[Federal Register Volume 62, Number 228 (Wednesday, November 26, 1997)]
[Notices]
[Pages 63159-63161]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 97-31138]


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ENVIRONMENTAL PROTECTION AGENCY

[FRL-5927-9]


Retrofit/Rebuild Requirements for 1993 and Earlier Model Year 
Urban Buses; Approval of a Notification of Intent to Certify Equipment

AGENCY: Environmental Protection Agency.

ACTION: Notice of Agency Certification of Equipment for the Urban Bus 
Retrofit/Rebuild Program.

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SUMMARY: The Agency received a notification of intent to certify 
equipment signed March 11, 1997 from Nelson Industries, Inc., Nelson 
Division (Nelson) with principal place of business at 1801 Highway 51 
West, P.O. Box 428, Stoughton, WI, 53589 for certification of urban bus 
retrofit/rebuild equipment pursuant to 40 CFR 85.1401 through 85.1415. 
The equipment is applicable to petroleum-fueled Detroit Diesel 
Corporation (DDC) two-stroke/cycle engines originally installed in 
urban buses from model year 1979 to model year 1993, excluding the DDC 
6L71TA 1990 model year engines, all alcohol fueled engines, and models 
which were manufactured with particulate trap devices. In addition, the 
equipment is applicable to engines which have been previously rebuilt 
using the certified DDC 6V92TA MUI or DDECII upgrade kits.1 
On July 11, 1997, EPA published a notice in the Federal Register that 
the notification had been received and made the notification available 
for public review and comment for a period of 45-days (62 FR 37228). 
EPA received no comments in response to that Federal Register notice. 
Subsequently, EPA has completed its review of this notification, and 
the Director of the Engine Programs and Compliance Division has 
determined that it meets all the requirements for certification. 
Accordingly, EPA certified this equipment in a letter to Nelson 
Industries dated October 14, 1997.
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    \1\ The DDC 6V92TA MUI upgrade kit was certified by EPA on 
October 2, 1995 (60 FR 51472). The DDC 6V92TA DDECII upgrade kit was 
certified by EPA on July 19, 1996 (61 FR 37738).
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    The certified equipment provides 25 percent or greater reduction in 
exhaust emissions of particulate matter (PM) for the engines for which 
it is certified. In addition, this equipment is certified as complying 
with a life cycle cost limit of $2,000 or less (in 1992 dollars).
    The Nelson notification, as well as other materials specifically 
relevant to it, are contained in Public Docket A-93-42, category XIX, 
entitled ``Certification of Urban Bus Retrofit/Rebuild Equipment''. 
This docket is located in room M-1500, Waterside Mall (Ground Floor), 
U.S. Environmental Protection Agency, 401 M Street SW, Washington, DC 
20460.
    Docket items may be inspected from 8:00 a.m. until 5:30 p.m., 
Monday through Friday. As provided in 40 CFR Part 2, a reasonable fee 
may be charged by the Agency for copying docket materials.

DATES: The effective date of certification is October 14, 1997, 
established in a letter from EPA to Nelson Industries. This certified 
equipment may be used immediately by urban bus operators. The impact of 
this certification on transit operators is discussed in more detail in 
section IV of today's notice.

FOR FURTHER INFORMATION CONTACT: Tom Stricker, Engine Compliance 
Programs Group, Engine Program and Compliance Division (6403J), U.S. 
Environmental Protection Agency, 401 M St. SW, Washington, D.C. 20460. 
Telephone: (202) 564-9322.

SUPPLEMENTARY INFORMATION:

