Control of Emissions of Air Pollution From New CI Marine Engines at or Above 37 kW

PART II

ENVIRONMENTAL PROTECTION AGENCY

40 CFR Part 94

[AMS-FRL-6196-3]

RIN 2060-AI17

Control of Emissions of Air Pollution From New CI Marine Engines

at or Above 37 kW

AGENCY: Environmental Protection Agency (EPA).

ACTION: Notice of Proposed Rulemaking.

-----------------------------------------------------------------------

SUMMARY: In this action, EPA is proposing an emission control program

for new compression-ignition marine engines rated at or above 37

kilowatts. The affected engines are used for propulsion and auxiliary

purposes in a wide variety of marine applications. The standards

proposed for these engines would require substantial reductions in

oxides of nitrogen and particulate matter emissions to correspond with

the next round of emission standards for comparable land-based engines.

The proposed standards are expected to provide a significant reduction

in oxides of nitrogen and particulate matter emissions from this

source. When combined with other mobile source emission control

programs, the program described in this action will help provide long-

term improvements in air quality in many port cities and other coastal

areas. Overall, the proposed program would provide much-needed

assistance to states facing ozone and particulate air quality problems,

which can cause a range of adverse health effects for their citizens,

especially in terms of respiratory impairment and related illnesses.

The persons potentially affected by this action are those who

manufacture new compression-ignition marine engines or marine vessels

or other equipment using such engines. Additional requirements apply to

companies that rebuild or maintain these engines.

DATES: EPA will hold a hearing on the proposed rulemaking on January

19, 1999. EPA requests comments on the proposed rulemaking by February

26, 1999. More information about commenting on this action and on the

public hearing and meeting may be found under Public Participation in

SUPPLEMENTARY INFORMATION, below.

ADDRESSES: Materials relevant to this proposal, including the Draft

Regulatory Impact Analysis, are contained in Public Docket A-97-50.

Additional materials relevant to EPA's earlier proposal, which was

published in 1994 and supplemented in 1996 but not finalized, can be

found in Public Docket A-92-28 (Control of Air Pollution; Emission

Standards for New Gasoline Spark-Ignition and Diesel Compression-

Ignition Marine Engines). Both of these dockets are located at room M-

1500, Waterside Mall (ground floor), U.S. Environmental Protection

Agency, 401 M Street, S.W., Washington, DC 20460. The docket may be

inspected from 8:00 a.m. until 5:30 p.m., Monday through Friday. A

reasonable fee may be charged by EPA for copying docket materials.

Comments on this proposal should be sent to Public Docket A-97-50

at the above address. EPA requests that a copy of comments also be sent

to Jean Marie Revelt, U.S. EPA, Engine Programs and Compliance

Division, 2000 Traverwood Dr., Ann Arbor, MI 48105.

The public hearing will be held at the National Vehicle and Fuel

Emissions Laboratory, 2000 Traverwood Drive, Ann Arbor, Michigan. The

public hearing will begin at 10 a.m. and will continue until all

testimony has been presented. People who wish to testify will be

requested to register on the day of the hearing. Time limits may be

imposed for each speaker, depending on the number of people who request

to testify. A transcript of the hearing will be placed in the docket.

Arrangements for copies may also be made directly with the court

reporter, on the day of the hearing. The court reporter may charge a

fee for this service.

For further information on electronic availability of this

proposal, see SUPPLEMENTARY INFORMATION below.

FOR FURTHER INFORMATION CONTACT: Margaret Borushko, U.S. EPA, Engine

Programs and Compliance Division, (734) 214-4334;

Borushko.M[email protected].

SUPPLEMENTARY INFORMATION:

Regulated entities

Persons or companies potentially regulated by this action are those

that manufacture or introduce into commerce new compression-ignition

marine engines and those that make vessels or other equipment using

such engines. Further requirements apply to companies that rebuild or

maintain marine engines. Regulated categories and entities include:

----------------------------------------------------------------------------------------------------------------

Category Examples of regulated entities NAICS code SIC code

----------------------------------------------------------------------------------------------------------------

Industry................................... Manufacturers of new marine diesel 333618 3519

engines.

Industry................................... Manufacturers of marine vessels.... 3366 3731

3732

Industry................................... Engine repair and maintenance...... 811310 7699

----------------------------------------------------------------------------------------------------------------

This list is not intended to be exhaustive, but rather provides a

guide for readers regarding entities likely to be regulated by this

action. To determine whether particular activities may be regulated by

this action, the reader should carefully examine the proposed

regulations, especially the applicability criteria in Sec. 94.1.

Questions regarding the applicability of this action to a particular

entity may be directed to the person listed in FOR FURTHER INFORMATION

CONTACT.

Obtaining Electronic Copies of the Regulatory Documents

The preamble, regulatory language and Draft Regulatory Impact

Analysis are also available electronically from the EPA Internet Web

site. This service is free of charge, except for any cost already

incurred for internet connectivity. The electronic version of this

proposed rule is made available on the day of publication on the

primary Web site listed below. The EPA Office of Mobile Sources also

publishes Federal Register notices and related documents on the

secondary Web site listed below.

1. http://www.epa.gov/docs/fedrgstr/EPA-AIR/ (either select desired

date or use Search feature)

2. http://www.epa.gov/OMSWWW/ (look in What's New or under the specific

rulemaking topic)

Please note that due to differences between the software used to

develop the document and the software into which the document may be

downloaded, changes in format, page length, etc., may occur.

[[Page 68509]]

Table of Contents

I. Introduction

II. Background

A. Air Quality Problems Addressed in the Proposed Rule

1. Ozone

2. Particulate Matter

3. Carbon Monoxide

4. Contribution of Marine Diesel Engines to NOX, HC,

PM, and CO Levels

B. Legislative and Regulatory History

1. Statutory Authority

2. Regulatory History

3. MARPOL Annex VI

4. State Activities

5. European Commission Action

C. Industry Characterization

1. Marine Diesel Engine Manufacturers

2. Commercial Vessel Builders

3. Recreational Vessel Builders

III. Engines Covered

A. General Scope of Application

B. Propulsion and Auxiliary Engines

C. Exemptions

1. Recreational Engines

2. Modified New Land-Based Engines

3. Other Exemptions

IV. Engine Categories

V. Description of Proposed Standards and Related Provisions

A. Standards and Dates

1. Marine Tier 2 Emission Limits

2. Marine Tier 3 Emission Limits

3. Interim Emission Limits

4. Total Hydrocarbons

B. Crankcase Emissions

C. Smoke Requirements

D. Alternative Fuels

E. Test Procedures

1. Duty Cycles

2. In-Use Testing

3. Test Fuel

4. Adjustable Parameters

5. Definition of Rated Speed

F. Not-to-Exceed Requirements

G. Voluntary Low-Emitting Engine Program

H. Durability

1. Useful Life

2. Warranty Periods

3. Deterioration Factors

4. Allowable Maintenance Intervals

5. Rebuilt Engines

6. Replacement Engines

I. Certification

1. Engine Family Definition

2. Emission Data Engine Selection

J SEA, Recall, and Production Line Testing

K. Miscellaneous Compliance Issues

L. Averaging, Banking and Trading Program

M. Special Provisions

1. Post-Manufacture Marinizer Provisions

2. Vessel Builder Flexibilities

N. Application of Provisions to Marine Diesel Engines Less than

37 kW

VI. Category 3 Engine Provisions

A. Emission Limits

B. Category 1 and 2 Engines Aboard Vessels Engaged in Foreign

Trade

VII. Technological Feasibility

A. Category 1 Engines

1. Development of Implementation Schedule

2. Development of Numerical Standards

3. Technological Approaches

4. Conclusions Regarding Technological Feasibility

B. Category 2 Engines

1. Development of Implementation Schedule

2. Development of Numerical Standards

3. Technological Approaches

4. Conclusions Regarding Technological Feasibility

B. Category 2 Engines

1. Development of Implementation Schedule

2. Development of Numerical Standards

3. Technological Approaches

4. Conclusions Regarding Technological Feasibility

C. Category 3 Engines

1. Rationale for Relying on MARPOL Annex VI Requirements

2. Technological Approaches

3. Conclusions Regarding Technological Feasibility

VIII. Projected Impacts

A. Environmental impacts (including noise)

1. Category 1 Engines

2. Category 2 Engines

3. Category 3 Engines

4. Other impacts

B. Economic impacts

1. Methodology

2. Engine Technologies

3. Estimated Costs

4. Aggregate Costs to Society

5. Sensitivity Analysis

C. Cost-effectiveness

1. Tier 2

2. Tier 3

3. Comparison to Other Programs

IX. Public participation

A. Comments and the Public Docket

B. Public Hearing

X. Administrative requirements

A. Administrative Designation and Regulatory Analysis

B. Regulatory Flexibility

C. Paperwork Reduction Act

D. Unfunded Mandates Reform Act

E. National Technology Transfer and Advancement Act

F. Protection of Children

G. Enhancing Intergovernmental Partnerships

H. Consultation and Coordination with Indian Tribal Governments

XI. Statutory Authority

List of Tables

Table 1 Comparison of Numerical Emission Limits: EPA's Nonroad Tier

1 Levels and MARPOL Annex VI Levels

Table 2 Locomotive Standards (line-haul only)

Table 3 Proposed European Emission Limits for Recreational Marine

Diesel Engines

Table 4 Engine Category Definitions

Table 5 Category 1 Engine Groups

Table 6 Proposed Tier 2 Marine Diesel Emission Limits and

Implementation Dates

Table 7 Land-Based Nonroad Tier 2 Emission Limits and

Implementation Dates

Table 8 Proposed Tier 3 Marine Diesel HC+NOX Emission

Limits and Implementation Dates

Table 9 Land-Based Nonroad Tier 3 Emission Limits and

Implementation Dates

Table 10 Voluntary Emission Standards

Table 11 Proposed Useful Life and Warranty Periods

Table 12 Category 1 Emissions Inventory

Table 13 Category 2 Emissions Inventory

Table 14 Category 3 Baseline and Projected Emissions Inventory

under Varying Implementation of MARPOL Annex VI controls

Table 15 Emission Inventory Impacts of the Proposed Rule

Table 16 Projected Incremental Costs by Power Rating

Table 17 Cost-Effectiveness of the Proposed Marine Tier 2 Standards

for HC and NOx

Table 18 Aggregate Cost-Effectiveness for the Proposed Marine Tier

2 Standards for HC and NOx

Table 19 Cost-Effectiveness of the Proposed Marine Tier 3 Standards

for HC and NOx

Table 20 Aggregate Cost-Effectiveness for the Proposed Marine Tier

3 Standards for HC and NOx

I. Introduction

Air pollution is a serious threat to the health and well-being of

millions of Americans, and imposes a large burden on the U.S. economy.

As discussed below, ground-level ozone and PM have been linked to

potentially serious respiratory health problems and environmental

degradation. Over the past two decades, emission control programs

established at the state and federal levels have significantly reduced

emissions from individual sources, and many of these sources now

pollute at only a fraction of their precontrol rates. These programs

have concentrated on reducing ground-level ozone levels, with a focus

on its main precursors, oxides of nitrogen (NOX) and

volatile organic compounds (VOCs).1 In addition, steps have

been taken to reduce airborne particulate matter (PM), which is also a

major air quality concern in many regions.

---------------------------------------------------------------------------

\1\ VOCs consist mostly of hydrocarbons (HC), including

nonmethane hydrocarbons (NMHC).

---------------------------------------------------------------------------

However, continued industrial growth and expansion of motor vehicle

usage threaten to reverse these past achievements. Today, many states

are finding it increasingly difficult to meet the current ozone and

particulate matter National Ambient Air Quality Standards (NAAQS) by

the deadlines established in the Clean Air Act (the

``Act'').2 In addition, even those states that are

approaching or have reached attainment of the current ozone and PM

NAAQS are likely to see these gains lost if current trends persist.

---------------------------------------------------------------------------

\2\ See 42 U.S.C. 7401, et seq.

---------------------------------------------------------------------------

National mobile source emission control programs have been

successful in reducing NOX, HC, and PM emissions

[[Page 68510]]

from new regulated engines. These programs have resulted in reductions

of more than 90 percent on a per-vehicle basis for new gasoline-fueled

passenger cars. Emissions from light-duty trucks have also been reduced

to very low levels. The more recent diesel engine programs, as

supplemented by new, more stringent requirements for highway and

nonroad diesel engines, will significantly reduce emissions from that

category as well. As a result of these programs, emission reductions on

a per-vehicle or per-engine basis have greatly offset emission

increases due to the rising mobile source population and usage rates.

Until now, EPA's effort to control emissions from marine sources

has been limited to outboard and personal watercraft engines and marine

diesel engines rated under 37 kW. EPA's analysis of national

NOX and PM levels suggests that marine diesel engines are a

considerable source of these pollutants. The inventory contribution of

marine diesel engines is presented under Background (Section II.A.4.),

and is described in greater detail in the Draft Regulatory Impact

Analysis. Consequently, emission controls for these engines may yield

important reductions in national NOX and PM inventories. At

the same time, designing an emission control program for marine diesel

engines at or above 37 kW poses certain challenges. The tremendous

range of engine sizes in this category, from small generators used on

board fishing or recreational vessels to large propulsion engines used

on board ocean-going vessels, suggests a need to set different

requirements for different groups of engines. In addition,

technological challenges inherent to nonroad diesel-cycle engine design

must be addressed.\3\ Traditional NOX control approaches

tend to increase PM emissions, and vice versa. However, methods to

achieve simultaneous NOX and PM control are being developed

for land-based diesel engines, and EPA believes similar solutions can

be applied to marine diesel engines due to similarities among the

engines. A more complete discussion of technology issues is presented

under Technological Feasibility (Section VII). Finally, the large

number of ship and boat builders and their relative inexperience with

emission control requirements suggest a need for a flexible

implementation process. A more detailed discussion of the

characteristics of this industry is included under Industry

Characterization (Section II.C.).

---------------------------------------------------------------------------

\3\ References to diesel-cycle engines, also referred to as

``diesel engines'' in this document, are intended to cover a

particular kind of engine technology, i.e., compression ignition

combustion. Compression-ignition engines are typically operated on

diesel fuel, although other fuels, such as compressed natural gas,

may also be used. This contrasts with otto-cycle engines (also

called spark-ignition or SI engines), which typically operate on

gasoline. The requirements set out in this notice are intended to

apply to all combustion-ignition engines.

---------------------------------------------------------------------------

In this document, EPA is proposing to extend the federal emission

control program to the marine segment of the nonroad industry by

proposing an emission control program for all new marine diesel engines

rated over 37 kW.\4\ The program described in this action follows EPA's

Supplemental Advance Notice of Proposed Rulemaking (Supplemental

ANPRM), published on May 22, 1998 (63 FR 28309), and the comments

received on that notice and other new information provide the framework

for its provisions.

---------------------------------------------------------------------------

\4\ This proposal is based on metric units. To convert to

English units, one kilowatt equals 1.341 horsepower.

---------------------------------------------------------------------------

II. Background

A. Air Quality Problems Addressed in the Proposed Rule

The emission standards proposed in this document will provide

important reductions of ground-level ozone and particulate matter (PM)

nationally, as well as carbon monoxide (CO) control. This section

summarizes the air quality rationale for these new emission standards

and their anticipated impact on marine diesel engines.

1. Ozone

Ground-level ozone is formed by complex photochemical reactions

involving HC and NOX in the presence of sunlight.\5\

According to a growing body of research, ground-level ozone can have

harmful physical effects on humans. It severely irritates the mucous

membranes of the nose and throat, which can lead to coughing and even

choking. It also impairs normal functioning of the lungs, and chronic

exposure may cause permanent lung damage. The risk of suffering these

effects is particularly high for children and for people with

compromised respiratory systems. Ground-level ozone has also been shown

to injure plants and building materials.

