[Federal Register Volume 76, Number 179 (Thursday, September 15, 2011)]
[Rules and Regulations]
[Pages 57106-57513]
[FR Doc No: 2011-20740]

Vol. 76

Thursday,

No. 179

September 15, 2011

Part II

Environmental Protection Agency

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40 CFR Parts 85, 86, 600, et al.

Department of Transportation

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National Highway Traffic Safety Administration

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49 CFR Parts 523, 534, and 535

Greenhouse Gas Emissions Standards and Fuel Efficiency Standards for
Medium- and Heavy-Duty Engines and Vehicles; Final Rule

Federal Register / Vol. 76, No. 179 / Thursday, September 15, 2011 /
Rules and Regulations

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ENVIRONMENTAL PROTECTION AGENCY

40 CFR Parts 85, 86, 600, 1033, 1036, 1037, 1039, 1065, 1066, and
1068

DEPARTMENT OF TRANSPORTATION

National Highway Traffic Safety Administration

49 CFR Parts 523, 534, and 535

[EPA-HQ-OAR-2010-0162; NHTSA-2010-0079; FRL-9455-1]
RIN 2060-AP61; 2127-AK74

Greenhouse Gas Emissions Standards and Fuel Efficiency Standards
for Medium- and Heavy-Duty Engines and Vehicles

AGENCY: Environmental Protection Agency (EPA) and National Highway
Traffic Safety Administration (NHTSA), DOT.

ACTION: Final Rules.

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SUMMARY: EPA and NHTSA, on behalf of the Department of Transportation,
are each finalizing rules to establish a comprehensive Heavy-Duty
National Program that will reduce greenhouse gas emissions and fuel
consumption for on-road heavy-duty vehicles, responding to the
President's directive on May 21, 2010, to take coordinated steps to
produce a new generation of clean vehicles. NHTSA's final fuel
consumption standards and EPA's final carbon dioxide (CO2)
emissions standards are tailored to each of three regulatory categories
of heavy-duty vehicles: Combination Tractors; Heavy-duty Pickup Trucks
and Vans; and Vocational Vehicles. The rules include separate standards
for the engines that power combination tractors and vocational
vehicles. Certain rules are exclusive to the EPA program. These include
EPA's final hydrofluorocarbon standards to control leakage from air
conditioning systems in combination tractors, and pickup trucks and
vans. These also include EPA's final nitrous oxide (N2O) and
methane (CH4) emissions standards that apply to all heavy-
duty engines, pickup trucks and vans.
    EPA's final greenhouse gas emission standards under the Clean Air
Act will begin with model year 2014. NHTSA's final fuel consumption
standards under the Energy Independence and Security Act of 2007 will
be voluntary in model years 2014 and 2015, becoming mandatory with
model year 2016 for most regulatory categories. Commercial trailers are
not regulated in this phase of the Heavy-Duty National Program.
    The agencies estimate that the combined standards will reduce
CO2 emissions by approximately 270 million metric tons and
save 530 million barrels of oil over the life of vehicles sold during
the 2014 through 2018 model years, providing over $7 billion in net
societal benefits, and $49 billion in net societal benefits when
private fuel savings are considered.
    EPA is also finalizing provisions allowing light-duty vehicle
manufacturers to use CO2 credits to meet the light-duty
vehicle N2O and CH4 standards, technical
amendments to the fuel economy provisions for light-duty vehicles, and
a technical amendment to the criteria pollutant emissions requirements
for certain switch locomotives.

DATES: These final rules are effective on November 14, 2011. The
incorporation by reference of certain publications listed in this
regulation is approved by the Director of the Federal Register as of
November 14, 2011.

ADDRESSES: EPA and NHTSA have established dockets for this action under
Docket ID No. EPA-HQ-OAR-2010-0162 and NHTSA-2010-0079, respectively.
All documents in the docket are listed on the http://www.regulations.gov Web site. Although listed in the index, some
information is not publicly available, e.g., confidential business
information or other information whose disclosure is restricted by
statute. Certain other material, such as copyrighted material, is not
placed on the Internet and will be publicly available only in hard copy
form. Publicly available docket materials are available either
electronically through http://www.regulations.gov or in hard copy at
the following locations: EPA: EPA Docket Center, EPA/DC, EPA West
Building, 1301 Constitution Ave., NW., Room 3334, Washington, DC. The
Public Reading Room is open from 8:30 a.m. to 4:30 p.m., Monday through
Friday, excluding legal holidays. The telephone number for the Public
Reading Room is<PHONE_NUMBER>, and the telephone number for the Air
Docket is<PHONE_NUMBER>. NHTSA: Docket Management Facility, M-30, U.S.
Department of Transportation, West Building, Ground Floor, Rm. W12-140,
1200 New Jersey Avenue, SE., Washington, DC 20590. The Docket
Management Facility is open between 9 a.m. and 5 p.m. Eastern Time,
Monday through Friday, except Federal holidays.

FOR FURTHER INFORMATION CONTACT: NHTSA: Lily Smith, Office of Chief
Counsel, National Highway Traffic Safety Administration, 1200 New
Jersey Avenue, SE., Washington, DC 20590. Telephone:<PHONE_NUMBER>.
EPA: Lauren Steele, Office of Transportation and Air Quality,
Assessment and Standards Division (ASD), Environmental Protection
Agency, 2000 Traverwood Drive, Ann Arbor, MI 48105; telephone number:
(734) 214-4788; fax number:<PHONE_NUMBER>; e-mail address:
<EMAIL_ADDRESS>or contact the Office of Transportation and Air
Quality at<EMAIL_ADDRESS>
SUPPLEMENTARY INFORMATION:

A. Does this action apply to me?

    This action affects companies that manufacture, sell, or import
into the United States new heavy-duty engines and new Class 2b through
8 trucks, including combination tractors, school and transit buses,
vocational vehicles such as utility service trucks, as well as \3/4\-
ton and 1-ton pickup trucks and vans. The heavy-duty category
incorporates all motor vehicles with a gross vehicle weight rating of
8,500 pounds or greater, and the engines that power them, except for
medium-duty passenger vehicles already covered by the greenhouse gas
emissions standards and corporate average fuel economy standards issued
for light-duty model year 2012-2016 vehicles. Regulated categories and
entities include the following:

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                                                        Examples of
           Category              NAICS Code \a\    potentially affected
                                                         entities
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Industry......................            336111  Motor Vehicle
                                          336112   Manufacturers, Engine
                                                   and Truck
                                                   Manufacturers.
                                          336120
Industry......................            541514  Commercial Importers
                                          811112   of Vehicles and
                                                   Vehicle Components.
                                          811198
Industry......................            336111  Alternative Fuel
                                                   Vehicle Converters.
                                          336112

                                          422720
                                          454312
                                          541514
                                          541690
                                          811198
Industry......................            333618  Manufacturers,
                                          336510   remanufacturers and
                                                   importers of
                                                   locomotives and
                                                   locomotive engines.
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Note:
\a\ North American Industry Classification System (NAICS).

    This table is not intended to be exhaustive, but rather provides a
guide for readers regarding entities likely covered by these rules.
This table lists the types of entities that the agencies are aware may
be regulated by this action. Other types of entities not listed in the
table could also be regulated. To determine whether your activities are
regulated by this action, you should carefully examine the
applicability criteria in the referenced regulations. You may direct
questions regarding the applicability of this action to the persons
listed in the preceding FOR FURTHER INFORMATION CONTACT section.

Table of Contents

A. Does this action apply to me?
I. Overview
    A. Introduction
    B. Building Blocks of the Heavy-Duty National Program
    C. Summary of the Final EPA and NHTSA HD National Program
    D. Summary of Costs and Benefits of the HD National Program
    E. Program Flexibilities
    F. EPA and NHTSA Statutory Authorities
    G. Future HD GHG and Fuel Consumption Rulemakings
II. Final GHG and Fuel Consumption Standards for Heavy-Duty Engines
and Vehicles
    A. What vehicles will be affected?
    B. Class 7 and 8 Combination Tractors
    C. Heavy-Duty Pickup Trucks and Vans
    D. Class 2b-8 Vocational Vehicles
    E. Other Standards
III. Feasibility Assessments and Conclusions
    A. Class 7-8 Combination Tractor
    B. Heavy-Duty Pickup Trucks and Vans
    C. Class 2b-8 Vocational Vehicles
IV. Final Regulatory Flexibility Provisions
    A. Averaging, Banking, and Trading Program
    B. Additional Flexibility Provisions
V. NHTSA and EPA Compliance, Certification, and Enforcement
Provisions
    A. Overview
    B. Heavy-Duty Pickup Trucks and Vans
    C. Heavy-Duty Engines
    D. Class 7 and 8 Combination Tractors
    E. Class 2b-8 Vocational Vehicles
    F. General Regulatory Provisions
    G. Penalties
VI. How will this program impact fuel consumption, GHG emissions,
and climate change?
    A. What methodologies did the agencies use to project GHG
emissions and fuel consumption impacts?
    B. MOVES Analysis
    C. What are the projected reductions in fuel consumption and GHG
emissions?
    D. Overview of Climate Change Impacts From GHG Emissions
    E. Changes in Atmospheric CO2 Concentrations, Global
Mean Temperature, Sea Level Rise, and Ocean pH Associated With the
Program's GHG Emissions Reductions
VII. How will this final action impact non-ghg emissions and their
associated effects?
    A. Emissions Inventory Impacts
    B. Health Effects of Non-GHG Pollutants
    C. Environmental Effects of Non-GHG Pollutants
    D. Air Quality Impacts of Non-GHG Pollutants
VIII. What are the agencies' estimated cost, economic, and other
impacts of the final program?
    A. Conceptual Framework for Evaluating Impacts
    B. Costs Associated With the Final Program
    C. Indirect Cost Multipliers
    D. Cost per Ton of Emissions Reductions
    E. Impacts of Reduction in Fuel Consumption
    F. Class Shifting and Fleet Turnover Impacts
    G. Benefits of Reducing CO2 Emissions
    H. Non-GHG Health and Environmental Impacts
    I. Energy Security Impacts
    J. Other Impacts
    K. The Effect of Safety Standards and Voluntary Safety
Improvements on Vehicle Weight
    L. Summary of Costs and Benefits
    M. Employment Impacts
IX. Analysis of the Alternatives
    A. What are the alternatives that the agencies considered?
    B. How do these alternatives compare in overall GHG emissions
reductions and fuel efficiency and cost?
    C. What is the agencies' decision regarding trailer standards?
X. Public Participation
XI. NHTSA's Record of Decision
    A. The Agency's Decision
    B. Alternatives Considered by NHTSA in Reaching Its Decision,
Including the Environmentally Preferable Alternative
    C. Factors Balanced by NHTSA in Making Its Decision
    D. How the Factors and Considerations Balanced by NHTSA Entered
Into Its Decision
    E. The Agency's Preferences Among Alternatives Based on Relevant
Factors, Including Economic and Technical Considerations and Agency
Statutory Missions
    F. Mitigation
XII. Statutory and Executive Order Reviews
XIII. Statutory Provisions and Legal Authority
    A. EPA
    B. NHTSA

I. Overview

A. Introduction

    EPA and NHTSA (``the agencies'') are announcing a first-ever
program to reduce greenhouse gas (GHG) emissions and fuel consumption
in the heavy-duty highway vehicle sector. This broad sector--ranging
from large pickups to sleeper-cab tractors--together represent the
second largest contributor to oil consumption and GHG emissions from
the mobile source sector, after light-duty passenger cars and trucks.
These are the second joint rules issued by the agencies, following on
the April 1, 2010 standards to sharply reduce GHG emissions and fuel
consumption from MY 2012-2016 passenger cars and light trucks
(published on May 7, 2010 at 75 FR 25324).
    In a May 21, 2010 memorandum to the Administrators of EPA and NHTSA
(and the Secretaries of Transportation and Energy), the President
stated that ``America has the opportunity to lead the world in the
development of a new generation of clean cars and trucks through
innovative technologies and manufacturing that will spur economic
growth and create high-quality domestic jobs, enhance our energy
security, and improve our environment.'' 1 2 In the

