 2002 AOC] or for some or all of the costs of [the work performed under the 2002 AOC] in an administrative ... settlement” at any time before satisfactory discharge of their obligations under the 2002 AOC. Since the work to be performed under the 2002 AOC was ongoing when this action was filed, and no notice of approval had issued which would trigger the conditional covenants not to sue, a contribution action under § 9613(f)(3)(B) is likewise unavailable. What the Trustees have done, with respect to the work called for by the 2002 AOC, is incur costs of response consistent with the national contingency plan, as is required to file a cost recovery action under § 9607(a). So, a plain reading of the statute and a sober look at the facts make it clear that a cost recovery action is available. Nonetheless, between the Bankerts and the EPA writing as amicus in support of rehearing, three different reasons have been advanced why this court should find that the Trustees are limited to a contribution action for costs incurred pursuant to the 2002 AOC. The first, championed primarily by the Bankerts, is that “compelled” costs incurred pursuant to an AOC must, as a matter of law, be recovered in a contribution action. The second, argued by both parties, is that the mere act of signing a settlement agreement amounts to a resolution of liability for purposes of the statute. The third argument is based on policy considerations and on the theory that withholding a contribution action until liability is actually resolved will discourage future polluters from settling early with the PRP. None of these arguments are factually or legally convincing, and they do not warrant a different result. a. The voluntary/compelled costs dichotomy The Bankerts’ first argument focuses on a distinction between voluntary and compelled costs: they claim that the Supreme Court drew a line in the sand in Atlantic Research and that in the current legal environment a cost recovery action is available only to plaintiffs who incurred costs “voluntarily”. “Compelled” costs, on the other hand, may only be recovered through a contribution action. Since the Trustees were “compelled” to clean up the site by the administrative settlement process, the Bankerts argue that they are limited to a contribution action. There are three significant problems with this argument. The first problem with the Bankerts’ argument is that it has no basis in the text of the source case. In Atlantic Research, the Court was asked to decide whether the phrase “any other person” in § 9607(a)(4)(B) provides PRPs, in addition to “innocent” parties, with a right to recover response costs from other PRPs. 551 U.S. at 131, 127 S.Ct. 2331. Arguing against that result, the United States suggested to the Court that allowing one PRP to maintain a § 9607(a) cost recovery action against another PRP would give it license to “cause shop” between an action for cost recovery and an action for contribution, choosing whichever section offered a perceived advantage under the circumstances of the case. In response to the government’s concern, the Court emphasized the procedural distinctness of the remedies. The Court contrasted a plaintiff who seeks to recover expenditures he himself incurred in cleaning up a site with a plaintiff who seeks to recover the cost of reimbursing another person’s expenditures pursuant to a settlement agreement or judgment. 551 U.S. at 139, 127 S.Ct. 2331. The former is a typical cost recovery claim, whereas the latter is a typical contribution claim under § 9613(f)(1). Id. Under the circumstances as hypothetically defined, the Court saw no room for choosing between the two: “[B]y reimbursing costs paid to other parties, the PRP has not incurred its own costs of response and therefore cannot recover under § 107(a). As a result, though eligible to seek contribution under § 113(f)(1), the PRP cannot simultaneously seek to recover the same expenses under § 107(a).” Id. The Court concluded that the government’s cause-shopping worries were thus unfounded. But before moving on, the Court recognized the limitations of its own conceptual illustration in a footnote, which we have quoted once already: We do not suggest that §§ 107(a)(4)(B) and 113(f) have no overlap at all. Key Tronic Corp. v. United States, 511 U.S. 809, 816, 114 S.Ct. 1960, 128 L.Ed.2d 797 (1994) (stating the statutes provide “similar and somewhat overlapping remedies]”). For instance, we recognize that a PRP may sustain expenses pursuant to a consent decree following a suit under § 106 or § 107(a). See, e.g., United Technologies Corp. v. Browning-Ferris Industries, Inc., 33 F.3d 96, 97 (1st Cir.1994). In such a case, the PRP does not incur costs voluntarily but does not reimburse the costs of another party. We do not decide whether these compelled costs of response are recoverable under § 113(f), § 107(a), or both. For our purposes, it suffices to demonstrate that costs incurred voluntarily are recoverable only by way of § 107(a)(4)(B), and costs of reimbursement to another person pursuant to a legal judgment or settlement are recoverable only under § 113(f). Thus, at a minimum, neither remedy swallows the other, contrary to the Government’s argument. 