Full opinion text
MEMORANDUM OPINION PAUL W. GREENE, United States Chief Magistrate Judge. Before the court are motions to reconsider filed by defendants Huron Valley Steel Corporation; Walter Energy, Inc.; United States Pipe and Foundry Company, Inc.; McWane, Inc.; FMC Corporation; BEA Systems & Armaments, LP; DII Industries, LLC; MeadWestvaco Corporation; Phelps Dodge Industries, Inc.; Southern Tool LLC; and Scientific-Atlanta, Inc. (hereinafter the “Defendants”). (Docs. 542, 544, 546, 547, 548, 549, 550, 554, 558, & 581). The Defendants have moved for reconsideration of that portion of the court’s memorandum opinion and order of June 10, 2008 (Docs. 397 & 398) that denied the defendants’ motions for summary judgment on claims asserted by the plaintiffs, Solutia Inc. (“Solutia”) and Pharmacia Corporation (“Pharmacia”) (collectively “S/P”), to recover response costs under § 107(a)(4)(B) of the Comprehensive Environmental Response, Compensation, and Liability Act (“CERCLA”), 42 U.S.C. § 9607(a). The court held a hearing on the motions to reconsider on May 25, 2010. Upon consideration, the court concludes that the Defendants’ respective motions to reconsider are due to be granted. I. BACKGROUND A. PCB Contamination in Anniston This case is complex, in terms of its underlying facts, its litigation history, and the legal issues it presents. From 1929 to 1971, Monsanto Company (“Monsanto”) and its predecessors produced polychlorinated biphenyls (“PCBs”) at a plant approximately one mile west of downtown Anniston, Alabama, (the “Anniston Plant”). PCBs were widely used in industry for more than five decades because they are resistant to fire and are chemically inert, which means they do not readily react with other substances. These attributes made PCBs especially useful in safety fluids used to insulate and cool heavy duty electrical equipment, including transformers and capacitors. In the late 1960s, Monsanto learned that the same trait that made PCBs so attractive to industry — the fact that they do not react readily with other substances— also resulted in their persistence in the environment. (Amended Complaint (hereinafter “Complaint” or “Compl.”), Doc. 86, ¶¶ 12, 13). Further, as noted in the court’s prior summary judgment memorandum opinion, PCBs have been found to cause cancer, decreased fertility, still births, and birth defects in test animals. Environmental Defense Fund v. Environmental Protection Agency, 636 F.2d 1267, 1270 (D.C.Cir.1980).... The EPA has noted the “well-documented human health and environmental hazard of PCB exposure” and the “potential hazard of PCB exposure posed by the transportation of PCBs.” 40 C.F.R. § 761.20. Indeed, PCBs pose such health and environmental dangers that the Toxic Substances Control Act bans the manufacturing of PCBs in this country without a special exemption from the EPA. 15 U.S.C. §§ 2605(e)(3)(A) & (B). Dickerson, Inc. v. United States, 875 F.2d 1577, 1583 (11th Cir.1989). In 1997, Monsanto created Solutia in a spin-off transaction which now owns and operates the Anniston Plant. (Compl. ¶ 6). In 2000, Pharmacia was formed by the merger of Monsanto and Pharmacia & Upjohn, Inc. (Id. ¶ 5). B. The Removal Order In June 1999, the United States Environmental Protection Agency (“EPA”) began sampling activities to assess PCB contamination related to prior operations at the Anniston Plant. Pursuant to its authority under CERCLA, EPA entered into an Administrative Order on Consent with Solutia, docket no. 01-02-C, effective October 27, 2000, (the “2000 Solutia AOC”), under which Solutia agreed to perform additional sampling and PCB cleanup activities in Anniston. The 2000 Solutia AOC was superceded by a second Administrative Order on Consent between EPA and Solutia, docket no. CER-04-20023752, which was effective on October 5, 2001. That second AOC, referred to hereinafter as the “Removal Order” (Doc. 330-4, Exhibit 1C to Plaintiffs Response in Opposition to Settling Defendants’ Motion for Summary Judgment), generally provides for the performance of a “removal action” by Solutia and the reimbursement of oversight costs incurred by the United States in connection with contamination located on an area known as the “Anniston PCB Site” (Removal Order, § I), which is defined in the Removal Order as “consisting] of residential, commercial, and public properties located in and around Anniston, Calhoun County, Alabama that contain or may contain hazardous substances, including [PCB] impacted soil.” (Removal Order, § III, definition of “Site”). In outlining the work Solutia was to perform, the Removal Order acknowledged that the purposes of the “time critical removal order” it requires “are to determine the extent of PCBs, lead, and other hazardous substances” and “to conduct appropriate removal activities” in specific geographical areas designated as “Zones 1, 2, 3, 6 and ‘F’,” identified in an attached “Figure 1,” and as the “Oxford Lake Neighborhood (‘OLN’),” identified in an attached “Figure 2.” (collectively the “Removal Order Zones”). (Removal Order, § VI, ¶ 2.0). Under the Removal Order, Solutia was obligated to conduct surface soil sampling, as directed by EPA, at residential properties in the Removal Order Zones that had either not previously been sampled by EPA for PCBs or had undergone only limited data sampling. (Id., § VI, ¶¶ 2.0(a)). Under the Removal Order’s sampling regimen, Solutia was generally required to test for both PCBs and lead, notwithstanding that EPA had not determined that Solutia was a source of lead contamination in the Anniston area and that Solutia had expressly denied liability on that score. (Id., § VI, ¶ 2.0(h)). Regardless of the scope of Solutia’s sampling duties, however, the Removal Order required Solutia to take soil abatement measures based upon sampling results as they pertained only to the level of PCBs, not lead. More particularly, one of Solutia’s primary abatement duties was to “conduct a removal response” at properties within the Removal Order Zones that prior or subsequent sampling either by EPA or by Solutia under the Removal Order indicated PCBs in surface soils at a concentration of 10 milligrams per kilogram (“mg/kg”) or greater. (Id., § VI, ¶¶ 2.0(b), (c), & (d)). EPA generally covenanted in the Removal Order that, upon issuance of a notice acknowledging that Solutia had fulfilled its obligations thereunder, EPA would not sue Solutia for damages or civil penalties or take administrative action for any failure to perform. (Id., § XIV). In addition, the parties acknowledged that Solutia was entitled to protection from contribution actions or claims to the extent provided by §§ 113(f)(2) and 122(h)(4). C. The Enforcement Case • On March 25, 2002, the United States filed a CERCLA enforcement action in this court against both Solutia and Pharmacia for their activities and liability associated with the “Anniston PCB Site,” alleged in the complaint to “consistí] of [S/P]’s plant site, [and]' residential and commercial properties located in and around Anniston, Alabama, that are suspected of containing PCB-contaminated soil and sediments.” (United States v. Pharmacia Corp. et al., 1:02-cv-749-PWG (N.D.Ala.) (hereinafter the “Enforcement Case” or “Enf. Case”), Doc. 1 (“Enforcement Case Complaint” or “Enf. Case Compl”) ¶¶1, 9). Invoking CERCLA §§ 104, 106, 107, 113 and 122, the government sought three types of relief. First, the government asked