concurring in part and dissenting in part.
I join the court in holding that the final rule on the Standards of Performance for New Stationary Sources and Emissions Guidelines for Existing Source: Commercial and Industrial Solid Waste Incineration Units (“Definitions Rule”), is contrary to the plain text of the Clean Air Act. I also agree that, as a result, the related rule, the National Emission Standards for Hazardous Air Pollutants for Industrial, Commercial, and Institutional Boilers and Process Heaters (“Boilers Rule”), must be substantially revised. Where I differ is on the appropriate remedy.
The reality in this case is that the question of whether to vacate or remand the rules has been fully addressed by the parties. The initial discussion in the parties’ briefs was supplemented by a series of motions and responses by the parties. Thus, the adversarial process has been observed. The question, then, is whether the parties have persuaded the court of the appropriate remedy. The court has no reason to postpone a decision on the question in this case. The fact that over the years the court’s remedies in different cases fail to reveal a consistent pattern, see concurring opinion of Randolph, J., does not pose an obstacle to proceeding now nor necessarily mean that the remedial responses in particular cases were inappropriate. The particular fact-intensive circumstances in the cases that come before the court involving a variety of regulatory *429schemes may well mean that there will be no one-rule-fits-all solution.
Where the court has concluded that a final rule is deficient, the court has traditionally not vacated the rule if doing so would have serious adverse implications for public health and the environment. See, e.g., Sierra Club v. EPA, 167 F.3d 658, 664 (D.C.Cir.1999); Nat’l Lime Ass’n v. EPA, 233 F.3d 625, 635 (D.C.Cir.2000). There have been exceptions, but the court has usually offered a reasoned explanation for its decision, as in Cement Kiln Recycling Coal. v. EPA, 255 F.3d 855, 872 (D.C.Cir.2001), which distinguished Sierra Club and National Lime because the public health considerations favoring remand were offset by rule challenges by industry that the court did not reach but appeared meritorious. Here, the court has rejected industry contentions as regards the Definitions Rule and the interests of the Municipal Petitioners, which only challenged the Boilers Rule, are protected by a separate remand and stay of the compliance date in the Boilers Rule. Order of Mar. 12, 2007. The court is not reaching the merits of any parties’ challenge to the Boilers Rule because of the interrelationship between the two rules and the need to afford EPA an opportunity to overhaul that rule in view of the court’s conclusion about the Definitions Rule. See Op. at 1262. But the court can hardly suggest Industry contentions regarding the Boilers Rule appear meritorious. See, e.g., Sierra Club v. EPA, 479 F.3d 875, 883 (D.C.Cir.2007); Nat’l Lime, 233 F.3d at 633-34.
The second reality in this case stems from the nature of the court’s decision. It is evident from the court’s recognition that EPA must conduct a “wholesale revision on remand,” Op. at 1262, that a considerable period of time may pass before EPA promulgates the revised rules. Although EPA has suggested that a stay of the mandate of the court would be appropriate, see Reply in Support of Motion for Voluntary Partial Vacatur and Remand at 3-4, as a practical matter, a lengthy or indefinite stay of the mandate is problematic. Federal Rule of Appellate Procedure 41 calls for the mandate to issue in seven days; our Circuit rule contemplates that a stay of the mandate will ordinarily be for no more than 90 days, D.C. CIR. R.41(a)(2); and our stays of the mandate have tended, in fact, to be for months, see, e.g., Chamber of Commerce v. SEC, 443 F.3d 890, 909 (D.C.Cir.2006); U.S. Telecom Ass’n v. FCC, No. 00-1012, 2002 WL 31039663, at *1, 2002 U.S.App. LEXIS 18823, at *1 (D.C.Cir. Sept. 4, 2002), not years. We know that the agency response may not even be a matter of a few years; for example, it took EPA ten years to respond in Engine Mfrs. Ass’n v. EPA, 20 F.3d 1177 (D.C.Cir.1994), and fifteen years to respond to a remand of the rule in Envtl. Def. Fund v. EPA, 898 F.2d 183 (D.C.Cir.1990); 70 Fed.Reg. 59,582 (Oct. 12, 2005), and then it did so only after a petition for a writ of mandamus had been filed. Even assuming these cases are outliers, EPA has not suggested its response here will be a matter of months. Nor has EPA suggested it could promptly adopt an interim rule were the court to vacate the current rules.
Moreover, it may not always be clear what motivates an agency to act promptly or not after the court has identified problems with its initial rulemaking. There may be professional or political incentives, or other matters to which the agency has accorded a higher priority. Staffing and available resources might affect the timing of the agency’s response. So might a technological or scientific breakthrough, or lack thereof. Also, the agency may change its mind or abandon its initial rule or Congress may change the law. Or the court’s decision may not impact the agency’s pursuit of its regulatory goals. Any *430mix of these factors or others could affect the expected response time to the court’s ruling. Consequently, neither vacating nor remanding, with or without a court imposed deadline, assures a prompt agency response. Vacating a rule removes it from the agency’s docket, but interested parties may still seek to encourage or delay further agency action. Remanding leaves the agency’s initial approach in effect, and may suggest there is no urgency to act, yet interested parties may take a different view. Even if an agency does not welcome mandamus-driven agency action, the possibility of mandamus may serve as an incentive not to delay unduly regardless of whether the court vacates or remands. Even so, a court-imposed deadline for agency action may not easily be enforced.
