[Federal Register Volume 70, Number 113 (Tuesday, June 14, 2005)]
[Rules and Regulations]
[Pages 34594-34626]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 05-11470]



[[Page 34593]]

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Part III





Environmental Protection Agency





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40 CFR Parts 9 and 86



Control of Emissions of Air Pollution From New Motor Vehicles: In-Use 
Testing for Heavy-Duty Diesel Engines and Vehicles; Final Rule

  Federal Register / Vol. 70, No. 113 / Tuesday, June 14, 2005 / Rules 
and Regulations  

[[Page 34594]]


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ENVIRONMENTAL PROTECTION AGENCY

40 CFR Parts 9 and 86

[OAR-2004-0072; AMS-FRL-7922-4]
RIN 2060-AM17


Control of Emissions of Air Pollution From New Motor Vehicles: 
In-Use Testing for Heavy-Duty Diesel Engines and Vehicles

AGENCY: Environmental Protection Agency (EPA).

ACTION: Final rule.

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SUMMARY: We are establishing a manufacturer-run, in-use emissions 
testing program for 2007 and later model year heavy-duty diesel 
vehicles. The ground-breaking in-use test program will require engine 
manufacturers to measure exhaust emissions from their diesel engines 
using portable emissions measurement systems. Also for the first time, 
all manufacturers will be regularly providing EPA with a significant 
quantity of emissions data generated from engines used in regular 
service, which EPA will evaluate to ensure the engines comply with 
specified emissions requirements. The rule is a result of an agreement 
between EPA and the Engine Manufacturers Association. This rule 
advances EPA's clean diesel activities by helping to ensure that the 
benefits of more stringent emission standards are realized under real-
world driving conditions.

DATES: This final rule is effective August 15, 2005.
    The incorporation by reference of certain publications listed in 
this regulation is approved by the Director of the Federal Register as 
of August 15, 2005.

ADDRESSES: EPA has established a docket for this action under Docket ID 
No. OAR-2004-0074. All documents in the docket are listed in the 
EDOCKET index at http://www.epa.gov/edocket. This rule relies in part 
on information related to our November 2002 final rule, which can be 
found in Public Docket A-2000-01. This docket is incorporated by 
reference into the docket for this action. Although listed in the 
index, some information is not publicly available, i.e., CBI or other 
information whose disclosure is restricted by statute. Certain other 
material, such as copyrighted material, is not placed on the Internet 
and will be publicly available only in hard copy form. Publicly 
available docket materials are available either electronically in 
EDOCKET or in hard copy at the Air Docket in the EPA Docket Center, 
EPA/DC, EPA West, Room B102, 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 legal holidays. The telephone 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: U.S. EPA, Office of Transportation and 
Air Quality, Assessment and Standards Division hotline at (734) 214-
4636 or [email protected]., or alternatively Carol Connell (734) 214-4349 
or [email protected]

SUPPLEMENTARY INFORMATION:

Regulated Entities

    This action will affect you if you produce or import new heavy-duty 
diesel engines which are intended for use in highway vehicles such as 
trucks and buses, or produce or import such highway vehicles, or 
convert heavy-duty vehicles or heavy-duty engines used in highway 
vehicles to use alternative fuels.
    The following table gives some examples of entities that are likely 
to be affected by these regulations:

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                                                                               Examples of potentially regulated
                 Category                   NAICS codes \a\    SIC codes \b\                entities
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Industry.................................            336112              3711  Engine and Truck Manufacturers.
                                                     336120
Industry.................................            811112              7533  Commercial Importers of Vehicles
                                                     811198              7549   and Vehicle Components.
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\a\ North American Industry Classification System (NAICS).
\b\ Standard Industrial Classification (SIC) system code.

    This list is not intended to be exhaustive, but rather provides a 
guide regarding entities likely to be regulated by this action. To 
determine whether particular activities may be regulated by this 
action, you should carefully examine the regulations. You may direct 
questions regarding the applicability of this action to the person 
listed in ``FOR FURTHER INFORMATION CONTACT.''

B. How Can I Get Copies of This Document and Other Related Information?

    1. Docket. EPA has established an official public docket for this 
action under Docket ID No. OAR-2004-0074. The official public docket 
consists of the documents specifically referenced in this action, any 
public comments received, and other information related to this action. 
Although a part of the official docket, the public docket does not 
include Confidential Business Information (CBI) or other information 
whose disclosure is restricted by statute. Documents in the official 
public docket are listed in the index list in EPA's electronic public 
docket and comment system, EDOCKET. Documents may be available either 
electronically or in hard copy. Electronic documents may be viewed 
through EDOCKET. Hard copy documents may be viewed at the EPA Docket 
Center, (EPA/DC) EPA West, Room B102, 1301 Constitution Ave., NW., 
Washington, DC. Docket in The EPA Docket Center Public Reading Room is 
open from 8:30 a.m. to 4:30 p.m., Monday through Friday, excluding 
legal holidays. The telephone number for the Public Reading Room is 
(202) 566-1744.
    This rule relies in part on information related to our November 
2002 final rule, which can be found in Public Docket A-2000-01. This 
docket is incorporated by reference into the docket for this action, 
OAR-2004-0074.
    2. Electronic Access. You may access this Federal Register document 
electronically through the EPA Internet under the ``Federal Register'' 
listings at http://www.epa.gov/fedrgstr/ Or you can go to the federal-
wide eRulemaking site at www.regulations.gov.
    An electronic version of the public docket is available through 
EDOCKET. You may use EDOCKET at http://www.epa.gov/edocket/ to view 
public comments, access the index listing of the contents of the 
official public docket, and to access those documents in the public 
docket that are available electronically. Once in the system, select 
``search,'' then key in the appropriate docket identification number.

Outline of This Preamble

I. Overview

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    A. Summary of the Rule
    B. Background on the Origins of This Rule
    C. Historical Context
    1. Genesis and Description of NTE Standards
    2. Current EPA In-Use NTE Testing
    3. Plans for Nonroad Diesel Engine In-Use NTE Testing
    D. California's Intent to Adopt an In-Use NTE Test Program
II. Details of the Rule
    A. Applicability
    B. Engine Family Selection
    1. Number of Engine Families
    2. Treatment of Nonconforming Engine Families
    3. Small or Unavailable Engine Families
    4. Engine Families Unsuitable for Testing
    C. Phase 1 Testing Scheme
    1. Focus of Initial Testing
    2. Engine Family Evaluation Criteria and Outcomes
    D. Phase 2 Testing Scheme
    1. Initiation and Focus of Additional Testing
    2. Number of Engines and Test Conditions
    E. Vehicle Pass Criteria
    F. NTE Threshold Specification
    1. Not-to-Exceed Standards
    2. Existing In-Use Compliance Margins
    3. New In-use Measurement Margin for Portable Measurement 
Systems
    i. Pilot Program Accuracy Margins
    ii. Final Program Accuracy Margins
    G. Considerations in Deciding on Remedial Action
    1. Manufacturers' Supplemental Information
    2. EPA's Testing and Supplemental Data
    3. Other Information
    H. Quantity of Data Collected
    I. Screening, Adjustment, and Mileage and of Test Vehicles
    J. Test Conditions
    K. Reporting Requirements
    1. Comprehensive In-Use Testing Reports
    2. Notification of Vehicle Failures
    3. Carve Outs, Deficiencies, or Other NTE Control Area 
Exclusions
    4. Incomplete, Invalid, or Voluntary Tests
    L. Measurement of Emission
    1. Pollutants and Other Emissions
    2. Portable Emission Measurement Systems--Status and 
Availability
    3. Measurement Accuracy Margin Development Program
    M. Pilot Program
    N. Public Availability of In-Use Testing Data
    O. Implications for Other EPA Programs
    1. EPA Testing and Supplemental Information
    2. Selective Enforcement Audit (SEA) Testing
    3. Deterioration Factor (DF) Testing
    P. Limitations of Warranty Claims
III. Economic Impact
IV. Public Participation
V. Statutory and Executive Order Review
VI. Statutory Provisions and Legal Authority

I. Overview

    This section summarizes the manufacturer-run, in-use Not-to-Exceed 
(NTE) testing program for on-highway, heavy-duty diesel vehicles and 
engines. It also contains background on the genesis of the rule, an 
overview of the origin and application of EPA's NTE emission standards, 
and a brief description of our ongoing in-use NTE. More detailed 
information on the NTE standards for heavy-duty diesel engines is 
contained in section II. F. 1. of this preamble.

A. Summary of the Rule

    We are establishing a manufacturer-run, in-use NTE testing program 
for vehicles with heavy-duty diesel engines, beginning in calendar year 
2005. The entire program is being adopted largely as we proposed in the 
Federal Register on June 10, 2004 (69 FR 32804) and June 21, 2004 (69 
FR 34326). There will be a pilot program in calendar years 2005 and 
2006 for gaseous pollutants (i.e., nonmethane hydrocarbons (NMHC), 
carbon monoxide (CO), and oxides of nitrogen (NOX)). In 
calendar years 2006 and 2007, there will be a pilot program for 
particulate matter (PM). Subsequent to these programs, the fully 
enforceable in-use test program begins. Therefore, the enforceable 
program starts in 2007 for gaseous pollutants and 2008 for PM. In those 
years, the test program will apply to 2007 and later model year 
engines.
    This testing program addresses a long standing need to monitor the 
emissions performance of the engines installed in these on-highway 
vehicles when they are operated under a wide range of real world 
conditions. It is specifically intended to monitor compliance with the 
NTE exhaust emission standards and to help ensure that heavy-duty 
diesel engines will comply with all applicable emission standards 
(e.g., including those based on the Federal Test Procedure (FTP)) 
throughout their useful lives. Background on our NTE standards is 
presented in sections I. B. and C. of this Preamble.
    The new testing program will, for the first time, require engine 
manufacturers to assess in-use exhaust emissions from heavy-duty diesel 
vehicles using onboard, portable emission measurement systems during 
typical operation on the road. Previously, engine emissions testing 
involved removing the engine from the vehicle and testing the engine in 
a laboratory on an engine dynamometer. Starting in the mid-1990s, EPA 
facilitated research into portable systems by developing and using 
prototype systems on a more limited basis in its compliance programs. 
Vehicles were instrumented with portable systems to measure their 
emissions performance during real-world operating conditions. It became 
clear that these systems offered advantages over conventional 
approaches to assess in-use exhaust emissions from engines for design 
improvement, research, modeling, and compliance purposes.
    Under the program, we will designate a certain number of heavy-duty 
diesel engine families for testing. Generally, no more than 25 percent 
of a manufacturer's engine families would be designated in any single 
year. We expect manufacturers will use their existing customer 
relationships and create new lines of communication with customers to 
recruit appropriate test vehicles from fleets or individual owners. 
Each selected vehicle will be equipped with a portable emission 
measurement system and driven by its normal operator, with a normal 
payload, over its regular driving route. All data and test results will 
be reported to EPA on a regular basis. The manufacturer of a designated 
heavy-duty engine family will pay for all of the expenses associated 
with the planning, vehicle procurement, testing, and data reporting.
    The test program is composed of two phases. In the first phase of 
testing (Phase 1) the manufacturer will test a minimum of five and a 
maximum of 10 vehicles per engine family selected for testing. If five 
out of the first five vehicles, or five out of the first six vehicles 
pass a specified vehicle pass criteria, or vehicle testing criteria, no 
further testing or other data relating to that diesel engine family 
will be required from the manufacturer that year. However, we may 
choose that engine family for testing again in a later year. If the 
above conditions are not met, then a total of 10 vehicles will be 
tested in Phase 1. If eight out of the 10 vehicles pass the vehicle 
testing criteria, no further testing or other data relating to that 
diesel engine family will be required from the manufacturer for that 
year.
    In all other cases, we will decide on a course of action depending 
on the number of vehicles from the designated engine family that fail 
to pass the vehicle testing criteria and other factors. In making our 
decision, we will thoroughly review the test results, consult with the 
engine manufacturer, allow the manufacturer to provide additional data, 
and consider other pertinent information. The action may include, but 
is not limited to, one of the following:
    1. No further action because no significant nonconformance issues 
are indicated;
    2. Initiate the second phase of testing (Phase 2); or
    3. Seek some form of remedial action.

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    If five or fewer of the Phase 1 test vehicles satisfy the vehicle 
pass criteria, EPA may require the manufacturer to conduct Phase 2 
testing. If only six or seven of the Phase 1 test vehicles pass the 
vehicle pass criteria, EPA may require the manufacturer to conduct 
Phase 2 testing under these regulations if the manufacturer agrees to 
perform such testing. However, if Phase 2 testing is conducted for any 
reason, even if the manufacturer elects to pursue the next phase of 
testing voluntarily, we may direct that up to 10 additional vehicles be 
tested. In this phase, we may also focus testing on one or more engine 
configurations within the engine family. Additionally, we may specify 
certain driving routes or other driving conditions (e.g., geographic 
conditions or time of year). The purpose of these additional 
specifications is to better understand how widespread or under what 
conditions the Phase 1 test vehicles are failing to pass the vehicle 
pass criteria. In those instances, the specifications would be based on 
the Phase 1 test conditions that indicated a potential nonconformity.
    As with Phase 1 testing, any remedial action we may choose to 
pursue based on Phase 2 testing will be made only after a thorough 
review of the test results, consultation with the engine manufacturer, 
and consideration of other pertinent information.
    The in-use testing program is primarily designed as an information-
gathering process that will inform EPA's decision-making. The results 
of in-use testing for any particular engine family will not necessarily 
lead to, or necessarily insulate an engine family from, appropriate 
remedial actions, depending on the particular results of the testing 
and other information in EPA's possession. However, EPA believes that 
the results of the in-use testing and information gathered by the 
program will be a critical resource for EPA in determining how to 
direct our limited resources.
    We expect that the wealth of in-use test data generated by the 
program will have a number of valuable uses in addition to monitoring 
heavy-duty diesel engines for NTE compliance purposes under the 
program. For example, though EPA would not engage in routine NTE 
testing of engines or engine families that satisfy the Phase 1 test 
criteria unless new information indicates that a nonconformity exists, 
we may use the in-use data along with other information to make 
independent evaluations about the possible need to pursue further 
testing or actions. We may also use the information in the development 
of in-use emission factors for emissions and air quality modeling. 
Further, manufacturers have told us that they expect the proposed 
program will fortify the traditional laboratory-based engine 
development process. This will be done by enhancing a manufacturer's 
ability to evaluate the performance of the engine and emissions control 
system under real world operating conditions and use, the results of 
which may be used to create cleaner and more durable future engine 
designs. Finally, the in-use test data will also be available to the 
public for review and analysis.
    As previously described, the in-use NTE testing program will be 
fully enforceable beginning in 2007 for gaseous pollutants and 2008 for 
PM. To ensure a successful launch of this new program, there is a 
mandatory pilot program for gaseous emissions in calendar years 2005 
and 2006, and 2006 and 2007 for PM using only the first phase (Phase 1) 
of testing. During these years both EPA and the heavy-duty diesel 
engine manufacturers will gain valuable experience with the in-use 
testing protocols, and the generation, interpretation, and reporting of 
in-use emissions data. If an engine family fails to meet the vehicle 
pass requirements of Phase 1 testing under the pilot program, we will 
not pursue any form of remedial action based solely on that data. 
However, we may utilize such information in conjunction with our own 
test data and other information to assess or pursue any enforcement or 
remedial action that otherwise may be authorized during that time.
    The success of this testing program depends on ensuring that the 
new onboard, portable measurement systems are correctly measuring 
exhaust emissions in the field. To this end, we are establishing 
measurement ``accuracy'' margins for these new systems. The purpose of 
the margins is to account for the emissions measurement variability 
associated with these units in the field. During the pilot program 
years, manufacturers will use interim margins that we believe represent 
an upper bound of the possible instrumentation variability based on our 
experience with portable and laboratory measurement systems. Accuracy 
margins for the fully enforceable program are being developed through a 
comprehensive research, development, and demonstration program. The 
program is described in a Memorandum of Agreement and summarized in 
section II. L. 3. of this preamble.

B. Background on the Origins of This Rule

    On October 6, 2000, we published a final rule that promulgated new 
emission standards for on-highway heavy-duty engines. See 65 FR 59896. 
The final rule included new standards, applicable to 2007 and later 
model year heavy-duty diesel engines, called NTE standards. These 
standards are designed to apply under any conditions reasonably 
expected to occur during normal vehicle use. The test procedure for the 
NTE standards is different from most previous test procedures in that 
it is not based on a rigidly timed test cycle, but instead allows 
testing at a wide, though bounded, range of engine and ambient 
conditions that can occur in normal vehicle operations.
    These NTE standards, as well as other provisions of the final rule, 
were particularly designed to ensure that engines and vehicles 
manufactured to meet the FTP standards over the engine certification 
test cycle in the laboratory continued to effectively control emissions 
under any conditions reasonably expected to occur during normal vehicle 
use. The final rule described our concerns regarding additional factors 
that may jeopardize the emission reductions expected in-use from the 
standards promulgated in that rule. See 65 FR at 59910 (October 6, 
2000). Among these factors was the absence of an effective in-use 
compliance program for heavy duty engines and vehicles. We noted that 
we had received broad support from states, environmental organizations, 
and industry to move forward with developing a proposal to address this 
issue. The Engine Manufacturers Association (EMA) committed to work 
diligently and cooperatively with EPA and the California Air Resources 
Board (CARB) to resolve the open questions in a timely fashion. See 64 
FR 58472, 58514 (October 29, 1999).
    EMA and certain individual engine manufacturers challenged EPA's 
adoption of NTE standards in several rules.\1\ EPA, CARB and the engine 
manufacturers, as well as state and environmental organizations, 
engaged in lengthy and ultimately productive discussions to settle 
these challenges and to go forward with a regulatory program that 
included robust measures to ensure that emission controls implemented 
to meet EPA and CARB

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standards remain effective under all normal vehicle operation. One 
result of these discussions was the identification of the basic program 
elements for a manufacturer run, in-use NTE testing program, and an 
agreement to go forward with a rulemaking to implement such a program 
for on-highway heavy-duty diesel engines.\2\ Today's action essentially 
completes that rulemaking process.
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    \1\ See International Truck et al. v. EPA, (DC Cir Nos. 00-1510 
and 00-1512); EMA et al v. EPA (DC Cir. Nos. 01-1129 and 02-1080); 
International Truck v. EPA, No. 01-1137; EMA v. EPA, (DC Cir. No. 
00-1066); and EMA v. EPA, (DC Cir. No. 03-1007)
    \2\ See Final Settlement Agreement, dated June 2, 2003, in the 
cases cited above.
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C. Historical Context

1. Genesis and Description of NTE Standards
    Traditionally, heavy-duty diesel vehicles and engines have been 
certified to exhaust emission standards in the laboratory. More 
specifically, the engine is tested separately from the vehicle using an 
engine dynamometer and a prescribed ``driving cycle.'' Monitoring for 
compliance with the applicable emission standards during the life of 
these vehicles (i.e., in-use) was also determined by removing the 
engine from the vehicle and then testing it using the same laboratory 
measurement procedures. Several years ago we became concerned that in-
use emissions might inappropriately exceed the applicable standards 
when engines were operated under conditions not found during 
traditional laboratory testing (i.e., off-cycle emissions). An 
investigation into off-cycle emissions performance confirmed that 
advances in engine technology had allowed some manufacturers to design 
engines with control strategies which resulted in substantially greater 
levels of emissions during typical real-world operating conditions than 
were emitted during the laboratory testing cycle required for 
certification.
    To close the gap between laboratory and real world emissions 
performance, and to deter manufacturers from using such strategies in 
the future, we developed NTE emission standards for heavy-duty diesel 
engines. The NTE requirements establish an area or zone under the 
torque curve of an engine where emissions must not exceed a specified 
value for any of the regulated pollutants.\3\ The provisions also 
define a specific range of operating conditions, i.e., temperature, 
altitude, and humidity. The test itself does not involve a specific 
driving cycle of any specific length, i.e., mileage or time, rather it 
involves all driving that could occur within the bounds of the NTE 
control area. The vehicle (or engine) is operated under conditions that 
may reasonably be expected to be encountered in normal vehicle 
operation and use, including operation under steady-state or transient 
conditions and under varying ambient conditions. Within the NTE control 
area, emissions must not exceed a specified multiple of the underlying 
FTP standards. For heavy-duty diesel engines, this multiple is 
generally 1.25 or 1.50 times the applicable FTP standards.
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    \3\ Torque is a measure of rotational force. The torque curve 
for an engine is determined by an engine ``mapping'' procedure 
specified in the Code of Federal Regulations. A graphical 
representation of the NTE control area is contained in the Technical 
Support Document accompanying this proposed rule.
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    Initially, the NTE requirements were a key provision in consent 
decrees with several manufacturers of heavy-duty diesel engines that 
resulted from the investigation described above. This new requirement 
became effective in 1998 for most manufacturers involved in those 
consent decrees, and by November 2002 had been applied for such 
manufacturers to the NOX standards set to go into effect in 
model year 2004. NTE requirements are currently being used as a 
screening tool for 2004 through 2006 model year engines not covered by 
the consent decrees. The NTE requirements will be mandatory for all 
2007 and later heavy-duty diesel engines. We also promulgated NTE 
standards for certain other mobile sources.\4\
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    \4\ The use of NTE testing as a screening tool for 2004-2006 on-
highway heavy-duty diesel engines is discussed in Advisory Circular 
24-3. The final rule applying the NTE to 2007 and model year engines 
is published at 65 FR 59896 (October 6, 2000). Other final rules 
promulgated by EPA extended the NTE approach to new marine 
compression-ignition engines at or above 37 horsepower, 64 FR 73300 
(December 29, 1999) and 67 FR 68242 (November 8, 2002); and to a new 
and more stringent phase of on-highway heavy duty engine standards 
66 FR 5002 (January 18, 2001).
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    The NTE test can be conducted in an emissions testing laboratory 
using an appropriate dynamometer or while the vehicle is being used on 
the road. It is this last feature that makes NTE testing a very 
powerful in-use compliance monitoring tool. In-use testing and 
compliance become much easier with the NTE standards since emissions 
may be sampled during normal vehicle use on the road using portable 
emission measurement systems. As already mentioned, traditional 
laboratory engine testing over a very specific driving schedule 
requires the engine be removed from the vehicle rendering in-use 
testing prohibitively cumbersome and expensive. Further, engine-based 
testing cannot account for the drive train and sensor interactions 
which occur during normal vehicle operation. As such, testing during 
normal vehicle use, using an objective numerical standard, makes 
enforcement easier and provides more certainty of what is occurring in-
use versus a fixed laboratory procedure.
2. Current EPA In-Use NTE Testing
    We have been conducting our own in-use NTE testing of heavy-duty 
diesel engines for the past four years. Over that period, an average of 
40 on-highway vehicles were tested annually. Vehicles are procured 
through the voluntary participation of commercial and municipal fleets 
and emissions are tested during normal service operation. Portable 
emission measurement systems are installed on-site at the fleet's 
facility before the vehicle begins its service day. EPA uses a 
prototype portable sampling system which measures hydrocarbons (HC), 
carbon monoxide (CO), and oxides of nitrogen (NOX). Our 
experience with this program has aided us in developing today's final 
rule for a manufacturer-run, in-use NTE test program.
3. Plans for Nonroad Diesel Engine In-Use NTE Testing
    On June 29, 2004, we published NTE requirements that accompany our 
new transient-cycle emission standards for nonroad diesel engines (69 
FR 38957). This new test cycle will be phased into the certification 
requirements between 2011 and 2013, depending on an engine's horsepower 
rating. The NTE provisions are similar to those described in this 
notice for on-highway heavy-duty diesel engines. Presently, we are 
developing an outline for a proposed manufacturer-run, in-use NTE test 
program for nonroad diesel engines covered by the new requirements. We 
expect this program will have similar characteristics to today's rule, 
but will address some unique issues pertaining to the nonroad market. 
Among these are such things as the widely varying power ranges of 
nonroad engines (including those much smaller and much bigger than 
highway engines), and broad array of equipment applications that may 
use the same engine type or model. We expect the program to have a 
pilot program similar to the pilot program in today's rule and to be 
initiated consistent with the introduction of emission control 
requirements for nonroad engines built in conformance with the new 
standards, which are based on aftertreatment. The resulting 
implementation date may be as early as 2011.

