Circuit Judge, dissenting:
Judge Wilkey’s careful explanation of the genesis of this litigation need not be repeated.1 In a nutshell, Congress, in passing the Clean Air Act Amendments of 1977,2 placed EPA in a dilemma by giving facially contradictory instructions in Sections *78165(a)3 and 1684 regarding the effective date of Section 165(a)’s stringent preconstruction review and permitting requirements. Its counsel styles EPA’s response to this predicament as an “interpretation” 5 of the Amendments but, as the court rightly recognizes,6 in truth EPA deemed the search for a consistent congressional directive futile and proceeded to legislate.7 It charted a “prudent”8 middle course between Sections 165(a) and 168, which the court today sustains.
I respectfully disagree. Perhaps surprisingly when an extremely complicated statute must be construed and any resulting interpretation entails tremendous economic and environmental consequences, the source of my dissension can be simply stated. Congress may have meant Section 165(a) to become effective immediately upon enactment of the 1977 Amendments. It may, on the other hand, have intended Section 165(a)’s requirements to govern only after their incorporation into state implementation plans pursuant to the procedure established by the Clean Air Act, with preexisting federal regulatory specifications already written into existing state plans to control in the interim. But plainly enough for me, Congress contemplated that one point or the other would become the effective date, and did not delegate responsibility for specifying an entirely different date to EPA. When Congress in a statute indisputably says “A” or “B” but does not make clear which, interpretation must, in my view, be utterly impracticable before the agency responsible for administering the law can say “C.”
The court throws up its hands at the formidable construction problem presented by Sections 165(a) and 168. To be sure, the issue cannot be resolved by giving every provision of the 1977 Amendments its most natural and expansive meaning when considered in isolation. But scrutinized in light of the entire statute and its legislative history, I think Sections 165(a) and 168 can be reconciled,9 and thus I side with Lord Wensleydale:
It is a very useful rule in the construction of a statute, to adhere to the ordinary meaning of the words used, and to the grammatical construction, unless that is at variance with the intentions of the legislature to be collected from the statute itself, or leads to any manifest absurdity or repugnance, in which case the language may be varied or modified, so as to avoid such inconvenience, but no further.10
I. THE STATUTE
It is axiomatic in a democracy that courts are to construe statutes so as to effectuate the lawgivers’ intent.11 Yet the vicissitudes *79and occasionally the impossibility of ascertaining a uniform legislative purpose,12 and the importance of reading statutes the way affected parties naturally would,13 has led to the rule that the intention of the legislature must be primarily determined from the language of the entire statute itself.14 So I now turn to review the critical provisions of the Clean Air Act Amendments of 1977.
A. Section 168
Section 168 is strictly an interim measure, as its caption attests.15 It provides in full:
PERIOD BEFORE PLAN APPROVAL
Sec. 168. (a) Until such time as an applicable implementation plan is in effect for any area, which plan meets the requirements of this part to prevent significant deterioration of air quality with respect to any air pollutant, applicable regulations under this Act prior to enactment of this part shall remain in effect to prevent significant deterioration of air quality in any such area for any such pollutant except as otherwise provided in subsection (b).
(b) If any regulation in effect prior to enactment of this part to prevent significant deterioration of air quality would be inconsistent with the requirements of section 162(a), section 163(b) or section 164(a), then such regulations shall be deemed amended so as to conform with such requirements. In the case of a facility on which construction was commenced (in accordance with the definition of ‘commenced’ in section 169(2)) after June 1, 1975, and prior to the enactment of the Clean Air Act Amendments of 1977, the review and permitting of such facility shall be in accordance with the regulations for the prevention of significant deterioration in effect prior to the enactment of the Clean Air Act Amendments of 1977.16
Subsection (a) incontrovertibly requires that the preexisting federal regulations designed to prevent significant deterioration shall17 remain in effect until the new im*80plementation plans are proposed by the states and approved by EPA. Subsection (bf unequivocally specifies the only exceptions to this principle.18
The Environmental Groups’ effort to dismiss Section 168 as a mere “savings clause” deserves the short shrift the court gives it.19 That function is adequately served by Section 406(b).20 Further, during the period of its operation, Section 168(a) does not merely authorize, it requires, EPA’s prior PSD regulations to continue in effect, save as amended in Section 168(b).
The Environmental Groups develop two other arguments to circumvent the difficulties Section 168 poses for their position. In the first place, they maintain that EPA possessed authority to implement Section 165 immediately and independently of state plans.21 This, of course, does not avoid conflict with Section 168(a), which governs until “an applicable implementation plan is in effect,”22 and in any event is wholly alien to the Clean Air Act’s framework, which basically requires federally-established standards to be applied to individual sources of pollution through state implementation plans. The Supreme Court has explained this division of functions:
The Agency is plainly charged by the Act with the responsibility for setting the national ambient air standards. Just as plainly, however, it is relegated by the Act to a secondary role in the process of determining and enforcing the specific, souree-by-source emission limitations which are necessary if the national standards it has set are to be met. Under § 110(a)(2), the Agency is required to approve a state plan which provides for the timely attainment and subsequent maintenance of ambient air standards, and which also satisfies that section’s other general requirements. The Act gives the Agency no authority to question the wisdom of a State’s choices of emission limitations if they are part of a plan which satisfies the standards of § 110(a)(2), and the Agency may devise and promulgate a specific plan of its own only if a State fails to submit an implementation plan which satisfies those standards. § 110(c). Thus, so long as the ultimate effect of a State’s choice of emission limitations is compliance with the national standards for ambient air, the State is at liberty to adopt whatever mix of emission limitations it deems best suited to its particular situation.23
Congress adhered to this allocation of authority in devising the 1977 PSD Amendments. Congress added to Section 110(a)(2)24 of the Act the requirement that each state plan include a program for enforcing the PSD standards.25 Section 161 is of the same tenor.26
Secondly, the Environmental Groups contend that EPA had authority to implement Section 165 immediately by directly amending applicable state implementation plans.27 In support of this view they cite Section *81110(c).28 Unlike the majority,291 would reject this argument without equivocation. Section 110(c) clearly contemplates that a state be given the initial opportunity to submit a plan that complies with federal standards.30 Only if the state fails to submit timely a satisfactory plan may EPA act.31 No state was then in default of its obligations under the 1977 Amendments since Section 406(d)(2)32 gave the states until nine months after EPA fashioned necessary regulations to revise their plans in accordance with the Amendments. These regulations were promulgated on June 19, 1978,33 and thus EPA’s action under review here cannot be justified by reliance on Section 110(c).