---------------------------------------------------------------------------

\5\ Ground-level ozone should not be confused with stratospheric

ozone, a protective layer of the upper atmosphere that filters the

sun's harmful ultraviolet rays.

---------------------------------------------------------------------------

Diesel engines contribute to ground-level ozone levels primarily

through their NOX emissions, which are a much higher portion

of total NOX+HC emissions than for most gasoline engines.

This is of significant concern not only because of ozone impacts but

also because NOX has important independent effects on human

health and general environmental conditions. NOX includes

several gaseous compounds that are lung irritants and can increase

susceptibility to respiratory illness and pulmonary infection.

NOX also contributes to the secondary formation of PM

(nitrates), acid deposition, and the overgrowth of algae in coastal

estuaries. Additional information on these environmental and health

effects may be found in EPA staff papers and air quality criteria

documents for ozone and nitrogen oxides. 6, 7,

8, 9

---------------------------------------------------------------------------

\6\ U.S. EPA, ``Review of National Ambient Air Quality Standards

for Ozone, Assessment of Scientific and Technical Information,''

OAQPS Staff Paper, EPA-452/R-96-007, 1996 (Air docket A-95-58).

\7\ U.S. EPA, ``Air Quality Criteria for Ozone and Related

Photochemical Oxidants,'' EPA/600/P-93/004aF, 1996 (Air Docket A-95-

58).

\8\ U.S. EPA, ``Review of National Ambient Air Quality Standards

for Nitrogen Dioxide, Assessment of Scientific and Technical

Information,'' OAQPS Staff Paper,'' EPA-452/R-95-005, 1995 (Air

Docket A-93-06).

\9\ U.S. EPA, ``Air Quality Criteria for Oxides of Nitrogen,''

EPA/600/8-91/049aF, 1993 (Air Docket A-93-06).

---------------------------------------------------------------------------

Acceptable levels of ground-level ozone have been set by EPA

pursuant to the Act. States are divided into areas for air quality

planning purposes, and these areas are categorized as to whether they

meet the current National Ambient Air Quality Standard for ozone by the

deadlines established in the Act.\10\ As of October, 1997 there are 59

areas designated as in ``nonattainment'' for ozone.

---------------------------------------------------------------------------

\10\ See 42 U.S.C. 7401, et seq.

---------------------------------------------------------------------------

The state and local governmental organizations charged with

designing and implementing emission control programs to bring these

areas into attainment have mounted significant efforts in recent years

to reduce ozone concentrations. Their state implementation plans,

combined with federal mobile source emission control programs, have

yielded encouraging signs of success. The main precursors of ozone,

NOX and VOCs (including HC), have been reduced in many

areas, and average ozone levels are beginning to decrease. However,

this progress is in jeopardy. EPA projects that emission increases that

accompany economic expansion will eventually outpace per-

[[Page 68511]]

source reductions in ozone precursors. Increases in the number of

sources, as well as increased use of existing sources, mean that even

full implementation of current emission control programs will fall

short of what will be needed to achieve and maintain ozone attainment.

By the middle of the next decade, the Agency expects that, without

additional controls, the downward trends in overall ground-level ozone

will be reversed. Consequently, it is important to develop new

strategies that improve, or at least maintain, the progress in ozone

reductions that have been achieved to date.

2. Particulate Matter

Particulate matter, like ozone, has been linked to a range of

serious respiratory health problems. Particulate matter is a collection

of small particles emitted by diesel engines. Many different organic

pollutants are adsorbed on these particles. The size and chemical

composition of particulate matter are the main reasons for concern

about the effects of PM on human health. Their small size increases the

likelihood that the particles will reach and lodge in the deepest and

most sensitive areas of human lungs. This can lead to severe lung

problems and increases susceptibility to respiratory infection, such as

pneumonia, aggravation of acute and chronic bronchitis, and asthma. It

can also lead to decreased lung function (particularly in children and

individuals with asthma) and alterations in lung tissue and structure

and in respiratory tract defense mechanisms. Additional information on

these effects may be found in an EPA staff paper and an air quality

criteria document for particulate matter.11, 12

---------------------------------------------------------------------------

\11\ U.S. EPA, ``Review of National Ambient Air Quality

Standards for Particulate Matter, Assessment of Scientific and

Technical Information,'' OAQPS Staff Paper, EPA-452/R-96-013, 196

(Air Docket A-95-54).

\12\ U.S. EPA, ``Air Quality Criteria for Particulate Matter,''

EPA/60/P-95/001aF, 1996 (Air Docket A-95-54).

---------------------------------------------------------------------------

Acceptable levels of PM have also been set by EPA. Currently, there

are 80 PM-10 nonattainment areas across the U.S. (PM-10 refers to

particles smaller than 10 microns in diameter.) As is the case with

NOX, levels of PM caused by stationary and mobile sources

are expected to rise in the future, not only because of the increase in

number of sources and activity levels of these sources, but also

because elevated NOX levels can lead to increased PM levels.

This is because NOX from diesel engines and other sources is

transformed in the atmosphere into fine secondary nitrate particles.

Secondary nitrate PM, consisting mostly of ammonium nitrate, accounts

for a substantial fraction of the airborne particulate in some areas of

the country. EPA believes that mobile sources contribute substantially

to the fraction of ambient PM that is generally considered

controllable.\13\ Consequently, EPA has been developing new mobile

source strategies to control PM emissions.

---------------------------------------------------------------------------

\13\ The largest fraction of ambient PM is attributed to

``miscellaneous'' and ``natural'' sources, including wind erosion,

wildfires, and fugitive dust, which are difficult or impossible to

control.

---------------------------------------------------------------------------

3. Carbon Monoxide

Along with NOX, HC, and PM, carbon monoxide (CO) is

another mobile source pollutant that is addressed by the program

proposed in this document. CO has long been known to have substantial

adverse effects on human health and welfare, including toxic effects on

blood and tissues, and effects on organ functions. CO has been linked

to fetal brain damage, reduced visual perception, cognitive functions

and aerobic capacity, and increased risk of heart problems for people

with heart disease. There are currently approximately 20 serious or

moderate CO nonattainment areas in the United States.

4. Contribution of Marine Diesel Engines to NOX, HC, PM and

CO Levels

EPA's inventory analysis suggests that marine diesel engines are a

significant source of NOX and PM emissions. This inventory

analysis, presented in more detail in the Draft Regulatory Impact

Analysis prepared for this action, suggests that marine diesel engines

currently contribute approximately one million tons of NOX

per year, representing 8.1 percent of mobile source NOX and

4.8 percent of total NOX emissions. Marine diesel engines

also contribute approximately 42,000 tons of PM per year, representing

4.4 percent of the directly emitted PM from mobile sources and 1.0

percent of total directly emitted PM emissions.\14\ In addition to

directly emitted PM, EPA estimates that, as a national average, marine

diesel engines contribute approximately 40,000 tons of PM in the form

of secondary nitrate particles, based on the estimated one million tons

of NOX emitted by these engines. In addition, emissions from

marine diesel engines tend to be concentrated in specific areas of the

country (ports, coastal areas, and rivers), and so local levels of

these pollutants can be much higher. Consequently an emission control

program that addresses NOX and PM emissions from marine

diesel engines can be an important tool toward the goal of reducing the

health and environmental hazards associated with these and other

pollutants.

---------------------------------------------------------------------------

\14\ Excluding erosion or fugitive dust.

---------------------------------------------------------------------------

The contribution of marine diesel engines to national HC and CO

levels is much less than for NOX and PM. EPA estimates that

marine diesel engines contribute less than two-tenths of one percent of

the national levels of these pollutants. Nevertheless, the program

being proposed in this rule includes limits for HC and CO emissions.

These limits will provide a small, positive, air quality benefit.

B. Legislative and Regulatory History

1. Statutory Authority

Section 213(a)(1) of the Clean Air Act directed the Agency to study

emissions from nonroad engines and vehicles to determine, among other

things, whether these emissions ``cause, or significantly contribute

to, air pollution that may reasonably be anticipated to endanger public

health or welfare.'' Section 213(a)(2) further required EPA to

determine whether the emissions of CO, VOC, and NOX found in

the above study significantly contribute to ozone or CO emissions in

more than one nonattainment area. With an affirmative determination of

significance, section 213(a)(3) requires the Agency to establish

emission standards regulating CO, VOC, and NOX emissions

from new nonroad engines and vehicles. EPA may also promulgate emission

standards under section 213(a)(4) regulating any other emissions from

nonroad engines that EPA finds contribute significantly to air

pollution.

The Nonroad Engine and Vehicle Emission Study required by section

213(a)(1) was completed in November 1991. 15 On June 17,

1994, EPA made an affirmative determination under section 213(a)(2)

that nonroad emissions are significant contributors to ozone or CO in

more than one nonattainment area. 16 In the same document,

EPA set a first phase of emission standards (``Tier 1 standards'') for

land-based nonroad diesel engines rated at or above 37 kW.

17 These requirements were recently augmented by a new

rulemaking that sets more stringent Tier 2 emission levels for new

land-based nonroad diesel engines at or above 37 kW as well as Tier 1

standards for nonroad diesel engines less than 37 kW. 18 EPA

has also initiated additional rulemakings to set

[[Page 68512]]

emission standards for other subgroups of nonroad engines, including

spark-ignition (SI, typically gasoline) engines less than 19 kW,

19 spark-ignition (SI, typically gasoline) marine engines

(outboards and personal watercraft), 20 and locomotives.

21 This action takes another step toward the comprehensive

nonroad engine emission control strategy envisioned in the Act by

proposing an emission control program for marine diesel engines at or

above 37 kW.

---------------------------------------------------------------------------

\15\ This study is available in docket A-92-28.

\16\ See 59 FR 31306, June 17, 1994.

\17\ Ibid.

\18\ See 63 FR 56967, October 23, 1998.

\19\ See 60 FR 34582 (July 3, 1995) for the final rule

establishing Tier 1 standards and 62 FR 14740 (March 27, 1997) for

the ANPRM discussing Tier 2 standards.

\20\ See 61 FR 52087 (October 4, 1996) for the final rule. EPA

did not set numerical emission standards for sterndrive and inboard

gasoline marine engines in this rule.

\21\ See 62 FR 6365 (February 11, 1997); the final rule was

signed December 17, 1997 and is available electronically (see

Section VI below).

---------------------------------------------------------------------------

2. Regulatory History

Numerical emission standards for marine diesel engines were

originally proposed in 1994, as part of a proposed rule for control of

emissions from both spark-ignition and compression-ignition marine

engines. 22 At that time, EPA had a limited understanding of

the marine diesel industry and, relying on the similarities between

land-based nonroad and marine diesel engines, proposed to apply the

same emission levels as those in the then just-finalized land-based

nonroad rule. The nonroad Tier 1 standards are set out in Table 1. EPA

proposed that these standards for marine diesel engines take effect

January 1, 1999 for engines less than 560 kW, and January 1, 2000, for

engines 560 KW and above. Although no upper limit on engine size was

proposed for application of these standards to marine diesel engines,

EPA requested comment on whether an upper limit should be established

above which the emission control program being developed concurrently

under the auspices of the International Maritime Organization (IMO)

should apply. The IMO is the Secretariat for the International

Convention on the Prevention of Pollution from Ships (that convention

is also referred to as MARPOL 73/78). Annex VI to that Convention,

adopted on September 27, 1997 (but not yet in force) contains, among

other provisions, requirements to limit NOX emissions from

marine diesel engines, but sets no limits for other engine pollutants

(i.e., HC, CO, PM). 23 A more detailed discussion of the

MARPOL 73/78 Annex VI NOX requirements is included in

Section II.B.3. below. Table 1 also contains the Annex VI

NOX limits, which would apply to new engines greater than

130 kW installed on vessels constructed on or after January 1, 2000, or

which undergo a major conversion after that date.

---------------------------------------------------------------------------

\22\ See 59 FR 55929 (November 9, 1994).

\23\ Other provisions of Annex VI include requirements for

ozone-depleting substances, sulfur content of fuel, incineration,

VOCs from refueling, and fuel quality. The United States has signed

Annex VI, but the Annex has not yet been forwarded to the Senate for

its advice and consent.

Table 1.--Comparison of Numerical Emission Limits: EPA's Nonroad Tier 1 Levels and MARPOL Annex VI Levels

------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------

Agency Engine speed HC (g/kW-hr) CO (g/kW-hr) NOX (g/kW-hr) PM (g/kW-hr)

------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------

EPA (Proposed).......................... All........................................................... 1.3 11.4 9.2................................... 0.54

MARPOL Annex VI (n =engine speed, rpm).. =130 rpm...................................................... None None 17.0.................................. None

130 rpmn2000 rpm........................ None None 45*n(-0.2)............................ None

n 2000............................................ None None 9.8................................... None

------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------

In response to the 1994 NPRM, several commenters requested that EPA

harmonize domestic emission standards for marine diesel engines to the

levels being then considered at the IMO, in effect, applying the draft

Annex VI limits domestically. Because the draft Annex VI standards

(which are the same as those finalized in 1997) were not as stringent

as the proposed domestic standards, this was a significant issue. On

February 7, 1996, EPA published a Supplemental NPRM to address this and

other concerns in more detail. 24 Specifically, EPA

identified and requested comment on three alternative harmonization

approaches: (1) Adopt the draft Annex VI NOX emission

standard instead of the standard proposed in the NPRM; (2) retain the

average NOX emission standard of 9.2 g/kW-hr proposed by EPA

and also adopt the MARPOL Annex VI NOX limit as a cap that

no engine could exceed; or (3) determine an appropriate engine speed or

engine power output cutoff point such that engines of high horsepower

and low and medium speeds would be subject to the draft Annex VI

NOX emission limits and engines of low horsepower and high

speed would be subject to the 9.2 g/kW-hr average standard proposed by

EPA with the 9.8 g/kW-hr Annex VI level as a cap that no engine could

exceed. EPA also sought comment on harmonizing the numerical emission

limits for other pollutants. Options considered were to drop, retain,

or alter the proposed standards for HC, CO, PM, and smoke.

---------------------------------------------------------------------------

\24\ See 61 FR 4600 (February 7, 1996).

---------------------------------------------------------------------------

While the development of the national marine rule and the

negotiations at the International Maritime Organization continued, EPA

began a new action for land-based nonroad diesel engines as part of a

new Agency initiative to reduce national NOX and PM

emissions from mobile sources. This action, subsequently finalized

September 27, 1998, sets more stringent standards for land-based

nonroad engines, known as Tier 2 standards (see Section V.A., below).

25 These Tier 2 standards will come into effect as early as

2001 for some engine categories. The rule also includes more stringent

Tier 3 standards, which will go into effect subject to a review to be

conducted in 2001. That review will be conducted through the normal

public rulemaking process. Finally, marine diesel engines less than 37

kW were included with their land-based counterparts in this diesel

land-based nonroad rule, with standards to come into effect as early as

1999 for Tier 1 and 2004 for Tier 2.

---------------------------------------------------------------------------

\25\ See 62 FR 50152 (September 24, 1997).

---------------------------------------------------------------------------

Also during this time, EPA finalized a rule setting emission

standards for new locomotive engines. 26 The locomotive

program consists of three separate sets of standards, with

applicability of the standards dependent on the date a locomotive is

first manufactured. The first set of standards (Tier 0) applies to

locomotives and locomotive engines originally manufactured from 1973

through 2001.