I. Background

    By a notification of intent to certify signed March 11, 1997, 
Nelson applied for certification of equipment applicable to petroleum-
fueled Detroit Diesel Corporation (DDC) two-cycle engines originally 
installed in an urban bus from model year 1979 to model year 1993, 
excluding the DDC 6L71TA 1990 model year engines and models which were 
manufactured with particulate trap devices or alcohol fueled. In 
addition, Nelson requested certification for engines rebuilt using the 
certified DDC 6V92TA MUI or DDECII upgrade kits when the CEM is 
installed at the same time as the DDC rebuild kit. The notification of 
intent to certify states that the equipment being certified is a 
catalytic exhaust muffler (Nelson converter), packaged as a direct 
replacement for the muffler. The application demonstrates that the 
candidate equipment provides a 25 percent or greater reduction in 
emissions of particulate matter (PM) for petroleum fueled diesel 
engines relative to an original engine configuration with no after 
treatment installed. Certification is applicable to engines that are 
rebuilt to original specifications, or in-use engines that are not 
rebuilt at the time the Nelson converter is installed provided the 
engine is calibrated to meet the original manufacturer's specifications 
and meets engine oil consumption limits specified by Nelson. According 
to Nelson, a 6-cylinder engine that uses more than one-and-a-half 
quarts of oil per 10 hours of operation, or an 8-cylinder engine that 
uses more than 2.0 quarts of oil per 10 hours of operation, must be 
rebuilt. The Nelson Converter is certified for use on engines rebuilt 
using new DDC certified rebuild kits only in those instances where the 
Nelson converter is installed at the same time the DDC rebuild kit is 
installed on the engine.
    Using engine dynamometer testing in accordance with the Federal 
Test Procedure for heavy-duty diesel engines, Nelson documented a 53% 
PM reduction for the test engine retrofit with the Nelson Converter 
compared to a standard rebuild. The test engine with the certified 
retrofit equipment installed complies with applicable Federal emission 
standards for hydrocarbon (HC), carbon monoxide (CO), oxides of 
nitrogen (NOX), and smoke emissions in addition to 
demonstrating reductions in PM exhaust emissions.
    Table A below lists the engine models covered by this 
certification, and the PM level to which each model is certified. The 
Nelson equipment is certified to reduce PM emissions by 25 percent. The 
certification level (shown as ``PM Level with Converter'' in Table A) 
represents a 25 percent reduction in PM emissions compared to the pre-
rebuild PM level shown in the table at 40 CFR Section 
85.1403(c)(1)(iii)(A).

                                         Table A.--Certification Levels                                         
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                                               PM level                                                         
        Engine models           Model year       with         Code                       Family                 
                                              converter                                                         
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6V92TA MUI \2\...............  1979-87              0.38  All           All.                                    

[[Page 63160]]

                                                                                                                
                               1988-1989            0.23  All           All.                                    
6V92TA DDEC I................  1986-89              0.23  All           All.                                    
6V92TA DDEC II \3\...........  1988-91              0.23  All           All.                                    
                                                                                                                
1992-93......................     0.19               All  All.                                                  
6V71N........................  1973-87              0.38  All           All.                                    
6V71N........................  1988-89              0.38  All           All.                                    
6V71T........................  1985-86              0.38  All           All.                                    
8V71N........................  1973-84              0.38  All           All.                                    
6L71TA.......................  1988-89              0.23  All           All.                                    
6L71TA DDEC..................  1990-91              0.23  All           All.                                    
8V92TA.......................  1979-87              0.38  All           8V92TA.                                 
                                  1988              0.29  All                                                   
8V92TA.......................                                                                                   
8V92TA-DDEC..................     1988              0.31  All           8V92TA-DDEC II.                         
8V92TA.......................     1989              0.35  9E70          KDD0736FWH9.                            
8V92TA.......................     1989              0.29  9A90          KDD0736FWH9.                            
8V92TA.......................     1989              0.26  9G85          KDD0736FWH9.                            
8V92TA DDEC..................     1989              0.31  1A            KDD0736FZH4.                            
8V92TA.......................     1990              0.35  9E70          LDD0736FAH9.                            
8V92TA DDEC..................     1990              0.37  1A            LDD0736FZH3.                            
8V92TA DDEC..................     1991              0.19  1A or 5A      MDD0736FZH2.                            
8V92TA DDEC..................  1992-93              0.16  1D            NDD0736FZH1 &                           
                                                                        PDD0736FZH X.                           
8V92TA DDEC..................  1992-93              0.22  6A            NDD0736FZH 1 &                          
                                                                        PDD0736FZH X.                           
8V92TA DDEC..................  1992-93              0.15  5A            NDD0736FZH 1 &                          
                                                                        PDD0736FZHX.                            
8V92TA DDEC..................  1992-93              0.19  1A            NDD0736FZH 1 &                          
                                                                        PDD0736FZHX.                            
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\2\ For 6V92TA MUI models that are rebuilt using a certified DDC emissions retrofit kit, Nelson is certifying   
  the PM engine emissions to a level of 0.22 g/bhp-hr for the 1979 to 1987 models and to a level of 0.17 g/bhp- 
  hr for the 1988-1989 models provided the Nelson converter is installed at the same time the rebuild with the  
  DDC upgrade takes place. The DDC 6V92TA MUI upgrade kit certification notification was published in the       
  Federal Register on October 2, 1995 (60FR51472).                                                              
\3\ For the 6V92TA DDECII models that are rebuilt using a certified DDC emissions retrofit kit, Nelson is       
  certifying the PM engine emissions to a level of 0.17 g/bhp-hr for 1988-1990 models provided the Nelson       
  converter is installed at the same time the rebuild with the DDC upgrade takes place. The DDC 6V92TA DDECII   
  upgrade kit certification notification was published in the Federal Register on July 19, 1996 (61 FR 37738).  
Note: The original PM certification levels for the 1991 6V92TA DDEC II, 6LV71TA DDEC and 8V92TA DDEC engine     
  models are based on Federal Emission Limits (FELs)under the averaging, banking and trading program. These     
  limits are higher than the 1991 PM standard of 0.25 g/bhp-hr. The PM level listed in this table for the       
  engines that are equipped with the Nelson converter provide at least a 25% reduction from the original        
  certification levels. The 1992 to 1993 6V92TA DDEC II and 8V92TA DDEC engine models were also certified using 
  FELs under the trading and banking program and likewise the PM levels for the engines equipped with the Nelson
  converter represent at least a 25% reduction from the original certification levels.                          