May 2010 memorandum, the President specifically requested the
Administrators of EPA and NHTSA to ``immediately begin work on a joint
rulemaking under the Clean Air Act (CAA) and the Energy Independence
and Security Act of 2007 (EISA) to establish fuel efficiency and
greenhouse gas emissions standards for commercial medium-and heavy-duty
on-highway vehicles and work trucks beginning with the 2014 model year
(MY).'' In this final rulemaking, each agency is addressing this
Memorandum by adopting rules under its respective authority that
together comprise a coordinated and comprehensive HD National Program
designed to address the urgent and closely intertwined challenges of
reduction of dependence on oil, achievement of energy security, and
amelioration of global climate change.
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    \1\ Improving Energy Security, American Competitiveness and Job
Creation, and Environmental Protection Through a Transformation of
Our Nation's Fleet of Cars And Trucks,'' Issued May 21, 2010,
published at 75 FR 29399, May 26, 2010.
    \2\ The May 2010 Presidential Memorandum also directed EPA and
NHTSA, in close coordination with the California Air Resources
Board, to build on the National Program for 2012-2016 MY light-duty
vehicles by developing and proposing coordinated light-duty vehicle
standards for MY 2017-2025. The agencies have taken an initial step
in this process, releasing a Joint Notice of Intent and Initial
Joint Technical Assessment Report in September 2010 (75 FR 62739),
and a Supplemental Notice of Intent (75 FR 76337). The agencies plan
to issue a full light-duty vehicle proposal to extend the National
Program to MY 2017-2025 in September 2011.
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    At the same time, the final program will enhance American
competitiveness and job creation, benefit consumers and businesses by
reducing costs for transporting goods, and spur growth in the clean
energy sector.
    The HD National Program the agencies are finalizing today reflects
a collaborative effort between the agencies, a range of public interest
nongovernmental organizations (NGOs), the state of California and the
regulated industry. At the time of the President's announcement, a
number of major HD truck and engine manufacturers representing the vast
majority of this industry, and the California Air Resources Board
(California ARB), sent letters to EPA and NHTSA supporting the creation
of a HD National Program based on a common set of principles. In the
letters, the stakeholders committed to working with the agencies and
with other stakeholders toward a program consistent with common
principles, including:
    Increased use of existing technologies to achieve significant GHG
emissions and fuel consumption reductions;
    A program that starts in 2014 and is fully phased in by 2018;
    A program that works towards harmonization of methods for
determining a vehicle's GHG and fuel efficiency, recognizing the global
nature of the issues and the industry;
    Standards that recognize the commercial needs of the trucking
industry; and
    Incentives leading to the early introduction of advanced
technologies.
    The final rules adopted today reflect these principles. The final
HD National Program also builds on many years of heavy-duty engine and
vehicle technology development to achieve what the agencies believe is
the greatest degree of fuel consumption and GHG emission reduction
appropriate, technologically and economically feasible, and cost-
effective for model years 2014-2018. In addition to taking aggressive
steps that are reasonably possible now, based on the technological
opportunities and pathways that present themselves during these model
years, the agencies and industry will also continue learning about
emerging opportunities for this complex sector to further reduce fuel
consumption and GHG emission through future regulatory steps.
    Similarly, the agencies will participate in efforts to improve our
ability to accurately characterize the actual in-use fuel consumption
and emissions of this complex sector. As technologies progress in the
coming years and as the agencies improve the regulatory tools to
evaluate real world vehicle performance, we expect that we will develop
a second phase of regulations to reinforce these initial rules and
achieve further reductions in GHG emissions and fuel consumption
reduction for the mid- and longer-term time frame (beyond 2018). The
agencies are committed to working with all interested stakeholders in
this effort and to the extent possible working towards alignment with
similar programs being developed in Canada, Mexico, Europe, China, and
Japan. In doing so, we will continue to evaluate many of the structural
and technical decisions we are making in today's final action in the
context of new technologies and the new regulatory tools that we expect
to realize in the future.
    The regulatory program we are finalizing today is largely unchanged
from the proposal the agencies made on November 30, 2010 (See 75 FR
741512). The structure of the program and the stringency of the
standards are essentially the same as proposed. We have made a number
of changes to the testing requirements and reporting requirements to
provide greater regulatory certainty and better align the NHTSA and EPA
portions of the program. In response to comments, we have also made
some changes to the averaging, banking and trading (ABT) provisions of
the program that will make implementation of this final program more
flexible for manufacturers. We have added provisions to further
encourage the development of advanced technologies and to provide a
more straightforward mechanism to certify engines and vehicles using
innovative technologies. Finally in response to comments, we have made
some technical changes to our emissions compliance model that results
in different numeric standards for both combination tractors and
vocational vehicles to more accurately characterize emissions while
maintaining the same overall stringency and therefore expected costs
and benefits of the program.
    Heavy-duty vehicles move much of the nation's freight and carry out
numerous other tasks, including utility work, concrete delivery, fire
response, refuse collection, and many more. Heavy-duty vehicles are
primarily powered by diesel engines, although about 37 percent of these
vehicles are powered by gasoline engines.\3\ Heavy-duty trucks \4\ have
long been an important part of the goods movement infrastructure in
this country and have experienced significant growth over the last
decade related to increased imports and exports of finished goods and
increased shipping of finished goods to homes through Internet
purchases.
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    \3\ References in this preamble to ``gasoline'' engines (and the
vehicles powered by them) generally include other Otto-cycle engines
as well, such as those fueled by ethanol and natural gas, except in
contexts that are clearly gasoline-specific.
    \4\ In this rulemaking, EPA and NHTSA use the term ``truck'' in
a general way, referring to all categories of regulated heavy-duty
highway vehicles (including buses). As such, the term is generally
interchangeable with ``heavy-duty vehicle.''
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    The heavy-duty sector is extremely diverse in several respects,
including types of manufacturing companies involved, the range of sizes
of trucks and engines they produce, the types of work the trucks are
designed to perform, and the regulatory history of different
subcategories of vehicles and engines. The current heavy-duty fleet
encompasses vehicles from the ``18-wheeler'' combination tractors one
sees on the highway to school and transit buses, to vocational vehicles
such as utility service trucks, as well as the largest pickup trucks
and vans.
    For purposes of this preamble, the term ``heavy-duty'' or ``HD'' is
used to apply to all highway vehicles and engines that are not within
the range of light-duty vehicles, light-duty trucks, and medium-duty
passenger vehicles (MDPV) covered by the GHG and Corporate Average Fuel
Economy (CAFE) standards issued for MY 2012-2016.\5\ It also does not
include

motorcycles. Thus, in this rulemaking, unless specified otherwise, the
heavy-duty category incorporates all vehicles with a gross vehicle
weight rating above 8,500 pounds, and the engines that power them,
except for MDPVs.\6\
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    \5\ Light-Duty Vehicle Greenhouse Gas Emission Standards and
Corporate Average Fuel Economy Standards; Final Rule 75 FR 25323,
May 7, 2010.
    \6\ The CAA defines heavy-duty as a truck, bus or other motor
vehicles with a gross vehicle weight rating exceeding 6,000 pounds
(CAA section 202(b)(3)). The term HD as used in this action refers
to a subset of these vehicles and engines.
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    The agencies proposed to cover all segments of the heavy-duty
category above, except with respect to recreational vehicles (RVs or
motor homes). We note that the Energy Independence and Security Act of
2007 requires NHTSA to set standards for ``commercial medium- and
heavy-duty on-highway vehicles and work trucks.'' \7\ The standards
that EPA is finalizing today cover recreational on-highway vehicles,
while NHTSA proposed not to include recreational vehicles based on an
interpretation of the term ``commercial medium- and heavy-duty on-
highway commercial'' vehicles. NHTSA stated in the NPRM that
recreational vehicles are non-commercial, and therefore outside of the
term and the scope of its rule.
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    \7\ 49 U.S.C. 32902(k)(2). ``Commercial medium- and heavy-duty
on-highway vehicles'' are defined as on-highway vehicles with a
gross vehicle weight rating of 10,000 pounds or more, while ``work
trucks'' are defined as vehicles rated between 8,500 and 10,000
pounds gross vehicle weight that are not MDPVs. See 49 U.S.C.
32901(a)(7) and (a)(19).
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    Oshkosh Corporation commented that this interpretation did not
match the statutory definition of the term in EISA, which defines
``commercial medium- and heavy-duty on-highway vehicle'' by weight
only,\8\ and that therefore the agency's interpretation of the term
should be explicitly broadened to include all vehicles, and more than
only vehicles that are not engaged in interstate commerce as defined by
the Federal Motor Carrier Safety Administration in 49 CFR part 202.
Alternatively, Oshkosh suggested that if NHTSA followed the definition
provided in EISA, which makes no direct reference to the concept of
``commercial,'' there would be no logical reason to exclude RVs based
on that definition.
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    \8\ See 49 U.S.C. 32902(k)(2), Note 7 above.
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    NHTSA has considered Oshkosh's comment and reconsidered its
interpretation that effectively read words into the statutory
definition. Given the very wide variety of vehicles contained in the HD
fleet, reading those words into the definition and thereby excluding
certain types of vehicles could create illogical results, i.e.,
treating similar vehicles differently. Therefore, NHTSA will adhere to
the statutory definition contained in EISA for this rulemaking.
However, as RVs were not included by NHTSA in the proposed regulation
in the NPRM, they are not within the scope and must be excluded in
NHTSA's portion of the final program. Accordingly, NHTSA will address
this issue in the next rulemaking. However, as noted, RVs are subject
to the CO2 standards for vocational vehicles.
    Setting fuel consumption standards for the heavy-duty sector,
pursuant to NHTSA's EISA authority, will also improve our energy and
national security by reducing our dependence on foreign oil, which has
been a national objective since the first oil price shocks in the
1970s. Net petroleum imports now account for approximately 49-51
percent of U.S. petroleum consumption. World crude oil production is
highly concentrated, exacerbating the risks of supply disruptions and
price shocks as the recent unrest in North Africa and the Persian Gulf
highlights. Recently, oil prices have been over $100 per barrel,
gasoline and diesel fuel prices in excess of $4 per gallon, causing
financial hardship for many families and businesses. The export of U.S.
assets in exchange for oil imports continues to be an important
component of the historically unprecedented U.S. trade deficits.
Transportation accounts for about 72 percent of U.S. petroleum
consumption. Heavy-duty vehicles account for about 17 percent of
transportation oil use, which means that they alone account for about
12 percent of all U.S. oil consumption.\9\
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    \9\ In 2009 Source: EIA Annual Energy Outlook 2010 released May
11, 2010.
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    Setting GHG emissions standards for the heavy-duty sector will help
to ameliorate climate change. The EPA Administrator found after a
thorough examination of the scientific evidence on the causes and
impact of current and future climate change, and careful review of
public comments, that the science compellingly supports a positive
finding that atmospheric concentrations of six greenhouse gases taken
in combination result in air pollution which may reasonably be
anticipated to endanger both public health and welfare and that the
combined emissions of these greenhouse gases from new motor vehicles
and engines contributes to the greenhouse gas air pollution that
endangers public health and welfare. In her finding, the Administrator
carefully studied and relied heavily upon the major findings and
conclusions from the recent assessments of the U.S. Climate Change
Science Program and the U.N. Intergovernmental Panel on Climate Change.
74 FR 66496, December 15, 2009. As summarized in the Technical Support
Document for EPA's Endangerment and Cause or Contribute Findings under
section 202(a) of the Clean Air Act, anthropogenic emissions of GHGs
are very likely (a 90 to 99 percent probability) the cause of most of
the observed global warming over the last 50 years.\10\ Primary GHGs of
concern are carbon dioxide (CO2), methane (CH4),
nitrous oxide (N2O), hydrofluorocarbons (HFCs),
perfluorocarbons (PFCs), and sulfur hexafluoride (SF6).
Mobile sources emitted 31 percent of all U.S. GHGs in 2007
(transportation sources, which do not include certain off-highway
sources, account for 28 percent) and have been the fastest-growing
source of U.S. GHGs since 1990.\11\ Mobile sources addressed in EPA's
endangerment and contribution findings under CAA section 202(a)--light-
duty vehicles, heavy-duty trucks, buses, and motorcycles--accounted for
23 percent of all U.S. GHG emissions in 2007.\12\ Heavy-duty vehicles
emit CO2, CH4, N2O, and HFCs and are
responsible for nearly 19 percent of all mobile source GHGs (nearly 6
percent of all U.S. GHGs) and about 25 percent of section 202(a) mobile
source GHGs. For heavy-duty vehicles in 2007, CO2 emissions
represented more than 99 percent of all GHG emissions (including
HFCs).\13\
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    \10\ U.S. EPA. (2009). ``Technical Support Document for
Endangerment and Cause or Contribute Findings for Greenhouse Gases
Under Section 202(a) of the Clean Air Act'' Washington, DC,
available at Docket: EPA-HQ-OAR-2009-0171-11645, and at http://epa.gov/climatechange/endangerment.html.
    \11\ U.S. Environmental Protection Agency. 2009. Inventory of
U.S. Greenhouse Gas Emissions and Sinks: 1990-2007. EPA 430-R-09-
004. Available at http://epa.gov/climatechange/emissions/downloads09/GHG2007entire_report-508.pdf.
    \12\ See Endangerment TSD, Note 10, above, at pp. 180-194.
    \13\ U.S. Environmental Protection Agency. 2009. Inventory of
U.S. Greenhouse Gas Emissions and Sinks: See Note 11, above.
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    In developing this HD National program, the agencies have worked
with a large and diverse group of stakeholders representing truck and
engine manufacturers, trucking fleets, environmental organizations, and
states including the State of California.\14\ Further, it is our
expectation based on our ongoing work with the State of California that
the California ARB will

