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Regulatory

Announcement

 Printed on Recycled Paper

United States

Environmental Protection

Agency

Air and Radiation EPA420-F-98-044

November 1998

Office of Mobile Sources

Proposed Emission Standards for

New CI Marine Engines

A National Emission Control Program

EPA is proposing a national program to control emissions of oxides of

nitrogen (NOx) and particulate matter (PM) from large marine diesel

engines. These engines are used for propulsion and auxiliary power on

commercial vessels in a variety of marine applications, including fishing

boats, tug and towboats, dredgers, coastal and Great Lakes cargo vessels, and ocean going vessels. Engines for recreational vessels will be

covered by a subsequent rulemaking action.

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 April

1998, the Agency issued final requirements for emission controls for

locomotive engines. In September 1998, the Agency issued final requirements for more stringent emission standards for diesel engines

used in most nonroad applications, including marine engines below 37

kilowatts.

The U.S. Environmental Protection Agency (EPA) is issuing a Notice of

Proposed Rulemaking (NPRM) for emissions from new compressionignition (CI) marine engines rated over 37 kilowatts (50 horsepower).

Control of emissions from this currently unregulated source will help

reduce the harmful health effects of ozone and particulate matter from

nonroad engine sources.
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Emissions from marine diesel engines account for about 4.5 percent of

total mobile source NOx emissions nationwide and about 1 percent of

PM emissions. However, because of the nature of their operation, the

contribution of these engines to total NOx emissions in port cities and

coastal areas is higher. This NPRM supplements these actions by proposing a comprehensive emission control program for the marine derivatives

of these land-based engines. It also follows an Advance Notice of Proposed Rulemaking (ANPRM) published in the Federal Register on May

22, 1998, that described the background and general provisions the

Agency was considering for marine diesel engine emission controls.

Highlights of Proposed Rule

This NPRM proposes three important sets of provisions. First, it sets out

a two-phase emission control strategy for marine diesel engines that are

derived from, or use the same technologies as, land-based nonroad or

locomotive engines. The first phase would go into effect in 2004 or 2006,

depending on engine size. The

second phase would go into

effect in 2008 or 2010, but will

be subject to a feasibility

review in 2003. Larger engines

would be required to meet the

emission limits finalized by

the International Maritime

Organization (IMO). The IMO

limits would also apply to the

smaller engines prior to 2004.

Second, the NPRM proposes a new approach for controlling off-cycle

emissions, and calls for engine manufacturers to demonstrate compliance

with the emission limits over a variety of operating conditions. These offcycle requirements would become effective with the 2004/2006 emission

limits. Finally, the certification and compliance provisions being considered are derived from the programs for land-based nonroad or locomotive

engines, but will reflect unique characteristics of the marine derivatives

of these engines.
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Health and Environmental Benefits

If the emission standards and other requirements are implemented as

discussed in the proposed rule, EPA would expect to see a 34 percent

reduction in NOx emissions and a 14 percent reduction in PM emissions

in 2030 when the program is fully phased-in. Overall, the program

would provide much-needed assistance to states facing ozone and

particulate air quality problems that are causing a 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 hold a pubic hearing in January 1999 and will accept written

comments on the NPRM for 60 days after publication in the Federal

Register, expected in December 1998. 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/oms/marine.htm

For More Information

Additional documents on marine engines are available electronically at

the Internet site given above, or by contacting:

CI Marine Team

U.S. Environmental Protection Agency

Office of Mobile Sources

2000 Traverwood

Ann Arbor, Michigan 48105

(734) 214-4278