551 U.S. at 139 n. 6,127 S.Ct. 2331. The Bankerts conclude, based on the quoted footnote, that only parties who voluntarily incur response costs can bring an action for cost recovery under § 9607(a), and that parties who are “compelled” to incur response costs because of an enforcement action or a government settlement must proceed under § 9613(f) instead. But the Court said “costs incurred voluntarily are recoverable only by way of [§ 9607(a)(4)(B).]” Id. (emphasis added). That is not the same as saying that only voluntarily incurred costs are recoverable by way of § 9607(a)(4)(B). The latter implies the exclusion of costs of any other type; the former does not. The Supreme Court said, and meant, the former. In fact, the Court explicitly left open the possibility that parties who were “compelled” to incur costs — including parties who incurred costs subsequent to government settlements — might proceed under § 9607(a) nonetheless. Id. The second problem with the Bankerts’ position is that they have produced no legal authority in support of it. The cases they cite which did hold that PRPs who incurred cleanup costs under government settlements were bound to pursue a contribution claim did so because the statutory triggers for contribution claims were met, not because the costs were compelled as opposed to voluntary. See Niagara Mohawk, 596 F.3d 112 (holding that the plaintiff had a contribution claim under § 9613(f)(3)(B), because the plaintiff had resolved its CERCLA liability through an administrative settlement); Appleton Papers Inc. v. George A. Whiting Paper Co., 572 F.Supp.2d 1034, 1043 (E.D.Wis.2008) (dismissing a § 9607(a) cost recovery claim where a § 9613(f)(1) contribution claim was available to plaintiffs by virtue of a previous EPA lawsuit, and noting that “[d]espite the courts’ use of the terms ‘voluntary’ and ‘involuntary’ to distinguish between payments recoverable under § 107(a) and those recoverable under § 113(f), the operative principle appears to be that § 107(a) is available to recover payments only in cases where § 113(f) is not.”). The cases cited by the Bankerts with different outcomes simply reinforce the straight-forward application of the statutory scheme. See ITT Indus., Inc., 506 F.3d 452 (plaintiffs § 9613(f)(3)(B) claim was dismissed where the AOC did not resolve plaintiffs liability, as would be statutorily necessary to support a § 9613(f)(3)(B) action); Chitayat v. Vanderbilt Assocs., 702 F.Supp.2d 69 (E.D.N.Y.2010) (dismissing a § 9607(a) claim because, in the court’s eyes, the plaintiff never “incurred” costs, as is necessary for a cost recovery action): At least one case directly refutes the Bankerts’ argument that costs incurred pursuant to a settlement cannot be recovered under § 9607(a). In W.R. Grace & Co.Conn. v. Zotos Intern., Inc., 559 F.3d 85 (2d Cir.2009), a landfill owner brought an action to recover costs it incurred in the investigation and remediation of a contaminated landfill site pursuant to a government settlement agreement. Despite the existence of the settlement agreement, the court held that the plaintiff could recover its cleanup costs under § 9607(a) because neither contribution trigger had occurred. The settlement had not resolved CERCLA liability (§ 9613(f)(3)(B)) and no civil action had been filed (§ 9613(f)(1)). In short, not a single one of these cases treated the voluntary/ compelled costs dichotomy as dispositive. The third, and most obvious, problem with the Bankerts’ argument is that they are asking us to impose a requirement that appears nowhere in the statutory text. Imposing a requirement not evident on the face of the statute arguably violates fundamental rules of statutory construction. See E.I. DuPont de Nemours and Co. v. United States, 508 F.3d 126, 133 n. 5 (3d Cir.2007). As outlined in detail above, CERCLA does not ask whether a person incurs costs voluntarily or involuntarily. It asks whether a person incurred costs of response consistent with the national contingency plan, whether a person has previously been subjected to a civil action under § 9606 or § 9607(a), and so on. The Bankerts have advanced no persuasive reason, and we can think of none, why we would flatly disregard the terms of the statute and replace them with a new scheme of the Bankerts’ choosing, especially one with so little to recommend it in the case law. b. Equating signing a settlement agreement with the resolution of liability The Bankerts’ second argument is that the phrase “resolved its liability ... in an administrative or judicially approved settlement,]” as a statutory prerequisite to a contribution suit under § 9613(f)(3)(B), really just means “entered into an administrative or judicially approved settlement,” even where the settlement may. or may not lead to a resolution of liability depending on future events. In its amicus brief in support of rehearing, the EPA argued the same. The EPA summarized its argument as follows: Unlike “discharge,” “release,” or “satisfy,” the word “resolve” is not a term of art in contract law and is not defined in Black’s Law Dictionary. Congress therefore did not intend to require a PRP to completely extinguish its liability before obtaining contribution rights. Rather, Congress provided contribution rights to a PRP who “has resolved its liability ... in an administrative or judicially approved settlement.” 