be able to adopt regulations equivalent in practice to those of this HD
National Program, just as it has done for past EPA regulation of heavy-
duty trucks and engines. NHTSA and EPA have been working with
California ARB to enable that outcome.
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    \14\ Pursuant to DOT Order 2100.2, NHTSA has docketed a
memorandum recording those meetings that it attended and documents
submitted by stakeholders which formed a basis for this action and
which can be made publicly available in its docket for this
rulemaking. DOT Order 2100.2 is available at http://www.reg-group.com/library/DOT2100-2.PDF.
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    In light of the industry's diversity, and consistent with the
recommendations of the National Academy of Sciences (NAS) as discussed
further below, the agencies are adopting a HD National Program that
recognizes the different sizes and work requirements of this wide range
of heavy-duty vehicles and their engines. NHTSA's final fuel
consumption standards and EPA's final GHG standards apply to
manufacturers of the following types of heavy-duty vehicles and their
engines; the final provisions for each of these are described in more
detail below in this section:
     Heavy-duty Pickup Trucks and Vans.
     Combination Tractors.
     Vocational Vehicles.
    As in the light-duty 2012-2016 MY vehicle rule, EPA's and NHTSA's
final standards for the heavy-duty sector are largely harmonized with
one another due to the close and direct relationship between improving
the fuel efficiency of these vehicles and reducing their CO2
tailpipe emissions. For all vehicles that consume carbon-based fuels,
the amount of CO2 exhaust emissions is essentially constant
per gallon for a given type of fuel that is consumed. The more
efficient a heavy-duty truck is in completing its work, the lower its
environmental impact will be, because the less fuel consumed to move
cargo a given distance, the less CO2 that truck emits
directly into the air. The technologies available for improving fuel
efficiency, and therefore for reducing both CO2 emissions
and fuel consumption, are one and the same.\15\ Because of this close
technical relationship, NHTSA and EPA have been able to rely on
jointly-developed assumptions, analyses, and analytical conclusions to
support the standards and other provisions that NHTSA and EPA are
adopting under our separate legal authorities.
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    \15\ However, as discussed below, in addition to addressing
CO2, the EPA's final standards also include provisions to
address other GHGs (nitrous oxide, methane, and air conditioning
refrigerant emissions). See Section II.
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    This program is based on standards for direct exhaust emissions
from engines and vehicles. In characterizing the overall emissions
impacts, benefits and costs of the program, analyses of air pollutant
emissions from upstream sources have been conducted. In this action,
the agencies use the term upstream to include emissions from the
production and distribution of fuel. A summary of the analysis of
upstream emissions can be found in Section VI.C of this preamble, and
further details are available in Chapter 5 of the RIA.
    The timelines for the implementation of the final NHTSA and EPA
standards are also closely coordinated. EPA's final GHG emission
standards will begin in model year 2014. In order to provide for the
four full model years of regulatory lead time required by EISA, as
discussed in Section 0 below, NHTSA's final fuel consumption standards
will be voluntary in model years 2014 and 2015, becoming mandatory in
model year 2016, except for diesel engine standards which will be
voluntary in model years 2014, 2015 and 2016, becoming mandatory in
model year 2017. Both agencies are also allowing for early compliance
in model year 2013. A detailed discussion of how the final standards
are consistent with each agency's respective statutory requirements and
authorities is found later in this preamble.
    Allison Transmission stated that sufficient time must be taken
before issuing the final rules in order to ensure that the standards
are supportable. As explained in Sections II and III below, as well as
in the RIA, the agencies believe there is sufficient lead time to meet
all of the standards adopted in today's rules. For those areas for
which the agencies have determined that insufficient time is available
to develop appropriate standards, such as for trailers, the agencies
are not including regulations as part of this initial program.
    NHTSA received several comments related to the timing of the
implementation of its fuel consumption standards. The Engine
Manufacturers Association (EMA), the National Automobile Dealers
Association (NADA), The Volvo Group (Volvo), and Navistar argued that
the timing of NHTSA's standards violated the lead time requirement of
49 U.S.C. 32902(k)(3)(A), which states that standards under the new
medium- and heavy-duty program shall have ``not less than 4 full model
years of regulatory lead-time.'' The commenters seemed to interpret the
voluntary program as the imposition of regulation upon industry. NADA
described NHTSA's standards during the voluntary period as
``mandates.''
    NHTSA has reviewed this issue and believes that the regulatory
schedule is consistent with the lead time requirement of Section
32902(k)(3). To clarify, NHTSA will not be imposing a mandatory
regulatory program until 2016, and none of the voluntary standards will
be ``mandates.'' As described in later sections, the voluntary
standards would only apply to a manufacturer if it makes the voluntary
and affirmative choice to opt-in to the program. \16\ Mandatory NHTSA
standards will first come into effect in 2016, giving industry four
full years of lead time with the NHTSA fuel consumption standards.
---------------------------------------------------------------------------

    \16\ Prior to or at the same time that a manufacturer submits
its first application for a certificate of conformity; See Section V
below.
---------------------------------------------------------------------------

    EMA, NADA, and Navistar also argued that the proposed standards
would violate the stability requirement of 49 U.S.C. 32902(k)(3)(B),
which states that they shall have ``not less than 3 full model years of
regulatory stability.'' EMA stated that since there are HD emission
standards taking effect in 2013, the 2014 implementation date for this
rule would violate the stability requirements. NADA argued that the MY
2014-2017/2018 phase-in period was inadequate to fulfill the stability
requirement.
    Congress has not spoken directly to the meaning of the words
``regulatory stability.'' NHTSA believes that the ``regulatory
stability'' requirement exists to ensure that manufacturers will not be
subject to new standards in repeated rulemakings too rapidly, given
that Congress did not include a minimum duration period for the MD/HD
standards.\17\ NHTSA further believes that standards, which as set
provide for increasing stringency during the period that the standards
are applicable under this rule to be the maximum feasible during the
regulatory period, are within the meaning of the statute. In this
statutory context, NHTSA interprets the phrase ``regulatory stability''
in Section 32902(k)(3)(B) as requiring that the standards remain in
effect for three years before they may be increased by amendment. It
does not prohibit standards which contain pre-determined stringency
increases.
---------------------------------------------------------------------------

    \17\ In contrast, light-duty standards must remain in place for
``at least 1, but not more than 5, model years.'' 23902(b)(3)(B).
---------------------------------------------------------------------------

    As laid out in Section II below, NHTSA's final standards follow
different phase-in schedules based on differences between the
regulatory categories. Consistent with NHTSA's statutory obligation to
implement a program designed to achieve the maximum feasible fuel
efficiency improvement, the standards increase in stringency based upon
increasing fleet penetration rates for the available technologies. The
NPRM proposed phase-in schedules aligned with EPA's,

some of which followed pre-determined stringency increases. The NPRM
also noted that NHTSA was considering alternate standards that would
not change in stringency during the time frame when the regulations are
effective for those standards that increased throughout the mandatory
program. As described in Section II below, the final rule includes the
proposed alternate standards for those standards that follow such a
stringency phase-in path. Therefore, NHTSA believes that the final rule
provides ample stability for each standard.
    Each standard, associated phase-in schedule, and alternative
standard implemented by this final rule was noticed in the NPRM. Those
fuel consumption standards that become mandatory in 2017 will remain in
effect through at least 2019. This further ensures that the fuel
consumption standards in this rule will remain in effect for at least
three years, providing the statutorily-mandated three full years of
regulatory stability, and ensuring that manufacturers will not be
subject to new or amended standards too rapidly. (The greenhouse gas
emission standards remain in effect unless and until amended in all
later model years in any case.) Therefore, NHTSA believes the
commenters' concern about regulatory stability is addressed in the
structure of the rule.
    Neither EPA nor NHTSA is adopting standards at this time for GHG
emissions or fuel consumption, respectively, for heavy-duty commercial
trailers or for vehicles or engines manufactured by small businesses.
The agencies recognize that aerodynamic and tire rolling resistance
improvements to trailers represent a significant opportunity to reduce
fuel consumption and GHGs as evidenced, among other things, by the work
of the EPA SmartWay program. While we are deferring action today on
setting trailer standards, the agencies are committed to moving forward
to create a regulatory program for trailers that would complement the
current vehicle program. See Section IX for more details on the
agencies' decisions regarding trailers, and Sections II and XII for
more details on the agencies' decisions regarding small businesses.
    The agencies have analyzed in detail the projected costs, fuel
savings, and benefits of the final GHG and fuel consumption standards.
Table I-1 shows estimated lifetime discounted program costs (including
technological outlays), fuel savings, and benefits for all heavy-duty
vehicles projected to be sold in model years 2014-2018 over these
vehicles' lives. Section I.D includes additional information about this
analysis.

 Table I-1--Estimated Lifetime Discounted Costs, Fuel Savings, Benefits,
    and Net Benefits for 2014-2018 Model Year Heavy-Duty Vehicles a b
                            [Billions, 2009$]
------------------------------------------------------------------------

------------------------------------------------------------------------
              Lifetime Present Value \c\--3% Discount Rate
------------------------------------------------------------------------
Program Costs..................................................     $8.1
Fuel Savings...................................................       50
Benefits.......................................................      7.3
Net Benefits\d\................................................       49
------------------------------------------------------------------------
                 Annualized Value \e\--3% Discount Rate
------------------------------------------------------------------------
Annualized Costs...............................................      0.4
Fuel Savings...................................................      2.2
Annualized Benefits............................................      0.4
Net Benefits \d\...............................................      2.2
------------------------------------------------------------------------
              Lifetime Present Value \c\--7% Discount Rate
------------------------------------------------------------------------
Program Costs..................................................      8.1
Fuel Savings...................................................       34
Benefits.......................................................      6.7
Net Benefits \d\...............................................       33
------------------------------------------------------------------------
                 Annualized Value \e\--7% Discount Rate
------------------------------------------------------------------------
Annualized Costs...............................................      0.6
Fuel Savings...................................................      2.6
Annualized Benefits............................................      0.5
Net Benefits \d\...............................................      2.5
------------------------------------------------------------------------
Notes:
a The agencies estimated the benefits associated with four different
  values of a one ton CO2 reduction (model average at 2.5% discount
  rate, 3%, and 5%; 95th percentile at 3%), which each increase over
  time. For the purposes of this overview presentation of estimated
  costs and benefits, however, we are showing the benefits associated
  with the marginal value deemed to be central by the interagency
  working group on this topic: the model average at 3% discount rate, in
  2009 dollars. Section VIII.F provides a complete list of values for
  the 4 estimates.
b Note that net present value of reduced GHG emissions is calculated
  differently than other benefits. The same discount rate used to
  discount the value of damages from future emissions (SCC at 5, 3, and
  2.5 percent) is used to calculate net present value of SCC for
  internal consistency. Refer to Section VIII.F for more detail.
c Present value is the total, aggregated amount that a series of
  monetized costs or benefits that occur over time is worth now (in year
  2009 dollar terms), discounting future values to the present.
d Net benefits reflect the fuel savings plus benefits minus costs.
e The annualized value is the constant annual value through a given time
  period (2012 through 2050 in this analysis) whose summed present value
  equals the present value from which it was derived.

