ENVIRONMENTAL PR OTECTION AGENCY
40 CFR Parts 9 and 94 [EPA-HQ-OAR-2007-0121; FRL _XXXX-X ] RIN 2060-AO38
Control of Emissions from New Marine Compression-Ignition Engines at or Above 30 Liters per Cylinder
AGENCY: Environmental Protection Agency (EPA).
ACTION: Advance notice of proposed rulemaking.

_______________________________________________________________________ SUMMARY: EPA is issuing this Advance Notice of Proposed Rulemaking (ANPRM) to invite comment from all interested parties on our pl an to propose new emission standards and other related provisions for new compression-ignition marine engines with per cylinder displacement at or above 30 liters per cylinder. We refer to these engines as Category 3 marine engines. We are considering standards for achieving large re ductions in oxides of nitrogen (NOx) and particulate matter (PM) through the use of technologies such as in-cylinder controls, aftertreatment, and low sulfur fu el, starting as early as 2011.

Category 3 marine engines are important cont ributors to our natio n’s air pollution today . This
source is and these engines are projected to continue to generate generating large amounts of NOx, PM, and sulfur oxides (SOx) that contribute to nonattainmen t of the National Ambient Air Quality Standards (NAAQS) for PM 2.5 and ozone across the United States. The emissions of
PM Ozone and ozone precursors from these engines PM 2.5 are associated with serious public health problems including premature mortality, a ggravation of respiratory and cardiovascular disease, aggravation of existing asthma, acute respiratory symptoms, chronic bronchitis, and decreased lung function. In addition, emissions from Category 3 marine engines are of particular

concern , as a source of diesel exhaust , which has been classified by EPA as a likely human carcinogen. A program such as the one under c onsideration would significantly reduce the contribution of Category 3 marine engines to national inventories of NOx, PM, and SOx, as well as air toxics, and would reduce publ ic exposure to those pollutants.

DATES: Comments must be re ceived on or before [insert date, 60 90 days after publication in the Federal Register .]

ADDRESSES: Submit your comments, identified by Docket ID No. EPA-HQ-OAR-2007- 0121, by one of the following methods:

• www.regulations.gov : Follow the on-line instructions for submitting comments.

• Email: a-and-r-docket@epa.gov

• Fax: (202) 566-9744

• Mail: Environmental Protection Agency, Mail Code: 6102T, 1200 Pennsylvania Ave., NW, Washington, DC, 20460. Please include two copies.

• Hand Delivery : EPA Docket Center (Air Docket ), U.S. Environmental Protection Agency, EPA West Building, 1301 Constitution Avenue, NW, Room: 3334 Mail Code: 2822T, Washington, DC. Such deliveries are only accepted during the Docket’s normal hours of operation, and special arrangements should be made for deliveries of boxed
information.
Instructions: Direct your comments to Docket ID No. EPA-HQ-OAR-2007-0121. EPA's policy
is that all comments received will be included in the public docket without change and may be2 made available online at www.regulations.gov , including any personal information provided,
unless the comment includes information claimed to be Confidential Business Information (CBI)
or other information whose disclosure is restrict ed by statute. Do not submit information that you
consider to be CBI or othe rwise protected through www.re gulations.gov or e-mail. The www.regulations.gov website is an “anonymous access” system, which means EPA will not know your identity or contact in formation unless you provide it in the body of your comment. If you send an e-mail comment directly to EP A without going through www.regulations.gov your e-mail address will be automatically captured and in cluded as part of the comment that is placed in the public docket and made av ailable on the Internet. If yo u submit an electronic comment, EPA recommends that you include your name and other contact information in the body of your comment and with any disk or CD-ROM you subm it. If EPA cannot read your comment due to technical difficulties and cannot contact you for cl arification, EPA may not be able to consider your comment. Electronic files should avoid the use of special characters, any form of encryption, and be free of any def ects or viruses. For additional information about EPA’s public docket visit the EPA Docket Center homepage at http://www.epa.gov/epahome/dockets.htm.