[[Page 68513]]

The Tier 0 standards will be phased in over a two-year period beginning

in 2000, and will apply at the time of each remanufacture (as well as

at the time of original manufacture for locomotives originally

manufactured in 2000 and 2001). The next set of standards (Tier 1)

apply to locomotives and locomotive engines originally manufactured

from 2002 through 2004. Such locomotives and locomotive engines will be

required to meet the Tier 1 standards at the time of original

manufacture and at each subsequent remanufacture. The final set of

standards (Tier 2) apply to locomotives and locomotive engines

originally manufactured in 2005 and later. Such locomotives and

locomotive engines will be required to meet the Tier 2 locomotive

standards at the time of original manufacture and at each subsequent

remanufacture. The numerical standards are contained in Table 2.

---------------------------------------------------------------------------

\26\ See 62 FR 6365 (February 11, 1997); the final rule was

signed December 17, 1997 and is available electronically (see

Section VI below).

Table 2.--Locomotive Standards

[Line-haul only]

----------------------------------------------------------------------------------------------------------------

Tier HC (g/kW-hr) CO (g/kW-hr) NOX (g/kW-hr) PM (g/kW-hr)

----------------------------------------------------------------------------------------------------------------

Tier 0.......................................... 1.3 6.7 12.7 0.80

Tier 1.......................................... 0.7 2.9 9.9 0.6

Tier 2.......................................... 0.4 2.0 7.4 0.27

----------------------------------------------------------------------------------------------------------------

The land-based nonroad diesel engine and locomotive rules led EPA

to reconsider its approach to the control of emissions from marine

diesel engines at or above 37 kW. Because of the similarities among

land-based nonroad, locomotive, and marine diesel engines, EPA began to

consider an alternative program for marine diesel engines based on the

technologies that will be used to meet the land-based requirements. As

a result, EPA did not take final action on marine diesel engines when

it finalized the original marine rule. 27 Instead, EPA

published an Advance Notice of Proposed Rulemaking advising interested

parties of the change in approach for marine diesel engine emission

controls and asking for comment on various aspects of the program under

consideration. The program proposed in this action follows from the

approach described in the ANPRM, the comments submitted by interested

parties, and information gathered by EPA in the meantime.

---------------------------------------------------------------------------

\27\ See 61 FR 52087 (October 4, 1996).

---------------------------------------------------------------------------

3. MARPOL Annex VI

In response to growing international concern about air pollution

and in recognition of the highly international nature of maritime

transportation, the parties to the International Maritime Organization

called upon the organization, in 1990, to develop a program to reduce

emissions from marine vessels. The IMO's Marine Environmental

Protection Committee (MEPC) was instructed to design a program, to

become a new Annex VI to the International Convention for the

Prevention of Pollution from Ships (MARPOL 73/78), that would achieve a

30 percent reduction in NOX and a 50 percent reduction in

SOX emissions when fully phased in. Requirements for ozone-

depleting substances, VOCs from cargo compartments on oil tankers,

shipboard incinerators, and fuel oil quality rounded out the scope of

the program. From the beginning, the engine-specific provisions of

proposed Annex VI covered only NOX emissions. No

restrictions on PM, HC, or CO emissions were considered. Reductions in

SOX emissions were to be pursued through limiting the sulfur

content of fuel.

After several years of negotiation, a final version of Annex VI was

adopted by the Member States of the IMO at a diplomatic conference on

September 26, 1997. However, pursuant to Article 6 of the Annex, it

will not go into force until fifteen States, the combined merchant

fleets of which constitute not less than 50 percent of the gross

tonnage of the world's merchant shipping, have ratified it. The Annex

in its entirety will acquire the force of law in the United States only

after the Senate (by a vote of two-thirds) concurs in the treaty and

the United States deposits its instrument of ratification.

Nevertheless, it is expected that ship owners will begin installing

compliant engines on relevant ships to comply with the dates set forth

in the Annex. Specifically, the NOX provisions contained in

Regulation 13 provide that each diesel engine with a power output of

more than 130 kW installed on a ship constructed on or after January 1,

2000, or that undergoes a major conversion on or after January 1, 2000,

must meet the NOX emission limits described in Table 1,

above. This specification of an effective date in Regulation 13 means

that, once the Annex goes into effect, Member States will be able to

require compliance by any ship constructed on or after January 1, 2000

or by any engine that undergoes a major conversion on or after that

date. In other words, once the Annex goes into effect, it will be

enforceable back to the dates specified in Regulation 13.

Two other features of Annex VI NOX requirements are

noteworthy. First, while the requirements set out in Regulation 13 are

expected to extend to all vessels used in the marine environment, a

special provision has been included in paragraph 1(b)(ii) to allow

Member States to set different standards for engines installed on ships

used domestically. EPA intends in this action to take advantage of this

provision by setting more stringent national requirements. Second,

Regulation 13 is augmented with a separate document, called the

NOX Technical Code, which sets out some compliance

requirements and test procedures. Through reference in the Annex, the

provisions of this Code are made mandatory on Parties to the Annex. A

more detailed discussion of the NOX curve and the

NOX Technical Code are included in the Draft Regulatory

Impact Analysis.

4. State Activities

Section 209 of the Act allows EPA to authorize California to

regulate emissions from new motor vehicles and new motor vehicle

engines, as well as nonroad engines with the exception of new engines

used in locomotives and new engines used in farm and construction

equipment rated under 130 kW.28 So far, the California Air

Resources Board (California ARB) has adopted requirements for three

groups of nonroad engines: (1) Diesel-and otto-cycle small off-road

engines rated under 19 kW; (2) new land-based nonroad diesel engines

rated over 130 kW; and (3) land-based nonroad recreational engines,

including all-terrain vehicles, snowmobiles, off-road motorcycles, go-

carts, and other similar vehicles. New

[[Page 68514]]

requirements that apply to new nonroad SI engines rated over 19 kW were

completed by CARB in October 1998. California ARB has also approved a

voluntary registration and control program for existing portable

equipment, and is currently considering an emission program for

recreational gasoline marine engines that may be more stringent than

the program finalized by EPA in 1996.

---------------------------------------------------------------------------

\28\ The Clean Air Act limits the role states may play in

regulating emissions from new motor vehicles and nonroad engines.

California is permitted to establish emission standards for new

motor vehicles and most nonroad engines; other states may adopt

California's programs (sections 209 and 177 of the Act).

---------------------------------------------------------------------------

EPA has been in consultation with California state officials and

various interest groups to pursue operational measures that would

reduce marine engine emissions without setting emission standards.

Under investigation are defined traffic lanes, restrictions on engine

operation while in port, and other measures that could be tailored to

the situation at each port.

5. European Commission Action

The European Commission has proposed emission limits for

recreational marine engines, including diesel engines. These

requirements would apply to all new engines sold in member countries.

The numerical emission limits, shown in Table 3, consist of the Annex

VI NOX limit for small marine diesel engines and the rough

equivalent of Tier 1 nonroad emission levels for HC and CO. The PM

limits, however, are more stringent than Tier 1 nonroad levels,

reflecting Europe's greater concern for the visual impacts of diesel

emissions. Emission testing is to be conducted using the ISO D2 duty

cycle for constant-speed engines and the ISO E5 duty cycle for all

other engines. At the current time, the EU has not initiated a separate

action for commercial marine diesel engines.

Table 3.--Proposed European Emission Limits for Recreational Marine

Diesel Engines

------------------------------------------------------------------------

Emission

Pollutant limit (g/kW-

hr)

------------------------------------------------------------------------

NOX....................................................... 9.8

PM........................................................ 0.14

HC........................................................ *1.5

CO........................................................ 5.0

------------------------------------------------------------------------

*Increases slightly with increasing engine power rating.

C. Industry Characterization

The two groups of companies most likely to be affected by the

proposed emission control program are engine manufacturers and vessel

manufacturers. This section contains a brief discussion of these

entities. A more complete discussion is included in the Draft

Regulatory Impact Assessment, which can be found in its entirety in EPA

Air Docket A-97-50.

1. Marine Diesel Engine Manufacturers

As discussed in Section IV, the proposed emission control program

applies to three categories of marine diesel engines. This discussion

reflects those categories.

Category 1 and Category 2 marine diesel engines are often derived

from land-based engines. Their production is often referred to as

marinization, meaning the land-based engine is modified for use in the

marine environment. Marinization can be a very complex process or may

be relatively simple. Depending on the degree of change to the base

engine, marinization can significantly affect the emission

characteristics of an engine. Some of the more complex changes

associated with marinization are performed by large engine

manufacturers. For these companies, marinization may involve a

significant redesign of their land-based product. A less intensive type

of marinization is performed by post-manufacturer marinizers. These

companies purchase a complete or semi-complete land-based engine from

an engine manufacturer and finish or modify it using specially designed

parts. The most basic type of marinization is performed by companies

that purchase a completed engine from an engine manufacturer and modify

it to make it compatible for installation on a marine vessel, without

changing the underlying design characteristics or engine calibration.

These companies are referred to in this rulemaking as engine dressers.

In contrast to the other marinization processes, these changes do not

typically affect the emission characteristics of the engine.

Category 3 engines have no land-based mobile source equivalents.

These engines are typically designed exclusively for marine purposes.

They are often designed for unique applications or unique vessels.

(a) Category 1 Engine Manufacturers. Total annual production of

Category 1 marine diesel engines in the U.S. is about 15,000 units per

year. Of these, commercial propulsion and auxiliary marine engines make

up about 30 percent and 10 percent, respectively, of the total

production. The remaining engines are used for propulsion in

recreational vessels. While the recreational engines are produced in

greater quantities, commercial propulsion and auxiliary engines

contribute more to air pollution on account of their much greater use.

Commercial applications for these engines are widely varied. Most

of these boats are relatively small and operate near the home port.

Primary examples of such vessels include fishing boats, crew boats,

tour boats, and small tugboats and ferries. Recreational vessels are

usually either yachts or are used for recreational fishing. These

recreational vessels may in some cases be used for commercial purposes.

Engine manufacturers produce the large majority of marine diesel

engines, with the remaining engines being produced by post-manufacture

marinizers. About a dozen engine manufacturers offer Category 1

engines, though Caterpillar, Cummins, and Detroit Diesel together sell

about 80 percent of all marine diesel engines. Fifteen or more

companies are either post-manufacture marinizers or engine dressers.

Most of these are small businesses with very low sales volumes.

Due to the wide range of companies and their operations, engine

maintenance and rebuild practices are far from uniform. Some are

serviced regularly by authorized distributors, others are maintained by

local for-hire mechanics. Some companies that operate vessels choose to

reduce expenses by keeping a staff of mechanics to conduct preventive

and routine engine maintenance and, in some cases, complete engine

rebuilds. Depending on the size of an operator's fleet, which may run

from one to several dozen vessels, and on the strength of the company,

there may or may not be an adequate ongoing investment in maintaining

engines to maximize long-term engine performance.

(b) Category 2 Engine Manufacturers. Large tugboats and fishing

boats are the principal applications for Category 2 marine engines.

These high-powered engines are used for carrying greater loads, a

greater degree of off-shore use and, in many cases, more intensive

operations. It is common for companies to own and operate small fleets

of these vessels. In addition, multiple Category 2 engines are commonly

used for auxiliary power on an ocean-going vessel.

Category 2 engines are derived from or use the same technology as

locomotive engines. Not surprisingly, Category 2 engines are produced

by the same companies that make locomotive engines, and the segment is

characterized by a very small number of manufacturers. General Motors

Electromotive Division (EMD) sells the greatest number of Category 2

engines, with additional sales from Caterpillar and a few other

companies (mostly from foreign manufacturers).

[[Page 68515]]

Post-manufacture marinizers play a role in producing Category 2

marine engines. For example, three authorized EMD distributors take on

the responsibility of marinizing engines, overseeing sales

distribution, and managing installation and service as needed. Unlike

post-manufacture marinizers for Category 1 engines, these companies

have sufficient volumes and diversified operations to the point that

they are not small businesses.

With prices approaching $1 million for a new engine, there is a

strong motivation to maintain and remanufacture engines in the field.

Preventive maintenance programs are common, often including extensive

ongoing diagnostics for oil quality, fuel consumption, and other engine

performance parameters. Engines are often completely remanufactured

every five years. Procedures have improved to the point that engine

durability on remanufactured engines is no different than on new

engines. Since engine remanufacturing costs only 20 to 30 percent as

much as buying a new engine, even twenty- or thirty-year-old engines

are frequently overhauled to provide dependable power.

(c) Category 3 Engine Manufacturers. Category 3 marine diesel

engines are the largest mobile source engines addressed by EPA. They

are similar in size to land-based power plant generators, and are used

primarily for propulsion of ocean-going vessels. There are currently no

U.S. manufacturers of Category 3 marine engines. The Agency, however,

has identified 22 foreign manufacturers of these engines, a large

fraction of which are located in Germany and Japan. In addition, of the

Category 3 engine manufacturers identified, only 12 produce engines of

their own design. The remainder of the manufacturers produce engines

under licensing agreements with other companies that control engine

design.

2. Commercial Vessel Builders

The industry characterization for the commercial marine vessel

industry was developed by ICF, Incorporated under contract with EPA. A

summary of their findings can be found in the Chapter 2 of the Draft

RIA. The full report is available from EPA Air Docket A-97-50. The

report makes a distinction between two broad groups of commercial

vessels, ``ships'' and ``boats,'' based on a vessel's basic dimensions,

mission, and area of operation.

(a) Commercial Ships. This category is comprised of large merchant

vessels, usually exceeding 120 meters (400 feet) in length, that engage

in waterborne trade or passenger transport. These ships tend to operate

in Great Lakes, coastwise, inter-coastal, noncontiguous, or

transoceanic routes. Principal commercial ship types are dry cargo

ships, tankers, bulk carriers and passenger ships. Passenger ships

include cruise ships and larger ferries. The large majority of

commercial ships are foreign-built. There are currently 18 major

shipbuilding facilities in the United States, most of which focus on

military construction.

(b) Commercial Boats. This category is comprised of smaller service

and industrial vessels that provide service to commercial ships,

industrial vessels, or barges or that perform specialized marine

functions. Commercial boats are found mainly in inland or coastal

waters. Principal commercial boat types are tugboats, towboats,

offshore supply boats, fishing and fisheries vessels, passenger boats,

and industrial boats. Passenger boats include crewboats, excursion

boats, and smaller ferries. The vast majority of boats used in the

United States are also built in the United States. In contrast to the

highly concentrated shipbuilding industry, there are several hundred

yards that build many different types of boats.

3. Recreational Vessel Builders

While not as numerous as commercial boat builders, there is still a

considerable number of recreational boat builders. EPA identified

approximately 75 boat builders, not including those that build

sailboats. Most of these companies also produce vessels that use

gasoline engines. In fact, diesel engines represent a small portion of

the overall product offerings for these companies. A small number of

recreational boat builders concentrate on diesel engine products. Most

companies, however, sell as few as one per month or even one per year.

The analysis shows that recreational boat building is concentrated in

coastal states with the largest presence in the state of Florida.

Recreational boat building relies more on serial production than

does commercial boat building. Users have little, if any, choice in the

mechanical features of the vessel and the engine specifically. This is

in part due to the way in which these boats are built. Recreational

boats are typically made of fiberglass to minimize vessel weight and to

facilitate planing. Fiberglass construction has the disadvantage of not

offering much flexibility for installing a different engine than that

which the vessel was designed to take. Also, planing requires a precise

match between the engine and its location in the vessel. Engines are

usually purchased from factory authorized distribution centers. The

boat builder provides the specifications to the distributor, which

helps match an engine for a particular application.

