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Regulatory

Announcement

 Printed on Recycled Paper

United States

Environmental Protection

Agency

Air and Radiation EPA420-F-98-006

May 1998

Office of Mobile Sources

Advance Proposal for Emission

Standards for New Diesel Marine

Engines

The U.S. Environmental Protection Agency (EPA) is issuing an

Advance Notice of Proposed Rulemaking (ANPRM) for emissions from

new diesel marine engines at or above 37 kilowatts (50 horsepower).

Control of emissions from this currently unregulated source moves the

Agency one step further in the initiative to reduce the harmful health

effects of ozone and particulate matter from nonroad engine sources.

A National Emission Control Program

The results of a 1990 EPA study demonstrated the need for control of air

pollution in the nonroad engine and vehicle arena. EPA published this

finding in conjunction with the first rulemaking to set emission standards

for nonroad engines, which was completed in June 1994. In September

1997, the Agency issued a proposal for more stringent emission

standards for diesel engines used in most nonroad applications, including

marine engines below 37 kilowatts. EPA is now considering proposing a

national program to control emissions of oxides of nitrogen (NOx) and

particulate matter (PM) from larger diesel marine engines. The Agency is

publishing an Advance Notice of Proposed Rulemaking to encourage a

broader dialogue with the public regarding the emission standards under

consideration. These engines are used for propulsion and auxiliary power

on both commercial and recreational vessels in a variety of marine

applications.
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This ANPRM supplements an earlier proposal for these engines initiated

as part of an overall control strategy for new gasoline spark-ignition (SI)

and diesel compression-ignition (CI) marine engines. This new program

contains three sets of standards. First, for those marine diesel engines that

are derived from or use land-based nonroad or highway engine

technologies, EPA is contemplating an emission control program for

diesel marine engines similar to the Tier 2 program proposed for nonroad

land-based engines. Second, for engines that are derived from or use

locomotive technologies, EPA is contemplating numerical emission

limits similar to those applicable to land-based locomotives (finalized

December 17, 1997) or those contained in Annex VI of the International

Convention for the Prevention of Pollution from Ships (MARPOL 73/

78). Third, for low-speed, high-horsepower engines used to propel oceangoing vessels, EPA is contemplating numerical emission limits adopted

by the International Maritime

Organization (IMO). The

certification and compliance

provisions being considered

are also derived from the

program for land-based

nonroad diesel engines, but

will reflect relevant

differences in locomotive-size

and larger marine engines that

are used domestically.

Emission Reductions Expected

If the standards and other requirements are implemented as proposed, the

resulting emission reductions would translate into significant, long-term

improvements in air quality in many areas of the U.S., particularly in port

cities and coastal areas. Application of emission controls similar to the

proposed nonroad Tier 2 standards are expected to result in NOx and PM

reductions comparable to those expected from land-based engines, on a

per-engine basis. The MARPOL Annex VI emission limits were intended

to result in a 30 percent reduction of NOx emissions; actual emission

reductions will depend on the age and other characteristics of the national

fleet. Overall, the program would provide much-needed assistance to

states facing ozone and particulate air quality problems that are causing a
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range of adverse health effects for their citizens, especially in terms of

respiratory impairment and related illnesses.

Public Participation Opportunities

EPA desires full public participation in arriving at rulemaking decisions.

The Agency solicits comments from all interested parties. Wherever

applicable, full supporting data and detailed analysis should also be

submitted to allow EPA to make maximum use of the comments.

Commenters are especially encouraged to provide specific suggestions

for changes to any aspects of the proposal that they believe need to be

modified or improved.

EPA will accept comments on the ANPRM for 30 days after publication

in the Federal Register, expected in March 1998. There will also be an

opportunity for oral and written comment when EPA publishes the

Notice of Proposed Rulemaking later in the year. For instructions on

submitting written comments, please see the Federal Register notice. It

is available from the EPA Air and Radiation Docket by calling 202-260-

7548; please refer to Docket No. A-97-50. In addition, the ANPRM and

related documents are available electronically via the EPA Internet server

at:

http://www.epa.gov/OMSWWW/marine.htm

For More Information

Additional documents on marine engines are available electronically at

the Internet site given above, or by contacting:

U.S. Environmental Protection Agency

Office of Mobile Sources

2000 Traverwood

Ann Arbor, Michigan 48105