Docket: All documents in the doc ket are listed in the www.regulations.gov index. Although listed in the index, some information is not pub licly available, e.g., CBI or other information whose disclosure is restricted by statute. Certain other material , such as copyrighted material, will be publicly available only in hard copy. P ublicly available docket materials are available either electronically in www.regulations.gov or in hard copy at the EPA Docket Center, EPA/DC, EPA West, Room 3334, 1301 Constituti on Avenue, NW, Washington, DC. The Public Reading Room is open from 8:30 a.m. to 4: 30 p.m., Monday through Friday, excluding legal holidays. The telephone number for the Pub lic Reading Room is (202) 566-1744, and the telephone number for the Air Docket is (202) 566-1742.

FOR FURTHER INFORMATION CONTACT: Michael Samulski, Assessment and Standards Division, Office of Transportation and Air Quality, 2000 Traverwood Drive, Ann Arbor, MI, 48105; telephone number: (734) 214-4532; fax number: (734) 214-4050; email
address: samulski.michael@epa.gov

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SUPPLEMENTARY INFORMATION:

I. General Information

A. Does this Action Apply to Me?

This action will affect companies that manufactur e, sell, or import into the United States new marine compression-ignition engi nes for use on vessels flagged or registered in the United States; companies and persons that make vessels th at will be flagged or registered in the United States and that use such engines; and the owners or operators of such U.S. vessels. Owners and operators of vessels flagged elsewhere may also be affected, to the extent they use U.S. shipyards or maintenance and repair facilities; see also Se ction VII.E regarding pote ntial application of the standards to foreign vessels that enter U.S. ports. Finally, this action may also affect companies and persons that rebuild or main tain these engines. Affected categories and entities include the following:3 Category NAICS Code a Examples of potentially affected entities Industry 333618 Manufacturers of ne w marine diesel engines. Industry 336611 Manufacturers of marine vessels. Industry 811310 Engine repair and maintenance. Industry 483 Water transportation, freight and passenger. Industry 324110 Petroleum Refineries. Industry 422710, 422720 Petroleum Bulk Stati ons and Terminals; Petroleum and
Petroleum Products Wholesalers.

a North American Industry Classification System (NAICS)

This table is not intended to be exhaustive, bu t rather provides a guide for readers regarding entities likely to be regulated by this action. To determine whethe r particular activities may be affected by this action, you should carefully exam ine the regulations. You may direct questions regarding the applicability of this action as noted in FOR FURTHER INFORMATION
CONTACT

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B. What Should I Consider as I Prepare My Comments for EPA?

1. Submitting CBI. Do not submit this information to EPA through www.regulations.gov or e-mail. Clearly mark the part or all of th e information that you claim to be CBI. For CBI information in a disk or CD ROM that you mail to EPA, mark the outside of the disk or CD ROM as CBI and then identify electronically within the disk or CD ROM the specific
information that is claimed as CBI. In additi on to one complete version of the comment that includes information claimed as CBI, a copy of the comment that does not contain the information claimed as CBI must be submitted for inclusion in the public docket. Information so marked will not be disclosed except in accordance with procedures set forth in 40 CFR Part 2.

2. Tips for Preparing Your Comments. When submitting comments, remember to:

• Identify the rulemaking by docket number and other identifying information (subject heading, Federal Regist er date and page number).

• Follow directions - The agency may ask you to respond to specific questions or organize comments by referencing a Code of Federal Regulati ons (CFR) part or
section number.

• Explain why you agree or disagree, suggest alternatives, and substitute language for your requested changes.

• Describe any assumptions and provide any technical information and/or data that you used.

• If you estimate potential costs or burd ens, explain how you arrived at your estimate in sufficient detail to allow for it to be reproduced.

• Provide specific examples to illustrate your concerns, and su ggest alternatives.

• Explain your views as clearly as possibl e, avoiding the use of profanity or personal threats.

• Make sure to submit your comments by the comment period deadline identified.

II. Additional Information About This Rulemaking4 The current emission standards for new compressi on-ignition marine engines with per cylinder displacement at or above 30 lit ers per cylinder were adopted in 2003 (see 68 FR 9746, February 28, 2003). This ANPRM relies in part on informa tion that was obtained for that rule, which can be found in Public Docket EPA-HQ-OAR-2003-0045. This docket is incorporated into the docket for this action, EPA-HQ-OAR-2007-0121.