[[Page 34598]]

D. California's Intent To Adopt an In-Use NTE Test Program

    California's involvement in the development of this program was 
critical in assuring that engine manufacturers are subject to a 
consistent national in-use NTE test program. CARB intends to adopt an 
identical program soon. EPA and CARB expect to coordinate in the annual 
selection of engine families to be in-use tested and to work together 
in determining whether Phase 2 testing is warranted for families where 
the number of passing engines in Phase 1 does not automatically lead to 
no further testing. CARB has its own authority and decision process in 
determining remedial action for failing families, but CARB expects to 
work with EPA and the manufacturers in this process.

II. Details of the Rule

    This section presents the details of the two-phase in-use NTE 
testing program for heavy-duty diesel vehicles. It focuses primarily on 
the fully enforceable program that will begin with the 2007 model year 
for gaseous pollutants and 2008 for PM. A number of the special 
features for a pilot program during the two years preceding each of the 
fully enforceable dates described above are also described. Key aspects 
of the pilot program are further summarized in section II. M. of this 
preamble.
    We have initiated a comprehensive research, development, and 
demonstration program that is designed to identify new accuracy 
measurement margins for portable measurement devices. When completed, 
the accuracy margins are expected to be adopted for use in the fully 
enforceable program. EPA has modified the testing requirements during 
the pilot program for manufacturers that participate in the accuracy 
margin development effort. In addition, the fully enforceable program 
for either gaseous emissions or PM may be postponed if the process of 
identifying the final accuracy margins is significantly delayed beyond 
the originally scheduled completion dates. The program for developing 
the measurement accuracy margin is described in section II. L. and the 
implications of this program are described throughout this preamble as 
appropriate.
    The in-use NTE testing program we are promulgating today is nearly 
identical to the program we proposed in the Federal Register on June 
10, 2004 (69 FR 32804) and June 21, 2004 (69 FR 34326). The features of 
the program that were revised based on public comments received on the 
proposed rule are described in this section. Our response to the 
significant public comments is contained in the Summary and Response to 
Comments document that accompanies this final rule.

A. Applicability

    The requirements apply to diesel engines certified for use in 
heavy-duty vehicles (including buses) with gross vehicle weight ratings 
(GVWR) greater than 8,500 pounds. However, the requirements do not 
apply to any heavy-duty diesel vehicle that was certified using a 
chassis dynamometer under our CAP 2000 certification program, including 
medium-duty passenger vehicles with GVWRs of between 8,500 and 10,000 
pounds. The manufacturer of heavy-duty diesel engines subject to the 
program is responsible for all of the costs associated with project 
planning, vehicle procurement, testing, and reporting.
    We are establishing a fully enforceable, two-phase test program for 
heavy-duty diesel engines beginning in 2007 for gaseous pollutants and 
2008 for PM. In those years, the fully enforceable test program will 
apply to 2007 and later model year engines. We are also establishing a 
mandatory pilot program for gaseous pollutants in calendar years 2005 
and 2006, and for PM in calendar years 2006 and 2007. Under the gaseous 
emission pilot program, 2002 through 2006 model year vehicles may be 
tested. Under the PM pilot program, 2002 through 2007 model year 
vehicles may be tested. The pilot program will utilize only the first 
phase of the two-phase program developed subsequent fully enforceable 
program.
    We had originally proposed to require emissions testing for PM 
concurrently with gaseous emissions. In doing so, we acknowledged that 
more development work was needed before portable PM-measurement systems 
were available. However, it appeared possible to complete this work 
prior to the start of the pilot program in 2005. The engine 
manufacturers commented that the instrumentation to measure PM 
emissions onboard a vehicle was not available. Further, they stated 
that a PM requirement should not be included in the program until such 
time as validated, properly field-tested onboard devices become 
commercially available. Our evaluation of the status of portable PM 
measurement technology shows that the development of portable devices 
has progressed, but not as quickly as anticipated. We currently expect 
portable PM measurement systems will be available for 2006. Therefore, 
we have delayed the start of the PM pilot program one year until that 
date, i.e., 2006. Similarly, the enforceable program for PM will now 
start in 2008. A more detailed discussion of both gaseous and PM 
portable measurement systems is presented in section II. L.
    Engine manufacturers commented that the model year applicability 
for the pilot program was too broad. Specifically, they argued that the 
plot should be limited to 2005 and 2006 model year vehicles because 
some 2002 through 2004 engine families were not specifically certified 
to meet NTE standards. We agree with the manufacturers to the extent 
that engine families which were not certified in compliance with the 
NTE requirements should not be tested in the manufacturer-run program. 
However, their recommended exclusion is also too broad. Instead, we 
will include model years back through 2002 in the pilot program, but we 
will only select engines which have been designed to comply with the 
NTE. This includes engines certified under consent decree requirements, 
California NTE regulations, and the voluntary NTE provisions contained 
in EPA guidance document VPCD 98-13 and Advisory Circular 24-3.\5\ EPA 
will only select engine families for which the manufacturer's Statement 
of Compliance specifically describes the engine as being designed to 
comply with the NTE either by regulation or voluntarily. For engines 
not designed to comply with the NTE, EPA does reserve the right to use 
the NTE as a means to evaluate the appropriateness of a manufacturer's 
auxiliary emissions control devices (i.e., screen for defeat devices) 
as explained in the EPA guidance documents above. In such a case, EPA 
would conduct the testing and would not require the manufacturers to do 
so under the in-use program.
---------------------------------------------------------------------------

    \5\ Add titles, etc., for the two documents here.
---------------------------------------------------------------------------

B. Engine Family Selection

1. Number of Engine Families
    EPA currently estimates that 71 heavy-duty diesel engine families 
are being certified by 13 manufacturers that would potentially be 
eligible for in-use testing under this proposed program. Our goal in 
deciding how many engine families should be tested each year is to 
conduct enough testing to assure in-use compliance with the applicable 
emission standards, while at the same time keep the program from being 
overly burdensome for the engine manufacturers.
    As a general premise, we believe it is a reasonable test all of a 
manufacturer's

[[Page 34599]]

heavy-duty diesel engine families over a four-year period. So, we will 
to designate up to 25 percent of a manufacturer's total number of 
engine families for testing per calendar year. The number of engine 
families that are tested in a given year will be based on the actual 
number of engine families certified by that manufacturer in that year, 
rounded up or down as appropriate. However, for the purpose of 
calculating the number of engine families certified in a given year, we 
will only include engine families with a production volume greater than 
1,500 engines. This designation strategy will provide in-use test data 
for most of the diesel engine population and, at the same time, not 
overburden manufacturers that have several small production engine 
families. If a manufacturer has three or fewer engine families that 
exceed the annual 1,500 engine production limit, including when a 
manufacturer has no families with production levels above that limit, 
we will only test one engine family per year.
    We will also cap the maximum number of families designated for 
testing over any four-year period to the average number of families for 
that manufacturer over that four-year period, rounding up or down as 
appropriate.
    Several examples showing how many engine families we can designate 
each year for testing under the proposed in-use, manufacturer-run 
program are provided below. The illustrations are arranged in an 
increasing order of complexity. Additional examples and other relevant 
information are presented in the Technical Support Document for today's 
action.
    The first two examples illustrate how we would calculate the annual 
number of engine families for testing using the 25 percent per year 
limit for engine families above the 1,500 units per year level, and 
when a manufacturer only has engine families with annual production 
less than 1,500 units per year. First, Manufacturer A has 12 certified 
engine families in production in a given model year, and only 8 out of 
the 12 families have annual productions levels of over 1,500 engines. 
Then the maximum number of engine families we can designate for in-use 
testing from Manufacturer A in that calendar year is 2 (i.e., 25 
percent of 8 engine families). Second, Manufacturer B has 8 engine 
families, all with annual production less than 1500 engines. In this 
situation, we are limited to selecting only 1 engine family for testing 
in that calendar year.
    The next two examples are somewhat more complex. The first of these 
examples shows how the four-year limitation (i.e., cap) on the maximum 
number of designated engine families works with a constant number of 
engine families over time. First, Manufacturer C has 3 engines families 
in production in each of four consecutive years, or an average of 3 
engine families per year over a four-year period. Additionally, all the 
families have annual production volumes over 1,500 units. In this 
situation, 1 engine family per year can be designated for testing in 
three of the four calendar years. However, no family can be selected in 
one of the four years because the number of families tested would 
otherwise exceed the average number of families produced over the four-
year period. Second, Manufacturer D produces 7 engine families each 
year during a four-year period and all the families are over 1,500 
units per year. In this situation, we can select up to 2 engine 
families per year under the 25 percent annual limit (i.e., 25 percent 
of 7 families is 1.75, which rounds up to 2). So, 2 engine families can 
be designated for testing in three of the four calendar years, but only 
1 family can be tested in a fourth year because the four-year cap on 
the maximum number of engines tested would otherwise be exceeded.
    The last example is the most complex. It once again illustrates how 
the four-year cap on the maximum number of designated engine families 
applies, but in this case for a scenario were the number of engine 
families varies over time, and when the fully enforceable program is 
just beginning (i.e., the 2007 calendar year). Manufacturer E produces 
6 engine families in the 2004 through 2009 model years and 7 engine 
families in the 2010 through 2014 model years. We can order testing for 
2 engine families each in 2007, 2008 and 2009 under the 25 percent 
annual limit (i.e., 25 percent of 6 families is 1.5, which rounds up to 
2 using standard rounding practices \6\). In 2010, however we cannot 
order testing of any families because the average number of certified 
families in the four years preceding testing (including the current 
model year) is 6.25, rounded down to 6. Since we have already tested 6 
engine families in the previous three years, we cannot test another 
engine family in the fourth year because the total number of engine 
families in the four-year period would be greater than the average 
number of engine families produced in the past four years (i.e., 6). In 
2011, we can order the testing of 2 families under the 25 percent 
annual limit. Here, the average number of engine families in the four 
years preceding testing (including the current model year) is 6.5. This 
rounds down to 6, again using standard rounding practices. Since we 
have only tested 4 engine families in the previous three years, we can 
test another 2 engine families in the fourth year. For 2012 the average 
number of engine families in the four-year period is 6.75 (6 families 
in model year 2009 and 7 families in model years 2010 through 2012). 
Rounding up from 6.75, we can order testing for 7 engine families in 
the four-year period prior to 2012. Since we have only ordered testing 
for 4 families in the previous three years, we can order testing for 2 
families under the 25 percent annual limit in 2012. Similarly, we can 
order the testing of 2 families in 2013. However, in 2014, we can order 
testing for only 1 engine family because the average number of families 
produced in the applicable four-year period is 7 and we have already 
ordered testing for 6 engine families in the previous three years.
---------------------------------------------------------------------------

    \6\ See, ``Guide for the Use of the International System of 
Units (SI), NIST Special Publication 811, 1995 Edition, National 
Institute of Standards and Technology, U.S. Department of 
Commerce.'' Under the rounding convention contained in this 
reference, when the first digit discarded is exactly 5, the last 
digit retained should be rounded upward if it is an odd number, but 
no adjustment made if it is an even number.
---------------------------------------------------------------------------

    Only the most recent and accurate sales information will be used to 
identify engine families with annual U.S.-directed production volumes 
of 1,500 engines or less when determining the potential number of 
engine families we may require a manufacturer to test in any year. When 
an engine family has reached the end of its production, the actual 
sales for an engine family that is already required to be submitted to 
EPA at the end of each model year as part of the certification program 
will be used for this purpose. If the engine family has not ended 
production and final sales are not available, then we may use the sales 
projection that is provided as part of a manufacturer's certification 
application.
    After the number of engine families that are eligible for in-use 
testing is determined for a calendar year, we may select any engine 
family for testing that a manufacturer has in production that model 
year, or any other engine families produced by the manufacturer in 
previous model years covered by the testing program. We also reserve 
the right to designate any engine family previously tested under this 
program in a subsequent calendar year. This will allow us to evaluate 
the emission performance of heavy-duty diesel vehicles as they 
accumulate mileage over a number of years. It will also allow us to 
assess a manufacturer's remedy of any previous

[[Page 34600]]

nonconformance problem, which was discovered under the proposed in-use 
testing program. When evaluating past model years for testing, we will 
also consider such factors as the likely number of vehicles remaining 
in service and their perspective mileage relative to their certified 
useful life.
    We intend to make our engine family selections by approximately 
June 30 of each calendar year. Waiting until the mid-point of the 
calendar year to select engine families for testing increases the 
likelihood that EPA will be able to choose from a manufacturer's entire 
product offering for that same model year. Typically, all of a 
manufacturer's engines for a given model year are covered by a 
certificate of conformity by the mid-point of that same calendar year. 
For example, all 2007 model year engines are expected to be certified, 
in most cases, by June 30, 2007. This also allows EPA to calculate the 
number of engine families to be ordered for testing in a given calendar 
year without having to continually update that number and order further 
testing. In the event one or more engine families are certified by a 
manufacturer after June 30, we will update our calculation of the 
number of engine families we can order tested in that calendar year 
and, if appropriate, order further testing. We still may select any 
engine family by the end of that calendar year for testing, including 
the newly certified family, with the understanding that the 
manufacturer is allowed the same period of time for testing and 
reporting results from each engine family from the date of selection.
    Regarding the testing and reporting period, we are allowing 18 
months from the time an engine family is designated for testing until 
the results must be reported to us. A manufacturer may request up to 
six additional months to complete and report Phase 2 test results if 
there is a reasonable basis for needing more time. Further, a 
manufacturer may request an additional six month extension. More 
details on the testing and reporting period is presented in section 
II.K.1.
    Engine manufacturers commented that EPA should specify a single 
point in time for identifying engine families that must be tested for 
that calendar year's selection since the number of certified families 
changes over the year. We believe the proposed selection protocol 
fairly balances our desire to maximize the number of engine families 
that may be designated for testing in any year, with a manufacturer's 
need for certainty in its planning process and a manageable testing 
burden. As already noted, manufacturers normally certify all or most of 
their engine families by June 30 of each year. So a manufacturer will 
know either its complete liability under the in-use testing program or 
the bulk of its responsibility by that time. Because of the lead time 
normally associated with engine development and the certification 
process, a manufacturer planning to certify an engine family after 
approximately June 30 should calculate the possible in-use testing 
exposure associated with that action and plan accordingly relative to 
the expenditure of resources. This does not seem overly burdensome, 
since all selected engine families are provided the same testing and 
reporting period, regardless of the date the family was selected for 
testing (see section II.K.1. of this preamble for a discussion of the 
testing and reporting period). Therefore, we are adopting the engine 
family selection protocol as proposed.
2. Treatment of Nonconforming Engine Families
    If there is clear evidence of an emissions nonconformity with 
respect to one or more of that manufacturer's families, a manufacturer 
may be required to test a number of engine families that exceeds the 
numerical limits described in Section II.B.1. above. More specifically, 
we may require any engine family for which such a determination is made 
be tested in the manufacturer-run, in-use NTE testing program in any 
subsequent year without counting toward the otherwise applicable limit 
on the number of families we may select in any year.
    For the purposes of the in-use testing program only, if an engine 
family was subject to a recall action (voluntary or mandatory), that 
failure is clear evidence of a nonconformity for that engine family and 
any carryover engine family produced in a prior or subsequent model 
year.\7\ \8\ The remedied engine family may have been normally selected 
for testing under the proposed in-use testing program, but did not pass 
the vehicle pass criteria and was subject to a recall action. 
Alternatively, the remedied family may have been recalled based on the 
results of an EPA in-use testing program. This linkage of carryover 
engine families helps ensure that manufacturers will be sufficiently 
motivated to remedy in a timely manner any noncompliance which is 
strongly suspected to cut across multiple engine families. As with 
other aspects of this program, we will consult with the manufacturer 
when contemplating a determination of clear evidence. An engine family 
selected using the ``no count'' designation may have never been tested 
under the proposed manufacturer-run, in-use NTE testing program, or it 
may have been tested but no remedial action was initiated based on the 
test results.
---------------------------------------------------------------------------

    \7\ Manufacturers designate carryover engine families during the 
certification process. The carryover designation indicates that the 
engine family for which a certificate is being requested is nearly 
identical to an engine family which has been previously certified. 
In such instances, the emissions results from the previously 
certified engine family are directly applied or carried over to the 
engine family for which a certificate is being requested.
    \8\ Section 207 (c) of the Clean Air Act (CAA) authorizes EPA to 
require manufacturers to recall vehicles or engines for the purpose 
of remedying noncompliance with EPA regulations that occur during 
the regulatory useful life of the vehicle or engine. EPA may only 
require a recall when the noncompliance involves a substantial 
number of a class or category of vehicles or engines which have been 
properly maintained and used. (See CAA Section 207(c)). The 
procedures EPA uses to administer emissions recalls are described in 
40 CFR Part 85 Subpart S.
---------------------------------------------------------------------------

3. Small or Unavailable Engine Families
    We recognize the possibility that a manufacturer may find it 
difficult or impossible to locate a sufficient number of vehicles from 
a designated diesel engine family to complete testing even after a 
diligent and good faith recruiting effort. This might especially happen 
for families with limited sales, or if a significantly older model year 
is designated for testing. Of course, we will attempt to avoid such an 
outcome in our engine family selection process. However, if a 
manufacturer encounters this problem and cannot complete either the 
Phase 1 or Phase 2 testing in the time frame or manner required, the 
manufacturer may ask us to modify the testing requirements for such 
engine family or designate a different diesel engine family for 
testing.
4. Engine Families Unsuitable for Testing
    The Detroit Diesel Corporation (DDC) commented that certain chassis 
and applications are entirely unsuited for in-use testing, and that 
these should be excluded from the program. As an example, the company 
identified fire truck and emergency vehicles with unique engine 
families as falling into this category because they can not be 
instrumented without compromising the utility of the chassis. Also, DDC 
suggested that there are numerous applications where interior space 
constrains would not allow mounting the test equipment inside the cab 
and still provide for the presence of a technician. In this latter 
regard, the company noted that weatherproof systems are yet to be 
developed by instrument manufacturers. Consequently, DDC recommended 
that EPA not require in-use testing of engine

[[Page 34601]]

families constrained by such application considerations.
    In general, EPA will avoid selecting engine families, and vehicle 
chassis and applications where testing with portable emissions sampling 
systems is infeasible, impractical, or unsafe. We anticipate that such 
testing challenges would generally be isolated to a specific sub-class 
of vehicle chassis or applications. Therefore, engine families are not 
expected to be wholly eliminated from consideration for reasons of 
portable testing incompatibility. To the extent incompatible engine 
families exist, they will likely be characterized by small volume 
annual production of fewer than 1,500 units. In general, these low 
production engine families will be selected for testing less frequently 
than their larger volume counterparts which makes it easier to avoid 
compatibility issues.
    We also believe that the in-use testing requirements provide 
manufacturers sufficient latitude to avoid selecting vehicles which are 
not suitable for in-use testing. In our own in-use testing with 
portable emission measurement devices, we have successfully tested both 
fire trucks and emergency vehicles. Additionally, the final regulations 
allow a manufacturer to reject a particular vehicle from the program if 
it is found to be unsuitable without prior notification to EPA. Any 
rejected vehicle must be replaced with another perspective test 
vehicle, and the rejection reported to us in the manufacturer's normal 
in-use testing reports. We will provide additional guidance on the 
conditions that must be satisfied to reject a vehicle for this purpose.
    We expect that concerns about the suitability of portable testing 
will continue to diminish as portable emissions measurement systems 
evolve into more compact, durable, user-friendly devices.

