[Federal Register: November 4, 2010 (Volume 75, Number 213)]
[Notices]
[Page 68093-68150]
[DOCID:fr04no10-114]

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Part III

Environmental Protection Agency

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Partial Grant and Partial Denial of Clean Air Act Waiver Application
Submitted by Growth Energy To Increase the Allowable Ethanol Content of
Gasoline to 15 Percent; Decision of the Administrator; Notice

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ENVIRONMENTAL PROTECTION AGENCY

[EPA-HQ-OAR-2009-0211; FRL-9215-5]

Partial Grant and Partial Denial of Clean Air Act Waiver
Application Submitted by Growth Energy To Increase the Allowable
Ethanol Content of Gasoline to 15 Percent; Decision of the
Administrator

AGENCY: Environmental Protection Agency.

ACTION: Notice of partial waiver decision.

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SUMMARY: The Environmental Protection Agency (EPA) is partially
granting Growth Energy's waiver request application submitted under
section 211(f)(4) of the Clean Air Act. This partial waiver allows fuel
and fuel additive manufacturers to introduce into commerce gasoline
that contains greater than 10 volume percent ethanol and no more than
15 volume percent ethanol (E15) for use in certain motor vehicles if
certain conditions are fulfilled. We are partially approving the waiver
for and allowing the introduction into commerce of E15 for use only in
model year 2007 and newer light-duty motor vehicles, which includes
passenger cars, light-duty trucks and medium-duty passenger vehicles.
We are denying the waiver for introduction of E15 for use in model year
2000 and older light-duty motor vehicles, as well as all heavy-duty
gasoline engines and vehicles, highway and off-highway motorcycles, and
nonroad engines, vehicles, and equipment. The Agency is deferring a
decision on the applicability of a waiver to model year 2001 through
2006 light-duty motor vehicles until additional test data, currently
under development, is available.

ADDRESSES: EPA has established a docket for this action under Docket ID
No. EPA-HQ-OAR-2009-0211. All documents and public comments in the
docket are listed on the http://www.regulations.gov Web site. Publicly
available docket materials are available either electronically through
http://www.regulations.gov or in hard copy at the Air and Radiation
Docket in the EPA Headquarters Library, EPA West Building, Room 3334,
1301 Constitution Ave., NW., Washington, DC. The Public Reading Room is
open from 8:30 a.m. to 4:30 p.m., Monday through Friday, excluding
holidays. The telephone number for the Reading Room is<PHONE_NUMBER>.
The Air and Radiation Docket and Information Center's Web site is
http://www.epa.gov/oar/docket.html. The electronic mail (e-mail)
address for the Air and Radiation Docket is<EMAIL_ADDRESS>
the telephone number is<PHONE_NUMBER> and the fax number is (202) 566-
9744.

FOR FURTHER INFORMATION CONTACT: Robert Anderson, Office of
Transportation and Air Quality, Mailcode: 6405J, Environmental
Protection Agency, 1200 Pennsylvania Ave., NW., Washington, DC 20460;
telephone number:<PHONE_NUMBER>; fax number:<PHONE_NUMBER>; e-mail
address<EMAIL_ADDRESS>
SUPPLEMENTARY INFORMATION:

Table of Contents

I. Executive Summary
     MY2007 and Newer Light-Duty Motor Vehicles
     Durability/Long-Term Exhaust Emissions
     Immediate Exhaust Emissions
     Evaporative Emissions
     Materials Compatibility
     Drivability and Operability
     MY2000 and Older Light-Duty Motor Vehicles
     MY2001-2006 Light-Duty Motor Vehicles
     Nonroad Engines, Vehicles, and Equipment (Nonroad
Products)
     Heavy-Duty Gasoline Engines and Vehicles
     Highway and Off-Highway Motorcycles
     Conditions on Today's Partial Waiver
     Misfueling Mitigation Measures Notice of Proposed
Rulemaking (NPRM)
II. Introduction
    A. Statutory Background
    B. Growth Energy Application and Review Process
    C. Today's Notice of Proposed Rulemaking (NPRM) on Misfueling
Mitigation Measures
III. Method of Review
IV. Waiver Submissions and Analysis of Light-Duty Motor Vehicle
Issues
    A. MY2007 and Newer Motor Vehicles
    1. Exhaust Emissions--Long-Term Durability
    a. Growth Energy's Submission
    b. Public Comment Summary
    c. EPA Response Regarding the Need for Long-Term Exhaust
Emissions (Durability) Testing
    i. General Long-term Exhaust Emissions (Durability) Concerns
    ii. Response to Growth Energy's First Argument
    iii. Conclusion to Growth Energy's Second Argument
    d. Durability Studies and EPA Analysis
    i. DOE Catalyst Study Overview
    ii. Vehicle Selection and Matching
    iii. Fuels and Blending
    iv. Emissions Test Protocol
    v. Mileage Accumulation
    vi. Powertrain Component Inspection
    vii. Summary and Conclusions of the Final Results of the DOE
Catalyst Study
    2. Exhaust Emissions--Immediate Effects for MY2007 and Newer
Light-Duty Motor Vehicles
    a. Growth Energy's Submission
    b. Public Comment Summary
    c. EPA Analysis
    d. Conclusion
    3. Evaporative Emissions on MY2007 and Newer Light-Duty Motor
Vehicles
    a. Introduction
    b. Growth Energy's Submission
    c. Public Comment Summary
    d. EPA Analysis
    e. Conclusion
    4. Materials Compatibility for MY2007 and Newer Light-Duty Motor
Vehicles
    a. Introduction
    b. Growth Energy's Submission
    c. Public Comment Summary
    d. EPA Analysis
    e. Conclusions
    5. Driveability and Operability for MY2007 and Newer Light-Duty
Motor Vehicles
    a. Introduction
    b. Growth Energy's Submission
    c. Public Comment Summary
    d. EPA Analysis
    e. Conclusions
    6. Overall Immediate and Long-Term Emissions Conclusions
    B. MY2001-2006 Light-Duty Motor Vehicles
    C. MY2000 and Older Light-Duty Motor Vehicles
    1. Growth Energy's Submission
    2. Public Comment Summary
    3. EPA Analysis and Conclusion
    a. Scope of MY2000 and Older Motor Vehicles Data to Support a
Waiver Decision
    b. Exhaust Emissions--Long-Term Durability
    i. General Exhaust Emissions Durability Concerns
    ii. Immediate Exhaust Emission Impacts
    c. Evaporative Emissions
    d. Materials Compatibility
V. Nonroad Engines, Vehicles and Equipment (Nonroad Products)
    A. Introduction
    B. Growth Energy Submission
    C. Public Comment Summary
    D. EPA Analysis
    1. Scope of Nonroad Data to Support a Waiver Decision
    2. Long-Term Exhaust Emissions (Durability)
    3. Immediate Exhaust Emission Effects
    4. Evaporative Emissions
    5. Materials Compatibility
    6. Driveability and Operability
    E. Conclusion
VI. Heavy-Duty Gasoline Engines and Vehicles
VII. Motorcycles
VIII. E12 Midlevel Ethanol Blends
    A. First Argument: E12 Is Already Used in the Marketplace With
No Reported Problems
    1. ADM Argument
    2. Comments
    3. EPA Analysis
    B. Second Argument: EPA Effectively Allows Ethanol Blends
Greater Than E10
    1. ADM Argument
    2. EPA Analysis
    C. Third Argument: EPA's Models Allow Greater Than 10 vol%
Ethanol
    1. ADM Argument
    2. API and Alliance Comments

    3. EPA Analysis
    D. Fourth Argument: ADM's Argument for an E12 Waiver
    1. ADM Argument
    2. API, AllSAFE and Alliance Comments
    3. EPA Response
    E. Fifth Argument: E12 Is ``Substantially Similar'' to
Certification Fuel
    1. ADM Argument
    2. API, AllSAFE and Alliance Comments
    3. EPA Response
    F. EPA Conclusion
IX. Legal Issues Arising in This Partial Waiver Decision
    A. Partial Waiver and Conditions of E15 Use
    B. Notice and Comment Procedures
    C. ``Useful Life'' Language in Section 211(f)(4)
X. Waiver Conditions
    A. Fuel Quality Conditions
    B. Misfueling Mitigation Conditions and Strategies
    1. Fuel Pump Dispenser Labeling
    2. Fuel Pump Labeling and Fuel Sample Survey
    3. Proper Documentation of Ethanol Content on Product Transfer
Documents
    4. Public Outreach
XI. Reid Vapor Pressure
XII. Partial Waiver Decision and Conditions

I. Executive Summary

    In March 2009, Growth Energy and 54 ethanol manufacturers
petitioned the Environmental Protection Agency (``EPA'' or ``The
Agency'') to allow the introduction into commerce of up to 15 volume
percent (vol%) ethanol in gasoline. In April 2009, EPA sought public
comment on the Growth Energy petition and subsequently received about
78,000 comments. Prior to today's action, ethanol was limited to 10
vol% in motor vehicle gasoline (E10).
    In today's action, EPA is partially granting Growth Energy's waiver
request based on our careful analysis of the available information,
including test data and public comments. This partial grant waives the
prohibition on fuel and fuel additive manufacturers on the introduction
into commerce of gasoline containing greater than 10 vol% ethanol and
no more than 15 vol% ethanol (E15) for use in certain motor vehicles.
More specifically, today's action has two components. First, we are
approving the waiver for and allowing the introduction into commerce of
E15 for use in Model Year (MY) 2007 and newer light-duty motor
vehicles, which includes passenger cars, light-duty trucks, and medium-
duty passenger vehicles.\1\ Second, we are denying the waiver for
introduction into commerce of E15 for use in MY2000 and older light-
duty motor vehicles, as well as heavy-duty gasoline highway engines and
vehicles (e.g., delivery trucks). Highway and off-highway motorcycles,
and nonroad engines, vehicles, and equipment (nonroad products; e.g.,
boats, snowmobiles, and lawnmowers) typically use the same gasoline as
highway motor vehicles; this decision is also a denial of a waiver for
introducing motor vehicle gasoline into commerce containing more than
10 vol% ethanol for use in all of those products. The Agency is
deferring a decision on the applicability of a waiver with respect to
MY2001-2006 light-duty motor vehicles to await additional test data.
The Department of Energy (DOE) has stated that it will complete testing
on these vehicles in November, after which EPA will take appropriate
action.
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    \1\ For purposes of today's decision, ``MY2007 and newer light-
duty motor vehicles'' include MY2007 and newer light-duty motor
vehicles (LDV), light-duty trucks (LDT), and medium-duty passenger
vehicles (MDPV).
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    To help ensure that E15 is only used in MY2007 and newer light-duty
motor vehicles, EPA has developed a proposed rule (described below)
with the express purpose of mitigating the potential for misfueling of
E15 into vehicles and engines not approved for its use. EPA believes
the proposed safeguards against misfueling would provide the most
practical way to mitigate the potential for misfueling with E15.
Moreover, the proposed rule, when adopted, would satisfy the misfueling
mitigation conditions of today's partial waiver described below and
would promote the successful introduction of E15 into commerce.
However, if parties covered by this waiver (fuel and fuel additive
manufacturers, which include renewable fuel producers and importers,
petroleum refiners and importers, and ethanol blenders) desire to
introduce E15 into commerce prior to a final rule being issued, they
may do so provided they submit and EPA approves a plan that
demonstrates that the misfueling mitigation conditions will be
satisfied. In addition to the misfueling mitigation conditions, E15
must also meet certain fuel quality specifications before it may be
introduced into commerce.
    To receive a waiver, as prescribed by the Clean Air Act, a fuel or
fuel additive manufacturer must demonstrate that a new fuel or fuel
additive will not cause or contribute to the failure of an engine or
vehicle to achieve compliance with the emission standards to which it
has been certified over its useful life. Reflecting that EPA's emission
standards have continued to evolve and become more stringent over time,
the in-use fleet is composed of vehicles and engines spanning not only
different technologies, but also different emissions standards. Since
ethanol affects different aspects of emissions, a wide range of data
and information covering a wide range of highway and nonroad vehicles,
engines, and equipment would be necessary for approval of an E15 waiver
that would allow E15 to be introduced into commerce for use in all
motor vehicles and all other engines and vehicles using motor vehicle
gasoline (``full waiver''). Growth Energy did not provide the necessary
information to support a full waiver in several key areas, especially
long-term durability emissions data necessary to ensure that all motor
vehicles, heavy-duty gasoline highway engines and vehicles, highway and
off-highway motorcycles and nonroad products would continue to comply
with their emission standards over their full useful life. In 2008, DOE
began emissions durability testing on 19 Tier 2 motor vehicle models
that would provide this data for MY2007 and newer light-duty motor
vehicles (``DOE Catalyst Study'').\2\ Consequently, the Agency delayed
a decision until the DOE test program was completed for these motor
vehicles in September 2010.
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    \2\ DOE embarked on the study, in consultation with EPA, auto
manufacturers, fuel providers and others, after enactment of the
Energy Independence and Security Act of 2007, which significantly
expanded the Federal Renewable Fuel Standard Program for increasing
the use of renewable fuels in transportation fuel in order to reduce
imported petroleum and emissions of greenhouse gases.
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    EPA reached its decision on the waiver request based on the results
of the DOE Catalyst Study and other information and test data submitted
by Growth Energy and in public comments. EPA also applied engineering
judgment, based on the data in reaching its decision. Specifically,
consistent with past waiver decisions, the Agency evaluated Growth
Energy's waiver request and made its decision based on four factors:
(1) Exhaust emissions impacts--long-term (known as durability) and
immediate; (2) evaporative system impacts--both immediate and long-
term; (3) the impact of materials compatibility on emissions; and, (4)
the impact of drivability and operability on emissions. The Agency's
conclusions are summarized below and additional information on each
subject is provided later in this decision document.