B. Building Blocks of the Heavy-Duty National Program

    The standards that are being adopted in this notice represent the
first time that NHTSA and EPA are regulating the heavy-duty sector for
fuel consumption and GHG emissions, respectively. The HD National
Program is rooted in EPA's prior regulatory history, the SmartWay[reg]
Transport Partnership program, and extensive technical and engineering
analyses done at the federal level. This section summarizes some of the
most important of these precursors and foundations for this HD National
Program.
(1) EPA's Traditional Heavy-Duty Regulatory Program
    Since the 1980s, EPA has acted several times to address tailpipe
emissions of criteria pollutants and air toxics from heavy-duty
vehicles and engines. During the last 18 years, these programs have
primarily addressed emissions of particulate matter (PM) and the
primary ozone precursors, hydrocarbons (HC) and oxides of nitrogen
(NOX). These programs have successfully achieved significant
and cost-effective reductions in emissions and associated health and
welfare benefits to the nation. They have been structured in ways that
account for the varying circumstances of the engine and truck
industries. As required by the CAA, the emission standards implemented
by these programs include standards that apply at the time that the
vehicle or engine is sold as well as standards that apply in actual
use. As a result of these programs, new vehicles meeting current
emission standards will emit 98 percent less NOX and 99
percent less PM than new trucks 20 years ago. The resulting emission
reductions provide significant public health and welfare benefits. The
most recent EPA regulations which were fully phased-in in 2010, the
monetized health and welfare benefits alone are projected to be greater
than $70 billion in 2030--benefits far exceeding compliance costs and
not including the unmonetized benefits resulting from reductions in air
toxics and ozone precursors (66 FR 5002, January 18, 2001).
    EPA's overall program goal has always been to achieve emissions
reductions from the complete vehicles that operate on our roads. The
agency has often accomplished this goal for many heavy-duty truck
categories through the regulation of heavy-duty engine emissions. A key
part of this success has been the development over many years of a
well-established, representative, and robust set of engine

test procedures that industry and EPA now routinely use to measure
emissions and determine compliance with emission standards. These test
procedures in turn serve the overall compliance program that EPA
implements to help ensure that emissions reductions are being achieved.
By isolating the engine from the many variables involved when the
engine is installed and operated in a HD vehicle, EPA has been able to
accurately address the contribution of the engine alone to overall
emissions. The agencies discuss below how the final program
incorporates the existing engine-based approach used for criteria
pollutant regulations, as well as new vehicle-based approaches.
(2) NHTSA's Responsibilities To Regulate Heavy-Duty Fuel Efficiency
under EISA
    With the passage of the EISA in December 2007, Congress laid out a
framework developing the first fuel efficiency regulations for HD
vehicles. As codified at 49 U.S.C. 32902(k), EISA requires NHTSA to
develop a regulatory system for the fuel efficiency of commercial
medium-duty and heavy-duty on-highway vehicles and work trucks in three
steps: a study by NAS, a study by NHTSA,\18\ and a rulemaking to
develop the regulations themselves.
---------------------------------------------------------------------------

    \18\ Factors and Considerations for Establishing a Fuel
Efficiency Regulatory Program for Commercial Medium- and Heavy-Duty
Vehicles, October 2010, available at http://www.nhtsa.gov/staticfiles/rulemaking/pdf/cafe/NHTSA_Study_Trucks.pdf.
---------------------------------------------------------------------------

    Specifically, section 102 of EISA, codified at 49 U.S.C.
32902(k)(2), states that not later than two years after completion of
the NHTSA study, DOT (by delegation, NHTSA), in consultation with the
Department of Energy (DOE) and EPA, shall develop a regulation to
implement a ``commercial medium-duty and heavy-duty on-highway vehicle
and work truck fuel efficiency improvement program designed to achieve
the maximum feasible improvement.'' NHTSA interprets the timing
requirements as permitting a regulation to be developed earlier, rather
than as requiring the agency to wait a specified period of time.
    Congress specified that as part of the ``HD fuel efficiency
improvement program designed to achieve the maximum feasible
improvement,'' NHTSA must adopt and implement:
    Appropriate test methods;
    Measurement metrics;
    Fuel economy standards; \19\ and
---------------------------------------------------------------------------

    \19\ In the context of 49 U.S.C. 32902(k), NHTSA interprets
``fuel economy standards'' as referring not specifically to miles
per gallon, as in the light-duty vehicle context, but instead more
broadly to account as accurately as possible for MD/HD fuel
efficiency. While it is a metric that NHTSA considered for setting
MD/HD fuel efficiency standards, the agency recognizes that miles
per gallon may not be an appropriate metric given the work that MD/
HD vehicles are manufactured to do. NHTSA is thus finalizing
alternative metrics as discussed further below.
---------------------------------------------------------------------------

    Compliance and enforcement protocols.
    Congress emphasized that the test methods, measurement metrics,
standards, and compliance and enforcement protocols must all be
appropriate, cost-effective, and technologically feasible for
commercial medium-duty and heavy-duty on-highway vehicles and work
trucks. NHTSA notes that these criteria are different from the ``four
factors'' of 49 U.S.C. 32902(f) \20\ that have long governed NHTSA's
setting of fuel economy standards for passenger cars and light trucks,
although many of the same issues are considered under each of these
provisions.
---------------------------------------------------------------------------

    \20\ 49 U.S.C. 32902(f) states that ``When deciding maximum
feasible average fuel economy under this section, [NHTSA] shall
consider technological feasibility, economic practicability, the
effect of other motor vehicle standards of the Government on fuel
economy, and the need of the United States to conserve energy.''
---------------------------------------------------------------------------

    Congress also stated that NHTSA may set separate standards for
different classes of HD vehicles, which the agency interprets broadly
to allow regulation of HD engines in addition to HD vehicles, and
provided requirements new to 49 U.S.C. 32902 in terms of timing of
regulations, stating that the standards adopted as a result of the
agency's rulemaking shall provide not less than four full model years
of regulatory lead time, and three full model years of regulatory
stability.
(3) National Academy of Sciences Report on Heavy-Duty Technology
    In April 2010 as mandated by Congress in EISA, the National
Research Council (NRC) under NAS issued a report to NHTSA and to
Congress evaluating medium-duty and heavy-duty truck fuel efficiency
improvement opportunities, titled ``Technologies and Approaches to
Reducing the Fuel Consumption of Medium- and Heavy-duty Vehicles.''
\21\ This study covers the same universe of heavy-duty vehicles that is
the focus of this final rulemaking--all highway vehicles that are not
light-duty, MDPVs, or motorcycles. The agencies have carefully
evaluated the research supporting this report and its recommendations
and have incorporated them to the extent practicable in the development
of this rulemaking.
---------------------------------------------------------------------------

    \21\ Committee to Assess Fuel Economy Technologies for Medium-
and Heavy-Duty Vehicles; National Research Council; Transportation
Research Board (2010). ``Technologies and Approaches to Reducing the
Fuel Consumption of Medium- and Heavy-Duty Vehicles,'' (hereafter,
``NAS Report''). Washington, DC, The National Academies Press.
Available electronically from the National Academies Press Website
at http://www.nap.edu/catalog.php?record_id=12845 (last accessed
September 10, 2010).
---------------------------------------------------------------------------

    The NAS report is far reaching in its review of the technologies
that are available and which may become available in the future to
reduce fuel consumption from medium and heavy-duty vehicles. In
presenting the full range of technical opportunities the report
includes technologies which may not be available until 2020 or even
further into the future. As such, the report provides not only a
valuable list of off the shelf technologies from which the agencies
have drawn in developing this near-term 2014-2018 program consistent
with statutory authorities and with the set of principles set forth by
the President, but the report also provides a road map the agencies can
use as we look to develop future regulations for this sector. A review
of the technologies in the NAS report makes clear that there are not
only many technologies readily available today to achieve important
reductions in fuel consumption, like the ones we used in developing the
2014-2018 program, but there are also great opportunities for even
larger reductions in the future through the development of advanced
hybrid drive systems and sophisticated engine technologies such as
Rankine waste heat recovery. The agencies will again make extensive use
of this report when we move forward to develop the next phase of
regulations for medium and heavy-duty vehicles.
    Allison Transmission commented that NHTSA (implicitly, both
agencies) had improperly relied on the NAS report and failed to do
sufficient independent analysis, which Allison claimed did not meet the
statutory obligation to provide an adequate basis for the rule. First,
an agency does not improperly delegate its authority or judgment merely
by using work performed by outside parties as the factual basis for its
decision making. See U.S. Telecom Ass'n v. FCC, 359 F.3d 554, 568 (DC
Cir. 2004); United Steelworkers of Am. v. Marshall, 647 F.2d 1189,
1216-17 (DC Cir. 1980). Here, although EPA and NHTSA carefully
considered the NAS report, the agencies' consideration and use of the
report was not uncritical and the agencies exercised reasonable
independent judgment in developing the proposed and final rules.
Consistent with EISA's direction, NAS submitted a report evaluating MD/
HD fuel economy standards to NHTSA in March of 2010.

Indeed, many commenters argued that the agencies should have adopted
more of the NAS report recommendations. The agencies reviewed the
findings and recommendations of the NAS report when developing the
proposed rules, as was clearly intended by Congress, but also conducted
an independent study, as described throughout the record to the
proposal and summarized in Section X of the NPRM, 75 FR at 74351-56. In
conducting its analysis of the NAS report, the agencies found that
several key recommendations, such as the use of fuel efficiency
metrics, were the best approach to implementing the new program.
However, the agencies rejected other recommendations of the NAS report,
for example, by proposing separate regulation of engines and vehicles
and the regulation of large manufacturers.
(4) The NHTSA and EPA Light-Duty National GHG and Fuel Economy Program
    On May 7, 2010, EPA and NHTSA finalized the first-ever National
Program for light-duty cars and trucks, which set GHG emissions and
fuel economy standards for model years 2012-2016 (See 75 FR 25324). The
agencies have used the light-duty National Program as a model for this
final HD National Program in many respects. This is most apparent in
the case of heavy-duty pickups and vans, which are very similar to the
light-duty trucks addressed in the light-duty National Program both
technologically as well as in terms of how they are manufactured (i.e.,
the same company often makes both the vehicle and the engine). For
these vehicles, there are close parallels to the light-duty program in
how the agencies have developed our respective final standards and
compliance structures, although, as discussed below, the technologies
applied to light-duty trucks are not invariably applicable to heavy-
duty pickups and vans at the same penetration rates in the lead time
afforded in this heavy-duty action. Another difference is that each
agency adopts standards based on attributes other than vehicle
footprint, as discussed below.
    Due to the diversity of the remaining HD vehicles, there are fewer
parallels with the structure of the light-duty program. However, the
agencies have maintained the same collaboration and coordination that
characterized the development of the light-duty program. Most notably,
as with the light-duty program, manufacturers will be able to design
and build vehicles to meet a closely coordinated, harmonized national
program, and avoid unnecessarily duplicative testing and compliance
burdens.
(5) EPA's SmartWay Program
    EPA's voluntary SmartWay Transport Partnership program encourages
shipping and trucking companies to take actions that reduce fuel
consumption and CO2 by working with the shipping community
and the freight sector to identify low carbon strategies and
technologies, and by providing technical information, financial
incentives, and partner recognition to accelerate the adoption of these
strategies. Through the SmartWay program, EPA has worked closely with
truck manufacturers and truck fleets to develop test procedures to
evaluate vehicle and component performance in reducing fuel consumption
and has conducted testing and has established test programs to verify
technologies that can achieve these reductions. Over the last six
years, EPA has developed hands-on experience testing the largest heavy-
duty trucks and evaluating improvements in tire and vehicle aerodynamic
performance. In 2010, according to vehicle manufacturers, approximately
five percent of new combination heavy-duty trucks will meet the
SmartWay performance criteria demonstrating that they represent the
pinnacle of current heavy-duty truck reductions in fuel consumption.
    In developing this HD National Program, the agencies have drawn
from the SmartWay experience, as discussed in detail both in Sections
II and III below (e.g., developing test procedures to evaluate trucks
and truck components) but also in the RIA (estimating performance
levels from the application of the best available technologies
identified in the SmartWay program). These technologies provide part of
the basis for the GHG emission and fuel consumption standards in this
rulemaking for certain types of new heavy-duty Class 7 and 8
combination tractors.
    In addition to identifying technologies, the SmartWay program
includes operational approaches that truck fleet owners as well as
individual drivers and their freight customers can incorporate, that
the NHTSA and EPA believe will complement the final standards. These
include such approaches as improved logistics and driver training, as
discussed in the RIA. This approach is consistent with the one of the
three alternative approaches that the NAS recommended be considered.
The three approaches were raising fuel taxes, relaxing truck size and
weight restrictions, and encouraging incentives to disseminate
information to inform truck drivers about the relationship between
driving behavior and fuel savings. Taxes and truck size and weight
limits are mandated by public law; as such, these options are outside
EPA's and NHTSA's authority to implement. However, complementary
operational measures like driver training, which SmartWay does promote,
can complement the final standards and also provide benefits for the
existing truck fleet, furthering the public policy objectives of
addressing energy security and climate change.
(6) Environment Canada
    The Government of Canada's Department of the Environment
(Environment Canada) assisted EPA's development of this rulemaking by
conducting emissions testing of heavy-duty vehicles at their test
facilities to gather data on a range of possible test cycles, and to
evaluate the impact of certain emissions reduction technologies.
Environment Canada also facilitated the evaluation of heavy-duty
vehicle aerodynamic properties at Canada's National Research Council
wind tunnel, and during coastdown testing.
    We expect the technical collaboration with Environment Canada to
continue as we implement testing and compliance verification procedures
for this rulemaking. We may also begin to develop a knowledge base
enabling improvement upon this regulatory framework for model years
beyond 2018 (for example, improvements to the means of demonstrating
compliance). We also expect to continue our collaboration with
Environment Canada on compliance issues.
    Collaboration with Environment Canada is taking place under the
Canada-U.S. Air Quality Committee.