C. Phase 1 Testing Scheme

1. Focus of Initial Testing
    The first phase of testing, Phase 1, is intended to quickly screen 
a designated heavy-duty diesel engine family for conformity with the 
applicable NTE standards. If enough of the engines tested from the 
family pass the initial screening, no additional testing of that family 
is required under the in-use testing program in that year. If the early 
test results from Phase 1 indicate a potential nonconformity, then 
several more vehicles must be tested to generate additional information 
regarding the significance of any potential problem, or whether more 
testing in the next phase of the program, Phase 2, is needed to further 
evaluate the emissions performance of that engine family.
2. Engine Family Evaluation Criteria and Outcomes
    For Phase 1 testing, a manufacturer must test a minimum of five and 
a maximum of 10 different vehicles within a designated engine family. 
The exact number of vehicles depends on how many of the tests exceed a 
specified numerical emissions limit, or the vehicle pass criteria, not 
to be confused with the proper maintenance and use criteria (see 
section II. E. of this preamble for a description of the vehicle pass 
criteria). Requiring up to 10 vehicle tests will provide sufficient 
information for us to decide if further testing or other information is 
needed to better evaluate a potential nonconformity, or if some form of 
remedial action may be warranted. This level of testing will provide a 
quick indication of an engine family's emissions compliance without 
being overly burdensome to engine manufacturers. Our multi-step engine 
family evaluation criteria and the outcomes associated with how many 
vehicles pass the in-use testing requirements at various levels within 
the testing hierarchy are described below.
    A manufacturer will initiate Phase 1 by testing 5 vehicles. If all 
five satisfy the vehicle pass criteria (i.e., 5 out of 5 pass), testing 
stops and no other action is required of the manufacturer for that 
diesel engine family under the program for that year. If only one of 
the initial test vehicles fails the vehicle pass criteria, the 
manufacturer will test another vehicle. The manufacturer may stop 
testing if the sixth vehicle satisfies the vehicle pass criteria (i.e., 
5 out of 6 pass). In the event that neither of the above conditions are 
met (i.e., 4 or fewer out of 6 pass), the manufacturer must test a 
total of 10 vehicles.
    Various outcomes are possible based on the observed number of 
vehicle passes or failures from the Phase 1 testing, as well as other 
supplemental information. If all four of the additional test vehicles 
met the vehicle pass criteria and only two of the original six test 
vehicles exceeded the criteria (i.e., 8 out of 10 pass), testing stops 
and no other action is required of the manufacturer for that diesel 
engine family under the program for that year. When six or seven of the 
10 test vehicles satisfy the vehicle pass criteria (i.e., 6 or 7 out of 
10 pass), the manufacturer must join EPA in follow-up discussions to 
determine whether any further testing, investigations, data 
submissions, or other actions may be warranted. In such a case, three 
outcomes are possible. First, we may ultimately decide not to take 
further action if no significant nonconformity is indicated after a 
thorough evaluation of the causes or conditions that caused vehicles in 
the engine family to fail the vehicle pass criteria, and a review of 
any other supplemental information obtained separately by EPA or 
submitted by the manufacturer shows that no significant nonconformity 
exists. Testing would then stop and no other action is required of the 
manufacturer for that diesel engine family under the program for that 
year. Second, we may seek some form of remedial action from the 
manufacturer based on our evaluation of the Phase 1 test results and 
review of other supplemental information. Third, and finally, the 
engine manufacturer may undertake Phase 2 testing, if both EPA and the 
manufacturer agree this is the best course of action. Of course, a 
manufacturer may always voluntarily conduct Phase 2 testing.
    In the event that fewer than six test vehicles comply with the 
vehicle pass criteria (i.e., 5 or fewer out of 10 pass), the 
manufacturer must consult with us just as when six or seven out of 10 
pass as described above. Once again, we may decide not to take further 
action if no significant nonconformity is indicated. If a possible 
nonconformity is indicated, the consultation may lead us to mandate 
Phase 2 testing even if the manufacturer does not voluntarily elect to 
do so. In situations where a significant nonconformity is observed 
during Phase 1 testing, we may order a recall action for the diesel 
engine family in question if the manufacturer does not voluntarily 
initiate an acceptable remedial action.

D. Phase 2 Testing Scheme

1. Initiation and Focus of Additional Testing
    The primary purpose of Phase 2 test program is to gain further 
information regarding the extent to which, and under what conditions, 
the vehicles from the designated engine family are failing to pass the 
vehicle pass criteria. If appropriate, a manufacturer's testing may be 
focused on certain test conditions or a subclass of engines within the 
designated heavy-duty diesel engine family as outlined below. As 
described previously, EPA and the manufacturer may agree that it is 
appropriate to initiate Phase 2 testing if six or seven of the 10 test 
vehicles in Phase 1 satisfy the vehicle pass criteria. Phase 2 testing 
may also be mandated by us in the event that only five or fewer of the 
test vehicles in Phase 1 meet the

[[Page 34602]]

vehicle pass criteria. (See section II. C. for additional information 
regarding the conditions under which Phase 2 may be initiated.)
2. Number of Engines and Test Conditions
    We may require a manufacturer to test up to 10 vehicles from the 
designated heavy-duty diesel engine family under Phase 2. We may, at 
our discretion, require the testing of fewer than 10 vehicles. A pass/
fail determination for each vehicle will be made by comparing its 
measured emissions to the same vehicle pass criteria used in Phase 1. 
Testing up to 10 additional vehicles under this phase of the program 
will provide valuable information regarding whether the engine family 
conforms with the applicable requirements.
    We may direct a manufacturer to test one or more specific engine 
and emission control or power configurations (i.e., subclasses) within 
the designated engine family. Additionally, we may specify certain 
driving routes or other driving conditions (e.g., temperatures, 
altitudes, geographic conditions, or time of year). As already 
discussed, the purpose of these additional specifications is to better 
understand the extent to which, and under what conditions, the vehicles 
in the engines family are failing to pass the vehicle pass criteria. 
Therefore, the specifications would be based on the Phase 1 test 
conditions that indicated a potential nonconformity.
    We requested comment on whether EPA should similarly be allowed to 
direct a manufacturer to test specific engine configurations, test 
routes, and driving conditions for Phase 1 testing. We are not adopting 
that requirement based on our review of adverse comments we received 
from engine manufacturers. The comment and our response is contained in 
section II. J. of this preamble.

E. Vehicle Pass Criteria

    Generally, the vehicle pass criteria require measuring the 
emissions from the test engine each time it operates for 30 seconds or 
more in the NTE control area. The NTE control area is a defined range 
of engine operating conditions that are subject to the NTE emission 
standards (see section I. C. 1. of this preamble for more information 
on the NTE control area). Each excursion into the NTE control area for 
thirty or more seconds is called an NTE sampling event. The 30 second 
minimum is intended to moderate the influence of short-duration, high 
intensity emission spikes that do not have a significant bearing on 
overall, real-world emissions in the compliance determination. The 
average emission level of the NTE sampling event for each regulated 
pollutant is then compared to its corresponding NTE emission threshold. 
The NTE emission threshold is the sum of the applicable NTE standard, 
any in-use compliance margin already allowed by the regulations, and 
the new in-use measurement margin allowance. The vehicle pass criteria 
then require a comparison of the number of NTE sampling events for an 
individual pollutant that were below the respective NTE threshold to 
all of the sampling events from the test for that same pollutant. The 
NTE threshold is further described in section II. F. of this preamble. 
Also, for the first three years of the program, no sampling event may 
be higher than a specific maximum emission limit. The maximum emission 
limit for these engine families is described below.
    More specifically, all valid NTE sampling events for a pollutant 
must be used in the vehicle pass determination. A valid NTE event is 
any sample that meets the 30 second minimum period described above, 
excluding any engine operation that is exempt from the NTE standards 
under the existing regulations. NTE carve-out provisions may either 
exclude certain operating points from the NTE engine control area or 
exempt engines from the NTE standards when operating in defined regions 
of the NTE engine control area. Currently, an engine may also be 
allowed to temporarily exceed the NTE standards under certain limited 
circumstances under the NTE deficiency provisions.\9\ If 90 percent of 
the valid NTE samples on a time-weighted basis for a regulated 
pollutant are no greater than the applicable NTE threshold, then the 
test engine meets the vehicle pass criteria for that particular 
pollutant.
---------------------------------------------------------------------------

    \9\ For more information on NTE control area limits and 
exclusions, see 65 FR 59912, 59914 (October 6, 2000), and 66 FR 5040 
(January 18, 2001).
---------------------------------------------------------------------------

    However, model year 2007 through 2009 engines must meet certain 
additional requirements. For these years, 100 percent of the valid NTE 
samples for any regulated pollutant must also be less than two times 
(2X) the applicable NTE threshold, except when the engine is certified 
to a Family Emission Limit (FEL) for NOX of 0.50 gram per 
brake horsepower-hour (g/bhp-hr) or less. In this case, 100 percent of 
the valid NTE NOX samples must be less than two times the 
NTE threshold or less than 2.00 g/bhp-hr, whichever is numerically 
greater. While operation in the area of an approved deficiency or 
carve-out is excluded from being a valid NTE event for the purposes of 
this in-use testing program, manufacturers must still employ 
appropriate emissions control during operation in these regions as 
required by the prohibition against defeat devices. For any operation 
which occurs within the area of an approved NTE deficiency, we will 
compare the measured emissions results to the emissions estimates the 
manufacturer provided for that deficiency at the time of certification 
so we can determine whether the deficiency requirements have been met.
    The 90 percent criterion should provide a good indicator of 
compliance with the applicable emission standard, while at the same 
time allowing for certain emissions behavior that may be very 
infrequent or unusual in nature and, therefore, atypical of overall in-
use operation. We have fashioned the additional maximum NTE criteria 
for 2007-2009 model year engines because we believe it appropriately 
reflects the capability of current control technology when robustly 
designed and properly maintained. We do not envision any situation 
where the current technology could not be designed to avoid emissions 
above these maximum criteria, even in the atypical situations mentioned 
above. EPA will evaluate the need for, and level of, any such NTE 
maximum criteria for 2010 and later model year heavy-duty diesel 
vehicles based, in part, on data from the proposed in-use test program, 
the capability of technology used to comply with the 2010 model year 
requirements, and other relevant test information. If we decide that 
such criteria are appropriate based on this review, any new 
requirements will be established in a rulemaking action. If we take no 
action, the maximum NTE criteria will cease to exist after the 2009 
model year.
    We are adopting the following multi-part methodology for 
determining if the engine complies with the 90 percent vehicle pass 
criterion for each regulated pollutant. First, find the average g/bhp-
hr emission level for each valid NTE sample for a specific pollutant by 
dividing the total mass of measured emissions (e.g., grams) by the 
amount of work performed during the NTE event (e.g., brake horsepower-
hour). (Note that this step is also used to determine compliance with 
the maximum NTE criteria for 2007-2009 model year engines as described 
above.) Second, determine for each valid NTE sampling event, whether 
the average emission level is less than or equal to the NTE threshold 
for that same pollutant. Third, calculate a time-weighted vehicle pass 
ratio for the pollutant, or the number of valid NTE sampling events 
that meet the

[[Page 34603]]

applicable NTE threshold compared to the total number of valid NTE 
sampling events, weighted by the time of each valid NTE event. To do 
this, begin by summing the time from each valid NTE sampling event 
where the average emission level for each pollutant is no greater than 
the NTE threshold for that pollutant, and then divide this value by the 
sum of the engine operating time from all valid NTE samples. The 
resulting value is the vehicle pass ratio for that pollutant and test. 
However, if any single valid NTE sampling event exceeds 600 seconds or 
10 times the length of the shortest valid NTE event, the time 
contribution for that event must be limited to the smaller of 600 
seconds or 10 times the shortest event for the above calculation. These 
conditions on the maximum allowable duration for any single NTE event 
are intended to prevent a small number of very long sampling events 
from inappropriately overwhelming the time-weighted results.
    A vehicle must meet the vehicle pass criteria for every individual 
pollutant in order for the vehicle to ``pass'' the test under the terms 
of the in-use testing program. Stated differently, failing the vehicle 
pass criteria, even for a single pollutant, counts as a vehicle failure 
for that particular test.
    We want to clarify that the vehicle pass criteria used for the 
manufacturer-run, in-use testing program do not correspond specifically 
to the criteria for showing compliance to the NTE standards. That is, 
the fact that a vehicle meets the vehicle pass criteria under this 
program does not mean that the vehicle passes the NTE standards, or 
that the engine family is in full compliance with the standards, and 
the use of these criteria to show a vehicle ``pass'' in this program 
does not indicate that the criteria would be appropriate for NTE 
testing in other contexts.
    The vehicle pass criteria, along with the engine family evaluation 
criteria of the Phase 1 and Phase 2 test schemes (described later), are 
designed to help make the best use of manufacturers' and EPA's 
resources in determining what further action is appropriate regarding 
that engine family. Therefore, the vehicle pass criteria, the 
definition of a valid NTE sampling event, the criteria for moving from 
Phase 1 to Phase 2, and all others aspects of the in-use testing 
program are solely for purposes of this manufacturer run, in-use test 
program and are not intended to revise, change, or interpret the NTE 
standards, the NTE test procedures, or to define compliance with the 
standards.

F. NTE Threshold Specification

    The numerical value of the NTE threshold is defined as the 
applicable NTE standard, including any compliance margin already built 
into the standard for in-use testing, in addition to a new margin to 
account for the in-use measurement accuracy of the portable emission 
measurement systems. Therefore, these margins are added to the 
applicable standard or FEL to determine the numerical in-use compliance 
limit (i.e., NTE threshold).
1. Not-to-Exceed Standards
    NTE standards applicable to model year 2007 and later heavy-duty 
diesel engines apply to the exhaust emissions of non-methane 
hydrocarbons (NMHC), carbon monoxide (CO), particulate matter (PM) and 
oxides of nitrogen (NOX) from these engines. The levels of 
the NTE standards for these pollutants are determined by applying a 
multiplier to the applicable FTP standard. The multiplier varies by 
pollutant and certification level, but it is generally either 1.25 
times the FTP standard or 1.50 times the FTP standard. See 40 CFR 
86.007-11(a)(4). For 2002-2006 model year engines tested under the 
pilot program, the applicable NTE limit used to develop the NTE 
threshold is 1.25 the FTP standard for that model year.
    The FTP standards for 2002 and 2003 model year heavy-duty diesel 
engines are contained in 40 CFR 86.099-11, except that those engine 
families subject to NTE requirements under the Consent Decrees would 
use an NTE threshold based on the FTP levels found in the appropriate 
Consent Decree. The standards for 2004 to 2006 model year heavy-duty 
diesel engines are contained in 40 CFR 86.004-11. Those for 2007 and 
later model years are shown in 40 CFR 86.007-11.
2. Existing In-Use Compliance Margins
    We previously established compliance margins for in-use 
NOX and PM emissions testing of 2007 to 2010 model year 
heavy-duty diesel engines. For NOX, the margin varies by 
mileage from 0.10 to 0.20 g/bhp-hr for engines certified to an FEL no 
higher than 1.3 g/bhp-hr. For PM, the margin is 0.01 g/bhp-hr. (See 40 
CFR 86.007-11(h) for more details.)
3. New Measurement Margins for Portable Measurement Systems.
    We are including new ``accuracy margins'' in the calculation of the 
emission thresholds for this program. The allowances are primarily 
designed to account for any differences between the accuracy of the 
portable emission measurement instruments for use on a vehicle and the 
accuracy of those available for use in a laboratory. The allowance also 
takes into account the different way in which emissions are calculated 
in a laboratory versus in the field. Because of the continuing 
uncertainty regarding the specific accuracy of development for portable 
measurement systems (See section II. L.), we have chosen to adopt an 
interim set of accuracy margins at this time. These margins will be 
used only in the pilot program. As explained below, we are developing 
more precise accuracy margins for use in the subsequent fully 
enforceable in-use testing program.
    a. Pilot Program Accuracy Margins. During the pilot program years 
that precede the fully enforceable program, manufacturers will use 
interim margins that we believe represent an upper bound of the 
possible instrumentation variability based on our experience with 
portable and laboratory measurement systems. The pilot program accuracy 
margins are: NMHC, 0.17 grams per brake horsepower-hour (g/bhp-hr); CO, 
0.60 g/bhp-hr; NOX, 0.5 g/bhp-hr; and PM, 0.10 g/bhp-hr.
    b. Final Program Accuracy Margins. The margins for the fully 
enforceable program, i.e., 2007 for gaseous pollutants and 2008 for PM, 
are being jointly developed through a comprehensive research, 
development, and demonstration program. The cooperative program is 
described in a Memorandum of Agreement (MOA) among EPA, CARB, and the 
engine manufacturers.\10\ The purpose of the MOA is to specify: (1) A 
detailed roadmap for developing data-driven margins based on a sound 
engine and vehicle test plans; (2) the respective roles and 
responsibilities of each party; (3) the exact statistically-based 
algorithms for calculating the data-driven margins; (4) how the final 
margins can be incorporated into the in-use testing regulations; and 
(5) the consequences of failing to complete the cooperative program in 
time to start either the gaseous or PM fully enforceable testing 
program as adopted in today's action. See section II. N. of this 
preamble for a more complete description of the MOA.
---------------------------------------------------------------------------

    \10\ See ``Memorandum of Agreement, Program to Develop Emission 
Measurement Accuracy Margins for Heavy-Duty In-Use Testing,'' dated 
May XX, 2005. A copy of the memorandum is contained in the public 
docket for this rule and at the EPA/OTAQ Web site (http://www.epa.gov/otaq/hd-hwy.htm).
---------------------------------------------------------------------------

    As described at the beginning of this section, we chose the 
additive approach for incorporating the new portable measurement system 
accuracy margins into the NTE thresholds. We did this to

[[Page 34604]]

encourage instrument manufacturers to develop more accurate and 
repeatable portable measurement instruments in the future. A fixed 
allowance creates the same situation that already exists for laboratory 
measurement instruments, which encourages more accurate and repeatable 
instruments. That is, with no allowance or a fixed allowance, a more 
accurate and repeatable instrument will allow engine manufacturers to 
allocate a smaller fraction of their compliance margin to instrument 
error. We will revisit this issue in the future to determine if the 
final margins determined through the comprehensive program discussed 
above should be reduced or eliminated based on technical advances in 
these devices. To this end, we intend to adjust or phase-out such a 
margin through future rulemaking based upon improvements to the 
measurement equipment. We intend, however, that no future action to 
revise the final margins discussed above would take effect prior to 
2010. The adjustment or phase-out would apply to any engine tested 
after such a rule became effective.

G. Considerations in Deciding on Remedial Action

    In determining whether to pursue some sort of remedial action 
following Phase 1 and Phase 2 testing, we will consider supplemental 
information obtained separately by us, or submitted by the engine 
manufacturer. This information could include emissions data from 
additional tests performed with onboard portable emissions measurement 
devices, as well as from testing conducted using engine dynamometers or 
chassis dynamometers. The information may include an evaluation of, 
among other things: The margin by which any exceedence was above the 
NTE threshold; the number of engines that showed exceedences; the 
frequency and duration of any exceedences as compared with the 
aggregate amount of time that all of the test vehicles were operated 
within the NTE zone; the emissions of the test vehicles over the entire 
test route, including average(s); the projected emissions impact of the 
exceedences; and the relationship of the exceedences at issue to the 
engine family's ability to comply with the applicable standards or 
FELs. We will also consider any other data or factors relevant to 
determining whether to pursue some form of remedial action.

H. Quantity of Data Collected

    The minimum time for data collection from a test vehicle is one 
full shift (work) day of operation, provided that each test vehicle 
operates in non-idle modes for at least 3 hours during a typical shift 
day. Prior to the commencement of either Phase 1 or Phase 2 in-use 
testing, the manufacturer will screen-out from Phase 1 testing any 
vehicle that the manufacturer reasonably determines is unlikely to 
operate in non-idle modes for at least 3 hours over a full shift.
    In the event that a selected test vehicle does not operate in non-
idle modes for at least 3 hours over the full shift day, we are 
requiring that the vehicle must be tested over a second full shift day 
of operation. Testing shall not be required beyond the second full 
shift day even if that second day of testing also fails to yield, in 
the aggregate, 3 hours of vehicle operation in non-idle modes. After 
the second day of testing, the valid NTE sampling events will be 
evaluated according to the previously outlined criteria, even if less 
than 3 hours of non-idle data is collected. In the event that no valid 
NTE sampling events are recorded from a selected test vehicle, that 
vehicle will be deemed to have satisfied the vehicle pass/fail criteria 
for the purposes of this in-use testing program. At their option, 
manufacturers may conduct in-use testing for a longer duration.
    While the minimum data collection requirement described above 
applies to both the pilot and fully enforceable programs, an evaluation 
of in-use test data prior to 2007 could change the final value for the 
data collection period. During the pilot program, we will perform a 
statistical analysis, in collaboration with EMA, of the available in-
use testing data, particularly the data generated under the proposed 
pilot program described below, to determine the necessary parameters of 
the test regime. The end result could be either a longer or a shorter 
period of data collection, or other revisions to the in-use NTE testing 
program. We will, if appropriate, amend the regulations based on the 
outcome of this analysis.

