Document ID: EPA-HQ-OAR-2004-0072-0084
Agency: epa
Document Type: Rule
Title: In-Use Testing for Heavy-Duty Diesel Engines and Vehicles; Emission Measurement Accuracy Margins for Portable Emission Measurement Systems and Program Revisions
Posted Date: 2008-03-13T04:00Z

[Federal Register: March 13, 2008 (Volume 73, Number 50)]
[Rules and Regulations]               
[Page 13441-13452]
From the Federal Register Online via GPO Access [wais.access.gpo.gov]
[DOCID:fr13mr08-6]                         

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ENVIRONMENTAL PROTECTION AGENCY

40 CFR Part 86

[EPA-HQ-OAR-2004-0072; FRL-8539-3]
RIN 2060-A-069

 
In-Use Testing for Heavy-Duty Diesel Engines and Vehicles; 
Emission Measurement Accuracy Margins for Portable Emission Measurement 
Systems and Program Revisions

AGENCY: Environmental Protection Agency (EPA).

ACTION: Direct final rule.

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SUMMARY: In a rule published on June 14, 2005, EPA established a 
manufacturer-run, in-use testing program for heavy-duty diesel 
vehicles. The program requires engine manufacturers to measure exhaust 
emissions from their diesel engines using portable emissions 
measurement systems during real-world operation. At the time the rule 
was promulgated, EPA established interim emission measurement 
``accuracy'' margins for the requisite portable emission measurement 
devices pending the development of final accuracy margins through a 
comprehensive research program. This Direct Final Rule adopts the 
resulting final accuracy margins for gaseous pollutants. Also, this 
rule makes several changes to the program in the early years of in-use 
testing. First, we are eliminating the first calendar year, i.e., 2006, 
of the two-year pilot program for particulate emissions (PM) in 
response to engine manufacturers' concerns, which primarily relate to 
the availability and efficacy of the requisite portable measurement 
systems (PEMS) for that pollutant. Second, due to a delay in developing 
the final accuracy margin for PM under the aforementioned comprehensive 
research program, we are delaying the first year of the fully 
enforceable PM test program from the 2008 calendar year to the 2009 
calendar year. During the 2008 calendar year, there will be another 
year of pilot program testing for that pollutant. Third, and finally, 
we are extending the normal period for reporting in-use test results 
during the initial years of the program and allowing certain short-term 
changes in how vehicles are recruited and tested. These revisions are 
primarily intended to address delays in initiating the gaseous emission 
and PM pilot programs, manufacuturers' concerns regarding the schedule 
for initial purchases of PM measurement systems, and manufacturers' 
concerns regarding potential difficulties of initially instrumenting 
vehicles with these units.

DATES: This is effective on May 12, 2008 without further notice, unless 
EPA receives adverse comment by April 14, 2008. If EPA receives adverse 
comment, we will publish a timely withdrawal of the Direct Final Rule 
in the Federal Register informing the public that the rule will not 
take effect.

ADDRESSES: Submit your comments, identified by Docket ID No. EPA-HQ-
OAR-2004-0072, by one of the following methods:
     www.regulations.gov: Follow the on-line instructions for 
submitting comments.
     E-mail: a-and-r-docket@epa.gov.
     Fax: (202) 566-9744.
     Mail: Environmental Protection Agency, Mail Code: 2822T, 
1200 Pennsylvania Ave., NW., Washington, DC 20460. Please include two 
copies.
     Hand Delivery: U.S. Environmental Protection Agency, EPA 
Headquarters Library, EPA West Building, Room: 3334, 1301 Constitution 
Avenue, NW., Washington, DC. Such deliveries are only accepted during 
the Docket's normal hours of operation, and special arrangements should 
be made for deliveries of boxed information.
    Instructions: Direct your comments to Docket ID No. EPA-HQ-OAR-
2004-0072. EPA's policy is that all comments received will be included 
in the public docket without change and may be made available online at 
www.regulations.gov, including any personal information provided, 
unless the comment includes information claimed to be Confidential 
Business Information (CBI) or other information whose disclosure is 
restricted by statute. Do not submit information that you consider to 
be CBI or otherwise protected through www.regulations.gov or e-mail. 
The www.regulations.gov Web site is an ``anonymous access'' system, 
which means EPA will not know your identity or contact information 
unless you provide it in the body of your comment. If you send an e-
mail comment directly to EPA without going through www.regulations.gov 
your e-mail address will be automatically captured and included as part 
of the comment that is placed in the public docket and made available 
on the Internet. If you submit an electronic comment, EPA recommends 
that you include your name and other contact information in the body of 
your comment and with any disk or CD-ROM you submit. If EPA cannot read 
your comment due to technical difficulties and cannot contact you for 
clarification, EPA may not be able to consider your comment. Electronic 
files should avoid the use of special characters, any form of 
encryption, and be free of any defects or viruses. For additional 
information about EPA's public docket visit the EPA Docket Center 
homepage at http://www.epa.gov/oar/dockets.html.
    Docket: All documents in the docket are listed in the 
www.regulations.gov index. Although listed in the index, some 
information is not publicly available, e.g., CBI or other information 
whose disclosure is restricted by statute. Certain other material, such 
as copyrighted material, will be publicly available only in hard copy. 
Publicly available docket materials are available either electronically 
in www.regulations.gov or in hard copy at the EPA Docket Center, EPA 
West Building, EPA Headquarters Library, Room 3334, 1301 Constitution 
Avenue, NW., Washington, DC. The Public Reading Room is open from 8:30 
a.m. to 4:30 p.m., Monday through Friday, excluding legal holidays. The 
telephone

[[Page 13442]]

number for the Public Reading Room is (202) 566-1744, and the telephone 
number for the Air Docket is (202) 566-1742.

FOR FURTHER INFORMATION CONTACT: Richard Wilcox, Assessment and 
Standards Division, Office of Transportation and Air Quality, 2000 
Traverwood Drive, Ann Arbor, MI 48105; telephone number: (734) 214-
4390; fax number: (734) 214-4939; e-mail address: wilcox.rich@epa.gov.

SUPPLEMENTARY INFORMATION: 

I. Why Is EPA Using a Direct Final Rule?

    EPA is publishing this rule without a prior proposal because we 
view this action as noncontroversial and anticipate no adverse comment. 
However, in the ``Proposed Rules'' section of today's Federal Register 
publication, we are publishing a separate document that will serve as 
the proposal to adopt the provisions in this Direct Final Rule if 
adverse comments are received on this rule. We will not institute a 
second comment period on this action, however. Any parties interested 
in commenting must do so at this time. For further information about 
commenting on this rule, see the ADDRESSES section of this document.
    If EPA receives adverse comment or a request for public hearing, we 
will publish a timely withdrawal in the Federal Register informing the 
public that this direct final rule will not take effect. We would 
address all public comments in any subsequent final rule based on the 
proposed rule.

II. Does This Action Apply to Me?

    This action will affect companies that manufacture and certify all-
terrain vehicles for sale in the United States.

------------------------------------------------------------------------
                                                        Examples of
           Category              NAICS code \a\     potentially affected
                                                          entities
------------------------------------------------------------------------
Industry.....................      336112; 336120  Engine and Truck
                                                    Manufacturers.
Industry.....................      811112; 811198  Independent
                                                    commercial importers
                                                    of vehicles and
                                                    parts.
------------------------------------------------------------------------
\a\ North American Industry Classification System (NAICS).

    To determine whether particular activities may be affected by this 
action, you should carefully examine the regulations. You may direct 
questions regarding the applicability of this action as noted in FOR 
FURTHER INFORMATION CONTACT.

III. What Should I Consider as I Prepare My Comments for EPA?

    A. Submitting CBI. Do not submit this information to EPA through 
www.regulations.gov or e-mail. Clearly mark the part or all of the 
information that you claim to be CBI. For CBI information in a disk or 
CD-ROM that you mail to EPA, mark the outside of the disk or CD-ROM as 
CBI and then identify electronically within the disk or CD-ROM the 
specific information that is claimed as (CBI). In addition to one 
complete version of the comment that includes information claimed as 
CBI, a copy of the comment that does not contain the information 
claimed as CBI must be submitted for inclusion in the public docket. 
Information so marked will not be disclosed except in accordance with 
procedures set forth in 40 CFR part 2.
    B. Tips for Preparing Your Comments. When submitting comments, 
remember to:
     Identify the rulemaking by docket number and other 
identifying information (subject heading, Federal Register date and 
page number).
     Follow directions--The agency may ask you to respond to 
specific questions or organize comments by referencing a Code of 
Federal Regulations (CFR) part or section number.
     Explain why you agree or disagree; suggest alternatives 
and substitute language for your requested changes.
     Describe any assumptions and provide any technical 
information and/or data that you used.
     If you estimate potential costs or burdens, explain how 
you arrived at your estimate in sufficient detail to allow for it to be 
reproduced.
     Provide specific examples to illustrate your concerns, and 
suggest alternatives.
     Explain your views as clearly as possible, avoiding the 
use of profanity or personal threats.
     Make sure to submit your comments by the comment period 
deadline identified.