C. Summary of the Final EPA and NHTSA HD National Program

    When EPA first addressed emissions from heavy-duty trucks in the
1980s, it established standards for engines, based on the amount of
work performed (grams of pollutant per unit of work, expressed as grams
per brake horsepower-hour or g/bhp-hr).\22\ This

approach recognized the fact that engine characteristics are the
dominant determinant of the types of emissions generated, and engine-
based technologies (including exhaust aftertreatment systems) need to
be the focus for addressing those emissions. Vehicle-based
technologies, in contrast, have less influence on overall truck
emissions of the pollutants that EPA has regulated in the past. The
engine testing approach also recognized the relatively small number of
distinct heavy-duty engine designs, as compared to the extremely wide
range of truck designs. EPA concluded at that time that any incremental
gain in conventional emission control that could be achieved through
regulation of the complete vehicle would be small in comparison to the
cost of addressing the many variants of complete trucks that make up
the heavy-duty sector--smaller and larger vocational vehicles for
dozens of purposes, various designs of combination tractors, and many
others.
---------------------------------------------------------------------------

    \22\ The term ``brake power'' refers to engine torque and power
as measured at the interface between the engine's output shaft and
the dynamometer. This contrasts with ``indicated power'', which is a
calculated value based on the pressure dynamics in the combustion
chamber, not including internal losses that occur due to friction
and pumping work. Since the measurement procedure inherently
measures brake torque and power, the final regulations refer simply
to g/hp-hr. This is consistent with EPA's other emission control
programs, which generally include standards in g/kW-hr.
---------------------------------------------------------------------------

    Addressing GHG emissions and fuel consumption from heavy-duty
trucks, however, requires a different approach. Reducing GHG emissions
and fuel consumption requires increasing the inherent efficiency of the
engine as well as making changes to the vehicles to reduce the amount
of work demanded from the engine in order to move the truck down the
road. A focus on the entire vehicle is thus required. For example, in
addition to the basic emissions and fuel consumption levels of the
engine, the aerodynamics of the vehicle can have a major impact on the
amount of work that must be performed to transport freight at common
highway speeds. For this first rulemaking, the agencies proposed a
complementary engine and vehicle approach in order to achieve the
maximum feasible near-term reductions.
    NHTSA received comments on the proposal to create complementary
engine and vehicle standards. Volvo and Daimler argued that EISA
limited NHTSA's authority to the regulation of completed vehicles and
did not give NHTSA authority to regulate engines. 49 U.S.C. 32902(k)(2)
grants NHTSA broad authority to regulate this sector, stating simply
that the Secretary ``shall determine in a rulemaking proceeding how to
implement a commercial medium- and heavy-duty on-highway vehicle and
work truck fuel efficiency improvement program designed to achieve the
maximum feasible improvement,'' considering appropriateness, cost-
effectiveness, and technological feasibility. NHTSA does not believe
that this language precludes the regulation of engines, but rather
explicitly leaves the regulatory approach to the agency's expertise and
discretion. See 75 FR at 74173 n. 36. Considering the factors described
in the NPRM and in Sections III and IV below, NHTSA continues to
believe that the separate regulation of engines and vehicles is both
consistent with the agency's statutory mandate to determine how to
implement a regulatory program designed to achieve the maximum feasible
improvement and facilitates coordination with EPA's efforts to reduce
greenhouse gas emissions. The Clean Air act, of course, mandates
standards for both ``new motor vehicles'' and ``new motor vehicle
engines'', so there is no issue of authority for separate engine
standards under the EPA GHG program. CAA section 202(a)(1).
    As described elsewhere in this preamble, the final standards under
the HD National Program address the complete vehicle, to the extent
practicable and appropriate under the agencies' respective statutory
authorities, through complementary engine and vehicle standards. The
agencies continue to believe that this complementary engine and vehicle
approach is the best way to achieve near term reductions from the
heavy-duty sector. However, we also recognize as did the NAS committee
and a wide range of industry and environmental commenters, that in
order to fully capture the multi-faceted synergistic aspects of engine
and vehicle design a more comprehensive complete vehicle standard may
be appropriate in the future. The agencies are committed to fully
exploring such a possibility and to developing the testing and modeling
tools necessary to enable such a regulatory approach. We intend to work
with all interested stakeholders as we move forward.
(1) Brief Overview of the Heavy-Duty Truck Industry
    The heavy-duty truck sector spans a wide range of vehicles with
often unique form and function. A primary indicator of the extreme
diversity among heavy-duty trucks is the range of load-carrying
capability across the industry. The heavy-duty truck sector is often
subdivided by vehicle weight classifications, as defined by the
vehicle's gross vehicle weight rating (GVWR), which is a measure of the
combined curb (empty) weight and cargo carrying capacity of the
truck.\23\ Table I-2 below outlines the vehicle weight classifications
commonly used for many years for a variety of purposes by businesses
and by several federal agencies, including the Department of
Transportation, the Environmental Protection Agency, the Department of
Commerce, and the Internal Revenue Service.
---------------------------------------------------------------------------

    \23\ GVWR describes the maximum load that can be carried by a
vehicle, including the weight of the vehicle itself. Heavy-duty
vehicles also have a gross combined weight rating (GCWR), which
describes the maximum load that the vehicle can haul, including the
weight of a loaded trailer and the vehicle itself.

                                                        Table I-2--Vehicle Weight Classification
--------------------------------------------------------------------------------------------------------------------------------------------------------
              Class                       2b               3                4                5                6                7                8
--------------------------------------------------------------------------------------------------------------------------------------------------------
GVWR (lb)........................     8,501-10,000    10,001-14,000    14,001-16,000    16,001-19,500    19,501-26,000    26,001-33,000         > 33,001
--------------------------------------------------------------------------------------------------------------------------------------------------------

    In the framework of these vehicle weight classifications, the
heavy-duty truck sector refers to Class 2b through Class 8 vehicles and
the engines that power those vehicles.\24\ Unlike light-duty vehicles,
which are primarily used for transporting passengers for personal
travel, heavy-duty vehicles fill much more diverse operator needs.
Heavy-duty pickup trucks and vans (Classes 2b and 3) are used chiefly
as work truck and vans, and as shuttle vans, as well as for personal
transportation, with an average annual mileage in the range of 15,000
miles. The rest of the heavy-duty sector is used for carrying cargo
and/or performing specialized tasks. ``Vocational'' vehicles, which may
span Classes 2b through 8, vary widely in size, including smaller and
larger van trucks, utility ``bucket'' trucks, tank

trucks, refuse trucks, urban and over-the-road buses, fire trucks,
flat-bed trucks, and dump trucks, among others. The annual mileage of
these trucks is as varied as their uses, but for the most part tends to
fall in between heavy-duty pickups/vans and the large combination
tractors, typically from 15,000 to 150,000 miles per year, although
some travel more and some less. Class 7 and 8 combination tractor-
trailers--some equipped with sleeper cabs and some not--are primarily
used for freight transportation. They are sold as tractors and
sometimes run without a trailer in between loads, but most of the time
they run with one or more trailers that can carry up to 50,000 pounds
or more of payload, consuming significant quantities of fuel and
producing significant amounts of GHG emissions. The combination
tractor-trailers used in combination applications can travel more than
150,000 miles per year.
---------------------------------------------------------------------------

    \24\ Class 2b vehicles designed as passenger vehicles (Medium
Duty Passenger Vehicles, MDPVs) are covered by the light-duty GHG
and fuel economy standards and not addressed in this rulemaking.
---------------------------------------------------------------------------

    EPA and NHTSA have designed our respective standards in careful
consideration of the diversity and complexity of the heavy-duty truck
industry, as discussed next.
(2) Summary of Final EPA GHG Emission Standards and NHTSA Fuel
Consumption Standards
    As described above, NHTSA and EPA recognize the importance of
addressing the entire vehicle in reducing fuel consumption and GHG
emissions. At the same time, the agencies understand that the
complexity of the industry means that we will need to use different
approaches to achieve this goal, depending on the characteristics of
each general type of truck. We are therefore dividing the industry into
three discrete regulatory categories for purposes of setting our
respective standards--combination tractors, heavy-duty pickups and
vans, and vocational vehicles--based on the relative degree of
homogeneity among trucks within each category. For each regulatory
category, the agencies are adopting related but distinct program
approaches reflecting the specific challenges that we see in these
segments. In the following paragraphs, we discuss EPA's final GHG
emission standards and NHTSA's final fuel consumption standards for the
three regulatory categories of heavy-duty vehicles and their engines.
    The agencies are adopting test metrics that express fuel
consumption and GHG emissions relative to the most important measures
of heavy-duty truck utility for each segment, consistent with the
recommendation of the 2010 NAS Report that metrics should reflect and
account for the work performed by various types of HD vehicles. This
approach differs from NHTSA's light-duty program that uses fuel economy
as the basis. The NAS committee discussed the difference between fuel
economy (a measure of how far a vehicle will go on a gallon of fuel)
and fuel consumption (the inverse measure, of how much fuel is consumed
in driving a given distance) as potential metrics for MD/HD
regulations. The committee concluded that fuel economy would not be a
good metric for judging the fuel efficiency of a heavy-duty vehicle,
and stated that NHTSA should instead consider fuel consumption as the
metric for its standards. As a result, for heavy-duty pickup trucks and
vans, EPA and NHTSA are finalizing standards on a per-mile basis (g/
mile for the EPA standards, gallons/100 miles for the NHTSA standards),
as explained in Section 0 below. For heavy-duty trucks, both
combination and vocational, the agencies are adopting standards
expressed in terms of the key measure of freight movement, tons of
payload miles or, more simply, ton-miles. Hence, for EPA the final
standards are in the form of the mass of emissions from carrying a ton
of cargo over a distance of one mile (g/ton-mi). Similarly, the final
NHTSA standards are in terms of gallons of fuel consumed over a set
distance (one thousand miles), or gal/1,000 ton-mile. Finally, for
engines, EPA is adopting standards in the form of grams of emissions
per unit of work (g/bhp-hr), the same metric used for the heavy-duty
highway engine standards for criteria pollutants today. Similarly,
NHTSA is finalizing standards for heavy-duty engines in the form of
gallons of fuel consumption per 100 units of work (gal/100 bhp-hr).
    Section II below discusses the final EPA and NHTSA standards in
greater detail.
(a) Class 7 and 8 Combination Tractors
    Class 7 and 8 combination tractors and their engines contribute the
largest portion of the total GHG emissions and fuel consumption of the
heavy-duty sector, approximately 65 percent, due to their large
payloads, their high annual miles traveled, and their major role in
national freight transport.\25\ These vehicles consist of a cab and
engine (tractor or combination tractor) and a detachable trailer. In
general, reducing GHG emissions and fuel consumption for these vehicles
will involve improvements in aerodynamics and tires and reduction in
idle operation, as well as engine-based efficiency improvements.
---------------------------------------------------------------------------

    \25\ The on-highway Class 7 and 8 combination tractors
constitute the vast majority of this regulatory category, and form
the backbone of this HD National Program. A small fraction of
combination tractors are used in off-road applications and are
regulated differently, as described in Section II.
---------------------------------------------------------------------------

    In general, the heavy-duty combination tractor industry consists of
tractor manufacturers (which manufacture the tractor and purchase and
install the engine) and trailer manufacturers. These manufacturers are
usually not the same entity. We are not aware of any manufacturer that
typically assembles both the finished truck and the trailer and
introduces the combination into commerce for sale to a buyer. The
owners of trucks and trailers are often distinct as well. A typical
truck buyer will purchase only the tractor. The trailers are usually
purchased and owned by fleets and shippers. This occurs in part because
trucking fleets on average maintain 3 trailers per tractor and in some
cases as many as 6 or more trailers per tractor. There are also large
differences in the kinds of manufacturers involved with producing
tractors and trailers. For HD highway tractors and their engines, a
relatively limited number of manufacturers produce the vast majority of
these products. The trailer manufacturing industry is quite different,
and includes a large number of companies, many of which are relatively
small in size and production volume. Setting standards for the products
involved--tractors and trailers--requires recognition of the large
differences between these manufacturing industries, which can then
warrant consideration of different regulatory approaches.
    Based on these industry characteristics, EPA and NHTSA believe that
the most straightforward regulatory approach for combination tractors
and trailers is to establish standards for tractors separately from
trailers. As discussed below in Section IX, the agencies are adopting
standards for the tractors and their engines in this rulemaking, but
did not propose and are not adopting standards for trailers.
    As with the other regulatory categories of heavy-duty vehicles, EPA
and NHTSA have concluded that achieving reductions in GHG emissions and
fuel consumption from combination tractors requires addressing both the
cab and the engine, and EPA and NHTSA each are adopting standards that
reflect this conclusion. The importance of the cab is that its design
determines the amount of power that the engine must produce in moving
the truck down the road. As illustrated in Figure I-1, the loads that
require additional power from the engine include air resistance
(aerodynamics), tire rolling resistance,

and parasitic losses (including accessory loads and friction in the
drivetrain). The importance of the engine design is that it determines
the basic GHG emissions and fuel consumption performance of the engine
for the variety of demands placed on the engine, regardless of the
characteristics of the cab in which it is installed. The agencies
intend for the final standards to result in the application of improved
technologies for lower GHG emissions and fuel consumption for both the
cab and the engine.
---------------------------------------------------------------------------