I. Screening, Adjustment, and Mileage of Test Vehicles

    To help ensure that testing is conducted on a diverse sample of 
``qualified'' vehicles, our proposal identified a number of general 
pre-selection criteria for prospective test vehicles within a 
designated engine family. First, test vehicles must be obtained from at 
least two sources. We envision the most common source of engine will be 
fleet operators, but could also include independent operators. As 
stated previously, we believe manufacturers will be able to leverage 
existing relationships with its customers or use this program as an 
opportunity to strengthen those relationships. Second, manufacturers 
must screen each selected vehicle for proper use and maintenance and 
reject those vehicles which have not been properly maintained and used. 
Third, prospective test vehicles must be screened to identify those 
that are reasonably likely to operate in non-idle modes for at least 3 
hours over the course of a full shift day (see section II. H. of this 
preamble for more on the non-idle and shift day requirements). Fourth, 
engines or critical vehicle systems that have been tampered with, 
rebuilt, or subjected to major repairs that could affect emissions, 
will not be used in testing. Fifth, test engines must have their 
adjustable parameters set to the specifications contained in the 
vehicle/engine maintenance manual (i.e., set to spec). Sixth, 
manufacturers must establish appropriate means to ensure that test 
vehicles are operated only on diesel fuels meeting the requisite 
specifications for the model year in which they were emissions 
certified. Seventh, and finally, no prospective test vehicles may be 
rejected because of high mileage, except for those whose engines that 
exceed their regulatory useful life.
    We proposed that each manufacturer submit a general plan describing 
how they would identify, locate, and screen vehicle for in-use testing. 
The general plan was intended to cover all engine families selected for 
testing by EPA. The plan was to indicate whether the procurement and 
screening method may result in an emphasis on testing engines from a 
particular type of driving route or from a particular geographic area. 
The plan needed to identify the business relationships, such as with 
vehicle manufacturers or fleet operators, that would be used to recruit 
vehicles. The plan was to describe the methods that will be used to 
gather available information about whether vehicles and engines meet 
the seven general vehicle criteria described above, including any forms 
or procedures that will be used. Finally, the plan would cover 
situations not specifically addressed by the above seven cases. For 
example, how the presence of an onboard diagnostic (OBD) system trouble 
code or an illuminated malfunction indicator lamp (MIL) would be 
treated in the test program. Deviations from the general plan would 
need to be submitted to EPA for evaluation.
    The engine manufacturers commented adversely on the mandatory 
nature of the general plan. They stated that the general plan 
requirements would unacceptably increase the burden of the overall test 
program by adding multiple

[[Page 34605]]

layers of costs, delays, and complexities. Further, they claimed that 
the requirement is not consistent with the ``screening'' nature of the 
Phase 1 testing as described in the settlement agreement. Manufacturers 
suggested that a more reasonable approach for dealing with this issue, 
as described in the preamble for the proposal, is for EPA and the 
engine manufacturers to work together to develop appropriately detailed 
guidance documents relating to recruitment, screening, and preparation 
of vehicles for testing. They also commented that if the general plan 
requirements were retained, EPA should specify its review time for plan 
approval.
    We agree that it will likely be more efficient to obtain the 
information contained in the general plan through guidance rather than 
specific requirements in the regulations. We are currently developing 
the guidance with help from CARB and the engine manufacturers. The 
proposed general plan criteria, as well as other items, are included in 
the guidance. It also includes a template for manufacturers to submit 
the information suggested in the general plan. The manufacturers will 
not be required by the guidance to provide a general plan but if they 
do so, we would expect the criteria in the guidance to be followed.
    We continue to feel that the information contained in the 
voluntarily submitted general plan will be valuable to us in proving a 
greater understanding of how the manufacturers conduct their testing 
programs and an increased confidence in the test results. Without this 
information, we will feel compelled to perform an increased level of 
our own in-use testing to validate the manufacturer's test results. We 
have reduced the potential burden associated with the voluntary 
submittal by making the plan sufficiently general to cover multiple 
engine families. We now envision an annual or maybe even a one-time 
submission of the general plan with manufacturers only highlighting 
deviations from the plan for a given engine family. The aforementioned 
template will accommodate a discussion of any deviations.
    In response to comments, we have also identified protocols 
regarding the use of appropriate diesel fuels or biodiesel fuel blends 
in test vehicles and addressing vehicles with onboard diagnostic system 
(OBD) trouble codes or illuminated malfunction indicator lamps (MIL).
    For test fuels, we proposed that manufacturers must establish 
appropriate means to ensure that test vehicles are operated only on 
diesel fuels meeting the requisite specifications for the model year in 
which they were emissions certified. Engine manufacturers commented 
that EPA should provide a mechanism or approach to ensure no vehicle 
failures were due to bad fuel. Specifically, they requested that a real 
pre-testing method of ensuring that a vehicle has been operated only on 
proper diesel fuels must be developed and integrated into the in-use 
testing program to avoid improper and wasteful testing. The 
manufacturers also commented that the proposed provision would require 
testing to be performed using fuel meeting the specifications for 
certification fuel. Requirements to find and ensure the use of such 
fuel will be overly burdensome. Finally, they recommended that the test 
fuel provision be modified to specify that diesel fuel consistent with 
the engine manufacturer's recommendations be used for testing. This was 
a special concern related to the use of certain biodiesel fuel blends.
    From the comments it is clear that engine manufacturers and EPA 
share the same goals regarding the use of test fuels that are 
appropriate for in-use testing, e.g., they are representative of 
commercially available in-use fuels and a reasonable method be 
identified to avoid wasteful testing on inappropriate fuels. After 
further discussions with CARB and engine manufacturers on this issue, 
we are adopting the following approach.
    A prospective test vehicle's fuel tank(s) may be drained and 
refilled with fuel conforming to the ASTM D975 specifications prior to 
conducting any test. Manufacturers may not provide special fuel for in-
use emissions testing. If fuel is needed before initiating or during an 
in-use test, it must be procured from a local retail establishment near 
the site of vehicle procurement or screening, or along the test route. 
Alternatively, the fuel may be drawn from a central fueling source 
provided that the fuel used is representative of that which is 
commercially available in the area where the vehicle is operated. If 
the manufacturer can document that owner/operator of the prospective 
test vehicle has an established pattern of using one or more specific 
fuel additives and the fuel treatment is not prohibited in the 
vehicle's owner or operator manual, the manufacturer may continue to 
add that same fuel treatment for in-use testing. Also, the engine 
manufacturer may take pre-test and post-test fuel samples from 
recruited vehicles to ensure that appropriate fuel was used during in-
use emissions testing. All fuel test results must be reported to EPA.
    Engine manufacturers have indicated a special concern with the use 
of biodiesel fuel blends in prospective test vehicles. We want to make 
it clear that the past use of biodiesel fuels is not grounds for 
automatically rejecting the vehicle from the test program. Biodiesel-
fueled vehicles are acceptable if they use any biodiesel fuel blend 
(e.g., biodiesel blends not in excess of B5) that is either expressly 
allowed or not otherwise indicated as an unacceptable fuel in the 
vehicle's owner or operator manual. A vehicle recruited into the 
program with a biodiesel fuel blend that is either expressly allowed or 
not otherwise indicated as an unacceptable fuel in the vehicle's owner 
or operator manual, may not be rejected from testing. Of course, 
vehicles using biodiesel fuel blends may have their fuel tank(s) 
drained and refilled with ASTM D975 compliant fuel or an acceptable 
biodiesel fuel prior to testing. The use of fuel additives is also 
allowed as described above.
    Finally, if a test vehicle fails the vehicle pass criteria and the 
manufacturer can prove that a non-compliant ASTM diesel fuel or 
prohibited biodiesel fuel blend was used at any time during the in-use 
emissions test, that particular test may be voided. In this case, the 
vehicle will be treated as described above.
    Turning to the OBD trouble codes and MILs, we proposed to prohibit 
manufacturers, as a general rule, from excluding vehicles from in-use 
testing if the vehicle had an OBD trouble code or MIL illuminated. 
Further, we proposed that manufacturers could not, as a general matter, 
remedy the cause of the trouble code or MIL illumination prior to or 
during in-use testing. However, the existence of these codes or lights 
during the screening process may indicate that the vehicle has been 
poorly maintained, tampered with, or improperly fueled. In these cases 
the manufacturer could request that the vehicle be rejected from the 
program. If a trouble code is set or malfunction light was displayed 
after the vehicle has been accepted into the program, this also would 
not be automatic grounds for eliminating a vehicle or aborting a test 
once it has begun. Here the manufacturer could either test the vehicle 
with the code or ask for approval to remedy the cause of the code if it 
is maintenance related. We provided a number of examples illustrating 
specific occurrences of OBD codes or MILs and the likely disposition of 
those vehicles relative to the testing requirements.

[[Page 34606]]

    The engine manufacturers commented that testing with MILs or codes 
represents abnormal operation because owners of heavy-duty vehicles 
attend to these problems promptly in order to protect their business 
operations. Hence, they argued, that it does not make sense to require 
testing of vehicles with these conditions unremedied and it is 
inconsistent with the settlement document that calls for testing 
vehicles during their ``normal operations.'' The manufacturers also 
stated that there is no comprehensive OBD program aimed at flagging 
emission exceedences or specific flaws in an engine's emission control 
system. Therefore, they believed it is unfair to presume that an 
activated MIL or trouble code necessarily would signify an emissions-
related issue. Finally, manufacturers claimed that having to ask EPA 
for permission to reject or repair a vehicle would cause delays in 
conducting the program and be unnecessarily expensive.
    Although there is currently no federal OBD requirement for heavy-
duty diesel engines, EPA is in the early stages of developing such a 
requirement. The heavy-duty in-use testing program needs to be designed 
to accommodate the expected future OBD regulations. Further, 
manufacturers currently use diagnostic routines systems to varying 
degrees to assist service technicians in the repair of today's engines. 
To the extent those diagnostic routines identify potential problems 
with the emissions control system, it is appropriate for that 
information to be considered in the in-use test program, even if the 
OBD system is not designed to flag emission exceedences. At a minimum, 
even today's OBD systems can potentially identify flaws in an engine's 
emission control system that could cause an emissions exceedence. We 
continue to believe that OBD information can potentially be valuable in 
identifying potential in-use emissions exceedences and understanding 
their cause.
    As in the proposal, EPA will require manufacturers to supply known 
OBD information both with regard to the history of the vehicles and 
their performance once accepted in to the manufacturer-run in-use 
testing program. This information is important in that it may indicate 
emissions-related problems relevant to whether the engines have been 
properly designed to meet emission standards for the useful life of the 
engine and whether the engines are in fact meeting such standards 
during the useful life of the engine.
    However, EPA agrees with the comment that owners of heavy-duty 
vehicles are instructed and are likely to attend to OBD related 
problems promptly. Therefore, manufacturers will not be required to 
test vehicles with a MIL illuminated or a trouble code set. We believe 
it is more appropriate to review emissions-related concerns identified 
by the OBD system without requiring manufacturers to use such vehicles 
in the in-use testing program, and the information that we receive from 
manufacturers will aid in this review. At their discretion, a 
manufacturer may generally test the vehicle with the MIL illuminated or 
trouble code stored, repair the vehicle and then test it (without EPA 
approval), or reject the vehicle from the test program as follows:
    1. If a vehicle is received into the program and the length of MIL 
illumination or trouble code storage is consistent with proper 
maintenance and use, then the vehicle must be tested as received or 
repaired prior to testing. If the vehicle is repaired, the manufacturer 
must report the repair and the associated MIL illumination or trouble 
code to EPA;
    2. If the vehicle is received into the program and the length of 
MIL illumination or trouble code storage is inconsistent with proper 
maintenance and use, the manufacturer has three options. First, test 
the vehicle as received. Second, repair the vehicle prior to testing 
and report the repair and associated MIL illumination or trouble code 
to EPA. Third, reject the vehicle from the test program and replace it 
with another vehicle. The manufacturer must report the repaired or 
rejected vehicle and its associated MIL illumination or trouble code to 
EPA; and
    3. If a MIL goes on or a trouble code is set during an in-use test, 
the manufacturer has two options. First, stop the test, repair the 
vehicle, and re-start the testing. In this case, only the portion of 
the full test results without the MIL illuminated or trouble code set 
would be used in the vehicle pass determination. Second, stop the test, 
repair the vehicle, and initiate a new test. In this case, only the 
post-repair test results would be used in the vehicle pass 
determination. Again, any repair, and the associated MIL illumination 
or trouble code must still be reported to EPA.
    We intend to have developed a guidance that addresses a number of 
issues pertaining to vehicle recruitment, screening, maintenance, and 
testing. The document will also provide guidance in identifying the 
activity thresholds for OBD trouble codes and MIL illumination referred 
to above.
    We also received several additional comments related to vehicle 
acceptance, vehicle selection, screening, and maintenance. First, we 
proposed to require that a manufacturer notify us prior to rejecting a 
prospective vehicle from the program for reasons other than failing to 
meet acceptance criteria contained in the general plan. The engine 
manufacturers commented that they should not be required to notify EPA 
that a candidate vehicle has been rejected if the owner decides not to 
make the vehicle available for testing. We agree that our proposal to 
require advanced notification in this instance could be burdensome. We 
have amended the regulations to clarify that no notification is 
required prior to rejecting a vehicle if the owner refuses to 
participate in the program. We have also clarified the regulations to 
require that a manufacturer must document and report the rejection to 
EPA as part of their normal reporting requirements under the program.
    The second comment relates to making sure that the engines in the 
selected test vehicles are dissimilar. We proposed two basic different 
types of requirements to help ensure that the vehicles selected for 
testing within an engine family displayed variations in operating 
regimes and other usage characteristics. First, manufacturers were to 
recruit test vehicles from at least two different sources. Second, 
manufacturers were to submit a general test plan that was designed, in 
part, to identify if there was any bias, i.e., pre-selection, in a 
manufacturer's recruiting program.
    The Pennsylvania Department of Environmental Protection (PDEP) 
asked how we would ensure that a varying sample of engines within an 
engine family were tested. Specifically, they hypothesized that one 
fleet may have 10 vehicles with the same engine family, and that the 
engines may all have been produced on the same day under the same 
conditions. Further, PDEP suggested that it may be tempting for an 
engine manufacturer to test all these very similar engines. Therefore, 
they wondered if EPA had a strategy to ensure that test engines were 
produced at different times and for different fleets.
    The concern expressed by PDEP is unlikely to be encountered since 
manufacturers are required to select vehicles from at least two 
different sources and submit to EPA detailed information on the 
vehicles they select. Further, even though the general plan is now a 
voluntary submission, we expect that manufacturers will normally 
provide this information. This will help ensure the manufacturer test 
programs

[[Page 34607]]

are reasonably diverse in test vehicles and conditions. Finally, EPA 
has the authority to conduct its own in-use testing if it has concerns 
with the representativeness of the manufacturers' test results.
    The third comment regards setting adjustable parameters. We 
proposed that a manufacturer must set any adjustable parameter to the 
midpoint of its adjustable range prior to testing. Engine manufacturers 
asked that the requirement be expanded to allow an adjustment to the 
manufacturer's recommended setting. We agree with the comment and now 
allow an adjustable parameter to be adjusted to the manufacturer's 
recommended setting or the midpoint of its adjustable range prior to 
testing.
    A fourth comment questions whether engine operating controls might 
be illegally recalibrated prior to testing. We proposed that engine 
manufacturers conduct a thorough screening of each engine before making 
any allowable adjustment or maintenance prior to testing. The results 
of this screening were to be reported to EPA. Also, manufacturers were 
required to screen each selected vehicle for proper use and maintenance 
and reject those vehicles which have not been properly maintained and 
used.
    The PDEP commented that the process of implementing supplemental 
test procedures, e.g., the NTE, was developed because engine 
manufacturers programmed their engines to recognize when they were 
being tested by the federal test procedure and when they were traveling 
on the highway. They asked if we had contingencies to stop engine 
manufacturers from re-flashing the vehicle's electronic control module 
in order to pass the screening process.
    Obviously, a manufacturer that ``reflashed'' a vehicle's electronic 
control module during the screening process would not be generating a 
representative sample of emission results which is required when 
deciding whether an engine family is complying with the emissions 
standards. Further, that manufacturer could be modifying the emissions 
control system such that the engine is no longer covered by a 
certificate of conformity. In that situation, an engine could be in 
violation of Section 203 of the Clean Air Act and subject to civil 
penalties. We have the authority to void the certificate of conformity 
for an engine family if the engine manufacturer did not meet its 
obligation under the in-use testing rules. We also require 
manufacturers to report any steps they take to maintain, adjust, 
modify, or repair the vehicle or its engine prior to testing. 
Falsifying the emissions performance of an engine could constitute 
ground for voiding a certificate. A void certificate also results in a 
violation of Section 203 of the Clean Air Act and possible civil 
penalties because any sold engines are no longer covered by a 
certificate of conformity.
    Finally, we do not anticipate manufacturers resorting to such 
practices and expect to physically participate in the manufacturer 
testing programs to some extent, including during vehicle screening and 
maintenance prior to testing. Finally, EPA will continue to conduct 
some level of its own in-use testing to validate the manufacturer's 
test results and gain confidence in their test programs.

J. Test Conditions

    For all Phase 1 testing, we are requiring that test vehicles must 
to be operated over normal driving routes, carrying routine loads 
during normal atmospheric/environmental conditions, with the vehicle's 
normal owner/operator doing the driving. Our intent is to record the 
emissions from the test vehicles as they are used and operated on a 
normal day-to-day basis.
    For Phase 2 testing, we may direct engine manufacturers to use a 
generic or specific test route and other conditions that replicate 
those observed in the Phase 1 testing that indicated a potential 
nonconformity. These other conditions may include but not be limited to 
specifying the State and/or contiguous States in which testing must be 
performed, or specifying the time period (of no less than 3 months in 
duration during which the testing must be performed. (This latter 
condition may also be used to ensure prompt testing of Phase 2 vehicles 
or to ensure testing during periods of particular atmospheric 
conditions.) In deciding to make these elections, we will take into 
account lead time and vehicle availability constraints.
    We requested comment on whether EPA should similarly be allowed to 
direct a manufacturer to test specific engine configurations, test 
routes, and driving conditions for Phase 1 testing when we have 
particular information suggesting that these stipulations may help 
focus testing on areas where EPA has particular emission-related 
concerns. We believed that such an initial focus might not only improve 
the overall effectiveness of the in-use program, but might reduce the 
number of tests a manufacturer may otherwise need to conduct if Phase 2 
testing is conducted for any reason.
    Engine manufacturers commented that Phase 1 testing is meant to 
quickly screen vehicles for NTE compliance. Further, the manufacturers 
argued that specifying detailed test conditions for Phase 1 adds 
unacceptable complexities, time constraints, costs, and vehicle 
recruitment difficulties, and should not be adopted. After reviewing 
the engine manufacturers objections, we are not adopting a ``directed'' 
testing allowance in Phase 1.

K. Reporting Requirements

1. Comprehensive In-Use Testing Reports
    Engine manufacturers will report test data and other relevant 
information to EPA on a regular basis. Specifically, manufacturers must 
send us reports for all engines tested during a calendar year quarter 
no later than 30 days after the quarter ends. Alternatively, 
manufacturers may send us a report for individual engines within 30 
days after testing is completed.
    These reports will be comprehensive in scope. Manufacturers must 
detail all emissions data, engine operating parameters, test 
conditions, test equipment specifications, vehicle and engine 
information generated during the manufacturer test program (e.g., 
information on vehicle maintenance and usage history with reasons for 
rejected vehicles, restorative maintenance performed prior to testing), 
vehicle pass results, etc. Engine operating parameters include all 
information that is electronically sensed, measured, calculated, or 
otherwise stored by the engine's onboard computer. This must include, 
but is not limited to, engine speed, engine torque or brake specific 
fuel consumption, engine coolant temperature, intake manifold 
temperature, intake manifold pressure, and any parameter sensed or 
controlled in order to modulate the emissions control system. 
Manufacturers must also report any parameters used to modulate the 
emissions control system so that we can readily identify operation 
where an approved deficiency or carve-out applies, and the state of the 
engine during that operation.
    Engine manufacturers will follow a standardized, electronic 
reporting format. We are currently developing the exact content and 
form of the reports with CARB and the engine manufacturers. 
Participation by CARB ensured that the reporting requirements are 
nationally consistent when it establishes an in-use NTE testing program 
of its own. The reporting requirements are detailed in the regulatory 
text accompanying today's

[[Page 34608]]

proposed rule. Additional details, including the final reporting 
format, will be published separately by EPA as a guidance document.
    Engine manufacturers commented that our list of proposed data 
requirements was too extensive and overly burdensome. However, they 
acknowledged that the negotiated outline specifies the submission of a 
``* * * comprehensive report * * *.'' The manufacturers also stated 
that the negotiated agreement called for a standardized reporting 
format to be jointly developed by EPA/CARB and the engine 
manufacturers. They noted that the proposed reporting format was not 
developed in the prescribed manner. Finally, they commented that until 
a jointly developed format has been completed, no final rule should be 
promulgated.
    As noted above, we are developing the reporting format with the 
assistance of the engine manufacturers. We have entirely eliminated 
some of the items that we proposed manufacturers report based on their 
comments. These items have generally been moved to the record keeping 
requirements.
    The engine manufacturers also commented that it may be more 
appropriate for manufacturers to submit reports upon the completion of 
Phase 1 or Phase 2 testing for a specific engine family instead of 
submitting reports on a calendar year basis for all engines tested 
during that quarter. They argued that this would consolidate 
information from a single phase of testing into a single report and 
would avoid the illogical inclusion of dissociated information from 
multiple families into the same report. Further, the manufacturers felt 
this would also ensure more timely reporting of information on 
completion of a phase of testing. Accordingly, they asked for the 
option of reporting either on a quarterly basis, as specified in the 
proposal, or 30 days after the completion of a specific phase of 
testing is concluded.
    We envision that manufacturers will conduct engine family 
evaluations concurrently and that reporting in-use testing results on a 
calendar basis will provide the most timely and effective status 
updates of those testing programs. We also expect manufacturer testing 
to be continuous over multiple calendar quarters. A number of 
individual vehicles will likely be tested over that span of calendar 
quarters before a given phase of testing is complete. Waiting until the 
end of a phase of may not provide EPA sufficient opportunity to follow 
the progress of ongoing test programs. Our database will be designed to 
accept test results as they become available and update the database 
records in a logical manner for easy reading.
    As mentioned previously, we are allowing 18 months for the in-use 
testing of any engine family be completed and fully reported to provide 
manufacturers with adequate lead time to properly planning and 
conducting the in-use test program. A manufacturer may request up to 
six addition months to complete and report Phase 2 test results if 
there is a reasonable basis for needing more time. Further, a 
manufacturer may request an additional six month extension. A 
successful request for this added extension will be limited to 
extraordinary circumstances beyond the control of the manufacturer and 
its customers whose vehicles are being tested. The testing and 
reporting period begins from the date EPA officially notifies the 
manufacturer that an engine family has been designated for in-use 
testing.
    Engine manufacturers commented that they were dissatisfied with 
both the requirement to complete all testing of a designated engine 
family within 18 months, and the option to request a six-month 
extension for Phase 2 testing if justifiable. They concluded that it 
may be impossible to meet these deadlines in some cases, although no 
specific examples were provided. Instead, they asked that the provision 
be deleted or modified to allow unlimited extensions where 
circumstances dictate.
    We believe that allowing unlimited extensions seems unnecessary and 
could result in engine families exhausting their useful lives before 
meaningful compliance data is generated. We also think that 18 months 
is sufficient to complete testing under normal circumstances. 
Manufacturers agreed to this in the settlement document, which states 
that data from the testing of a designated heavy-duty on-highway diesel 
engine family will be completed and reported to EPA and CARB within 18 
months from of the designation of that family by EPA/CARB. In the 
proposal, we went even further and acknowledged there may be situations 
where an additional 6 months could be warranted due to unforseen and 
infrequent events. Therefore, we adopted the test and reporting period 
as proposed.
    Nonetheless, we acknowledge that there might be some instances when 
unforseen complications may arise. In order to ensure the test program 
is successfully initiated with minimum burden to manufacturers, we will 
remain open to a request from any manufacturer for additional time 
beyond the 6 month extension. A successful request for this added 
extension will be limited to extraordinary circumstances beyond the 
control of the manufacturer and its customers whose vehicles are being 
tested. The threshold for such consideration is intended to be 
extremely high, and the frequency of such manufacturer requests, much 
less EPA approval, extremely low. In no instance, would the second 
deadline extension exceed 6 months. Finally, to the extent that any 
such additional extensions are needed, we would expect these to become 
non-existent as manufacturers gain experience with the in-use test 
program.
    We are also adopting our proposal that allows us to obtain more 
information from the manufacturer than is specified in the reporting 
requirements if it is needed to evaluate whether an engine family meets 
the in-use testing requirements. Engine manufacturers commented that 
this allowance was an open-ended requirement that was unreasonable and 
unacceptable.
    The allowance for us to request additional information is a general 
requirement common to all of EPA's regulations. There is nothing unique 
about the heavy-duty in-use test program that would diminish the 
important of this requirement. Therefore, we have retained it in the 
final rule.
2. Notification of Individual Vehicle Failures
    We are requiring that manufacturers must ``quickly'' notify us when 
certain individual vehicles fail the vehicle pass criteria. The 
accelerated reporting period for failing vehicles is designed to afford 
EPA the opportunity to participate in the diagnosis of vehicle failures 
and any resulting follow-up activities. Specifically, we are requiring 
such notifications at two different points in the testing scheme. The 
first is when an engine family has experienced three failures in Phase 
1 testing. This is the point where a manufacturer is fully committed to 
testing a total of 10 vehicles. Further, this is the threshold where, 
at the conclusion of Phase 1 testing, a manufacturer must join EPA in 
follow-up discussions to determine whether or not any further testing 
(i.e., Phase 2), investigations, data submissions, or other actions may 
be warranted. We require that a manufacturer notify us by email within 
15 days when the initial review of the test data for a selected engine 
family indicates that a third failure in Phase 1 testing has occurred.