EPA has defined the serious adverse implications for public health and the environment resulting from the pollution emitted by the sources regulated by the two challenged rules. All of the hazardous air pollutants emitted by boilers and incinerators cause serious adverse health effects. 69 Fed.Reg. 55,218, 55,220-22 (Sept. 13, 2004). EPA has stated “[h]uman exposure to these combustion air toxics occurs both directly and indirectly and leads to cancer, respiratory diseases, and possibly developmental abnormalities. A preliminary screening analysis suggests that ecosystems are also at risk from these air pollutants.” 64 Fed.Reg. 52,828, 53,014 (Sept. 30, 1999). Given the delay likely attendant to the promulgation of new rules or the re-promulgation of partially unlawful rules affecting public health and the environment, Environmental Petitioners favor a remand because although the standards in the two challenged rules may be inadequate, they provide some protection from the hazardous air pollutants emitted by the regulated sources. See Opp’n of Envtl. Pet’rs to EPA’s Mot. for Partial Vacatur and Cross-Mot. for Deadline to Govern Remand at 2; Resp. & Opp’n of Indus. Intervenors to Envtl. Pet’rs’ Opp’n to EPA’s Mot. for Voluntary Partial Vacatur and Cross-Mot. for Deadline to Govern Remand at 9-10.
A third reality in this case involves the status of industry compliance. Environmental Petitioners advise, and neither EPA nor industry intervenors disputes, that the compliance date for sources under the Boilers Rule is four months away, and new boilers and process heaters have been in compliance since 2004. Id. at 3. Indeed, as regards the Boilers Rule, although not as regards pollutants from incinerators subject to the Definitions Rule, EPA suggests that many sources will remain subject to the current MACT regulations under the Title V permits. See Reply in Support of Mot. for Voluntary Partial Vacatur and Remand at 5; Resp. & Opp’n of Indus. Intervenors to Envtl. Pet’rs’ Opp’n to EPA’s Mot. for Voluntary Partial Vacatur and Cross-Mot. for Deadline to Govern Remand at 9-10.
Under the circumstances, a remand instead of vacatur seems “the better course,” Cement Kiln, 255 F.3d at 872, because the rules would ensure greater protection to public health and the environment during the time EPA will need to develop and promulgate new rules. See Reply in Support of Motion for Voluntary Partial Vacatur and Remand at 8-10. No party has indicated that it wishes to apply for certiorari review by the Supreme Court. See concurring opinion of Judge Randolph.
Nonetheless, without questioning the reality of the harms to public health and the environment that EPA has identified and the status of industry compliance, the court concludes no protection is better than some protection to the public health and the environment in the interim. The court’s reliance on Friends of the Earth, Inc. v. EPA, 446 F.3d 140 (D.C.Cir.2006), see Op. at 1261, hardly supports an unqualified vacatur of the rules. Although that *431case concerned the effect of pollution on aquatic and plant life as distinct from human life, the court remanded the case to the district court to determine “the shortest reasonable timetable” for “an expedited schedule for further rulemaking,” Friends, 446 F.3d at 148. Moreover, while the case was not moot, the necessary local action had already addressed the environmental problem. Id. at 147. The distinctions that the court draws with our other remands are makeweight arguments; for example, in National Lime, 233 F.3d at 635, EPA also had failed to follow the statute in promulgating a rule and the court remanded; EPA could not, as the court implies, Op. at 1261, promulgate a rule on remand that continued to violate the statute. Rather, agency shortcomings in rulemakings have been the gist of remands. Cf. Envtl. Def. Fund, 898 F.2d at 190. The other opinion on which the court relies, Alabama Power Co. v. EPA, 40 F.3d 450, 456 (D.C.Cir.1994), provides no analysis in support of vacatur. Whatever may or may not be the merits of procedural uniformity, see concurring opinion of Judge Randolph, the posture of this case allows the court to decide the remedy now. The supplementary filings have provided the court with the information it needs,1 and it would be a waste of judicial and party resources to require new filings on remedy in support of a stay upon vacation of the rules.
For these reasons, I would remand the two challenged rules to EPA rather than vacate them.
. Industry-intervenors's concern, referenced in the concurring opinion of Judge Randolph, arose in the context of opposing Environmental Petitioner’s request for a remand with a two year deadline for EPA to respond on the basis that EPA could not know the magnitude of the work it must undertake on remand until this court’s opinion issues. See Resp. & Opp’n of Indus. Intervenors to Envtl. Pet’rs' Opp’n to EPA's Mot. for Voluntary Partial Vacatur and Cross-Mot. for Deadline to Govern Remand at 4; id. at 5, 10.