for an injunction requiring S/P to perform certain recovery actions, including a Remedial Investigation and Feasibility Study (“RI/FS”). (Enf. Case Compl., “First Claim for Relief’ ¶¶ 21-24). Second, the government claimed entitlement to reimbursement for its own costs of response under § 107(a)(4)(A). (Id., “Second Claim for Relief’ ¶¶ 25-29). Finally, the government sought a declaratory judgment on S/P’s liability for response costs that would be binding on any subsequent action or actions to recover further response costs or damages, as authorized under § 113(g)(2), 42 U.S.C. § 9613(g)(2). (Enf. Case Compl. “Prayer for Relief’ ¶ 1). Contemporaneously with the filing of the Enforcement Case Complaint, the United States submitted a proposed Partial Consent Decree entered into by the parties that would, if approved, settle certain claims identified in the Enforcement Case Complaint. (Enf. Case, Doc. 2); see also § 122(d)(1), 42 U.S.C. § 9622(d)(1). On October 23, 2002, after a notice and comment period on the proposed Partial Consent Decree, see § 122(d)(2), 42 U.S.C. § 9622(d)(2), the parties filed a proposed Revised Partial Consent Decree with appendices (hereinafter the “PCD,” Enf. Case Doc. 72) and an accompanying motion for its entry. (Enf. Case Docs. 13 & 14). Ultimately, the court, acting through then-Chief Judge U.W. Clemon, approved and entered the PCD on August 4, 2003. (Enf. Case Docs. 71 & 72). In setting out S/P’s cleanup “commitments,” the PCD incorporated and memorialized joint and several obligations of S/P to finance and perform three categories of ‘Work” set forth in other documents attached as appendices to the PCD itself. (See PCD, § VI, ¶6). One category of such Work” was the “Removal Order Work,” which arose from the Removal Order, discussed above. (PCD, § V, ¶¶ 6, 8; see also id., § IV, ¶¶ AA, BB). The other two categories were designated as “NTC [Non-time Critical] Removal Work” and “RI/FS Work.” (Id., § V, ¶ 6). They respectively arose from documents captioned, naturally enough, a “NTC [Non-time Critical] Removal Agreement” (Doc. 330-8, Exhibit 1G to Plaintiffs’ Response in Opposition to Settling Defendants’ Motion for Summary Judgment, hereinafter “NTC Removal Agreement” or “NTC Rem. Agmt.”; PCD, § V, ¶ 6, 9; id., § IV, ¶¶ P, Q), and an “RI/FS Agreement” (Doc. 330-2, Exhibit 1A to Plaintiffs’ Response in Opposition to Settling Defendants’ Motion for Summary Judgment, hereinafter “RI/FS Agreement” or “RI/FS Agmt.”) and its implementing “Statement of Work” (Doc. 330-3, Exhibit IB to Plaintiffs’ Response in Opposition to Settling Defendants’ Motion for Summary Judgment hereinafter “RI/FS SOW”). (See PCD, §. V, ¶¶ 6, 9; id., § IV, ¶¶ CC, DD, HH). The NTC Removal Agreement and the RI/FS Agreement were administrative settlement agreements between EPA and S/P that were signed in October 2002, at or about the same time that the parties signed the PCD. (See NTC Rem. Agmt. at pp. 31-32; RI/FS Agmt. at pp. 36-38; PCD at pp. 26-29). Both of those agreements were effective upon the court’s entry of the PCD. (NTC Rem. Agmt. at § XXI; RI/FS Agmt. at § XXIII). The area of contamination that was the principal subject of the PCD, the NTC Removal Agreement, and the RI/FS Agreement was stated, as in the Removal Order, to be the “Anniston PCB Site.” However, while the PCD, the NTC Removal Agreement, and the RI/FS Agreement all contain the same definition of the “Anniston PCB Site,” that definition is different from that which appears in the Removal Order, which is, in turn, also somewhat different from the term as used in the Enforcement Case Complaint, which are set forth above. Specifically, the PCD, the NTC Removal Agreement, and the RI/FS Agreement define the “Anniston PCB Site” as consisting] of the area where hazardous substances, including PCBs associated with releases or discharges as a result of the operations, including waste disposal, of the Anniston plant by Solutia, Inc., Monsanto Company, and their predecessors have come to be located. The [Anniston PCB] Site includes, but is not limited to, the area covered by the RCRA Permit [associated with the Anniston Plant]. (PCD, § IV, ¶ FF; NTC Rem. Agmt, § III, definition of “Site”; RI/FS Agmt, § IV, FF (footnote added)). Further, while the Removal Order references only a single, broadly defined “Anniston PCB Site,” the PCD, the NTC Removal Agreement, and the RI/FS Agreement acknowledge a second area of contamination known as the “Anniston Lead Site.” The PCD, the NTC Removal Agreement, and the RI/FS Agreement each define the Anniston Lead Site as “consisting] of the area where lead and other commingled hazardous substances, including PCBs, associated with the historical and ongoing industrial operations in and around Anniston, Alabama have come to be located.” (PCD, § IV, ¶ B; NTC Rem. Agmt, § III, definition of “Anniston Lead Site”; RI/FS Agmt, § IV, B). The United States covenanted in the PCD not to sue S/P or take any administrative action against them for performance of the Removal Work, RI/FS Work, or NTC Removal Order Work or for recovery of certain response costs, with such covenant taking effect upon EPA’s approval of a certification of completion pursuant to the RI/FS Agreement. (PCD, § X, ¶ 30). Likewise, the PCD makes clear the parties’ contemplation that the PCD extended protection to S/P from CERCLA contribution liability “for matters addressed in [the PCD],” pursuant to § 113(f)(2). (PCD, § XII, ¶ 39). By contrast, the government reserved all rights against S/P with regard to liability for the Anniston Lead Site (id., ¶ 30(j)), and both the government and S/P “expressly reserve[d] any and all rights (including, but not limited to, any right to contribution), defenses, claims, demands, and causes of action which each Party may have with respect to any matter, transaction, or occurrence relating in any way to the [Anniston PCB Site] and/or the Anniston Lead Site against any person not a Party hereto.” (PCD, § XII, ¶ 38). Under the NTC Removal Agreement, S/P assumed a number of additional sampling and removal duties beyond those contained in the Removal Order. These included submission of a “Supplemental Sampling Plan” that would require S/P to conduct composite surface soil sampling, “as directed by EPA, at residential properties that have not previously had composite sampling.” (NTC Rem. Agmt., § VI, ¶ 2.0(c)). Further, while Solutia’s soil removal obligations under the Removal Order were linked to a surface soil PCB concentration level of 10 mg/kg or greater, the NTC Removal Agreement indicated that it would likely implement a substantially lower threshold that would require S/P to conduct soil removal “for any property (including properties that are not within the Zones covered by the Removal Order)” (NTC Rem. Agmt., § VI, ¶ 2.0(e)), with a surface soil PCB concentration at or above 1 part per million (“ppm”) and at or above 10 ppm for soils below a depth of 12 inches, as disclosed by composite sampling done pursuant to the 2000 Solutia AOC, the Removal Order, the NTC Removal Order, or by EPA. (Id., § I at p. 2; id. § VI, ¶¶ 2.0(a), (e), (f), (h); Streamlined Risk Evaluation for Residential Areas, Doc. 330-9, Exhibit 1H to Plaintiffs’ Response in Opposition to Settling Defendants’ Motion for Summary Judgment, at 7). It is undisputed at this time that the 1 ppm PCB standard was adopted as the trigger for S/P’s soil removal obligations under