IV. Background

    The manufacturer-run, in-use testing program for heavy-duty diesel 
vehicles that are used on the highway was promulgated in June 2005 to 
monitor the emissions performance of the engines used in those vehicles 
when operated under a wide range of real world driving conditions.\1\ 
The program is specifically intended to monitor compliance with the 
applicable Not-to-Exceed (NTE) exhaust emission standards for non-
methane hydrocarbons (NMHC), carbon monoxide (CO), oxides of nitrogen 
(NOX), and particulate matter (PM). It requires each 
manufacturer of heavy-duty highway diesel engines to assess the in-use 
exhaust emissions from their engines using onboard, portable emission 
measurement systems (PEMS) during typical operation while on the road.
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    \1\ See ``Control of Emissions of Air Pollution From New York 
Motor Vehicles: In-Use Testing for Heavy-Duty Diesel Engines and 
Vehicles, 70 FR 34594 (June 14, 2005).''
---------------------------------------------------------------------------

    The in-use testing program begins with a two-year pilot (i.e., 
demonstration) program for gaseous emissions (i.e., NMHC, CO, and 
NOX) in calendar years 2005 and 2006. As originally adopted, 
the program also includes a pilot program for PM emissions in calendar 
years 2006 and 2007. The one-year offset acknowledged that the portable 
measurement system technology for PM emissions was lagging that for 
measuring gaseous emissions. The programs are fully enforceable after 
their respective pilot program ends, i.e., the 2007 calendar year for 
gaseous emissions and the 2008 calendar year for PM emissions. The 
enforceable program applies to 2007 and later model year diesel 
engines. Each manufacturer generally has 18 months to report all 
required test results for the engine families that EPA selects for 
testing in any calendar year.
    For the purposes of the in-use testing program, EPA established a 
vehicle pass/fail criterion for each pollutant that compares a 
vehicle's measured in-use emissions to a corresponding numerical 
compliance limit, i.e., NTE threshold. The NTE threshold for each 
pollutant is the sum of the NTE standard, any in-use compliance testing 
margin that is already allowed by the regulations, and a new emission 
measurement accuracy margin associated with the use of PEMS. The PEMS 
accuracy margin is the difference between the emission measurement 
error for the portable instrument and the measurement error for 
``laboratory grade'' instruments that are used to test vehicles or 
engines on a dynamometer in a laboratory setting. The accuracy 
allowances are expressed in the same numerical terms as the

[[Page 13443]]

applicable NTE emission standards, i.e., grams of pollutant per brake 
horsepower-hour (g/bhp-hr).
    When the in-use testing program was first established in June of 
2005, there was uncertainty regarding what specific accuracy margins 
should be used in the in-use testing program, since the portable 
measurement devices that were expected to be used in the program had 
not been rigorously tested at that time. As a result, we promulgated 
interim accuracy allowances for use in the pilot programs.\2\ These 
interim values were believed to represent an upper bound of the 
possible instrumentation variability based on our experience with 
portable and laboratory instruments and test methods.
    In May of 2005, shortly before the in-use test program was 
promulgated, EPA entered into a memorandum of agreement (MOA) with the 
California Air Resources Board (CARB) and the manufacturers of heavy-
duty highway diesel engines (through the Engine Manufacturers 
Association (EMA)) to develop ``data driven'' emission measurement 
allowances through a comprehensive research, development, and 
demonstration program for the fully enforceable programs, i.e., 
beginning in the 2007 calendar year for gaseous emissions and the 2008 
calendar year for PM.\3\ The overall test program was designed to be 
completed in two phases. The first phase addressed gaseous emission 
accuracy margins and the second phase addressed PM emission accuracy 
margins. The program was to be managed by EPA, in close cooperation 
with CARB and the involved engine manufacturers.
    The MOA also addressed the consequences of failing to complete the 
accuracy margin development work in time for the scheduled start of 
either the gaseous or PM enforceable programs. Two of these provisions 
are most relevant to today's rule. The first provision addresses short 
term delays in receiving the final accuracy margins. Specifically, for 
each month the accuracy margins are delayed beyond the agreed upon 
dates, then affected gaseous emissions or PM enforceable program, i.e., 
either gaseous emissions or PM, would be delayed by the same number of 
months up to three months. The second provision addresses delays in 
excess of three months. In particular, if the accuracy allowances were 
delayed beyond three months of the agreed upon dates, then the affected 
gaseous or PM enforceable program would be placed in abeyance for a 
year and the respective pilot program would be extended to include that 
year using the interim allowance(s).
    Finally, the MOA acknowledged that if fundamental, irresolvable 
technical problems were identified relative to PM PEMS, the PM portion 
of the in-use testing program would be placed into abeyance until such 
time as suitable devices were identified and available, or the problems 
otherwise resolved.

V. Details of the Rule

    This Direct Final Rule establishes new, final gaseous emission 
measurement margins that are required for the manufacturer-run, in-use 
test program for heavy-duty diesel vehicles and engines. This Direct 
Final Rule also makes several changes to the in-use test program in the 
early years of testing. First, it places the fully enforceable PM 
program, which would have begun in 2008, into abeyance for one year due 
to delays in the accuracy margin development program. In its place, the 
pilot program for PM will be extended into 2008. Second, it grants a 
request by EMA and its member companies to place the 2006 PM pilot 
program into abeyance to accommodate their concerns regarding the 
availability and efficacy of PM PEMS. Third, it provides engine 
manufacturers with additional time to conduct in-use testing and report 
the results to EPA because of delays in developing the requisite 
electronic reporting guidance, additional short-term delays in the PM 
accuracy margin development program, and to grant a request from some 
engine manufacturers to delay PM PEMS purchasing decisions until they 
could evaluate the initial results of the PM accuracy margin. That will 
allow them to make more refined purchasing decisions and to have the 
resulting PM PEMS include any instrumentation upgrades that may be 
forthcoming. Fourth, it grants a request from engine manufacturers for 
the flexibility to recruit and test separate vehicles for the 2007 and 
2008 gaseous emissions and PM test programs, and to recruit test 
vehicles from their internal fleets and test them while being operated 
by company employees for the 2007 PM pilot program. This addresses the 
manufacturers' concerns that procuring and instrumenting test vehicles 
with PM PEMS could, in some instances, be more complex and time 
consuming than for gaseous emissions testing. Finally, this rulemaking 
removes references in the applicable regulations to the development of 
final accuracy margins for measuring gaseous emissions with portable 
systems because that program has been completed. Each of these changes 
is further described separately below.

A. Gaseous Emission Measurement Margins for Manufacturer-Run, In-Use 
Testing

1. Results of the Test Program Under the Memorandum of Agreement (MOA)
    The MOA (described in section IV.) called for development of a 
comprehensive test plan for determining the final emission measurement 
accuracy margins for the manufacturer-run, in-use testing program. The 
test plan for the gaseous pollutants was subsequently agreed upon on 
May 20, 2005.\4\ Generally, the detailed plan included a methodology 
that called for: (1) Comprehensive engine testing in the laboratory to 
assess the agreed upon sources of possible error and the resultant 
measurement variability between the PEMS and laboratory instrumentation 
and measurement methods; (2) the effects of environmental conditions on 
PEMS error and the variability in key engine parameters supplied by the 
engine's electronic controls to the PEMS; (3) the development of a 
statistically-based computer model to simulate effects of all sources 
of error on the final measurement accuracy margins; and (4) validation 
of the simulation model results and resulting accuracy margins against 
data generated through actual in-use field testing using simultaneous 
on-vehicle measurements from a mobile emissions laboratory (i.e., 
laboratory-grade instruments mounted inside a trailer) and a PEMS unit. 
This validation step is important because it provides confidence that 
the simulation model results reflect reasonable measurement allowances. 
If the two methods do not statistically agree, then there may be 
possible errors in the simulation model, the in-use mobile emissions 
testing results, or both.
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    \2\ The interim additive accuracy margins for the pilot programs 
are: NMHC = 0.17 g/bhp-hr, NOX = 0.50 g/bhp-hr, CO = 0.60 
g/bhp-hr, and PM = 0.10 g/bhp-hr.
    \3\ See ``Memorandum of Agreement, Program to Develop Emission 
Measurement Accuracy Margins for Heavy-Duty In-Use Testing,'' dated 
May 2005. A copy of the memorandum is available in the public docket 
for this rule and at the EPA/OTAQ Web site (http://www.epa.gov/otaq/
hd-hwy.htm).
    \4\ See ``Test Plan to Determine PEMS Measurement Allowances for 
the Gaseous Emissions Regulated Under the Manufacturer-Run Heavy-
Duty Diesel In-Use Testing Program,'' for the U.S. Environmental 
Protection Agency, California Air Resources Board, and Engine 
Manufacturers Association, dated May 20, 2005. A copy of the report 
is available in the public docket for this rule and at the EPA/OTAQ 
Web site (http://www.epa.gov/otaq/hd-hwy.htm).
---------------------------------------------------------------------------