Nor should Section 167 34 be read to authorize immediate implementation of Section 165 through federal revision of state plans. In the first place, as the court notes,35 Section 167 grants EPA the power to take action against major emitting facilities that fail to conform to the requirements of the Act, and that, of course, leads back to the original dispute over whether Section 165 or Section 168 sets out the Act’s requirements during the interim period. In the second place, even were Section 167 otherwise an appropriate' warrant for immediate implementation of Section 165, conflict with Section 168 would not be avoided. Section 168(a) requires that existing PSD regulations continue until “an applicable implementation plan”36 is in effect, and Section 110(d) defines “applicable implementation plan” as “the implementation plan, or most recent revision thereof, which has been approved under [Section 110(a)] or promulgated under [Section 110(c)] and which implements the requirements of this section.”37 Thus, action pursuant to Section 167 would not constitute promulgation of an “applicable implementation plan.”
The Environmental Groups do not focus on the one part of Section 168 oh which a marginally plausible argument in support of their position can be built — the last sentence of subsection (b).38 Congress there specified that a facility on which construction was “commenced” — defined to mean a facility whose owner or operator has obtained all necessary permits and who has either begun building or has entered into agreements, which cannot be modified without substantial loss to the owner, to undertake *82and complete construction shortly39 — after June 1, 1975, but before enactment of the 1977 Amendments shall be subject to the preexisting PSD regulations. It could be argued that the negative implication can properly be drawn: that facilities on which construction had not been commenced before enactment of the 1977 Act are subject to the new, more stringent preconstruction review and permitting standards set out in Section 165. The second sentence of subsection (b) would thus be an exception to the rule of subsection (a) and the puzzle of accommodating Section 168 with Section 165(a) would be solved. This reconciliation is unsatisfactory, however. Negative implications, of course, are not valid as a matter of deductive logic and are usually considered weak indicators of congressional intent.40 More importantly, to construe the last sentence of subsection (b) as vaguely implying that which would have been expressly commanded by inclusion of Section 165(a) in the enumeration of the immediately preceding sentence is to impute to Congress a Kafkaesque obscurantism.41 Further, the origin of the curious second sentence of Section 168(b), which will be explicated below, reveals that a much more limited role was envisioned for that provision.42
To sum up, until new state implementation plans go into effect, Section 168, on its face at least, requires, not merely permits, preexisting federal regulations for the prevention of significant deterioration in the air quality of attainment areas of the country to remain in effect except as they are specifically amended by the provisions of the 1977 Amendments listed in Section 168(b), and Section 165(a) is not one of those provisions.
B. Section 165
The linchpin of the Environmental Groups’ position is the introductory clause of Section 165(a).43 It provides that “[n]o major emitting facility on which construction is commenced after the date of the enactment of this part, may be constructed in any area to which this part applies unless —. . ,”44 the requirements spelled out in the remainder of Section 165(a) are met. Read in light of the definition of “commenced” set out in Section 169(2)(A),45 this portion of Section 165(a) seems clear enough at first blush: contrary to Section 168, existing PSD regulations should not remain in force pending adoption of implementation plans in conformance with the 1977 Amendments.
Upon closer examination, however, even the introductory language of Section 165(a) is not completely free from ambiguity. Preconstruction review and permitting of major emitting facilities is expressly required only in areas “in which this part *83applies.'’46 “[T]his part” means Part C of Title I of the Clean Air Act.47 The statute does not specify the areas in which Part C applies — the attainment areas. It does, however, establish a procedure for determining the “clean air” regions of the Nation.
Section 161 requires state implementation plans to include such measures “as may be necessary ... to prevent significant deterioration of air quality in each region (or portion thereof) identified pursuant to section 107(d)(1)(D) or (E).”48 Section 107(d)(1)49 commands each state to submit to EPA within 120 days of enactment of the 1977 Amendments a list of those portions of the state that do not meet a national ambient air quality standard, and a list of both those that meet all such standards and those which, for lack of sufficient information, cannot be classified and therefore are deemed clean air areas. Section 107(d)(2)50 directs EPA within the next 60 days to review these submissions and to promulgate them with such modifications as considered necessary. EPA published its list of clean air areas on March 3, 1978,51 almost seven months after enactment of the 1977 Act. Thus, the introductory clause of Section 165(a) itself suggests that review and permitting pursuant to that section’s standards could not have been carried out immediately upon enactment.