the NTC Removal Agreement. The NTC Removal Agreement expressly recognized that there might be properties requiring a removal action by S/P because sampling showed they met the 1 ppm threshold for PCBs but also had lead contamination greater than 400 ppm. (NTC Rem. Agmt., § VI, ¶ 2.0(h)(4)). Such properties, the parties acknowledged, would “also [be] part of the Anniston Lead Site.” (Id, § I at p. 3). As in the Removal Order, S/P denied responsibility for lead contamination in Anniston, and EPA acknowledged that it had not made a determination as to whether S/P was a source of such contamination. (Id; id. § V, ¶ 8). Nonetheless, as to those dual contamination properties, S/P agreed to conduct depth sampling to determine the vertical extent of lead contamination, and if there was lead contamination greater than 400 ppm below a depth of 12 inches that would not be removed by the PCB removal action, S/P was required to notify EPA and “coordinate the PCB removal pursuant to [the] NTC Removal Agreement with any lead removal EPA determines is necessary.” (NTC Rem. Agmt., § VI, ¶ 2.0(h)(4)). EPA recognized, however, that if S/P were to “remove soil from any property having lead in excess of 400 ppm from a residential property pursuant to [the NTC Removal Agreement], ... [S/P] may seek contribution for the costs of such removal from PRPs at the Anniston Lead Site and any other parties who may be liable.” (Id, § I at 3). D. The Instant Action for Cost Recovery and Contribution On June 5, 2003, S/P filed this action. (Doc. 1). In its now-governing first amended complaint, S/P brought claims against a number of parties, including the remaining Defendants, alleging that these parties are liable under CERCLA. (Id; Compl., Doc. 86). In Count I, S/P asserted claims for contribution under § 113(f) with respect to cleanup activities they financed and performed at both the Anniston Lead Site and the Anniston PCB Site. (Compl., Count I, ¶¶ 330-339). In connection with these claims, S/P alleged that “Solutia, on its own behalf and on behalf of Pharmacia,” incurred response costs within the meaning of § 107(a) and § 101(25), 42 U.S.C. §§ 9601(25), “in connection with work performed under various state and federal orders” at the Anniston PCB Site and the Anniston Lead Site. (Id. ¶ 334; see also id, ¶ 22 (“Pursuant to the [2000 Solutia AOC, the Removal Order, and the PCD], Solutia and Pharmacia, without admitting liability, agreed to take over sampling for ... EPA in areas covered by the Orders, and to clean up contaminated properties in Anniston by removing contaminated foundry sand, fluff, and other contaminated waste All material, and replacing it with clean fill.”) S/P further maintained that each of the Defendants was a PRP under § 107(a) because they had released hazardous substances at both the Anniston PCB and Lead Sites. (Compl. ¶¶ 332, 338). As a result, S/P contended that they “are entitled to contribution from each the Defendants with respect to all response costs incurred by [S/P], or to be incurred by [S/P], including interest, in performing response activities pursuant to the federal and state orders at the Anniston PCB and Lead Sites.” (Compl. ¶ 338). In Count II, S/P sought to assert claims for “cost recovery” pursuant to § 107(a) with respect to the Anniston Lead Site only. (Id., Count Two, ¶¶ 340-349. Such claims were based upon the same allegations underlying the contribution claims asserted in Count I (see id.), plus an assertion by S/P that they did not contribute hazardous material to the Anniston Lead Site. (Id. ¶ 345). In the prayer for relief, S/P demanded a judgment allowing them to recoup from the Defendants S/P’s response costs incurred to date, including investigatory costs, legal fees, and interest. (Id., Prayer for Relief, ¶¶ (a)(b)). Finally, S/P sought a declaratory judgment holding the Defendants liable, as an equitable share or jointly and severally, for response costs that will be incurred by S/P in the future. (Id., ¶¶ (c)-(d)). E. The Foundry AOC In early May 2005, as this litigation was underway, and 21 months after Judge U.W. Clemon approved the PCD in the Enforcement Case, EPA entered into an Administrative Agreement and Order on Consent with a number of parties identified collectively as the Foothills Community Partnership (the “Partnership”). (See Doc. 296, the “Foundry AOC”, at § I, p. 3). Under that administrative agreement, hereinafter referred to as the “Foundry AOC,” with the exception of Southern Tool LLC (“Southern Tool”) and Scientific-Atlanta, Inc. (“Scientific-Atlanta”), all of the Defendants now remaining in this action and moving for reconsideration (the “Settling Defendants”) were members of the Partnership. (Id.) The Partnership’s primary undertakings pursuant to the Foundry AOC included reimbursement of $3.25 million to EPA for its past response costs; sampling and soil removal at residential and certain other types of properties, mostly within three designated geographic areas in and around Anniston identified as Zones A, B, and C, where sampling revealed soil lead concentration of at least 400 ppm; and reimbursing EPA for future costs it would incur overseeing the Partnership’s work. (Foundry AOC, § I, ¶ 1). With respect to soil removal obligations, the Foundry AOC expressly contemplated that some covered properties would have “commingled” soil contamination, with lead concentration of at least 400 ppm and PCB concentration of at least 1 ppm. (Foundry AOC, § III, ¶ 8(h)). In such cases, the Partnership was generally required to conduct soil removal efforts on such properties when located in Zones A and B (id., § VIII, ¶¶ 16(a), (b)(iii), (c)(iii)), but not when located in Zone C, except for certain specifically identified properties, (id., § VIII, ¶¶ 16(a)(1), (d)(ii)). The Foundry AOC also recognized that the Partnership members might potentially be required later to assume certain sampling and removal obligations with respect to a fourth area designated as “Zone D.” (See id., § III, ¶8(LI)-, id., § VIII, ¶ 16(e); id., § XX). In exchange for agreeing to perform these and other specified obligations, the Foundry AOC provided that members of the Partnership, including the Settling Defendants, had resolved their CERCLA liability to the United States and were entitled to protection from contribution claims, in relation to two areas, identified as the “Anniston Lead Site” and the “Anniston PCB Site.” (Foundry AOC, § XXIII, ¶ 74). While those same two sites were also referenced in the PCD, the NTC Removal Agreement, and the RI/FS Agreement between the government and S/P, the terms were defined differently when they appeared later in the Foundry AOC. Namely, the Foundry AOC defined the “Anniston PCB Site” as “the areas where PCBs associated with releases from the Anniston Industrial Operations, have come to be located” (id., § III, ¶ e) and the “Anniston Lead Site” as “the areas where lead associated with releases from the Anniston Industrial Operations has (sic) come to be located.” (Id., § III, 1fbb). The term “Anniston Industrial Operations,” in turn, encompassed a list identifying twenty-three industrial business locations throughout Anniston, including a host of current or former pipe, foundry, and machine works, including those operated by members of the Partnership or their predecessors, as well as the Anniston Plant of S/P. (See id., § III, ¶ d; id., “Appendix 1,” Doc. 296-2 