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Retrofit/Rebuild Requirements for 1993 and Earlier Model Year Urban Buses; Public Review of a Notification of Intent To Certify Equipment
[Federal Register: December 13, 1995 (Volume 60, Number 239)] [Notices] [Page 64051-64056] From the Federal Register Online via GPO Access [wais.access.gpo.gov]
ENVIRONMENTAL PROTECTION AGENCY
[FRL-5344-6] Retrofit/Rebuild Requirements for 1993 and Earlier Model Year Urban Buses; Public Review of a Notification of Intent To Certify Equipment AGENCY: Environmental Protection Agency. ACTION: Notice of agency receipt of a notification of intent to certify equipment and initiation of 45-day public review and comment period.
SUMMARY: Twin Rivers Technologies' (TRT) has submitted to the Agency a notification of intent to certify urban bus retrofit/rebuild equipment pursuant to 40 CFR Part 85, Subpart O. The notification describes equipment consisting of biodiesel fuel additive in combination with a particular exhaust system catalyst. Pursuant to Sec. 85.1407(a)(7), today's Federal Register notice summarizes the notification, announces that the notification is available for public review and comment, and initiates a 45-day period during which comments can be submitted. The Agency will review this notification of intent to certify, as well any comments it receives, to determine whether the equipment described in the notification of intent to certify should be certified. If certified, the equipment can be used by urban bus operators to reduce the particulate matter of urban bus engines. The notification of intent to certify, as well as other materials specifically relevant to it, are contained in category X of Public Docket A-93-42, entitled ``Certification of Urban Bus Retrofit/Rebuild Equipment''. This docket is located at the address listed below. Today's notice initiates a 45-day period during which the Agency will accept written comments relevant to whether or not the equipment included in this notification of intent to certify should be certified. Comments should be provided in writing to Public Docket A-93-42, Category X, at the address below, and an identical copy should be submitted to William Rutledge, also at the address below.DATES: Comments must be submitted on or before January 29, 1996.
ADDRESSES: Submit identical copies of comments to each of the two following addresses: 1. U.S. Environmental Protection Agency, Public Docket A-93-42 (Category X), Room M-1500, 401 M Street S.W., Washington, DC 20460.
2. William Rutledge, Engine Compliance Group, Engine Programs and Compliance Division (6403J), 401 ``M'' Street S.W., Washington, DC 20460.
The TRT notification of intent to certify, as well as other materials specifically relevant to it, are contained in the public docket indicated above. 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.FOR FURTHER INFORMATION CONTACT: William Rutledge, Engine Programs and Compliance Division (6403J), U.S. Environmental Protection Agency, 401 M Street S.W., Washington, DC 20460. Telephone: (202) 233-9297.
SUPPLEMENTARY INFORMATION:
I. Background
On April 21, 1993, the Agency published final Retrofit/Rebuild Requirements for 1993 and Earlier Model Year Urban Buses (58 FR 21359). The retrofit/rebuild program is intended
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to reduce the ambient levels of particulate matter (PM) in urban areas and is limited to 1993 and earlier model year (MY) urban buses operating in metropolitan areas with 1980 populations of 750,000 or more, whose engines are rebuilt or replaced after January 1, 1995. Operators of the affected buses are required to choose between two compliance options: Program 1 establishes PM emissions requirements for each urban bus engine in an operator's fleet which is rebuilt or replaced. Program 2 is a fleet averaging program that establishes specific annual target levels for average PM emissions from urban buses in an operator's fleet.
A key aspect of the program is the certification of retrofit/ rebuild equipment. To meet either of the two compliance options, operators of the affected buses must use equipment which has been certified by the Agency. Emissions requirements under either of the two compliance programs depend on the availability of retrofit/rebuild equipment certified for each engine model. To be used for program 1, equipment must be certified as meeting a 0.10 g/bhp-hr PM standard or as achieving a 25 percent reduction in PM. Equipment used for Program 2 must be certified as providing some level of PM reduction that would in turn be claimed by urban bus operators when calculating their average fleet PM levels attained under the program. For program 1, information on life cycle costs must be submitted in the notification of intent to certify in order for certification of the equipment to initiate (or trigger) program requirements. To trigger program requirements, the certifier must guarantee that the equipment will be available to all affected operators for a life cycle cost of $7,940 or less at the 0.10 g/bhp-hr PM level, or for a life cycle cost of $2,000 or less for the 25 percent or greater reduction in PM. Both of these values are based on 1992 dollars.