The Environmental Groups and the court respond to this interpretation of Section 165(a) by asserting that the phrase in question “was intended solely to define the geographic scope of the section’s application and not to postpone its effective date.”52 For one thing, the court says, “§ 163(b) of the Act, like § 165, applies by its terms to designated ‘clean air’ areas, and yet Congress directed specifically in § 168(b) that § 163(b) was to take effect on 7 August 1977.”53 This example, it seems to me, is not dispositive. The increments and ceilings established by Section 163(b)54 apply in “any” class I, II or III area55 — regions ultimately to be designated pursuant to the procedures of Section 107(d).56 However, Section 168(b) amended existing regulations only to the extent that they were “inconsistent with the requirements” 57 of Section 163(b). EPA’s preexisting PSD regulations designated Class I, II and III58 areas and those designations are consistent with Section 163(b) until the job of redesignation pursuant to Section 107(d) is completed. In other words, the new increments of Section 163(b) replaced EPA’s standards but EPA’s designation .of clean air areas remains in force until modified pursuant to Section 107(d). Section 165, on the other hand, is not mentioned in Section 168(b), so the requirements of Section 165 simply replace the old preconstruction review and permitting regulations, which were applicable in all areas of the country.59
As a further ground for rejecting the idea that the designation of attainment areas must precede application of Section 165(a), the court points again to “the immediately preceding phrase, which provides that no nonconforming facility may be con*84structed after 7 August 1977,”60 and expresses reluctance to find inconsistency within a single subsection.61 I see no necessary inconsistency. Even if the clause-proscribing construction of nonconforming plants after August 7, 1977 was intended to be read in the natural way adopted by the court, there is no unavoidable conflict with the view that Congress contemplated that designation of clean air areas would precede the review specified in Section 165(a). Rather, the upshot of the court’s construction might just as well be that Congress intended a moratorium on construction of major emitting facilities until such time as attainment areas had been designated.
Other provisions of Section 165 buttress the conclusion that the preconstruction review and permitting process spelled out in that section could not have been implemented on August 7, 1977. Section 165(e)(1) is perhaps the clearest on this score:
The review provided for in subsection (a) of this section shall be preceded by an analysis in accordance with regulations of the Administrator, promulgated under this subsection, which may be conducted by the State (or any general purpose unit of local government) or by the major emitting facility applying for such permit, of the ambient air quality at the proposed site and in areas which may be affected by emissions from such facility for each pollutant subject to regulation under this chapter which will be emitted from such facility.62
Section 165(e)(1) unmistakably requires air quality analyses, conducted pursuant to federal regulations, to precede permitting under Section 165(a), and both promulgation of the regulations and production of the analyses take time.63 The court perceives “no reason why the effective date in § 165(e) should control the effective date provided in § 165(a).”64 That position, in my view, is defensible only if, again, the proscription of Section 165(a) was intended to flatly ban new construction until the Act’s new mechanisms are geared up.
In sum, although Section 165(a)’s apparent prohibition of construction of major emitting facilities whose owners or operators failed to make the demonstration called for in that section could have been invoked on August 7, 1977, the showing required for approval could not conceivably have been made until considerably later. This naturally leads to two questions: Did Congress think that the national interest in preservation of our clean air areas warranted imposition of a moratorium on construction of major emitting facilities until the more stringent requirements of the 1977 Amendments could be met? If not, and if Congress intended the prior preconstruction review and permitting regulations to apply to facilities on which construction was “commenced” 65 prior to implementation of the procedures and standards specified in the 1977 Act, what explains the phrase in Section 165(a) that seemingly provides that no facility that does not meet the new requirements may be constructed after August 7, 1977? To explore these issues, I next delve into the legislative history of Sections 165 and 168.
II. THE LEGISLATIVE HISTORY
As the court underscores,66 Section 165 was basically derived from a Senate bill, S. 252,67 while Section 168 evolved from a House bill, H.R. 6161.68 An understanding *85of what those bills originally provided, and how they were modified in conference, is crucial to excavation of Congress’ purpose.
A. The Senate Bill
Section 5(a) of S. 252 would have required the states to submit revised implementation plans incorporating the new PSD standards within seven months after enactment.69 Several provisions must be consulted to divine the Senate’s approach to the period before submission of the state plans.