at p. 6-9). Further, based upon EPA’s determination “that the quantity and/or toxic effects of the hazardous substances contributed by [the members of the Partnership] to the Anniston PCB Site is minimal in comparison to other hazardous substances at the Anniston PCB Site, particularly PCBs contributed by [S/P] or their predecessors,” Foundry AOC expressly recites that it constitutes a de minimis settlement under § 122(g), 42 U.S.C. § 9622(g), with respect to the Anniston PCB Site. (Foundry AOC, § V, ¶ g). Shortly after the parties to the Foundry AOC had signed it, the Settling Defendants filed motions in this case for protective orders and to stay discovery, contending that S/P’s claims against them would be precluded by the contribution protection granted by the Foundry AOC, once it took effect. (See Docs. 193-196). Simultaneously, S/P filed a motion in the Enforcement Case seeking an order from Judge Clemon holding the United States in contempt for allegedly violating terms of the PCD and prior court orders by negotiating and executing the Foundry AOC. (Enf. Case Doc. 137). Judge Clemon entered an order in which he recognized that “[S/P] would not have agreed to the [PCD] in the absence of a clause preserving their right to contribution from other [PRPs] for contamination of the Anniston PCB Site” and that the court, in approving the PCD, had similarly understood it to preserve such rights. (Enf. Case Doc. 144 at 1-2). In Judge demon’s view, however, the proposed Foundry AOC “apparently [would] have the likely effect of nullifying the Defendants’ rights of contribution against the named defendants in Solutia v. McWane.” (Id. at 2). Based on Judge demon’s determination that there is “indubitably a dispute concerning the meaning of the contribution provisions of the [PCD],” he ordered the United States and S/P to proceed with the dispute resolution procedures set forth in § VIII of the PCD and enjoined the United States from taking further action to approve or implement the proposed Foundry AOC for 30 days. (Id. at 2-3). After the United States filed a request for “clarification” of that order, Judge Clemon issued another, dated June 30, 2005. (Enf. Case Doc. 152). In that brief order, Judge Clemon denied the United States’ motion for contempt sanctions. (Id. at 1). He added, however, that the “Government’s effort to foreclose [S/ P]’s contribution rights” through the proposed Foundry AOC was “in effect a repudiation of the [PCD]” and that the United States had indicated that “any further dispute resolution, mediation, arbitration, or the like [over the contribution issue] is moot at this point.” (Id. at 2). The order then concluded: “Given the repudiation efforts by the United States and the impasse at which the parties find themselves, upon Motion by [S/P], this Court will suspend [S/P]’s obligations under the [PCD].” (Id.) At no point thereafter did S/P file a motion requesting such relief. Ultimately, the Foundry AOC went through public notice and comment and became effective on January 17, 2006. F. The Stipulation “Clarifying” the PCD By July 2006, S/P and EPA were engaged in a dispute over the nature and scope of certain of S/P’s obligations under the PCD. At that time, S/P and the United States settled such disagreement by entering into a “Stipulation and Agreement,” which by its terms “clarifies” S/P’s obligations under the PCD. (Doc. 545-2; Enf. Case Doc. 157-1, (the “Stipulation” or “Stip.”) at 1). Pursuant to the Stipulation, S/P agreed that it would be generally required to clean up all yards within Zones A and B, as defined in the Foundry AOC, where sampling by the Partnership or EPA under the Foundry AOC or by S/P disclosed surface soil PCB concentration of at least 1 ppm but that did not have surface soil lead concentration of 400 ppm or greater. (Stip., ¶¶ 8, 11). The Stipulation further provided that EPA could require S/P to perform sampling at certain other properties within Zone B and to clean up yards on those properties where such sampling showed soil PCB concentrations greater than or equal to 1 ppm, regardless of the levels of lead found there. (Id. ¶¶ 15, 16). Under the Stipulation, S/P also agreed to conduct additional sampling in Zones C and D, as defined in the Foundry AOC. (Id., ¶¶ 18, 19). In Zone C, S/P would also clean up any yards that had PCB concentration of 1 ppm or greater, regardless of the level of lead contamination (id., ¶ 18), while in Zone D, S/P would “clean up all yards that contain surface soil PCB concentrations greater than or equal to 1 ppm and/or surface soil lead concentrations greater than or equal to 400 ppm.” (Id., ¶ 19). The parties further agreed that except for the RI/FS Agreement and its implementing SOW, the PCD, the Removal Order and the NTC Removal Order “do not extend to any properties located outside of Zones A, B, C, and D.” (Id., ¶ 20). Finally, S/P also expressly waived their right, afforded by Judge demon’s order of June 30, 2005, to seek the suspension of their obligations under the PCD. (Id., ¶ 27). On July 18, 2006, the Stipulation was filed as an exhibit to a special masters’ status report in the Enforcement Case, which was still being overseen by Judge Clemon,(Enf. Case Doc. 157). G. The Defendants’ Motions for Summary Judgment Meanwhile, after the Foundry AOC became effective in January 2006, the Settling Defendants moved for summary judgment on all claims S/P brought against them in this action, whether characterized as seeking cost recovery under or contribution under CERCLA. (Doc. 295). Later, the other two Defendants, i.e., Southern Tool and Scientifie-Atlanta (the “Non-Settling Defendants”), also moved for summary judgment, but only as to the claims against them for cost recovery. (Docs. 355, 356). On June 10, 2008, the undersigned entered an order resolving the motions, granting in part and denying in part the Settling Defendants’ motion, while denying those of the Non-Settling Defendants. (Doc. 398, “June 2008 Summary Judgment Order” or “June 2008 Summ. J. Order”). In an accompanying memorandum opinion, the court concluded that the Settling Defendants were entitled to summary judgment on the § 113(f) contribution claims because they were precluded under §§ 113(f)(2) and 122(g)(5) by the Foundry AOC. (Doc. 397, the “June 2008 Summary Judgment Memorandum” or “June 2008 Summ. J. Mem.,” at 22-28). However, the court ruled that S/P were entitled to proceed against all Defendants on claims seeking cost recovery under § 107(a) relative to the Anniston Lead Site. (Id at 15-22). The court’s reasons for denying summary judgment on the cost recovery claims were basically two-fold. The first was based upon its resolution of a legal issue of statutory interpretation, in which the court concluded that the cost recovery remedy embodied in § 107(a) is generally available to any party that has itself financed cleanup efforts and is thus not limited, as the Defendants had argued, only to non-PRPs, “innocent” parties, or to those that have performed a cleanup “voluntarily,” ie., without having been compelled to do so by judicial or administrative governmental action. (June 2008 Summ. J. Mem. at 16-22). Because S/P had undisputedly incurred costs directly financing and performing cleanup work, the court explained, it could pursue cost recovery claims under § 107(a), even if their cleanup efforts were undertaken pursuant to, and were thus “compelled” by, the