Tier 2 Study of Vehicle Emissions - The Statutory Mandate
Clean Air Act Subsection 202(i)
"(i) Phase II Study for Certain Light-Duty Vehicles and Light-Duty
Trucks.--(1) The Administrator, with the participation of the Office of
Technology Assessment, shall study whether or not further reductions in
emissions from light-duty vehicles and light-duty trucks should be
required pursuant to this title. The study shall consider whether to
establish with respect to model years commencing after January 1, 2003,
the standards and useful life period for gasoline and diesel-fueled light-
duty vehicles and light-duty trucks with a loaded vehicle weight (LVW) of
3,750 lbs. or less specified in the following table:
"TABLE 3
PENDING EMISSION STANDARDS
FOR GASOLINE AND DIESEL FUELED LIGHT-DUTY VEHICLES AND
LIGHT-DUTY TRUCKS 3,750 LBS. LVW OR LESS
Pollutant Emission Level*
-----------------------------
NMHC................0.125 gpm
NOx...................0.2 gpm
CO....................1.7 gpm
-----------------------------
* Emission levels are expressed in grams per mile (GPM). For vehicles and
engines subject to this subsection for purposes of section 202(d) and any
reference thereto, the useful life of such vehicles and engines shall be a
period of 10 years or 100,000 miles (or the equivalent), whichever first
occurs.
Such study shall also consider other standards and useful life periods
which are more stringent or less stringent than those set forth in table 3
(but more stringent than those referred to in subsections (g) and (h)).
"(2)(A) As part of the study under paragraph (1), the Administrator
shall examine the need for further reductions in emissions in order to
attain or maintain the national ambient air quality standards, taking into
consideration the waiver provisions of section 209(b).As part of such
study,the Administrator shall also examine--
"(i) the availability of technology (including the costs thereof), in the
case of light-duty vehicles and light-duty trucks with a loaded vehicle
weight (LVW) of 3,750 lbs. or less, for meeting more stringent emission
standards than those provided in subsections (g) and (h) for model years
commencing not earlier than after January 1, 2003, and not later than
model year 2006, including the lead time and safety and energy impacts of
meeting more stringent emission standards; and
"(ii) the need for, and cost effectiveness of, obtaining further
reductions in emissions from such light-duty vehicles and light-duty
trucks, taking into consideration alternative means of attaining or
maintaining the national primary ambient air quality standards pursuant
to State implementation plans and other requirements of this Act,
including their feasibility and cost effectiveness.
"(B) The Administrator shall submit a report to Congress no later than
June 1, 1997, containing the results of the study under this subsection,
including the results of the examination conducted under subparagraph (A).
Before submittal of such report the Administrator shall provide a
reasonable opportunity for public comment and shall include a summary of
such comments in the report to Congress.
"(3)(A) Based on the study under paragraph (1) the Administrator shall
determine, by rule, within 3 calendar years after the report is submitted
to Congress, but not later than December 31, 1999, whether--
"(i) there is a need for further reductions in emissions as provided in
paragraph (2)(A);
"(ii) the technology for meeting more stringent emission standards
will be available, as provided in paragraph (2)(A)(i), in the case of light-
duty vehicles and light-duty trucks with a loaded vehicle weight (LVW) of
3,750 lbs. or less, for model years commencing not earlier than January 1,
2003 and not later than model year 2006, considering the factors listed in
paragraph(2)(A)(i); and
"(iii) obtaining further reductions in emissions from such vehicles will
be needed and cost effective, taking into consideration alternatives as
provided in paragraph (2)(A)(ii).
The rulemaking under this paragraph shall commence within 3 months
after submission of the report to Congress under paragraph (2)(B).
"(B) If the Administrator determines under subparagraph (A) that--
"(i) there is no need for further reductions in emissions as provided in
paragraph (2)(A);
"(ii) the technology for meeting more stringent emission standards
will not be available as provided in paragraph(2)(A)(i), in the case of
light-duty vehicles and light-duty trucks with a loaded vehicle weight
(LVW) of 3,750 lbs. or less, for model years commencing not earlier than
January 1, 2003, and not later than model year 2006, considering the
factors listed in paragraph (2)(A)(i); or
"(iii) obtaining further reductions in emissions from such vehicles will
not be needed or cost effective, taking into consideration alternatives as
provided in paragraph (2)(A)(ii),
the Administrator shall not promulgate more stringent standards than
those in effect pursuant to subsections (g) and (h). Nothing in this
paragraph shall prohibit the Administrator from exercising the
Administrator's authority under subsection (a) to promulgate more
stringent standards for light-duty vehicles and light-duty trucks with a
loaded vehicle weight (LVW) of 3,750 lbs. or less at any other time
thereafter in accordance with subsection (a).
"(C) If the Administrator determines under subparagraph (A) that--
"(i) there is a need for further reductions in emissions as provided in
paragraph (2)(A);
"(ii) the technology for meeting more stringent emission standards
will be available, as provided in paragraph (2)(A)(i), in the case of light-
duty vehicles and light-duty trucks with a loaded vehicle weight (LVW) of
3,750 lbs. or less, for model years commencing not earlier than January 1,
2003, and not later than model year 2006, considering the factors listed
in paragraph(2)(A)(i); and
"(iii) obtaining further reductions in emissions from such vehicles will
be needed and cost effective, taking into consideration alternatives as
provided in paragraph (2)(A)(ii),
the Administrator shall either promulgate the standards (and useful life
periods) set forth in Table 3 in paragraph (1) or promulgate alternative
standards (and useful life periods) which are more stringent than those
referred to in subsections (g) and (h). Any such standards (or useful life
periods) promulgated by the Administrator shall take effect with respect
to any such vehicles or engines no earlier than the model year 2003 but
not later than model year 2006, as determined by the Administrator in the
rule.
"(D) Nothing in this paragraph shall be construed by the Administrator
or by a court as a presumption that any standards (or useful life period)
set forth in Table 3 shall be promulgated in the rulemaking required under
this paragraph. The action required of the Administrator in accordance
with this paragraph shall be treated as a nondiscretionary duty for
purposes of section 304(a)(2) (relating to citizen suits).
"(E) Unless the Administrator determines not to promulgate more
stringent standards as provided in subparagraph (B) or to postpone the
effective date of standards referred to in Table 3 in paragraph (1) or to
establish alternative standards as provided in subparagraph (C), effective
with respect to model years commencing after January 1, 2003, the
regulations under subsection (a) applicable to emissions of nonmethane
hydrocarbons (NMHC), oxides of nitrogen (NOx), and carbon monoxide (CO)
from motor vehicles and motor vehicle engines in the classes specified in
Table 3 in paragraph (1) above shall contain standards which provide that
emissions may not exceed the pending emission levels specified in Table 3
in paragraph (1).".
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