Table of Contents
I. Overview A. Background: EPA’s Current Category 3 Standards B. Program Under Consideration II. Why is EPA Considering New Controls?
A. Ozone and PM Attainment B. Public Health Impacts
1. Particulate Matter
2. Ozone
3. Air Toxics
C. Other Environmental Effects 1. Visibility 2. Plant and Ecosystem Effects of Ozone 3. Acid Deposition 4. Eutrophication and Nitrification 5. Materials Damage and Soiling
III. Relevant Clean Air Act Provisions IV. International Regulation of Air Pollution from Ships
V. Potential Standards and Effective Dates
A. U.S. Proposal to IMO
1. NOx Standards
2 B . PM and SOx Standards
B. Other Pote ntial Standards
1. NOx Standards 2. Fuel Quality Standards VI. Emission Control Technology A. Engine-Based NOx Control 1. Traditional In-Cylinder Controls 2. Water-Based Technologies
3. Exhaust Gas Recirculation
B. NOx Aftertreatment
C. PM and SOx Control 1. In-Cylinder Controls 2. Fuel Quality
3. Exhaust Gas Scrubbers
VII. Certification and Compliance A. Testing 1. PM Sampling
2. Off

- Cycle Emissions 2. Low Power Operation
3. Test Fuel5 B. On-off Technologies C. Parameter Adjustment D. Certification of Existing Engines E. Other Compliance Issues 1. Engines on Foreign-Flagged Vessels 2. Non-Diesel Engines VIII. Potential Regulatory Impacts A. Emission Inventory 1. Estimated Inventory Contribution 2. Inventory Calcul ation Methodology
B. Potential Costs IX. Statutory and Executive Order Reviews A. Executive Order 12866: Regul atory Planning and Review B. Paperwork Reduction Act C. Regulatory Flexibility Act
D. Unfunded Mandates Reform Act
E. Executive Order 13132: Federalism
F. Executive Order 13175: Consultation and Coordination with Indian Tribal
Governments
G. Executive Order 13045: Protection of Children from Environmental Health and Safety Risks
H. Executive Order 13211: Actions that Significantly Affect Energy Supply, Distribution, or Use I. National Technology Tr ansfer Advancement Act
J. Executive Order 12898: Federal Actions to Address Environmental Justice in Minority Populations and Low-Income Populations



## I. Overview

In recent years, EPA has adopted major new programs designed to reduce emissions from diesel engines. When fully phase d in, these new programs for highway 1 and land-based
nonroad 2 diesel engines will lead to the eliminat ion of over 90 percent of harmful regulated pollutants from these sources. The public health a nd welfare benefits of these actions are very significant, projected at over $70 billion and $83 billion for ou r highway and land-based nonroad diesel programs, respectively. In contrast, th e corresponding cost of these programs will be a
small fraction of this amount. We have estimate d the annual cost at $4.2 billion and $2 billion, respectively in 2030. These pr ograms are being implemented over the next decade.

We have also recently proposed a new emission control program for locomotives and marine diesel engines. 3 The proposed standards would addre ss all types of diesel locomotives (line-haul, switch, and passenger ra il) and all types of marine di esel engines below 30 liters per cylinder displacement (including propulsion engine s used on vessels from recreational and small fishing boats to super-yachts, tugs and Great Lakes freighters, and auxi liary engines ranging

1 66 FR 5001, January 18, 2001

2 69 FR 38957, June 29, 2004

3 72 FR 15937, April 3, 20076 from small generator sets to larg e generators on ocean-going vessels). 4 The proposal consists of a three-part program. First, we are proposing mo re stringent standards for existing locomotives that would apply when they are remanufactured ; we are also requesting comment on a program that would apply a similar requirement to existi ng marine diesel engines up to 30 liters per cylinder displacement when they are remanufactur ed. Second, we are proposing a set of nearterm emission standards, referred to as Tier 3, for newly-built locomotives and marine engines up to 30 liters per cylinder displacement that reflec t the application of in-c ylinder technologies to reduce engine-out NOx and PM. Third, we are proposing longer-term standards for locomotive engines and certain marine diesel engines, referr ed to as Tier 4 standards, that reflect the application of high-efficiency ca talytic aftertreatment technology enabled by the availability of ultra-low sulfur diesel (ULSD) fuel.