PCD. The second reason for the denial of summary judgment on the cost recovery claims was that, even assuming that a party cannot, as a matter of law, employ § 107(a) to recoup compelled cleanup costs, the record supported that, as a factual matter, at least some of the costs that S/P had incurred on the Anniston Lead Site were not, in fact, compelled because, the court determined, the terms of the PCD did not impose obligations upon S/P vis-á-vis the Anniston Lead Site. (Id at 17-18). In addition, the court further addressed the compulsion issue by noting that Judge demon’s June 30, 2005 order in the Enforcement Case had at least ambiguously suggested that he might have suspended S/P’s obligations under the PCD, which have effectively rendered voluntary any subsequent response expenditures by S/P. (Id at 18). At a hearing in September 2009 on another matter, an attorney for the United States, a nonparty in this case, verbally asked the court to reconsider its June 2008 summary judgment order to the extent it had declined to dismiss the § 107(a) claims for cost recovery. (Doc. 541 at 59). In support, the United States asserted that a number of cases decided since the Supreme Court’s decision in United States v. Atlantic Research Corp., 551 U.S. 128, 127 S.Ct. 2331, 168 L.Ed.2d 28 (2007), were asserted to be contrary to this court’s summary judgment ruling on the § 107 claims and also that the terms of the Stipulation, which had not been presented to the court when it ruled in June 2008, allegedly demonstrated that the PCD (1) had compelled the response costs for which S/P was seeking recovery under § 107 and (2) had not been suspended by Judge Clemon. (Id. at 56-60, 62-64). While the court declined to reconsider its summary judgment order at the time for a number of reasons, including that the United States had no standing to seek such reconsideration and no party in the case done so, the court intimated its belief that it was authorized to revisit its summary judgment ruling and that it was “not truly adverse” to doing so. (Id at 66-67). With that door left ajar, the Defendants obliged with motions to reconsider. (Docs. 542, 544, 546, 547, 548, 549, 550, 551, 554, 557, 558, & 581). In their motions, the Settling Defendants contend that they are entitled to summary judgment on the § 107(a) claims as well as on the § 113(f) claims, which would result in their dismissal as parties. The Non-Settling Defendants, by contrast, acknowledge that they are potentially subject to claims for contribution under § 113(f), but they argue that such claims are S/P’s exclusive remedy against them. II. DISCUSSION A. Timeliness of the Motions to Reconsider As a threshold matter, S/P argues that the court cannot consider the motions to reconsider on the theory that they are untimely. (Doc. 604, Plaintiffs’ Supplemental Brief and Memorandum in Opposition to Defendants’ Motions to Reconsider (“S/P Supp. Brief in Opp. to Reconsid.”), at 3). S/P points out that the defendants have invoked Rule 60(b) of the Federal Rules of Civil Procedure as the basis for their motions to reconsider and that such motions must be filed within a “reasonable time” under Rule 60(c), Fed.R.Civ.P. Because there was a delay of approximately 18 months between the court’s June 2008 summary judgment decision and the filing of the first motion to reconsider in December 2009, S/P claims that the motions come too late. (S/P Supp. Brief in Opp. to Reconsid. at 3). The timing of the motions is not material. Time limits applicable to Rule 60(b) motions do not apply to the defendants’ motions to reconsider. Notwithstanding any reliance by the defendants on Rule 60(b), that rule does not authorize or govern motions requesting a court to revisit non-final, interlocutory orders, including rulings that deny summary judgment in whole or in part. See Bon Air Hotel, Inc. v. Time, Inc., 426 F.2d 858, 862 (5th Cir. 1970); Zimzores v. Veterans Admin., 778 F.2d 264, 266 (5th Cir.1985); Nicholson v. City of Daphne [Civ. No. 95-W-1031-N], 2009 WL 2045152, *2 (S.D.Ala. July 7, 2009) (unpublished). Rather, a district court retains discretionary authority to revisit such interlocutory orders at any time prior to final judgment. See Harper v. Lawrence County, Ala., 592 F.3d 1227,-1231 (11th Cir.2010); Aldana v. Del Monte Fresh Produce, N.A., Inc., 578 F.3d 1283,-1289 (11th Cir.2009); Hardin v. Hayes, 52 F.3d 934, 938 (11th Cir.1995). B. Legal Standards Applicable to Motions to Reconsider In a second procedural argument, S/P also assert that the court may not, or at least should not, revisit its summary judgment order because, S/P contends, the legal standards or prerequisites for a motion to reconsider have not been met. (S/P Supp. Brief in Opp. to Reconsid. at 2-3). S/P maintains that “[ojnly three grounds justify reconsideration: (1) an intervening change in controlling law; (2) the availability of new evidence; or (3) the need to correct clear error or manifest injustice.” (Id. at 2, citing Mitchell v. Crowell, 975 F.Supp. 1440, 1442 (N.D.Ala.1997)). S/P urges that none of these circumstances are present. S/P’s arguments fail to establish that it is improper for the court to entertain the defendants’ motions to revisit the June 2008 summary judgment order. It is not disputed that in general a finding that there exists at least one of the circumstances cited by S/P from Mitchell before reconsidering an earlier order represents a sound prudential limitation on the propriety of revisiting interlocutory rulings. Even so, there are at least two grounds why reconsideration of summary judgment is warranted. The first is the availability of additional evidence, which is the second Mitchell circumstance. The court’s June 2008 summary judgment ruling was based in part on an ambiguity in Judge demon’s June 30, 2005 order that potentially rendered it subject to the interpretation that it operated to suspend S/P’s obligations under the PCD, supporting that S/P’s clean up efforts thereafter were voluntarily in the sense that they were no longer compelled by the PCD. It is now crystal clear, however, from the Stipulation, S/P’s briefing on the motions to reconsider, and from a declaration attached to the latter, none of which was before the undersigned in June 2008, that Judge demon’s order did not itself suspend S/P’s obligations under the PCD, that S/P never moved for such relief, and that S/P is not making any claim to the contrary. (Stip. ¶ 27; S/P Supp. Brief in Opp. to Reconsid. at 32; Declaration of George Frampton, Jr., Exhibit B to S/P Supp. Brief in Opp. to Reconsid., ¶¶ 11-12). In addition, the Stipulation, which by its terms “clarifies” the nature and scope of S/P’s duties under the PCD and the administrative orders referenced therein, constitutes new evidence on the broader factual question of whether S/P’s particular response activities in Anniston were compelled. The second reason justifying reconsideration is the existence of additional legal authority from a number of federal courts since this court issued its June 2008 decision. It is true that there has not been a “controlling” case from the Supreme Court or the Eleventh Circuit on the primary issue raised by the motions to reconsider: the relationship between CERCLA’s cost recovery and contribution causes of action. That relationship is decidedly unsettled, however, as discussed below, since June 2008 there have been a significant number of decisions handed down not only in the district courts but also in circuit courts of appeals that serve as additional persuasive guidance. Accordingly, reconsideration of the court’s order denying the defendants’ motions for summary judgment on the § 107 claims is both authorized and justified. The court now turns to the substantive issues raised by the motions to reconsider. C. The Scope of CERCLA’s “Cost Recovery” and “Contribution” Remedies When a private party incurs costs associated with the cleanup of a hazardous waste site, CERCLA affords that party two types of claims by which it potentially may seek to recoup all or part of its costs from other parties that are entirely or partially responsible for the contamination. The first type of claim arises under § 107(a) and is commonly known as a “cost recovery” cause of action. 