    The test plan also contained the statistically-based algorithms for 
calculating the data-driven margins for

[[Page 13444]]

the gaseous pollutants in addition to three different brake-specific 
calculation methods for determining emission results (i.e., grams/bhp-
hr) from in-use data. The first two of these methods (Methods 1 and 2 
below) are described in 40 CFR 1065.650(a)(1) and (3). The third method 
has been suggested by the engine manufacturers and would require prior 
approval of the Administrator before it could be used as provided for 
in 40 CFR 1065.915(d)(5)(iv). The basic calculation is similar for each 
of the three methods and is shown generically in the following 
---------------------------------------------------------------------------
equation:

Brake-Specific Emissions = Mass of Pollutant/Work Performed

Where:
    Mass of Pollutant = Exhaust Pollutant Concentration x Exhaust 
Flow Rate

    The three methods differ primarily in how the exhaust flow rate or 
the work portion (i.e., brake horsepower-hours) of the calculation is 
determined. The methods are also more fully described in the test plan.
    After the simulation modeling results for the three calculation 
methods were completed, the test plan called for the final set of 
accuracy margins (i.e., NMHC, CO, and NOX) to be determined 
by the following generalized process. First, identify the maximum 
percentage measurement error associated with any of the three 
pollutants, i.e., without regard to the pollutant species, for each of 
the three calculation methods.\5\ Second, from these three maximum 
values, select the method with the lowest or minimum value. Third, and 
finally, use the results from that method to determine the measurement 
accuracy margins for all of the pollutants.
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    \5\ The percentage error for each pollutant and calculation 
method was found by dividing the associated numerical result from 
the simulation model by an NTE limit. EPA determined the NTE limit 
by multiplying an assumed in-use emission rate from future heavy-
duty diesel engines in the 2010 model year timeframe by the 
multiplier that is used to calculate the NTE standard. In this case 
the multiplier is 1.5. See 40 CFR 86.007-11(a)(4) for more 
information on the NTE multiplier.
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    The cooperative test program for gaseous pollutants as described in 
the MOA was completed and a final report issued.\6\ \7\ When the 
predicted results from the model simulations were compared to the 
mobile emissions laboratory results, only Method 1 could be validated 
for NMHC and NOX. Methods 2 and 3 could only be validated 
for NMHC. None of the methods validated for CO. While unexpected, the 
lack of overall validation for the three methods is not necessarily 
surprising given the enormous amount of laboratory-based and on-vehicle 
testing, the number of possible errors and the model simulations (i.e., 
thousands of simulation runs), and complexity of the overall 
cooperative test program.
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    \6\ See ``Gaseous Emission Measurement Accuracy Margins for 
Portable Emission Measurement Systems Used in the Heavy-Duty Diesel 
Engine In-Use Testing Program: Revised Final Report,'' U.S. 
Environmental Protection Agency, February 2008, EPA report number: 
EPA420-R-08-005. A copy of the report is available in the public 
docket for this rule and at the EPA/OTAQ Web site (http://
www.epa.gov/otaq/hd-hwy.htm).
    \7\ The estimated cost of the gaseous emission measurement 
accuracy margin test program is $2.2 million.
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    The emission test data, simulation model, and in-use validation 
data were investigated further to determine if there were any errors 
that could be remedied to resolve the validation problems. While this 
investigation identified some reasons for the lack of validation and 
potential additional work that might lead to fully validated results, 
none of additional work was judged to be possible under the schedule 
for determining the final set of gaseous emission accuracy allowances 
as required by the MOA.
    In order to ensure that the fully enforceable program for gaseous 
emissions started on schedule and to provide an orderly transition for 
engines designed and produced during the early years of the program, 
the emission measurement accuracy margins from Method 1 were chosen for 
use in the fully enforceable program for 2007 through 2009 model year 
engine families regardless of the calendar year in which they may be 
selected for testing.\8\ Therefore, the accuracy margins based on the 
completed test program only apply to the emission results calculated 
using Method 1 for these initial three model years.\9\ The resultant 
emission measurement accuracy margins are: 0.02 for NMHC; 0.5 for CO; 
and 0.45 for NOX.
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    \8\ Method 1 was chosen because it was the only method that was 
validated for the two most environmentally important pollutants from 
heavy-duty diesel truck engines, i.e., NMHC and NOX.
    \9\ The test program results led to no accuracy allowances for 
either of the other two calculation methods from 2007 through 2009 
model year engine families.
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    At the time Method 1 was selected, it was anticipated that EPA 
would continue to develop validated results for the remaining methods, 
although it was unknown how long that work might take. It was also 
anticipated that if the work was successful, new accuracy margins could 
be established through rulemaking, although the above accuracy margins 
for Method 1 would be retained for 2007 through 2009 model year engine 
families, as described above.
2. Results of Additional Gaseous Measurement Margin Analysis
    At the end of the cooperative test program that eventually led to 
using the accuracy margins for Method 1 testing for 2007 through 2009 
model year engine families, EPA expressed its intent to continue work 
to develop more robust gaseous emission measurement accuracy margins, 
especially for NOX, as originally anticipated in the test 
program plan. We envisioned this work would primarily focus on the 
reasons for the lack of validation and potential additional work that 
was identified at the end of the original test program, as previously 
discussed.
    In our follow-on work we corrected an error in the previous test 
data, included additional valid engine test data that was not used in 
the original work, and eliminated or corrected some error biases or 
data outliers in the data set based on engineering judgment. A total of 
four different modified data sets or scenarios were constructed for 
combinations of the changes described above for each of the three 
calculation methods.\10\ After rerunning the simulation model for the 
various combinations, we found that each of the four modifications 
validated for all three methods and all the gaseous pollutants. 
Furthermore, we found that the results from the various methods for 
each pollutant were numerically quite close to each other.
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    \10\ See ``Additional Analyses of the Monte Carlo Model 
Developed for the Determination of PEMS Measurement Allowances for 
Gaseous Emissions Regulated Under the Heavy-Duty Diesel Engine In-
Use Testing Program,'' August 2007, EPA report number: EPA420-R-07-
010. A copy of the report is available in the public docket for this 
rule and at the EPA/OTAQ Web site (http://www.epa.gov/otaq/hd-
hwy.htm).
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    In order to select final accuracy margins from the validated 
results described above, we evaluated each of the modified data sets to 
identify the most appropriate and reasonable revision from an 
engineering science perspective (or based on good engineering 
practice). Based on this evaluation, we selected the modification 
scenario where some data from three test points (emission results at 
specific engine speed and load combinations) from one of the test 
engines were excluded from the data set. These data reflected 
atypically elevated levels of NOX with large and 
inconsistent measurement errors. The other modification scenarios, 
while justifiable, were judged to represent somewhat more extreme or 
difficult to

[[Page 13445]]

defend manipulations of the data on a relative basis.
    After selecting the most appropriate modified data set, we 
determined the final accuracy margins by applying the ``minimum of the 
maximums'' selection criteria from the original test plan to the three 
calculation methods. This showed that the largest percentage errors 
were associated with NOX and that Method 2 had the lowest 
error for that pollutant of the three methods.\11\ Therefore, pursuant 
to the results of the original test plan, the subsequent validation 
work performed by EPA, and after discussions with the other parties to 
the MOA, we are promulgating the final emission measurement accuracy 
margins shown in Table 1 for all the calculation methodologies 
beginning with 2010 model year engine families. Also as shown in the 
table, we are adopting these same numerical values for Methods 2 and 3 
for 2007 through 2009 model year engines, at the discretion of the 
engine manufacturers, in order to provide a full compliment of 
calculation methods and accuracy margins for those engines.
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    \11\ ``Selection of Final Gaseous Emission Measurement Accuracy 
Margins for Portable Emission Measurement Systems,'' memorandum from 
Richard S. Wilcox, U.S. Environmental Protection Agency, to Docket 
No. EPA-HQ-OAR-2004-0072, dated November 4, 2007. A copy of the 
document is available in the public docket for this rule.