III. Engines Covered

A. General Scope of Application

The scope of application of the proposed emission control program

is broadly set by Sec. 213(a)(3) of the CAA, which instructs EPA to

promulgate regulations containing standards applicable to emissions

from those classes or categories of new nonroad engines and new nonroad

vehicles that are found to cause or contribute to ozone or carbon

monoxide concentrations in more than one nonattainment area. Generally

speaking, then, the proposed rule is intended to cover all new marine

diesel engines and new marine vessels that use those engines.

For the purpose of interpreting this scope of application for both

engines and vessels, EPA is proposing to generally extend the

definition of ``new'' contained in 40 CFR 89.2 to marine diesel engines

at or above 37 kW. Under that definition, an engine is considered new

until its legal or equitable title has been transferred and the engine

has been placed into service. Because the definition of new in 40 CFR

89.2 applies to both engines and equipment, its extension to the marine

sector would extend as well to vessels which, starting with the

implementation dates of the proposed emission limits, would be

considered new until their equitable or legal title has been

transferred to an ultimate purchaser.

EPA seeks comment on whether to augment this definition of ``new''

by following the approach used in the recently finalized locomotive

rule. That rule expands the definition of ``new'' to also include ``a

locomotives or locomotive engine which has been remanufactured, but has

not been placed back into service.'' \29\ This approach was designed to

respond to the very long useful lives of locomotives. Because

locomotive engines remain in service for as long as 40 or 50 years,

with periodic rebuilds, it was deemed advisable to require

remanufactured locomotives to meet a special set of emission standards,

depending on the date of their original manufacture. Because marine

diesel engines are also kept in service for very long periods of time,

such an approach would also lead to additional emission

[[Page 68516]]

benefits through the application of emission standards on engines that

have been put into service but that have subsequently been

remanufactured. In fact, this approach may be technologically easier to

apply to marine diesel engines than locomotives because of their

greater cooling potential. In addition, while not identical, the MARPOL

Annex VI provisions contain a similar requirement, which requires

engines to meet the NOX emission limits when the engine

undergoes a major conversion after January 1, 2000.

---------------------------------------------------------------------------

\29\ See 40 CFR 92.2.

---------------------------------------------------------------------------

At the same time, important obstacles may prevent application of

this approach to marine diesel engines. Setting emission limits for

remanufactured existing engines may be very disruptive to a large

number of small businesses. Also, unlike the railroad industry,

companies operating Category 2 marine diesel engines do not rely on a

small number of engine remanufacturers to work on their engines. In

fact, many of these operators employ their own mechanics to do all

maintenance and remanufacturing work. There is accordingly little

uniformity in remanufacturing practices across the industry. EPA would

need to conduct a major outreach effort to educate the industry about

the implications of such a requirement on their business. EPA seeks

comment on the feasibility and potential costs and benefits of

remanufacturing provisions for existing marine diesel engines. EPA also

seeks comment on its authority to establish such programs for each

marine engine category, including comment regarding whether marine

engines are ever remanufactured to ``as new'' condition, like

locomotive engines.

For the purpose of further clarifying the definition of ``new,'' 40

CFR 89.2 specifies that a nonroad engine, vehicle, or equipment is

placed into service when it is used for its functional purposes. For

the purpose of applying this criteria to marine diesel engine and new

vessels, EPA is proposing that a marine diesel engine is used for its

functional purpose when it is installed on a marine vessel. This

clarification is needed because some marine diesel engines are made by

modifying a highway or nonroad engine that has already been installed

on a vehicle or other equipment. In other words, the engine has been

transferred to an ultimate purchaser after it is used for its

functional purpose as a land-based nonroad engine (for example, on a

truck or a backhoe) and is therefore no longer new, but it is later

removed for marinization and installation on a marine vessel. While the

40 CFR part 89 requirements for land-based nonroad diesel engines do

not contain such a requirement, EPA believes it is reasonable to treat

these engines as new marine engines when they are installed on a

vessel. While the practice of marinizing used highway or nonroad

engines may be infrequent, it could become more common if these engines

are not subject to the standards in this proposal.

New marine engines are either made in the United States or imported

here. It should be noted that not all engines produced in the United

States will be subject to the proposed emission limits. Consistent with

other mobile source emission control programs, engines intended for

sale abroad would be exempt from the requirements.

Engines imported for use in the United States would be covered by

the proposed program whether they are imported as loose engines or

already installed on a vessel constructed elsewhere. All imported

engines would be required to have a certificate of conformity issued by

EPA before they could be entered into commerce in the United States,

subject to limited exemptions. In addition, EPA proposes to apply the

approach contained in its other on-highway and nonroad engine programs,

according to which any engine or vessel that is imported into the

United States that does not have a currently valid, unexpired

certificate of conformity and that was built after the effective date

of the applicable standards, would be considered to be new at the time

it is imported into the United States and would have to comply with the

relevant emission limits in effect at that time. Thus, for example, a

marine vessel manufactured in a foreign country in 2004 that is

imported into the United States in 2007 would be considered to be new,

and its engine would have to comply with the proposed emission limits

that would be in effect for MY2007. This provision is important to

prevent manufacturers from avoiding the emission requirements by

building vessels abroad, transferring their title, and then importing

them as used vessels.

Finally, while engines that are intended for export will not be

subject to the requirements of the proposed emission control program,

marine engines that are exported but that are subsequently re-imported

into the United States are intended to be covered. This would be the

case when a foreign company purchases marine engines manufactured in

the United States for installation on a vessel that will be

subsequently exported to the United States. It would also be the case

when a foreign company purchases marine engines manufactured in the

United States for dressing and subsequent re-exportation to the United

States. Engines that are intended for export but that will be re-

imported into the United States are intended to be subject to the

proposed rule at the time of manufacture, unless the vessel

manufacturer, engine dresser, or marinizer intends to re-certify the

engines as complying with the proposed emission limits before they

enter the United States. Consequently, foreign purchasers who do not

wish to recertify the engines will need to make sure they purchase

complying engines for those marine vessels or engines they intend to

subsequently offer for sale in the United States. Engines intended for

export and sale in a foreign country should be easily distinguishable

from complying engines because complying engines are required to be

labeled as such. Any person who introduces into commerce in the United

States a noncomplying engine that is intended for export and use in a

foreign country would be subject to civil penalties.

To determine when an engine or vessel will be considered

``imported'' for the purposes of determining compliance with the

proposed emission control program, EPA proposes to follow the approach

contained in the Harmonized Tariff Schedule of the United States

(HTSUS). According to HTSUS, vessels used in international trade or

commerce or vessels brought into the territory of the United States by

nonresidents for their own use in pleasure cruising are admitted

without formal customs consumption entry or payment of

duty.30 This approach is consistent with the Treasury

Department's ruling, which concluded that vessels coming into the

United States temporarily as carriers of passengers or merchandise are

not subject to customs entry or duty, but if brought into the United

States permanently they are to be considered and treated as imported

merchandise.

---------------------------------------------------------------------------

\30\ HTSUS (1994), Additional U.S. Note 1. In particular, cruise

ships, ferry boats, cargo ships, barges and ``similar vessels for

the transportation of persons or goods'' are duty free. HTSUS (1994)

8901.

---------------------------------------------------------------------------

Practically, the above discussion means that engines installed on

vessels flagged in another country that come into the United States

temporarily will not be subject to the proposed emission limits. This

approach is consistent with typical international practices, whereby

countries do not generally impose restrictions on the flag vessels of

other countries. In recognition of this practice, the numerous Member

States of the IMO

[[Page 68517]]

recently concluded an international agreement stipulating limits for

the emission of nitrogen oxides applicable to ships engaged in

international voyages. The above discussion also means that engines

installed on vessels that are brought into the United States

permanently would be subject to the proposed emission control program.

EPA seeks comment on this implication and seeks information concerning

the frequency with which this situation would occur.

B. Propulsion and Auxiliary Engines

The proposed scope of application is intended to cover all new

marine diesel engines at or above 37 kW. This universe of engines

includes both propulsion and auxiliary marine diesel engines.

Consistent with the definitions in 40 CFR 89, a propulsion engine is

intended to be one that moves a vessel through the water or assists in

guiding the direction of the vessel (for example, bow thrusters).

Auxiliary engines are intended to be all other marine engines.

In the final land-based nonroad rule, EPA determined that a

portable auxiliary engine that is used onboard a marine vessel would

not be considered to be a marine engine.31 Instead, a

portable auxiliary engine is considered to be a land-based auxiliary

engine and is subject to the requirements of 40 CFR 89. To distinguish

a marine auxiliary engine installed on a marine vessel from a land-

based portable auxiliary engine used on a marine vessel, EPA specified

in that rulemaking that an auxiliary engine is installed on a marine

vessel if its fuel, cooling, or exhaust system are an integral part of

the vessel or require special mounting hardware. All other auxiliary

engines are considered to be portable and therefore land-based.

---------------------------------------------------------------------------

\31\ See 63 FR 56967, October 23, 1998.

---------------------------------------------------------------------------

It has become clearer that the differences between marine auxiliary

engines and their land-based counterparts may be so small as to suggest

that these engines should not be treated differently at all. An

alternative approach is to consider all auxiliary engines to be the

same and subject them to the land-based nonroad diesel emission

requirements and implementation dates (40 CFR Part 89). These two

groups of engines are often technologically similar, if not identical,

and are dressed for their applications in the same way. The main

advantage of this alternative approach is that engine manufacturers

would not have to certify these engines twice, once for land-based

applications and once for marine applications. A consequence of

treating these auxiliary engines as land-based nonroad diesel engines

is that there would be some adjustments in emission limits,

implementation date, and other provisions. EPA seeks comment on whether

the land-based and marine distinctions are necessary for auxiliary

engines and on whether EPA should adopt the alternative approach

described above.

C. Exemptions

1. Recreational Engines

Marine diesel engines used in recreational and commercial

applications are different in several respects. Commercial vessels are

designed primarily to efficiently move cargo, either in their own hold

or by pushing or pulling other vessels. Consequently, they are

typically displacement vessels, which means the vessel is pushed

through the water. Optimal operations are more a function of hull

characteristics, which are designed to reduce drag, than engine size,

and these vessels can be powered by engines with power ratings

analogous to land-based applications. Commercial vessels are also often

heavily used, and their engines are designed to operate for as many as

2,000 to 5,000 hours a year at the higher engine loads needed to push

the vessel and its cargo through the water. In addition, these vessels

are often designed for specific purposes, and many characteristics,

including the choice of engine, are set by the purchaser.

Recreational vessels, in contrast, are designed primarily for

speed. To reach high speeds, it is necessary to reduce the surface

contact between the vessel and the water, and consequently these

vessels typically operate in a planing mode. Planing, in turn, imposes

two requirements on vessel design. First, the vessel needs to have a

very high power, but lightweight engine to achieve the speeds necessary

to push the vessel onto the surface of the water. Consequently,

recreational engine manufacturers have focused on achieving higher

power output with lighter engines (this is also referred to as high

power density). The tradeoff is less durability, and recreational

engines are warranted for fewer hours of operation than commercial

marine engines. The shorter warranty period is not a great concern,

however, since recreational vessels, and therefore their engines, are

typically used for fewer hours per year than commercial engines, and

spend much less time operating at higher engine loads.

Second, the vessel needs to be as light as possible, with vertical

and horizontal centers of gravity precisely located to allow the hull

of the vessel to be lifted onto the surface of the water. Consequently,

recreational vessel manufacturers have focused on designing very

lightweight hulls. They are typically made out of fiberglass, using

precisely designed molds. The tradeoff is a reduced ability to

accommodate any changes to the standard design. In other words,

purchasers are not given much choice as to the design of the vessel

and, more particularly, the engine that will be used to power it.

Recreational vessels are typically designed around a specific engine or

group of engines, and engines that are heavier or that are physically

larger cannot be used without jeopardizing the vessel's planing

abilities.

EPA has learned that many recreational engines already use the

types of technologies that will be necessary to reach the proposed

standards. These technologies are typically used to increase the power

density of recreational engines. EPA is concerned that redirecting the

impact of these technologies toward emission reduction may reduce

engine power density. This, in turn, means that recreational vessel

builders may have to resort to larger, heavier engines to achieve the

same engine power. They may also have to redesign their hulls, and

fiberglass molds, to accommodate larger, heavier engines. This can be a

costly requirement, since most vessel manufacturers destroy their

master hulls once the fiberglass molds are produced.

To allow more time to evaluate the potential impact of the proposed

emission limits on the recreational vessel industry, EPA is not

proposing to include recreational propulsion marine diesel engines in

the proposed emission control program. Instead, EPA intends to consider

requirements for those engines in a separate rulemaking. The Notice of

Proposed Rulemaking for that recreational marine diesel rule is

expected to be signed by November 23, 1999, and the Final Rule is

expected to be signed in October, 2000.

EPA considered various methods to distinguish commercial and

recreational marine diesel engines for the purpose of this exemption,

including relying on physical differences between recreational and

commercial engines or their warranty periods. These methods were found

to be unsatisfactory. Relying on physical differences between

recreational and commercial engines would be difficult, especially

since these engines are likely to become more similar as Tier 2

technologies are applied to commercial engines. Relying

[[Page 68518]]

on warranty periods would be difficult because not all engine

manufacturers have the same product ratings with the same warranty

periods. Imposing such requirements would unnecessarily impose a degree

of uniformity across the industry that may hinder engine design or

marketing strategies.

Consequently, EPA is proposing to take a more flexible approach and

is proposing to define a recreational marine engine as a marine

propulsion engine intended by the engine manufacturer to be installed

on a recreational vessel. In other words, a recreational engine would

be defined by the engine manufacturer. EPA is also proposing that

installation of a new recreational engine on a new nonrecreational

vessel would be prohibited, and that all recreational engines be

clearly labeled with language that specifies the engine is intended for

use only on recreational vessels. Specifically, EPA is proposing the

following label language:

THIS RECREATIONAL ENGINE DOES NOT COMPLY WITH FEDERAL MARINE

ENGINE EMISSION REQUIREMENTS FOR NONRECREATIONAL VESSELS.

INSTALLATION OF THIS ENGINE IN ANY NONRECREATIONAL VESSEL IS A

VIOLATION OF FEDERAL LAW SUBJECT TO CIVIL PENALTY.

Thus, EPA intends that recreational engines can be used only in

recreational vessels. It should be noted that the converse of this

provision is not true, and that EPA does not intend to prohibit the use

of a certified engine on a recreational vessel. In fact, EPA encourages

recreational vessel manufacturers to use certified engines due to the

beneficial impact it would have on the environment. It should also be

noted that this prohibition does not prevent someone from installing an

old marine engine in an old vessel.

EPA seeks comment on using a labeling requirement to distinguish

recreational engines from commercial engines for the purpose of the

exemption, and on whether this approach will be sufficient for

preventing the installation of noncertified recreational engines on

commercial vessels. EPA also seeks comment on whether a power or

displacement cutoff should be also specified, above which engines could

no longer be designated as recreational. For example, a power cutoff of

560 kW may be appropriate because larger engines are installed on

custom-built recreational vessels that are not subject to the same

design constraints as smaller serially-built fiberglass vessels.

For the purpose of the exemption, EPA is proposing to adopt the

definition of recreational vessel as that term is defined in 46 U.S.C.