[[Page 34609]]

    The second point is each time a vehicle failure occurs during Phase 
2 testing. In this case, we require a more immediate notification 
because of the increased significance of such failures. These failures 
are significant because of the greater likelihood of a possible 
nonconformance and the possibility that testing needs to be focused on 
specific vehicle configurations, environmental conditions, etc. In this 
phase of the program, we will require that a manufacturer notify us by 
email within 3 days when the initial review of the test data for a 
selected engine family indicates that a vehicle failure has occurred in 
Phase 2 testing.
    In the proposal, we specified a more comprehensive scheme for 
rapidly reporting vehicle failures. Each individual vehicle failure 
needed to be reported to us within 15 days of conducting the emissions 
test. The report was comprehensive in nature. It included detailed 
emissions and engine data from the test in addition to any diagnostic 
results and conclusions. The manufacturers opposed the requirement, 
stating that the provision was unduly burdensome and unnecessary.
    We continue to find that accelerated reporting of vehicle failures 
provides us with an important opportunity to participate in the 
diagnosis of failing vehicles and any resulting follow-up activities. 
This is no different than the opportunity we provide manufacturers in 
our own test programs. In light of the comment, however, we have 
reconsidered how our objective can be achieved while minimizing any 
associated reporting burden. As a result, we eliminated the 
comprehensive nature of the reporting requirement and made the 
requirement a simple notification when a potential failure has been 
observed. We also reduced the frequency of such notifications to the 
two points in the testing scheme as described above. These two points 
in the testing scheme were selected because that is where failures 
clearly become of sufficient interest to us that we may want to have 
the opportunity to participate in the test program.
3. Carve Outs, Deficiencies, or Other NTE Control Area Exclusions
    Depending on the applicable standards, several provisions in the 
existing heavy-duty diesel engine regulations allow a manufacturer to 
temporarily exceed the NTE standards under certain limited 
circumstances, or otherwise exclude defined regions of the NTE engine 
control zone from NTE compliance. (See 65 FR 59912 and 59914 (October 
6, 2000), and 66 FR 5040 (January 18, 2001)). These exceptions are also 
allowed in determining if a vehicle passes the vehicle pass criteria as 
described in section II. E. All such exclusions and associated test 
data must be fully described and submitted to us as part of the 
manufacturer's quarterly or 30-day emissions test result report that is 
required under the terms of the program.
    More specifically, we are requiring that a manufacturer's report 
for each engine tested must describe the parameters that activate and 
de-activate each NTE deficiency as well as the engine load and speed 
points used to define an NTE carve-out tested under the program. This 
information must generally be in a form that can easily be used to 
determine whether a particular deficiency or carve-out was encountered 
when evaluating 1 Hz NTE test results. The information must be in a 
form that can be either loaded directly in EPA's electronic database or 
readily converted by us into the required data input structure.
    For each NTE deficiency, the manufacturer must provide every engine 
and operational parameter(s) used to activate and deactivate the 
deficiency as well as the associated activation and deactivation 
thresholds. If more than one parameter is used to activate or 
deactivate a deficiency, the manufacturer must supply the logic that 
defines how those parameters interact. For any approved carve-out, 
manufacturers must provide the equation or equations that define the 
carve-out region as a function of engine load and speed. The engine 
computer must broadcast at 1 Hz, each parameter used to activate or 
deactivate a deficiency. EPA, CARB, and the engine manufacturers will 
jointly develop a template for submitting the information to EPA and 
CARB. This template will be included in a guidance document on this 
subject.
    We requested comment on whether manufacturers should be required to 
electronically identify when the engine is operating in the area of an 
approved carve-out or deficiency and report that information as a data 
output to the portable emissions measurement systems. Flagging the 
presence of a carve-out or deficiency in such a manner appeared 
feasible as a relatively minor revision to the engine's on-board 
computer software. We envisioned the software changes would be limited 
to manipulating already broadcast or stored parameters. Electronic 
reporting of this information would ease the data analysis for the 
engines tested in the manufacturer-run, in-use testing program, and 
allow ready access to the same type of information for engines that may 
be tested in our own program using portable emission measurement 
systems.
    Manufacturers commented that the requirement was too costly and 
time intensive. They stated that valuable electronic control module 
(ECM) processing capacity would be used just to provide an ``easy'' 
electronic indicator for NTE operation. Manufacturers provided no data 
or other information to support their claim that the requirement was 
``too costly and time intensive.'' Upon further consideration, we 
recognize requiring manufacturers to add the electronic capability to 
flag NTE deficiencies and carve-outs as part of this rulemaking might 
present an unreasonable burden from the perspective of lead-time for 
the 2007 model year, which is less then two calender years away. We 
continue to believe that electronically reporting NTE deficiency and 5 
percent limited testing region flags on a real time basis is necessary 
to improve the efficiency of collecting and analyzing in-use test data. 
EPA believes that the 2010 time frame would provide adequate time for 
manufacturers to begin implementing such an ECM-based reporting 
requirement. We intend to pursue this in a future rulemaking regarding 
onboard diagnostic systems for heavy-duty vehicles.
    Regarding the availability of such information for use in our own 
in-use testing program, we can always request such information from a 
manufacturer in lieu of receiving it as part of the ECM read out. 
However, we want to ensure that these requests receive special handling 
to expedite our testing. We are, therefore, requiring that 
manufacturers provide engine information which clearly identifies the 
parameters defining all NTE deficiencies and parameters defining all 
NTE carve-outs for an engine family and associated power level when 
requested. Further, that the deficiencies and carve outs must be 
reported in sufficient detail for us to determine if a particular 
deficiency or carve-out will be encountered in the emission test data 
from the portable emission-sampling equipment and field-testing 
procedures. Such information is to be provided within 60 days of the 
request from EPA.
4. Incomplete, Invalid, or Voluntary Tests
    We proposed that engine manufacturers must report all results from 
emissions testing, including incomplete tests, invalid tests, and 
additional tests that are voluntarily conducted.

[[Page 34610]]

    The engine manufacturers objected to reporting results from the 
types of tests described above. They stated that such a requirement is 
overly burdensome and intrudes on a manufacturer's right to conduct 
voluntary tests without EPA ``supervision.'' Further, the manufacturers 
also specifically objected to reporting results when Phase 2 testing 
was voluntarily undertaken.
    We continue to believe that the results of incomplete and invalid 
tests can yield valuable information regarding NTE emissions compliance 
and that it is legitimate to have access to this information within the 
context of the in-use program. However, to keep the reporting burden to 
a minimum, we will only require manufacturers to notify us in their 
formal reports when such tests were conducted for a selected engine 
family. Further, manufacturers will simply be required to keep all 
related test data and other relevant information as part of their 
recordkeeping in case we ask for it.
    We disagree with the engine manufacturers suggestion that the 
results of testing should not be reported to EPA when a manufacturer 
voluntarily undertakes Phase 2 testing. In this instance, a 
manufacturer would be conducting the testing as a consequence of the 
Phase 1 test results. This follow-on testing is clearly a logical next 
step in the manufacturer-run, in-use testing program, and the results 
of such testing must be properly reported to EPA.
    Regarding other voluntary tests that a manufacturer may conduct 
outside of the manufacturer-run, in-use testing program, we find that 
it is important for us to be aware when a manufacturer conducts such 
testing. Beyond providing valuable information, we want to prevent a 
situation where voluntary testing might be interpreted as having been 
conducted to screen test vehicles for passing results, which might then 
be submitted to us as valid tests under the in-use program. We do agree 
with the manufacturers, however, to the extend that our proposal could 
be interpreted as too broad and overly burdensome.
    To accommodate these legitimate concerns, we have refined our 
requirements in this area as follows. First, we will limit this 
requirement to voluntary tests conducted on the same engine families 
that are being tested under the in-use test program. Second, we will 
focus the requirement on the period between the time the family is 
first selected for testing, until the final results of all testing for 
that family are reported to us. Third, as described above for invalid 
and incomplete tests, we will only require manufacturers to notify us 
in their formal reports when such tests were conducted for a selected 
engine family. The notification must clearly describe the purpose of 
the voluntary testing and how it is unrelated to the vehicle 
recruitment, screening, and testing conducted under the manufacturer-
run, in-use testing program. Fourth, and finally, manufacturers will 
simply be required to keep all test data and other relevant information 
as part of their recordkeeping in case we ask to review it.

L. Measurement of Emissions

    We are adopting the test procedures in 40 CFR part 1065 subpart J, 
``Field Testing'' for conducting any emissions testing required in this 
program, as well as any other onboard testing required for heavy-duty 
engines under part 86, subpart N. These revised requirements are being 
promulgated as a companion rule to today's final manufacturer-run, in-
use testing rulemaking.
    We proposed to adopt the test procedures in part 1065, subpart J, 
``Field Testing'' for conducting any emissions testing required in the 
in-use testing program, as well as any other onboard testing required 
for heavy-duty engines under part 86, subpart N. In our proposal, we 
noted that changes were being made to the then current version of part 
1065, and that those revisions were being published in a separate 
companion Notice of Proposed Rulemaking (NPRM). The relevant proposed 
test procedures were generally described, and we asked that comments on 
the companion NPRM be directed toward that notice.
    Manufacturers commented that the comment period on the in-use 
testing program be extended to align it with that of the companion test 
procedure proposal. They argued that the field testing provision had 
not yet been published and that this made it impossible to comment in 
total on the proposed in-use testing program. We chose not to extend 
the formal comment period for this rule, but have continued to exchange 
information with affected companies over an extended period up to the 
conclusion of the final rule. Manufacturers were able to provide any 
comments regarding the interaction of the regulations for this rule and 
the rule revising part 1065 during the comment period for that rule. 
There were no comments on that rule that would indicate that the 
effectiveness of this rule will be undermined by the proposals in that 
rule. We have addressed each of the comments submitted, as described 
elsewhere in this document, and in the companion rulemaking to adopt 
changes to the test procedures in 40 CFR part 1065.
1. Pollutants and Other Emissions
    We are requiring the in-use measurement of the following pollutants 
from heavy-duty diesel engines: Non-methane hydrocarbons (NMHC), total 
hydrocarbons (THC), carbon monoxide (CO), oxides of nitrogen 
(NOX), and particulate matter (PM). We are also requiring 
the measurement of carbon dioxide (CO2) and oxygen 
(O2) as a component of test measurement specifications and 
as a means of assuring quality control. Recognizing that experience may 
show that the effectiveness, durability and overall performance of new 
engine technologies and exhaust aftertreatment systems may demonstrate 
that in-use testing for certain pollutants is unnecessary, we will 
consider requests from the engine manufacturers to discontinue 
reporting and/or measurement of one or more pollutants from some or all 
engines based on future test experience.
    In the proposal, we requested comments on requiring the in-use 
measurement of NMHC because it was not explicitly listed in the 
settlement agreement. We noted that the 2007 hydrocarbon standards for 
heavy-duty engines are written in terms of NMHC (or NMHCE) not THC. In 
addition, recent testing indicates that the traditional relationship of 
NMHC to THC in diesel exhaust (typically, NMHC is 98% of THC) is no 
longer applicable when aftertreatment like PM filters are used. 
Therefore, there is less of an exact correlation between THC and NMHC 
emissions and the traditional way of correlating such emissions in our 
regulations could lead to overestimation of NMHC emissions. Finally, 
NMHC can be measured on-vehicle without significant further effort. As 
a result, we believed the measurement of NMHC was justified.
    Engine manufacturers objected to mandatory NMHC measurement. They 
also objected to being required to measure THC from diesel engines with 
catalyzed PM filters, arguing that the emission control technology 
results in negligible hydrocarbon emissions. However, the engine 
manufacturers wanted to have the option of measuring NMHC instead of 
THC if hydrocarbon measurement were required.
    We are requiring the measurement of hydrocarbons in the in-use 
testing program and because NMHC is a regulated emission with an 
associated NTE standard, it must be reported. Commercially available 
portable measurement systems already report NMHC as the difference 
between

[[Page 34611]]

measured THC and methane (CH4) via dual FID/cutter technology. This 
measurement technology already meets all the NMHC requirements in Part 
1065. Additionally, part 1065 provides the flexibility to report NMHC 
as the difference between measured THC and measured methane (CH4), or 
it may be reported as 0.98*THC. Therefore, manufacturers may optionally 
measure THC and report NMHC as 0.98*THC. However, we do not recommend 
this approach given the commercial availability of suitable portable 
technology that would yield a more accurate NMHC measurement.
    Regarding the comment about ``negligible NMHC'' emissions, we 
believe that certain engines and exhaust aftertreatment systems can 
emit NMHC emissions at or above the NTE standard. This is particularly 
possible if the aftertreatment technology uses a hydrocarbon-based 
reducing agent, e.g., diesel fuel, to ``regenerate'' the aftertreatment 
system. Nonetheless, in cases where a manufacturer can demonstrate that 
and engine and aftertreatment system combination negligible NMHC 
emissions, the manufacturer may petition EPA to waive associated 
measurement requirement, as we proposed and are now adopting.
    Engine manufacturers also requested that hydrocarbon measurement 
not be required due to safety concerns with the hydrocarbon fuel used 
by the flame ionization detector (FID) in the portable analyzer to 
measure that pollutant. We have been using a unit produced by one 
manufacturer in our own in-use testing that is approved as safe by the 
Department of Transportation (DOT) for on-vehicle use. We expect that 
other manufacturers either have or will also DOT certify their devices 
for on-board emission measurement. In fact, we would not recommend 
using any portable device that utilizes FID fuel if it is not certified 
in conformance with DOT standards for such testing. Therefore, we 
disagree that the use of FID technology in the in-use test program 
necessarily poses a safety concern.
    Manufacturers also commented that we should issue guidance that 
outlines reasonable conditions and procedures for manufacturers to 
follow in requesting an emission measurement waiver. We do not believe 
that a specific guidance document on this issue is necessary. The basic 
conditions and procedures for requesting an EPA waiver to avoid 
measuring a pollutant is obvious enough. Waivers will be reviewed on a 
case-by-case basis.
2. Portable Emission Measurement Systems--Status and Availability
    Portable emission measurement systems will be used to measure the 
emissions and activity of vehicles tested in this program. Portable 
measurement systems have been under development for a little more than 
ten years. Currently, the status of these devices relative to their 
development and availability is different for gaseous and particulate 
emissions. Studies conducted by EPA, CARB, and the product 
manufacturers have shown that the technologies used in portable systems 
for gaseous emissions have been effective in accurately measuring 
emissions from in-use motor vehicles under the various conditions that 
could be expected in this test program. More specifically, commercial 
portable measurement systems have been available from a number of 
manufacturers since 2002 that measure THC, CO, and NOX 
emissions at the requisite exhaust concentrations associated with 2007 
and later model year NTE standards. In 2004, units were introduced that 
measure NMHC, although some extra work is being instituted to verify 
the accuracy and precision of these new systems. Also, EPA is working 
on a program, with cooperation from ARB and the engine manufacturers, 
under which portable emission measurement systems will undergo 
comprehensive testing, including the identification of data-driven 
``measurement allowances.'' A measurement allowance is an emissions-
specific, brake-specific value that will be added to the NTE standard 
to determine an NTE threshold for the purposes of the manufacturer in-
use testing program. Its purpose is to account for any differences 
between the accuracy of the portable measurement systems in the field 
and the accuracy of laboratory measurement systems in a lab. Additional 
details on this latter program are presented in section II. L. 3.
    The development of portable systems for measuring PM has proven to 
be more challenging than the development of similar systems for 
measuring gaseous emissions. Currently, prototype portable systems for 
measuring PM are available from equipment manufacturers, and we have 
tested them in the laboratory with encouraging results. This 
demonstrates that the overall technology has been identified, although 
more work is needed to demonstrate its accuracy and efficacy in the 
laboratory and in the field for the purposes of the in-use testing 
program. In addition, work is continuing to miniaturize the on-board 
sampling devices and develop suitable exhaust dilution sampling 
techniques and hardware.
    In our proposal, we acknowledged the significance of the 
development effort for PM portable measurement systems, especially with 
regard to being able to start the pilot program in 2005. Manufacturers 
echoed this concern in their comments. Specifically, we stated that if 
PM systems were not going to be available for the 2005 pilot program, 
we would consider delaying the PM requirement until 2006 or 2007, or 
temporarily relaxing the proposed equipment measurement tolerances. 
Consistent with that position, our current assessment of the state of 
portable PM emissions measurement systems has resulted in delaying the 
start of the pilot and fully enforceable programs for PM by one year 
from the dates contained in the proposed rulemaking.
    We believe that the one-year delay for the PM pilot program (i.e., 
2006) will result in the availability of prototype portable devices 
capable of measuring these emissions as required. We also believe that 
the one-year delay for the fully enforceable program (i.e., 2008) will 
result in useable, accurate, and precise portable units in time for use 
in that program. Our position is based on work that EPA, CARB, 
equipment manufacturers, and the engine manufacturers either have 
underway or have committed to performing to resolve the remaining 
development and verification issues, as described below. However, in 
recognition of the remaining uncertainties associated with these 
efforts, we have added a provision to the regulations that would 
suspend the in-use test program as it applies to PM measurement if we 
determine that fundamental technical problems with portable in-use PM 
measurement systems are not resolvable in a reasonable time.
    As noted above, prototype portable units for measuring PM have been 
successfully tested in the laboratory, but further development work is 
needed to resolve some key challenges. The most significant of these 
are: Quantifying or weighing 30-second samples of semi-volatile 
hydrocarbons and dilute sulfuric acid PM at the NTE standard (i.e., 
about 250 nanograms), proportionally diluting a partial flow of raw 
exhaust in order to sample PM at the same conditions as our laboratory 
procedures, and establishing a standard way of evaluating whether or 
not candidate systems actually meet these challenges. The work to 
resolve these remaining issues and to verify portable PM measurement 
technology in terms of

[[Page 34612]]

usability, accuracy and precision, can generally be divided into four 
program areas.
    The first is our ongoing program that takes prototype portable PM 
measurement technology, which equipment manufacturers continue to 
refine, and compare the measurement capability of that hardware with 
current laboratory measurements. In this regard, we have recently 
acquired more sophisticated prototype devices for testing. We are 
evaluating a laboratory-scale quartz crystal microbalance (QCM) versus 
our laboratory PM measurement procedures. This evaluation is intended 
to verify whether or not prototype QCM technology reports PM similarly 
to the laboratory's reported values. We are confident that the QCM is a 
viable technology for the following reasons:
    a. The QCM measures PM by electrostatically depositing mass on the 
QCM, and as PM deposits on the QCM its oscillating frequency changes in 
proportion to the total mass of the deposited PM. Because the QCM 
measures total PM mass directly by inertial acceleration, the QCM 
measures the same physical property; namely total mass, as compared to 
our laboratory filter-based procedure, which measures mass by 
gravitational acceleration (via a PM microbalance).
    b. The design and construction of this technology is of a 
reasonable size and weight, and its power consumption indicates that 
this technology is likely to be sufficiently portable for on-vehicle 
use.
    c. This PM PEMS technology is also specified to allow up to eight 
hours of continuous unattended operation so it will be appropriate for 
the HDIUT program.
    d. Because QCM technology can measure ``nano-gram'' levels of PM, 
we believe that it is sufficiently sensitive to measure 30-second 
samples of PM at the NTE standard. For example, under typical dilution 
conditions in the NTE, 30 seconds of PM at the 2007 NTE standard (0.03 
g/hp-hr) is in the range of 200 to 300 nanograms when sampled at one 
liter per minute, which is the sample rate of the QCM.
    We intend to expand the work described above to include an already 
available portable partial-flow dilution system and a fully portable 
QCM.
    The second is another internal EPA program that we anticipate 
beginning in the near future. In this program we will intend to develop 
techniques to generate ``reference PM'' in order to fully evaluate 
portable measurement systems using particles with similar physical 
characteristics and at the expected PM levels associated with the NTE 
standard and over intervals as short as 30 seconds.
    The third is the PM pilot program. In the pilot, engine 
manufacturers will use best-available portable measurement systems as 
part of their testing. This program will give engine manufacturers an 
opportunity to evaluate the usability of these portable devices. We 
expect that information gained from this pilot program will be helpful 
for both EPA, equipment manufacturers, and engine manufacturers to 
prepare for the 2008 enforceable PM program.
    The fourth is our cooperative research, development, and 
demonstration effort with CARB and the engine manufacturers. Under this 
comprehensive program, portable PM emission measurement systems will be 
rigorously tested and data-driven ``measurement allowances'' will be 
identified. Additional details on this program are presented in section 
II.L.3.
    Based on the development and demonstration programs described 
above, as well as the ongoing work of equipment manufacturers, we 
remain optimistic that portable systems for PM testing will be 
available for the pilot program in 2006 and the fully enforceable in-
use program starting in 2008.
    The technical support document that accompanies today's final 
rulemaking contains more information on the status and development of 
portable emission measurement systems.
    Engine manufacturers had some specific comments regarding the 
availability of portable emission measurement systems. Detroit Diesel 
Corporation commented that EPA failed to recognize that in order to 
begin production of 2007 model year engines with an appropriate level 
of confidence that those engines will meet in-use requirements, the 
availability of in-use measurement equipment will be required long 
before production of those engines begins. Specifically, the company 
referred to the need to conduct field validation of final engine 
calibrations as early as the winter of 2005/2006. Further, that testing 
would require equipment that has the capability for accurate 
measurement at below 1 gram/bhp-hr NOX development targets. 
Therefore, DDC concluded that it is unreasonable to expect that 
equipment being qualified at the 2.5 gram NOX level should 
also be adequate for development of engines at a 1 gram NOX 
level, and even more unreasonable to consider its use for developing at 
levels below the 0.2 gram NOX standard.
    Our assessment shows that portable measurement systems with the 
capability to reliably measure NOX emission at the 2 g/bhp-
hr level have been commercially available since 2002. Given that engine 
manufacturers are likely to certify MY2007-MY2010 engines at around the 
1.1-1.3 g/hp-hr level, the corresponding NTE standard from MY2007-2010 
will be about 2 g/hp-hr, depending upon vehicle mileage and other NTE 
flexibilities. Therefore, manufacturers could have started such field 
validation of final engine calibrations as early as about 2002. In 
fact, in 2003 Detroit Diesel Corporation gave public presentations 
showing how they are already using PEMS to field validate final engine 
calibrations. Therefore, we disagree with the comment in this area.
    Also, as described in the previous section (see section II.L.2.), 
portable units that measure THC and CO have also been available since 
2002. Units capable of measuring NMHC have been available since 2004. 
(Further work is needed on these instruments to determine their 
accuracy and precision, but compliance with the associated NTE standard 
can optionally be demonstrated by measuring THC, as explained in 
section II.L.1. of this preamble.)
    Based on other comments, we acknowledge that compliance with NTE 
standards will require design engineers to better understand their 
engines' emission behavior over a wide range of possible engine 
operation, but we do not feel that access to field-testing systems at 
an early stage of engine development is a prerequisite for the 
successful development of engines that meet the NTE standards. Though 
claims have been made that NTE standards might be interpreted to cover 
a theoretically infinite degree of variability during in-use operation, 
we expect that by evaluating a range of in-use duty cycles a consistent 
level of control for any additional operation may be predicted. This 
evaluation may be conducted solely in a laboratory by making careful 
measurements over a statistically sound sampling plan. Such a 
statistically-based test plan provides reasonable certainty that any 
future emissions from an engine is likely to be within certain bounds. 
This approach is frequently used to ensure reliability of engine parts 
and engine performance even though an engine manufacturer never tests 
such parts or performance over an infinite number of in-use conditions. 
We expect a similar approach to be taken when designing engines to meet 
NTE standards.
    Furthermore, we do not believe that manufacturers will need to test 
an ``infinite'' or inappropriately large number of steady state and 
transient