    Table 1.--Final Measurement Accuracy Margins for the Enforceable Gaseous Emissions In-Use Testing Program
----------------------------------------------------------------------------------------------------------------
                                                                       Accuracy margins (g/bhp-hr)
                                                       ---------------------------------------------------------
                                                             2007-2009 model year engines        2010 and later
                       Pollutant                       ---------------------------------------     model year
                                                                                                    engines
                                                           Method 1 only     Methods 2 and 3  ------------------
                                                                                                  All methods
----------------------------------------------------------------------------------------------------------------
NMHC..................................................                0.02               0.01               0.01
CO....................................................                0.5                0.25               0.25
NOX...................................................                0.45               0.15               0.15
----------------------------------------------------------------------------------------------------------------

B. NMHC Plus NOX In-Use Testing Accuracy Margins

    The June 2005 final rule that implemented the in-use testing 
program addressed accuracy margins for each of the gaseous pollutants 
and their associated individual standards, i.e., NMHC, CO, and 
NOX. The MOA and subsequent gaseous emissions test program 
also focused on identifying the final accuracy margins for these 
individual pollutants. In developing the original rule and subsequent 
test program, however, we failed to recognize that 2004 through 2006 
model year diesel engine families may be certified to a combined 
NOX plus NMHC standard under Sec.  86.004-11(a)(1) of the 
applicable regulations. Furthermore, under the ``phase-in options'' of 
Sec.  86.007-11(g)(1) an engine manufacturer may optionally certify 
some of its production in model years 2007 through 2009 to the combined 
NOX plus NMHC standard for 2006 model year engines under 
Sec.  86.2004-11, rather than the otherwise applicable individual 
NOX and NMHC standards. Therefore, we are correcting this 
oversight by promulgating in-use testing accuracy margins for 2004-2009 
model year engines that may be certified to the combined NOX 
plus NMHC standard.
    The methodology for determining an accuracy margin for the combined 
NOX plus NMHC emission standard is the same as that used to 
determine the numerical value of the combined standard itself. 
Specifically, the individual NOX and NMHC accuracy margins 
are simply added together to provide a single value. Therefore, for 
2004-2007 model year engines that may be tested under the gaseous 
emission pilot program for the 2006 and 2007 calendar years, the 
combined accuracy margin is the sum of the individual NOX 
and NMHC values already contained in Sec.  86.1912, or 0.67 g/bhp-hr. 
For engines tested in the enforceable program that begins in the 2007 
calendar year and applies to 2007 and later model year diesel engines, 
the combined NOX plus NMHC accuracy margins, using the 
individual values from Table 1, are shown in Table 2.

 Table 2.--Final Combined NOX Plus NMHC Measurement Accuracy Margins for
        the Enforceable Gaseous Emissions In-Use Testing Program
------------------------------------------------------------------------
                                   Accuracy margins for 2007-2009 model
                                         year engines  (g/bhp-hr)
            Pollutant            ---------------------------------------
                                     Method 1 only      Methods 2 and 3
------------------------------------------------------------------------
NOX + NMHC......................               0.47                0.16
------------------------------------------------------------------------

C. Delaying the Enforceable PM Program From 2008 to 2009

    The MOA described in section IV. acknowledged that in order to 
promulgate new measurement accuracy margins with adequate lead time to 
begin the 2008 enforceable PM program, certain key milestone dates in 
the test program had to be achieved. For example, all the parties 
agreed that the final accuracy margins and documentation were needed by 
November 1, 2007. That meant the final test plan would have to be 
agreed upon by September 2006, given the time needed to complete the 
testing and analysis. Contingencies for missing the final delivery date 
were specified in the MOA and in the June 2005 final rulemaking.\12\ 
Most relevant to this action was that if the final values and

[[Page 13446]]

documentation were delayed more than three months from November 1, 
2007, then the PM pilot program would continue for calendar year 2008 
in place of the fully enforceable program for that year.
---------------------------------------------------------------------------

    \12\ See 40 CFR 86.1935.
---------------------------------------------------------------------------

    Completing the PM test program on schedule required that the 
initial work be conducted in parallel with the ongoing gaseous emission 
test program using the same contractors and personnel from EPA, CARB, 
and the engine manufacturers. Due to unexpected issues in the gaseous 
emission test program and the lack of other resources, all work on the 
PM test plan and subsequent test program had to be postponed. The end 
result of this postponement is that the final accuracy margin for PM 
will be delayed by approximately one year. Accordingly, the MOA and in-
use test program regulations require that the first year of the 
previously adopted enforceable program (calendar year 2008) be placed 
into abeyance and the PM pilot program continued for that year. Hence, 
the enforceable PM program will now begin in 2009 calendar year.
    In isolation, delaying the start of the enforceable PM program by 
one year and continuing the PM pilot program for that year would result 
in a three-year pilot, i.e., 2006 through 2008, as described above. 
However, as explained in the next section, we also believe it is 
appropriate to eliminate the first year of the original two-year pilot 
program. As a result, a two-year PM pilot will still occur as 
originally envisioned beginning with the 2007 calendar year.

D. Suspending the 2006 PM Pilot Program

    The in-use testing program, as originally adopted in June 2005, 
included a two-year pilot (i.e., demonstration) program for PM 
emissions in calendar years 2006 and 2007. In establishing this 
requirement, EPA noted that the onboard measurement of PM emissions was 
significantly more challenging than for gaseous emissions, and that 
further development of the requisite portable measurement systems would 
be needed. We also stated that our technical assessment indicated that 
these systems would be available in time to start the in-use testing 
program. More specifically with regard to the PM pilot program, we 
noted our expectation that engine manufacturers would use ``best 
available'' prototype systems that were capable of measuring these 
emissions as required. Nonetheless, in recognition of the then 
remaining technical uncertainties, we added a provision to the 
regulations that would suspend the in-use test program as it applied to 
PM measurement if we discovered fundamental technical problems with 
portable in-use PM measurement systems that could not be resolvable in 
a reasonable time.
    In a letter dated January 4, 2007, EMA requested that the first 
year of the two-year PM pilot program be held in abeyance.\13\ The 
principle reasons were summarized as follows: (1) Suitable portable 
measurement systems are not commercially available; (2) fundamental 
technical issues remain to be resolved; (3) the joint program to 
develop a data-driven PM accuracy margin for these devices has been 
delayed at least one year; and (4) the final in-use testing regulation 
and the MOA require the one-year delay. The third issue relates to the 
delay of the first year of the fully enforceable PM test program from 
2008 until 2009 as discussed in the previous section. The last issue 
relates to regulatory requirement to delay the PM measurement program 
if fundamental technical problems were discovered as described in the 
preceding paragraph.
---------------------------------------------------------------------------

    \13\ See letter from Timothy A. French, Engine Manufacturers 
Association, to Khesha Jennings, U.S. Environmental Protection 
Agency, dated January 4, 2007. A copy of the letter is available in 
the public docket for this rule.
---------------------------------------------------------------------------

    Focusing on the first two points, we reminded EMA at the time that 
although some parties may interpret the term ``commercially available'' 
differently, the original rulemaking clearly stated the expectation 
that prototype portable measurement systems would be used in the PM 
pilot program if they could accurately and reliably measure PM 
emissions. This was acceptable because the pilot is designed for the 
engine manufacturers and EPA to gain experience in implementing the in-
use testing program and using the portable measurement systems. Also, 
we noted that both EPA and some engine manufacturers had already 
purchased prototype portable PM measurement systems meeting these 
requirements. Finally, we described how we had successfully used the 
same prototype system to measure PM emissions over NTE events while 
traveling cross-country in a particulate trap-equipped truck using 
ultra-low sulfur diesel fuel.\14\ Therefore, we concluded that 
acceptable measurement systems were available and no fundamental, 
irresolvable issues had been identified that would justify a delay in 
the pilot program. Nonetheless, we invited EMA to further elaborate on 
their technical concerns with the currently available measurement 
systems.
---------------------------------------------------------------------------

    \14\ ``Road Test of an On-board Particulate Matter Mass 
Measurement System,'' D. R. Booker, Sensors, Inc., R. A. Giannelli 
and J. Hu, U.S. Environmental Protection Agency, March 2007, SAE 
paper number 2007-01-1116.
---------------------------------------------------------------------------

    In a subsequent letter dated April 11, 2007, EMA more specifically 
detailed its technical concerns with currently available portable PM 
measurement systems.\15\ Specifically, EMA listed fourteen technical 
considerations. These generally can be summarized as follows: (1) The 
devices had not been demonstrated as meeting the technical requirements 
of EPA's 40 CFR 1065; (2) the engine manufacturers' have no current 
experience with the measurement device because the current version is 
relatively new, the instrument manufacturer does not offer all the 
accessories needed to install and operate the system; (3) mounting the 
units on some trucks presents installation issues; (4) the sampling 
technology will not work properly with dirtier pre-2007 engines; (5) no 
training from the instrument manufacturer was available; and (6) a 
number of issues with accuracy and repeatability remain to be resolved. 
They also argued that it would be better to take the time now to focus 
on developing better portable PM measurement devices and, thereby, 
helping to ensure a successful launch of the fully enforceable program 
in 2009, especially since we would still have a full two years of the 
PM pilot program as originally called for by the regulations.
---------------------------------------------------------------------------