Section 6 of S. 252, the predecessor of Section 165(a), would have added a new subsection (g)(4) to Section 110 of the Clean Air Act.70 The introductory clause of proposed Section 110(g)(4) specified that “[n]o major emitting facility on which construction is commenced after June 1, 1975, may be constructed in any area designated under this subsection — . . ,”71 unless certain requirements were met. Congress did not conjure the June 1, 1975, date out of thin air. On the contrary, in passing Part C of Title I of the Clean Air Act, Congress was essentially codifying, revising and strengthening EPA’s PSD regulations 72 promulgated in 1974 and 1975 pursuant to court order.73 These regulations provided for preconstruction review only of projects which had “not commenced construction or modification prior to June 1, 1975.”74 “Commenced” was defined to mean “that an owner or operator has undertaken a continuous program of construction or modification or that an owner or operator has entered into a contractual obligation to undertake and complete, within a reasonable time, a continuous program of construction or modification.” 75
The Senate was disturbed by the looseness of EPA’s definition of “commenced.” The Senate Report expressed the belief that “it is appropriate to require review of facilities which have not actually begun construction or so changed their position as to risk substantial loss if the project is canceled or modified.”76 Accordingly, Section 677 of the Senate bill adopted substantially the definition of “commenced” ultimately enacted in Section 169(2)(A)78 The Senate bill thus narrowed EPA’s definition of “commenced” so as to capture within the statute proposed facilities for which permits had been obtained and contracts let, provided the owner’s obligations could be altered without substantial loss. It did not, however, seek to apply the Act’s standards to facilities “commenced” — as defined in the new, stricter way — prior to enactment of the 1977 amendments. Following its new definition of “commenced,” S. 252 stated:
Provided, That in the case of a facility on which construction was commenced in ac*86cordance with this definition after June 1, 1975, and prior to the enactment of the Clean Air Amendments of 1977, the review and permitting of such facility shall be in accordance with the regulations for the prevention of significant deterioration in effect prior to the enactment of the Clean Air Amendments of 1977.79
Neither the introductory clause of proposed Section 110(g)(4) nor the definition of “commenced” was designed to establish which standard of preconstruction review governed sources on which construction is commenced after enactment but before submission and approval of revised state implementation plans. That task was assigned to proposed Section 110(g)(7)(A), which read:
Until a revision of the implementation plan in accordance with this subsection is submitted and approved, significant deterioration for those pollutants covered by such regulations shall be regulated pursuant to applicable regulations and procedures for prevention of significant deterioration established under authority of the Clean Air Act in effect prior to the enactment of the Clean Air Amendments of 1977, except as those regulations provide for designations of nondeterioration areas which allow increases in emissions of air pollutants or any reduction in air quality inconsistent with paragraph (1) and (2) of this subsection, or do not require the degree of control required by paragraph (6)(A) of this subsection, or are otherwise inconsistent with the requirements of this subsection.80
This provision’s stated exceptions largely swallowed its rule. Preexisting regulations were continued in order to avoid any regulatory hiatus, but those regulations inconsistent with the new statutory PSD requirements were superseded.
In summary, the Senate bill did through proposed Section 110(g)(7)(A) what the Environmental Groups suggest was done by the introductory clause of Section 165(a), but the Senate did not assign that role to the latter. The introductory clause of what was to become Section 165(a), in conjunction with the definition of “commenced” and its proviso, was concerned with extension of preconstruction review and permitting requirements to owners and operators who could comply with the PSD81 standards before beginning construction without incurring substantial economic loss or liability by breaching construction contracts.
B. The House Bill
The House bill, H.R. 6161,82 afforded the states a longer time to submit revised implementation plans than did the Senate bill. Section 119 of H.R. 6161 gave the states a minimum of one year to develop their plans.83 Section 108(a) of H.R. 6161 specified the rule of law to apply during the interim.84 It would have added Section 160(h) to the Clean Air Act, to read as follows:
(1) Until such time as an applicable implementation plan is in effect for any area which plan meets the requirements of this section to prevent significant deterioration of air quality with respect to *87any air pollutant, applicable regulations under this Act in effect prior to enactment of this section shall remain in effect to prevent significant deterioration of air quality in any such area for any such pollutant, except as otherwise provided in paragraph (2) of this subsection.
(2) If any regulation in effect prior to enactment of this section to prevent significant deterioration of air quality would be inconsistent with the requirements of subsection (c)(2) and (c)(3)(B), then such regulations shall be deemed amended so as to conform with such requirements.85
The House Report contained a section captioned “Safeguards against moratorium on growth.”86 In one passage in this section, the Committee explained the rationale of proposed Section 160(h):
Sixth, the committee has included additional safeguards in the section regarding economic development. These include:
(5) No temporary lapse of ongoing programs during the time necessary to propose and promulgate new regulations under the section; existing regulations (as amended by this section) will remain in effect until such new regulations are in effect.87
Simply put, enactment of the House bill would have explicitly resolved the controversy at bar in favor of the Industry Groups’ position: There would be no moratorium on permitting of new facilities; pending submission of new state implementation plans, existing regulations would govern.
C. Conference Decisions
The pertinent decisions of the Conference Committee can be simply sketched. Determining their significance, however, is fraught with some uncertainty.
First, and perhaps foremost, the Committee agreed to adopt substantially the transitional approach embodied in proposed Section 160(h) of the House bill.88 Section 168 of the enacted legislation 89 differs in just two ways from proposed Section 160(h). For one thing, the two provisions deemed immediately effective in Section 160(h) were recast as three such provisions in Section 168(b), but this was a change in nomenclature, not substance.90 For another, the proviso to the definition of “commenced” found in the Senate bill91 was framed in sentence form and tacked behind the specified exceptions to the rule that preexisting PSD regulations are to govern pending submission and approval of revised implementation plans.92 It will be recalled that the proviso’s sole function was to avoid unfair retroactive application of the new preconstruction review and permitting standards.93 Consequently, although the Conference Committee’s inclusion of that provision in Section 168(b) still seems curious, the negative-implication argument discussed above94 is unpersuasive.
Second, the Committee adopted the substance of proposed Section 110(g)(4)95 of *88the Senate bill and recast it as Section 165(a).96 It also adopted the Senate’s definition of “commenced.” 97 The Senate version was not appropriated without relevant modification, however. The Senate bill, it will be remembered, narrowed the definition of “commenced” found in EPA’s regulations, and accordingly expanded the reach of the preconstruction review and permitting requirements.98 Proposed Section 110(g)(4) of S. 252 imposed the new standards on all major emitting facilities on which construction had not started by June 1, 1975,99 and then in a proviso stipulated that facilities on which construction began after June 1, 1975, but before enactment of the 1977 amendments would be governed by the preexisting regulations.100 The Conference Committee changed the June 1, 1975, date to the date of enactment of the Act,101 thus allowing those facilities under construction on June 1,1975 — by EPA’s definition of “commenced,” even though not under the new definition — to remain exempt from all preconstruction review and permitting strictures.