[[Page 34613]]

combinations with field test equipment. Rather, manufacturers will be 
able to quickly narrow their test programs in the laboratory to focus 
in on those areas of engine operation where emissions come closer to 
exceeding the NTE standards. Engineering experience and logic dictates 
that manufacturers will not expend resources testing areas where 
emissions are well understood and well below the NTE standards. 
Therefore, we expect that manufacturers can developed and demonstrate 
engine calibrations using existing portable measurement systems and 
normal engineering practices.
    In another comment, engine manufacturers stated that the PM 
requirement was infeasible. They noted that verified portable sampling 
systems do not exist at this time. Further, they commented that PM 
emissions should not be included in the program until such time as 
validated, properly field-tested, on-vehicle devices become 
commercially available. Finally, the industry association commented 
that it is uncertain whether any portable measurement system can 
actually measure the same physical quantities as the filter-based 
method that is used in the laboratory, which is the basis for the 
regulatory definition of particulate, but also the underlying 
certification of heavy-duty diesel engines.
    We have accommodated the engine manufacturers concerns with regard 
to the availability of suitable PM measurement equipment in a number of 
ways as described previously in this section. First, we have delayed 
the start of the pilot and fully enforceable programs for PM by one 
year from the dates contained in the proposed rulemaking to provide 
additional time to complete the development of these units. Second, we 
have committed to an internal EPA development program to resolve the 
remaining technical challenges with measuring PM emission onboard the 
vehicle. Third, we have entered into a comprehensive research, 
development, and demonstration program with CARB and the engine 
manufacturers to fully verify their usability, accuracy, and precision 
of portable PM measurement systems. Fourth, we have added a provision 
to the regulations that would suspend the in-use test program as it 
applies to PM measurement if we determine that fundamental technical 
problems with portable in-use PM measurement systems are not resolvable 
in a reasonable time. In summary, we believe there is an adequate basis 
to require PM measurement as part of the in-use testing program.
    Regarding the comment that it is uncertain whether any portable 
measurement system can actually measure the same physical quantities as 
the filter-based method that is used in the laboratory, as noted above, 
quartz crystal microbalance measures PM by electrostatically depositing 
mass on the QCM, and as PM deposits on the QCM its oscillating 
frequency changes in proportion to the total mass of the deposited PM. 
Because the QCM measures total PM mass directly by inertial 
acceleration, the QCM measures the same physical property; namely total 
mass, as compared to our laboratory filter-based procedure, which 
measures mass by gravitational acceleration (via a PM microbalance).
    The final comment regards measuring altitude (elevation) during an 
in-use test. In the draft technical support document, we noted that NTE 
testing will require specific information on a number of ambient 
conditions to determine if the engine is operating within the defined 
boundaries of the NTE or to calculate actual test results. We proposed 
to allow the direct measurement of these values with a specific 
technology or if the engine manufacturer determines that an engine's 
electronic control module (ECM) accurately quantifies these parameters, 
the manufacturer may rely on ECM values for those parameters. For 
altitude, we identified the use a global positioning system (GPS) as a 
suitable technology.
    Detroit Diesel Corporation recommended that EPA also accept the 
sensing of barometric pressure as an adequate surrogate for altitude 
determination. They noted that detecting barometric pressure and 
determining the corresponding altitude using standard nominal 
barometric pressure versus altitude relationship has been practiced by 
the company and found to be reliable.
    We believe that the guidance given in the draft technical support 
document remains appropriate. Direct measurement of the test altitude 
through GPS will be preferred as opposed to using a surrogate, e.g., 
sensing barometric pressure) for determining altitude. Our preference 
is based on the understanding that there will likely be errors 
associated with relying on surrogates such as barometric pressure, 
since there would be other factors, i.e., ambient conditions, 
inappropriately excluded from the altitude calculations. Nevertheless, 
as the final technical support document continues to state, we will 
allow the engine manufacturers to use the engine's ECM to determine 
altitude, but only if it can be demonstrated that it can be done 
accurately. This would be evaluated on a case-by-case basis.
    A more detailed discussion of our response to engine manufacturers 
comments regarding the status of portable particulate measurement 
technology is contained in the summary and analysis of comments 
document that accompanies today's final rule.
3. Measurement Accuracy Margin Development Program
    Manufacturer comments on the NPRM raised objections to EPA's 
proposed in-use accuracy margin value of five percent applicable to all 
pollutants covered by the program. As EPA sought clarification on these 
comments from the manufacturers and input from CARB, it became evident 
that there were legitimate concerns regarding whether or not the 
proposed accuracy margins had been sufficiently proven. In an effort to 
provide further data to develop final accuracy margins, EPA, CARB, and 
the engine manufacturers (through the Engine Manufacturers Association 
(EMA)) have entered into a Memorandum of Agreement (MOA) that details a 
project for developing data-driven accuracy margins for the gaseous 
emissions and PM fully enforceable programs. (See section II.F.3.i. of 
this preamble for more on the pilot program accuracy margins.) The MOA 
addresses the basic scope and objectives of the research, development 
and demonstration (RDD) program, program milestones and schedules, 
implementation issues, and intended implications for the regulations.
    This RDD program is expected to be completed in two main phases. 
The first phase addresses gaseous emission accuracy margins, the second 
phase addresses PM accuracy margins. A full test plan has been prepared 
for the gaseous emissions RDD program; the test plan for the PM program 
is addressed in the MOA, and is to be completed well prior to 
initiation of the RDD testing effort. Each of the two programs is 
expected to be completed in time to have data driven accuracy margins 
for the respective fully enforceable programs, 2007 model year for 
gaseous emissions and 2008 for PM emissions. EPA intends to promulgate 
these accuracy margins and any related provisions through rulemaking.
    The gaseous emissions RDD program contains four basic components. 
First, it will assess emissions, exhaust flow, and torque measurement 
variability of PEMS units incremental to the laboratory measurement. 
Second, the effect of environmental parameters and of on-vehicle time 
on measurement accuracy.

[[Page 34614]]

Third, on vehicle/trailer emission measurements versus PEMS emission 
measurements of the same operation. And fourth, it will consider 
manufacturer voluntary submissions of data that could be used to 
develop a margin component that accounts for the variability in key 
engine parameters used in the NTE brake-specific emission calculations. 
All of this information will be used to develop and validate a computer 
model which will produce a data driven accuracy margin for each of the 
gaseous emissions to be proposed as discussed above.
    The PM emissions RDD program, scheduled to begin in 2006, will 
assess the same basic questions as laid out above. Its schedule is 
offset by approximately one year to allow for full development of the 
PM RDD test program plan and continued development of PM PEMS 
capability. The PM accuracy margins and any related provisions are 
expected to be promulgated through rulemaking, with the intention that 
they apply to the 2008 model year fully enforceable program for PM 
emissions.
    The efforts under this MOA will be managed by EPA in close 
coordination with CARB and the involved engine manufacturers. Progress 
reports will be made publicly available. Interested readers are invited 
to review the full text of the MOA which is available in the public 
docket and at the EPA/OTAQ website for this rule.

M. Pilot Program

    To ensure a successful launch of the fully enforceable program for 
gaseous emissions testing in calendar year 2007, there will be a more 
limited mandatory pilot program in calendar years 2005 and 2006 for 
gaseous pollutants (i.e., nonmethane hydrocarbons (NMHC), carbon 
monoxide (CO), and oxides of nitrogen (NOX)). Similarly, the 
fully enforceable program for PM will be preceded by a pilot program 
for that pollutant in calendar years 2006 and 2007. Additionally, one 
or both of the pilot programs could be extended, and the fully 
enforceable program delayed, in the unlikely event that the process of 
identifying the final accuracy margins, discussed above, is 
significantly delayed beyond the originally scheduled completion dates.
    We will designate engine families for testing under the pilot 
program as described in section II. B. of this preamble. In all 
likelihood, we will select 2002 through 2006 model year engines for 
testing under the gaseous pilot program, and 2002 through 2007 model 
year engines under the PM pilot program. As discussed above, we will 
only designate families that have been designed to comply with the NTE. 
After receiving our selections, manufacturers will then conduct in-use 
testing based on the Phase 1 testing criteria according to the scheme 
set forth in section II. C. of this preamble. Under those requirements, 
engine manufacturers must test up to 10 vehicles per designated engine 
family. However, Phase 1 testing will be limited to a total of five 
vehicles for engine manufacturers participating in the program to 
develop the final measurement accuracy margins for portable emission 
measurement systems as described in section II. L. 3. of this preamble. 
During the two-year pilot programs for gaseous and PM emissions, both 
EPA and the heavy-duty diesel engine manufacturers will gain valuable 
experience with the in-use testing protocols, and the generation, 
interpretation, and reporting of in-use NTE emissions data.
    The evaluation of these data for compliance purposes is limited to 
screening for exceedences of the FTP certification standards as well as 
the potential use of defeat devices as outlined in prior Agency 
guidance. The pilot program data could also be used to screen consent 
decree engines certified to pull ahead NTE requirements for compliance 
with the applicable NTE limits. If the test results for manufacturers 
subject to the full pilot program clearly show that the designated 
heavy-duty diesel engine family passes the Phase 1 testing criteria 
(i.e., 5 out of 5, 5 out of 6, or 8 out of 10 vehicles pass), no 
further testing will be required of that engine family in that year. If 
the designated engine family does not clearly pass the test criteria 
(i.e., 7 or fewer out of 10 vehicles pass) we will not pursue any form 
of remedial action based solely on that data. For manufacturers 
participating in the program to develop the final accuracy measurement 
margins that must test five vehicles per designated engine family, we 
will likewise not pursue any form of remedial action based solely on 
that data. However, we may utilize these latter test results in 
conjunction with our own test data and other information to assess or 
pursue any appropriate enforcement or regulatory action.
    We proposed that the certificate of conformity for an engine family 
may be voided if the engine manufacturer did not meet its obligations 
under the in-use testing rules. International Truck and Engine Company 
commented that during the settlement negotiations, all parties 
recognized that the 2005 and 2006 pilot programs must remain flexible 
in order for it to work. Therefore, the potential consequences of 
voiding a certificate of conformity for failing to strictly adhere to 
the 2005 and 2006 pilot programs directly contradicts the cooperative 
nature of the in-use testing program.
    We agree with the commenter that the pilot program needs to remain 
flexible and cooperative in nature. However, we are retaining the 
provision for the pilot program as a way to assure that all engine 
manufacturers participate in that part of the mandatory in-use testing 
pilot program. We do not anticipate a reason to revoke a certificate of 
conformity if the manufacturer shows a good faith effort in conducting 
the pilot program.

N. Public Availability of In-Use Testing Data

    We noted in the proposal that in-use test data reported under the 
program would be available to the general public for review and 
analysis. The engine manufacturers objected to providing public access 
to all test data and underlying information. They specifically stated 
that information pertaining to how a manufacturer ``controls'' an 
engine when achieving in-use emissions compliance is confidential 
business information and must be treated as such. Manufacturers stated 
that public information should be limited to emission results and 
vehicle pass ratios.
    Our goal is to ensure the confidentiality a manufacturer's 
confidential business information (CBI) while making the in-use test 
program as transparent and useful to others as possible. After 
carefully considering how to balance these competing interests, we will 
make the following information publically available: Engine family, 
model, and rating identification; description of test route and test 
conditions; engine speed and torque, mass emissions, and work performed 
each at a 1 Hz interval; emissions results (for each valid NTE event); 
vehicle pass ratio; and any other information needed to calculate the 
summary emissions results and the NTE zone for that engine. We will 
also make available a generic indication as to whether a deficiency or 
carve-out has been encountered for each second of the test. Information 
that a manufacturer may designate as CBI will be safeguarded and 
withheld from public release by the Agency subject to EPA's CBI 
regulations.\11\ Except as listed above as

[[Page 34615]]

publically available, such information will include, but is not limited 
to, engine operating and control parameters designated CBI during the 
certification process (including those associated with auxiliary 
emissions control devices) and the information necessary to identify 
specific and complete regions of the NTE control zone where: (1) A 
manufacturer has been granted an allowance by EPA to temporarily exceed 
the NTE standards under certain limited circumstances (i.e., 
deficiencies), or (2) the emissions contribution from a portion of the 
NTE zone has been limited in determining compliance with the NTE 
standards (i.e., carve-outs).
---------------------------------------------------------------------------

    \11\ If EPA receives a request under the Freedom of Information 
Act for records relating to manufacturers' required in-use testing, 
it is EPA's standard operating procedure to initially deny the 
requestor any responsive records containing information submitted 
under CBI claims by the manufacturers. The manufacturers who 
submitted the information under CBI claims will be required to 
substantiate their claims, and the EPA Office of General Counsel 
will make a final determination of confidentiality for the 
information. See 40 CFR 2.204 and 205.
---------------------------------------------------------------------------

O. Implications for Other EPA Programs

1. EPA Testing and Supplemental Information
    EPA reserves its preexisting authority to conduct repeat testing or 
initiate our own in-use testing of a manufacturer's heavy-duty diesel 
engine family. The purpose of this testing would be primarily to verify 
and supplement, not duplicate, the testing program to be conducted by 
manufacturers. Therefore, we do not intend to conduct routine in-use 
NTE testing of engines or engine families that satisfy the Phase 1 
testing criteria, unless new information indicates that a potential 
nonconformity exists. We will also inform and invite the affected 
manufacturer to observe any in-use testing that we may conduct which is 
related to this program.
2. Selective Enforcement Audit (SEA) Testing
    We will limit the existing SEA program after full implementation of 
the manufacturer-run, in-use program solely to instances where credible 
evidence indicates the existence of a nonconformity. Such evidence may 
include: Past noncompliance occurring in new engines or very early in 
the life of in-use engines, a manufacturer's quality assurance/quality 
control (QA/QC) reporting that identifies or otherwise indicates a 
problem, a significant number of consumer complaints or defect reports, 
or test data of any type.
    In general, we anticipate that a robust, mature manufacturer-run 
in-use program would significantly reduce the role SEA plays in EPA's 
compliance program. Assembly line emissions audits ensure that the 
prototype emission control designs approved during the certification 
process successfully transfer into mass produced engines. More 
specifically, SEAs evaluate whether manufacturers' design enough 
compliance margin into the certified emissions levels to account for 
the emissions variability inherent to the design and manufacture of a 
particular engine and emissions control system.
    It is expected that the in-use program will require manufacturers 
to target emissions performance with enough compliance margin below the 
standards to account for expected in-use deterioration, and that this 
margin will exceed normal emissions variability experienced in new 
engines. The use of aftertreatment as the primary means for emissions 
control is expected further to reduce EPA's reliance on SEAs as a 
compliance tool. These systems typically function at high efficiency 
levels and without catastrophic failure on newer engines. If problems 
were to occur, it is often only apparent after the aftertreatment-
equipped engine has been in service for some period of time. During SEA 
testing, the aftertreatment system will have experienced little mileage 
accumulation and, therefore, is expected to perform at essentially 
undeteriorated levels. For these reasons, EPA believes SEA testing will 
be less critical for a vigorous enforcement program.
    As mentioned previously, there are circumstances where SEAs would 
still be warranted. Those situations typically involve known or 
expected problems which occur relatively early in the engine's useful 
life, but have not been remedied by the manufacturer. In those cases, 
it is less expensive and more effective to remedy the problem well in 
advance of in-use testing. EPA is also interested in occasionally 
conducting SEAs for small engine families that may not be the focus of 
testing under the manufacturer-run, in-use testing program.
3. Deterioration Factor Testing
    Under our current emissions certification program requirements, 
manufacturers of heavy-duty diesel engines are allowed considerable 
flexibility in generating deterioration factors (DFs). The regulations 
only generally specify how to stabilize the engine system prior to 
conducting the durability testing. All other aspects of generating DFs, 
such as the durability test cycle and the duration of the testing, are 
left to the good engineering judgement of the engine manufacturer. 
Given this latitude, manufacturers have settled on a fairly standard 
set of methodologies for generating DFs.
    Deterioration factors are generated in the laboratory using an 
engine dynamometer. After the engine is stabilized, it is exercised 
over a durability driving cycle for a period of time or mileage 
established by the engine manufacturer as mentioned previously. 
Emissions are measured over this cycle at intervals specified by the 
engine manufacturer. The measured emissions are plotted as a function 
of time or mileage and a statistical curve fitting method is used to 
calculate emissions deterioration over time. Since the emission tests 
are not typically performed to the end of engine's useful life, the 
curve-fit is extrapolated to estimate useful life emissions. Either the 
measured initial, early-life emissions are subtracted from the 
extrapolated useful life emissions (additive DF), or the useful life 
emissions are divided by the early-life emissions (multiplicative DF), 
depending on the emissions control technology, to calculate the DF and 
arrive at the official deteriorated certification test results.
    The 2004 and 2007 low emission standards required for heavy-duty 
diesel engines has placed the efficacy of how these traditional DF 
methodologies are developed and applied under increased scrutiny by 
both EPA and the engine manufacturers. The reasons are twofold. First, 
aftertreatment and add-on emissions control technologies such as 
cooled-EGR are more prone to deterioration compared to past engine 
designs. Second, compliance with the emissions standards becomes more 
sensitive to the uncertainty in the emissions trends resulting from 
these common DFs methods as the stringency of the standards increases. 
In the past, manufacturers could target emissions far enough below the 
relatively relaxed emissions standards in order to account for the 
inherent DF variability. The increased stringency of the 2004 and 2007 
standards have reduced those traditional compliance margins, leaving 
less headroom to account for DF uncertainty. Exacerbating the issue is 
the traditional use of multiplicative DFs which mathematically result 
in a larger deteriorated emissions value compared to an additive 
approach.
    The most likely solution for addressing the loss in confidence with 
current DF methods in the near term is for EPA and the engine 
manufacturers to work cooperatively to establish more robust 
accelerated DF methodologies in the laboratory. This would provide more 
certain deteriorated certification emission results. Discussions on 
such a solution have already started on an

[[Page 34616]]

informal basis with individual manufacturers and will become more 
structured with industry in the near future.
    As a longer term approach, it may be possible to reduce or 
eliminate the current laboratory-based DF methods by using the test 
results generated as part of the proposed manufacturer-run in-use 
testing program or test data from other in-use testing that utilizes 
portable emission measurement systems to more accurately predict in-use 
deterioration. For example, a manufacturer may be able to demonstrate 
that DFs generated from the in-use data are superior predictors of 
useful life deterioration, or at least correlate well with the more 
traditional laboratory approach to developing these factors. To this 
end, we intend to assess the generation and submission of DFs based on 
the proposed 2005 and 2006 pilot program. We will examine potential 
ways to diminish or eliminate burdens on manufacturers of generating 
and submitted DFs, while still generating DFs that accurately predict 
in-use deterioration. Any appropriate revisions for generating DFs 
would be promulgated in a subsequent rulemaking action, particularly in 
the rulemaking reexamining the accuracy margin discussed in II. F. 
above.

P. Limitations of Warranty Claims

    An exceedence of the NTE found through the in-use testing program 
is not by itself sufficient to show a breach of the warranty under 
section 207(a)(1)(A) or (B). A breach of this warranty would also 
require either: (1) That, at the time of sale, the engine or vehicle 
was designed, built and equipped in a manner that does not conform in 
all material respects reasonably related to emission controls to the 
engine as described in the application for certification and covered by 
the certificate, or (2) a defect in materials and workmanship of a 
component or part that causes the vehicle or engine to fail to conform 
to the applicable regulations for its useful life. To the extent that 
in-use NTE testing does not reveal such a material deficiency at the 
time of sale in the design or manufacture of an engine compared to the 
certified engine, or a defect in the materials and workmanship of a 
component or part, test results showing an exceedence of the NTE by 
itself would not show a breach of the warranty under section 207(a)(1).

III. Economic Impacts

    The costs associated with the rule to implement a manufacturer-run, 
in-use NTE testing program for heavy-duty diesel engines depends 
primarily on how many vehicles are eventually tested under the Phase 1 
and 2 testing schemes. This is difficult to estimate because the actual 
number for each designated engine family depends on how may vehicles 
pass, or fail, the vehicle pass criteria at various points in the 
tiered testing design. It is also highly dependent on how manufacturers 
chose to conduct the test program and the availability of test 
vehicles. However, based on our experience with in-use emissions 
testing, including the development and use of portable measurement 
systems for compliance testing, and comments from an engine 
manufacturer, we identified a reasonable testing scenario that allows 
us to estimate the potential costs associated with the program. This 
analysis is based on 13 manufacturers who certified 71 engine families 
in 2005. Costs are in 2004 dollars.
    Our analysis shows a total cost of approximately $1.6 million per 
year for the case where no manufacturer must test more than the minimum 
number of vehicles under Phase 1 (i.e., 5 vehicles per engine family). 
If all manufacturers were to test the maximum number of vehicles 
required under Phase 1 (i.e., 10 vehicles per engine family), the total 
cost would be about $1.7 million per year. In the most unlikely worst 
case scenario where all manufacturers must test the maximum vehicles in 
Phase 1 and 2 (i.e., 20 vehicles per engine family), the total cost 
would be about $2.1 million per year. Our best estimate of the overall 
cost of the proposed program is $1.7 million per year for the entire 
industry. The Technical Support Document for this rule contains a 
detailed description of our economic analysis.
    Overall, while not insignificant, these costs are quite low 
compared to other in-use compliance programs. Moreover, they are 
especially attractive in comparison to a more traditional in-use 
testing program where the engine must be extracted from the vehicle and 
tested on an engine dynamometer in the laboratory. In that situation, 
each engine test could cost $25,000 if the vehicle could be procured 
from an in-use fleet.