    \15\ See letter from Timothy A. French, Engine Manufacturers 
Association, to Khesha Jennings, U.S. Environmental Protection 
Agency, dated April 11, 2007. A copy of the letter is available in 
the public docket for this rule.
---------------------------------------------------------------------------

    After carefully considering EMA's more explicit concerns, we 
concluded that: (1) A number of the issues were only relevant to the 
future fully enforceable program, not the pilot demonstration program; 
(2) EPA and EMA could work to resolve some issues such as only testing 
existing or prototype lower emitting buses or trucks; and (3) the 
remaining items simply did not by themselves reach a level that would 
justify delaying the pilot program. At the same time, we agreed with 
EMA that it is more important to continue to work cooperatively for a 
successful launch of the enforceable PM in-use testing program, 
especially since we will still have a two-year pilot. Therefore, at 
that point in time, we decided it was in the best interests of all 
parties to eliminate the 2006 calendar year pilot program and focus our 
collective efforts to improve the current portable PM measurement 
systems and conduct the cooperative research and development program 
for this pollutant.

[[Page 13447]]

E. Revised Schedules and Testing Flexibilities for the 2005 Through 
2009 In-Use Test Programs

    The June 2005 final rule that established the heavy-duty in-use 
test program stated that EPA would typically select engine families for 
testing in June of each calendar year. Further, the regulations allowed 
18 months from the time engine families were designated for engine 
manufacturers to complete all testing and report the results to EPA. 
Subsequent to the final rule, we found that certain adjustments to the 
test schedules were necessary in the early years of the program for the 
reasons given below. The adjustments for engine family designation and 
reporting dates are summarized in Table 3.

                       Table 3.--Revised Engine Family Designation and Reporting Schedules
----------------------------------------------------------------------------------------------------------------
                                              Designate families                         Report due
              Program              -----------------------------------------------------------------------------
                                       Original            Revised            Original            Revised
----------------------------------------------------------------------------------------------------------------
2005 Gaseous Pilot *..............         06/2005  Unchanged............         11/2006  11/2007.
2006 Gaseous Pilot................         06/2006  12/2006..............         11/2007  11/2008.
2007 Gaseous Enforceable..........         06/2007  12/2007..............         11/2008  11/2009.
2007 PM Pilot.....................         06/2007  12/2007..............         11/2008  05/2010.
2008 Gaseous Enforceable..........         06/2008  09/2008..............         11/2009  03/2010.
2008 PM Pilot.....................         06/2008  09/2008..............         11/2009  09/2010.
2009 Gaseous Enforceable..........         06/2009  Unchanged............         11/2010  04/2011.
2009 PM Enforceable...............         06/2009  Unchanged............         11/2010  04/2011.
2010 Gaseous Enforceable **.......         06/2010  Unchanged............         11/2011  Unchanged.
2010 PM Enforceable **............         06/2010  Unchanged............         11/2011  Unchanged.
----------------------------------------------------------------------------------------------------------------
* The 2005 Gaseous Pilot Program has been completed.
** For illustration only. The 2010 program dates are as originally promulgated.

    When the final rule was promulgated, EPA was working with ARB and 
the engine manufacturers to create a standardized, electronic reporting 
format which precisely specified each of the numerous reporting data 
elements and enabled the test results from the portable emission 
measurement systems to be reported into EPA's computerized database. We 
had envisioned that this work would be completed in a timely manner so 
that the 2005 gaseous emissions pilot program could be conducted as 
scheduled. However, despite the diligent work of all parties, creating 
the electronic reporting guidance for this all new test program proved 
more complex and time consuming than expected. By September 2005 it 
became obvious that the lack of the reporting guidance document had 
become an impediment to efficiently conducting the in-use test program. 
As a result, EPA agreed with the engine manufacturers, and ARB 
concurred, that the start of the 18-month reporting period should be 
delayed until a reporting guidance document was issued.\16\
---------------------------------------------------------------------------

    \16\ See letter from Merrylin Zaw-Mon, U.S. Environmental 
Protection Agency, to John Duerr, Detroit Diesel Corporation, dated 
November 15, 2005. A copy of the letter is available in the public 
docket for this rule.
---------------------------------------------------------------------------

    In late May 2006 the reporting guidance was released and the 18-
month reporting period began in June of that year and ended in November 
2007.\17\ To accommodate this delay without unduly compressing or 
overlapping the testing in subsequent years, we are delaying engine 
family designations, and sometimes extending the reporting period, for 
the 2006 through 2008 gaseous emissions testing programs. Specifically 
as shown in Table 3, we are delaying engine family designations for 
2006 until December of that year and extending the reporting period to 
24 months. For 2007, we are similarly delaying engine family 
designations and extending the reporting period. Further, we are 
shortening the delay in selecting engine families for the 2008 gaseous 
emissions enforceable program to four months, i.e., September of that 
year, and subsequently returning to the normal 18-month reporting 
period. Finally, we are aligning the engine family designation dates 
for the 2007 and 2008 PM pilot programs with the revised gaseous 
emissions program dates to keep the program start dates the same.
---------------------------------------------------------------------------

    \17\ All manufacturers successfully reported the 2005 gaseous 
emission test results according to that modified schedule.
---------------------------------------------------------------------------

    We have more recently reevaluated the schedules for the in-use PM 
test program. Our reassessment was based on the progress that is being 
made to develop ``data driven'' emission measurement allowances as part 
of the comprehensive research, development, and demonstration program 
outlined in the MOA,\18\ as previously described in section IV. The 
reassessment was also made in the context that successfully measuring 
PM emissions onboard a vehicle and deploying this technology in revenue 
service represents the fundamental next step in emission measurement 
technology and environmental protection. On balance, we have concluded 
that additional time and added flexibility in the early years of the 
in-use PM test program is required now to help ensure that this 
important programmatic advancement is successful.
---------------------------------------------------------------------------

    \18\ See ``Memorandum of Agreement, Program to Develop Emission 
Measurement Accuracy Margins for Heavy-Duty In-Use Testing,'' dated 
May 2005. A copy of the memorandum is available in the public docket 
for this rule and at the EPA/OTAQ Web site (http://www.epa.gov/otaq/
hd-hwy.htm).
---------------------------------------------------------------------------

    More specifically, last summer EPA and the other contributors to 
the PM accuracy margin development program decided to do some pre-
testing of a PM PEMS prior to initiating the full test program in order 
to further demonstrate and refine the test protocol and 
instrumentation. This led to some technical changes to the PM PEMS 
themselves. It also caused the full accuracy margin development program 
to be delayed. At nearly the same time, some engine manufacturers 
stated that they would like to use the initial results from the full 
test program on the various PM PEMS devices in order to make more 
refined purchasing decisions and to include any resulting upgrades to 
the instruments. Given the importance of the program and expense 
involved, we believe it is reasonable to accommodate the delay in 
initiating the full PM accuracy margin development program and to allow 
manufacturers to use the initial test results for purchasing decisions. 
Therefore, as shown in Table 3, we are adding a total of six months to 
the testing period to the 2007 PM pilot program. As with the gaseous 
emissions program described above, we are also extending the PM 
reporting

[[Page 13448]]

periods for the 2008 pilot and the 2009 enforceable PM programs to 
avoid compression effects. Further, we are extending the reporting 
period for the 2009 enforceable gaseous emissions program to match the 
revised period for the 2009 enforceable PM program to couple and 
realign the programs as originally intended. Finally, we want to make 
it clear that any month-to-month delay (up to three months) in 
initiating the 2009 enforceable PM program, as outlined in the accuracy 
margin development MOA \19\ and described in section IV, will have no 
effect on the reporting dates described above, i.e., no additional 
time.
---------------------------------------------------------------------------

    \19\ See ``Memorandum of Agreement, Program to Develop Emission 
Measurement Accuracy Margins for Heavy-Duty In-Use Testing,'' dated 
May 2005. A copy of the memorandum is available in the public docket 
for this rule and at the EPA/OTAQ Web site (http://www.epa.gov/otaq/
hd-hwy.htm).
---------------------------------------------------------------------------