2101. According to that definition, a recreational vessel is a vessel

(A) being manufactured or operated primarily for pleasure; or (B)

leased, rented or chartered to another for the latter's pleasure. EPA

further proposes that, for the purposes of part (B) of this definition,

the vessel cannot be leased, rented, or chartered for more than six

passengers. EPA is proposing that vessels for hire that can carry more

than six passengers, whether or not they ever actually do, be deemed

nonrecreational vessels. This is consistent with the definition of

recreational vessel for certain Coast Guard safety requirements (See 33

CFR 183.3, 33 CFR 175.3). At the same time, EPA is concerned that

including vessels used for hire in the definition of recreational

vessel may be inappropriate, since vessels used for hire may be used

far more extensively than recreational vessels owned by individuals

solely for their own pleasure. Therefore, EPA seeks comment on whether

the definition of recreational engine should be extended to vessels for

hire.

In addition, to avoid any ambiguities inherent in the term

``pleasure,'' vessels used solely for competition or used at any time

in any other way to generate income or revenue in any way not

associated with the hiring out of the vessel to other people for their

pleasure will not be considered recreational. In other words, if a boat

is used for both recreational and commercial purposes, it will be

considered a commercial vessel. Thus, for example, a vessel that is

used for several weeks a year for lobster fishing and at other times of

the year used for recreational purposes will not be considered to be a

recreational vessel for the purpose of the proposed program.

2. Modified New Land-Based Engines

A small segment of the marine diesel engine market consists of

companies that take a new, land-based engine and modify it for

installation on a marine vessel. However, unlike post-manufacture

marinizers (described in Section V.L.1., below), some of the companies

that modify an engine for installation on a marine vessel do not change

it in ways that may affect emissions. Instead, the modifications may

consist of adding mounting hardware and a generator or propeller gears.

It can also involve installing a new marine cooling system that meets

original manufacturer specifications and duplicates the cooling

characteristics of the land-based engine, but with a different cooling

medium (i.e., water). In many ways, these manufacturers are similar to

nonroad equipment manufacturers that purchase certified nonroad engines

to make auxiliary engines. This simplified approach of producing an

engine can more accurately be described as dressing an engine for a

particular application. Because the modified land-based engines are

subsequently used on a marine vessel, however, these modified engines

would be considered marine diesel engines, which would then fall under

the requirements proposed in this document.

To clarify the responsibilities of engine dressers under this rule,

EPA is proposing to exempt them from the requirement to certify engines

to the proposed standards, provided the following conditions are met.

(i) The engine being dressed, (the ``base'' engine) must be a

highway, land-based nonroad, or locomotive engine, certified pursuant

to 40 CFR 86, 40 CFR 89, or 40 CFR 92, respectively, or a marine diesel

engine certified pursuant to this part.

(ii) The base engine's emissions, for all pollutants, must be at

least as good as the otherwise applicable marine diesel emission

limits. In other words, starting in 2004, a dressed nonroad Tier 1

engine will not qualify for this exemption, since the more stringent

standards for marine diesel engines go into effect at that time.

(iii) The dressing process must not involve any modifications that

can change engine emissions.

(iv) All components added to the engine, including cooling systems,

must follow base engine manufacturer specifications.

(v) The original emissions-related label must remain clearly

visible on the engine.

(vi) The engine dresser must notify purchasers that the marine

engine is a dressed highway, nonroad, or locomotive engine and is

exempt from the requirements of 40 CFR 94.

(vii) The engine dresser must report annually to EPA the models

that are exempt pursuant to this provision and such other information

as EPA deems necessary to ensure appropriate use of the exemption.

EPA is proposing to consider any engine dresser that does not meet

these conditions to be an engine manufacturer, and the engine to be a

new marine diesel engine, and require their engines to be certified to

comply with the provisions of this proposed rule.

It should be noted that an engine dresser that violates the above

criteria could be liable under anti-tampering

[[Page 68519]]

provisions for any change made to the land-based engine that affects

emissions. The dresser could also be subject to a compliance action,

for selling new marine engines that are not certified to the required

emission standards. In addition, the base engine manufacturer could be

subject to a compliance action if the engine is found to be out of

compliance.

EPA seeks comments on three aspects of this proposed exemption.

First, EPA seeks comment on whether highway engines should be included

in the set of base engines that can be modified by an engine dresser

for marine application without needing further certification. EPA made

a previous decision not to allow certified highway engines to be used

in nonroad applications without recertifying. This decision was in

response to claims that highway engines may not be able to meet

applicable emission requirements on the steady-state test cycles

applicable to nonroad engines. EPA is nevertheless proposing to allow

engine dressers to modify certified highway engines without

recertifying them as marine engines, because EPA believes that engine

dressers would be unfairly penalized by the constraint that was

originally intended for manufacturers selling two versions of their own

engines. EPA requests comment on whether it is appropriate to include

highway base engines in this exemption.

Second, EPA seeks comment on how to ensure that exempted dressed

engines comply with the not-to-exceed requirements described in Section

V.F. of this proposal. The base engines certified under 40 CFR 86, 40

CFR 89, or 40 CFR 92 are not subject to these provisions at the present

time. Engines that are not subject to the off-cycle emission program

may not have test data demonstrating compliance with this requirement.

Finally, EPA seeks comment on whether land-based engines that are

credit users (those which have an FEL higher than the standard) should

be allowed to benefit from the exemption. According to the above

proposed criteria, the base engine's emissions must be at least as good

as the otherwise applicable marine diesel emission limits. However, it

may be the case that the base engine is a credit user, and that in fact

its emissions are not as good as the otherwise applicable marine diesel

emission limits, even though it is certified to the same or more

stringent emission limits. This is of concern because engine dressers

often prepare engines for marine vessels that are used in a particular

area of the country. This means that high-emitting dressed engines may

be concentrated in just a few port areas. In addition, it is unlikely

that enough credit generators will be dressed for marine purposes that

will offset the higher emitting credit users. The obvious solution to

this problem is to specify that land-based nonroad or locomotive

engines whose certification relied on the use of credits cannot benefit

from this exemption. However, it is not clear that engine dressers will

be able to identify these engines, or to modify their production

practices if they happen to rely heavily on them for their own

production. EPA seeks comment on this, as well as on any other

solutions that will ensure that engines dressed for marine applications

do not exceed the marine diesel emission limits.

3. Other Exemptions

EPA is proposing to extend other basic nonroad exemptions to marine

diesel engines. These include the testing exemption, the manufacturer-

owned exemption, the precertification exemption, the display exemption,

the national security exemption, and the export exemption described in

40 CFR 89 Subpart J. In addition, EPA seeks comment on an additional

exemption for racing and on the scope of the national security

exemption. It should be remembered that these exemptions are not

necessarily automatic, and that the engine or vessel manufacturer, or

ultimate engine owner, may need to apply for them. As part of its

approval, EPA may require exempted engines to be labeled.

With regard to the national security exemption, EPA is proposing to

apply the approach used in the Agency's existing land-based nonroad and

gasoline marine programs (40 CFR 89.908 and 40 CFR 91.1008). According

to this exemption, only marine engines used in vessels that exhibit

substantial features ordinarily associated with military combat, such

as armor and/or permanently affixed weaponry, and which will be owned

and/or used by an agency of the federal government with responsibility

for national defense, will be considered exempt from the proposed

emission control program. No request for an exemption would be

necessary for these engines. Thus, according to this approach, engines

used on vessels such as aircraft carriers, destroyers, and submarines

would automatically be exempt from the proposed program. EPA believes

extending the nonroad national security exemption to diesel marine

engines is appropriate because the vessels on which these engines are

used are designed for specific national security missions, and the

exemption will ensure that emission controls do not compromise the

ability of these vessels to achieve their military missions. However,

it is EPA's understanding that the Department of Defense, and the Navy

in particular, adopt emission control technology to the extent it is

practical and feasible.

It is EPA's understanding that other public vessels, such as some

vessels operated by the Coast Guard or Maritime Administration or

vessels used for general cargo purposes by the Navy or other armed

service branches, may not have features ordinarily associated with

military combat. Such vessels would not qualify for the automatic

exemption under the proposed national security exemption. EPA seeks

comment on the nature and uses of vessels in such fleets and on the

appropriate delineation of the national security exemption. EPA does

not believe that application of the emission control technology that

will be used to achieve the diesel marine Tier 2 emission limits will

hinder the design and use of these vessels. Nevertheless, there may be

situations in which an exemption from the emission controls may be

necessary. To address this possibility, manufacturers can request a

special national security exemption. A manufacturer requesting such an

exemption would be required to explain why the exemption is required,

and the request would need to be endorsed by an agency of the federal

government charged with responsibilities for national defense. EPA

requests comment on applying the land-based nonroad and gasoline marine

military exemption approach to diesel marine engines or whether these

engines are sufficiently different in application from land-based

military equipment as to require a different approach. If another

approach is more appropriate, EPA requests comment on what that

approach should be.

With regard to racing engines, EPA is proposing to allow an

exemption for marine diesel engines that are installed on vessels used

solely in competition. To limit the application of this requirement to

professional racing, EPA is also proposing that the racing exemption

may not be given to any vessel that is used for recreational purposes.

In other words, high-powered recreational vessels that are not used

solely in competition will not be eligible for the racing exemption.

The proposed approach is different from the approach used by EPA for SI

marine engines (40 CFR Part 91) and land-based nonroad diesel engines

(40 CFR Part 89). In those regulations, EPA defined ``used solely

[[Page 68520]]

for competition'' based on physical features of the vessel. However,

EPA does not believe that marine diesel vessels used solely for

competition will necessarily have physical features that are not found

on other high performance marine vessels. Thus, in this rulemaking, EPA

is proposing to interpret ``used solely for competition'' literally,

such that the exemption would apply only to engines that are, in fact,

used solely for competition. The Agency requests comment regarding

whether it should also use this literal approach for SI marine engines

or land-based nonroad engines.

IV. Engine Categories

The engines that are the subject of this action are very diverse in

terms of physical size, emission technology, control hardware, and

costs associated with reducing emissions. These differences make it

difficult to design one set of emission requirements for all marine

diesel engines. For example, numerical emission limits that may be

reasonable and feasible for a 37 kW engine used on an 5.5-meter (18-

foot) boat may not be reasonable or feasible for a 1,500 kW engine

installed on a tug or a 20,000 kW engine installed on an ocean-going

container ship. Similarly, numerical emission limits appropriate for

very large engines may be not be appropriately stringent for smaller

engines, requiring little or no emission reduction.

Consequently, it is necessary to divide marine diesel engines into

categories for the purposes of applying emission limits and duty

cycles. In developing these categories, EPA had two criteria. First,

the categories should allow EPA to take advantage of existing control

programs that apply to the base engines from which marine engines are

derived. Second, the categories should minimize category straddlers. In

choosing how to distinguish between groups of marine diesel engines,

EPA considered using rated power, rated speed, total displacement, and

several other factors. However, after reviewing the engine parameters

of the range of diesel engine models currently being produced, EPA

concluded that per-cylinder displacement was the best way to

distinguish engine groupings. Per-cylinder displacement is an engine

characteristic that is not easily changed and is constant for a given

engine model or series of engine models. More specifically, EPA is

considering the following categorization scheme, which is summarized in

Table 4. EPA requests comment on this categorization scheme.

Table 4.--Engine Category Definitions

----------------------------------------------------------------------------------------------------------------

Category Displacement per cylinder Basic engine type

----------------------------------------------------------------------------------------------------------------

1................................. Disp. 37 kW).

2................................. 5 disp. 20 liters Unique, ``Cathedral.''

----------------------------------------------------------------------------------------------------------------

EPA proposes to define Category 1 engines as those marine diesel

engines that are rated above 37 kW, but have a per-cylinder

displacement of less than 5 liters. This definition is intended to

break out the class of marine engines that are serially produced and

generally derived from land-based nonroad configurations or use the

same emission control technologies. These engines are typically used as

propulsion engines on recreational vessels as well as small commercial

vessels (fishing vessels, tugboats, towboats, dredgers, etc.) They are

also used as auxiliary engines on vessels of all sizes and

applications.

EPA proposes to define Category 2 engines as those marine diesel

engines with per-cylinder displacement at or above 5 liters and up to

20 liters. This category is intended to include engines that are of

similar size and configurations as locomotive engines and use the same

or similar emission control technologies. These engines are widely used

as propulsion engines in harbor and coastal vessels, and can be used as

auxiliary engines on ocean-going vessels and larger tugs.

EPA proposes to define Category 3 engines as those marine diesel

engines with a displacement at or above 20 liters per cylinder. These

are very large high-power engines that are used almost exclusively for

propulsion on vessels engaged in Great Lakes or trans-oceanic trade.

EPA is further proposing to divide Category 1 engines into several

subgroups. These subgroups are similar to the land-based nonroad diesel

engine subgroups, with one significant change: EPA is proposing to base

the marine subgroups on engine displacement rather than engine power.

EPA believes this is a more appropriate scheme for two reasons. First,

manufacturers sometimes offer different engine models that are the same

except for the number of cylinders. These engines may fall into

different power groupings by virtue of the added power from adding

cylinders. Second, marine engines are often available in a wider range

of power than their land-based counterparts. While it may be possible

to define wider power bands for marine diesel engine subgroups, it may

not be possible to do so without creating phase-in disadvantages for

particular companies, especially in comparison to their land-based

phase-in schedule. A displacement scheme should minimize these

inequities. Consequently, EPA is proposing a displacement approach to

defining engine groups, as described in Table 5.

Table 5.--Category 1 Engine Groups

------------------------------------------------------------------------

Approximate corresponding power band

from land-based nonroad rulemaking

Displacement (liters/cylinder) -----------------------------------------

kW hp

------------------------------------------------------------------------

Displ.kWhpdispl.kWhpdispl.kWhpdispl.kWhpdispl.kWhpdispl.560 hp750

------------------------------------------------------------------------

In selecting the displacement values corresponding with the nonroad

power ranges, EPA examined the engine displacement and power

characteristics of a wide range of existing engines. The listed

displacement values were selected to provide the greatest degree of

consistency with the established land-based nonroad engine power

groups. The wide range in power ratings for engines with a given per-

cylinder displacement, however, led to a high degree of overlap in the

attempted correlation between displacement and power rating. As a

result, some nonroad engine models that were spread across different

power groupings are brought together under a single displacement

grouping. This has the potential to move an engine model into a group

with somewhat more or less stringent requirements, but in almost all

cases there was sufficient overlap to avoid moving a family of engines

into an entirely new grouping. The observed overlap highlights the

benefit of relying on displacement for a simplified approach. This

should give manufacturers opportunity to more sensibly plan an R&D

effort to a family of engines that must meet a single set of

requirements with a common implementation date.

The most important aspect of defining sub-groups relates to which

engines are treated like nonroad diesel engines rated above 560 kW.

Emission limits and implementation dates for smaller marine engines are

relatively uniform; however, the biggest group of Category 1 engines

are subject to less stringent emission limits (for Tier 3) and have

more lead time, which makes it especially important to properly

separate engines. Investigation of engine models led to three key

observations. First, of the engines lines with per-cylinder

displacement between 2.5 and 5.0 liter, all had configurations with

available power ratings above 560 kW; several of these were much

greater than 560 kW. Second, except for one instance, all engines with

displacements less than 2.5 liter had configurations with available

power ratings below 560 kW; this means that the manufacturers of these

engines would have to meet the more aggressive requirements for some of

those engines. The only exception is the DDC 149 series engines, which

is being replaced with a new engine model. Third, the common practice

of bolting two marine engines together would often place the combined

engine artificially into the less stringent regime. For example, with

respect to emissions and performance, two six-cylinder 300 kW engines

bolted together would operate the same as each individual engine. Yet,

by doubling the power at the crankshaft, the engine would be subject to

less challenging requirements.