IV. Public Participation

    In the proposed rule, we invited public participation in a public 
hearing and a comment period for written comments. We held the public 
hearing on July 15, 2004 to receive comments on the rule. Only the on-
highway, heavy-duty diesel engine manufacturers that are affected by 
the rule presented testimony. We also received written comments from 
about 10 organizations, ranging from State offices of environmental 
protection to the engine manufacturers. The previous sections of this 
preamble describe the significant comments and our responses. The Final 
Technical Support Document addresses the full range of comments.

V. Statutory and Executive Order Reviews

A. Executive Order 12866: Regulatory Planning and Review

    Under Executive Order 12866 the Agency must determine whether the 
regulatory action is ``significant'' and therefore subject to review by 
the Office of Management and Budget (OMB) and the requirements of this 
Executive Order. The Executive Order defines a ``significant regulatory 
action'' as any regulatory action that is likely to result in a rule 
that may:
     Have an annual effect on the economy of $100 million or 
more or adversely affect in a material way the economy, a sector of the 
economy, productivity, competition, jobs, the environment, public 
health or safety, or State, local, or tribal governments or 
communities;
     Create a serious inconsistency or otherwise interfere with 
an action taken or planned by another agency;
     Materially alter the budgetary impact of entitlements, 
grants, user fees, or loan programs, or the rights and obligations of 
recipients thereof; or
     Raise novel legal or policy issues arising out of legal 
mandates, the President's priorities, or the principles set forth in 
the Executive Order.
    The Office of Management and Budget reviewed this rule under the 
provisions of Executive Order 12866. Any new costs associated with this 
rule will be small. See the Technical Support Document for more 
information.

B. Paperwork Reduction Act

    The Office of Management and Budget (OMB) has approved the 
information collection requirements contained in this rule under the 
provisions of the Paperwork Reduction Act, 44 U.S.C. 3501 et seq. and 
has assigned OMB control number 2060-0287 (EPA ICR 1684.08). 
The Agency will collect information to ensure compliance with the 
provisions in this rule. Section 208(a) of the Clean Air Act requires 
that engine manufacturers provide information the Administrator may 
reasonably require to determine compliance with the regulations; 
submission of the information is therefore mandatory. We will consider 
confidential all information meeting the

[[Page 34617]]

requirements of Section 208(c) of the Clean Air Act.
    As shown in Table V-1, the total annual burden associated with this 
proposal is about 3,614 hours and $1,669,000 based on a projection of 
13 respondents. The estimated burden for on-highway, heavy-duty diesel 
engine manufacturers is a total estimate for both new and existing 
reporting requirements. 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; and transmit or otherwise disclose the 
information.

                    Table V-1.--Estimated Burden for Reporting and Recordkeeping Requirements
----------------------------------------------------------------------------------------------------------------
                                                                  Number of      Annual burden
                       Industry sector                           respondents         hours         Annual costs
----------------------------------------------------------------------------------------------------------------
Engines......................................................              13            3,614       $1,669,000
----------------------------------------------------------------------------------------------------------------

    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 are listed in 40 CFR part 9 and 48 CFR chapter 15.

C. Regulatory Flexibility Act

    EPA has determined that it is not necessary to prepare a regulatory 
flexibility analysis in connection with this 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 as defined 
by the Small Business Administration (SBA)'s regulations 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. 
This final rule will not impose any requirements on small entities. The 
test procedures that are established by this rule pertain to heavy-duty 
diesel engine manufacturers. EPA has previously analyzed this category 
for impact on small entities when emission standards were finalized for 
this category of engines in October of 2000 (65 FR 59895, October 6, 
2000). At that time, EPA noted that two small entities were known to be 
affected. Those entities were small businesses that certify alternative 
fuel engines or vehicles, either newly manufactured or modified from 
previously certified gasoline engines. The test procedures adopted by 
this action do not pertain to the engines manufactured by these small 
businesses and recent analysis supports that there are no additional 
small businesses that would be impacted by this action.

D. Unfunded Mandates Reform Act

    Title II of the Unfunded Mandates Reform Act of 1995 (UMRA), Pub. 
L. 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 that 
alternative was not 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 significantly or uniquely affects small 
governments. We have 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. 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'' is 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 proposed regulation. EPA also may not issue a

[[Page 34618]]

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 proposed 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.

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

    Executive Order 13175, entitled ``Consultation and Coordination 
with Indian Tribal Governments'' (65 FR 67249, 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.''
    This rule does not have tribal implications as specified in 
Executive Order 13175. This rule will be implemented at the Federal 
level and impose compliance costs only on heavy-duty diesel, on-highway 
engine manufacturers. Tribal governments will be affected only to the 
extent they purchase and use equipment with regulated engines. 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 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 does not 
involve decisions on environmental health or safety risks that may 
disproportionately affect children.

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 effect 
on the supply, distribution, or use of energy.

I. National Technology Transfer Advancement Act

    Section 12(d) of the National Technology Transfer and Advancement 
Act of 1995 (``NTTAA''), Pub. L. 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 (e.g., 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. There 
are no voluntary consensus standards for the testing required under 
this final rule.

J. Congressional Review Act

    The Congressional Review Act, 5 U.S.C. 801 et seq., as added 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 each House of the Congress and to the Comptroller General of the 
United States. EPA 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 prior 
to publication of the rule in the Federal Register. This rule is not a 
``major rule'' as defined by 5 U.S.C. 804(2). The Office of Management 
and Budget reviewed this rule under the provisions of Executive Order 
12866. Any new costs associated with this final rule will be minimal.

VI. Statutory Provisions and Legal Authority

    Statutory authority for the engine controls adopted in this rule is 
in 42 U.S.C. 7401-7671q.

List of Subjects

40 CFR Part 9

    Reporting and recordkeeping requirements.

40 CFR Part 86

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

    Dated: June 3, 2005.
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 set forth below.

PART 9--OMB APPROVALS UNDER THE PAPERWORK REDUCTION ACT

0
1. The authority citation for part 9 continues to read as follows:

    Authority: 7 U.S.C. 135 et seq., 136-136y; 15 U.S.C. 2001, 2003, 
2005, 2006, 2601-2671; 21 U.S.C. 331j, 346a, 348; 31 U.S.C. 9701; 33 
U.S.C. 1251 et seq., 1311, 1313d, 1314, 1318 1321, 1326, 1330, 1342 
1344, 1345 (d) and (e), 1361; E.O. 11735, 38 FR 21243, 3 CFR, 1971-
1975 Comp. p. 973; 42 U.S.C. 241, 242b, 243, 246, 300f, 300g, 300g-
1, 300g-2, 300g-3, 300g-4, 300g-5, 300g-6, 300j-1, 300j-2, 300j-3, 
300j-4, 300j-9, 1857 et seq., 6901-6992k, 7401-7671q, 7542, 9601-
9657, 11023, 11048.


0
2. Section 9.1 is amended in the table by removing the heading 
``Control of Air Pollution From New and In-Use Motor Vehicles and New 
and In-Use Motor Vehicle Engines: Certification and Test Procedures'' 
and adding the following new heading in its place ``Control of 
Emissions From New and In-Use Highway Vehicles and Engines'' and a new 
entry under the heading in numerical order to read as follows:

[[Page 34619]]

Sec.  9.1  OMB approvals under the Paperwork Reduction Act.

* * * * *

------------------------------------------------------------------------
                                                             OMB control
                      40 CFR citation                            No.
------------------------------------------------------------------------
 
                                * * * * *
------------------------------------------------------------
  Control of Emissions From New and In-Use Highway Vehicles and Engines
------------------------------------------------------------------------
 
                                * * * * *
86.1920--86.1925...........................................    2060-0287
 
                                * * * * *
------------------------------------------------------------------------

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

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

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


0
4. Section 86.1 is amended by adding an entry at the end of the table 
in paragraph (b)(1) and adding paragraph (b)(6) to read as follows:


Sec.  86.1  Reference materials.

* * * * *
    (b) * * *
    (1) * * *

------------------------------------------------------------------------
                                                                 40 CFR
                    Document No. and name                       part 86
                                                               reference
------------------------------------------------------------------------
 
                                * * * * *
ASTM D 975-04c Standard Specification for Diesel Fuel Oils...    86.1910
------------------------------------------------------------------------

* * * * *
    (6) NIST material. The following table lists material from the 
National Institute of Standards and Technology that we have 
incorporated by reference. The first column lists the number and name 
of the material. The second column lists the sections of this part 
where we reference it. Anyone may purchase copies of these materials 
from the Government Printing Office, Washington, DC 20402 or download 
them from the Internet at http://www.nist.gov/.

------------------------------------------------------------------------
                                                                Part 86
                    Document No. and name                      reference
------------------------------------------------------------------------
NIST Special Publication 811, Guide for the Use of the           86.1901
 International System of Units (SI), 1995 Edition............
------------------------------------------------------------------------


0
5. Section 86.007-11 is amended by adding paragraph (a)(4)(vi) to read 
as follows:


Sec.  86.007-11  Emission standards and supplemental requirements for 
2007 and later model year diesel heavy-duty engines and vehicles.

* * * * *
    (a) * * *
    (4) * * *
    (vi) Manufacturers are not required to provide engine information 
exclusively related to in-use testing as part of initial certification. 
However, upon request from EPA the manufacturers must provide the 
information which clearly identifies parameters defining all NTE 
deficiencies described under paragraph (a)(4)(iv) of this section and 
parameters defining all NTE limited testing regions described under 
Sec.  86.1370-2007(b)(6) and (7) that are requested. When requested, 
deficiencies and limited testing regions must be reported for all 
engine families and power ratings in English with sufficient detail for 
us to determine if a particular deficiency or limited testing region 
will be encountered in the emission test data from the portable 
emission-sampling equipment and field-testing procedures referenced in 
Sec.  86.1375. Such information is to be provided within 60 days of the 
request from EPA.
* * * * *

0
6. A new Sec.  86.1375-2007 is added to read as follows:


Sec.  86.1375-2007  Equipment specifications for field testing.

    For testing conducted with engines installed in vehicles, including 
field testing conducted to measure emissions under Not-To-Exceed test 
procedures, use the test procedures and equipment specified in 40 CFR 
part 1065, subpart J.

0
7. A new subpart T is added to read as follows:

Subpart T--Manufacturer-Run In-Use Testing Program for Heavy-Duty 
Diesel Engines

Sec.
86.1901 What testing requirements apply to my engines that have gone 
into service?
86.1905 How does this program work?
86.1908 How must I select and screen my in-use engines?
86.1910 How must I prepare and test my in-use engines?
86.1912 How do I determine whether an engine meets the vehicle-pass 
criteria?
86.1915 What are the requirements for Phase 1 and Phase 2 testing?
86.1917 How does in-use testing under this subpart relate to the 
emission-related warranty in Section 207(a)(1) of the Clean Air Act?
86.1920 What in-use testing information must I report to EPA?
86.1925 What records must I keep?
86.1930 What special provisions apply from 2005 through 2007?
86.1935 What special provisions may apply as a consequence of a 
delay in the accuracy margin report for portable emission 
measurement systems?

Appendix I to Subpart T--Sample Graphical Summary of NTE Emission 
Results


Sec.  86.1901  What testing requirements apply to my engines that have 
gone into service?

    (a) If you manufacture diesel heavy-duty engines above 8500 lbs. 
GVWR that are subject to engine-based exhaust emission standards under 
this part, you must test them as described in this subpart. You must 
measure all emissions listed in Sec.  86.1910(d) other than PM 
beginning in calendar year 2005 and you must measure PM emissions 
beginning in calendar year 2006. See Sec. Sec.  86.1930 and 86.1935 for 
special provisions that may apply to manufacturers in the early years 
of this program.
    (b) We may void your certificate of conformity for an engine family 
if you do not meet your obligations under this subpart. We may also 
void individual tests and require you to retest those vehicles or take 
other appropriate measures in instances where you have not performed 
the testing in accordance with the requirements described in this 
subpart.
    (c) In this subpart, the term ``you'' refers to the certificate-
holder for any engines subject to the requirements of this subpart.
    (d) In this subpart, round means to round numbers according to NIST 
Special Publication 811(incorporated by reference in Sec.  86.1).


Sec.  86.1905  How does this program work?

    (a) You must test in-use engines from the families we select. We 
may select the following number of engine families for testing, except 
as specified in paragraph (b) of this section:
    (1) We may select up to 25 percent of your engine families in any 
calendar year, calculated by dividing the number of engine families you 
certified in the model year corresponding to the calendar year by four 
and rounding to the nearest whole number. We will consider only engine 
families with annual U.S.-directed production volumes above 1,500 units 
in calculating the number of engine families subject to testing each 
calendar year under the annual 25 percent engine family limit. In 
addition, for model year 2007 through 2009, identical engine families 
that are split into two subfamilies under Sec.  86.007-15(m)(9) will 
count as only one engine family. If you have only three or fewer 
families that each exceed an annual U.S.-directed production volume of 
1,500 units, or if you have no engine families

[[Page 34620]]

above this limit, we may select one engine family per calendar year for 
testing.
    (2) Over any four-year period, we will not select more than the 
average number of engine families that you have certified over that 
four-year period (the model year when the selection is made and the 
preceding three model years), based on rounding the average value to 
the nearest whole number.
    (b) If there is clear evidence of a nonconformity with regard to an 
engine family, we may select that engine family without counting it as 
a selected engine family under paragraph (a) of this section. We will 
consult with you in reaching a conclusion whether clear evidence of a 
nonconformity exists for any engine family. In general, there is clear 
evidence of a nonconformity regarding an engine family under this 
subpart in any of the following cases:
    (1) The engine family was not remedied but is a carry-over from an 
engine family you tested under this subpart and was subsequently 
remedied based at least in part on the Phase 1 or Phase 2 testing 
outcomes described in Sec.  86.1915.
    (2) The engine family was not remedied but is a carry-over from an 
engine family that was remedied based on an EPA in-use testing program.
    (c) We may select any individual engine family for testing, 
regardless of its production volume, as long as we do not select more 
than the number of engine families described in paragraph (a) of this 
section. We may select an engine family from the current model year or 
any previous model year, except that we will not select any engine 
families from model years before 2007 beginning in the following 
calendar years:
    (1) 2007 for all emissions testing other than PM testing.
    (2) 2008 for PM testing.
    (d) You must complete all the required testing and reporting under 
this subpart within 18 months after we direct you to test a particular 
engine family. We will typically select engine families for testing and 
notify you in writing by June 30 of the applicable calendar year. You 
may ask for up to six months longer to complete Phase 2 testing if 
there is a reasonable basis for needing more time. In very unusual 
circumstances you may request an additional six months to complete 
Phase 2 testing.
    (e) If you make a good-faith effort to access enough test vehicles 
to complete Phase 1 or Phase 2 testing requirements under this subpart 
for an engine family, but are unable to do so, you must ask us either 
to modify the testing requirements for the selected engine family or, 
in the case of Phase 1 testing, to select a different engine family.
    (f) After you complete the in-use testing requirements for an 
engine family that we selected for testing in a given calendar year, we 
may select that same family in a later year to evaluate the engine 
family's compliance closer to the end of its useful life. This would 
count as an additional engine-family selection under paragraph (a) of 
this section, except as described in paragraph (b) of this section.
    (g) For any communication related to this subpart, contact the 
Engine Programs Group Manager (6405-J), U.S. Environmental Protection 
Agency, 1200 Pennsylvania Ave., NW., Washington, DC 20460.


Sec.  86.1908  How must I select and screen my in-use engines?

    (a) Once we direct you to do testing under this subpart, you must 
make arrangements to select test vehicles and engines that meet the 
following criteria:
    (1) The engines must be representative of the engine family.
    (2) The usage of the vehicles must be representative of typical 
usage for the vehicles' particular application.
    (3) The vehicles come from at least two independent sources.
    (4) The key vehicle/engine systems (e.g., power train, drive train, 
emission control) have been properly maintained and used.
    (5) The engines have not been tampered with, rebuilt or undergone 
major repair that could be expected to affect emissions.
    (6) The engines have not been misfueled. For example, an engine may 
be considered misfueled if operated on a biodiesel fuel blend that is 
either not listed as allowed or otherwise indicated to be an 
unacceptable fuel in the vehicle's owner or operator manual.
    (7) The engines do not have an illuminated MIL or stored OBD 
trouble code that lead you to reject the vehicle from the test program 
as described in Sec.  86.1910(b)(2).
    (8) The vehicles are likely to operate for at least three hours 
(excluding idle) over a complete shift-day, as described in Sec.  
86.1910(g).
    (9) The vehicles have not exceeded the applicable useful life, in 
miles or years (see subpart A of this part); you may otherwise not 
exclude engines from testing based on their age or mileage.
    (10) The vehicle has appropriate space for safe and proper mounting 
of the PEMS equipment.
    (b) You must keep any records of a vehicle's maintenance and use 
history you obtain from the owner or operator, as required by Sec.  
86.1925. You must report the engine's maintenance and use history and 
information related to the OBD system, as described in Sec.  86.1920.
    (c) You must notify us before rejecting a candidate vehicle for 
reasons other than failing to meet the acceptance criteria in paragraph 
(a) of this section. A candidate vehicle is any prospective vehicle you 
have identified to potentially fulfill your testing requirements under 
this subpart. Include your reasons for rejecting each vehicle. If an 
owner declines to participate in the test program, you may reject the 
vehicle without prior notification. Such a rejection must be reported 
as described in Sec.  86.1920. We may allow you to replace the rejected 
vehicle with another candidate vehicle to meet your testing 
requirements for the specific engine family.
    (d) You must report when, how, and why you reject candidate 
vehicles, as described in Sec.  86.1920.


Sec.  86.1910  How must I prepare and test my in-use engines?

    (a) You must limit maintenance to what is in the owners manual for 
engines with that amount of service and age. For anything we consider 
an adjustable parameter (see Sec.  86.094-21(b)(1)(ii) and Sec.  
86.094-22(e)), you may adjust that parameter only if it is outside of 
its adjustable range. You must then set the adjustable parameter to the 
mid-point of its adjustable range or your recommended setting, unless 
we approve your request to do otherwise. You must receive permission 
from us before adjusting anything not considered to be an adjustable 
parameter. You must keep records of all maintenance and adjustments, as 
required by Sec.  86.1925. You must send us these records, as described 
in Sec.  86.1920(b)(3)(x), unless we instruct you not to send them.
    (b) You may treat a vehicle with an illuminated MIL or stored 
trouble code as follows:
    (1) If the length of MIL illumination or trouble code storage is 
consistent with proper maintenance and use, either test the prospective 
test vehicle as received or repair the vehicle before testing. If you 
elect to repair the vehicle/engine, but ultimately determine that 
repairs cannot be completed in a timely manner, you may reject the 
vehicle from the test program and replace it with another vehicle. If 
you repair or reject the vehicle, you must describe the MIL or trouble 
code information in your report under Sec.  86.1920.
    (2) If the length of MIL illumination or trouble code storage is 
inconsistent with proper maintenance and use, either

[[Page 34621]]

test the prospective test vehicle as received, repair the vehicle 
before testing, or reject the vehicle from the test program and replace 
it with another vehicle. If you repair or reject the vehicle, you must 
describe the MIL or trouble code information in your report under Sec.  
86.1920.
    (3) If a MIL is illuminated or a trouble code is set during an in-
use test, do one of the following:
    (i) Stop the test, repair the vehicle, and restart the testing. In 
this case, only the portion of the full test results without the MIL 
illuminated or trouble code set would be used in the vehicle-pass 
determination as described in Sec.  86.1912. Describe the MIL or 
trouble code information in your report under Sec.  86.1920.
    (ii) Stop the test, repair the vehicle, and initiate a new test. In 
this case, only the post-repair test results would be used in the 
vehicle-pass determination as described in Sec.  86.1912. Describe the 
MIL or trouble code information in your report under Sec.  86.1920.
    (iii) If three hours of non-idle operation have been accumulated 
prior to the time a MIL is illuminated or trouble code set, stop the 
test and use the accumulated test results in the vehicle-pass 
determination as described in Sec.  86.1912.
    (iv) If three hours of non-idle operation have not been accumulated 
prior to the time a MIL is illuminated or trouble code is set, and you 
elect to repair the vehicle/engine, but ultimately determine that 
repairs cannot be completed in a timely manner, you may reject the 
vehicle from the test program and replace it with another vehicle. If 
you repair or reject the vehicle, you must describe the MIL or trouble 
code information in your report under Sec.  86.1920.
    (c) Use appropriate fuels for testing, as follows:
    (1) You may use any diesel fuel that meets the specifications for 
No. 2-D S500 or No. 2-D S15 in ASTM D 975 (incorporated by reference in 
Sec.  86.1), as required in the calendar year that in-use testing 
occurs.
    (2) You may use any biodiesel fuel blend that is either expressly 
allowed or not otherwise indicated as an unacceptable fuel in the 
vehicle's owner or operator manual or in the engine manufacturer's 
published fuel recommendations.
    (3) You may drain a prospective test vehicle's fuel tank(s) and 
refill the tank(s) with diesel fuel conforming to ASTM D 975 
specifications described in paragraph (c)(1) of this section.
    (4) Any fuel that is added to the fuel tank(s) of a prospective 
test vehicle, or during an in-use test, must be purchased at a local 
retail establishment near the site of vehicle procurement or screening, 
or along the test route. Alternatively, the fuel may be drawn from a 
central fueling source, provided that the fuel used is representative 
of that which is commercially available in the area where the vehicle 
is operated.
    (5) No post-refinery fuel additives are allowed, except that one or 
more specific fuel additives may be used during in-use testing if you 
can document that the owner/operator of the prospective test vehicle 
has a history of normally using the fuel treatment(s), and the fuel 
additive(s) is not prohibited in the vehicle's owner or operator manual 
or in the engine manufacturer's published fuel-additive 
recommendations.
    (6) You may take fuel samples from test vehicles to ensure that 
appropriate fuels were used during in-use testing. If a vehicle fails 
the vehicle-pass criteria and you can show that an inappropriate fuel 
was used during the failed test, that particular test may be voided. 
You may drain the vehicle's fuel tank(s) and refill the tank(s) with 
diesel fuel conforming to the ASTM D 975 specifications described in 
paragraph (c)(1) of this section. You must report any fuel tests that 
are the basis of voiding a test in your report under Sec.  86.1920.
    (d) You must test the selected engines while they remain installed 
in the vehicle. Use portable emission-sampling equipment and field-
testing procedures referenced in Sec.  86.1375. Measure emissions of 
THC, NMHC (by any method specified in 40 CFR part 1065, subpart J), CO, 
NOX, PM (as appropriate), O2, and CO2.
    (e) For Phase 1 testing, you must test the engine under conditions 
reasonably expected to be encountered during normal vehicle operation 
and use consistent with the general NTE requirements described in Sec.  
86.1370-2007(a). For the purposes of this subpart, normal operation and 
use would generally include consideration of the vehicle's normal 
routes and loads (including auxiliary loads such as air conditioning in 
the cab), normal ambient conditions, and the normal driver.
    (f) For Phase 2 testing, we may give specific directions, as 
described in Sec.  86.1915(c)(2).
    (g) Once an engine is set up for testing, test the engine for at 
least one shift-day. To complete a shift-day's worth of testing, start 
sampling at the beginning of a shift and continue sampling for the 
whole shift, subject to the calibration requirements of the portable 
emissions measurement systems. A shift-day is the period of a normal 
workday for an individual employee. If the first shift-day of testing 
does not involve at least 3 hours of accumulated non-idle operation, 
repeat the testing for a second shift-day. If the second shift-day of 
testing also does not result in at least 3 hours of accumulated non-
idle operation, you may choose whether or not to continue testing with 
that vehicle. If after two shift-days you discontinue testing before 
accumulating 3 hours of non-idle operation on either day, evaluate the 
valid NTE samples as described in Sec.  86.1912 and include the data in 
the reporting and record keeping requirements specified in Sec. Sec.  
86.1920 and 1925. Count the engine toward meeting your testing 
requirements under this subpart and use the data for deciding whether 
additional engines must be tested under the applicable Phase 1 or Phase 
2 test plan.
    (h) You have the option to test longer than the two shift-day 
period described in paragraph (g) of this section.
    (i) You may count a vehicle as meeting the vehicle-pass criteria 
described in Sec.  86.1912 if a shift day of testing or two-shift days 
of testing (with the requisite non-idle/idle operation time as in 
paragraph (g) of this section), or if the extended testing you elected 
under paragraph (h) of this section does not generate a single valid 
NTE sampling event, as described in Sec.  86.1912(b). Count the engine 
towards meeting your testing requirements under this subpart.
    (j) You may ask us to waive measurement of particular emissions if 
you can show that in-use testing for such emissions is not necessary.