    Most recently engine manufacturers have expressed concerns that 
procuring and instrumenting test vehicles with PM PEMS could, in some 
instances, be more complex and time consuming than for gaseous 
emissions testing. For example, they claim that mounting the 
instruments and running sampling lines with current generation PM PEMS 
might require drilling holes in a truck's cab or creating special 
mounting hardware. In such cases, the manufacturers argue that it might 
be difficult to obtain vehicles from independent owners as required by 
the current regulations. Engine manufacturers have requested that they 
be given the flexibility to recruit and test vehicles from their 
captive fleets for the 2007 PM pilot program based on these concerns. 
In considering the engine manufacturers appeal, we note that the 
gaseous emissions enforceable and PM pilot programs for that year would 
have to be ``decoupled'' so that the gaseous emissions program would 
continue to be conducted according to the applicable testing protocols, 
e.g., obtaining vehicles from independent owners and testing them in 
normal revenue service.
    While we are not convinced that current PM PEMS will cause these 
unique challenges, we also can not conclusively rule out some 
instrumentation and recruiting issues in the early part of the PM 
program. Again, given the importance of successfully launching this 
program, EPA is granting the engine manufacturers' request to modify 
the PM pilot program test protocols. Therefore, we are allowing 
manufacturers to recruit vehicles from their captive fleet and to test 
them while being driven by a company employee. However, manufacturers 
must ensure that the vehicles are screened, prepared, operated, and 
tested in accordance with all other applicable requirements. 
Furthermore, the vehicle must be tested by being driven on a route that 
reasonably replicates normal, in-use revenue service for that type of 
vehicle. The requirements for the enforceable gaseous emissions test 
program for 2007 and 2008 are unchanged.

F. Removing the Gaseous Accuracy Test Program From the Regulations

    We are taking this opportunity to delete the references in Sec.  
86.1935 that pertain to the final report for gaseous emission accuracy 
margins and the consequences that would ensue if the report was delayed 
beyond certain dates. These provisions are no longer needed because 
accuracy margins for gaseous pollutants are being promulgated in this 
Direct Final Rule. The revised section, therefore, appropriately 
focuses on the ongoing development of accuracy margins for PM 
emissions.

VI. Statutory and Executive Order Reviews

A. Executive Order 12866: Regulatory Planning and Review

    This action is not a ``significant regulatory action'' under the 
terms of Executive Order (EO) 12866 (58 FR 51735, October 4, 1993) and 
is therefore not subject to review under the EO. This Direct Final Rule 
merely replaces the interim gaseous emission measurement accuracy 
allowances for portable emission measurement systems with final values 
and delays the in-use testing implementation dates for the fully 
enforceable PM test program as either envisioned or allowed for in the 
original final rule. This rule also grants a request from the affected 
engine manufacturers for a one year delay in the start of the pilot 
testing program for PM. Further, there are no costs associated with 
this rule beyond those envisioned in the original rule.

B. Paperwork Reduction Act

    This direct final rule does not include any new collection 
requirements, as it acts to replace interim gaseous emission 
measurement accuracy allowances for portable emission measurement 
systems with final values and delays the implementation schedule for 
the in-use PM testing program. Therefore, there are no new paperwork 
requirements associated with this rule.
    Burden means the total time, effort, or financial resources 
expended by persons to generate, maintain, retain, or disclose or 
provide information to or for a Federal agency. This includes the time 
needed to review instructions; develop, acquire, install, and utilize 
technology and systems for the purposes of collecting, validating, and 
verifying information, processing and maintaining information, and 
disclosing and providing information; adjust the existing ways to 
comply with any previously applicable instructions and requirements; 
train personnel to be able to respond to a collection of information; 
search data sources; complete and review the collection of information; 
and transmit or otherwise disclose the information.
    An agency may not conduct or sponsor, and a person is not required 
to respond to a collection of information unless it displays a 
currently valid OMB control number. The OMB control numbers for EPA's 
regulations in 40 CFR are listed in 40 CFR part 9.

C. Regulatory Flexibility Act

    EPA has determined that it is not necessary to prepare a regulatory 
flexibility analysis in connection with this direct final rule.
    For purposes of assessing the impacts of this final rule on small 
entities, a small entity is defined as: (1) A small business that meets 
the definition for business based on SBA size standards at 13 CFR 
121.201; (2) a small governmental jurisdiction that is a government of 
a city, county, town, school district or special district with a 
population of less than 50,000; and (3) a small organization that is 
any not-for-profit enterprise which is independently owned and operated 
and is not dominant in its field.
    After considering the economic impacts of today's final rule on 
small entities, EPA has concluded that this action will not have a 
significant economic impact on a substantial number of small entities. 
In determining whether a rule has a significant economic impact on a 
substantial number of small entities, the impact of concern is any 
significant adverse economic impact on small entities, since the 
primary purpose of the regulatory flexibility analyses is to identify 
and address regulatory alternatives ``which minimize any significant 
economic impact of the proposed rule on small entities.'' 5 U.S.C. 603 
and 604. Thus, an agency may conclude that a rule will not have a 
significant economic impact on a substantial number of small entities 
if the rule relieves regulatory burden, or otherwise has a positive 
economic effect on all of the small entities subject to the rule.
    This direct final rule acts to replace interim gaseous emission 
measurement

[[Page 13449]]

accuracy allowances for portable emission measurement systems with 
final values and delays the implementation schedule for the in-use PM 
testing program. We have, therefore, concluded that today's final rule 
will relieve regulatory burden for all small entities and will not have 
a significant economic impact on a substantial number of small 
entities.

D. Unfunded Mandates Reform Act

    Title II of the Unfunded Mandates Reform Act of 1995 (UMRA), Public 
Law 104-4, establishes requirements for federal agencies to assess the 
effects of their regulatory actions on state, local, and tribal 
governments and the private sector. Under section 202 of the UMRA, EPA 
generally must prepare a written statement, including a cost-benefit 
analysis, for proposed and final rules with ``federal mandates'' that 
may result in expenditures to state, local, and tribal governments, in 
the aggregate, or to the private sector, of $100 million or more in any 
one year. Before promulgating an EPA rule for which a written statement 
is needed, section 205 of the UMRA generally requires EPA to identify 
and consider a reasonable number of regulatory alternatives and adopt 
the least costly, most cost-effective, or least burdensome alternative 
that achieves the objectives of the rule. The provisions of section 205 
do not apply when they are inconsistent with applicable law. Moreover, 
section 205 allows EPA to adopt an alternative other than the least 
costly, most cost-effective, or least burdensome alternative if the 
Administrator publishes with the final rule an explanation of why such 
an alternative was adopted.
    Before EPA establishes any regulatory requirements that may 
significantly or uniquely affect small governments, including tribal 
governments, it must have developed under section 203 of the UMRA a 
small government agency plan. The plan must provide for notifying 
potentially affected small governments, enabling officials of affected 
small governments to have meaningful and timely input in the 
development of EPA regulatory proposals with significant federal 
intergovernmental mandates, and informing, educating, and advising 
small governments on compliance with the regulatory requirements.
    This rule contains no federal mandates for state, local, or tribal 
governments as defined by the provisions of Title II of the UMRA. The 
rule imposes no enforceable duties on any of these governmental 
entities. Nothing in the rule would significantly or uniquely affect 
small governments. EPA has determined that this rule contains no 
federal mandates that may result in expenditures of more than $100 
million to the private sector in any single year. This direct final 
rule acts to replace interim gaseous emission measurement accuracy 
allowances for portable emission measurement systems with final values 
and delays the implementation schedule for the in-use PM testing 
program. The requirements of UMRA, therefore, do not apply to this 
action.

E. Executive Order 13132: Federalism

    Executive Order 13132, entitled ``Federalism'' (64 FR 43255, August 
10, 1999), requires EPA to develop an accountable process to ensure 
``meaningful and timely input by State and local officials in the 
development of regulatory policies that have federalism implications.'' 
``Policies that have federalism implications'' are defined in the 
Executive Order to include regulations that have ``substantial direct 
effects on the States, on the relationship between the national 
government and the States, or on the distribution of power and 
responsibilities among the various levels of government.''
    Under section 6 of Executive Order 13132, EPA may not issue a 
regulation that has federalism implications, that imposes substantial 
direct compliance costs, and that is not required by statute, unless 
the Federal government provides the funds necessary to pay the direct 
compliance costs incurred by State and local governments, or EPA 
consults with State and local officials early in the process of 
developing the regulation. EPA also may not issue a regulation that has 
federalism implications and that preempts State law, unless the Agency 
consults with State and local officials early in the process of 
developing the regulation.
    Section 4 of the Executive Order contains additional requirements 
for rules that preempt State or local law, even if those rules do not 
have federalism implications (i.e., the rules will not have substantial 
direct effects on the States, on the relationship between the national 
government and the states, or on the distribution of power and 
responsibilities among the various levels of government). Those 
requirements include providing all affected State and local officials 
notice and an opportunity for appropriate participation in the 
development of the regulation. If the preemption is not based on 
express or implied statutory authority, EPA also must consult, to the 
extent practicable, with appropriate State and local officials 
regarding the conflict between State law and Federally protected 
interests within the agency's area of regulatory responsibility.
    This rule does not have federalism implications. It will not have 
substantial direct effects on the States, on the relationship between 
the national government and the States, or on the distribution of power 
and responsibilities among the various levels of government, as 
specified in Executive Order 13132. This direct final rule merely 
replaces interim gaseous emission measurement accuracy allowances for 
portable emission measurement systems with final values and delays the 
implementation schedule for the in-use PM testing program.