Marine diesel engines above 30 liters per cylinder, called Category 3 marine diesel engines, are significant contributo rs to our national mobile sour ce emission inventory. Category 3 marine engines are predominantly used in ocean

- going vessels (OGV) . The contribution of these engines to national inventories is described in section VIII.A of this preamble. These
inventories are expected to grow significantly due to expected increases in foreign trade. Without new controls, we anticipate that their ov erall contribution to mobile source oxides of nitrogen (NOx) and fine di esel particulate matter (PM 2.5 ) emissions will increase to about 34 and 45 percent respectively by 2030. Their contribution to emissions in port areas on a percentage basis would be expected to be significantly higher.

Reducing emissions from these engines can l ead to improvements in public health and would help states and localitie s attain and maintain the PM and ozone national ambient air quality standards. Both ozone and PM 2.5 contribute to are associated with serious public health problems, including premature mort ality, aggravation of respirator y and cardiovascular disease (as indicated by increased hospital admissions and emergency room visits, school absences, loss work days, and restricted activity days), cha nges in lung function and increased respiratory symptoms, altered respiratory defense mechanisms , and chronic bronchitis. In addition, diesel exhaust is of special public he alth concern. Since 2002 EPA has classified diesel exhaust as likely to be carcinogenic to humans by i nhalation at environmental exposures. 5 Recent studies are showing that populations living near large di esel emission sources such as major roadways 6

, rail yards, and marine ports 7 are likely to experience greater di esel exhaust exposure levels than the overall U.S. population, putting them at greater health risks. We ar e currently studying the size of the US population living near a sample of approximately 50 marine ports and will place

4 Marine diesel engines at or above 30 l/cyl displacement are not includ ed in this program.

5 U.S. EPA (2002) Health Assessment Document for Diesel Engine Exhaust. EPA/600/8-90/057F. Office of Research and Development, Washington DC. This document is available electronically at http://cfpub.epa.gov/ncea/cfm/ recordisplay.cfm?deid=29060 . This document is available in Docket EPA-HQ-OAR2007-0121.

6 Kinnee,E.J.; Touman, J.S.; Mason, R.; Thurman,J.; Beidler, A.; Bailey, C.; Cook, R. ( 2004) Allocation of onroad mobile emissions to road segments for air toxics modeling in an urban area. Transport. Res. Part D 9: 139-150.

7 State of California Air Resources Board. Roseville Ra il Yard Study. Stationary Source Division, October 14, 2004. This document is available electronically at: http://www.arb.ca.gov/diesel/documents/rrstudy.htm and State
of California Air Resources Board. Diesel Particulat e Matter Exposure Assessment Study for the Ports of Los Angeles and Long Beach, April 2006. This document is available electronically at: http://www.arb.ca.gov/regact/m arine2005/portstudy0406.pdf . This document is available in Docket EPA-HQ-OAR2007-0121.7 this information in the docket for this ANPRM upon completion.

Category 3 marine engines are currently s ubject to emission sta ndards that rely on engine-based technologies to re duce emissions. These standard s, which were adopted in 2003 and went into effect in 2004, are equivalent to the NOx limits in Annex VI to the MARPOL Convention, adopted by a Confer ence of the Parties to the Co nvention in 1997. The opportunity to gain large additional public health benef its through the applicati on of advanced emission control technologies, includi ng aftertreatment, lead us to cons ider more stringent standards for these engines. In order to achieve these em ission reductions on the ship, however, it may be necessary to control the su lfur content of the fuel used in th ese engines. Finally, because of the international nature of ocean-going marine transportation, and the very large inventory contribution from foreign flagged vessels, we ma y also consider the a pplicability of federal standards to foreign vessels that en ter U.S. ports (see Section VII.E).

In this ANPRM, we describe the emission program we are considering for Category 3 marine diesel engines and technol ogies we believe can be used to achieve those standards. The remainder of this section provides background on our current emission control program and gives an overview of the program we are consider ing. Section II provides a brief discussion of the health and human impacts of emissions from Category 3 marine diesel engines. Section III
identifies relevant Clean Air Ac t provisions and Section IV summa rizes our interactions with the International Maritime Organization (IMO). In Sections V and VI, we describe the potential emission limits and the emission control technologies that can be used to meet them. Section VII discusses several compliance issues. In Secti on VIII, we summarize the contribution of these engines to current mobile source NOx and PM inve ntories in the United States and describe our plans for our future cost analysis. Finally, Se ction IX contains information on statutory and executive order reviews covering th is action. We are interested in comments covering all aspects
of this ANRPM.