Third, the Conference Committee failed to adopt the Senate’s proposed Section 110(g)(7)(A),102 the transitional provisional mandating application of the new preconstruction review standards to facilities on which construction is commenced after enactment but before applicable revised implementation plans are in force.
Without suggesting that these actions evidence unmistakably a consistent congressional intent, I do think the Conference Committee’s decisions can fairly be taken to reflect approbation of the House approach to preconstruction review during the period state implementation plans are being developed. In the first place, the House’s specific response to this issue was adopted.103 The House Report had emphasized the importance of this provision in avoiding severe economic disruption,104 and it seems difficult to believe that although the provision was ratified its rationale was not. Secondly, the Senate’s explicit interim measure was rejected.105 Lastly, the introductory clause of Section 165(a) was primarily concerned with setting the effective date for application of the statute’s new definition of “commenced,” not with setting the date for application of the new PSD standards or with imposing a moratorium on new construction.106 In sum, the Conference Committee, it seems to me, opted for an orderly transition to the new preconstruction review and permitting standards with a minimum of economic dislocation. It decided to continue the existing PSD regulations in effect until the states could submit and garner endorsement of revised implementation plans.107
*89III. CONCLUSION
This is by no means the first time a court has been summoned to construe arguably inconsistent provisions of a single law. The court’s acceptance of the superficial conflict here and its administrative solution may be unprecedented, however. The traditional judicial response to such a situation is aptly illustrated by the Supreme Court’s decision in Clark v. Uebersee Finanz-Korp.108 In that case, the Court was called upon to construe Sections 5(b) and 9(a) of the Trading with the Enemy Act,109 as amended by the First War Powers Act of 1941.110 Section 5(b) granted the President the power to seize “any property or interest [subject to the jurisdiction of the United States] of any foreign country or national thereof.”111 Section 9(a), on the other hand, permitted “any person not an enemy or ally of enemy” 112 to sue for reclamation of appropriated property. Despite the broad language of Section 5(b), the Court declined to hold that a non-enemy foreign national whose seized property was never owned or controlled by an enemy had no remedy under Section 9(a).113 The Court explained its approach in language from which I take my cue today: “We are dealing with hasty legislation which Congress did not stop to perfect as an integrated whole. Our task is to give all of it . . . the most harmonious, comprehensive meaning possible.”114
Undoubtedly, Congress could enact flatly inconsistent provisions, each of which would simply cancel the other out. And it is conceivable that Congress could simply say in one breath that a particular statutory provision is immediately effective and in the next say that its effectiveness is subject to conditions precedent, the fulfillment of which requires time. Were this all that Congress did in enacting the Clean Air Act Amendments of 1977, I might join in the court’s opinion. But, in my view, the Act’s structure and history enable a reconciliation of the apparent conflict between Sections 165(a) and 168.115 I would hold that EPA’s preexisting PSD regulations, as amended by Section 168(b), govern the preconstruction review and permitting of pollution sources on which construction is commenced after August 7, 1977, but before revision and approval of applicable state implementation plans, and consequently would reach no other issue in the case. Accordingly, I respectfully dissent.
. See Majority Opinion (Maj. Op.), 195 U.S.App.D.C., at 36-46, 600 F.2d at 850-860.
. Pub.L. No. 95-95, 91 Stat. 685 (Aug. 7, 1977), amending the Clean Air Act, 42 U.S.C.A. §§ 7401-7626 (1978).
. 42 U.S.C.A. § 7475(a) (1978), quoted in part in text accompanying note 44 infra.
. 42 U.S.C.A. § 7478 (1978), quoted in full in text accompanying note 16 infra.
. Brief for EPA 52.
. Maj. Op., 195 U.S.App.D.C., at 59-60, 63-65, 600 F.2d at 873-874, 877-879.
. See 42 Fed.Reg. 57479 (Nov. 3, 1977) (proposed rules); 43 Fed.Reg. 26380 (June 19, 1978) (final rules).
. “In light of the drafting inconsistencies between Sections 165(a) and 168, EPA feels that the most prudent course is to implement Section 165(a) as quickly as possible, but through the rulemaking process.” 42 Fed.Reg. 57479 (Nov. 3, 1977).
. See Parts I, II infra.
. Becke v. Smith, 2 M & W 191, 195 (1836). See, e.g., Weinberger v. Hynson, Westcott & Dunning, Inc., 412 U.S. 609, 631-632, 93 S.Ct. 2469, 2484, 37 L.Ed.2d 207, 224 (1973); Montgomery Charter Serv., Inc. v. Washington Metropolitan Area Transit Comm’n, 117 U.S.App.D.C. 34, 38, 325 F.2d 230, 234 (1963); Maiatico v. United States, 112 U.S.App.D.C. 295, 301, 302 F.2d 880, 886 (1962); Bailey v. United States, 511 F.2d 540, 546, 206 Ct.Cl. 169 (1975).
. See, e.g., Philbrook v. Glodgett, 421 U.S. 707, 713, 95 S.Ct. 1893, 1898, 44 L.Ed.2d 525, 533 (1976); National R. R. Passenger Corp. v. National Ass’n of R. R. Passengers, 414 U.S. 453, 458, 94 S.Ct. 690, 693, 38 L.Ed.2d 646, 652 (1974); City of New York v. Train, 161 U.S. App.D.C. 114, 123, 494 F.2d 1033, 1042 (1974), aff'd, 420 U.S. 35, 95 S.Ct. 839, 43 L.Ed.2d 1 (1975).