As noted above, operators of affected buses must use equipment which has been certified by EPA. An important element of the certification process is input from the public based on review of notifications of intent to certify. It is expected that engine manufacturers, bus manufacturers, transit operators, and industry associations will be able to provide valuable information related to the installation and use of particular equipment by transit operators. Such information will be useful to the Engine Programs and Compliance Division in its role of determining whether any specific equipment can be certified.II. Notification Of Intent To Certify
By a notification of intent to certify signed August 18, 1995, and subsequently modified by letter dated October 5, 1995, Twin Rivers Technologies, Limited Partnership (TRT), with principal place of business at 780 Washington Street, Quincy, Massachusetts 02169, applied for certification of equipment applicable to certain urban bus engines manufactured by Detroit Diesel Corporation (DDC). The notification states that the candidate equipment will provide reductions in exhaust PM, as discussed below, dependent upon the configuration used, from petroleum-fueled diesel engines that have been properly calibrated or rebuilt to the original engine manufacturer's specifications. TRT requests certification for the following two configurations of equipment: (1) Biodiesel fuel additive blended with diesel fuel (the blend is referred to as ``B20'') in combination with a particular exhaust system oxidation catalyst; and, (2) B20 and the catalyst, plus retarded fuel injection timing. Certification, if approved by the Agency, would apply to the combination of catalyst and biofuel supplied by TRT or its licensed distributors. The fuel B20 (alone) is not candidate for certification under this notification. One configuration of the candidate equipment, as applied to some engines, provides PM reductions greater than 25 percent and the other configuration does not. This is discussed further below. TRT has not provided life cycle cost information with the notification and has not requested to be certified as being available for less than the life cycle cost ceiling.
A key component of both configurations of the candidate equipment is use of biodiesel as an additive at a 20 percent by volume blend ratio with diesel fuel. Biodiesel is an ester-based fuel oxygenate derived from biological sources for use in compression-ignition (that is ``diesel'') engines. Biodiesel is the alkyl ester product of the transesterification reaction of biological triglycerides, or biologically-derived oils. Any biological oil source, such as vegetable oils, animal fats or used cooking oils and fats, can produce esters through this reaction. TRT has registered biodiesel under the Agency's Fuel/Fuel Additive Registration Program, which defines Twin Rivers biodiesel (marketed as ``EnviroDiesel<SUP>TM'' and ``EnviroDiesel Plus<SUP>TM'') as an alkyl ester containing C1-C4 alcohols and C6-C24 acids. The fuel handling procedure differs from that for diesel fuel only in that it requires mixing by the fuel distributor or bus operator of 20 percent by volume biodiesel with low-sulfur diesel fuel. TRT is a company created specifically for the production of biodiesel. A key component of both configurations of the candidate equipment is a particular oxidation catalyst-muffler unit (discussed further below) designed to replace the typical noise muffler in the exhaust system of applicable recipient engines. In a report included as an attachment to TRT's notification, it is indicated that the combination of B20 and the catalyst achieve greater PM reductions than with the catalyst alone. Improved PM reduction associated with that combination may be due to an apparent shift in the composition of total exhaust particulates, when using B20, toward a lower soot fraction and higher soluble organic fraction (SOF). It is the SOF portion of the exhaust particulates that an oxidation catalyst is most effective in reducing. The exhaust catalysts are to be matched to specific urban bus and engine configurations. Further, the maximum allowable exhaust pipe length between engine and catalyst is 108 inches. Exhaust system backpressure is designed to remain within the engine manufacturer's specified limits. The catalyst unit has no additional maintenance requirements for the life of the catalyst. The second configuration of the candidate equipment includes the retard of fuel injection timing in combination with B20 and the abovedescribed exhaust catalyst. All applicable engines using this second configuration and equipped with mechanical unit injection (MUI) would use a timing retard of four (4) degrees. All applicable engines using this configuration and equipped with electronically-controlled fuel injection would use a timing retard of one (1) degree. The notification states that timing is retarded by a shift of the timing sensor. The Agency requests comment and information concerning the reasonability of these timing specifications.