MY2007 and Newer Light-Duty Motor Vehicles

    For MY2007 and newer light-duty motor vehicles, the DOE Catalyst
Study and other information before EPA adequately demonstrates that the
impact of E15 on overall emissions, including both immediate \3\ and
durability related

emissions, will not cause or contribute to violations of the emissions
standards for these motor vehicles. Likewise, the data and information
adequately show that E15 will not lead to violations of the evaporative
emissions standards, so long as the fuel does not exceed a Reid Vapor
Pressure (RVP) of 9.0 psi in the summertime control season.\4\ The
information on materials compatibility and drivability also supports
this conclusion.
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    \3\ In past waiver decisions, we have referred to ``immediate''
emissions as ``instantaneous'' emissions. ``Immediate'' and
``instantaneous'' are synonymous in this context.
    \4\ EPA regulates the vapor pressure of gasoline sold at retail
stations during the summer ozone season (June 1 to September 15) to
reduce evaporative emissions from gasoline that contribute to
ground-level ozone and diminish the effects of ozone-related health
problems. Gasoline needs a higher vapor pressure in the wintertime
for cold start purposes.
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Durability/Long-Term Exhaust Emissions
    The DOE Catalyst Study involved 19 high sales volume car and light-
duty truck models (MY2005-2009 motor vehicles produced by the top U.S.
sales-based automobile manufacturers) that are all designed for and
subject to the Tier 2 motor vehicle emission standards. The purpose of
the program was to evaluate the long term effects of E0 (gasoline that
contains no ethanol and is the certification test fuel for emissions
testing), E10, E15, and E20 (a gasoline-ethanol blend containing 20
vol% ethanol) on the durability of the exhaust emissions control
system, especially the catalytic converter (catalyst), for Tier 2 motor
vehicles. Analysis of the motor vehicles' emissions results at full
useful life (120,000 miles) and emissions deterioration rates showed no
significant difference between the E0 and E15 fueled groups. Three
motor vehicles aged on EO fuel had failing emissions levels and one
additional motor vehicle failed one of several replicate tests. One
E15-aged motor vehicle had failing emissions.\5\ However, none of the
emissions failures appeared to be related to the fuel used. There were
no emissions component or material failures during aging that were
related to fueling. In addition, a review of the emission deterioration
rates over the course of the test program revealed no statistically
significant difference in emissions deterioration with E15 in
comparison to E0. Using standard statistical tools, the test results
support the conclusion that E15 does not cause or contribute to the
failure of MY2007 and newer light-duty motor vehicles in achieving
their emissions standards over their useful lives. These results
confirm EPA's engineering assessment that the changes manufacturers
made to their motor vehicles (calibration, hardware, etc.) to comply
with the Agency's stringent Tier 2 emission standards (which began to
phase in with MY2004) have resulted in the capability of Tier 2 motor
vehicles to accommodate the additional enleanment caused by E15 and be
compatible with ethanol concentrations up to E15.\6\. EPA's
certification data show that all gasoline-fueled cars and light-duty
trucks were fully phased in to the Tier 2 standards by MY2007 even
though the program did not require the phase-in to be complete until
MY2009. Consequently, EPA believes it appropriate to apply these test
results to all MY2007 and newer light-duty motor vehicles.
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    \5\ It should be noted that the Dodge Caliber vehicle aged on
E15 failed Tier 2 Bin 5 FUL standards on E0. However, this vehicle
met Tier 2 Bin 5 FUL standards when tested on E15. The Agency could
not determine the cause.
    \6\ See 65 FR 6698 (February 10, 2000).
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Immediate Exhaust Emissions
    Scientific information supports a conclusion that motor vehicles
experience an immediate emissions impact independent of motor vehicle
age (and therefore emission control technology) when operating on
gasoline-ethanol blends. Nitrogen oxide (NOX) emissions
generally increase while volatile organic compound (VOC) and carbon
monoxide (CO) emissions decrease. The available data supports a
conclusion that the immediate emissions impacts of E15 on Tier 2 motor
vehicles are likely to have the same pattern as the immediate emissions
impacts of E10 on older motor vehicles (i.e., NOX emissions
increase while VOC and CO emissions decrease). Although the magnitude
of the immediate impact is expected to be slightly greater with E15,
Tier 2 motor vehicles generally have a significant compliance margin at
the time of certification and later on in-use (when they are in
customer service) that should allow them to meet their emission
standards even if they experience the predicted immediate
NOX increases from E15 when compared to E0. The results of
the DOE Catalyst Study reflect both the immediate emissions effects as
well as any durability effects as described above, and the Tier 2 motor
vehicles continued to comply with their emissions standards at their
full useful life. As noted above, none of the emissions failures
appeared to be related to the fuel used. Based on this immediate
exhaust emissions information, coupled with the durability test data
and conclusions, E15 is not expected to cause Tier 2 motor vehicles to
exceed their exhaust standards over their useful lives when operated on
E15.
Evaporative Emissions
    Both diurnal and running loss evaporative emissions increase as
fuel volatility increases. Diurnal evaporative emissions occur when
motor vehicles are not operating and experience the change in
temperature during the day, such as while parked. Running loss
evaporative emissions occur while motor vehicles are being operated.
Reid Vapor Pressure (RVP) is the common measure of the volatility of
gasoline. E15 that meets an RVP limit of 9.0 pounds per square inch
(psi) during the summer (which is equal to the RVP of E0) should not
produce higher diurnal or running loss evaporative emissions than E0.
We expect MY2007 and newer vehicles to meet evaporative emissions
standard on 9.0 psi E15. There are concerns with E15 having an RVP
greater than 9.0 psi. When ethanol is blended at 15 vol%, a 10.0 psi
RVP fuel compared to 9.0 psi RVP fuel will have substantially higher
evaporative emissions levels that must be captured by the emissions
control system (a carbon filled canister and related system elements).
This increase in evaporative emissions is beyond what manufacturers
have been required to control, based on the motor vehicle certification
testing for the emissions standards. Test results highlight the concern
that fuel with an RVP greater than 9.0 psi during the summer will lead
to motor vehicles exceeding their evaporative emission standards in-
use. Additionally, as explained in the misfueling mitigation measures
proposed rule, EPA interprets the 1.0 psi waiver in CAA section 211(h)
as being limited to gasoline-ethanol blends that contain 10 vol%
ethanol. Therefore, given the significant potential for increased
evaporative emissions at higher gasoline volatility levels, and the
lack of data to resolve how this would impact compliance with the
emissions standards, today's waiver is limited to E15 with a summertime
RVP no higher than 9.0 psi.
    Other potential issues for evaporative emissions of motor vehicles
operated on E15 are increased permeation and long-term (durability)
impacts.\7\ Available test data indicate that for Tier 2 motor vehicles
any increase in evaporative emissions as a result of permeation is
limited and within the evaporative

compliance margins for these motor vehicles. This is consistent with
the demonstration of evaporative emissions system durability after
aging on E10 that was required beginning with the Tier 2 motor vehicle
standards, for the purpose of limiting permeation. With respect to
durability of the evaporative emissions control systems, data from
several aspects of the DOE Catalyst Study point to the expected
durability of the evaporative emissions control system of Tier 2 motor
vehicles on E15. First, there appears to be no evidence of an increase
in evaporative emissions system onboard diagnostic system codes being
triggered by E15 compared to E0. Second, teardown results of the 12
motor vehicles tested (six models with E0 and six models with E15)
found no abnormalities for E15 motor vehicles compared to E0 motor
vehicles.\8\ Finally, evaporative testing on four of the Tier 2 motor
vehicles over the course of the test program found no increased
deterioration in evaporative emissions with E15 in comparison to E0.\9\
Therefore, after taking into account all of these sources of
evaporative emissions data, the evidence supports a conclusion that as
long as E15 meets a summertime control season gasoline volatility level
of no higher than 9.0 psi, E15 is not expected to cause or contribute
to exceedances of the evaporative emission standards over the full
useful life of Tier 2 motor vehicles.
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    \7\ Permeation refers to the migration of fuel molecules through
the walls of elastomers used for fuel system components.
    \8\ Southwest Research Institute Project 08-58845 Status Report,
``Powertrain Component Inspection from Mid-Level Blends Vehicle
Aging Study,'' September 6, 2010. See EPA-HQ-OAR-2009-0211-14016.
    \9\ Environmental Testing Corporation NREL Subcontract JGC-9-
99141-01 Presentation, ``Vehicle Aging and Comparative Emissions
testing Using E0 and E15 Fuels: Evaporative Emissions Results,''
August 31, 2010. See EPA-HQ-OAR-2009-0211-14015.
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Materials Compatibility
    Materials compatibility is a key factor in considering a fuel or
fuel additive waiver insofar as poor materials compatibility can lead
to serious exhaust and evaporative emission compliance problems not
only immediately upon use of the new fuel or fuel additive, but
especially over the full useful life of vehicles and engines. As part
of its E15 waiver application, Growth Energy submitted a series of
studies completed by the State of Minnesota and the Renewable Fuels
Association (RFA) that investigated materials compatibility of motor
vehicle engines and engine components using three test fuels: E0, E10,
and E20. The materials studied included what were considered to be many
of the common metals, elastomers, and plastics used in motor vehicle
fuel systems. Growth Energy concluded that E15 would not be problematic
for current automotive or fuel dispensing equipment. While
directionally illustrative, the materials compatibility information
submitted by Growth Energy does not encompass all materials used in
motor vehicle fuel systems, and the test procedures used are not
representative of the dynamic real-world conditions under which the
materials must perform. The information is therefore insufficient by
itself to adequately assess the potential material compatibility of
E15. However, the information generated through the DOE Catalyst Study
demonstrates that MY2007 and newer light-duty motor vehicles will not
experience materials compatibility issues that lead to exhaust or
evaporative emission exceedances. The DOE Catalyst Study supports the
Agency's engineering assessment that newer motor vehicles such as those
subject to EPA's Tier 2 standards, were designed to encounter more
regular ethanol exposure compared to earlier model year motor vehicles.
Other regulatory requirements also placed an emphasis on real world
motor vehicle testing, which in turn prompted manufacturers to consider
different available fuels when developing and testing their emissions
systems. Additionally, beginning with Tier 2, the evaporative
durability demonstration procedures required the use of E10. As a
result, based on the information before us, we do not expect E15 to
raise emissions related materials compatibility issues for Tier 2 motor
vehicles.
Drivability and Operability
    There is no evidence from any of the test programs cited by Growth
Energy or in the data from the DOE Catalyst Study of driveability
issues for Tier 2 motor vehicles fueled with E15 that would indicate
that use of E15 would lead to increased emissions or that might cause
motor vehicle owners to want to tamper with the emission control system
of their motor vehicle. The Agency reviewed the data and reports from
the different test programs, and found no specific report of
driveability or operability issues across the many different motor
vehicles and duty cycles, including lab testing and in-use operation.

MY2000 and Older Light-Duty Motor Vehicles

    For MY2000 and older motor vehicles, the data and information
before EPA fail to adequately demonstrate that the impact of E15 on
exhaust emissions--both immediate and durability-related--will not
cause or contribute to violations of the emissions standards for these
motor vehicles. MY2000 and older motor vehicles do not have the
sophisticated emissions control systems of today's Tier 2 motor
vehicles, and there is an engineering basis to believe they may
experience conditions affecting catalyst durability that lead to
emission increases if operated on E15. This emissions impact, over
time, combined with the expected immediate increase in NOX
emissions from the use of E15, provides a clear basis for concern that
E15 could cause these motor vehicles to exceed their emissions
standards over their useful lives. Furthermore, some MY2000 and older
motor vehicles were likely designed for no more than limited exposure
to ethanol, since gasoline-ethanol blends were not used in most areas
of the country at the time they were designed. Their fuel systems,
evaporative emissions control systems, and internal engine components
may not have been designed and tested for long-term durability,
materials compatibility, or drivability with fuels containing ethanol.
The limited exhaust emissions durability test data, evaporative
emissions durability test data, and real-world materials compatibility
test data either provided by Growth Energy in their petition or
available in the public domain do not address or resolve these
concerns. Therefore, the information before the Agency is not adequate
to make the demonstration needed to grant a waiver for the introduction
into commerce of E15 for use in MY2000 and older light-duty motor
vehicles.