. It has been observed that “the intention of the legislature is undiscoverable in any real sense. . . . The chances that of several hundred men each will have exactly the same determinate situation in mind as possible reductions of a given determinable, are infinitesimally small.” Radin, Statutory Interpretation, 43 Harv.L.Rev. 863, 870 (1930). But cf. Landis, A Note on “Statutory Interpretation," 43 Harv. L.Rev. 886 (1930).
. Justice Jackson’s memorable expression of this view bears repeating:
[T]here are practical reasons why we should accept whenever possible the meaning which an enactment reveals on its face. Laws are intended for all of our people to live by; and the people go to law offices to learn what their rights under those laws are. Here is a controversy which affects every little merchant in many States. Aside from a few offices in the larger cities, the materials of legislative history are not available to the lawyer who can afford neither the cost of acquisition, the cost of housing, or the cost of repeatedly examining the whole congressional history. Moreover, if he could, he would not know any way of anticipating what would impress enough members of the Court to be controlling. To accept legislative debates to modify statutory provisions is to make the law inaccessible to a large part of the country.
Schwegmann Bros. v. Calvert Distillers Corp., 341 U.S. 384, 396-397, 71 S.Ct. 745, 751, 95 L.Ed. 1035, 1049 (1951) (concurring opinion). See also O. W. Holmes, Collected Legal Papers 207 (1920) (“we do not inquire what the legislature meant; we only ask what the statute means”).
. See, e.g., Flora v. United States, 357 U.S. 63, 65, 78 S.Ct. 1079, 1081, 2 L.Ed.2d 1165, 1167 (1958); Browder v. United States, 312 U.S. 335, 338, 61 S.Ct. 599, 601, 85 L.Ed. 862, 865 (1941); AFL-CIO v. Marshall, 187 U.S.App.D.C. 121, 127, 570 F.2d 1030, 1036 (1978).
. Though not necessarily controlling, a section’s caption is some evidence of the intended congressional scheme. See Lan Jen Chu v. Commissioner of Internal Revenue, 486 F.2d 696, 700 (1st Cir. 1973); First Bank & Trust Co. v. Feuquay, 405 F.2d 990, 993 (6th Cir. 1969); White v. Chicago, B & Q R. R., 417 F.2d 941, 948 (8th Cir. 1969).
. § 168, 91 Stat. 740, 42 U.S.C.A. § 7478 (1978).
. “The word ‘shall’ is the language of command in a statute . .” Association of Am. R.R. v. Costle, 183 U.S.App.D.C. 362, 364, 562 F.2d 1310, 1312 (1977). See Union Elec. Co. v. EPA, 427 U.S. 246, 257, 96 S.Ct. 2518, 2525, 49 L.Ed.2d 474, 483 (1976).
. This follows from the language of § 168(a) itself, see text accompanying note 16 supra, and is not dependent on adoption of the maxim expressio unius est exclusio alterius. See National Petroleum Refiners Ass’n v. FTC, 157 U.S.App.D.C. 83, 87, 482 F.2d 672, 676 (1973), cert. denied, 415 U.S. 951, 94 S.Ct. 1475, 39 L.Ed.2d 567 (1974).
. Maj. Op., 195 U.S.App.D.C., at 47-48, 600 F.2d 861-862.
. 42 U.S.C.A. § 7401 note (1978).
. See, e.g., Brief of Sept. 25, 1978, for Environmental Groups 4-13.
. 42 U.S.C.A. § 7478(a) (1978); see notes 36-37 infra and accompanying text.
. Train v. Natural Resources Defense Council, 421 U.S. 60, 79, 95 S.Ct. 1470, 1481-1482, 43 L.Ed.2d 731, 745-746 (1975) (emphasis in original) (footnote omitted).
. 42 U.S.C.A. § 7410(a)(2) (1978).
. 42 U.S.C.A. § 7410(a)(2)(B), (D), (E), & (J) (1978).
. 42 U.S.C.A. § 7471 (1978).
. See, e.g., Brief of Sept. 25, 1978, for Environmental Groups 13-17.
. 42 U.S.C.A. § 7410(c) (1978) in part provides:
The Administrator shall, after consideration of any State hearing record, promptly prepare and publish proposed regulations setting forth an implementation plan, or portion thereof, for a State if—
(A) the State fails to submit an implementation plan which meets the requirements of this section,
(B) the plan, or any portion thereof, submitted for such State is determined by the Administrator not to be in accordance with the requirements of this section, or
(C) the State fails, within 60 days after notification by the Administrator or such longer period as he may prescribe, to revise an implementation plan as required pursuant to a provision of its plan referred to in subsection (a)(2)(H) of this section.
. Maj. Op., 195 U.S.App.D.C., at 51, 600 F.2d at 865.
. See note 28 supra.
. See note 28 supra.
. 42 U.S.C.A. § 7401 note (1978).
. 43 Fed.Reg. 26380, 26388 (June 19, 1978).
. Section 167 provides:
The Administrator shall, and a State may take such measures, including issuance of an order, or seeking injunctive relief, as necessary to prevent the construction of a major emitting facility which does not conform to the requirements of this part, or which is proposed to be constructed in any area included in the list promulgated pursuant to paragraph (1)(D) or (E) of subsection (d) of section 107 of this Act and which is not subject to an implementation plan which meets the requirements of this part.
91 Stat. 740, 42 U.S.C.A. § 7477 (1978).
. Maj. Op., 195 U.S.App.D.C., at 51-52, 600 F.2d at 865-866.
. 42 U.S.C.A. § 7478(a) (1978), quoted in text accompanying note 16 supra.
. 42 U.S.C.A. § 7410(d) (1978).