42 U.S.C. § 9607(a). The second type is the “contribution” cause of action arising under § 113(f). The primary argument raised by the defendants, and also by the United States as amicus curiae, in support of the motions to reconsider is that S/P are precluded from bringing claims under § 107(a) on the theory that their exclusive remedy under CERCLA is through § 113(f) contribution. The defendants take the position that S/P has incurred their expenses in question by performing cleanup activities pursuant to the PCD and the administrative agreements it encompasses, ie., the Removal Order, the NTC Removal Order, and the RI/FS Agreement. The defendants maintain that such “compelled” expenses incurred under judicial and administrative enforcement measures generally are subject to apportionment amongst the Defendants through claims by S/P for contribution under § 113(f). In those circumstances, the Defendants urge, S/P can pursue such contribution claims against them to the extent that they are not precluded by § 113(f)(2) contribution protection arising from the Foundry AOC, but that S/P cannot simply choose to characterize its claims instead as ones seeking cost recovery under § 107(a). In opposition, S/P take the position that § 107(a) does authorize cost recovery claims in circumstances that might also give rise to a § 113(f) claim, and S/P contend that the court, in its June 2008 summary judgment memorandum, was correct to interpret § 107(a) as permitting cost recovery even if the subject costs stem from cleanup activities that were “compelled” by judicial or administrative enforcement measures. Alternatively, S/P argue that, assuming § 107(a) is construed not to authorize cost recovery claims based on circumstances that also give rise to § 113(f) contribution, the circumstances underlying S/P’s claims here do not authorize contribution under § 113(f) and thus support claims under § 107(a). In a similar vein, S/P maintain that their § 107(a) claims are viable on the theory that the costs underlying their claims arose from response activities not actually “compelled” by the government’s enforcement measures. To understand fully the parties’ respective arguments and positions on these issues, it is necessary to discuss in some detail the framework of CERCLA as it relates to its cost recovery and contribution causes of action, as well as how the federal courts have interpreted those provisions. 1. The CERCLA Framework “As its name implies, CERCLA is a comprehensive statute that grants the President broad power to command government agencies and private parties to clean up hazardous waste sites.” Key Tronic Corp. v. United States, 511 U.S. 809, 814, 114 S.Ct. 1960, 128 L.Ed.2d 797 (1994). The “ ‘two ... main purposes of CERCLA’ are ‘prompt cleanup of hazardous waste sites and imposition of all cleanup costs on the responsible party.’ ” Meghrig v. KFC Western, Inc., 516 U.S. 479, 483, 116 S.Ct. 1251, 134 L.Ed.2d 121 (1996) (quoting General Electric Co. v. Litton Industrial Automation Systems, Inc., 920 F.2d 1415, 1422 (8th Cir.1990)). When faced with the need to clean up a hazardous waste site, CERCLA § 104(a) presents the federal government with the option of either cleaning up the site itself or requiring the cleanup to be financed and performed by certain enumerated entities that are subject to liability under CERCLA. 42 U.S.C. § 9604(a). Those entities, often referred to as “potentially responsible parties” or “PRPs” for short, are set forth as four categories in § 107(a)(1) through (4). They include: (1) the owner and operator of a facility where hazardous substances are located; (2) the owner or operator of a facility at the time when such hazardous substances were disposed of; (3) those who arranged for disposal, treatment, or transport of such hazardous substances by some other party; and (4) those who accepted hazardous substances for transport to disposal or treatment facilities from which there is a release or a threatened release. 42 U.S.C. § 9607(a)(l)-(4). Regardless of whether the government performs the cleanup itself or compels a PRPs to do it, the government is authorized to recover “all costs of removal or remedial action” associated with the cleanup from such PRPs, either through a civil action under § 107(a)(4)(A), or through an administrative settlement under § 122(g) or § 122(h). 42 U.S.C. §§ 9607(a)(4)(A), 9622(g) & (h). Under CERCLA’s strict liability regime, a party that falls within any of the four PRP categories of § 107(a) may be held jointly and severally liable by the government for the entire cost of a cleanup, even if the party is “innocent” in the sense that it did not contribute to the pollution at the site. See Canadyne-Georgia Corp. v. NationsBank, N.A. (South), 183 F.3d 1269, 1275 (11th Cir.1999); Atlantic Research, 551 U.S. at 136, 127 S.Ct. 2331 (“[E]ven parties not responsible for contamination may fall within the broad definitions of PRPs in § 107(a)(1)-(4)”). When the federal government determines that a cleanup is due to be performed by another party, CERCLA authorizes the use of a variety of judicial and administrative enforcement mechanisms, set forth in §§ 106 and 122. Under § 106(a), the President is authorized to direct the Attorney General to file a civil action seeking injunctive relief to abate “an imminent and substantial endangerment to the public health or welfare or the environment because of an actual or threatened release of a hazardous substance.” 42 U.S.C. § 9606(a). The President, or the EPA as his delegated agent under CERCLA, is also authorized under § 106(a) to issue unilateral administrative orders (“UAO’s”) “as may be necessary to protect public health and welfare and the environment,” that require a party to perform a cleanup. 42 U.S.C. § 9606(a). Where a party that is subject to a UAO “willfully” and “without sufficient cause” fails to comply with it, the government is authorized to bring an action in district court under § 106(b)(1) to enforce the UAO and seek additional fines and penalties. 42 U.S.C. § 9606(b)(1); see also id., § 9607(c)(3). The EPA is also generally authorized under § 122(a) to enter into settlements with other parties under which those parties are to perform cleanup activities. 42 U.S.C. § 9622(a). Under § 122(d)(1), the EPA may enter into so-called “cleanup agreements” “with respect to remedial action under [§ 106(a)].” 42 U.S.C. § 9622(d)(1). Section 122(d)(3) likewise authorizes agreements under which another party is to perform “action under [§ 104(b) ],” which references more preliminary removal actions, including investigation, monitoring, and planning tasks. 