For its certification testing, TRT used catalytic muffler units that were manufactured by Engelhard Corporation and are the same formulation and configuration that is certified by the Agency for use in the urban bus program (see 60 FR 28402, dated May 31, 1995, for that certification). While an agreement is in place for Engelhard to supply TRT with catalysts, the physical specifications of the catalyst to be used in production are neither part of the[[Page 64053]]
TRT notification of intent to certify nor provided to TRT as part of that agreement. In general, the Agency has concerns when a certifier is not aware of the technical specifications of equipment it wants to certify and when the potential exists for a change in equipment specifications to adversely affect emissions reduction performance. Such a change in specifications may occur, for example, with a change in catalyst production which may not be known to the certifier. In a letter provided to the Agency, Engelhard states that it will notify both TRT and the Agency in the event of changes to specifications of the catalytic converter muffler provided to TRT. The specifications for the catalyst have been provided to the Agency as a confidential part of Engelhard's notification of intent to certify its CMX<SUP>TM catalyst muffler. A copy of this letter can be found in the public docket at the address indicated above. This provides the Agency with assurance that changes to catalyst specifications will be brought to the Agency's attention, and the Agency proposes to restrict certification for candidate TRT equipment to use of catalyst muffler units supplied by Engelhard and covered by Engelhard's certification, and require that use of catalysts supplied by any other supplier be the subject of a separate notification of intent to certify. TRT presents exhaust emission data from testing the candidate equipment configurations on three engines using the federal enginedynamometer test procedures of 40 CFR Part 86, as well as chassis dynamometer testing. A 1977 model year DDC 6V71N and 1988 model year DDC 6V92TA DDEC II were tested on engine dynamometers, and another 1988 model year DDC 6V92TA DDEC II was tested on a chassis dynamometer. The 6V71N engine was selected to represent a ``worst case'', with respect to PM, for most of the engines for which certification of the equipment is being sought, and also to represent engines equipped with MUI. Based on a pre-rebuild PM level for the 6V71N of 0.50, from the table in 40 CFR section 85.1403(c)(1)(iii)(A), TRT states that the 6V71N qualities as ``worst case'' for all two-stroke/cycle engines with the exception of the 1990 DDC 6L71TA. The 1988 6V92TA DDEC engines were tested to show the results of the biodiesel fuel on engines having electronic fuel control, and also to represent the ``worst case'' engine configuration for such engines, based on their ``pre-rebuild'' level of 0.31 g/bhp-hr. The notification states that the fuel used for testing, both the biodiesel and diesel, are representative of commercially available biodiesel and low-sulfur diesel fuels. Baseline testing was conducted after two of the test engines were rebuilt to the original engine manufacturer's configurations. A third engine had not been used prior to testing. Baseline testing was conducted using low sulfur test fuel having a maximum sulfur level of 0.05 weight percent. Subsequent testing of the engines was done after the candidate equipment was installed.
Table 1A below summarizes the emission levels from the engine dynamometer testing. Table 1B summarizes the chassis testing in terms of range of impact on exhaust emissions of the candidate equipment from three driving cycles. The driving cycles used for the chassis testing were the Central Business District, New York Bus Composite Cycle, and the Arterial Cycle. A report attached to TRT's notification provides specific emission rates measured for each driving cycle and equipment configuration. Table 2 summarizes, for each test engine, the changes in PM and NOXemissions with use of each configuration of the equipment. The reductions listed for the chassis testing include double weighting of the emission data from the Arterial Cycle, because TRT believes the resultant combination of the chassis driving cycles is more representative of the Agency's Urban Dynamometer Driving Schedule for Heavy-Duty Vehicles (40 CFR Part 86, Appendix I). Table 3 provides a summary of all engine models for which TRT intends the equipment to apply, and the associated percent reductions in PM emissions for these models, based on the test data. Table 4 summarizes the PM certification levels for each engine model for which certification is sought, based on reductions of Table 3 applied to the pre-rebuild levels established in the program regulations. Additional testing information is provided in reports from the facilities which conducted the emission testing (these reports are attachments to the notification). Table 1A.--Test Engine Emissions Gaseous and Particulate Smoke Engine --------------------------------------------------------------- Comment HC CO NOX PM ACC LUG Peak (3) g/bhp-hr (2) percent opacity Engine Dyno................................. 1.3 15.5 10.7 0.60 20 15 50 1988 EPA stds. 1977 6V71N MUI.............................. 0.86 3.18 11.72 0.282 1.2 1.8 1.8 Baseline (low S, 2D). 1977 6V71N MU............................... 0.38 0.86 12.11 0.166 0.9 1.7 1.7 B20 + cat. 1988 6V92TA DDEC II......................... 0.60 1.60 8.52 0.20 6.0 5.3 8.7 Baseline (low S, 2D). 1988 6V92TA DDEC II......................... 0.21 0.95 9.12 0.11 3.7 1.7 6.9 B20 + cat. Pollutant B20 + catalyst B20 + catalyst + 1.5 deg. retard HC..................................... -59 to -39................ -33 to +3 CO..................................... -85 to -54................ -38 to -19 NO<INF>X.................................... +4 to +8.................. -5 to -2 PM..................................... -56 to -22................ -46 to -7 \1\ Three different chassis driving cycles were used. Table 2.--Emissions Changes From Test Engines Configuration Per cent B20 CAT Timing retard PM change change Configuration and per Cent PM Reduction B20, cat + B20 + cat retard Table 4.--PM Certification Levels Equipment Configuration ------------------------- B20 + cat retard 6V92TA DDEC II Coach LDD0552FZL2 6V92TA DDEC II...... MDD0552FZG5 6V92TA DDEC II...... MDD0552FZL1 6V92TA DDEC II Coach NDD0552FZL0 6V92TA DDEC II Coach PDD0552FZL9