MY2001-2006 Light-Duty Motor Vehicles

    EPA is deferring a decision on MY2001-2006 light-duty motor
vehicles. DOE is in the process of conducting additional catalyst
durability testing that will provide data regarding MY2001-2006 motor
vehicles. The DOE testing is scheduled to be completed by the end of
November 2010. EPA will make the DOE test results available to the
public and consider the results and other available data and
information in making a determination on the introduction into commerce
of E15 for use in those model year motor vehicles. EPA expects to make
a determination for these motor vehicles shortly after the results of
DOE testing are available.

Nonroad Engines, Vehicles, and Equipment (Nonroad Products)

    The nonroad product market is extremely diverse. Nonroad products

with gasoline engines include lawn mowers, chainsaws, forklifts, boats,
personal watercraft, and all-terrain vehicles. Growth Energy did not
provide information needed to broadly assess the potential impact of
E15 on compliance of nonroad products with applicable emissions
standards. Nonroad products typically have more basic engine designs,
fuel systems, and controls than light-duty motor vehicles. The Agency
has reasons for concern with the use of E15 in nonroad products,
particularly with respect to long-term exhaust and evaporative
emissions durability and materials compatibility. The limited
information provided by Growth Energy and commenters, or otherwise
available in the public domain, did not alleviate these concerns. As
such, the Agency cannot grant a waiver for introduction into commerce
of E15 motor vehicle gasoline that is also for use in nonroad products.

Heavy-Duty Gasoline Engines and Vehicles

    Given their relatively small volume compared to light-duty motor
vehicles, heavy-duty gasoline engines and vehicles have not been the
focus of test programs and efforts to assess the potential impacts of
E15 on them. Growth Energy did not provide any data specifically
addressing how heavy-duty gasoline engines' and vehicles' emissions and
emissions control systems would be affected by the use of E15 over the
full useful lives of these vehicles and engines. Additionally, from a
historical perspective, the introduction of heavy-duty gasoline engine
and vehicle technology has lagged behind the implementation of similar
technology for light-duty motor vehicles. Similarly, emission standards
for this sector have lagged behind those of light-duty motor vehicles,
such that current heavy-duty gasoline engine standards remain
comparable, from a technology standpoint to older light-duty motor
vehicle standards. Consequently, we believe the concerns expressed
above regarding MY2000 and older motor vehicles are also applicable to
the majority of the in-use fleet of heavy-duty gasoline engines and
vehicles. As such, the Agency cannot grant a waiver for the
introduction into commerce of E15 for use in heavy-duty gasoline
engines and motor vehicles.

Highway and Off-Highway Motorcycles

    Like heavy-duty gasoline engines and vehicles, highway and off-
highway motorcycles have not been the focus of E15 test programs.
Growth Energy did not provide any data addressing how motorcycle
emissions and emissions control systems would specifically be affected
by the use of E15 over their full useful lives. While newer motorcycles
incorporate some of the advanced fuel system and emission control
technologies that are found in passenger cars and light-duty trucks,
such as electronic fuel injection and catalysts, many do not have the
specific control technology of today's motor vehicles (advanced fuel
trim control) that would allow them to adjust to the higher oxygen
content of E15. More importantly, older motorcycles do not have any of
these technologies and are therefore more on par with nonroad products
in some cases and MY2000 and older motor vehicles in others. As such,
the Agency cannot grant a waiver for the introduction into commerce of
E15 for use in highway and off-highway motorcycles.

Conditions on Today's Partial Waiver

    There are two types of conditions being placed on the partial
waiver being granted today: Those for mitigating the potential for
misfueling of E15 in all vehicles, engines and equipment for which E15
is not approved, and those addressing fuel and ethanol quality. All of
the conditions are discussed further below and are listed in Section
XII.
    EPA believes that the misfueling mitigation measures in the
proposed rule accompanying today's waiver decision would provide the
most practical way to ensure that E15 is only used in vehicles for
which it is approved. However, if any fuel or fuel additive
manufacturer desires to introduce into commerce E15, gasoline intended
for use as E15, or ethanol intended for blending with gasoline to
create E15, prior to the misfueling mitigation measures rule becoming
final and effective, they may do so provided they implement all of the
conditions of the partial waiver, including an EPA-approved plan that
demonstrates that the fuel or fuel additive manufacturer will implement
the misfueling mitigation conditions discussed below.

Misfueling Mitigation Notice of Proposed Rulemaking (NPRM)

    As mentioned above, EPA is proposing a regulatory program that
would help mitigate the potential for misfueling with E15 and promote
the successful introduction of E15 into commerce. The proposal includes
several provisions that parallel the misfueling mitigation conditions
on the E15 waiver. First, the proposed rule would prohibit the use of
gasoline-ethanol blended fuels containing greater than 10 vol% and up
to 15 vol% ethanol in vehicles and engines not covered by the partial
waiver for E15. Second, the proposed rule would require all fuel
dispensers to have a label if a retail station chooses to sell E15, and
it seeks comment on separate labeling requirements for blender pumps
and fuel pumps that dispense E85. Finally, the proposed rule would
require product transfer documents (PTDs) specifying ethanol content
and RVP to accompany the transfer of gasoline blended with ethanol as
well as a national survey of retail stations to ensure compliance with
the these requirements. In addition to proposing actions to mitigate
misfueling, the proposed rule would modify the Reformulated Gasoline
(``RFG'') program by updating the Complex Model to allow fuel
manufacturers to certify batches of gasoline containing up to 15 vol%
ethanol. Once adopted, these regulations would facilitate the
introduction of E15 into commerce under this partial waiver, as certain
requirements in the regulations would satisfy certain conditions in the
waiver. If EPA adopts such a rule, EPA would consider any appropriate
modifications to the conditions of this waiver.

II. Introduction

A. Statutory Background

    Section 211(f)(1) of the Clean Air Act (``CAA'' or ``the Act'')
makes it unlawful for any manufacturer of any fuel or fuel additive to
first introduce into commerce, or to increase the concentration in use
of, any fuel or fuel additive for use by any person in motor vehicles
manufactured after model year 1974 which is not substantially similar
to any fuel or fuel additive utilized in the certification of any model
year 1975, or subsequent model year, vehicle or engine under section
206 of the Act. The Environmental Protection Agency (``EPA'' or ``the
Agency'') last issued an interpretive rule on the phrase
``substantially similar'' at 73 FR 22281 (April 25, 2008). Generally
speaking, this interpretive rule describes the types of unleaded
gasoline that are likely to be considered ``substantially similar'' to
the unleaded gasoline utilized in EPA's certification program by
placing limits on a gasoline's chemical composition as well as its
physical properties, including the amount of alcohols and ethers
(oxygenates) that may be added to gasoline. Fuels that are found to be
``substantially similar'' to EPA's certification fuels may be
registered and introduced into commerce. The current ``substantially
similar'' interpretive rule for unleaded gasoline allows oxygen content
up to 2.7% by weight for certain

ethers and alcohols.\10\ E10 (a gasoline-ethanol blend containing 10
vol% ethanol) contains approximately 3.5% oxygen by weight and received
a waiver of this prohibition by operation of law under section
211(f)(4).\11\ E15 (gasoline-ethanol blended fuels containing greater
than 10 vol% ethanol and up to 15 vol% ethanol) has greater than 2.7
wt% oxygen content, and Growth Energy has applied for a waiver under
section 211(f)(4) of the Act.
---------------------------------------------------------------------------

    \10\ See 56 FR 5352 (February 11, 1991).
    \11\ As explained at 44 FR 20777 (April 6, 1979), EPA did not
grant or deny a waiver request for a fuel containing 90% unleaded
gasoline and 10% ethyl alcohol within 180 days of receiving that
request. By operation of a provision that was at that time included
in section 211(f)(4), E10 was no longer subject to the prohibitions
in CAA section 211(f)(1) of the Act. That provision has subsequently
been removed.
---------------------------------------------------------------------------

    Section 211(f)(4) of the Act provides that upon application of any
fuel or fuel additive manufacturer, the Administrator may waive the
prohibitions of section 211(f)(1) if the Administrator determines that
the applicant has established that such fuel or fuel additive, or a
specified concentration thereof, will not cause or contribute to a
failure of any emission control device or system (over the useful life
of the motor vehicle, motor vehicle engine, nonroad engine or nonroad
vehicle in which such device or system is used) to achieve compliance
by the vehicle or engine with the emission standards to which it has
been certified pursuant to sections 206 and 213(a). In other words, the
Administrator may grant a waiver for a prohibited fuel or fuel additive
if the applicant can demonstrate that the new fuel or fuel additive
will not cause or contribute to engines, vehicles or equipment to fail
to meet their emissions standards over their useful lives. The statute
requires that the Administrator shall take final action to grant or
deny the application, after public notice and comment, within 270 days
of receipt of the application.
    The current section 211(f)(4) reflects the following changes made
by the Energy Independence and Security Act of 2007: (1) Requires
consideration of the impact on nonroad engines and nonroad vehicles in
a waiver decision; (2) extends the period allowed for consideration of
the waiver request application from 180 days to 270 days; and, (3)
deletes a provision that resulted in a waiver request becoming
effective by operation of law if the Administrator made no decision on
the application within 180 days of receipt of the application.\12\
---------------------------------------------------------------------------

    \12\ As noted previously, the Energy Independence and Security
Act of 2007 also substantially increased the mandated renewable fuel
requirements of the Renewable Fuels Standard Program.
---------------------------------------------------------------------------

B. Growth Energy Application and Review Process

    On March 6, 2009, Growth Energy and 54 ethanol manufacturers
(hereafter ``Growth Energy'') submitted an application to the U.S.
Environmental Protection Agency (EPA) for a waiver of the substantially
similar prohibition. This application seeks a waiver for gasoline
containing up to 15 vol% ethanol. On April 21, 2009, EPA published
notice of the receipt of the application, and EPA requested public
comment on all aspects of the waiver application for assisting the
Administrator in determining whether the statutory basis for granting
the waiver request for E15 has been met.\13\ EPA originally provided a
30-day period for the public to respond. The deadline for public
comment was May 21, 2009.
---------------------------------------------------------------------------

    \13\ See 74 FR 18228 (April 21, 2009).
---------------------------------------------------------------------------

    After multiple requests for additional time to comment, EPA agreed
that additional time for comments was appropriate and that an extension
of the comment period would aid in providing these stakeholders and
others an adequate amount of time to respond to the complex legal and
technical issues that result from possibly allowing E15 to be sold
commercially. Accordingly, on May 20, 2009, EPA published a Federal
Register notice extending the public comment period for the E15 waiver
application until July 20, 2009.\14\ For EPA's response to more recent
requests for an additional comment period, see section IX.
---------------------------------------------------------------------------

    \14\ See 74 FR 23704 (May 20, 2009).
---------------------------------------------------------------------------

    The Agency received approximately 78,000 comments on the waiver
application. The overwhelming majority of these comments were brief
comments from individuals indicating either general support for or
opposition to the E15 waiver application. The Agency also received a
large number of comments from a variety of organizations which
substantively addressed the questions which EPA posed in the Federal
Register notice announcing receipt of the application. These comments
are summarized and addressed below.
    In addition to the information submitted by Growth Energy and
commenters, the Department of Energy (DOE) has been performing, and
continues to perform, testing on a variety of motor vehicles focused on
the effect E15 might have on motor vehicles after long-term use of E15
(``DOE Catalyst Study''). This testing is a significant source of
information on the effects of E15 on the durability of motor vehicles'
emissions control systems, a key technical issue to be addressed in
EPA's waiver review. This kind of testing requires thousands of miles
of mileage accumulation (or its equivalent using a test cell), and the
collection of such data requires a significant amount of time to
complete.
    Coordinating with EPA and stakeholders, DOE expedited the
durability testing, first focusing on newer motor vehicles. Realizing
that it would take a significant amount of time (months) to finish
collecting and evaluating the durability data, EPA notified Growth
Energy in a letter on November 30, 2009, that it was not issuing a
decision on the waiver at that time but instead planned to issue a
decision at a later date based on the need to assess the critical data
being generated by the DOE catalyst durability test program.
    The DOE Catalyst Study is comprehensive. A total of 82 vehicles are
expected to undergo full useful life testing. Motor vehicles are
accumulating mileage under an accelerated protocol, which generally
results in each motor vehicle being tested over 6-9 months. DOE has
completed the first phase of this testing which focused on light-duty
motor vehicles certified to Federal Tier 2 emissions standards. The
analysis and evaluation of not only this durability data, but all of
the data relevant to the Growth Energy application, as well as EPA's
partial waiver decision, is discussed and explained below. DOE should
complete testing on vehicles certified to National Low Emission Vehicle
(NLEV) and Tier 1 Federal emission standards by the end of November.
    Various parties have also suggested allowances for the use of E12
(gasoline-ethanol blended fuel that contains 12 vol% ethanol) for all
gasoline-powered vehicles and engines. The issue of E12 is also
discussed separately below in Section VIII.