42 U.S.C. § 9613(f)(3)(B). Given that context, Congress meant that the settlement agreement needs to resolve a PRP’s liability, not that the release, covenant, or other liability-resolving term in the agreement must be effective for contribution rights to arise. In the AOCs, the settling PRPs promised to perform certain removal actions and EPA promised not to sue concerning those actions. The AOCs therefore are “settlement^]” that resolved the PRPs’ liability for response actions within the meaning of [§ 9613(f)(3)(B) ] and thus triggered contribution rights upon their effective dates. The argument, as stated in the passage above and explained in more detail throughout the EPA brief, is not legally persuasive. The EPA ignores traditional rules of statutory interpretation and jumps immediately from its observation that “resolve” is not a “term of art” to a discussion of House Reports and other evidence of legislative intent extrinsic to the statutory text. That path of analysis is not correct. When a statute itself does not define a term, “we construe the term ‘in accordance with its ordinary or natural meaning,’ a meaning which may be supplied by a dietionary.” Carmichael v. The Payment Center, Inc., 336 F.3d 636, 640 (7th Cir.2003) (quoting FDIC v. Meyer, 510 U.S. 471, 476, 114 S.Ct. 996, 127 L.Ed.2d 308 (1994)). This is because “the plain language of a statute is the best evidence of legislative intent.” Senne v. Village of Palatine, Ill., 695 F.3d at 597, 612 (7th Cir.2012) (Flaum, J., dissenting) (citing United States v. Clintwood Elkhorn Mining Co., 553 U.S. 1, 11, 128 S.Ct. 1511, 170 L.Ed.2d 392 (2008) (“The strong presumption that the plain language of the statute expresses congressional intent is rebutted only in rare and exceptional circumstances.”) (internal markup omitted)). Of course, while “[w]e frequently look to dictionaries to determine the plain meaning of words,” Sanders v. Jackson, 209 F.3d 998, 1000 (7th Cir.2000), we always do so with caution, sensitive to the need to consider the meaning of those words in context and to the reality that many words in our language are susceptible of multiple “ordinary or natural” meanings. United States v. Costello, 666 F.3d 1040, 1043-44 (7th Cir.2012); see also Trs. of Chicago Truck Drivers, Helpers, and Warehouse Workers Union (Indep.) Pension Fund v. Leaseway Transp. Co., 76 F.3d 824, 828 (7th Cir.1996). If the ordinary meaning of a word is totally ambiguous, then resort to legislative materials of the type referenced by the EPA is sometimes warranted. But even then, “where :.. the interpretation urged by [a party] is not supported by common usage, dictionary definition, or court decision, such interpretation cannot be upheld.” Torti v. United States, 249 F.2d 623, 625 (7th Cir.1957) (quoting Gellman v. United States, 235 F.2d 87, 93 (8th Cir.1956)). In short, it is what Congress says, not what Congress means to say, that becomes the law of the land. Statutory interpretation is therefore an exercise best grounded in the text of the statute itself. The statute at issue in this tase provides some context clues as to the meaning of the phrase “resolved its liability!.]” § 9613(f)(3)(B). First, “resolved” clearly acts as a verb and takes an object — “liability.” That eliminates the various dictionary definitions covering “resolve” used as an intransitive verb or as another part of speech entirely. A variety of potential meanings still remain,' but certain commonalities can be discerned. All of them seem to involve the concept of a conclusive determination of some kind. An issue which is “resolved” is an issue which is decided, determined, or settled — finished, with no need to revisit. This sense of the word is consistent with a common sense understanding of its role in the statutory text, and is also consistent with the way the term is regularly used by courts of law in unrelated contexts. See, e.g., Guzman v. City of Chicago, 689 F.3d 740, 745 (7th Cir.2012) (question of liability was “resolved” by the district court’s determination, at the summary judgment stage, that the defendant was liable); Shepherd v. C.I.R., 147 F.3d 633, 635 (7th Cir.1998) (suggesting that to “resolve” a taxpayer’s liability, in the refund suit context, means to make a final determination of the issue); Baylor Heating & Air Conditioning, Inc. v. Federated Mut. Ins. Co., 987 F.2d 415 (7th Cir.1993) (noting that plaintiffs “contested liability was resolved” when the Seventh Circuit conclusively found against him in an earlier declaratory judgment action); Deimer v. Cincinnati Sub-Zero Prods., Inc., 990 F.2d 342, 344 (7th Cir.1993) (characterizing a legal claim as “resolved” on summary judgment where it was conclusively decided). The cited cases suggest that, as a matter of common parlance, courts consider liability to be “resolved” when the issue of liability is decided, in whole or in part, in a manner that carries with it at least some degree of certainty and finality. Accordingly, having surveyed the statutory context, the dictionary definitions, and the common use of similar terms by the federal courts more generally, we believe the “ordinary or natural” meaning of the phrase “resolved its liability ... in an administrative or judicially approved settlement” is clear and unambiguous. To meet the statutory trigger for a contribution action under § 9613(f)(3)(B), the nature, extent, or amount of a PRP’s liability must be decided, determined, or settled, at least in part, by way of agreement with the EPA. As a matter of simple, observable fact, that did not happen here. Yes, the Non-Premium Respondents “settled” with the