F. Executive Order 13175: Consultation and Coordination With Indian 
Tribal Governments

    Executive Order 13175, entitled ``Consultation and Coordination 
With Indian Tribal Governments'' (59 FR 22951, November 6, 2000), 
requires EPA to develop an accountable process to ensure ``meaningful 
and timely input by tribal officials in the development of regulatory 
policies that have tribal implications.'' ``Policies that have tribal 
implications'' is defined in the Executive Order to include regulations 
that have ``substantial direct effects on one or more Indian tribes, on 
the relationship between the Federal government and the Indian tribes, 
or on the distribution of power and responsibilities between the 
Federal government and Indian tribes.''
    This rule does not have tribal implications. It will not have 
substantial direct effects on tribal governments, on the relationship 
between the Federal government and Indian tribes, or on the 
distribution of power and responsibilities between the Federal 
government and Indian tribes, as specified in Executive Order 13175. 
This rule does not uniquely affect the communities of Indian Tribal 
Governments. Further, no circumstances specific to such communities 
exist that would cause an impact on these communities beyond those 
discussed in the other sections of this rule. This direct final rule 
merely replaces interim gaseous emission measurement accuracy 
allowances for portable emission measurement systems with final values 
and delays the implementation schedule for the in-use PM testing 
program. Thus, Executive Order 13175 does not apply to this rule.

G. Executive Order 13045: Protection of Children From Environmental 
Health and Safety Risks

    Executive Order 13045, ``Protection of Children From Environmental 
Health

[[Page 13450]]

Risks and Safety Risks'' (62 FR 19885, April 23, 1997) applies to any 
rule that (1) is determined to be ``economically significant'' as 
defined under Executive Order 12866, and (2) concerns an environmental 
health or safety risk that EPA has reason to believe may have a 
disproportionate effect on children. If the regulatory action meets 
both criteria, section 5-501 of the Order directs the Agency to 
evaluate the environmental health or safety effects of the planned rule 
on children, and explain why the planned regulation is preferable to 
other potentially effective and reasonably feasible alternatives 
considered by the Agency.
    This rule is not subject to the Executive Order because it is not 
economically significant as defined in EO 12866, and because the Agency 
does not have reason to believe the environmental health or safety 
risks addressed by this action present a disproportionate risk to 
children. This direct final rule merely replaces the interim gaseous 
emission measurement accuracy allowances for portable emission 
measurement systems with final values and delays the implementation 
schedule for the in-use PM testing program.

H. Executive Order 13211: Actions That Significantly Affect Energy 
Supply, Distribution, or Use

    This rule is not a ``significant energy action'' as defined in 
Executive Order 13211, ``Actions Concerning Regulations That 
Significantly Affect Energy Supply, Distribution, or Use'' (66 FR 
28355, May 22, 2001) because it is not likely to have a significant 
adverse effect on the supply, distribution or use of energy. This 
direct final rule merely replaces the interim gaseous emission 
measurement accuracy allowances for portable emission measurement 
systems with final values and delays the implementation schedule for 
the in-use PM testing program.

I. National Technology Transfer and Advancement Act

    Section 12(d) of the National Technology Transfer and Advancement 
Act of 1995 (``NTTAA''), Public Law 104-113, section 12(d) (15 U.S.C. 
272 note) directs EPA to use voluntary consensus standards in its 
regulatory activities unless doing so would be inconsistent with 
applicable law or otherwise impractical. Voluntary consensus standards 
are technical standards (such as materials specifications, test 
methods, sampling procedures, and business practices) that are 
developed or adopted by voluntary consensus standards bodies. NTTAA 
directs EPA to provide Congress, through OMB, explanations when the 
Agency decides not to use available and applicable voluntary consensus 
standards.
    This direct final rule does not involve technical standards. This 
direct final rule merely replaces the interim gaseous emission 
measurement accuracy allowances for portable emission measurement 
systems with final values and delays the implementation schedule for 
the in-use PM testing program. Thus, we have determined that the 
requirements of the NTTAA do not apply.

J. Executive Order 12898: Federal Actions To Address Environmental 
Justice in Minority Populations and Low-Income Populations

    Executive Order (EO) 12898 (59 FR 7629 (Feb. 16, 1994)) establishes 
federal executive policy on environmental justice. Its main provision 
directs federal agencies, to the greatest extent practicable and 
permitted by law, to make environmental justice part of their mission 
by identifying and addressing, as appropriate, disproportionately high 
and adverse human health or environmental effects of their programs, 
policies, and activities on minority populations and low-income 
populations in the United States.
    EPA has determined that this rule will not have disproportionately 
high and adverse human health or environmental effects on minority or 
low-income populations because it does not affect the level of 
protection provided to human health or the environment. This direct 
final rule merely replaces the interim gaseous emission measurement 
accuracy allowances for portable emission measurement systems with 
final values and delays the implementation schedule for the in-use PM 
testing program.

K. Congressional Review Act

    The Congressional Review Act, 5 U.S.C. 801 et seq., as amended by 
the Small Business Regulatory Enforcement Fairness Act of 1996, 
generally provides that before a rule may take effect, the agency 
promulgating the rule must submit a rule report, which includes a copy 
of the rule, to Congress and the Comptroller General of the United 
States. We will submit a report containing this rule and other required 
information to the U.S. Senate, the U.S. House of Representatives, and 
the Comptroller General of the United States before publication of the 
rule in the Federal Register. A major rule cannot take effect until 60 
days after it is published in the Federal Register. This action is not 
a ``major rule'' as defined by 5 U.S.C. 804(2). This direct final rule 
is effective on May 12, 2008.

L. Statutory Authority

    The statutory authority for this action comes from 42 U.S.C. 7401-
7671q.

List of Subjects in 40 CFR Part 86

    Environmental protection, Administrative practice and procedure, 
Confidential business information, Labeling, Motor vehicle pollution, 
Reporting and recordkeeping requirements.

    Dated: February 28, 2008.
Stephen L. Johnson,
Administrator.

0
For the reasons set out in the preamble, title 40, chapter I of the 
Code of Federal Regulations is amended as follows:

PART 86--CONTROL OF EMISSIONS FROM NEW AND IN-USE HIGHWAY VEHICLES 
AND ENGINES

0
1. The authority citation for part 86 continues to read as follows:

    Authority: 42 U.S.C. 7401-7671q.

0
2. Section 86.1905 is amended by revising paragraph (c)(2) to read as 
follows:

Sec.  86.1905  How does this program work?

* * * * *
    (c) * * *
    (2) 2009 for PM testing.
* * * * *
0
3. Section 86.1912 is amended by adding new paragraphs (a)(3)(v) and 
(a)(5) and revising paragraph (a)(4) to read as follows:

Sec.  86.1912  How do I determine whether an engine meets the vehicle-
pass criteria?