. 42 U.S.C.A. § 7478(b) (1978), quoted in text accompanying note 16 supra.
. 42 U.S.C.A. § 7479(2)(A) (1978) provides: [T]he term “commenced” as applied to construction of a major emitting facility means that the owner or operator has obtained all necessary preconstruction approvals or permits required by Federal, State, or local air pollution emissions and air quality laws or regulations and either has (i) begun, or caused to begin, a continuous program of physical on-site construction of the facility or (ii) entered into binding agreements or contractual obligations, which cannot be canceled or modified without substantial loss to the owner or operator, to undertake a program of construction of the facility to be completed within a reasonable time.
. See, e.g., United States v. Menasche, 348 U.S. 528, 536-537, 75 S.Ct. 513, 518-519, 99 L.Ed. 615, 623 (1955).
. A presumption against this imputation seems to undergird such principles of statutory construction as expressio unius est exclusio alterius. See, e.g., Botany Worsted Mills v. United States, 278 U.S. 282, 288-289, 49 S.Ct. 129, 131-132, 73 L.Ed. 379, 385 (1929). See also Vroon v. Templin, 278 F.2d 345, 348-349 (4th Cir. 1960) (“[w]e do not think it permissible to construe a statute on the basis of a mere surmise as to what the Legislature intended and to assume that it was only by inadvertance that it failed to state something other than what it plainly stated”).
. See notes 91-94 infra and accompanying text.
. § 165(a), 91 Stat. 735, 42 U.S.C.A. § 7475(a) (1978).
. Id.
. 42 U.S.C.A. § 7479(2)(A) (1978), quoted supra note 39.
. 42 U.S.C.A. § 7475(a) (1978) (emphasis supplied), quoted in relevant part in text accompanying note 44 supra.
. See 42 U.S.C.A. §§ 7470-7491 (1978).
. § 161, 91 Stat. 731, 42 U.S.C.A. § 7471 (1978).
. 42 U.S.C.A. § 7407(d)(1) (1978).
. 42 U.S.C.A. § 7407(d)(2) (1978).
. 43 Fed.Reg. 8962-9059 (March 3, 1978).
. Maj. Op., 195 U.S.App.D.C. at 48, 600 F.2d at 862; e.g., Brief of Sept. 25, 1978, for Environmental Groups 21-24.
. Maj. Op., 195 U.S.App.D.C. at 48, 600 F.2d at 862 (footnote omitted).
. § 163(b), 91 Stat. 732, 42 U.S.C.A. § 7473(b) (1978).
. Id
. 42 U.S.C.A. § 7407(d) (1978).
. 42 U.S.C.A. § 7478(b) (1978), quoted in text accompanying note 16 supra.
. 40 C.F.R. § 52.21(c) (1977).
. 40 C.F.R. § 52.21(c)(3)(i) (1977).
. Maj. Op., 195 U.S.App.D.C. at 49, 600 F.2d at 863, (emphasis in original).
. Id.
. § 165(e)(1), 91 Stat. 738, 42 U.S.C.A. § 7475(e)(1) (1978).
. See § 165(e)(3), 91 Stat. 738, 42 U.S.C.A. § 7475(e)(3) (1978) (giving EPA six months to promulgate the necessary regulations).
. Maj. Op., 195 U.S.App.D.C. at 49, 600 F.2d at 863.
. See 42 U.S.C.A. § 7479(2)(A) (1978), quoted supra note 39.
. Maj. Op., 195 U.S.App.D.C. at 52, 600 F.2d at 866.
. S. 252, 95th Cong., 1st Sess. (1977).
. H.R. 6161, 95th Cong., 1st Sess. (1977).
. S. 252, 95th Cong., 1st Sess. § 5(a) (1977) (amending § 110(a)(1) of the Clean Air Act).
. S. 252, 95th Cong., 1st Sess. § 6 (1977) (adding § 110(g)(4) to the Clean Air Act).
. Id.
. See, e.g., S. Rep. No. 127, 95th Cong., 1st Sess., at 29 (1977):
During hearings in 1974 and 1975 the committee was urged to clarify and resolve this issue through legislation, rather than leaving the matter to the courts. This section provides the statutory substance to the more general language in section 101(b) of the act, which articulates the concept of the prevention of significant deterioration. The committee intends in this new subsection 110(g) to completely define the requirements of the Clean Air Act to prevent significant deterioration.
. Sierra Club v. Ruckelshaus, 344 F.Supp. 253 (D.D.C.1972), aff'd per curiam, 4 E.R.C. 1815 (D.C. Cir. 1972), aff'd by an equally divided Court, sub nom. Fri v. Sierra Club, 412 U.S. 541, 93 S.Ct. 2770, 37 L.Ed.2d 140 (1973). See also Sierra Club v. EPA, 176 U.S.App.D.C. 335, 540 F.2d 1114 (1976), vacated and remanded for further consideration in light of Clean Air Act Amendments of 1977 sub nom. Montana Power Co., v. EPA, 434 U.S. 809, 98 S.Ct. 42, 54 L.Ed.2d 66 (1977).
. 40 C.F.R. § 52.21(d)(1) (1975).
. 40 C.F.R. § 52.21(b)(7) (1975).
. S. Rep. No. 127, 95th Cong., 1st Sess. 33 (1977).
. S. 252, 95th Cong., 1st Sess. § 6 (1977) (adding § 110(g)(6)(C) to the Clean Air Act).
. 42 U.S.C.A. § 7479(2)(A) (1978), quoted supra note 39.
. S. 252, 95th Cong., 1st Sess. § 6 (1977) (adding § 110(g)(6)(C) to the Clean Air Act).