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

    In general, the average emissions for each regulated pollutant must 
remain at or below the NTE threshold in paragraph (a) of this section 
for at least 90 percent of the valid NTE sampling events, as defined in 
paragraph (b) of this section. For 2007 through 2009 model year 
engines, the average emissions from every NTE sampling event must also 
remain below the NTE thresholds in paragraph (f)(2) of this section. 
Perform the following steps to determine whether an engine meets the 
vehicle-pass criteria:
    (a) Determine the NTE threshold for each pollutant subject to an 
NTE standard by adding all three of the following terms and rounding 
the result to the same number of decimal places as the applicable NTE 
standard:
    (1) The applicable NTE standard.

[[Page 34622]]

    (2) The in-use compliance testing margin specified in Sec.  86.007-
11(h), if any.
    (3) An accuracy margin for portable in-use equipment when testing 
is performed under the special provisions of Sec.  86.1930, depending 
on the pollutant, as follows:
    (i) NMHC: 0.17 grams per brake horsepower-hour.
    (ii) CO: 0.60 grams per brake horsepower-hour.
    (iii) NOX: 0.50 grams per brake horsepower-hour.
    (iv) PM: 0.10 grams per brake horsepower-hour.
    (4) Accuracy margins for portable in-use equipment for testing not 
performed under the special provisions of Sec.  86.1930, to be 
determined by rulemaking as indicated in Sec.  86.1935.
    (b) For the purposes of this subpart, a valid NTE sampling event 
consists of at least 30 seconds of continuous operation in the NTE 
control area. An NTE event begins when the engine starts to operate in 
the NTE control area and continues as long as engine operation remains 
in this area (see Sec.  86.1370). When determining a valid NTE sampling 
event, exclude all engine operation in approved NTE limited testing 
regions under Sec.  86.1370-2007(b)(6) and any approved NTE 
deficiencies under Sec.  86.007-11(a)(4)(iv). Engine operation in the 
NTE control area of less than 30 contiguous seconds does not count as a 
valid NTE sampling event; operating periods of less than 30 seconds in 
the NTE control area, but outside of any allowed deficiency area or 
limited testing region, will not be added together to make a 30 second 
or longer event. Exclude any portion of a sampling event that would 
otherwise exceed the 5.0 percent limit for the time-weighted carve-out 
defined in Sec.  86.1370-2007(b)(7). For EGR-equipped engines, exclude 
any operation that occurs during the cold-temperature operation defined 
by the equations in Sec.  86.1370-2007(f)(1).
    (c) Calculate the average emission level for each pollutant over 
each valid NTE sampling event as specified in 40 CFR part 1065, subpart 
G, using each NTE event as an individual test interval. This should 
include valid NTE events from all days of testing.
    (d) Calculate a time-weighted vehicle-pass ratio (Rpass) 
for each pollutant. To do this, first sum the time from each valid NTE 
sampling event whose average emission level is at or below the NTE 
threshold for that pollutant, then divide this value by the sum of the 
engine operating time from all valid NTE events for that pollutant. 
Round the resulting vehicle-pass ratio to two decimal places.
    (1) Calculate the time-weighted vehicle-pass ratio for each 
pollutant as follows:
[GRAPHIC] [TIFF OMITTED] TR14JN05.001

Where:
    npass = the number of valid sampling events for which 
the average emission level is at or below the NTE threshold.
    ntotal = the total number of valid NTE sampling events.

    (2) For both the numerator and the denominator of the vehicle-pass 
ratio, use the smallest of the following values for determining the 
duration, t, of any NTE sampling event:
    (i) The measured time in the NTE control area that is valid for an 
NTE sampling event.
    (ii) 600 seconds.
    (iii) 10 times the length of the shortest valid NTE sampling event 
for all testing with that engine.
    (e) The following example illustrates how to select the duration of 
NTE sampling events for calculations, as described in paragraph (d) of 
this section:

----------------------------------------------------------------------------------------------------------------
                                                                                                   Duration used
                                                 Duration of                                            in
                  NTE sample                     NTE sample         Duration Limit Applied?        calculations
                                                  (seconds)                                          (seconds)
----------------------------------------------------------------------------------------------------------------
1............................................              45  No...............................              45
2............................................             168  No...............................             168
3............................................             605  Yes. Use 10 times shortest valid              450
                                                                NTE..
4............................................             490  Yes. Use 10 times shortest valid              450
                                                                NTE..
5............................................              65  No...............................              65
----------------------------------------------------------------------------------------------------------------

    (f) Engines meet the vehicle-pass criteria under this section if 
they meet both of the following criteria:
    (1) The vehicle-pass ratio calculated according to paragraph (d) of 
this section must be at least 0.90 for each pollutant.
    (2) For model year 2007 through 2009 engines, emission levels from 
every valid NTE sampling event must be less than 2.0 times the NTE 
thresholds calculated according to paragraph (a) of this section for 
all pollutants, except that engines certified to a NOX FEL 
at or below 0.50 g/bhp-hr may meet the vehicle-pass criteria for 
NOX if measured NOX emissions from every valid 
NTE sample are less than either 2.0 times the NTE threshold for 
NOX or 2.0 g/bhp-hr, whichever is greater.


Sec.  86.1915  What are the requirements for Phase 1 and Phase 2 
testing?

    For all selected engine families, you must do the following:
    (a) To determine the number of engines you must test from each 
selected engine family under Phase 1 testing, use the following 
criteria:
    (1) Start by measuring emissions from five engines using the 
procedures described in Sec.  86.1375. If all five engines comply fully 
with the vehicle-pass criteria in Sec.  86.1912 for all pollutants, you 
may stop testing. This completes your testing requirements under this 
subpart for the applicable calendar year for that engine family.
    (2) If one of the engines tested under paragraph (a)(1) of this 
section fails to comply fully with the vehicle-pass criteria in Sec.  
86.1912 for one or more pollutants, test one more engine. If this 
additional engine complies fully with the vehicle-pass criteria in 
Sec.  86.1912 for all pollutants, you may stop testing. This completes 
your testing requirements under this subpart for the applicable 
calendar year for that engine family.
    (3) If your testing results under paragraphs (a)(1) and (2) of this 
section do not satisfy the criteria for completing your testing 
requirements under those paragraphs for all pollutants, test four 
additional engines so you have tested a total of ten engines.
    (4) An engine that fails to fully comply with the vehicle-pass 
criteria in Sec.  86.1912 for any pollutant does not comply with the 
vehicle-pass criteria in Sec.  86.1912 for the purposes of determining 
the number of engines to test from each selected engine family under 
this paragraph.

[[Page 34623]]

    (b) For situations where a total of ten engines must be tested 
under paragraph (a)(3) of this section, the results of Phase 1 testing 
lead to the following outcomes:
    (1) If at least eight of the ten engines comply fully with the 
vehicle-pass criteria in Sec.  86.1912 for all pollutants, you may stop 
testing. This completes your testing requirements under this subpart 
for the applicable calendar year for that engine family.
    (2) If six or seven vehicles from the Phase 1 sample of test 
vehicles comply fully with the vehicle-pass criteria in Sec.  86.1912 
for all pollutants, then you must engage in follow-up discussions with 
us to determine whether any further testing (including Phase 2 
testing), data submissions, or other actions may be warranted.
    (3) If fewer than six of the ten engines tested under paragraph (a) 
of this section comply fully with the vehicle-pass criteria in Sec.  
86.1912 for all pollutants, we may require you to initiate Phase 2 
testing, as described in paragraph (c) of this section.
    (4) You may under any circumstances elect to conduct Phase 2 
testing following the completion of Phase 1 testing. All the provisions 
of paragraph (c) of this section apply to this Phase 2 testing.
    (c) If you perform Phase 2 testing for any reason, test your 
engines as follows:
    (1) You must test ten additional engines using the test procedures 
described in Sec.  86.1375, unless we require you to test fewer 
vehicles.
    (2) We may give you any of the following additional directions in 
selecting and testing engines:
    (i) We may require you to select a certain subset of your engine 
family. This may include, for example, engines within a specific power 
range, engines used in particular applications, or engines installed in 
vehicles from a particular manufacturer.
    (ii) We may direct you to test engines in a way that simulates the 
type of driving and ambient conditions associated with high emissions 
experienced during Phase 1 testing.
    (iii) We may direct you to test engines in a specific state or any 
number of contiguous states.
    (iv) We may direct you to select engines from the same sources used 
for previous testing, or from different sources.
    (v) We may require that you complete your testing and reporting 
under Phase 2 within a certain period. This period may not be shorter 
than three months and must allow a reasonable amount of time to 
identify and test enough vehicles. We would generally expect this 
testing to be completed within the overall time period specified in 
Sec.  86.1905(d).


Sec.  86.1917  How does in-use testing under this subpart relate to the 
emission-related warranty in Section 207(a)(1) of the Clean Air Act?

    (a) An exceedance of the NTE found through the in-use testing 
program under this subpart is not by itself sufficient to show a breach 
of warranty under Clean Air Act section 207(a)(1) (42 U.S.C. 
7541(a)(1)). A breach of warranty would also require one of the 
following things:
    (1) That, at the time of sale, the engine or vehicle was designed, 
built, and equipped in a manner that does not conform in all material 
respects reasonably related to emission controls to the engine as 
described in the application for certification and covered by the 
certificate; or
    (2) A defect in materials or workmanship of a component causes the 
vehicle or engine to fail to conform to the applicable regulations for 
its useful life.
    (b) To the extent that in-use NTE testing does not reveal such a 
material deficiency at the time of sale in the design or manufacture of 
an engine compared with the certified engine, or a defect in the 
materials and workmanship of a component or part, test results showing 
an exceedance of the NTE by itself would not show a breach of the 
warranty under 42 U.S.C. 7541(a)(1).


Sec.  86.1920  What in-use testing information must I report to EPA?

    (a) Send us electronic reports at [email protected] using an approved 
information format. If you want to use a different format, send us a 
written request with justification.
    (b) Within 30 days after the end of each calendar quarter, send us 
reports containing the test data from each engine for which testing was 
completed during the calendar quarter. Alternatively, you may 
separately send us the test data within 30 days after you complete 
testing for an engine. Once you send us information under this section, 
you need not send that information again in later reports. Prepare your 
test reports as follows:
    (1) For each engine family, describe how you recruited vehicles. 
Describe how you used any criteria or thresholds to narrow your search 
or to screen individual vehicles.
    (2) Include a summary of the candidate vehicles you have rejected 
and the reasons you rejected them, whether you base the rejection on 
the criteria in Sec.  86.1908(a) or anything else. If you rejected a 
candidate vehicle due to misfueling, included the results of any fuel 
sample tests.
    (3) For the test vehicle, include the following background 
information:
    (i) The EPA engine-family designation, and the engine's model 
number, total displacement, and power rating.
    (ii) The applicable test phase (Phase 1 or Phase 2).
    (iii) The date EPA selected the engine family for testing.
    (iv) The vehicle's make and model and the year it was built.
    (v) The vehicle identification number and engine serial number.
    (vi) The vehicle's type or application (such as delivery, line 
haul, or dump truck). Also, identify the type of trailer, if 
applicable.
    (vii) The vehicle's maintenance and use history.
    (viii) The known status history of the vehicle's OBD system and any 
actions the owner or operator took to address OBD trouble codes or MIL 
illumination over the vehicle's lifetime.
    (ix) Any OBD codes or MIL illumination that occur after you accept 
the vehicle for in-use testing under this subpart.
    (x) Any steps you take to maintain, adjust, modify, or repair the 
vehicle or its engine to prepare for or continue testing, including 
actions to address OBD trouble codes or MIL illumination. Include any 
steps you took to drain and refill the vehicle's fuel tank(s) to 
correct misfueling, and the results of any fuel test conducted to 
identify misfueling.
    (4) For each test, include the following data and measurements:
    (i) The date and time of testing, and the test number.
    (ii) Shift-days of testing (see Sec.  86.1910 (g)), duration of 
testing, and the total hours of non-idle operation.
    (iii) Route and location of testing. You may base this description 
on the output from a global-positioning system.
    (iv) The steps you took to ensure that vehicle operation during 
testing was consistent with normal operation and use, as described in 
Sec.  86.1910(e).
    (v) Fuel test results, if fuel was tested under Sec.  86.1908 or 
86.1910.
    (vi) The vehicle's mileage at the start of the test. Include the 
engine's total lifetime hours of operation, if available.
    (vii) Ambient temperature, dewpoint, and atmospheric pressure at 
the start and finish of each valid NTE event.
    (viii) The number of valid NTE events (see Sec.  86.1912(b)).
    (ix) Average emissions for each pollutant over each valid NTE 
event. Describe the method you used to determine NMHC as specified in 
40 CFR

[[Page 34624]]

part 1065, subpart J. See Appendix I of this subpart for an example of 
graphically summarizing NTE emission results.
    (x) Exhaust-flow measurements.
    (xi) Vehicle-pass ratios (see Sec.  86.1912(d)).
    (xii) Recorded one-hertz test data, including, but not limited to, 
the following parameters:
    (A) Ambient temperature.
    (B) Ambient pressure.
    (C) Ambient humidity.
    (D) Altitude.
    (E) Emissions of THC, NMHC, CO, CO2 or O2, 
NOX, and PM (as appropriate). Report results for 
CH4 if it was measured and used to determine NMHC.
    (F) Differential back-pressure of any PEMS attachments to vehicle 
exhaust.
    (G) Exhaust flow.
    (H) Exhaust aftertreatment temperatures, if the engine meets the 
specifications of Sec.  86.1370-2007(g).
    (I) Engine speed.
    (J) Engine brake torque.
    (K) Engine coolant temperature.
    (L) Intake manifold temperature.
    (M) Intake manifold pressure.
    (N) Throttle position.
    (O) Any parameter sensed or controlled in order to modulate the 
emission-control system or fuel-injection timing.
    (5) For each engine family, identify the applicable requirements, 
as follows:
    (i) The applicable NTE thresholds.
    (ii) Vehicle and engine information needed to identify the limited 
testing regions under Sec.  86.1370-2007(b)(6) and (7).
    (iii) Vehicle and engine information needed to identify any 
approved NTE deficiencies under Sec.  86.007-11(a)(4)(iv).
    (6) Include the following summary information after you complete 
testing with the engine:
    (i) State whether the engine meets the vehicle-pass criteria in 
Sec.  86.1912(f).
    (ii) Identify how many engines you have tested from the applicable 
engine family and how many engines still need to be tested.
    (iii) Identify how many engines from an engine family have passed 
the vehicle-pass criteria and the number that have failed the vehicle-
pass criteria (see Sec.  86.1912(f)).
    (iv) If possible, state the outcome of Phase 1 testing for the 
engine family based on the criteria in Sec.  86.1915(b).
    (c) In your reports under this section, you must do all the 
following:
    (1) Include results from all emission testing required under this 
subpart.
    (2) Describe if any testing or evaluations were conducted to 
determine why a vehicle failed the vehicle-pass criteria in Sec.  
86.1912.
    (3) Describe the purpose of any diagnostic procedures you conduct.
    (4) Describe any instances in which the OBD system illuminated the 
MIL or set trouble codes. Also describe any approved actions taken to 
address the trouble codes or MIL.
    (5) Describe any instances of misfueling, the approved actions 
taken to address the problem, and the results of any associated fuel 
sample testing.
    (6) Describe any incomplete or invalid tests that were conducted 
under this subpart.
    (d) Send us an electronic notification at [email protected] describing 
any voluntary vehicle/engine emission evaluation testing you intend to 
conduct with portable in-use measurement systems on the same engine 
families that are being tested under this subpart, from the time that 
engine family was selected for in-use testing under Sec.  86.1905 until 
the final results of all testing for that engine family are reported to 
us under this section.
    (e) Send us an electronic notification at [email protected] within 15 days after your initial review of the test data 
for a selected engine family indicates that three engines in Phase 1 
testing have failed to comply with the vehicle-pass criteria. 
Similarly, send us an electronic notification at the above electronic 
address within 3 days after your initial review of the test data for a 
selected engine family indicates that any engine in Phase 2 testing 
failed to comply with the vehicle-pass criteria.
    (f) We may ask you to send us less information in your reports than 
we specify in this section.
    (g) We may require you to send us more information to evaluate 
whether your engine family meets the requirements of this part, or to 
help inform potential decisions concerning Phase 2 testing under Sec.  
86.1915.


Sec.  86.1925  What records must I keep?

    (a) Organize and maintain your records as described in this 
section. We may review your records at any time, so it is important to 
keep required information readily available.
    (b) Keep the following paper or electronic records of your in-use 
testing for five years after you complete all the testing required for 
an engine family:
    (1) Keep a copy of the reports described in Sec.  86.1920.
    (2) Keep any additional records, including forms you create, 
related to any of the following:
    (i) The procurement and vehicle-selection process described in 
Sec.  86.1908, including the vehicle owner's name, address, phone 
number, and e-mail address.
    (ii) Pre-test maintenance and adjustments to the engine performed 
under Sec.  86.1910.
    (iii) Test results for all void, incomplete, and voluntary testing 
described in Sec.  86.1920.
    (iv) Evaluations to determine why a vehicle failed the vehicle-pass 
criteria described in Sec.  86.1912.
    (3) Keep a copy of the relevant calibration results required by 40 
CFR part 1065.


Sec.  86.1930  What special provisions apply from 2005 through 2007?

    We may direct you to test engines under this subpart for emissions 
other than PM in 2005 and 2006, and for PM emissions in 2006 and 2007. 
In these interim periods, all the provisions of this subpart apply, 
with the following exceptions:
    (a) We will select engine families for testing of emissions other 
than PM only when the manufacturer's Statement of Compliance 
specifically describes the family as being designed to comply with NTE 
requirements.
    (b) If you participate in the test program described in Sec.  
86.1935(a), you may limit your testing under Phase 1 to a maximum of 
five vehicles per selected engine family.
    (c) We will not direct you to do the Phase 2 testing in Sec.  
86.1915(c), regardless of measured emission levels.
    (d) For purposes of calculating the NTE thresholds under Sec.  
86.1912(a) for any 2006 and earlier model year engine that is not 
subject to the emission standards in Sec.  86.007-11, determine the 
applicable NTE standards as follows:
    (1) If any numerical NTE requirements specified in the terms of any 
consent decree apply to the engine family, use those values as the NTE 
standards for testing under this subpart.
    (2) If a numerical NTE requirement is not specified in a consent 
decree for the engine family, the NTE standards are 1.25 times the 
applicable FELs or the applicable emission standards specified in Sec.  
86.004-11(a)(1) or Sec.  86.098-11(a)(1).
    (e) In the report required in Sec.  86.1920(b), you must submit the 
deficiencies and limited testing region reports (see Sec.  86.007-
11(a)(4)(iv) and Sec.  86.1370-2007(b)(6) and (7)) for 2006 and earlier 
model year engines tested under this section.
    (f) Testing under this section may be extended as described in 
Sec.  86.1935(d).


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

    (a) A memorandum entitled, ``Memorandum of Agreement, Program

[[Page 34625]]

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). 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 
either gaseous emissions or 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 for the respective 
pollutant type (gaseous or PM emissions):
    (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 applicable gaseous 
or PM emission testing program will go into abeyance.
    (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 either 
gaseous emissions (NOX, NMHC and CO) or PM emissions 
described in the agreement, the following provisions apply for the 
respective pollutant type (gaseous or PM emissions):
    (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 (2007 for gaseous emissions and 2008 for PM emissions), 
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) A delay for PM emissions would not be a sufficient basis for 
delaying the program for gaseous emissions. Similarly, a delay for 
gaseous emissions would not be a sufficient basis for delaying the 
program for PM emissions.
    (iii) 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.
    (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) As described in Sec.  86.1930(b), 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.

Appendix I to Subpart T--Sample Graphical Summary of NTE Emission 
Results

    The following figure shows an example of a graphical summary of 
NTE emission results:

[[Page 34626]]

[GRAPHIC] [TIFF OMITTED] TR14JN05.002

[FR Doc. 05-11470 Filed 6-13-05; 8:45 am]
BILLING CODE 6560-50-P