* * * * *
    (a) * * *
    (3) * * *
    (v) NOX + NMHC: 0.67 grams per brake horsepower-hour.
    (4) Accuracy margins for portable in-use equipment when testing is 
not performed under the special provisions of Sec.  86.1930 for 2007 
through 2009 model year engine families that are selected for testing 
in any calendar year as follows:
    (i) NMHC using the emission calculation method specified in 40 CFR 
1065.650(a)(1): 0.02 grams per brake horsepower-hour.
    (ii) NMHC using the emission calculation method specified in 40 CFR 
1065.650(a)(3): 0.01 grams per brake horsepower-hour.
    (iii) NMHC using an alternative emission calculation method as

[[Page 13451]]

approved by the Administrator under 40 CFR 1065.915(d)(5)(iv): 0.01 
grams per brake horsepower-hour.
    (iv) CO using the emission calculation method specified in 40 CFR 
1065.650(a)(1): 0.5 grams per brake horsepower-hour.
    (v) CO using the emission calculation method specified in 40 CFR 
1065.650(a)(3): 0.25 grams per brake horsepower-hour.
    (vi) CO using an alternative emission calculation method as 
approved by the Administrator under 40 CFR 1065.915(d)(5)(iv): 0.25 
grams per brake horsepower-hour.
    (vii) NOX using the emission calculation method 
specified in 40 CFR 1065.650(a)(1): 0.45 grams per brake horsepower-
hour.
    (viii) NOX using the emission calculation method 
specified in 40 CFR 1065.650(a)(3): 0.15 grams per brake horsepower-
hour.
    (ix) NOX using an alternative emission calculation 
method as approved by the Administrator under 40 CFR 
1065.915(d)(5)(iv): 0.15 grams per brake horsepower-hour.
    (x) NOX + NMHC using the emission calculation method 
specified in 40 CFR 1065.650(a)(1): 0.47 grams per brake horsepower-
hour.
    (xi) NOX + NMHC using the emission calculation method 
specified in 40 CFR 1065.650(a)(3): 0.16 grams per brake horsepower-
hour.
    (xii) NOX + NMHC using an alternative emission 
calculation method as approved by the Administrator under 40 CFR 
1065.915(d)(5)(iv): 0.16 grams per brake horsepower-hour.
    (xiii) PM: To be determined by rulemaking as indicated in Sec.  
86.1935.
    (5) Accuracy margins for portable in-use equipment when testing is 
not performed under the special provisions of Sec.  86.1930 for 2010 or 
later model year engines families that are selected for testing in any 
calendar year as follows:
    (i) NMHC using any emission calculation method specified in 40 CFR 
1065.650(a) or an alternative emission calculation method as approved 
by the Administrator under 40 CFR 1065.915(d)(5)(iv): 0.01 grams per 
brake horsepower-hour.
    (ii) CO using any emission calculation method specified in 40 CFR 
1065.650(a) or an alternative emission calculation method as approved 
by the Administrator under 40 CFR 1065.915(d)(5)(iv): 0.25 grams per 
brake horsepower-hour.
    (iii) NOX using any emission calculation method 
specified in 40 CFR 1065.650(a) or an alternative emission calculation 
method as approved by the Administrator under 40 CFR 
1065.915(d)(5)(iv): 0.15 grams per brake horsepower-hour.
    (iv) PM: To be determined by rulemaking as indicated in Sec.  
86.1935.
* * * * *

0
4. Section 86.1930 is amended as follows:
0
a. By revising the section heading.
0
b. By redesignating paragraphs (a) through (f) as paragraphs (a)(1) 
through (a)(6).
0
c. By redesignating the introductory text as paragraph (a) introductory 
text.
0
d. By revising newly designated paragraph (a) introductory text.
0
e. By redesignating newly designated paragraphs (a)(4)(1) and (2) as 
paragraphs (a)(4)(i) and (ii).
0
f. By adding new paragraphs (a)(7) and (b).

Sec.  86.1930  What special provisions apply from 2005 through 2009?

    (a) We may direct you to test engines under this subpart for 
emissions other than PM in 2005 and 2006, and for PM emissions in 2007 
and 2008. In those interim periods, all the provisions of this subpart 
apply, with the following exceptions:
* * * * *
    (7) You must complete all the required testing and reporting under 
this subpart by the following dates:
    (i) November 30, 2007 for engine families that we designate for 
non-PM testing in 2005.
    (ii) November 30, 2008 for engine families that we designate for 
non-PM testing in 2006.
    (iii) May 31, 2010 for engine families that we designate for PM 
testing in 2007.
    (iv) September 30, 2010 for engine families we designate for PM 
testing in 2008.
    (b) For 2007 through 2009 all the provisions of this subpart and 
paragraph (a) of this section apply, with the following additional 
exceptions:
    (1) You must complete all the required testing and reporting under 
this subpart by the following dates:
    (i) November 30, 2009 for engine families that we designate for 
non-PM testing in 2007.
    (ii) March 31, 2010 for engine families that we designate for non-
PM testing in 2008.
    (iii) April 30, 2011 for engine families that we designate for non-
PM and PM testing in 2009.
    (2) You may conduct non-PM and PM testing on different vehicles for 
engine families that we designate in 2007 and 2008.
    (3) You may conduct PM testing as follows for 2007:
    (i) Test vehicles may be selected from a vehicle fleet that you own 
or otherwise directly control.
    (ii) Test vehicles may be operated by a driver that you employ.
    (iii) Each test vehicle must be operated on a route and under 
operating conditions that reasonably replicate the use of the selected 
vehicle type when operated in typical revenue service, unless otherwise 
approved by us.

0
5. Section 86.1935 is revised to read as follows:

Sec.  86.1935  What special provisions may apply as a consequence of a 
delay in the particulate matter accuracy margin report for portable 
emission measurement systems?

    (a) A memorandum entitled, ``Memorandum of Agreement, Program to 
Develop Emission Measurement Accuracy Margins for Heavy-Duty In-Use 
Testing'' describes a test program for establishing measurement 
accuracy margins related to testing under Sec.  86.1912(a)(4) which 
will be used for testing under this subpart. This document is available 
at http://www.epa.gov/otaq/hd-hwy.htm or at the mailing address 
specified in Sec.  86.1905(g).
    (b) If there is a delay in receiving the written final report for 
PM emissions described in the agreement referenced in paragraph (a) of 
this section, and that delay is not attributable to engine 
manufacturers failing to meet their commitments under that agreement, 
the following provisions apply:
    (1) If the delay is 3 months or less, we will delay the designation 
of engine families for testing in the applicable calendar year, as 
described in Sec.  86.1905(d), by the same number of additional whole 
months (rounded up) needed to complete the report.
    (2) If the delay is more than 3 months but less than 12 months, we 
may continue to designate engine families for testing under the special 
provisions described in Sec.  86.1930 for an additional year.
    (3) If the delay is longer than 12 months, the following approach 
is established for the applicable calendar year:
    (i) If the delay is longer than 12 months but less than 15 months, 
we will follow the steps described in paragraph (b)(1) of this section.
    (ii) If the delay is longer than 15 months, but, less than 24 
months, we will follow the steps described in paragraph (b)(2) of this 
section, for the applicable calendar year.
    (iii) If the delay is longer than 24 months, the emission testing 
program will go into abeyance.

[[Page 13452]]

    (c) If one or more engine manufacturers fail to meet commitments 
under the agreement described in paragraph (a) of this section and such 
a failure results in a delay in the final written report for PM 
emissions described in the agreement, the following provisions apply:
    (1) If the delay is 3 months or less, we will delay the designation 
of engine families for testing in the applicable calendar year, as 
described in Sec.  86.1905(d), by the same number of additional whole 
months (rounded up) needed to complete the report.
    (2) If the delay is more than 3 months but less than 12 months, the 
provisions of this subpart will not apply for the otherwise applicable 
calendar year, subject to the following provisions:
    (i) We may identify the number of engine families that would 
otherwise have been designated for testing in that calendar year for 
the delayed pollutant type and direct manufacturers to test that number 
of engine families under the special provisions described in Sec.  
86.1930 and additionally in any later calendar year once the provisions 
of this subpart begin for that pollutant type, without counting those 
accumulated engine families toward the allowable annual cap on the 
number of engine families specified in Sec.  86.1905.
    (ii) The normal 18-month period for testing and reporting results 
specified in Sec.  86.1905(d) is extended to 24 months for any 
accumulated engine-family designation described in paragraph (c)(2)(i) 
of this section. The additional time extensions for testing and 
reporting results as specified in Sec.  86.1905(d) also apply.
    (3) If the delay is longer than 12 months, the following approach 
is established for the applicable calendar year.
    (i) If the delay is longer than 12 months but less than 15 months, 
we will follow the steps described in paragraph (c)(1) of this section.
    (ii) If the delay is longer than 15 months, but less than 24 
months, we will follow the steps described in paragraph (c)(2) of this 
section for the applicable calendar year.
    (iii) If the delay is longer than 24 months, we will continue to 
follow the steps described in paragraphs (c)(1) and (c)(2) of this 
section, including the accumulation of engine families for testing 
until the report is received and the fully implemented program 
commences.
    (d) We may determine that any individual manufacturer's failure 
under paragraph (c) of this section constitutes a failure by all engine 
manufacturers.
    (e) Nothing in this section affects our ability to select engines 
from any model year beginning with model year 2007, or for gaseous 
emission testing.
    (f) If we determine that fundamental technical problems with 
portable in-use PM measurement systems are not resolvable in a 
reasonable time, the provisions of this subpart, as they apply to PM, 
will go into abeyance until we determine that suitable emission-
measurement devices are available for in-use testing.
    (g) Engine manufacturers contributing to the test programs 
described in the agreement referenced in paragraph (a) of this section 
may limit their testing under the special provisions described in Sec.  
86.1930 to five engines in each selected engine family.

[FR Doc. E8-4388 Filed 3-12-08; 8:45 am]

BILLING CODE 6560-50-P