. S. 252, 95th Cong., 1st Sess. § 6 (1977) (adding § 110(g)(7)(A) to the Clean Air Act).
. For those facilities on which construction was commenced after June 1, 1975, but prior to enactment of the 1977 amendments, the applicable PSD standards would be set out in EPA’s preexisting regulations, see note 79 supra and accompanying text; for those commenced after enactment, the statute’s requirements would govern. See note 80 supra and accompanying text.
. H.R. 6161, 95th Cong., 1st Sess. (1977).
. H.R. 6161, 95th Cong., 1st Sess. § 119 (1977) (adding § 110(g) to the Clean Air Act). This provision was substantially adopted as § 406(d)(2) of the Clean Air Act Amendments of 1977. 42 U.S.C.A. § 7401 note (1978). I agree with the court that § 406 does not materially advance resolution of the instant controversy. Maj. Op., 195 U.S.App.D.C. at 47, 50-51, 600 F.2d at 861, 864-865.
. H.R. 6161, 95th Cong., 1st Sess. § 108(a) (1977) (adding § 160 to the Clean Air Act).
. H.R. 6161, 95th Cong., 1st Sess. § 108(a) (1977) (adding § 160(h) to the Clean Air Act).
. H.R. Rep. No. 294, 95th Cong., 1st Sess. 171 (1977). See note 15 supra.
. H.R. Rep. No. 294, 95th Cong., 1st Sess. 171-172 (1977).
. See note 85 supra and accompanying text.
. 42 U.S.C.A. § 7478 (1978), quoted in text accompanying note 16 supra.
. The sections made immediately applicable establish the new allowable increments, provide for mandatory Class I classification of certain areas, and prohibit reclassification of certain areas to Class III. See 42 U.S.C.A. §§ 7472(a), 7473(b) and 7474(a) (1978).
. See note 79 supra and accompanying text.
. 42 U.S.C.A. § 7478(b) (1978), quoted in text accompanying note 16 supra.
. See notes 70-79 supra and accompanying text.
. See notes 38-42 supra and accompanying text.
. See notes 70-71 supra and accompanying text.
. 42 U.S.C.A. § 7475(a) (1978), quoted in part in text accompanying note 44 supra.
. See notes 74-78 supra and accompanying text.
. See notes 74-78 supra and accompanying text.
. See text accompanying note 74 supra.
. See text accompanying note 79 supra.
. See 42 U.S.C.A. § 7475(a) (1978), quoted in part in text accompanying note 44 supra.
. Quoted in text accompanying note 80 supra.
. H.R. 6161, 95th Cong., 1st Sess. § 108(a) (1977) (adding § 160(h) to the Clean Air Act), quoted in text accompanying note 85 supra.
. H.R. Rep. No. 294, 95th Cong., 1st Sess. 171-172 (1977), quoted in text accompanying note 87 supra.
. S. 252, 95th Cong., 1st Sess. § 6 (1977) (adding § 110(g)(7)(A) to Clean Air Act), quoted in text accompanying note 80 supra.
. See notes 70-79 supra and accompanying text.
. Unlike the majority, Maj. Op., 195 U.S.App.D.C. at 53-54, 600 F.2d at 867-868, I accord no decisional weight to the post-enactment statements of the sponsors of the 1977 Act. Regional Rail Reorganization Act Cases, 419 U.S. 102, 132, 95 S.Ct. 335, 353, 42 L.Ed.2d 320, 347 (1974); National Woodwork Mfrs. Ass'n v. NLRB, 386 U.S. 612, 634 n.34, 87 S.Ct. 1250, 1265 n.34, 18 L.Ed.2d 357, 375 n.34 (1967); Aparacor, Inc. v. United States, 571 F.2d 552, 556-557 (Ct.Cl. en banc 1978).
. 332 U.S. 480, 68 S.Ct. 174, 92 L.Ed. 88 (1947). See Sturges v. Crowninshield, 17 U.S. (4 Wheat.) 122, 202, 4 L.Ed. 529, 550 (1819) (“[w]here words conflict with each other, where the different clauses of an instrument bear upon each other, and would be inconsistent, unless the natural and common import of words be varied, construction becomes necessary, and a departure from the obvious meaning of words is justifiable”). See also FPC v. Panhandle E. Pipe Line Co., 337 U.S. 498, 514, 69 S.Ct. 1251, 1260, 93 L.Ed. 1499, 1509 (1949) (“[i]f possible all sections of the Act must be reconciled so as to produce a symmetrical whole”); cases cited supra note 10.
. 40 Stat. 411 (1917).
. 55 Stat. 839 (1941).
. 50 U.S.C.App. § 616 (Supp. V 1946) (emphasis supplied).
. 50 U.S.C-App. § 9(a) (1940).
. 332 U.S. at 486-487, 68 S.Ct. at 176-177, 92 L.Ed. at 92-93.
. Id. at 488, 68 S.Ct. at 178, 92 L.Ed. at 94.
. See Parts I, II supra. As the court’s opinion indicates, EPA’s interpretation of §§ 165(a) and 168 has varied with time and political pressure. Maj. Op., 195 U.S.App.D.C. at 40-42, 600 F.2d at 854 856. While ordinarily an agency’s construction of the statute it is charged with administering is entitled to deference, this latitude “is not a license to construe statutory language in any manner whatever [or] to conjure up powers with no clear antecedents in statute or judicial construction . .” National Ass'n of Regulatory Util. Comm'rs v. FCC, 174 U.S.App.D.C. 374, 391, 533 F.2d 601, 618 (1976).