    \26\ Adapted from Figure 4.1. Class 8 Truck Energy Audit,
Technology Roadmap for the 21st Century Truck Program: A Government-
Industry Research Partnership, 21CT-001, December 2000.
[GRAPHIC] [TIFF OMITTED] TR15SE11.000

    Accordingly, for Class 7 and 8 combination tractors, the agencies
are each finalizing two sets of standards. For vehicle-related
emissions and fuel consumption, tractor manufacturers are required to
meet vehicle-based standards. Compliance with the vehicle standard will
typically be determined based on a customized vehicle simulation model,
called the Greenhouse gas Emissions Model (GEM), which is consistent
with the NAS Report recommendations to require compliance testing for
combination tractors using vehicle simulation rather than chassis
dynamometer testing. This compliance model was developed by EPA
specifically for this final action. It is an accurate and cost-
effective alternative to measuring emissions and fuel consumption while
operating the vehicle on a chassis dynamometer. Instead of using a
chassis dynamometer as an indirect way to evaluate real-world operation
and performance, various characteristics of the vehicle are measured
and these measurements are used as inputs to the model. These
characteristics relate to key technologies appropriate for this
subcategory of truck--including aerodynamic features, weight
reductions, tire rolling resistance, the presence of idle-reducing
technology, and vehicle speed limiters. The model also assumes the use
of a representative typical engine, rather than a vehicle-specific
engine, because engines are regulated separately. Using these inputs,
the model will be used to quantify the overall performance of the
vehicle in terms of CO2 emissions and fuel consumption. The
model's development and design, as well as the sources for inputs, are
discussed in detail in Section II below and in Chapter 4 of the RIA.
(i) Final Standards for Class 7 and 8 Combination Tractors and Their
Engines
    The vehicle standards that EPA and NHTSA are adopting for Class 7
and 8 combination tractor manufacturers are based on several key
attributes related to GHG emissions and fuel consumption that we
believe reasonably represent the many differences in utility and
performance among these vehicles. The final standards differ depending
on GVWR (i.e., whether the truck is Class 7 or Class 8), the height of
the roof of the cab, and whether it is a ``day cab'' or a ``sleeper
cab.'' These later two attributes are important because the height of
the roof, designed to correspond to the height of the trailer,
significantly affects air resistance, and a sleeper cab generally
corresponds to the opportunity for extended duration idle emission and
fuel consumption improvements. We received a number of comments
supporting this approach and no comments that provided a compelling
reason to change our approach in this final action.
    Thus, the agencies have created nine subcategories within the Class
7 and 8 combination tractor category based on the differences in
expected emissions and fuel consumption associated with the key
attributes of GVWR, cab type, and roof height. The agencies are setting
standards beginning in 2014 model year with more stringent standards
following in 2017 model year. Table I-3 presents the agencies'
respective standards for combination tractor manufacturers for the 2017
model year. The standards represent an overall fuel consumption and
CO2 emissions reduction up to 23 percent from the tractors
and the engines installed in them when compared to a baseline 2010
model year tractor and engine without idle shutdown technology. The
standard values shown below differ somewhat from the proposal,
reflecting refinements made to the GEM in response to comments. These
changes did not impact our estimates of the relative effectiveness of
the various control technologies modeled in this final action nor the
overall cost or benefits or cost effectiveness estimated for these
final vehicle standards.
    As proposed, the agencies are exempting certain types of tractors
which operate off-road to be exempt

from the combination tractor vehicle standards (although standards
would still apply to the engines installed in these vehicles). The
criteria for tractors to be considered off-road have been amended
slightly from those proposed, in response to public comment. The
agencies have also recognized, again in response to public comment,
that some combination tractors operate in a manner essentially the same
as vocational vehicles and have created a subcategory of ``vocational
tractors'' as a result. Vocational tractors will be subject to the
standards for vocational vehicles rather than the combination tractor
standards. See Section II.B of this preamble.

  Table I-3--Heavy-Duty Combination Tractor EPA Emissions Standards (G CO2/Ton-Mile) and NHTSA Fuel Consumption
                                         Standards (GAL/1,000 Ton-Mile)
----------------------------------------------------------------------------------------------------------------
                                                                        Day cab                   Sleeper cab
                                                        --------------------------------------------------------
                                                              Class 7            Class 8            Class 8
----------------------------------------------------------------------------------------------------------------
                                     2017 Model Year CO2 Grams per Ton-Mile
----------------------------------------------------------------------------------------------------------------
Low Roof...............................................              104                 80                 66
Mid Roof...............................................              115                 86                 73
High Roof..............................................              120                 89                 72
----------------------------------------------------------------------------------------------------------------
                               2017 Model Year Gallons of Fuel per 1,000 Ton-Mile
----------------------------------------------------------------------------------------------------------------
Low Roof...............................................               10.2                7.8                6.5
Mid Roof...............................................               11.3                8.4                7.2
High Roof..............................................               11.8                8.7                7.1
----------------------------------------------------------------------------------------------------------------

    In addition, the agencies are finalizing separate performance
standards for the engines manufactured for use in these trucks. EPA's
engine-based CO2 standards and NHTSA's engine-based fuel
consumption standards are implemented using EPA's existing test
procedures and regulatory structure for criteria pollutant emissions
from medium- and heavy-duty engines. As at proposal, the final engine
standards vary depending on engine size linked to intended vehicle
service class. Consistent with our proposal, the agencies are
finalizing an interim alternative compression ignition engine standard
for model years 2014-2016. This alternative standard is designed to
provide a glide path for legacy diesel engine products that may not be
able to comply with the final engine standards for model years 2014-16
given the short (approximately 2-year) lead time of this program. We
believe this alternative standard is appropriate for a first-ever
program when the overall baseline performance of the industry is quite
varied and where the short lead time means that not every product can
be brought into compliance by 2014. The alternative standard only
applies through and including model year 2016.
    Separately, EPA is adopting standards for combination tractors that
apply in use. EPA is also finalizing engine-based N2O and
CH4 standards for manufacturers of the engines used in these
combination tractors. EPA is finalizing separate engine-based standards
for N2O and CH4 because the agency believes that
emissions of these GHGs are technologically related solely to the
engine, fuel, and emissions aftertreatment systems, and the agency is
not aware of any influence of vehicle-based technologies on these
emissions. NHTSA is not incorporating standards for N2O and
CH4 because these emissions do not impact fuel consumption
in a significant way. The standards that EPA is finalizing for
N2O and CH4 are less stringent than those we
proposed, reflecting new data provided to EPA in comments on the
proposal showing that the current baseline level of N2O and
CH4 emissions varies more than EPA had expected. EPA expects
that manufacturers of current engine technologies will be able to
comply with the final N2O and CH4 ``cap''
standards with little or no technological improvements; the value of
the standards will be to prevent significant increases in these
emissions as alternative technologies are developed and introduced in
the future. Compliance with the final EPA engine-based CO2
standards and the final NHTSA engine-based fuel consumption standards,
as well as the final EPA N2O and CH4 standards,
will be determined using the appropriate EPA engine test procedure, as
discussed in Sections II.B, II.D, and II.E below.
    As with the other categories of heavy-duty vehicles, EPA and NHTSA
are finalizing respective standards that will apply to Class 7 and 8
tractors at the time of production (as in Table I-3, above). In
addition, EPA is finalizing separate standards that will apply for a
specified period of time in use. All of the standards for these
vehicles, as well as details about the provisions for certification and
implementation of these standards, are discussed in more detail in
Sections II, III, IV, and V below and in the RIA.
(ii) EPA's Final Air Conditioning Leakage Standard for Class 7 and 8
Combination Tractors
    In addition to the final EPA tractor- and engine-based standards
for CO2 and engine-based standards for N2O, and
CH4 emissions, EPA is finalizing a separate standard to
reduce leakage of HFC refrigerant from cabin air conditioning (A/C)
systems from combination tractors, to apply to the tractor
manufacturer. This standard is independent of the CO2
tractor standard, as discussed below in Section II.E.5. Because the
current refrigerant used widely in all these systems has a very high
global warming potential, EPA is concerned about leakage of
refrigerant.\27\
---------------------------------------------------------------------------

    \27\ The global warming potential for HFC-134a refrigerant of
1430 used in this program is consistent with the Intergovernmental
Panel on Climate Change Fourth Assessment Report.
---------------------------------------------------------------------------

    Because the interior volume to be cooled for most tractor cabins is
similar to that of light-duty vehicles, the size and design of current
tractor A/C systems is also very similar. The compliance approach for
Class 7 and 8 tractors is therefore similar to that in the light-duty
rule in that these standards are design-based. Manufacturers will
choose technologies from a menu of leak-reducing technologies
sufficient to comply with the standard, as opposed to using a test to
measure performance.
    However, the final heavy-duty A/C provisions differ in two
important ways from those established in the light-duty rule. First,
the light-duty provisions were established as voluntary ways to

generate credits towards the CO2 g/mi standard, and EPA took
into account the expected use of such credits in determining the
stringency of the CO2 emissions standards. In the HD
National Program, EPA is requiring that manufacturers actually meet a
standard--as opposed to having the opportunity to earn a credit--for A/
C refrigerant leakage. Thus, refrigerant leakage control is not
separately accounted for in the final heavy-duty CO2
standards. We are taking this approach here recognizing that while the
benefits of leakage control are almost identical between light-duty and
heavy-duty vehicles on a per vehicle basis, these benefits on a per
mile basis expressed as a percentage of overall GHG emissions are much
smaller for heavy-duty vehicles due to their much higher CO2
emissions rates and higher annual mileage when compared to light-duty
vehicles. Hence a credit-based approach as done for light-duty vehicles
would provide less motivation for manufacturers to install low leakage
systems even though such systems represent a highly cost effective
means to control GHG emissions. The second difference relates to the
expression of the leakage rate. The light-duty A/C leakage standard is
expressed in terms of grams per year. For EPA's heavy-duty program,
however, because of the wide variety of system designs and
arrangements, a one-size-fits-all gram per year standard would not be
appropriate, so EPA is adopting a standard in terms of annual mass
leakage rate for A/C systems with refrigerant capacities less than or
equal to 733 grams and percent of total refrigerant leakage per year
for A/C systems with refrigerant capacities greater than 733 grams. The
percent of total refrigerant leakage per year requires the total
refrigerant capacity of the A/C system to be taken into account in
determining compliance. EPA believes that this approach--a standard
instead of a credit, and basing the standard on percent or mass of
leakage over time--is more appropriate for heavy-duty tractors than the
light-duty vehicle approach and that it will achieve the desired
reductions in refrigerant leakage. Compliance with the standard will be
determined through a showing by the tractor manufacturer that its A/C
system incorporates a combination of low-leak technologies sufficient
to meet the leakage rate of the applicable standard. The ``menu'' of
technologies is very similar to that established in the light-duty
2012-2016 MY vehicle rule.\28\
---------------------------------------------------------------------------

    \28\ EPA has approved an alternative refrigerant, HFO-1234yf,
which has a very low GWP, for use in light-duty vehicle mobile A/C
systems. The final heavy-duty vehicle A/C leakage standard is
designed to account for use of an alternative, low-GWP refrigerant.
If in the future this refrigerant is approved for heavy-duty
applications and if it becomes widespread as a substitute for HFC-
134a in heavy-duty vehicle mobile A/C systems, EPA may propose to
revise or eliminate the leakage standard.
---------------------------------------------------------------------------