The net effect of changing to a displacement-based grouping is hard

to quantify. Somewhat greater emission reductions would likely result

for the reasons described above, though it is difficult to identify the

relative sales volumes of engines that would fall above and below the

threshold under both scenarios. The effect on costs is expected to be

small. As described above, no engines would be subject to the more

stringent standards that would not have a subset of the engine line

already subject to those same standards under a power-based grouping

arrangement. As a result, there should be no increase in R&D expenses.

Variable costs would be incurred for a greater number of engines, but

the costs analysis in the Draft RIA makes clear that variable costs

play a relatively small role in the overall cost impact of emission

requirements. The Draft RIA lists various engine models with their

displacement groups. EPA requests comment on this approach to defining

Category 1 engine groups. Also, EPA requests comment on whether it

would be appropriate to pursue redefinition of the nonroad diesel

emission standards into these displacement-based groupings as part of a

separate, future rulemaking.

V. Description of Proposed Standards and Related Provisions

In developing this proposal, EPA has developed a comprehensive

program to reduce emissions from marine diesel engines. This section

describes the proposed emission limits for Category 1 and Category 2

engines. It also sets out provisions that will ensure that engines

comply with the emission limits across all engine speed and load

combinations, as well as throughout their useful life. Proposed

requirements related to test procedures and fuel specifications are

also discussed, as well as several certification and compliance

provisions. Standards and related provisions for Category 3 engines are

described in Section VI, below.

A. Standards and Dates

1. Marine Tier 2 Emission Limits

The Agency's general goal in designing emission control

requirements for Category 1 and Category 2 marine diesel engines is to

develop a long-term program that will achieve significant emission

reductions. In developing such a program, the Agency is guided by

Sec. 213(a)(3) of the CAA, which instructs EPA to set standards for

nonroad engines that ``achieve the greatest degree of emission

reduction achievable through application of technology the

Administrator deems will be available for the engines or vehicles to

which such standards apply, giving appropriate consideration to the

cost of applying such technology within the period of time available to

manufacturers and to noise, energy, and safety factors associated with

the application of such technology.'' The Act also instructs EPA to

first consider standards equivalent in stringency to standards for

comparable motor vehicles or engines (if any) regulated under Sec. 202,

taking into consideration technological feasibility, costs, and other

factors.

The relevant engines regulated under Sec. 202 are on-highway truck

engines, both light-duty and heavy-duty. The most recent NOX

emission limits set by EPA for these engines range from approximately

2.5 g/kW-hr for heavy-duty trucks to less than 2.0 g/kW-hr for light-

duty trucks. After consideration, EPA determined that it is not

appropriate to extend the on-highway limits to diesel marine engines

for three reasons. First, these emission limits reflect a history of

emission control that is not shared by marine diesel engines, which are

currently uncontrolled, and it is not clear that marine diesel engines

can achieve such stringent emission

[[Page 68522]]

limits. In comparison, EPA estimates the baseline emission rates of

marine diesel engines to be approximately 10.5 g/kW-hr for the smaller

marine diesel engines. Second, the duty cycle demands for marine

engines are considerably different than those for on-highway trucks,

which must be reflected in any choice of emission limits for marine

engines. Finally, engines used in marine applications cover a much

broader power range. As described elsewhere in this preamble, the

marine engines covered by this rule vary in size from 37 kW to in

excess of 90,000 kW--much larger than any on-highway engines, which

vary from approximately 50 kW to 500 kW. It may not be possible for the

larger marine diesel engines to achieve the limits that were set for a

smaller universe of on-highway engines.

Instead of basing the proposed emission limits on on-highway

engines, EPA believes it is more appropriate to consider the standards

for land-based nonroad diesel engines already promulgated pursuant to

Sec. 213. This approach is favorable because the vast majority of

marine diesel engines are derived from or use the same technologies as

land-based engines. As described in the Draft Regulatory Impact

Assessment, manufacturers of marine diesel engines typically start with

a partially- or fully-completed land-based nonroad diesel engine or, in

some cases, a highway diesel engine, and adapt it for use in the marine

environment (this process is typically called ``marinization'').

EPA initially considered extending the land-based nonroad diesel

Tier 1 emission limits, as described in the NPRM for new gasoline

spark-ignition and diesel compression-ignition engines.\32\ These

limits are contained in Table 1, above. However, after further

consideration, EPA has concluded that those emission limits do not meet

the Sec. 213 criteria. Available data suggests that marine diesel

engines already perform at or near the NOX emission limits

(9.2 g/kW-hr). This is not surprising, given that the Tier 1 levels

required the application of very simple emission control technology,

primarily timing retard and better cooling. In addition, engine

manufacturers have been exploring better engine cooling for quite some

time in an effort to boost engine power.

---------------------------------------------------------------------------

\32\ See, 59 FR 55929, November 9, 1994.

---------------------------------------------------------------------------

Tier 2 nonroad technologies have been applied to marine diesel

engines with good results. As described in the Draft Regulatory Impact

Analysis, engine manufacturers participating in several California

demonstration programs experimented with applying Tier 2 technologies,

including electronic controls, better turbocharging, and raw-water

aftercooling, to various commercially used engines. These programs have

shown that NOX emissions can be reduced by 40 to 60 percent.

These results suggest that application of the land-based nonroad Tier 1

emission limits will not achieve the greatest degree of emission

reduction achievable, taking into account technological feasibility,

costs and other factors, as required by the Clean Air Act. Therefore,

EPA is not proposing to extend the land-based nonroad Tier 1 emission

limits to marine diesel engines.

At the same time, EPA is concerned about directly applying the

land-based nonroad Tier 2 emission limits to marine diesel engines, for

at least three reasons. First, the results obtained in the

demonstration projects may be better than could be expected over a more

general application of these Tier 2 technologies. Specifically, the

demonstration projects were carefully controlled programs, and the

engines were specially adapted for the participating vessels. These

engines may have seen better maintenance or fewer extremes in use than

typical marine diesel engines.

Second, manufacturers have indicated that there may be some

hardware problems that would have to be worked out before land-based

nonroad Tier 2 technologies can be applied to marine diesel engines.

For example, achieving Tier 2 emission limits will require a higher use

of raw-water aftercooling, which may present some problems for

commercial marine engines. As currently designed, these systems can

require more frequent maintenance, and may pose some reliability

problems. In addition, it is not clear whether split-housing

turbochargers can be used extensively with raw-water aftercooling,

since the temperature differences between the interior and exterior of

the turbocharger can cause material failure.

Finally, and perhaps most importantly, the demonstration projects

gathered emissions data primarily for NOX. It is not clear

what effect application of these technologies had on PM emissions. This

is an important concern because of the NOX/PM tradeoff (as

NOX emissions are decreased, PM emissions tend to rise due

to the change in combustion temperatures).

To address these concerns while still encouraging the use of land-

based nonroad technologies on marine diesel engines, EPA is proposing a

two-step approach for Category 1 and 2 marine diesel emission limits.

Reflecting the above-described concerns, this approach assumes less

than optimal transfer of land-based nonroad technologies to marine

engines in the short run. In the long run, however, this approach

assumes engine manufacturers will develop ways to fully optimize the

transfer of land-based nonroad Tier 2 and Tier 3 emission control

technologies to marine diesel engines. This two step approach will also

give engine manufacturers more time to resolve mechanical barriers that

prevent marine engines from more completely exploiting the water

cooling potential of the environment in which they operate (water).

Specifically, as described in the technological feasibility section

below and the Draft Regulatory Impact Assessment, greater use of raw

water and separate system aftercooling will permit marine engines to

greatly reduce NOX emissions. Taken as a whole, the proposed

emission limits are expected to yield the greatest degree of emission

reduction achievable through the application of technology that is

expected to be readily available during the time frame covered by the

proposal taking into account technological feasibility, costs and other

factors, as required by the Clean Air Act.

Table 6 contains the proposed emission limits for marine diesel

Category 1 and Category 2 engines. In the first step, which EPA is

calling Tier 2 due to the similarity to land-based Tier 2 emission

limits, EPA proposes a 7.2 g/kW-hr NOX+HC limit, to apply to

both categories of engines. Again, this limit is intended to result in

short-term NOX reductions while not requiring manufacturers

to completely resolve the transfer of land-based Tier 2 technologies to

marine engines. These marine Tier 2 emission limits are proposed to

apply beginning in 2004 for engines up to 5 liters per cylinder and

2006 for engines up to 20 liters per cylinder. The staggered dates

reflect the added complexities of applying these limits to larger

engines. The MARPOL Annex VI NOX limits are also provided in

this table for comparison.

[[Page 68523]]

Table 6.--Proposed Tier 2 Marine Diesel Emission Limits and Implementation Dates

----------------------------------------------------------------------------------------------------------------

Implementation

Subcategory HC+NOX g/kW-hr PM g/kW-hr CO g/kW-hr date

----------------------------------------------------------------------------------------------------------------

Power 37 kW 0.5 disp disp disp disp disp disp disp X only)

----------------------------------------------------------------------------------------------------------------

n 2000 rpm.......... 9.8........................... None None 1/1/2000

130 rpmn(-0.2).................... None .............. 1/1/2000

n X/PM tradeoff, the higher NOX

emission limit should ensure the feasibility of achieving the PM limits

as well. Diesel engines inherently have low CO emissions, and the

proposed limits are intended to serve as a cap.

EPA is proposing new requirements designed to ensure that the

standards are met during real world operation as well as under

laboratory tests (see Section V.F. ``Not-to-Exceed Requirements'').

According to these requirements, marine engines may not exceed the

applicable emission limits by more than 25 percent while the engine is

operated in any load/speed combination contained in a specified not-to-

exceed (NTE) zone. EPA believes that the technology listed above that

will be used to meet the proposed standards will be sufficient to meet

the combined emission limits and NTE requirements. While the NTE

transient operation requirements have an effect on PM emissions, this

is not expected to pose any design difficulties. Marine operations

typically have only limited transience and the NTE requirements are

designed so that a short transience can be averaged into a minimum

operating period.

EPA believes the proposed marine diesel emission limits set out in

Table 6 strike the appropriate balance, taking into consideration the

recently finalized Tier 2 emission limits that apply to the land-based

nonroad engines from which many if not most diesel marine engines are

derived and the special characteristics of marine diesel engines that

may make achievement of those limits difficult. EPA requests comments

on these proposed marine diesel Tier 2 limits. Specifically, it may be

the case that the barriers to applying land-based technologies to

marine diesel engines, including recreational engines, are smaller than

expected, and that the land-based nonroad emission control program is,

in fact, technologically feasible. In that case, extension of the land-

based programs would be the appropriate approach according to the

criteria set out in the Clean Air Act. The land-based Tier 2 emission

limits are contained in Table 7. EPA also seeks comment on whether the

superior cooling potential of marine diesel engines would permit even

lower emission standards for NOX and PM at an acceptable

cost.

Table 7.--Land-Based Nonroad Tier 2 Emission Limits and Implementation Dates

----------------------------------------------------------------------------------------------------------------

Implementation

Subcategory HC+NOX g/kW-hr PM g/kW-hr CO g/kW-hr date

----------------------------------------------------------------------------------------------------------------

Power 37 kW 0.5 disp disp disp disp disp disp disp X+HC limit, to apply to marine diesel engines up to 2.5 l/

cyl beginning in 2008. EPA believes this emission limit should be

achievable within the time available through more aggressive engine

cooling and use of electronic engine controls. At the same time, and

similar to the Tier 2 limits, there are uncertainties regarding the

transferability of land-based Tier 3 technologies to these marine

diesel engines. Because more complete information on the technologies

that will be used to achieve these limits for land-based engines will

not be available for several years, EPA intends to reconsider these

marine Tier 3 limits as part of a feasibility review, to take place in

2003. At that time, EPA will examine the extent to which the proposed

Tier 3 standards are technologically feasible and otherwise appropriate

under the

[[Page 68524]]

Clean Air Act. The marine diesel Tier 3 NOX+HC limits are

set out in Table 8.

Table 8.--Proposed Tier 3 Marine Diesel HC+NOX Emission Limits and

Implementation Dates*

------------------------------------------------------------------------

HC+NOX g/ Implementation

Subcategory kW-hr date

------------------------------------------------------------------------

Power 37 kW 0.5 disp

disp disp disp disp disp disp X g/ Implementation

Subcategory kW-hr date

------------------------------------------------------------------------

Power 37 kW 0.5 disp

disp disp disp disp 33 While the population of

engines in these areas may be smaller than land-based nonroad equipment

or locomotives, it is also the case that their use is much more

concentrated, being limited to port areas. In addition, many cities

with commercial ports are in nonattainment areas, and the second phase

emission limits will be an important tool to help them reduce local

ozone levels.

---------------------------------------------------------------------------

\33\ Category 1 and 2 marine diesel engines make up

approximately 6 percent of the NOX emission inventory for

San Diego, 5 percent for San Francisco and 2 percent for Los

Angeles-South Coast, Baltimore, and Chicago. See Commercial Marine

Vessel Contributions to Emission Inventories, Final Report,

Submitted by Booz-Allen & Hamilton, Inc., October 7, 1991.

---------------------------------------------------------------------------

EPA did not set Tier 3 emission limits for land-based nonroad

engines at or above 560 kW or for locomotives, due to the limited

cooling potential of those engines. These engines are typically

installed in relatively restrictive spaces, and are unable to take full

advantage of air-to-air cooling systems. However, EPA believes that

marine diesel engines at or above 2.5 l/cyl should be able to meet more

stringent Tier 3 emission limits because they can take advantage of the

medium in which they operate, water, to achieve better engine cooling

and additional NOX reductions. At the same time, the ability

of these larger engines to take full advantage of raw water

aftercooling or separate system aftercooling is complicated by the same

constraints that must be overcome for the smaller engines. To

accommodate concerns about overcoming this constraint, as well as

uncertainty over the transferability of more efficient cooling

technology from the smaller to the larger marine diesel engines, EPA

intends to review the Tier 3 emission limits for engines at or above

2.5 liters per cylinder as part of the 2003 Feasibility Review. EPA

seeks comment on the proposed Tier 3 limits for these engines,

concerning both their stringency and implementation dates.

Finally, EPA will also examine the need to set more stringent PM

limits as part of the 2003 Feasibility Review. Consideration of more

stringent PM standards will be a function of, but not depend

exclusively on, the ease with which engines are expected to reach the

NOX+HC limits, the extent to which the higher sulfur content

of marine diesel fuel can be accommodated, whether the land-based

nonroad diesel engine PM limits are revised as part of that category's

2001 feasibility review, and the cost of such limits.

Before making a final decision in the 2003 review, EPA intends to

issue a proposal and offer an opportunity for public comment on whether

the Tier 3 standards continue to be consistent with the requirements of

the Act and continue to be technologically feasible for implementation

according to the proposed schedule. Any Tier 3 PM standards would also

be proposed in such a notice. Following the close of the comment

period, EPA intends to issue a final Agency decision.

If by 2003 EPA finds the emission standards are not feasible

according to the proposed schedule, or are otherwise not appropriate

under the Act, EPA will propose changes to the program, possibly

including adjustments to the levels of the standards. The adjusted

standards may be more or less stringent than those already established,

including the possibility of a new emission standard for particulate

matter. The standards finalized in the rulemaking initiated by this

proposal would stay in effect unless revised by the subsequent

rulemaking procedure.

3. Interim Emission Limits

As noted above, EPA considered but rejected proposing land-based

nonroad Tier 1 emission limits to marine diesel engines. Such emission

limits would not be cost-effective because marine diesel engines often

already meet the Tier 1 emission limits, and a Tier 1 program would

simply impose a certification burden for minimal emission benefits.

At the same time, however, EPA is concerned about leaving these

engines uncontrolled until the implementation dates of the marine Tier

2 standards (2004 for engines up to 2.5 l/cyl and 2006 for engines

between 2.5 and 20 l/cyl). As noted above, these engines can be a

considerable source of NOX and PM emissions in port and

coastal areas, many of which are in nonattainment zones.