C. Today's Notice of Proposed Rulemaking (NPRM) on Misfueling
Mitigation Measures

    As noted above, today's partial waiver decision places several
conditions on fuel and fuel additive manufacturers to mitigate the use
of E15 in nonroad products, highway and off-highway motorcycles, heavy-
duty gasoline engines and vehicles, and motor vehicles older than
MY2007.
    In a separate notice, we are today proposing regulatory provisions
that parallel many of the conditions placed on the E15 partial waiver.
Specifically, we are proposing a prohibition on the use of gasoline
containing greater than

10 vol% ethanol in MY2000 and older non-flex fueled light-duty motor
vehicles, heavy-duty gasoline engines and vehicles, highway and off-
highway motorcycles, and all nonroad products, based on findings under
both sections 211(c)(1)(A) and (B) of the CAA. The prohibition is
necessary based on the potential for increased emissions resulting from
the use of E15. In order to facilitate the entry of E15 into commerce
for use in MY2007 and newer motor vehicles, while protecting vehicles
and engines not approved for use of E15, this rulemaking proposes fuel
pump labeling provisions to mitigate the misfueling of motor vehicles
and other engines, vehicles and equipment prohibited from using a motor
vehicle gasoline containing ethanol in levels higher than E10. We are
also proposing additional requirements for fuels that contain greater
than 10 vol% ethanol and no more than 15 vol% ethanol, including the
proper documentation of ethanol content on product transfer documents
and requirements for a national survey to ensure the proper placement
of E15 labels and the proper placement of gasoline-ethanol blends in
the appropriate gasoline storage tanks; these provisions should help
support the effectiveness of a labeling program.

III. Method of Review

    Under section 211(f)(4) of the Act, 24 applications for waivers of
the section 211(f)(1) prohibitions have been received over the past 30
years. Of these, 23 applications have sought a waiver for additives for
unleaded gasoline. One application sought a waiver of the section
211(f)(1)(B) prohibitions for an additive to diesel fuel. Of these 24
applications, 11 applications were granted (some with conditions
attached), 10 were denied, and three were withdrawn by the applicant
prior to the Agency's decision.\15\
---------------------------------------------------------------------------

    \15\ ``Waiver Requests under Section 211(f) of the Clean Air Act
(Revised August 22, 1995),'' found at http://www.epa.gov/otaq/regs/
fuels/additive/waiver.pdf.
---------------------------------------------------------------------------

    Section 211(f)(4) clearly places upon the waiver applicant the
burden of establishing that its fuel or fuel additive will not cause or
contribute to the failure of vehicles or engines to meet their assigned
emission standards over their useful lives. Absent a sufficient
showing, the Administrator cannot make the required determination and
cannot grant the waiver. If interpreted literally, however, this burden
of proof would be virtually impossible for an applicant to meet as it
requires the proof of a negative proposition: That no vehicle or engine
will fail to meet emission standards to which it has been certified.
Such a literal interpretation could be construed as requiring the
testing of every vehicle or engine that will use the waived fuel.
Recognizing that Congress contemplated a workable waiver provision, EPA
has previously indicated that reliable statistical sampling and fleet
testing protocols could safely be used to demonstrate that a fuel or
fuel additive under consideration would not cause or contribute to
motor vehicles in the applicable national fleet failing to meet their
applicable emissions standards.\16\
---------------------------------------------------------------------------

    \16\ See 43 FR 41425 (September 18, 1978).
---------------------------------------------------------------------------

    While this demonstration typically takes the form of reliable
statistical sampling and fleet testing protocols, an applicant may also
make a demonstration based upon a reasonable theory regarding emissions
effects and support these judgments with confirmatory testing as an
alternative to providing the amount of data necessary to conduct robust
statistical analyses.\17\ If a reasonable theory exists, based on good
engineering judgment, which predicts the emission effects of a fuel or
fuel additive, an applicant may only need to conduct a sufficient
amount of testing to demonstrate the validity of such a theory. This
theory and confirmatory testing then form the basis from which the
Administrator may exercise his or her judgment on whether the fuel or
fuel additive will cause or contribute to a failure of the vehicles and
engines to achieve compliance with their emission standards.\18\ Thus,
the burden of proof calls for sufficient data to conduct statistical
analyses or to confirm a reasonable theory based on sound engineering
judgment.
---------------------------------------------------------------------------

    \17\ See 44 FR 12244 (February 23, 1979).
    \18\ See Waiver Decision on Application of E.I. DuPont de
Nemours and Company (DuPont), 46 FR 6124 (February 28, 1983).
---------------------------------------------------------------------------

    In determining whether a waiver applicant has established that the
proposed fuel or fuel additive will not cause or contribute to vehicles
and engines failing to meet their emission standards, EPA reviews all
of the material in the public docket. At a minimum, the docket includes
data submitted with the application and the public comments and data
received during the public review and comment period on the
application. EPA may also examine applicable data from any other
sources which may shed light on the relevant analyses; such other data
is also placed in the docket. EPA then considers and analyzes all of
the data to ascertain the emission effects of the fuel or fuel additive
on the applicable engines and vehicles.
    In conducting a waiver application review, EPA's emissions impact
analysis concentrates on the following four major areas: \19\ (1)
Exhaust emissions, both immediate and long-term (durability); (2)
evaporative emissions, both immediate and long-term; (3) materials
compatibility; and (4) driveability and operability. EPA evaluates the
emissions impacts in these four categories individually and
collectively and makes its final determination based on whether the new
fuel or fuel additive will cause or contribute to the failure of
vehicles and engines to meet their emissions standards. Each category
is further discussed below.
---------------------------------------------------------------------------

    \19\ See 44 FR 12244 (February 23, 1979).
---------------------------------------------------------------------------

    Exhaust and evaporative emission data are analyzed according to the
effects that a fuel or fuel additive is predicted to have on emissions
over time. If the fuel is predicted to have only an immediate effect on
emissions (i.e., the emission effects of the fuel or fuel additive are
immediate and remain constant throughout the life of the vehicle or
engine when operating on the waiver fuel), then ``back-to-back''
emissions testing will suffice. However, if the fuel or fuel additive
affects the operation of the engine or related emission control
hardware in a physical manner (e.g., operating temperatures, component
interaction, chemical changes, increased permeation, and materials
degradation) that might lead to emissions deterioration over time, test
data is needed to demonstrate that the long-term durability of the
emissions control system is not compromised by the fuel or fuel
additive such that it would cause or contribute to the engines or
vehicles failing to meet their emissions standards.
    Materials compatibility issues can lead to substantial exhaust and
evaporative emissions increases. In most cases, materials
incompatibility issues show up in emissions testing; however, there may
be impacts that do not show up due to the way the testing is performed
or because the tests simply do not capture the effect, especially if
materials compatibility effects are determined to result with use of
the new fuel or fuel additive over time. EPA has required applicants to
demonstrate that new fuel or fuel additives will not have materials
compatibility issues.\20\
---------------------------------------------------------------------------

    \20\ See 44 FR 1447 (January 5, 1979).
---------------------------------------------------------------------------

    A change in the driveability of a motor vehicle that results in
significant deviation from normal operation (i.e., stalling,
hesitation, etc.) could result in increased emissions. These increases

may not be demonstrated in the emission certification test cycles but
instead are present during in-use operation. In addition to consumer
dissatisfaction, a motor vehicle stall and subsequent restart can
result in a significant emissions increase because hydrocarbon (HC) and
CO emission rates are typically highest during cold starts. Further,
concerns exist if the consumer or operator tampers with the motor
vehicle in an attempt to correct the driveability issue since consumers
may attempt to modify a motor vehicle from its original certified
configuration.

IV. Waiver Submissions and Analysis of Light-Duty Motor Vehicle Issues

    This section discusses Growth Energy's waiver submission, comments
received on it, and EPA's waiver decision and analysis for light-duty
motor vehicles. The discussion groups vehicles according to our
decision: MY2007 and newer light-duty motor vehicles for which we are
approving the waiver, MY2001-2006 for which we are deferring a
decision, and MY2000 and older motor vehicles for which we are denying
the waiver.
    As described in Section III, Method of Review, above, the Agency
evaluated Growth Energy's waiver request and made its decision based on
four factors: (1) Exhaust emissions impact--both immediate and long-
term (known as durability); (2) immediate exhaust emissions impact; (2)
evaporative system impacts--both immediate and long-term; (3) the
impact of materials compatibility on emissions; and, (4) the impact of
drivability and operability on emissions.

A. MY2007 and Newer Light-Duty Motor Vehicles

    While this section discusses the rationale of our decision for
MY2007 and newer light-duty motor vehicles, it references information
related to other model years as Growth Energy's submission was not
model year specific and neither were the comments. In addition, we
believe it was important to discuss MY2007 and newer motor vehicles in
the context of how they are different from earlier model year light-
duty motor vehicles.
1. Exhaust Emissions--Long-Term Durability
a. Growth Energy's Submission
    For long-term durability testing (``durability testing''), Growth
Energy suggests that durability testing is not required for E15 for two
reasons. First, in its waiver application and public comments, Growth
Energy argued that emissions testing to determine the impact of long-
term use of E15 on the emissions control system is not required for E15
because EPA has waived durability testing for oxygenates in the past.
Growth Energy contends that EPA has determined that oxygenates such as
ethanol do not require durability testing because the Agency is
``unaware of any long-term deteriorative effects on exhaust emissions
associated with oxygenates'' \21\ and that ``the vast majority of data
indicate that the effect of oxygenates on exhaust emissions over time
has not been a significant issue.'' \22\ Growth Energy argued further
that it would be ``arbitrary and capricious'' for the Agency to require
durability testing for E15 considering EPA's long-standing position
that oxygenates like ethanol will not have long-term exhaust emissions
effects.
---------------------------------------------------------------------------

    \21\ See 53 FR 33846 (September 1, 1988).
    \22\ See 44 FR 10530 (February 21, 1979).
---------------------------------------------------------------------------

    Growth Energy's second argument is that EPA may accept reasonable
theoretical judgments regarding the emission effects of a fuel as an
alternative to direct testing of motor vehicles, and that in this case,
fuel volatility specification, limited durability emissions testing,
and data regarding materials compatibility and driveability could be
used to establish and confirm such a theory. Growth Energy suggests
that the collection of studies supplied in the application, coupled
with 30 years of experience using E10, provides a rational basis to
develop a theory that E15 will not cause or contribute to emissions
failures in motor vehicles. Growth Energy feels that the studies
supplied in the application supply enough data to confirm their theory
and this alleviates the need for long-term emissions testing.
    In particular, Growth Energy suggests that since a study conducted
by the Rochester Institute of Technology (RIT) \23\ examined the
effects of E20 (gasoline-ethanol blend containing 20 vol% ethanol) on
10 vehicles over significant mileage accumulation (75,000 miles
combined), and found no issues when comparing E20 emissions performance
with E0 (gasoline containing no ethanol) emissions performance, that
``E20 will not have a significant deteriorative effect on applicable
vehicle parts.'' \24\ Growth Energy believes that this is enough
information to satisfy long-term exhaust emissions testing
requirements. In its comments, Growth Energy supplied an updated
summary of the RIT Study which details RIT's expansion of the
driveability program to 400 motor vehicles. Growth Energy argues that
the updated summary of the RIT Study that they submitted in their
comments has shown ``no significant issues'' with over 400 motor
vehicles that have accumulated over 1.5 million total combined miles
and found that ``emissions may be reduced through use of E-20.'' \25\
Growth Energy contends that this study confirms their theory that E15
will not cause or contribute to motor vehicles failing their emissions
standards over their full useful lives.
---------------------------------------------------------------------------

    \23\ The effect of E20 ethanol fuel on vehicle emissions, B
Hilton and B Daddy, Center for Integrated Manufacturing Studies,
Rochester Institute of Technology, June 26, 2009. See EPA-HQ-OAR-
2009-0211. (``The RIT Study'').
    \24\ ``Application For A Waiver Pursuant to Section 211(f)(4) of
the Clean Air Act For E-15'' Submitted by Growth Energy on Behalf of
52 United States Ethanol Manufacturers; EPA Docket EPA-HQ-
OAR-2009-0211-0002.6.
    \25\ ``Growth Energy's Comments on Notice of Clean Air Act
Waiver Application To Increase the Allowable Ethanol Content of
Gasoline to Fifteen Percent,'' EPA Docket EPA-HQ-OAR-2009-
0211-2721.1.
---------------------------------------------------------------------------

b. Public Comment Summary
    Several commenters responded that the RIT Study has limitations and
does not alleviate concerns about the long-term emissions impacts of
using E15 in motor vehicles. The Manufacturers of Emissions Controls
Association (MECA) argues that emission control-related concerns
regarding the use of E15 include the potential for accelerated thermal
deactivation of three-way catalysts equipped on existing light-duty
motor vehicles or nonroad engines, due to higher exhaust temperatures
that have been observed on engines fueled with mid-level ethanol blends
in comparison to E0 and E10. MECA argues further that the thermal
durability of three-way catalyst formulations is a function of time,
catalyst temperature, and gas composition; extended catalyst exposure
to higher exhaust temperatures, especially in the presence of oxygen-
rich exhaust conditions that can be created through the use of E15, can
accelerate catalyst thermal deactivation mechanisms (e.g., sintering of
active precious metal sites, sintering of oxygen storage materials, and
migration of active materials into inert support materials).\26\
---------------------------------------------------------------------------

