29 



required by paragraph (1)(A) with respect to such 

 manufacturer. The Administrator shall make his 

 determination with respect to any such application 

 within 60 days. If he determines, in accordance 

 with the provisions of this subsection, that such 

 suspension should be granted, he shall simultane- 

 ously with such determination prescribe by regula- 

 tion interim emission standards which shall apply 

 (in lieu of the standards required to be prescribed 

 by paragraph (1) (A) ) to emissions of carbon mon- 

 oxide or hydrocarbons (or both) from such ve- 

 hicles and engines manufactured during model year 

 1975. 



(B) At any time after January 1, 1973, any manu- 

 facturer may file with the Administrator an ap- 

 plication requesting the suspension for one year 

 only of the effective date of any emission standard 

 required by paragraph (1) (B) with respect to such 

 manufacturer. The Administrator shall make his 

 determination with respect to any such application 

 within 60 days. If he determines, in accordance with 

 the provisions of this subsection, that such sus- 

 pension should be granted, he shall simultaneously 

 with such determination prescribe by regulation 

 interim emission standards which shall apply (in 

 lieu of the standards required to be prescribed by 

 paragraph (1) (B) ) to emissions of oxides of nitrogen 

 from such vehicles and engines manufactured dur- 

 ing model year 1976. 



(C) Any interim standards prescribed under this 

 paragraph shall reflect the greatest degree of emis- 

 sion control which is achievable by application of 

 technology which the Administrator determines is 

 available, giving appropriate consideration to the 

 cost of applying such technology within the period 

 of time available to manufacturers. 



(D) Within 60 days after receipt of the applica- 

 tion for any such suspension, and after public hear- 

 ing, the Administrator shall issue a decision grant- 

 ing or refusing such suspension. The Administrator 

 shall grant such suspension only if he determines 

 that (1) such suspension is essential to the public 

 Interest or the public health and welfare of the 

 United States, (11) all good faith efTorte have been 

 made to meet the standards established by this 

 subsection. (iU) the applicant has established that 

 effective control technology, processes, operating 

 methods, or other alternatives are not available 

 or have not been available for a sufiBclent period of 

 time to achieve compliance prior to the effective 

 date of such standards, and (Iv) the study and in- 

 vestigation of the National Academy of Sciences 

 conducted pursuant to subsection (c) of this section 

 and other information available to him has not 

 indicated that technology, processes, or other alter- 

 natives are available to meet such standtu-ds. 



(E) Nothing in this paragraph shall extend the 

 effective date of any emission standard required to 

 be prescribed imder this subsection for more than 

 one year. 



(c) Feasibility study and investigation by National 

 Academy of Sciences; reports to Administrator 

 and Congress; availability of information. 

 (1) The Administrator shall undertake to enter 



Into appropriate arrangements with the National 



Academy of Sciences to conduct a comprehensive 

 study and investigation of the technological feasi- 

 bility of meeting the emissions standards required 

 to be prescribed by the Administrator by subeeotion 

 (b) of this section. 



(2) Of the funds authorized to be appropriated 

 to the Administrator by this chapter, such amounts 

 as are required shall be available to carry out the 

 study and Investigation authorized by paragraph 

 (1) of this subsection. 



( 3 ) In entering into any arrangement with the Na- 

 tional Academy of Sciences for conducting the study 

 and investigation authorized by paragraph (1) of 

 this subsection, the Administrator shall request the 

 National Academy of Sciences to submit semlarmual 

 reports on the progress of its study and investigation 

 to the Administrator and the Congress, beginning 

 not later than July 1, 1971, and continuing until 

 such study and investigation Is completed. 



(4) The Administrator shall furnish to such 

 Academy at its request any information which the 

 Academy deems necessary for the purpose of con- 

 ducting the Investigation and study authorized by 

 paragraph (1) of this subsection. For the purpose of 

 furnishing such Information, the Administrator may 

 use any authority he has under this chapter (A) to 

 obtain information from any person, and (B) to 

 require such person to conduct such tests, keep 

 such records, and make such reports respecting re- 

 search or other activities conducted by such person 

 as may be reasonabily necessary to carry out this 

 subsection. 



(d) Useful life of vehicles. 



The Administrator shall prescribe regulations 

 under which the useful life of vehicles and engines 

 shall be determined for purposes of subsection (a) 

 (1) of this section and section 1857f-5a of this title. 

 Such regulations shall provide that useful life 

 shall— 



(1) in the case of light duty vehicles and light 

 duty vehicle engines, be a period of use of five 

 years or fifty thousand miles (or the equivalent) , 

 whichever first occurs; and 



(2) in the case of any other motor vehicle or 

 motor vehicle engine, be a period of use set forth 

 in paragraph (1) unless the Administrator deter- 

 mines that a period of use of greater duration or 

 mileage is appropriate. 



(e) New power sources or propulsion systems. 



In the event of a new power source or propulsion 

 system for new motor vehicles or new motor vehicle 

 engines is submitted for certification pursuant to 

 section 1857f-5(a) of this title, the Administrator 

 may postpone certification until he has prescribed 

 standards for any air pollutants emitted by such 

 vehicle or engine which cause or contribute to, or 

 are likely to cause or contribute to, air pollution 

 which endangers the public health or welfare but 

 for which standards have not been prescribed under 

 subsection (a) of this section. (July 14, 1955, ch. 

 360, title II. J 202, as added Oct. 20, 1965, Pub. L. 

 89-272, title I, § 101(8), 79 Stat. 992, and amended 

 Nov. 21. 1967. Pub. L. 90-148. { 2. 81 Stat. 499; Dec. 

 31. 1970, Pub. L. 91-604, § 6(a), 84 Stat. 1690.) 