42 U.S.C. §§ 9622(d)(3) and 9604(b). Finally, CERCLA § 122(g) empowers the government to enter into “de minimis settlements” to resolve “an administrative or civil action under [§ 106] or [§ 107]” where the “settlement involves only a minor portion of the response costs at the facility concerned” and other conditions are met. 42 U.S.C. § 9622(g). From CERCLA’s enactment in 1980 until amendment by the Superfund Amendments and Reauthorization Act of 1986 (“SARA”), 100 Stat. 1613, the only express provision that potentially authorized a private party to recoup expenditures made in connection with the cleanup of a site from other private parties or polluters was § 107(a)(4)(B). Just as PRPs are liable to the government under § 107(a)(4)(A) 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,” CERCLA specified that PRPs are likewise liable under § 107(a)(4)(B) for “any other necessary costs of response incurred by any other person consistent with the national contingency plan.” 42 U.S.C. § § 9607(a)(4)(A)-(B) (footnote added). From the outset, courts agreed with virtual unanimity that § 107(a)(4)(B) authorized claims by a private party that had itself cleaned up a site against other parties responsible for the contamination. See Wickland Oil Terminals v. Asarco, Inc., 792 F.2d 887, 891 (9th Cir.1986); Walls v. Waste Resource Corp., 761 F.2d 311, 317-18 (6th Cir.1985); Artesian Water Co. v. New Castle County, 605 F.Supp. 1348, 1356 (D.Del.1985). Courts during that period also generally agreed that such a cost recovery cause of action was available even if the plaintiff was itself a PRP. See, e.g., City of Philadelphia v. Stepan Chem. Co., 544 F.Supp. 1135, 1143 (ED.Pa.1982); Jones v. Inmont Corp., 584 F.Supp. 1425, 1428 (S.D.Ohio 1984); Pinole Point Properties, Inc. v. Bethlehem Steel Corp., 596 F.Supp. 283, 291 (N.D.Cal.1984); United States v. Conservation Chem. Co., 628 F.Supp. 391, 404 (WJD.Mo.1985); but cf. D’Imperio v. United States, 575 F.Supp. 248, 253 (D.N.J.1983) (stating without citation or further analysis that “[i]n order to seek recovery under [§ 107(a)(4)(B) ] it is necessary for the plaintiff to prove that he himself is not liable for [cleanup] costs.”); Mardan Corp. v. C.G.C. Music, Ltd., 600 F.Supp. 1049, 1057 (D.Ariz.1984) (holding that a § 107(a) action was barred by, among other things, the doctrine of “unclean hands” because the plaintiff had itself contributed to contamination at the site), aff'd on other grounds, 804 F.2d 1454 (9th Cir.1986). It appears that it was at least initially assumed that private parties were not precluded from pursuing claims under § 107(a)(4)(B) by the fact that their costs had been incurred performing investigation or cleanup tasks under a CERCLA consent decree or an authorized administrative order or agreement with the EPA or a State environmental agency. Although only a few published eases prior to the 1986 SARA amendments seem to arise under those circumstances, see, e.g., Mardan Corp., 600 F.Supp. at 1054-55; Marmon Group, Inc. v. Rexnord, Inc., 1986 WL 7070 (N.D.Ill. June 16, 1986) (unpublished), no court or litigant at that time seems to have taken the position that § 107(a)(4)(B) provided no remedy where cleanup costs were compelled by prior enforcement measures. Further, amendments to the NCP regulations in late 1985 made clear that the EPA contemplated that private cleanups compelled by the agency under § 106 could support cost recovery under § 107(a). See 50 Fed.Reg. 47,929 and 47,934 (Nov. 20,1985); 40 C.F.R. § 300.680 (1986) (setting forth standards to be used by EPA in “evaluating ... proposed response actions [taken by parties other than the lead agency pursuant to section 106 of CERCLA] for the purpose of determining consistency with [the NCP] for cost recovery under section 107 of CERCLA.”). Ironically, given the nature of the issues in this action, one of the more hotly-debated issues during the first few years after CERCLA’s passage was whether government involvement in a private party’s clean up efforts was affirmatively required for an action to lie under § 107(a)(4)(B). See Frederic M. Mauhs, Judicial Limitations on the CERCLA Private Right of Action, 15 Envtl. L. 471, 483 (Spring 1985) (“The aspect of CERCLA’s private recovery provision with which courts are most uneasy is the possibility that a party might, voluntarily and without government approval or intervention, clean up any problematic waste site and then sue hundreds of transporters and generators for recovery of potentially enormous costs....”); Jeffrey M. Gaba, Recovering Hazardous Waste Cleanup Costs: The Private Cause of Action Under CERCLA, 13 Ecology L.Q. 181, 201 (1986) (“Perhaps the single most difficult issue under section 107(a)(4)(B) is the role that the government should play in approval of private cleanup plans.”). District courts initially split sharply on that question. However, the 1985 amendments to the NCP also clarified that cleanups performed without government approval could generate response costs consistent with the NCP and thus support a cost recovery action under § 107(a)(4)(B). See 50 Fed.Reg. 47,934 (revising 40 C.F.R. § 300.71) (1985). At about that same time, the issue began to reach the federal appellate courts, which, taking their cue primarily from the amended NCP, uniformly agreed that government approval or involvement was not required in an action under § 107(a)(4)(B). See Wickland Oil, 792 F.2d at 891-92; Dedham Water Co. v. Cumberland Farms Dairy, Inc., 805 F.2d 1074, 1078 n. 8 (1st Cir.1986); Tanglewood East Homeowners v. Charles-Thomas, Inc., 849 F.2d 1568, 1575 (5th Cir.1988); Richland-Lexington Airport Dist. v. Atlas Properties, Inc., 901 F.2d 1206, 1208-09 (4th Cir.1990). In addition to the foregoing cases concerning the scope of the § 107 remedy, “[a]fter CERCLA’s passage, litigation also ensued over the separate question of whether a private entity that had been sued in a cost recovery action (by the Government or by another PRP) could obtain contribution from other PRPs.” Cooper Industries, Inc. v. Aviall Services, Inc., 543 U.S. 157, 162, 125 S.Ct. 577, 160 L.Ed.2d 548 (2004). The Supreme Court further recounted: As originally enacted in 1980, CERCLA contained no provision expressly providing for a right of action for contribution. A number of District Courts nonetheless held that, although CERCLA did not mention the word “contribution,” such a right arose either impliedly from provisions of the statute, or as a matter of federal common law. See, e.g., United States v. New Castle County, 642 F.Supp. 1258, 1263-1269 (D.Del.1986) (contribution right arises under federal common law); Colorado v. ASARCO, Inc., 608 F.Supp. 1484, 1486-1493 (D.Colo.1985) (same); Wehner v. Syntex Agribusiness, Inc., 616 F.Supp. 27, 31 (E.D.Mo.1985) (contribution right is implied from § 107(e)(2)). That conclusion was debatable in light of two decisions of this Court that refused to recognize implied or common-law rights to contribution in other federal statutes. See Texas Industries, Inc. v. Radcliff Materials, Inc., 451 U.S. 630, 638-647, 101 S.Ct. 2061, 68 L.Ed.2d 500 (1981) (refusing to recognize implied or common-law right to contribution in the Sherman Act or the Clayton Act); Northwest Airlines, Inc. v. Transport Workers, 451 U.S. 77, 90-99, 101 S.Ct. 1571, 67 L.Ed.2d 750 (1981) (refusing to recognize implied or common-law right to contribution in the Equal Pay Act of 1963 or Title VII of the Civil Rights Act of 1964). Id. at 162, 125 S.Ct. 577. “Congress subsequently amended CERCLA in the Superfund Amendments and Reauthorization Act of 1986 (SARA),100 Stat. 1613, to provide an express action for contribution.” Id. Specifically, § 113(f) contains two provisions expressly setting forth circumstances in which a party “may seek contribution”: (1) “during or following any civil action under [§ 106] or under [§ 107],” § 113(f)(1); and (2) when a party 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,” § 113(f)(3)(B). 