    \26\ ``Statement of the Manufacturers of Emission Controls
Association on the Waiver Request Received by the U.S. Environmental
Protection Agency to Increase the Ethanol Content of Gasoline up to
15%,'' EPA Docket EPA-HQ-OAR-2009-0211-2441.1.
---------------------------------------------------------------------------

    Many commenters point out that Growth Energy submitted and cited
only a summary of the RIT Study. The summary, as these commenters note,
omits key details necessary to evaluate the conclusions that Growth
Energy draws from the RIT Study. For example,

commenters noted that the summary did not specify the make, model and
year of the motor vehicles tested, making it impossible to determine
the representativeness of RIT's motor vehicle test fleet. Additionally,
they added that no actual data were included in the summary for
commenters and the Agency to conduct independent analyses of RIT's test
results. Furthermore, no detailed descriptions outlining the fuel
properties of both test fuels (E0 and E20) were included in the
summary. Even through Growth Energy provided an updated summary of the
RIT Study in its comments, this updated summary still omitted important
details necessary for commenters and the Agency to conduct an
independent analysis.
    Auto manufacturers, refiners, and several others similarly noted
that higher exhaust temperatures could cause increased deterioration of
catalysts over time. These commenters assert that this deterioration
may adversely affect a motor vehicle's ability to meet emissions
standards, particularly after significant mileage accumulation.
    Commenters noted that a recently released Coordinating Research
Council (CRC) Report E-87-1 (``the CRC Screening Study'' or ``E-87-1'')
is the first phase of another test program developed to look at the
effects of mid-level gasoline-ethanol blends on U.S. motor
vehicles.\27\ The purpose of the study was to identify motor vehicles
which used learned fuel trims to correct open-loop air-to-fuel (A/F)
ratios since this may gauge the risk of the catalyst to thermal
degradation.\28\ This study is the first phase of a two-phase study
evaluating the effects of mid-level gasoline-ethanol blends on emission
control systems. The test program identified and acquired a fleet of 25
test motor vehicles with 12 of those motor vehicles manufactured after
2000. The study collected vehicle speed, oxygen sensor A/F ratio, and
catalyst temperature data on four fuels (E0, E10, E15, and E20).
Results compared the three gasoline-ethanol blends with E0. The study
concluded that a large number of vehicles (12 of the 25 tested) failed
to apply long-term fuel trim to correct for increasing ethanol levels
when operating in open-loop control.
---------------------------------------------------------------------------

    \27\ Mid-level Ethanol Blends Catalyst Durability Study
Screening (CRC Report: E-87-1), June 2009 (``CRC Screening Study''),
EPA Docket  EPA-HQ-OAR-2009-0211-13970. Available at:
http://www.crcao.com/reports/recentstudies2009/E-87-1/E-87-
1%20Final%20Report%2007_06_2009.pdf.
    \28\ See section IV.A.1.c. for a detailed discussion of these
terms.
---------------------------------------------------------------------------

    Commenters also pointed out that the CRC Screening Study showed
increased exhaust temperatures in motor vehicles that failed to apply
long-term learned fuel trim when operating open loop at wide open
throttle using E15 and E20. This constituted seven of the sixteen
vehicles tested, and the average increase was 30 degrees Celsius in
these motor vehicles.
    Several comments refer to a series of studies conducted by Orbital
Engine Company for Environment Australia to evaluate impacts E20 would
have if introduced in Australia (``the Orbital Study''). The Orbital
Study evaluated emissions performance on total hydrocarbon, CO, NOx and
aldehydes, materials compatibility issues, and driveability of E20
compared to E0 with a test fleet of five paired late model Australian
motor vehicles. The Orbital Study completed emissions testing over
80,000 kilometers (about 50,000 miles). The study notes that there were
substantial increases in regulated pollutants for motor vehicles that
used E20 when compared with vehicles that used E0 after the
accumulation of 80,000 kilometers. The study's authors further point
out that one motor vehicle operating on E20 exceeded the Australian
NOX emissions standard.\29\ The Orbital authors also
examined catalyst efficiency changes as a possible cause of the changes
in emissions as a result of aging the motor vehicles on E20. The
Orbital authors conclude that the exhaust emissions increases occurred
due to catalyst degradation which they attribute to the increase in
exhaust temperature from E20 use during particular modes of operation.
They continue by noting that the two motor vehicles that experienced
dramatic emissions increases with E20 after aging were motor vehicle
models that failed to adjust to the higher oxygen levels found in E20.
---------------------------------------------------------------------------

    \29\ After reviewing the emissions results presented in the
Orbital Study, we believe that these motor vehicles' certified
emissions standards are comparable to the Tier 1 (1994 to 1999)
motor vehicle exhaust emissions standards in the United States.
---------------------------------------------------------------------------

    The Alliance of Automobile Manufacturers (``the Alliance'') reasons
that the Orbital Study, the CRC Screening Study, and the DOE Pilot
Study \30\ suggest that allowing the use of E15 in motor vehicles could
cause a substantial number of motor vehicles to fail emissions
standards because of increased catalyst deterioration over the motor
vehicles' full useful life, especially in so-called ``legacy vehicles''
which constitute a bulk of the American motor vehicle fleet. The
Alliance asserts that this uncertainty of the long-term effects of E15
on catalysts durability would require motor vehicle testing over the
full useful life to address these concerns. The Alliance for a Safe
Alternative Fuels Environment (``AllSAFE'') concluded that legally
``when the relevant effects can include accelerated catalyst
deterioration, 'back to back' testing to determine so-called
'immediate' emissions impacts is not sufficient.'' \31\
---------------------------------------------------------------------------

    \30\ In October 2008, DOE released a report titled Effects of
Intermediate Ethanol Blends on Legacy Vehicles and Small Non-road
Engines, Report 1. DOE later published an update to that report,
which included all of the original study plus additional vehicles.
For the purposes of this decision document, we refer to the updated
study, Effects of Intermediate Ethanol Blends on Legacy Vehicles and
Small Non-road Engines, Report 1--Updated, National Renewable Energy
Laboratory, February 2009, as the ``DOE Pilot Study''. EPA Docket
EPA-HQ-OAR-2005-0161-2880.
    \31\ ``Exhibit B, Supplemental Statutory Appendix To the
Comments of the Alliance for a Safe Alternative Fuels Environment On
the Request for Waiver of the Prohibition in Section 211(f)(1) of
the Clean Air Act
    Noticed for Comment at 74 FR 18,228 (April 21, 2009)'',
submitted by AllSAFE, EPA Docket EPA-HQ-OAR-2009-0211-
2559.2.
---------------------------------------------------------------------------

    Growth Energy submitted two responses to the Orbital Study. First,
Growth Energy commented that the motor vehicles tested in the Orbital
Study were designed for Australian emission standards and are not
representative of motor vehicles found in the US. Second, since much of
the research Orbital relied on was conducted in the 1980s and early
1990s, Growth Energy points out that the ``U.S. fleet has been
redesigned significantly since the mid-1980s to accommodate different
fuel blends and meet the world's most stringent emission regulations.''
\32\
---------------------------------------------------------------------------

    \32\ ``ATTACHMENT A: Responses to Anecdotes and Unfounded Claims
Regarding E-15,'' submitted by Growth Energy, EPA Docket
EPA-HQ-OAR-2009-0211-2721.2.
---------------------------------------------------------------------------

    Specifically addressing the issue of higher catalyst temperatures,
Growth Energy, ACE, and others responded in their respective comments
that higher catalyst temperatures are not necessarily harmful to the
catalysts.\33\ They point out that the catalyst temperature increases
in the DOE Pilot Study were relatively small and well within normal
operating temperatures. These commenters also note that the
temperatures only occurred in certain motor vehicles and only when
those motor vehicles were operated in the rarely used wide open
throttle mode. Growth Energy points out that for the seven motor
vehicles that adjusted for

the extra oxygen from the increased ethanol blends, catalyst
temperatures were cooler on average.
---------------------------------------------------------------------------

    \33\ In fact, ACE argues that these increased catalyst
temperatures may be responsible for the average decreases in
NOX emissions found in the DOE Study and RIT Study. See
ACE's Comment, 8.
---------------------------------------------------------------------------

c. EPA Response Regarding the Need for Long-Term Exhaust Emissions
(Durability) Testing
i. General Long-Term Exhaust Emissions (Durability) Concerns
    Ethanol impacts motor vehicles in two primary ways. First, as
discussed below, ethanol enleans the A/F ratio (increases the
proportion of oxygen relative to hydrocarbons) which can lead to
increased exhaust gas temperatures and potentially increase incremental
deterioration of emission control hardware and performance over time,
possibly causing catalyst failure. Second, ethanol can cause materials
compatibility issues, which may lead to other component failures (this
will be discussed further in sections IV.A.3 and IV.A.4 below).
Ultimately, either of these impacts may lead to emission increases.
    Due to the increased oxygen content of E15 relative to E10, motor
vehicles operated on E15 will likely run even leaner than those
operated on E10 depending on the vehicle technology and operating
conditions. It is also relevant to note that all motor vehicles are
emissions and durability tested for exhaust emissions certification
purposes using an E0 fuel; therefore, this effect of changing from E10
to E15 will not be present during certification and compliance testing.
Enleaned combustion leads to an increase in the temperature of the
exhaust gases. This increase in exhaust gas temperatures has the
potential to raise the temperatures of various exhaust system
components (e.g., exhaust valves, exhaust manifolds, catalysts, and
oxygen sensors) beyond their design limits. However, based on past
experience, the most sensitive component is likely the catalyst,
particularly in older motor vehicles with early catalyst technology.
Catalyst durability is highly dependent on temperature, time, and feed
gas composition. Catalyst temperatures must be controlled and catalyst
deterioration minimized during all motor vehicle operation modes for
the catalyst to maintain high conversion efficiency over the motor
vehicle's full useful life (FUL). This is particularly important during
high-load operation of a motor vehicle where the highest exhaust gas
temperatures are typically encountered and the risk for catalyst
deterioration is the greatest. Catalysts that exceed temperature
thresholds will deteriorate at rates higher than expected, compromising
the motor vehicles' ability to meet the required emission standards
over their FUL. Extended catalyst exposure to higher exhaust
temperatures can accelerate catalyst thermal deactivation mechanisms
(e.g., sintering of active precious metal sites, sintering of oxygen
storage materials, and migration of active materials into inert support
materials). While this damage can occur at a highly accelerated rate
with a sudden change in temperature (e.g., with a misfire allowing raw
fuel to reach the catalyst), it is more likely to occur over time from
elevated exhaust temperatures as may be experienced with frequent or
even occasional exposure to E15. This deterioration may adversely
affect a motor vehicle's ability to meet emissions standards,
particularly after significant mileage accumulation.
    Some motor vehicles may be designed in ways that manage catalyst
temperatures by compensating for the oxygen in the fuel under all
operating conditions, including high loads. This is achieved by using a
closed-loop fuel system that measures the A/F ratio and makes the
appropriate corrections to maintain the A/F ratio in the very tight
band of operation around stoichiometry necessary for optimum catalyst
performance and reductions in HC, CO, and NOX emissions. The
corrections can be applied to other areas of operation to achieve the
desired A/F ratio. The part of the closed-loop fuel system that is
responsible for the correction to the A/F ratio is referred to as
``fuel trim.'' The fuel trim adds or removes fuel to the engine in
order to maintain the required A/F ratio. If the measured A/F ratio has
insufficient oxygen or is ``rich,'' compared to what the engine needs,
the fuel trim will instruct the fuel injectors to inject less fuel,
making the A/F ratio ``leaner.'' The opposite is true if the measured
A/F ratio has too much oxygen and needs to inject more fuel for a
``richer'' A/F ratio. The fuel trim is generally comprised of two major
parts, short-term fuel trim and long-term or learned or adaptive fuel
trim. Learned or adaptive fuel trim can also be applied to open-loop
operation such as high-load or wide-open throttle to alleviate the
catalyst temperature increases caused by operating on E15. However this
practice has not been consistently employed by all manufacturers.
ii. Response to Growth Energy's First Argument
    In its first argument Growth Energy asserted that long-term exhaust
emissions testing (``durability testing'') is not required for E15
because EPA has waived durability testing for oxygenates in previous
waiver decisions. The Agency believes that Growth Energy's waiver
request application is different in substantial ways from previous
oxygenate waiver applications that EPA has reviewed. Previous oxygenate
waivers have, at most, resulted in increased fuel oxygen levels of up
to around 2.7% by weight oxygen. E15, for the first time, would add
significantly more oxygen to the fuel, up to around 5.5% by weight
oxygen depending on the density of the gasoline to which ethanol is
added. This increase in oxygen content is double the current oxygen
content limit that EPA interprets to be substantially similar to motor
vehicle gasoline used in the certification of motor vehicles.\34\
Additionally, with the exception of the original E10 waiver, which was
not granted through an EPA decision but through the operation of
law,\35\ and the Tertiary-butyl Alcohol waiver, which leads to oxygen
content of about 1.6 percent, EPA has placed a condition on all other
gasoline-alcohol waivers requiring a corrosion inhibitor to deal with
the aggressive nature of these fuels.
---------------------------------------------------------------------------