    Finally, the agencies did not propose and are not adopting an A/C
system efficiency standard in this heavy-duty rulemaking, although an
efficiency credit was a part of the light-duty rule. The much larger
emissions of CO2 from a heavy-duty tractor as compared to
those from a light-duty vehicle mean that the relative amount of
CO2 that could be reduced through A/C efficiency
improvements is very small.
    A more detailed discussion of A/C related issues is found in
Section II.E.5 of this preamble.
(b) Heavy-Duty Pickup Trucks and Vans (Class 2b and 3)
    Heavy-duty vehicles with GVWR between 8,501 and 10,000 lb are
classified in the industry as Class 2b motor vehicles per the Federal
Motor Carrier Safety Administration definition. As discussed above,
Class 2b includes MDPVs that are regulated by the agencies under the
light-duty vehicle rule, and the agencies are not adopting additional
requirements for MDPVs in this rulemaking. Heavy-duty vehicles with
GVWR between 10,001 and 14,000 lb are classified as Class 3 motor
vehicles. Class 2b and Class 3 heavy-duty vehicles (referred to in
these rules as ``HD pickups and vans'') together emit about 15 percent
of today's GHG emissions from the heavy-duty vehicle sector.
    About 90 percent of HD pickups and vans are \3/4\-ton and 1-ton
pickup trucks, 12- and 15-passenger vans, and large work vans that are
sold by vehicle manufacturers as complete vehicles, with no secondary
manufacturer making substantial modifications prior to registration and
use. These vehicle manufacturers are companies with major light-duty
markets in the United States, primarily Ford, General Motors, and
Chrysler. Furthermore, the technologies available to reduce fuel
consumption and GHG emissions from this segment are similar to the
technologies used on light-duty pickup trucks, including both engine
efficiency improvements (for gasoline and diesel engines) and vehicle
efficiency improvements.
    For these reasons, EPA believes it is appropriate to adopt GHG
standards for HD pickups and vans based on the whole vehicle (including
the engine), expressed as grams per mile, consistent with the way these
vehicles are regulated by EPA today for criteria pollutants. NHTSA
believes it is appropriate to adopt corresponding gallons per 100 mile
fuel consumption standards that are likewise based on the whole
vehicle. This complete vehicle approach being adopted by both agencies
for HD pickups and vans is consistent with the recommendations of the
NAS Committee in their 2010 Report. EPA and NHTSA also believe that the
structure and many of the detailed provisions of the recently finalized
light-duty GHG and fuel economy program, which also involves vehicle-
based standards, are appropriate for the HD pickup and van GHG and fuel
consumption standards as well, and this is reflected in the standards
each agency is finalizing, as detailed in Section II.C. These
commonalities include a new vehicle fleet average standard for each
manufacturer in each model year and the determination of these fleet
average standards based on production volume-weighted targets for each
model, with the targets varying based on a defined vehicle attribute.
Vehicle testing will be conducted on chassis dynamometers using the
drive cycles from the EPA Federal Test Procedure (Light-duty FTP or
``city'' test) and Highway Fuel Economy Test (HFET or ``highway''
test).\29\
---------------------------------------------------------------------------

    \29\ The Light-duty FTP is a vehicle driving cycle that was
originally developed for certifying light-duty vehicles and
subsequently applied to HD chassis testing for criteria pollutants.
This contrasts with the Heavy-duty FTP, which refers to the
transient engine test cycles used for certifying heavy-duty engines
(with separate cycles specified for diesel and spark-ignition
engines).
---------------------------------------------------------------------------

    For the light-duty GHG and fuel economy standards, the agencies
factored in vehicle size by basing the emissions and fuel economy
targets on vehicle footprint (the wheelbase times the average track
width).\30\ For those standards, passenger cars and light trucks with
larger footprints are assigned higher GHG and lower fuel economy target
levels in acknowledgement of their inherent tendency to consume more
fuel and emit more GHGs per mile. For HD pickups and vans, the agencies
believe that setting standards based on vehicle attributes is
appropriate, but feel that a work-based metric serves as a better
attribute than the footprint attribute utilized in the light-duty
vehicle

rulemaking. Work-based measures such as payload and towing capability
are key among the parameters that characterize differences in the
design of these vehicles, as well as differences in how the vehicles
will be utilized. Buyers consider these utility-based attributes when
purchasing a heavy-duty pickup or van. EPA and NHTSA are therefore
finalizing standards for HD pickups and vans based on a ``work factor''
attribute that combines their payload and towing capabilities, with an
added adjustment for 4-wheel drive vehicles. The agencies received a
number of comments supporting this approach arguing, as the agencies
had, that this approach was an effective way to encourage technology
development and to appropriately reflect the utility of work vehicles
while setting a consistent metric measure of vehicle performance.
---------------------------------------------------------------------------

    \30\ EISA requires CAFE standards for passenger cars and light
trucks to be attribute-based; See 49 U.S.C. 32902(b)(3)(A).
---------------------------------------------------------------------------

    As proposed, the agencies are adopting provisions such that each
manufacturer's fleet average standard will be based on production
volume-weighting of target standards for all vehicles that in turn are
based on each vehicle's work factor. These target standards are taken
from a set of curves (mathematical functions), presented in Section
II.C below and in Sec.  1037.104. EPA is also phasing in the
CO2 standards gradually starting in the 2014 model year, at
15-20-40-60-100 percent of the model year 2018 standards stringency
level in model years 2014-2015-2016-2017-2018, respectively. The phase-
in takes the form of a set of target standard curves, with increasing
stringency in each model year, as detailed in Section II.C. The final
EPA standards for 2018 (including a separate standard to control air
conditioning system leakage) represent an average per-vehicle reduction
in GHGs of 17 percent for diesel vehicles and 12 percent for gasoline
vehicles, compared to a common baseline, as described in Sections II.C
and III.B of this preamble. The rule contains separate standards for
diesel and gasoline heavy duty pickups and vans for reasons described
in Section II.C below. EPA is also finalizing a compliance alternative
whereby manufacturers can phase in different percentages: 15-20-67-67-
67-100 percent of the model year 2019 standards stringency level in
model years 2014-2015-2016-2017-2018-2019, respectively. This
compliance alternative parallels and is equivalent to NHTSA's first
alternative described below.
    NHTSA is allowing manufacturers to select one of two fuel
consumption standard alternatives for model years 2016 and later. The
first alternative defines individual gasoline vehicle and diesel
vehicle fuel consumption target curves that will not change for model
years 2016-2018, and are equivalent to EPA's 67-67-67-100 percent
target curves in model years 2016-2017-2018-2019, respectively. The
target curves for this alternative are presented in Section II.C. The
second alternative uses target curves that are equivalent to the EPA's
40-60-100 percent target curves in model years 2016-2017-2018,
respectively. Stringency for the alternatives has been selected to
allow a manufacturer, through the use of the credit and deficit carry-
forward provisions that the agencies are also finalizing, to rely on
the same product plans to satisfy either of these two alternatives, and
also EPA requirements. If a manufacturer cannot meet an applicable
standard in a given model year, it may make up its shortfall by
overcomplying in a subsequent year, called reconciling a credit
deficit. NHTSA is also allowing manufacturers to voluntarily opt into
the NHTSA HD pickup and van program in model years 2014 or 2015. For
these model years, NHTSA's fuel consumption target curves are
equivalent to EPA's target curves.
    The agencies received a number of comments including from the
Senate authors and supporters of the Ten-in-Ten Fuel Economy Act
suggesting that the standards for heavy-duty pickups and vans should be
made more stringent for gasoline vehicles and that the phase-in timing
of the standards should be accelerated to the 2016 model year (from
2018). We also received comments arguing that the proposed standards
were aggressive and could only be met given the phase-in schedules
proposed by the agencies. In response to these comments, we reviewed
again the technology assessments from the 2010 NAS report, our own
joint light-duty 2012-2016 rulemaking, and information provided by the
commenters relevant to the stringency of these standards. After
reviewing all of the information, we continue to conclude that the
proposed standards and associated phase-in schedules represent
technically stringent but reasonable standards considering the
available lead time and costs to bring the necessary technologies to
market and our own assessments of the efficacy of the technologies when
applied to heavy-duty pickup trucks and vans. Further detail on the
feasibility of the standards and the agencies' choices among
alternative standards is found in Section III.C below.
    The Senate authors and supporters of the Ten-in-Ten Fuel Economy
Act sent a letter to the agencies encouraging the agencies to finalize
a fuel economy labeling requirement for heavy-duty pickups and
vans.\31\ The agencies recognize that consumer information in the form
of a fuel efficiency label can be a valuable tool to help achieve our
goals, and we note that the agencies have just recently finalized a new
fuel economy label for passenger cars and light trucks. See 76 FR at
39478. That rulemaking effort focused solely on modifying an existing
label and was a multi-year process with significant public input. As we
did not propose a consumer label for heavy-duty pickups and vans in
this action and have not appropriately engaged the public in developing
such a label, we are not prepared to finalize a consumer-based label in
this action. However, we do intend to consider this issue as we begin
work on the next phase of regulations, as we recognize that a consumer
label can play an important role in reducing fuel consumption and GHG
emissions.
---------------------------------------------------------------------------

    \31\ See Docket EPA-HQ-OAR-2010-0162.
---------------------------------------------------------------------------

    The form and stringency of the EPA and NHTSA standards curves are
based on a set of vehicle, engine, and transmission technologies
expected to be used to meet the recently established GHG emissions and
fuel economy standards for model year 2012-2016 light-duty vehicles,
with full consideration of how these technologies are likely to perform
in heavy-duty vehicle testing and use. All of these technologies are
already in use or have been announced for upcoming model years in some
light-duty vehicle models, and some are in use in a portion of HD
pickups and vans as well. The technologies include:
     Advanced 8-speed automatic transmissions.
     Aerodynamic improvements.
     Electro-hydraulic power steering.
     Engine friction reductions.
     Improved accessories.
     Low friction lubricants in powertrain components.
     Lower rolling resistance tires.
     Lightweighting.
     Gasoline direct injection.
     Diesel aftertreatment optimization.
     Air conditioning system leakage reduction (for EPA program
only).
    See Section III.B for a detailed analysis of these and other
potential technologies, including their feasibility, costs, and
effectiveness when employed for reducing fuel consumption and
CO2 emissions in HD pickups and vans.
    A relatively small number of HD pickups and vans are sold by
vehicle manufacturers as incomplete vehicles, without the primary load-
carrying

device or container attached. We are generally regulating these
vehicles as Class 2b through 8 vocational vehicles but are also
allowing manufacturers the option to choose to comply with heavy-duty
pickup or van standards, as described in Section I.C.(2)(c). Although,
as with vocational vehicles generally, we have little information on
baseline aerodynamic performance and opportunities for improvement, a
sizeable subset of these incomplete vehicles, often called cab-chassis
vehicles, are sold by the vehicle manufacturers in configurations with
many of the components that affect GHG emissions and fuel consumption
identical to those on complete pickup truck or van counterparts--
including engines, cabs, frames, transmissions, axles, and wheels. We
are including provisions that will allow manufacturers to include these
vehicles, as well as some Class 4 and 5 vehicles, to be regulated under
the chassis-based HD pickup and van program (i.e. subject to the
standards for HD pickups and vans), rather than the vocational vehicle
program. These provisions are described in Section V.B(1)(e).
    In addition to the EPA CO2 emission standards and the
NHTSA fuel consumption standards for HD pickups and vans, EPA is also
finalizing standards for two additional GHGs, N2O and
CH4, as well as standards for air conditioning-related HFC
emissions. These standards are discussed in more detail in Section
II.E. Finally, EPA is finalizing standards that will apply to HD
pickups and vans in use. All of the standards for these HD pickups and
vans, as well as details about the provisions for certification and
implementation of these standards, are discussed in Section II.C.
(c) Class 2b-8 Vocational Vehicles
    Class 2b-8 vocational vehicles consist of a wide variety of vehicle
types. Some of the primary applications for vehicles in this segment
include delivery, refuse, utility, dump, and cement trucks; transit,
shuttle, and school buses; emergency vehicles, motor homes,\32\ tow
trucks, among others. These vehicles and their engines contribute
approximately 20 percent of today's heavy-duty truck sector GHG
emissions.
---------------------------------------------------------------------------

    \32\ NHTSA's final fuel consumption standards will not apply to
recreational vehicles, as discussed in earlier in this preamble
section.
---------------------------------------------------------------------------