42 U.S.C. § 9613(f)(1) & (f)(3)(B). In addition to codifying the contribution cause of action, the SARA amendments included several other provisions that distinguish such claims from those for cost recovery under § 107(a). First, the nature of liability is at least generally different. Courts consistently interpret § 107(a) to provide for joint and several liability among all PRPs unless a defendant can show that a reasonable basis for apportionment of harm exists. See Burlington Northern & Santa Fe Ry. Co. v. United States, — U.S.-,-, 129 S.Ct. 1870, 1880-1881, 173 L.Ed.2d 812 (2009). By contrast, contribution calls for an apportionment of liability, with courts being authorized under § 113(f)(1) to “allocate response costs among liable parties using such equitable factors as the court determines are appropriate.” 42 U.S.C. § 9613(f)(1). Second, the statute of limitations is often longer and may be otherwise more favorable for cost recovery claims than it is for contribution claims. Under § 113(g)(3), the limitations period for an “action for contribution for any response costs or damages” claims is three years, with commencement of the period being tied to the date of a judgment or certain specified administrative orders or a judicially approved settlement. The limitations period for § 107 cost recovery claims under § 113(g)(2) is either three or six years, depending upon the type of response action performed. 42 U.S.C. § 9613(g)(2). Further, that limitations period is triggered by the performance of response work by the plaintiff, which might not occur until well after the date of a prior judgment, settlement, or order under which the plaintiff initially was compelled or agreed to perform response work at the site. Id.; see also, e.g., RSR Corp, v. Commercial Metals Co., 496 F.3d 552 (6th Cir.2007) (holding that contribution action based on costs of response action performed pursuant to 1999 consent decree was untimely filed under § 113(g)(3) where it was filed more than three years after entry of the consent decree, notwithstanding that response work was not completed until 2001). Third, and most importantly for present purposes, § 113(f)(2) provides that a party that “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.” 42 U.S.C. § 9613(f)(2). That “settlement bar does not by its terms protect against cost-recovery liability under § 107(a).” Atlantic Research, 551 U.S. at 140, 127 S.Ct. 2331. Notwithstanding the prior caselaw interpreting § 107(a)(4)(B) as authorizing actions by PRPs, after SARA’s enactment, the federal appellate courts changed course. Seeking to “direct traffic between” that section and the new § 113(f) cause of action, Atlantic Research, 551 U.S. at 132, 127 S.Ct. 2331 (quoting case below, 459 F.3d 827, 832 (8th Cir.2006)), many courts, including the Eleventh Circuit, began to hold that the § 113(f) contribution cause of action was the exclusive remedy by which a private plaintiff PRP might bring suit against others to recoup or apportion expenses associated with a cleanup, at least unless the plaintiff could not show that it was merely an “innocent” party that did not contribute to the site contamination, despite its PRP status. See Redwing Carriers, Inc. v. Saraland Apartments, 94 F.3d 1489, 1496 & n. 7 (11th Cir.1996); Rumpke of Indiana v. Cummins Engine Co., 107 F.3d 1235, 1240-41 (7th Cir.1997); see also Cooper Indust., 543 U.S. at 169, 125 S.Ct. 577 (collecting cases). “But as courts prevented PRPs from suing under § 107(a), they expanded § 113(f) to allow PRPs to seek ‘contribution’ even in the absence of a suit under § 106 or § 107(a).” Atlantic Research, 551 U.S. at 132, 127 S.Ct. 2331 (citing Aviall Servcs., Inc. v. Cooper Industries, Inc., 312 F.3d 677, 681 (5th Cir.2002) (en banc)). In its decisions in Cooper Industries and Atlantic Research, however, the Supreme Court established a different template for assessing the relationship between § 107(a) and § 113(f). Each case involved a similar factual situation in which a plaintiff, itself a PRP that had contributed to contamination at the site, had cleaned it up without having been sued under § 106 or § 107 or otherwise subject to formal government enforcement and then sued other alleged PRPs under CERCLA to recoup its cleanup costs. Cooper Industries, 543 U.S. at 163-64, 125 S.Ct. 577; Atlantic Research, 551 U.S. at 133-34, 127 S.Ct. 2331. In resolving the cases, the Supreme Court made clear that while the remedies of § 107(a) and § 113(f) “are similar at a general level in that they both allow private parties to recoup expenses from other private parties,” Cooper Industries, 543 U.S. at 163 n. 3, 125 S.Ct. 577, the latter section’s contribution cause of action does not encompass all claims that might implicate “any apportionment of expenses among PRPs.” Atlantic Research, 551 U.S. at 138, 127 S.Ct. 2331. Instead, the Court held that “§§ 107(a) and 113(f) provide two ‘clearly distinct’ remedies,” id. (quoting Cooper Indust., 543 U.S. at 163 n. 3, 125 S.Ct. 577), that “complement each other by providing causes of action ‘to persons in different procedural circumstances.’ ” Id. at 139, 127 S.Ct. 2331 (quoting Consolidated Edison Co. of N.Y. v. UGI Utilities, Inc., 423 F.3d 90, 99 (2d Cir.2005)). The Court opined that the term “contribution” in § 113(f) is used in its “traditional sense,” defined as the “ ‘tortfeasor’s right to collect from others responsible for the same tort after the tortfeasor has paid more than his or her proportionate share, the shares being determined as a percentage of fault.’ ” Atlantic Research, 551 U.S. at 138, 127 S.Ct. 2331 (quoting Black’s Law Dictionary 353 (8th ed.2004)). As such, a PRP’s right to contribution “is contingent upon an inequitable distribution of common liability among liable parties,” id. at 139,127 S.Ct. 2331, as where a “PRP ... pays money to satisfy a settlement agreement or a court judgment” to reimburse another party for costs that it incurred in performing or overseeing a cleanup. Id. at 139 & n. 6, 127 S.Ct. 2331. But such contingency is not satisfied, the Court held, where a plaintiff seeks to recover or apportion costs of a cleanup it performed voluntarily, without ever having been sued under § 106 or § 107, settling its liability, or in response to an administrative order. See Cooper Industries, 543 U.S. at 165-68 & n. 5, 125 S.Ct. 577; see also Atlantic Research, 551 U.S. at 139 n. 6,127 S.Ct. 2331. By contrast, Atlantic Research held that a plaintiff that itself has performed a cleanup under those same voluntary conditions is authorized to bring a claim to recoup its response costs under § 107(a)(4)(B), essentially validating earlier federal appellate cases like Wickland Oil that had sanctioned cost recovery claims arising from private cleanups undertaken