    \34\ See 73 FR 22277 (April 25, 2008).
    \35\ See 44 FR 20777 (April 6, 1979).
---------------------------------------------------------------------------

    In addition to this very large increase in oxygen content compared
to the waivers granted by EPA over 20 years ago, the emissions
standards that motor vehicles must achieve have become much more
stringent over time. As a result, emissions control systems have also
changed significantly over time. The emissions controls systems of
vehicles over the last 20 years have progressively become more
dependent on the ability to control the deterioration of the emissions
control system, especially the catalyst, to achieve compliance with the
emissions standards over the full useful life of the motor vehicle. Of
particular importance is the ability of emissions control systems over
time to limit or control long-term deterioration by accounting for the
oxygen level of the fuel. The oxygen content levels at issue in this
waiver application raise serious concerns about long-term durability.
This concern is supported by information in several studies.
    For both of these reasons, EPA rejects Growth Energy's claim that
long-term exhaust emissions (durability) testing is not required for
the E15 waiver request and that it would be arbitrary or capricious for
EPA to require durability testing for this waiver.

iii. Response to Growth Energy's Second Argument
    Growth Energy in its second argument concluded that E15 does not
require long-term exhaust emissions (durability) test data, because, as
they state, EPA may accept reasonable theoretical judgments as to the
emission effects of a fuel as an alternative to the direct testing of
motor vehicles. However, Growth Energy has not presented a reasonable
and valid engineering theory to demonstrate that E15 will not
detrimentally impact the durability of emissions control systems such
that engines and vehicles can still meet their emissions standards
while using E15. They point to fuel volatility specification, limited
durability emissions testing, data regarding materials compatibility
and driveability, as well as the collection of studies supplied in the
application, coupled with 30 years of experience with using E10, as
providing a rational basis for a theory that E15 would not cause long-
term deterioration of the emissions control systems of motor vehicles.
However, this is not an engineering theory or an engineering analysis.
Growth Energy has not analyzed the design of emissions control systems
and their changes over time, as emissions standards have increasingly
become more stringent. Nor has Growth Energy explained from an
engineering perspective why in theory the oxygen levels found in E15
should not lead to durability problems for the emissions control system
when used over time. Instead, Growth Energy points to the same
information as both the source of its theory as well as the data used
to confirm its theory. This highlights the circular nature of Growth
Energy's argument, as well as the absence of an engineering analysis
that identifies and explains any theory Growth Energy relies upon.
    Absent such a theory, one would perform the durability testing and
draw conclusions from such testing about the impact of E15 on long-term
durability. In essence, Growth Energy is suggesting that the data and
testing it presents provides such an evidentiary basis and is as
credible as data gathered from actual long-term durability testing for
drawing such conclusions. Instead of presenting a reasoned engineering
theory and data to confirm it, they are presenting what amounts to an
alternative evidentiary basis to long-term durability testing. However,
the information that Growth Energy relies on is not adequate to provide
such a basis.
    For example, the RIT Study that Growth Energy cites does not
support the conclusions that Growth Energy draws from this test
program. Specifically, Growth Energy argues that because the RIT Study
had run 10 motor vehicles over 75,000 miles without any serious issues,
a reasonable theory concerning E15's effects on long-term durability
may be inferred. However, 10 motor vehicles run over 75,000 miles on
E20 is only an average of 7,500 miles per motor vehicle. This is
substantially lower than the 100,000/120,000 full useful life of the
motor vehicles in the test program. Similarly, Growth Energy argues
that the expanded RIT Study ran 400 motor vehicles over 1.5 million
combined miles without significant issues. However, 400 motor vehicles
run over 1.5 million miles is an average of 3,750 miles per motor
vehicle. Additionally, Growth Energy suggests that RIT found decreases
in the emissions of regulated pollutants in RIT's 400-vehicle
driveability study, but no actual emissions testing on those motor
vehicles was performed. In the updated RIT summary that Growth Energy
submitted during the comment period, RIT had not conducted any
additional motor vehicle emissions testing since the earlier summary.
    Although the initial emissions testing conducted in 2008 may
suggest decreases in regulated pollutants, it does not address concerns
that increased ethanol levels in gasoline may lead to increased exhaust
temperatures, increased catalyst deterioration, and increased emissions
over time. Since the RIT study only performed emissions testing on 10
of the vehicles (4 of which were Ford F250 trucks), and the mileage
accumulated on E20 for each vehicle was far less than the 120,000 mile
FUL, it is not possible to draw adequate conclusions concerning long-
term emissions from the RIT Study even after the completion of the test
program.
    The Agency finds that none of the other studies or information
cited by Growth Energy specifically addresses the concern with the
effect of increased exhaust temperatures due to increased ethanol
levels and how that will impact the motor vehicles' ability to meet
their emissions standards over their useful life. The studies and
material may provide information relative to other aspects of ethanol
impacts but fall short of providing any substantive information on the
long-term effects of midlevel gasoline-ethanol blends on emissions
control systems. Nor do any of the studies that Growth Energy cites
provide sufficient information to lead the Agency to believe that there
will not be long-term durability concerns. Growth Energy did not
provide any data or analysis of warranty or repair information from in-
use experience with E10 vs. E0 with which to assess what the impact has
been over the last 30 years from the use of E10 in the in-use fleet,
nor any information showing how the results of such an analysis would
change with the use of E15. Therefore, we do not agree with Growth
Energy that durability testing is not required.
    The Agency concludes that the studies and other information cited
in Growth Energy's waiver request application, and its public comments,
do not demonstrate that E15 is not likely to have adverse impacts on
the long-term exhaust emissions (durability) of the emissions control
system over the full useful life of motor vehicles. The DOE Pilot
Study, the CRC Screening Study, the Orbital Study, comments from the
automobile manufacturers, and our engineering judgment, as discussed
below, all indicate that legitimate concerns exist that E15 could
accelerate the deterioration of the catalysts in a sizeable portion of
the national fleet, leading to increased emissions.
    Therefore, EPA finds that the limited durability testing and other
information relied upon by Growth Energy is not adequate by itself to
determine the long-term durability impact of E15 on exhaust emissions
control systems.
d. Durability Studies and EPA Analysis
    A number of regulatory actions have taken place since 2000 which
have placed an emphasis on real-world testing of motor vehicles, which
in turn has led to changes in emission control systems. First, the
Compliance Assurance Program, more commonly known as CAP2000, took
effect with MY2001 motor vehicles and was designed to place more
emphasis on the ``in-use'' performance (or the performance of motor
vehicles once they are in customer service) of motor vehicle emission
controls with motor vehicles operating nationwide on the different
available fuels. The In-Use Verification Program (IUVP) introduced
under CAP2000 requires manufacturers to perform exhaust and evaporative
emissions tests on customer motor vehicles at low and high mileage
intervals. This emphasis on real-world motor vehicle testing provided
manufacturers with increased incentive to consider the impacts of
different marketplace fuels, including E10, when developing and testing
their emissions control systems.
    Second, by MY2004, Supplemental Federal Test Procedure (SFTP)
emissions standards were fully phased in. SFTP emissions standards
expanded

vehicle emission testing to better represent actual consumer driving
habits and conditions by including the US06 test (a high speed and high
acceleration cycle), the SCO3 test (an air conditioning test cycle run
in an environmental test chamber at 95 [deg]F), and a 20 [deg]F cold
test run on the Federal Test Procedure (FTP) cycle. In response to
these requirements manufacturers developed more robust emissions
control systems (such as systems using wide range oxygen sensors)
capable of withstanding the higher temperatures experienced during
these more severe cycles without simply relying on enriching of the A/F
ratio, causing emissions to rise.
    Third, beginning with MY2004, the Agency implemented its current
and most stringent emission standards--the Tier 2 standards, with full
implementation for light-duty motor vehicles and trucks and medium duty
passenger motor vehicles completed by MY2007. Importantly, in order to
comply with Tier 2 full useful life requirements, additional changes
were required to ensure the durability of the exhaust and evaporative
emission control systems over ``real world'' conditions.
    As a result of all of these standards, Tier 2 motor vehicles (i.e.
motor vehicles subject to the Tier 2 standards) are more
technologically advanced and robust than cars built years ago. These
motor vehicles have improved hardware as well as more sophisticated
emissions control systems and strategies to help maintain catalyst
effectiveness throughout the extended motor vehicle operating range
over which emissions performance must be maintained. Motor vehicles now
have the ability to precisely adjust for changes in the A/F ratio of
the engine and ultimately maintain peak catalyst efficiency under
almost any condition, such as exposure to oxygenated fuels like those
containing ethanol. Auto manufacturers now warrant their new motor
vehicles to operate on gasoline-ethanol blends up to E10.
    While the Tier 2 regulations allowed new motor vehicles to phase-in
to the Tier 2 standards from MY2004-2009, actual manufacturer
certification data indicates that gasoline-fueled motor vehicles
reached full phase-in with MY2007. MY2004-2006 motor vehicles include a
mix of Tier 2 and ``interim non-Tier 2'' motor vehicles. Only some
flexible-fueled vehicles (FFVs) and diesel motor vehicles remained as
interim non-Tier 2 motor vehicles in MY2008 and 2009.
    To comply with the stringent Tier 2 standards, manufacturers must
minimize deterioration of the emissions control system over a motor
vehicle's FUL of 120,000 miles (40 CFR 86.1811-04). In particular,
catalyst deterioration must be minimized and catalyst temperatures
controlled during all motor vehicle operation modes for the catalyst to
work properly (i.e., for it to maintain the necessary high efficiency
demanded by the Tier 2 standards). To do so, some manufacturers
incorporated learned or adaptive fuel trim into their motor vehicle
designs to help control the A/F ratio and alleviate catalyst
temperature increases even under open-loop conditions. Others, through
careful hardware selection and certain calibration approaches, designed
their motor vehicles with higher thermal margins to accommodate the
effects of enleanment with gasoline-ethanol blends. Regardless of their
approach, all manufacturers have warranted their Tier 2 vehicles for
operation on E10, and we believe, based on available data, that they
are capable of operating on gasoline-ethanol blends up to E15 as well.
    The test data that has been collected supports our engineering
assessment. Several test programs were conducted by CRC, the National
Renewable Energy Laboratory (NREL), Oak Ridge National Laboratory and
DOE to study the effects of E15 on Tier 2 vehicles, with the key study
being the recently completed DOE Catalyst Study, discussed in more
detail below. The CRC Screening Study and the DOE Pilot Study measured
exhaust and catalyst temperature and/or evaluated the ability of motor
vehicles to apply learned fuel trim to adjust for the enleanment due to
ethanol during open-loop operation. As discussed above, leaner, hotter
exhaust subjects the catalyst to greater risk of high temperatures and
long-term catalyst deterioration and damage, and applying the learned
fuel trim to open-loop operation is one of several methods
manufacturers use to protect against this. Since roughly half of the
motor vehicles tested in these test programs, including roughly half of
the Tier 2 motor vehicles, did not apply learned fuel trim, and those
motor vehicles that did not apply learned fuel trim experienced higher
catalyst and exhaust temperatures with E15, these screening studies
highlighted the potential for concern. However, the lack of
compensating for ethanol content while in open-loop operation indicates
only the potential for temperature problems to occur, and elevated
temperatures only indicate the potential for catalyst deterioration;
motor vehicles that do not apply learned fuel trim may still have
sufficient thermal margins.
    To evaluate the actual impacts of E15 on Tier 2 motor vehicles, DOE
performed a catalyst durability test program,\36\ the DOE Catalyst
Study, throughout 2009 and 2010 on 19 Tier 2 motor vehicle models from
high sales volume models of the various light-duty motor vehicle
manufacturers. The specific purpose of the program was to evaluate the
long term effects of E0, E10, E15, and E20 on catalyst system
durability. The program also provided other limited but valuable
information relevant to today's partial waiver decision, such as
materials compatibility, evaporative control system integrity,
diagnostic system sensitivity and general driveability. Without the
results from this test program, EPA would not have had the information
necessary to properly assess the long-term exhaust emission
(durability) performance of E15. Program results indicate that the
changes manufacturers made (calibration, hardware, etc.) to their motor
vehicles to comply with the Tier 2 standards have in fact resulted in
the capability of the motor vehicle catalysts to withstand the
additional enleanment caused by E15, regardless of whether or not the
motor vehicles utilized learned fuel trim while in open-loop operation.
The test program results show that a representative cross section of
the Tier 2 fleet maintained their exhaust emission performance on E15
over the full useful life of the motor vehicles. The discussion which
follows contains a description of the DOE Catalyst Study and presents
and analyzes its results.
---------------------------------------------------------------------------