    In addition to reducing PM emissions by 25% or more, this equipment 
is certified to comply with a life cycle cost limit of $2,000 or less 
(in 1992 dollars). The maximum purchase price for the Nelson converter 
is $2,091 (in August 1997 dollars), and the maximum installation time 
is stated to be 5 hours, or $201 (in August 1997 dollars). Nelson 
states that no additional maintenance cost is associated with use of 
the Nelson converter, and the test data demonstrate no fuel economy 
impact. Thus, the maximum total life cycle cost for this equipment is 
$2,292 (in August 1997 dollars), or $2,000 (in 1992 dollars). Although 
this equipment meets the life cycle cost limit associated with 25% 
reduction technology, this certification does not trigger any new 
program requirements for applicable engines. The requirement to use 
equipment certified to achieve at least a 25% reduction in PM has 
previously been triggered for some of these engines and is superseded 
by the 0.10 g/bhp-hr PM standard that has been triggered for 1979-89 
DDC 6V92TA MUI engines. The impact of this certification on transit 
operators is discussed in more detail in section IV of today's notice.

II. Summary and Analysis of Comments

    EPA received no comments in response to the July 11, 1997 Federal 
Register notice. However, EPA requested clarification from Nelson 
regarding several issues discussed below.
    The Notification of Intent to Certify (NIC) describes the baseline 
rebuilt engine used in emissions testing as having 9G75 fuel injectors 
rated at 294 horsepower (HP). However, the NIC also states that the 
initial run-in power for the engine was 277 HP. Nelson was asked to 
explain this apparent discrepancy in rated HP versus observed HP. In 
response, Nelson states that the engine was rebuilt by DDC with 9G75 
fuel injectors rated at 294 HP, although the engine only produced 277 
HP upon initial run-in. Nelson states that the DDC power rating has a 
tolerance of plus/minus 5% (279 to 306 HP for a 294 HP rating). After 
additional break-in in the test cell, the engine produced 283 HP 
(within the tolerance range) as documented in the laboratory checklist 
contained in the NIC.
    Nelson requested that certification be granted for the Nelson 
converter installed on rebuilt, and non-rebuilt engines. EPA requested 
that Nelson provide a rationale to support why the claimed PM 
reductions are appropriate for engines which have not been rebuilt. In 
response, Nelson states that the installation instructions provide 
criteria