This problem may be alleviated, however, by the MARPOL Annex VI

emission control program. Regulation 13 of Annex VI to the

International Convention on the Prevention of Pollution from Ships

calls for engines installed on ships constructed on or after January 1,

2000, to meet emission limits similar in stringency to the land-based

nonroad Tier 1 limits. Although the Annex VI emission limits are not

enforceable until the Annex goes into effect (12 months after it is

ratified by 15 countries representing at least 50 percent of the gross

tonnage of the world's merchant shipping), it is expected that ship

owners will begin to comply with these emission limits in 2000 to avoid

future enforcement actions. According to Regulation 13(1)(b)(ii), the

Annex requirements will apply even to ships operated in domestic waters

unless a country takes action to the contrary. It is expected that the

MARPOL Annex VI program will act as a cap on NOX emissions,

since engine manufacturers will have to make

[[Page 68525]]

compliant engines available for installation on ships beginning January

1, 2000. At the same time, however, there is some concern about

compliance with these limits because they will not be enforceable until

the Annex goes into effect. In addition, the international inspection

program, when it goes into effect, will cover only engines installed on

ships at or above 400 gross tons.34

---------------------------------------------------------------------------

\34\ See Regulation 5, Surveys and Inspections, of the Annex.

---------------------------------------------------------------------------

EPA seeks comment on whether it is appropriate to rely on the

MARPOL Annex VI program as an interim cap on NOX emissions,

with no formal emission limits or certification program set by EPA.

Also, EPA seeks comment on how to verify that engine manufacturers are,

in fact, complying with the MARPOL Annex VI program prior to the

implementation date of Annex VI.

4. Total Hydrocarbons

EPA proposes to use total hydrocarbons (HC) rather than nonmethane

hydrocarbons in its emission standards for marine diesel engines. This

is consistent with locomotive standards but inconsistent with land-

based nonroad standards. Methane was considered to be removed from the

regulated pollutants since it is significantly less reactive than other

hydrocarbons in the formation of ozone. However, for diesel engines,

methane only makes up about two percent of the total hydrocarbons. In

addition, HC generally makes up less than five percent of the combined

HC+NOX from a marine diesel engine. The combination of these

two factors renders the methane fraction of the exhaust insignificant

when compared to the significant digits in the proposed

HC+NOX standard.

The advantage of using total hydrocarbons rather than nonmethane

hydrocarbons in the proposed standard is that it simplifies the

emission measurement. To determine NMHC, both HC and methane must be

measured. Methane is generally measured by speciating total

hydrocarbons using a gas chromatograph, which can be time consuming and

costly. In addition, by using total hydrocarbons for the standard for

all marine diesel engines, the standards are consistent for Category 1

and Category 2.

B. Crankcase Emissions

EPA is proposing to require that all marine diesel engines either

have closed crankcases (where blowby gases are routed into the engine

intake air stream), or route all blowby gases into the engine exhaust

stream for inclusion in all exhaust emission measurements.

Manufacturers would be allowed flexibility for routed blowby gases in

in-use configurations, provided that the blowby gases could be readily

routed into the exhaust for any in-use test. This approach is similar

to the approach used by EPA for locomotives. The purpose of this

proposed requirement is to provide manufacturers the incentive to

reduce crankcase emissions to the maximum extent possible, or to

eliminate them all together.

C. Smoke Requirements

EPA is not proposing smoke requirements for marine diesel engines.

Marine diesel engine manufacturers have stated that many marine diesel

engines, even though currently unregulated, are manufactured with smoke

limiting controls at the request of the engine purchasers. Users seek

low smoke emissions both because they dislike the residue smoke

emissions leave on decks and because they can be subject to penalties

in ports that have smoke emission requirements. In many cases, marine

engine exhaust gases are mixed with water prior to being released. This

practice reduces the significance of smoke emissions since smoke

becomes significantly less visible. Moreover, the Agency believes that

the PM standards being proposed here will have the effect of limiting

smoke emissions as well. EPA requests comment on these views and,

specifically, on whether there is a need at this time for additional

control of smoke emissions from Category 1 marine engines, and if so,

what the appropriate limits should be.

If a smoke limit is desirable, EPA also requests comment on what

the test procedure should be. There is currently no test procedure that

can be used to measure compliance with a smoke limit. Most propulsion

marine engines operate over a torque curve governed by the propellor.

Consequently, a vessel with an engine operating at a given speed will

have a narrow range of torque levels. Some large propulsion marine

engines have variable-pitch propellers, in which case the engine

operates much like constant-speed engines. It should be noted, however,

that ISO is working on a proposal for marine diesel engine smoke test

procedures. A copy of a recent draft is being placed in the docket for

this rulemaking. As this procedure is finalized by ISO, and emission

data become available, EPA may review the issue of smoke requirements

for all marine diesel engines. EPA requests comment on this overall

approach to smoke emissions from marine diesel engines, as well as

comment on the draft ISO procedures.

D. Alternative Fuels

EPA has determined that the proposed standards should apply to

marine diesel engines, without regard to the type of fuel that they

use. This is consistent with nonroad diesel engine regulations of 40

CFR part 89. It is also generally consistent with the locomotive

regulations; however, the locomotive regulations apply even more

broadly because they also include spark-ignited engines. EPA recognizes

that few, if any, alternative-fueled marine engines are currently being

manufactured, but believes that it is appropriate to make clear to

manufacturers what standards will apply to such engines should they be

produced.

The broad applicability of the proposed standards raises two

potential issues. The first issue is related to the form of the HC

standards. In its regulation of highway vehicles and engines (59 FR

48472, September 21, 1994), the Agency determined that it is not

appropriate to apply total hydrocarbon standards to engines fueled with

natural gas (which is comprised primarily of methane), but rather that

nonmethane hydrocarbon (NMHC) standards should be used. Thus, EPA is

setting NMHC+NOX standards for compression-ignition natural

gas-fueled marine engines. These NMHC+NOX standards are

numerically equivalent to the HC+NOX standards proposed for

diesel engines. Similarly, EPA has determined that alcohol-fueled

engines should be subject to HC-equivalent (HCE) standards instead of

HC standards (54 FR 14426, April 11, 1989). HC-equivalent emissions are

calculated from the oxygenated organic components and non-oxygenated

organic components of the exhaust, summed together based on the amount

of organic carbon present in the exhaust. (The reader is referred to

the April 11, 1989 final rule for more information regarding the

determination of HC-equivalence.) EPA is proposing these approaches

because it has previously determined that these approaches will result

in the most equivalent stringency for all fuel types.

The second issue raised by the regulation is related to the need

for slightly different test procedures for alternative-fueled engines.

This issue is being resolved in this rulemaking by referencing the test

procedures found in 40 CFR Parts 89 and 92, both of which include

flexibility for testing alternative-fueled engines. EPA requests

comment

[[Page 68526]]

on whether more specific regulation is needed for marine engines.

E. Test Procedures

For this marine regulation, EPA is proposing to use previously

established test procedures for diesel nonroad engines. Specifically,

EPA is proposing that Category 1 marine engines be tested using the

land-based nonroad test procedures of 40 CFR Part 89, and that Category

2 marine engines be tested using the locomotive test procedures of 40

CFR Part 92. There are two reasons for using this approach. First, most

manufacturers of marine compression-ignition engines also manufacture

land-based engines and will be equipped to test engines using these

test procedures. Second, marine compression-ignition engines are

fundamentally similar to their land-based counterparts, and it is

therefore appropriate to measure their emissions in the same way. At

the same time, some changes are necessary, EPA is proposing the

modifications to these test procedures described below.

1. Duty cycles

The duty cycle used to measure emissions is intended to simulate

operation in the field. Testing an engine for emissions consists of

exercising it over a prescribed duty cycle of speeds and loads,

typically using an engine dynamometer. The nature of the duty cycle

used for determining compliance with emission standards during the

certification process is critical in evaluating the likely emissions

performance of engines designed to those standards.

To address operational differences between engines, EPA is

proposing different duty cycles for different types of compression-

ignition marine propulsion engines. EPA is proposing that propulsion

engines that operate on a fixed-pitch propeller curve be certified

using the International Standards Organization (ISO) E3 duty cycle.

This is a four-mode steady-state cycle developed to represent in-use

operation of marine diesel engines on vessels 24 meters in length and

larger. The four modes lie on an average propeller curve based on the

vessels surveyed in the development of this duty cycle. Another duty

cycle, ISO E5, was developed to represent in-use operation of smaller

marine diesel engines; this cycle is similar to the E3 except that an

idle mode is added and the cycle is more heavily weighted towards lower

power modes. The E3 is designed for engines used to propel vessels

greater than 24 meters in length while the E5 is designed for engines

used to propel vessels less than 24 meters in length. The

attractiveness of the E3 duty cycle is that, according to EPA's

inventory analysis, the majority of HC+NOX emissions from

marine diesel engines are generated by engines on vessels more than 24

meters in length. By choosing a single cycle to represent all

propeller-curve marine diesel engines, EPA hopes to reduce

certification burdens for marine engines that are used in vessels both

over and under 24 meters in length.

EPA is proposing that fixed-speed marine propulsion engines with

variable-pitch propellers be certified on the ISO E2 duty cycle. This

duty cycle is also a four-mode steady-state cycle. It uses the same

power and weighting factors as the E3 cycle, but the engine is operated

in each mode at rated speed.

EPA is also proposing that variable-speed marine propulsion engines

with variable-pitch propellers be certified on the ISO E2 duty cycle.

These engines are designed to operate near their power curve to

maximize fuel efficiency. In general, these engines will operate at a

constant speed except when maneuvering in port. Because of the expense

of the system, variable-speed engines are rarely used with variable-

pitch propellers. ISO does not have a test duty cycle specifically

designed for these engines. However, because most of their operation is

at constant speed, EPA is proposing that these engines certify using

the E2 duty cycle. EPA proposes that the speed setting for testing

should coincide with the speed setting at which the engine would spend

most of its time in use.

For auxiliary engines, EPA is proposing that constant-speed

auxiliary engines be certified to the ISO D2 duty cycle and that

variable-speed auxiliary engines be certified to the ISO C1 duty cycle.

These duty cycles are consistent with the requirements for land-based

nonroad diesel engines. More detail on the proposed duty cycles is

contained in the Draft Regulatory Impact Analysis (Draft RIA)

associated with this proposal. EPA requests comment on the

appropriateness of the proposed duty cycles.

Under the provisions of the land-based nonroad rule, engine

manufacturers have the option to petition for their marine engines to

be included in land-based engine families. EPA is not proposing this

flexibility for propulsion marine engines because the ``not-to-exceed''

provisions described below require the use of the marine duty cycles.

For larger marine engines, conventional emission testing on a

dynamometer becomes more difficult because of the size of the engine.

Often engine mock ups are used for the development of these engines

where a single block is used for many years and only the power assembly

is changed out. EPA proposes that for Category 2 engines, certification

tests may be performed on these engine mock ups provided that their

configuration is the same as that of the production engines. In

addition, for larger Category 2 marine engines, EPA requests comment on

whether or not single-cylinder tests should be allowed for

certification testing. Assuming that each cylinder in an engine is

equivalent, a single-cylinder test should give the same brake-specific

emission results as a full engine test.

2. In-Use Testing

As with its other federal mobile source programs, EPA retains the

authority to perform in-use testing on marine engines to ensure

compliance in use. This testing may include taking in use marine diesel

engines out of the vessel and testing them in a laboratory, as well as

field testing of in use engines in the vessel, in a marine environment.

EPA's proposal specifies the equipment and related procedures for use

in laboratory based testing. EPA is not at this time, however,

specifying similar provisions for field testing. EPA expects that the

capabilities of field testing equipment will increase over time, and it

is better to allow this to occur without attempting to pick testing

technologies at this time, or interfere with this development process.

Field testing data will be used by EPA in two ways. First, it may

be used as a screening tool, with follow up laboratory testing where

appropriate. Second, it may be used directly as a basis for compliance

determinations, when the field testing itself provides reliable

information from which conclusions can be drawn regarding what

laboratory based emissions levels would be. The probative value of

field test data is expected to increase over time, as the capabilities

of field testing equipment are developed. The flexibility in testing

that these approaches provide will allow EPA to most efficiently

conduct in use testing, and will also address those situations where it

is physically or otherwise impossible to remove an engine from a marine

vessel for testing in a laboratory.

For compression-ignition marine engines that expel exhaust gases

under water or mix their exhaust with water, EPA proposes to require

that the engines be equipped with an exhaust sample port where a probe

can be inserted for in-use exhaust emission testing. It is important

that the location of this port

[[Page 68527]]

allow a well mixed and representative sample of the exhaust. The

purpose of this proposed provision is to simplify in-use testing. EPA

requests comment on the proposed in-use testing provisions.

3. Test Fuel

Section 206(h) of the Clean Air Act requires EPA to ensure that the

test procedure, including the test fuel, adequately represent in-use

operation. To facilitate the testing process, EPA specifies a test fuel

that is intended to be representative of in-use fuels. Engines would

have to meet the standard on any fuel that meets the proposed test fuel

specifications, with one modification as described later. This section

describes the test fuel EPA is proposing for Category 1 and Category 2

engines. This test fuel is to be used for all testing associated with

the regulations proposed in this document, to include certification,

production line and in-use testing, as well as any NTE testing.

EPA is proposing that the recently finalized test fuel

specifications for nonroad diesel engines be applied, with a

modification to the sulfur specification as described later, to both

Category 1 and 2 marine diesel engines. EPA believes that largely

adopting the nonroad fuel will simplify development and certification

burdens for marine engines that are developed from land-based

counterparts. The proposed test fuel for marine diesel engine testing

has a sulfur specification range of 0.03 to 0.80 weight-percent (wt%),

which covers the range of sulfur levels observed for most in-use fuels.

Manufacturers are generally responsible for ensuring compliance with

the emission standards using any fuel within this range. Thus, they

will be able to harmonize their marine test fuel with U.S. highway

(35 Using ASTM

specification D 2069 as a guide, EPA considered choosing an upper limit

of 1.5 wt% sulfur. Although 1.5 wt% may be appropriate based on the

ASTM specification, EPA is proposing that this upper limit on sulfur

content be 0.8 wt% because PM can not accurately be measured using the

proposed testing procedures using fuels with a sulfur content higher

than 0.8 wt%.36 EPA requests comment on whether it is

appropriate to limit the test fuel specification in this way due to

this testing constraint.

---------------------------------------------------------------------------

\35\ ``Final Report: 1996 American Petroleum Institute/National

Petroleum Refiners Association Survey of Refining Operations and

Product Quality'' suggests that actual marine diesel fuels may have

sulfur contents somewhat higher than general nonroad diesel fuels.

ASTM specification D 2069 includes a specification for general

purpose marine distillate fuel with a maximum sulfur content of 1.5

wt%.

\36\ ``Exhaust Gas Emission Measurements: A Contribution to a

Realistic Approach,'' D. Bastenhof, dieselMAC, May, 1995.

---------------------------------------------------------------------------

The proposed PM standards were largely determined to be feasible

based on the feasibility of the corresponding standards for land-based

nonroad and locomotive applications, which have a 0.4 wt% sulfur upper

limit for the test fuel. Since PM emissions are somewhat fuel sulfur-

dependent, EPA does not believe that it is appropriate to require

compliance with the PM standards using fuel with a sulfur content above

0.4 wt%. It is for this reason that EPA is proposing to allow a

correction of PM emissions for tests that are run using fuel with a

sulfur content greater than 0.4 wt%. Thus, the measured PM emissions

for any test performed using fuel with a sulfur content of greater than

0.4 wt% would be corrected to the level that would have been measured

if the fuel had a sulfur content of 0.4 wt%. The proposed correction

method is that used for land-based nonroad engine testing. EPA requests

comment on whether this correction method is accurate and appropriate

for this application.