    \36\ Catalyst Durability Study, Department of Energy Tier 2
vehicle testing completed September 2010. Final report due early
2011.
---------------------------------------------------------------------------

i. DOE Catalyst Study Overview
    The Intermediate Ethanol Blends Emissions Controls Durability Test
Program (``DOE Catalyst Study'') was established in 2008, following
enactment of the Energy Independence and Security Act of 2007, to
investigate the potential impacts of gasoline-ethanol blend levels
above 10% on the durability of vehicle emissions control systems. The
program was subcontracted to Southwest Research Institute (SwRI),
Transportation Research Center (TRC) and Environmental Testing
Corporation (ETC).
ii. Vehicle Selection and Matching
    Several relevant criteria were used to determine the motor vehicle
models selected:

     Tier-2 compliant.
     Manufacturer and sales/registration volumes.
     Whether a motor vehicle did or did not apply learned fuel
trim (LFT or non-LFT, respectively) at wide-open throttle (WOT).
    Other studies also impacted selection: EPA's EPAct motor vehicle
study at Southwest Research Institute (SwRI) which was expanded into
the CRC's E-89 study,\37\ CRC's E-87-1 study (CRC Screening Study), and
the DOE Pilot Study. Based on the motor vehicle models EPA used to
represent the Tier 2 fleet in the CRC E-89 study, DOE consulted with
CRC and then instructed the national laboratories to utilize the same
set of motor vehicle models for the long-term durability studies, with
one exception (at the request of CRC, they switched out a Toyota Sienna
for a Nissan Quest).
---------------------------------------------------------------------------

    \37\ E-89, Energy Policy Act (EPAct) Light-duty Vehicle Fuel
Effects. (EPA and the National Renewable Energy Laboratory (NREL)
are sponsoring extensive testing of ethanol fuel effects in
connection with project E-89.)
---------------------------------------------------------------------------

    All the motor vehicles within a model set (one motor vehicle for
each fuel tested within a model) were matched to prevent confounding of
the data by undesirable motor vehicle attribute changes. The engine
family, engine displacement, evaporative emissions control family,
model year, powertrain control unit calibration, axle ratios, wheel
size, and tire size were constrained to be identical within a motor
vehicle set. Physical inspections of the motor vehicles to eliminate
obvious problematic motor vehicles (such as those with gross fluid
leaks, obvious and excessive body damage, etc.) were also a part of the
selection. Pre-owned motor vehicles' initial odometer readings were to
be within 10,000 miles amongst a motor vehicle set.
[GRAPHIC] [TIFF OMITTED] TN04NO10.000

iii. Fuels and Blending
    Emissions and related tests were conducted using an emissions
certification gasoline and splash blending batches of E10, E15, and E20
on site. The gasoline-ethanol blends were blended from emissions
certification gasoline and denatured fuel-grade ethanol. These
emissions test fuels were termed E0 (for ethanol-free emissions fuel),
E10 (for 10% ethanol emissions fuel), E15 (for 15% ethanol emissions
fuel) and E20 (for 20% ethanol emissions fuel).
    Aging fuels were produced by splash blending fuel-grade ethanol
with non-ethanol containing gasoline obtained commercially by the
subcontractors in their local area, rather than emissions certification
gasoline. The aging fuels were designated RE0, RE10, RE15, and RE20
with ``R'' conveying blending from retail gasoline.
iv. Emissions Test Protocol
    Motor vehicles were subjected to emissions (FTP) and related tests
at the following points during the test program: (1) At the beginning
of mileage accumulation; (2) at least one mid-mileage point; and (3) at
the end of mileage accumulation. DOE consulted with CRC on recommended
testing procedures. At SwRI and TRC, the acceptance tests also included
WOT tests to aid in classifying the vehicles as either LFT or non-LFT
motor vehicles. At each emissions test interval, duplicate FTP tests
were conducted on each motor vehicle using both the gasoline-ethanol
blend assigned to the motor vehicle as well as E0. (i.e. the ``E15''
motor vehicle received duplicate FTPs on both E15 and E0.) The motor
vehicles also underwent compression and leak-down checks at each
emissions interval. Tier 2 compliant motor vehicles were driven up to
their full-useful life (120,000 miles). The initial mileages of the
Tier 2 motor vehicles ranged from near zero to approximately 50,000
miles. These vehicles were driven approximately 70,000-120,000 miles
during the program.
    New motor vehicles were first aged to 4,000 miles to stabilize the
engine and emissions control systems, followed by the initial emissions
test. The motor vehicles then accumulated mileage until the first mid-
aging emissions tests at

60,000 miles. This cycle was then repeated to 90,000 miles for the
motor vehicles under test at ETC. At TRC and SwRI, the 90,000 mile
emissions tests were not conducted. All vehicles ended aging at 120,000
miles. Pre-owned motor vehicle sets with less than 70,000 miles at the
start were mid-aging tested at 95,000 miles with end-of-aging tests at
120,000 miles.
v. Mileage Accumulation
    The standard road cycle (SRC) was used for all aging. The SRC is
the official EPA driving cycle used for aging in the whole motor
vehicle exhaust durability procedure. This is a recommended EPA
procedure that the manufacturers regularly use for verifying full
useful life emissions capability. It has an average speed of 46.3 mph
and a maximum of 75 mph. The Nissan Quest aging was changed part way
through aging to a series of steady speed laps on the test track at TRC
at DOE's direction to accelerate completion of this motor vehicle set.
    ETC and SwRI used mileage accumulation dynamometers (MADs) for
aging. Motor vehicles at TRC were aged on a closed test track. Drivers
followed the SRC as they drove the motor vehicles around the track. To
complete the test program required motor vehicles to undergo anywhere
from six to nine months of mileage accumulation and emission testing.
vi. Powertrain Component Inspection
    At the end of motor vehicle mileage accumulations and emissions
testing at SwRI, six pairs of engines were disassembled and analyzed
for signs of wear and materials compatibility problems of concern with
gasoline-ethanol blends that might indicate durability concerns with
E15 that did not show up in the accelerated aging testing
performed.\38\ The eight different types of evaluations performed
included:
---------------------------------------------------------------------------

    \38\ Southwest Research Institute (SwRI) Project 08-58845 Status
Report, ``Powertrain Component Inspection from Mid-Level Blends
Vehicle Aging Study,'' September 6, 2010. EPA Docket EPA-
HQ-OAR-2009-0211-14016.
---------------------------------------------------------------------------

     Evaporative Emission System Integrity Check--a low
pressure smoke leak test.
     Evaporative Canister Butane Working Capacity Check.
     Cam Lobe Wear--measuring overall cam height to indicate
wear.
     Valve Seat Width and Valve Surface Contour--to measure
wear on the valve seat.
     Valve Stem Height--to assess valve seat recession.
     Intake Valve Deposit measurement.
     ASTM D5185 Analysis of Engine Oil Drain Samples--to assess
the presence of unusually high levels of wear metals.
     Fuel Pump Flow Evaluation.
vii. Summary and Conclusions of the Final Results of the DOE Catalyst
Study
    Tier 2 motor vehicle testing concluded in late September. Analysis
of the FUL emissions performance and emissions deterioration rates
showed no significant difference between the E0 and E15 fueled groups.
As shown in Tables 2 and 3 below, three E0 aged motor vehicles had
failing emissions levels at the end of the test program and one
additional motor vehicle failed one of several replicate tests. Two E15
aged motor vehicles had failing emissions levels at the end of the test
program. However, none of the emissions failures appeared to be
associated with the differences in the aging fuels. There were no
emissions component or material failures during aging that were related
to fueling. There was a catalyst efficiency fault code on an E0 motor
vehicle but not on the E15 counterpart.
---------------------------------------------------------------------------

    \39\ Our assessment of motor vehicles that exceeded emissions
standards at FUL mileage accumulation is that the exceedances were
not attributable to the fuel used.

                                             Table IV.A-2--E0 FUL Results Compared to Tier 2 Standards \39\
--------------------------------------------------------------------------------------------------------------------------------------------------------
         Year                   Model               LFT@WOT                   NOX                          NMOG                           CO
--------------------------------------------------------------------------------------------------------------------------------------------------------
2007.................  Accord.................               N   Pass........................  Pass........................  Pass.
2006.................  Silverado..............               Y   Pass........................  Pass........................  Pass.
2008.................  Altima.................               N   Pass........................  Fail........................  Pass.
2008.................  Taurus.................               Y   Pass........................  Pass........................  Pass.
2007.................  Caravan................               N   Pass........................  Pass........................  Pass.
2006.................  Cobalt.................               N   Pass........................  Pass........................  Pass.
2007.................  Caliber................               N   Fail........................  Pass........................  Pass.
2009.................  Civic..................               N   Pass........................  Pass........................  Pass.
2009.................  Explorer...............               Y   Pass........................  Pass........................  Pass.
2009.................  Corolla................               Y   Pass........................  Pass........................  Pass.
2009.................  Liberty................               N   Pass........................  Pass........................  Pass.
2005.................  Tundra.................               Y   Pass........................  Pass........................  Pass.
2006.................  Impala.................               Y   Pass........................  Pass........................  Pass.
2005.................  F150...................               Y   Pass........................  Pass........................  Pass.
2006.................  Quest..................               N   N/A.........................  N/A.........................  N/A.
2009.................  Outlook................               Y   Pass........................  Pass........................  Pass.
2009.................  Camry..................               Y   Pass........................  Pass........................  Pass.
2009.................  Focus..................               Y   Fail........................  Pass........................  Pass.
2009.................  Odyssey................               N   Pass *......................  Pass........................  Pass.
                       Total Fails............  ...............  2...........................  1...........................  0.
--------------------------------------------------------------------------------------------------------------------------------------------------------
* Denotes that average of emissions tests were below applicable FUL standard, but had at least one test value above the applicable FUL standard.

                          Table IV.A-3--E15 FUL Results Compared to Tier 2 Standards 40
----------------------------------------------------------------------------------------------------------------
    Year             Model             LFT@WOT              NOX                  NMOG                 CO
----------------------------------------------------------------------------------------------------------------
2007........  Accord.............               N   Pass...............  Pass...............  Pass.
2006........  Silverado..........               Y   Pass...............  Pass...............  Pass.
2008........  Altima.............               N   Pass...............  Pass...............  Pass.
2008........  Taurus.............               Y   Pass...............  Pass...............  Pass.

2007........  Caravan............               N   Pass...............  Pass...............  Pass.
2006........  Cobalt.............               N   Pass...............  Pass...............  Pass.
2007........  Caliber............               N   Pass...............  Pass...............  Pass.
2009........  Civic..............               N   Pass...............  Pass...............  Pass.
2009........  Explorer...........               Y   Pass...............  Pass...............  Pass.
2009........  Corolla............               Y   Pass...............  Pass...............  Pass.
2009........  Liberty............               N   Pass...............  Pass...............  Pass.
2005........  Tundra.............               Y   Pass...............  Pass...............  Pass.
2006........  Impala.............               Y   Pass...............  Pass...............  Pass.
2005........  F150...............               Y   Pass...............  Pass...............  Pass.
2006........  Quest..............               N   Fail...............  Pass...............  Pass.
2009........  Outlook............               Y   Pass...............  Pass...............  Pass.
2009........  Camry..............               Y   Pass...............  Pass...............  Pass.
2009........  Focus..............               Y   Fail...............  Pass...............  Pass.
2009........  Odyssey............               N   Pass...............  Pass...............  Pass.
              Total Fails........  ...............  2..................  0..................  0.
----------------------------------------------------------------------------------------------------------------
* Denotes that average of emissions tests were below applicable FUL standard, but had at least one test value
  above the applicable FUL standard.