[[Page 63161]]

which must be met in order to install the Nelson converter on non-
rebuilt engines. These criteria include maintenance of the engine in 
accordance with the original engine manufacturer's specifications, 
adjustment of all adjustable parameters in accordance with 
manufacturer's specifications, and oil consumption criteria. For 6-
cylinder engines, the oil consumption may be no greater than 1.5 quarts 
per 10 hours of service. For 8-cylinder engines, the oil consumption 
may be no greater than 2.0 quarts per 10 hours of service. These 
criteria are intended to ensure that the engine is operating within the 
worse-case PM level of 0.5 g/bhp-hr. In addition, Nelson states that 
certification testing demonstrated a PM removal of 0.16 g/bhp-hr on an 
engine emitting at 0.30 g/bhp-hr. Nelson states that it is reasonable 
to assume that an even greater mass of PM would be removed from an 
engine operating at 0.50 g/bhp-hr. Even if this is not the case, 
conservatively using a 0.16 g/bhp-hr of PM removal on such an engine 
results in a 32% reduction, which is still greater than the 25% 
reduction to which the equipment is certified. EPA believes that 
Nelson's response is adequate to support certification for applicable 
non-rebuilt engines. In addition, Nelson clarified that certification 
for use on engines rebuilt with new DDC certified rebuild kits is 
limited to instances where the Nelson converter is installed on the 
engine at the same time as the DDC rebuild kit.
    As discussed in the July 11, 1997 Federal Register notice 
requesting public comment, EPA believes that the Nelson test engine 
meets the criteria for worse-case test engine, described at 
Sec. 85.1406(a), for all two-stroke cycle engines (exclusive of the 
1990 model year DDC 6L71TA), including both mechanically and 
electronically fuel injected engines. EPA reserves the right to request 
additional information showing that PM reduction does not vary 
significantly among engine families. However, because the Nelson test 
data indicate over a 50 percent PM reduction on the DDC 6V92TA MUI test 
engine, EPA believes it reasonable to expect that electronically-
controlled engines, with the Nelson catalyst installed, will be capable 
of meeting the 25 percent reduction standard for which Nelson is 
requesting certification. EPA received no comments contrary to this 
position, and thus approves certification for both mechanically and 
electronically fuel injected engines as shown in Table A.
    Finally, EPA notes that Nelson is required to provide a 100,000 
mile emission defect warranty on the Nelson converter, and a 150,000 
mile emission performance warranty per 40 CFR 85.1409. Use of the 
Nelson Converter on an engine utilizing a DDC certified upgrade kit 
does not in any way relieve Nelson of the required warranty 
responsibilities outlined above.

III. Certification

    The Agency has reviewed this notification, along with comments 
received from interested parties, and finds that the equipment 
described in this notification of intent to certify:
    (1) Reduces particulate matter exhaust emissions by at least 25 
percent, without causing the applicable engine families to exceed other 
exhaust emissions standards;
    (2) Will not cause an unreasonable risk to the public health, 
welfare, or safety;
    (3) Will not result in any additional range of parameter 
adjustability; and,
    (4) Meets other requirements necessary for certification under the 
Retrofit/Rebuild Requirements for 1993 and Earlier Model Year Urban 
Buses (40 CFR Sections 85.1401 through 85.1415). The Agency therefore 
certified this equipment in a letter to Nelson dated October 14, 1997, 
for use in the urban bus retrofit/rebuild program as discussed below in 
section IV.

IV. Transit Operator Requirements

    Based on this certification, no new requirements are placed on 
operators and no operator will be required to purchase this equipment. 
For the 1979 through 1989 6V92TA MUI engine models, EPA has previously 
certified equipment which triggered the requirement to use equipment 
certified to the 0.10 g/bhp-hr level beginning September 15, 1997. 
Therefore, under Program 1, operators who rebuild or replace 1979 
through 1989 model year DDC 6V92TA MUI engines after this date will be 
required to use equipment certified to meet the 0.10 g/bhp-hr PM level. 
For all other engine models to which this certification applies, EPA 
has previously certified equipment which triggered the requirement to 
use equipment certified as providing a minimum 25 percent reduction in 
PM beginning December 1, 1995. The Nelson converter is certified to 
reduce PM by at least 25 percent, and can be used under program 1 to 
meet this requirement for these other engine models until such time 
that equipment is certified to trigger the 0.10 g/bhp-hr emission 
standard for these engines for less than a life cycle cost of $7,940 
(in 1992 dollars).
    Operators who choose to comply with Program 2 and install the 
Nelson equipment, will use the specified PM emission levels in Table A 
in their calculation of fleet level attained.

    Dated: November 19, 1997.
Robert Brenner,
Acting Assistant Administrator for Air and Radiation.
[FR Doc. 97-31138 Filed 11-25-97; 8:45 am]
BILLING CODE 6560-50-P