It is EPA's intent that engines be designed for the whole range of

in-use fuels and that any testing conducted by EPA would use test fuels

typical of in-use fuels. Unfortunately, the test procedure currently

limits the Agency from reaching this objective for marine diesel

engines if in-use fuels do in fact have sulfur levels as high as the

current ASTM specifications allow. EPA requests comment on whether

currently available marine fuel has a sulfur content significantly

higher than land-based nonroad fuel. EPA will be investigating marine

fuel further and is requesting information on the specifications that

are used in use. It is EPA's intent to develop test procedures that

will allow for the accurate measurement of PM emission over the entire

range of in-use fuel characteristics. If successful, the Agency would

intend to broaden the range of certification fuel to reflect the full

range of in-use fuels. Any efforts to do so would consider the impacts

on the appropriateness and feasibility of the PM standards and would

likely be undertaken in the planned 2003 technology review for the Tier

3 standards.

EPA requests comment on all aspects of its proposed test fuel

provisions. EPA is also interested in obtaining more information on the

specifications of marine fuel used in Category 2 marine engines.

Essentially, this proposal assumes that Category 2 marine engines are

operating on a distillate fuel. The Agency requests comments on this

approach and on how often residual fuels or residual fuel blends are

burned in Category 2 engines.

4. Adjustable Parameters

Marine diesel engines are often designed with adjustable

components, to allow the engine to be adjusted for maximum efficiency

when used in a particular application. This practice simplifies marine

diesel engine production, since the same basic engine can be used in

many applications. While EPA recognizes the need for this practice, EPA

is also concerned that the engine meet the proposed emission limits

throughout the range of adjustment. Therefore, and consistent with the

locomotive rule, the Agency is proposing that manufacturers specify in

their applications for certification the range of adjustment for these

components across which the engine is certified to comply with the

applicable emission standards, and demonstrate compliance across that

range.

Practically, this requirement means that a manufacturer would

specify a range of fuel injection timing, for example, over which the

engine would comply with the emission standards. This range could be

designed to account for differences in fuel quality. Operators would

then be prohibited by the anti-tampering provisions from adjusting

engines outside of this range.

Ideally, to ensure that engines are always operated within the

specified range of adjustment, marine diesel engine manufacturers

should be required to design their engines to prevent adjustments

outside the specified range. However, EPA recognizes that it may be

necessary to adjust injection timing or other adjustable parameters

outside the originally specified control range during engine

remanufacture to accommodate engine wear. There are at least two

alternative solutions to this problem. First, engine manufacturers

could be

[[Page 68528]]

required to set a range of adjustments that would accommodate changes

necessary at the time the engine will be remanufactured. Alternatively,

compliance with the range of adjustments could be ensured through anti-

tampering provisions, with the requirement that the new range of

adjustments be specified at the time of remanufacture. EPA seeks

comments on these and other approaches to ensure that engines with

adjustable parameters meet the proposed emission requirements.

5. Definition of Rated Speed

The definition of rated speed, where speed is the angular velocity

of an engine's crankshaft (usually expressed in revolutions per minute,

or rpm) is an important aspect of the test cycles and ``not-to-exceed''

(NTE) zones proposed in this document. In the past, EPA has expected

engine manufacturers to declare reasonable rated speeds for their

engines; however, EPA is concerned that some manufacturers may have

declared rated speeds that are not really representative of the

operating characteristics of a particular engine in order to influence

the parameters under which their engines could be certified. Under

EPA's highway transient duty cycle, manufacturers would likely receive

a NOX emission benefit if they declared a rated speed that

was higher than the actual rated speed of the engine. Under EPA's

nonroad and proposed marine steady-state duty cycles, manufacturers

would likely receive a NOX emission benefit if they declared

a lower rated speed. In addition, a low declared rated speed would

shrink a marine engine's NTE zone.

Currently, U.S. highway and nonroad diesel engine regulations

specify two slightly different ways to determine rated speed. EPA's

highway heavy-duty diesel regulation defines rated speed as the

manufacturer's specified rated speed, as defined at 40 CFR 86.082-2, or

calculated speed, whichever yields the higher speed. The calculated

speed in the highway rule is determined by averaging the minimum and

maximum speeds at which 98% of maximum power is generated. This

calculation can yield unreasonable speeds in some high-torque-rise

engines. EPA's nonroad rule defines rated speed as the maximum full-

load governed speed for governed engines and the speed of maximum

horsepower for ungoverned engines. The International Standards

Organization (ISO-8178) defines a diesel engine's rated speed as the

speed at which, according to the statement of the engine manufacturer,

rated power is delivered. This is similar to the International Maritime

Organization's definition; the crankshaft revolutions per minute at

which the rated power occurs as specified on the nameplate and in the

Technical File of the marine diesel engine.

To determine a single rated speed definition that encompasses the

complete range of engine operation, EPA analyzed the maximum-power

versus speed curves from eleven highway and nonroad engines. These

engines were all similar to marine engines and they may be used in

marine applications. EPA observed that most mechanically governed

engines had distinct governor droops at speeds slightly higher than the

speed at maximum power. High-torque-rise engines, however, had gradual

decreases in power beyond the maximum-power speed, followed by a steep

rate of governor droop. Furthermore, some electronically governed

engines had multiple rates of power decrease between the maximum-power

speed and the onset of governor droop. See Figure 1 for an illustration

of four different maximum-power versus speed curves.

Based on this analysis, EPA proposes that the rated speed of any

engine shall be defined at the single point on an engine's maximum-

power versus speed curve that lies farthest away from the zero-power,

zero-speed point on a normalized maximum-power versus speed plot. In

other words, consider straight lines drawn between the origin (speed =

0, load = 0) and each point on an engine's maximum-power versus speed

curve (see Figure 1). Note that the maximum-power versus speed curve is

normalized so that 100% power and 100% speed are set at the maximum

power and maximum-power speed point. Under this proposal, rated speed

would be defined at that point where the magnitude (length) of this

line reaches its maximum value. The magnitude of this line, called

Rated__Speedfactor in this rule, is calculated by using the

following equation:

[GRAPHIC] [TIFF OMITTED] TP11DE98.000

Rated speed shall be the speed value of the data point that returns

the maximum value of Rated__Speedfactor.

EPA proposes the following procedure to determine rated speed:

1. Generate maximum-power versus speed data points by using the

appropriate method defined in 40 CFR 86.1332-90. EPA recognizes that 40

CFR 86.1332-90 does not address the issue of electronic engines that

vary injection timing, rate shaping, exhaust gas recirculation, and

variable-nozzle turbocharging with respect to their operating

conditions. These engines' maximum-power versus speed curves can vary

as a function of the method in which the curves are determined (i.e.,

transient curve generation versus steady-state curve generation). EPA

proposes that the engine operation generating the maximum

Rated__Speedfactor shall be the operation under which rated

speed is determined. EPA seeks comment on this proposal.

2. Compare power values to determine the point where power is a

maximum.

3. Normalize power values with respect to maximum power.

4. Normalize speed with respect to the speed at which maximum power

is generated.

5. Calculate the Rated__Speedfactor for each normalized

data point.

6. Compare all Rated__Speedfactor values to determine

the maximum value of Rated--Speedfactor.

7. The speed at which maximum Rated__Speedfactor occurs

shall be the rated speed for certification and NTE zone testing.

Examples of results from this calculation are illustrated by

circles superimposed on four maximum-power versus speed curves in

Figure 1. EPA seeks comment on this proposal.

[[Page 68529]]

[GRAPHIC] [TIFF OMITTED] TP11DE98.001

F. Not-to-Exceed Requirements

EPA's goal is to achieve control of emissions over the broad range

of in-use speed and load combinations that can occur on a vessel so

that real-world emission control is achieved, rather than just

controlling emissions under certain laboratory conditions. An important

tool for achieving this goal is an in-use program with an objective

standard and an easily implemented test procedure. Historically, EPA's

approach has been to set a numerical standard on a specified test

procedure and rely on the prohibition of defeat devices to ensure in-

use control over a broad range of operation not included in the test

procedure.

No single test procedure can cover all real world applications,

operations, or conditions. Yet to ensure that emission standards are

providing the intended benefits in use, the Agency must have a

reasonable expectation that emissions under real world conditions

reflect those measured on the test procedure. The defeat device

prohibition is designed to ensure that emissions controls are employed

during real world operation and not just under laboratory or test

procedure conditions. However, the defeat device prohibition is not a

quantified standard and does not have an associated test procedure, so

it does not have the clear objectivity and ready enforceability of a

numerical standard and test procedure. As a result, the current focus

on a standardized test procedure makes it harder to ensure that engines

will operate with the same level of control in the real world as in the

test cell.

Because the E3 duty cycle uses only four modes on an average

propeller curve to characterize marine diesel engine operation, EPA is

concerned that an engine designed to the duty cycle would not

necessarily perform the same way over the range of speed and load

combinations seen on a vessel. The E3 duty cycle is based on an average

propeller curve, but a propulsion marine engine may never be fitted

with an ``average propeller.'' For instance, a light vessel with a

planing hull may operate at lower torques than average while the same

engine operated on a heavy vessel with a deep displacement hull may

operate at higher torques than average. This can largely be a function

of how well the propeller is matched to the engine and vessel. A

planing hull vessel can operate at high torques at low speed prior to

planning. In addition, the E3 duty cycle only includes steady-state

operation while some transience is seen in use.

To ensure that propulsion emissions are controlled from marine

diesel engines over the full range of speed and load combinations seen

on vessels, EPA proposes to establish a zone under the engine's power

curve where the engine may not exceed a specified emissions limit, for

any of the regulated pollutants, under any operation that could

reasonably be expected to be seen in the real world. In addition, EPA

proposes that the whole range of real ambient conditions be included in

this ``not-to-exceed'' (NTE) zone testing. The NTE zone, limit, and

ambient conditions are described below.

EPA believes that there are significant advantages to taking this

sort of approach. The test procedure is very flexible so it can

represent any and all in-use conditions (ambient and operation).

Therefore, the NTE approach takes all of the benefits of a numerical

standard and test procedure and expands it to cover a broad range of

conditions. Also, laboratory testing makes it harder to perform in-use

testing since either the engines would have to be removed from the

vessel or care would have to be taken that laboratory-type conditions

can be achieved on the vessel. With the NTE approach, in-use testing

and compliance become much easier since emissions may be sampled during

normal vessel use. Because this approach is objective, it makes

enforcement easier and provides more certainty to the industry of what

is expected in use versus over a fixed laboratory test procedure.

Even with the NTE requirements, EPA believes that it is still

important to retain standards based on the steady-state duty cycles.

This is the standard that EPA expects the certified marine diesel

engines to meet on average in use. The NTE testing is more focused on

maximum emissions for segments of operation and should not require

additional technology beyond what is used to meet the proposed

standards. EPA believes that basing the emissions standards on a

distinct cycle and using the NTE zone to ensure in-use control creates

a comprehensive program. In addition, the steady-state duty cycles

[[Page 68530]]

give a basis for calculating credits for use in the averaging, banking,

and trading program.

The proposed NTE zone for marine diesel engines that would certify

using the E3 duty cycle is illustrated in Figure 1 and is defined by

the power curve of the engine up to rated speed. This zone is based on

the range of conditions that a marine diesel propulsion engine could

typically see in use. EPA is proposing a similar approach for engines

certified using the constant-speed E2 duty cycle. In this case, the

``not-to-exceed'' zone is at the speed for which the engine is designed

to operate for loads ranging from 25 to 100 percent of maximum load at

that speed. More detail on the development of the boundaries and

conditions associated with the proposed NTE zones may be found in

Chapter 3 of the Draft RIA. EPA requests comment on the NTE zones.

[GRAPHIC] [TIFF OMITTED] TP11DE98.002

EPA proposes the limit on emissions within the NTE zones to be 1.25

times the standard (or FEL if ABT is used) for all of the regulated

pollutants (HC, NOX, CO, PM). The standard itself is

intended to represent the average emissions under steady-state

conditions. Since it is an average, some points can be higher, some

lower, and the manufacturer will design to maximize performance and

still meet the engine standard. The NTE limit is on top of this. It is

designed to make sure that no part of the engine operation and that no

application goes too far from the average level of control. Data

presented in Chapter 3 of the Draft RIA shows that the proposed limit

of 1.25 times the standard is feasible for marine diesel engines, yet

challenging because of variations in emissions at high versus low

speeds and loads for some engines. The proposed limit is consistent

with the enforcement policy currently in place for the highway heavy-

duty diesel program.37 However, the proposed marine NTE

zones are much smaller than for highway heavy-duty diesel engines due

to the smaller range of operation typically seen in use.

---------------------------------------------------------------------------

\37\ ``Heavy-duty Diesel Engines Controlled by Onboard

Computers: Guidance on Reporting and Evaluating Auxiliary Emission

Control Devices and the Defeat Device Prohibition of the Clean Air

Act,'' U.S. EPA, October 15, 1998.

---------------------------------------------------------------------------

Although transient operation would be included in the NTE testing,

only operation that would reasonably be expected to be seen in use

would be included. Therefore, engine testing may include transient

speed and load operation. Examples of this type of transience would be

bringing a vessel to plane or changing speeds. Because the majority of

marine operation is fairly steady, EPA believes that the NTE testing

should allow for short emissions spikes under transience. Engine

testing may not include transient operation that cannot be replicated

by similar engines as installed on actual vessels in use, since those

are operations that the engine is not designed for and is not expected

to see in-use. Therefore, there would be no in-use emission impact from

such operations. To ensure that a short transience does not unfairly

give high results, EPA proposes that the emissions sampling must be at

least over a 30 second time period. This 30 second sampling period

should be long enough to allow an emissions spike to be averaged out

while still retaining a short enough period to look at a specific type

of operation. EPA proposes that an acceleration associated with

bringing a vessel to plane be eligible for inclusion in any NTE type

testing regardless of whether it falls within the NTE zone shown in

Figure 1.

The NTE standards are proposed to apply under any ambient air

conditions. Within the following air temperature and humidity ranges,

no corrections will be allowed to account for the effects

[[Page 68531]]

of temperature or humidity on emissions: 13-35 deg.C for ambient air

temperature and 7.1-10.7 grams water per kilogram of dry air for

humidity. Ambient water temperature must be in the range of 5-32 deg.C

during NTE testing. In addition, the engines must comply with the

standards for the full range of test fuel specifications.

The defeat device provisions established for highway and nonroad

engines are proposed to apply to marine diesel engines in addition to

the NTE requirements. A design in which an engine met the standard at

the steady-state test points but was intentionally designed to approach

the NTE limit everywhere else would be considered to be defeating the

standard. Electronic controls that recognize when the engine is being

tested for emissions and adjust the emissions from the engine would be

another example of a defeat device, regardless of the emissions

performance of the engine.

EPA is aware that marine diesel engines may not be able to meet the

emissions limit under all conditions. Specifically, there are times

when emissions control must be compromised for startability or safety.

EPA is not proposing that engine starting be included in the NTE

testing. In addition, EPA manufacturers would have the option of

petitioning the Administrator to allow emissions to increase under

engine protection strategies such as when an engine overheats.

EPA proposes to allow manufacturers to petition to adjust the size

and shape of the NTE zone for certain engines if

This text is long and has been trimmed here. Open the source document for the complete record.