    Using standard statistical tools, the resulting test results shown
in Tables IV.A-2 and IV.A-3 support the conclusion that E15 does not
cause Tier 2 motor vehicles to exceed their exhaust emission standards
over their useful life.
---------------------------------------------------------------------------

    \40\ Our assessment of motor vehicles that exceeded emissions
standards at FUL mileage accumulation is that the exceedances were
not attributable to the fuel used.
---------------------------------------------------------------------------

    We performed a statistical analysis of this emission data to assess
the impact of E15 on the rate of deterioration of exhaust emissions. We
used a general linear model in SPSS\TM\ to perform this analysis. Each
individual test motor vehicle was allowed its own base level of
emissions (e.g., the Taurus aged on E0 was allowed one base emission
level and the Taurus aged on E15 was allowed a different base emission
level). This reflects the fact that individual motor vehicles, even of
the same design, have emissions levels that differ to at least the same
order of magnitude as the effect of fuel quality on emissions. Each
model type (e.g., all of the Taurus motor vehicles as a group) was also
allowed its own rate of emissions deterioration. This reflects the fact
that motor vehicle design has a significant impact on the rate of
emissions deterioration. We then tested the hypothesis that the effect
of aging the motor vehicle on E15 caused a non-zero change in the rate
of change in non-methane organic gases (NMOG) and NOX
emissions. Each emission test was weighted to reflect the number of
replicates performed on that motor vehicle at a specific mileage test
point. For example, if only two replicate tests were performed on the
Taurus aged on E0 at it mid-level test point (i.e., 67,000 miles), then
each emission test was assigned a weight of 0.5. If three replicate
tests were performed at that mileage, then each emission test was
assigned a weight of 0.33.
    The statistical analysis of the remaining Tier 2 exhaust emission
data indicated that the rate of deterioration in NMOG emissions
decreased on average, while that for NOX emissions
increased. However, the impacts were not statistically significant
deterioration at the 90% confidence level.\41\ Thus, due to the
variability in the effect across the various test motor vehicles, we
cannot confidently reject the hypothesis that the emission
deterioration rates on both blends are the same. In other words, there
is a significant chance that the average impacts observed are the
result of the randomness in the data. This conclusion is supported by
the fact that the average changes in NMOG and NOX emissions
deterioration rates went in opposite directions. If the catalysts had
in fact been deteriorating faster with E15, then all emissions should
have deteriorated consistently. Therefore, the catalyst durability test
program results also support the conclusion that E15 will not
contribute to Tier 2 motor vehicles exceeding their emission standards
over their full useful life. The details of this statistical analysis
can be found in an EPA Technical Summary located in the docket to this
waiver decision.\42\
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    \41\ The Agency has typically used a confidence level of 90% in
CAA section 211(f)(4) waiver requests instead of the more
conventional 95% confidence level. We feel that the 90% confidence
level increases the likelihood that increases in deterioration would
be statistically significant and therefore would be more
conservative in this case. However, these differences are also not
statistically significant at the 95% confidence level.
    \42\ Technical Summary of DOE Study on E15 Impacts On Tier 2
Vehicles and Southwest Research Teardown Report. EPA Docket
EPA-HQ-OAR-2009-0211.
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    The results of the vehicle tear-down inspections were analyzed to
assess whether E15 exhibited any signs of wear or materials
incompatibility that might indicate durability concerns that could lead
to elevated exhaust or evaporative emissions that might not have shown
up in the FUL emission testing performed.\43\ For seven of the eight
evaluations performed, there were no apparent differences at the end-
of-life between the motor vehicles that were operated on E15 and E0.
While individual motor vehicle results varied (as one would expect in
inspections such as this), there was no pattern that would suggest
greater deterioration on E15, and none of the measurements indicated
are a cause for a concern over powertrain durability for the Tier 2
motor vehicles evaluated. The one area where motor vehicles aged on E15
differed in their results was intake valve deposits. E15 showed a
consistent and often significant increase in intake valve deposits in
comparison to E0. This is not surprising given that prior detergent
additive studies have shown E10 to be a more severe test fuel for
intake valve deposits than E0. For this very reason the fuel on which
fuel additive manufacturers must certify their detergent additive
packages contains 10 vol% ethanol. Since the Tier 2 motor vehicles did
not show increased exhaust emission deterioration over their FUL with
E15 in comparison to E0, the increased intake valve deposits do not
appear to have lead to a corresponding emissions increase. As a result,
the finding that E15 leads to increased intake valve deposits appears
to be primarily an issue to be addressed in

future gasoline detergent additive formulations.
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    \43\ Ibid.
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    Finally, the CRC engine durability study \44\ has limited relevance
for the waiver decision because it used only E20 fuel. Initial data is
for eight motor vehicles ranging from MY2001-2009 with initial mileage
as high as 110,000 miles. The engines were removed and dynamometer-aged
for 500 hours with 50% of the time at wide-open throttle (3500 rpm).
Since the study used only E20 fuel and did not test matching engines
aged on E0, there is no way to determine the influence of the fuel
blend on engine deterioration. There were some elevated leakdown
measurements observed in the study but there is no way to determine if
they were fuel blend related or would have occurred even with E0 fuel.
Also, several motor vehicles were listed as failing the leak tests yet
the motor vehicles passed the leak test at later points in the study.
In any event, all the engines that completed aging passed their motor
vehicle emissions tests.
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    \44\ CRC Project No. CM-136-09-1B Engine Durability Study of
Mid-Level Ethanol blends, EPA Docket EPA-HQ-OAR-2009-0211-
14003.5.
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2. Exhaust Emissions--Immediate Effects for MY2007 and Newer Light-Duty
Motor Vehicles
    Instantaneous or immediate impacts of a fuel or fuel additive are
those that are experienced essentially immediately upon switching from
the original fuel. In the case of this partial waiver decision, the
immediate exhaust emission impacts of interest are those that are
caused by E15 in comparison to E0, which is the fuel on which the motor
vehicles were certified. The immediate exhaust emission impacts must be
taken into consideration along with the long-term or durability
emission impacts discussed in the previous section in assessing the
waiver. This section discusses the immediate exhaust emission impacts
on MY2007 and newer light-duty motor vehicles. Discussion of immediate
exhaust emission impacts on other motor vehicles is addressed in their
respective sections. However, since Growth Energy's submission and
information supplied by commenters regarding immediate emission impacts
of E15 were not specific to the model year of the motor vehicles, this
section also contains much of the information on immediate emission
impacts for other vehicles as well.
a. Growth Energy's Submission
    Growth Energy supplied data produced from several test programs
that measured the immediate emission impacts of E15 on motor vehicles
spanning a range of model years, including several Tier 2 motor
vehicles. Growth Energy claims that the ACE Study.\45\ the RIT Study,
the Minnesota Center for Automotive Research (MCAR) Study,\46\ and a
DOE Pilot Study show that E15 results in decreased emissions of
NOX, non-methane hydrocarbons (NMHC), and CO on average, and
no increase in NMOG emissions when compared to E0. Growth Energy argues
that these studies demonstrate that E15 will not cause or contribute to
the failure of motor vehicles to meet their emissions standards. While
much of the data cited by Growth Energy was on E20, they argued that
because the studies they submitted with their application show
favorable emissions performance on gasoline-ethanol blends that
contained higher than 15 vol% ethanol (i.e., E20), those results should
be applicable to E15 by interpolation.
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    \45\ Optimal Ethanol Blend-level Investigation, Final Report
prepared by Energy & Environmental Research Center and Minnesota
Center for Automotive research for American Coalition for Ethanol
``ACE Study''. EPA Docket  EPA-HQ-OAR-2009-0211-0002.26.
    \46\ Use of Mid-Range Ethanol/Gasoline Blends in Unmodified
Passenger Cars and Light Duty Trucks, prepared by Minnesota Center
for Automotive research July 1999 ``MCARStudy.'' EPA Docket
EPA-HQ-OAR-2009-0211-0002.24.
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b. Public Comment Summary
    The Alliance of Automobile Manufacturers (``The Alliance'') and
several others commented that EPA has repeatedly outlined in past
waiver decisions and public presentations important methodological
considerations necessary to conduct a rigorous test program which would
provide data sufficient to satisfy waiver criteria.\47\ Comments from
the Alliance describe the data requirements EPA has required in the
past, specifically noting that those test programs required the
following: (1) Use representative test fleets of motor vehicles
available in the market; (2) conduct back-to-back motor vehicle pair
testing to control for variability; (3) compare test fuel results with
a baseline certification fuel; (4) use Federal certification test
procedures (FTP) for emissions testing; (5) evaluate emissions effects
over the full useful life for durability testing through real-world
aging; and (6) perform statistical analyses to provide defensible
results. The Alliance went on in their comments to highlight
deficiencies in one or more of these data requirements in each of the
studies cited by Growth Energy.
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    \47\ See Alliance of Automobile Manufacturers Comments, National
Petrochemical and Refiners Association, the American Petroleum
Institute's Comments, and the Alliance for the Safe Alternative
Fuels Environment comments in EPA Docket EPA-HQ-OAR-2009-
0211.
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    Additionally, the Alliance and others argue that none of the
studies submitted by Growth Energy used nationally ``representative''
test fleets. The Alliance points out that the American automobile fleet
takes about 20 years to turn over, and that a well-executed study
should have a test fleet that is proportionally similar to the model
years that comprise the national fleet. The Alliance argues that a bulk
of the emissions data cited in Growth Energy's waiver request focus on
newer (i.e., Tier 2) motor vehicles and do not adequately represent the
national motor vehicle fleet and that these older motor vehicles may be
more sensitive to the effects of higher gasoline-ethanol blends and
constitute a greater portion of the number of motor vehicles currently
in use. Many comments recommend that the Agency deny Growth Energy's
request based on the potentially adverse effects of E15 on older motor
vehicles.
    Several commenters, including the automobile manufacturers,
petroleum refiners, environmental organizations and State agencies,
noted the expected linear relationship between ethanol content in
gasoline-ethanol blends and increased NOX emissions. These
commenters pointed out that the EPA Predictive Models, MOVES model and
the MOBILE6.2 model all predicted increased NOX emissions as
a gasoline-ethanol blend increases the ethanol content. These models
are used for air quality modeling purposes for compliance with State
and Federal air quality standards and are based on comprehensive motor
vehicle testing spanning decades. These commenters argued further that
these increases in NOX may cause a sizable portion of the
motor vehicle fleet to exceed emissions standards, especially if a
motor vehicle was close to the emissions standard.
c. EPA Analysis
    The Agency agrees with commenters that there are several
limitations of the studies cited by Growth Energy and/or the analyses
they performed, which undermine their conclusions. The ACE study cited
by Growth Energy does not provide useful information to assess the
emissions performance of motor vehicles for purposes of this waiver
decision since it tested three non-flex fuel Tier 2 motor vehicles
primarily under high-speed and high-load conditions, atypical of most
in-use motor vehicle operation and not representative of motor vehicle
certification conditions. The study likely shows that the high heat of
vaporization and high octane of ethanol

can enhance vehicle performance under wide-open throttle conditions and
high loads, but the Agency believes that it is not relevant for
evaluating emissions under normal operating conditions as observed on
properly loaded motor vehicles tested on certification test cycles
generally required for a waiver emission impacts demonstration.
    The RIT Study cited by Growth Energy was an interim report of
ongoing work in which E0 and E20 fuels were tested in 10 1998-2004
model year motor vehicles from the Monroe County Fleet Center, none of
which were designed to comply with Tier 2 emission standards. The
emissions testing performed at the time of Growth Energy's application
failed to properly measure emissions related to the ethanol (i.e.,
alcohols and aldehydes) which contribute to the NMOG emissions.
Furthermore, the testing schedule did not perform back-to-back testing
of the different fuels at common motor vehicle mileage intervals, thus
confounding fuel and normal deterioration effects. As discussed below,
we believe these shortcomings were subsequently corrected in later
testing through the support of the NREL, but the data cited by Growth
Energy could not be used to quantify the immediate emissions impacts of
E15.
    The MCAR Study cited by Growth Energy tested 15 motor vehicles of
various model years from 1985 to 1998. However, the emissions were
measured over only a hot portion of the certification cycle and the
individual test results needed for analysis were never submitted or
made available to the Agency. Therefore, it could not be used to
compare the emissions performance of the motor vehicles to the
emissions standards. Furthermore, since only E10 and E30 were tested,
it cannot be used to quantify the immediate emission impacts relative
to the official E0 certification fuel.
    Only the DOE Pilot Study cited by Growth Energy provides useful
information for assessing the immediate exhaust emission impacts of
E15. It measured emissions from 16 vehicles, including seven Tier 2
compliant motor vehicles, on E0, E10, E15, and E20 splash blends over
the LA92 drive cycle. However, even it is of limited usefulness in
drawing conclusions regarding the impact of E15 across the large in-use
motor vehicle fleet due to the limited size and nature of the test
program (fleet makeup, test fuels). The DOE Pilot Study was not
designed to quantify the emissions impact across the fleet but instead
to probe a limited sample of high sales volume motor vehicles certified
to different emission standards for any immediate emission problems. By
itself, it is not a basis for drawing any definitive conclusions with
respect to E15 emissions performance.
    Thus, each of the individual studies is of limited value in
evaluating the immediate emissions impact of E15 across the various
groups of motor vehicles at issue in this partial waiver decision. As a
group, these studies are no stronger as they do not fill the gaps in
each of the various studies. Therefore, the Agency does not believe
that the studies submitted by Growth Energy adequately support the
conclusions that Growth Energy drew from them regarding the immediate
exhaust emission impacts from using E15. At the same time, the Agency
believes that there is sufficient data and information available to
demonstrate that the immediate emissions impact of E15 follows the same
pattern as E10 in that there will be a decrease in NMOG (as well as
NMHC and total HC) and CO emissions and an increase in NOX
emissions. While the magnitude of the NOX emissions increase
is greater with E15 it is still not enough to cause at least Tier 2
compliant motor vehicles to violate their NOX emissions
standard.
    There is a long history of test programs that have been carried out
on light-duty motor vehicles and trucks that have quantified the
emission impacts of blending ethanol up to 10 vol% into gasoline. These
test programs, dating back to the earliest days of gasoline-ethanol
blends, have found that the oxygen content of ethanol enleans the A/F
ratio in motor vehicles during open-loop operation, causing a decrease
in HC and CO emissions, but also results in a corresponding increase in
NOX emissions. These test programs have also shown that
during normal closed-loop operation the combustion characteristics of
ethanol contribute to small increases in NOX emissions.
There are other factors that can play into the emission impacts, such
as other changes to gasoline that occur or are made when ethanol is
added, the high heat of vaporization and high octane of ethanol, and
the design and control algorithms of the motor vehicle. However,
similar emission trends with ethanol have been seen consistently in
most carefully controlled and properly conducted studies. These studies
have been used to develop emission models, such as the EPA Predictive