    Manufacturing of vehicles in this segment of the industry is
organized in a more complex way than that of the other heavy-duty
categories. Class 2b-8 vocational vehicles are often built as a chassis
with an installed engine and an installed transmission. Both the engine
and transmissions are typically manufactured by other manufacturers and
the chassis manufacturer purchases and installs them. Many of the same
companies that build Class 7 and 8 tractors are also in the Class 2b-8
chassis manufacturing market. The chassis is typically then sent to a
body manufacturer, which completes the vehicle by installing the
appropriate feature--such as dump bed, delivery box, or utility
bucket--onto the chassis. Vehicle body manufacturers tend to be small
businesses that specialize in specific types of bodies or specialized
features.
    EPA and NHTSA proposed that in this vocational vehicle category the
proposed GHG and fuel consumption standards apply to chassis
manufacturers. Chassis manufacturers play a central role in the
manufacturing process. The product they produce--the chassis with
engine and transmission--includes the primary technologies that affect
GHG emissions and fuel consumption. They also constitute a much more
limited group of manufacturers for purposes of developing and
implementing a regulatory program. The agencies believe that a focus on
the body manufacturers would be much less practical, since they
represent a much more diverse set of manufacturers, many of whom are
small businesses. Further, the part of the vehicle that they add
affords very few opportunities to reduce GHG emissions and fuel
consumption (given the limited role that aerodynamics plays in many
types of lower speed and stop-and-go operation typically found with
vocational vehicles.) Therefore, the agencies proposed that the
standards in this vocational vehicle category would apply to the
chassis manufacturers of all heavy-duty vehicles not otherwise covered
by the HD pickup and van standards or Class 7 and 8 combination tractor
standards discussed above. The agencies requested comment on the
proposed focus on chassis manufacturers.
    Volvo and Daimler commented that the EISA does not speak to the
regulation of subsystems, such as engines or incomplete vehicles, and
argued that on the other hand, Section 32902(k)(2) prescribes the
regulation of vehicles. Volvo further stated that precedent for the
regulation of complete vehicles exists in the light-duty fuel economy
rule. As noted above, NHTSA does not believe that EISA mandates a
particular regulatory approach, but rather gives the agency wide
latitude and explicitly leaves that determination to the agency. NHTSA
also notes that its heavy-duty rule creates a new fuel efficiency
program for which the light-duty program does not necessarily serve as
a useful precedent for considerations of its structure. Unlike the
light-duty fuel economy program, MD/HD vehicles are produced in widely
diverse stages. Further, given the MD/HD market structure, where the
complete vehicle manufacturers are numerous, diverse, and often small
businesses, the regulation of complete vehicles would create unique
difficulties for the application of appropriate and feasible
technologies. These same considerations justify EPA's determination,
pursuant to CAA section 202 (a), to regulate only chassis manufacturers
in this first stage of GHG rules for the heavy-duty sector. NHTSA also
notes that this rule does not represent the first time that the agency
has regulated incomplete vehicles. Rather, incomplete vehicles have a
history of regulation under the Federal Motor Vehicle Safety
Standards.\33\ For this first phase of the HD National Program, NHTSA
and EPA believe that given the complexity of the manufacturing process
for vocational vehicles, and given the wide range of entities that
participate in that process, vehicle fuel consumption standards would
be most appropriately applied to chassis manufacturers and not to body
builders.
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    \33\ See 49 U.S.C. 567.5 and 568.4.
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    The agencies continue to believe that regulation of the chassis
manufacturers for this vocational vehicle category will achieve the
maximum feasible improvement in fuel efficiency for purposes of EISA
and appropriate emissions reductions for purposes of the CAA.
Therefore, consistent with our proposal the final standards in this
vocational vehicle category apply to the chassis manufacturers of all
heavy-duty vehicles not otherwise covered by the HD pickup and van
standards or Class 7 and 8 combination tractor standards discussed
above. As discussed above, EPA and NHTSA have concluded that reductions
in GHG emissions and fuel consumption require addressing both the
vehicle and the engine. As discussed above for Class 7 and 8
combination tractors, the agencies are each finalizing two sets of
standards for Class 2b-8 vocational vehicles. For vehicle-related
emissions and fuel consumption, the agencies are adopting standards for
chassis manufacturers: EPA CO2 (g/ton-mile) standards and
NHTSA fuel consumption (gal/1,000 ton-mile) standards). While the
agencies believe that a freight-based metric is broadly appropriate for
vocational vehicles

because the vocational vehicle population is dominated by freight
trucks and maintain that it is appropriate for the first phase of the
program, the agencies may consider other metrics for future phases of a
HD program. Manufacturers will use GEM, the same customized vehicle
simulation model used for Class 7 and 8 tractors, to determine
compliance with the vocational vehicle standards finalized in this
action. The primary manufacturer-generated input into the GEM for this
category of trucks will be a measure of tire rolling resistance, as
discussed further below, because tire improvements are the primary
means of vehicle improvement available at this time for vocational
vehicles. The model also assumes the use of a typical representative,
compliant engine in the simulation, resulting in an overall value for
CO2 emissions and one for fuel consumption. This is done for
the same reason as for combination tractors. As is the case for
combination tractors, the manufacturers of the engines intended for
vocational vehicles will be subject to separate engine-based standards.
(i) Final Standards for Class 2b-8 Vocational Vehicles and Their
Engines
    Based on our analysis and research, the agencies believe that the
primary opportunity for reductions in vocational vehicle GHG emissions
and fuel consumption will be through improved engine technologies and
improved tire rolling resistance. For engines, EPA and NHTSA are
adopting separate standards for the manufacturers of engines used in
Class 2b-8 vocational vehicles (the same approach as for combination
tractors and engines intended for use in those tractors). EPA's final
engine-based CO2 standards and NHTSA's final engine-based
fuel consumption standards vary based on the expected weight class and
usage of the truck into which the engine will be installed. Tire
rolling resistance is closely related to the weight of the vehicle.
Therefore, we are adopting vehicle-based standards for these trucks
which vary according to one key attribute, GVWR. For this initial HD
rulemaking, we are adopting standards based on the same groupings of
truck weight classes used for the engine standards--light heavy-duty,
medium heavy-duty, and heavy heavy-duty. These groupings are
appropriate for the final vehicle-based standards because they parallel
the general divisions among key engine characteristics, as discussed in
Section II.
    The agencies are also finalizing an interim alternative compression
ignition (diesel) engine standard for model years 2014-2016, again
analogous to the alternative standards for compression ignition engines
use in combination tractors. The need for this provision and our
considerations in adopting it are the same for the engines used in
vocational vehicles as for the engines used in combination tractors. As
we proposed, these alternative standards will only be available through
model year 2016. In addition, manufacturers that use the interim
alternative diesel engine standards for model years 2014-2016 under the
EPA program must use equivalent fuel consumption standards under the
NHTSA program.
    For the 2014 to 2016 model years, manufacturers may also choose to
meet alternative engine standards that are phased-in over the model
years to coincide with new EPA On-Board Diagnostic (OBD) requirements
applicable for these same model years. See Sections II.B and II.D
below.
    The agencies received a significant number of comments including
from the Senate authors and supporters of the Ten-in-Ten Fuel Economy
Act arguing that our proposed standards for vocational vehicles did not
reflect all of the technologies identified in the 2010 NAS report. The
commenters encouraged the agencies to expand the program to bring in
additional reductions through the use of new transmission technologies,
vehicle weight reductions and hybrid drivetrains. In general, the
agencies agree with the commenters' central contention that there are
additional technologies to improve the fuel efficiency of vocational
vehicles. As discussed later, we are finalizing provisions to allow new
technologies to be brought into the program through the innovative
technology credit program. More specifically, we are including
provisions to account for and credit the use of hybrid technology as a
technology that can reduce emissions and fuel consumption. Hybrid
technology can currently be a cost-effective technology in certain
specific vocational applications, and the agencies want to recognize
and promote the use of this technology. (See Sections I.E and IV
below.) However, we are not finalizing standards that are premised on
the use of these additional technologies because we have not been able
to develop the test procedures, regulatory mechanisms and baseline
performance data necessary to adopt a more comprehensive approach to
controlling fuel efficiency and GHG emissions from vocational vehicles.
In concept, the agencies would need to know the baseline weight,
aerodynamic performance, and transmission configuration for the wide
range of vocational vehicles produced today. We do not have this
information even for relatively small portions of this market (e.g.
concrete mixers) nor are we well informed regarding the potential
tradeoffs to changes to vehicle utility that might exist for changes to
concrete mixer designs in response to a regulation. Nor did the
commenters provide any such information. Absent this information and
the necessary regulatory tools, we believe the standards we are
finalizing for vocational vehicles represent the most appropriate
standards for this segment during the model years of the first phase of
the program. We intend to address fuel consumption and GHG emissions
from these vehicles in a more comprehensive manner through future
regulation and look forward to working with all stakeholders on this
important segment in the future.
    The agencies are setting standards beginning in the 2014 model year
and establishing more stringent standards in the 2017 model year. Table
I-4 presents EPA's final CO2 standards and NHTSA's final
fuel consumption standards for chassis manufacturers of Class 2b
through Class 8 vocational vehicles for the 2017 model year. The 2017
model year standards represent a 6 to 9 percent reduction in
CO2 emissions and fuel consumption over a 2010 model year
vehicle.

   Table I-4--Final 2017 Class 2b-8 Vocational Vehicle EPA CO2 Standards and NHTSA Fuel Consumption Standards
----------------------------------------------------------------------------------------------------------------
                                                          Light heavy-duty  Medium heavy-duty   Heavy heavy-duty
                                                             Class 2b-5         Class 6-7           Class 8
----------------------------------------------------------------------------------------------------------------
                           EPA CO2 (gram/ton-mile) Standard Effective 2017 Model Year
----------------------------------------------------------------------------------------------------------------
CO2 Emissions..........................................              373                225                222
----------------------------------------------------------------------------------------------------------------

              NHTSA Fuel Consumption (gallon per 1,000 ton-mile) Standard Effective 2017 Model Year
----------------------------------------------------------------------------------------------------------------
Fuel Consumption.......................................               36.7               22.1               21.8
----------------------------------------------------------------------------------------------------------------

     As mentioned above for Class 7 and 8 combination tractors, EPA
believes that N2O and CH4 emissions are
technologically related solely to the engine, fuel, and emissions
aftertreatment systems, and the agency is not aware of any influence of
vehicle-based technologies on these emissions. Therefore, for Class 2b-
8 vocational vehicles, EPA's final N2O and CH4
standards cover manufacturers of the engines to be used in vocational
vehicles. EPA did not propose, nor are we adopting separate vehicle-
based standards for these GHGs. As for the engines used in Class 7 and
8 tractors, we are finalizing a somewhat higher N2O and
CH4 emission standards reflecting new data submitted to the
agencies during the public comment period. EPA expects that
manufacturers of current engine technologies will be able to comply
with the final ``cap'' standards with little or no technological
improvements; the value of the standards is that they will prevent
significant increases in these emissions as alternative technologies
are developed and introduced in the future. Compliance with the final
EPA engine-based CO2 standards and the final NHTSA fuel
consumption standards, as well as the final EPA N2O and
CH4 standards, will be determined using the appropriate EPA
engine test procedure, as discussed in Section II below.
    As with the other regulatory categories of heavy-duty vehicles, EPA
and NHTSA are adopting standards that apply to Class 2b-8 vocational
vehicles at the time of production, and EPA is adopting standards for a
specified period of time in use. All of the standards for these trucks,
as well as details about the final provisions for certification and
implementation of these standards, are discussed in more detail later
in this notice and in the RIA.
    EPA did not propose, nor is it adopting A/C refrigerant leakage
standards for Class 2b-8 vocational vehicles, primarily because of the
number of entities involved in their manufacture and thus the potential
for different entities besides the chassis manufacturer to be involved
in the A/C system production and installation.
(d) What manufacturers are not covered by the final standards?
    The NPRM proposed to defer temporarily greenhouse gas emissions and
fuel consumption standards for any manufacturers of heavy-duty engines,
manufacturers of combination tractors, and chassis manufacturers for
vocational vehicles that meet the ``small business'' size criteria set
by the Small Business Administration (SBA). 13 CFR 121.201 defines a
small business by the maximum number of employees; for example, this is
currently 1,000 for heavy-duty vehicle manufacturing and 750 for engine
manufacturing.\34\ The agencies stated that they would instead consider
appropriate GHG and fuel consumption standards for these entities as
part of a future regulatory action. This includes both U.S.-based and
foreign small-volume heavy-duty manufacturers. To ensure that the
agencies are aware of which companies would be exempt, the agencies
proposed to require that such entities submit a declaration describing
how it qualifies as a small entity under the provisions of 13 CFR
121.201 to EPA and NHTSA as prescribed in Section V below.
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    \34\ See Sec.  1036.150 and Sec.  1037.150
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    EPA and NHTSA were not aware of any manufacturers of HD pickups and
vans that meet these criteria. For each of the other categories and for
engines, the agencies identified a small number of manufacturers that
would appear to qualify as small businesses under the SBA size
criterion, which were estimated to comprise a negligible percentage of
the U.S. market.\35\ Therefore, the agencies believed that deferring