EPA. They agreed to perform certain actions in order to remedy an instance of environmental contamination. But they did not settle the issue of liability for that contamination — which is what the statute requires — at all. The parties do not need to take this panel’s word for it. They can refer to the language which they themselves chose to include in the 2002 AOC: Respondents’ agreement to comply with and be bound by the terms of this Order and not to contest the basis or validity of this Order or its terms shall not constitute any admission of liability by any (or all) of the Respondents nor any admission by Respondents of the basis or validity of U.S. EPA’s findings, conclusions or determinations contained in this Order. It is very difficult to say, in light of the quoted passage, that the agreement between the parties constituted a resolution of liability. The attempts by the EPA and the Bankerts to argue otherwise depend on the assertion that,“[i]n the AOCs, the settling PRPs promised to perform certain removal actions and EPA promised not to sue concerning those actions.” But while the Non-Premium Respondents did indeed promise to perform certain removal actions, the EPA only conditionally promised to release the Non-Premium Respondents from liability. The condition which had to be met was complete performance, as well as certification thereof. If the EPA’s covenant not to sue is the contemplated “resolution of liability” in this case — and the argument advanced by the EPA and the Bankerts seems to agree that it is — then, by the terms of the AOC itself, the resolution of liability would not occur until performance was complete, which is the first time at which the covenant would have any effect. In fact, the EPA expressly reserved its right to “seek[ ] legal or equitable relief to enforce the terms of [the] Order” at any time before those covenants went into effect. Of course, if the EPA had included an immediately effective promise not to sue as consideration for entering into the agreement, the situation would be different. That is exactly what occurred in RSR Corporation v. Commercial Metals Co., 496 F.3d 552 (6th Cir.2007). In that case, as a term of the AOC, “the United States agreed ‘not to sue or take administrative action’ that would impose additional liability on RSR and its co-defendants[.]” Id. at 554. As a result, all parties agreed that RSR had resolved its liability through settlement and was therefore entitled to a § 9613(f)(3)(B) contribution action. Id. at 556. The Sixth Circuit also agreed, reasoning that “RSR’s promise of future performance was the very consideration it gave in exchange for the United States’ covenant not to seek further damages. RSR and its co-defendants in other words resolved their liability to the United States by agreeing to assume all liability (vis-avis the United States) for future remedial actions.” Id. at 558 (emphasis original). The Bankerts and the EPA believe this panel’s reading of the statute conflicts with the Sixth Circuit’s decision in RSR Corporation. However, we — like the Sixth Circuit — simply read the statute as requiring that liability be “resolved.” Our result differs from the result reached by the Sixth Circuit in RSR Corporation not because we apply a contradictory rule of law, but because of the obvious and dispositive differences in the facts. In that case, the consent order contained an immediately effective release from liability. In this case, it did not. In fact, far from immediately resolving all liability, see 496 F.3d at 558, our AOC immediately resolved none. So, the consideration in RSR Corporation was an immediate release from liability; the consideration in this case was a conditional promise to release from liability if and when performance was completed. Given the nature of the statutory trigger, that distinction clearly warrants a different result — a reality which the Sixth Circuit itself has openly recognized. See, e.g., ITT Indus., Inc., 506 F.3d at 459-60 (finding that plaintiff had not “resolved its liability” for purposes of § 9613(f)(3)(B) contribution action when plaintiff “has not conceded the question of liability as part of its settlement with the EPA”). The same distinction differentiates this case from Dravo Corp. v. Zuber, 13 F.3d 1222 (8th Cir.1994). There is no circuit split here. In summary, the efforts of the Bankerts and the EPA to equate the resolution of liability, as a legal proposition, with the simple act of signing a settlement agreement are not persuasive. The ordinary and natural reading of the statute is that a contribution action becomes available when a PRP’s liability is resolved — as in decided or determined — through settlement. Whether or not liability is resolved through a settlement simply is not the sort of question which can or should be decided by universal rule. Instead, it requires a look at the terms of the settlement on a case-by-case basis. The parties to a settlement may choose to structure their contract so that liability is resolved immediately upon execution of the contract. See RSR Corporation, 496 F.3d 552; Dravo, 13 F.3d 1222. Or, the parties may choose to leave the question of liability open through the inclusion of reservations of rights, conditional covenants, and express disclaimers of liability. See, e.g., ITT Indus., Inc., 506 F.3d at 459-60 (finding that plaintiff had not “resolved its liability”