### A. Background: EPA’s Cu rrent Category 3 Standards
EPA currently has emission standards for Category 3 marine diesel engines. The standards, adopted in 2003, are equivalent to the MARPOL Annex VI NOx limits. They apply to any Category 3 engine installed on a vesse l flagged or registered in the United States, beginning in 2004.

In our 2003 final rule, we considered adop ting standards that would achieve greater emission reductions through expanding the use and op timization of in-cylinder controls as well as through the use of advanced emission contro l technologies includi ng water technologies (water injection, emulsificati on, humidification) and selectiv e catalytic reduction (SCR). However, we determined that it was appropriate to defer a final decision on the longer-term Tier 2 standards to a future rulemaking. While there was a certain amount of information available at the time about the advanced technologies, there were several outstanding technical issues concerning the widespread commercial use of thos e technologies. Deferri ng the Tier 2 standards to a second rulemaking allowed us the opportunity to obtain important additional information on the use of these advanced technologies that we expected to become ava ilable over the next few years. This new information was expected to include: (1) new developments as manufacturers continue to make various improvements to th e technology and address any remaining concerns, (2) data or experience from recently initiate d in-use installations using the advanced8 technologies, and (3) information from longe r-term in-use experien ce with the advanced technologies that would be helpful for evaluating the long-term durability of emission controls. An additional reason to defer the adoption of long-term standards for Category 3 engines was to allow the United States to pursue further negotiati ons in the international arena to achieve more stringent global emission standa rds for marine diesel engines. 8

Finally, because the standards adopted in our 2003 rulemaking were equivalent to the international standards, we determined that it was appropriate to defer a decision on the application of federal standards to engines on foreign-flagged vesse ls that enter U.S. ports. We indicated that we would consider this issue ag ain in our future rulemaking, and we intend to
evaluate how best to address emissions from fo reign vessels in this action. We expect our proposal to reflect an approach similar to th e emission program recently proposed by the United
States in the current discussi ons at the IMO to amend the MARPOL Annex VI standards to a level that achieves significant reductions in NOx, PM, and SOx emissions from Category 3 marine diesel engines. 9 We will evaluate progress at the IMO and, as appropriate, consider the application of new EPA national st andards to engines on foreign-fl agged vessels that enter U.S. ports under our Clean Air Act authority.



### B. Program Under Consideration

As described in Section VI, continuing advanc ements in diesel engine control technology support the adoption of long-term technology-forcing standards for Category 3 engines. With regard to NOx control, SCR has been app lied to many land-based applications, and the technology continues to be refined and improved. More propulsion engines have been fitted with the technology, especi ally on vessels operating in the Balti c Sea, and it is being found to be very effective and durable in-use. These impr ovements, in addition to better optimization of engine-based controls, have the potential for significant NOx re ductions. PM and SOx emissions from Category 3 engines are primarily due to the sulf ur content of the fuel they use. In the short term, these emissions can be decreased by using fu el with a reduced sulfur content or through the use of exhaust gas cleaning tec hnology; this is the idea behind the SOx Emission Control Areas (SECAs) provided for in Annex VI. More sign ificant reductions can be obtained by using distillate fuel, and at least one company has been voluntarily switching from residual fuel to distillate fuel while their ships are operating within 24 nautical mile s of certain California ports. 10 Their experience demonstrates that this ty pe of fuel switching can be done safely and efficiently, although the higher price of distillate fuel may limit th is approach to near-coast and port areas. In addition, emissi on scrubbing techniques are improving, which have the potential for significant PM reductions from Category 3 engines.

We are currently considering an emission control program for new Category 3 marine diesel engines that takes advantage of these new emission reduction approaches. The program

8 68 FR 9748, February 28, 2003.

9 “Revision of the MARPOL Annex VI, the NOx Technical Code and Related Guidelines; Development of Standards for NOx, PM, and SOx,” submitted by the United States, BLG 11/5, Sub-Committee on Bulk Liquids and Gases, 11 th Session, Agenda Item 5, February 9, 2007, Docket ID EPA-HQ-OAR-2007-0121-0034. This document
is also available on our website: www.epa.gov/otaq/oceanvessels.com

10 See “Maersk Line Announces Fuel Sw itch for Vessels Calling California” at http://www.maerskline.com/globalfile/?pa th=/pdf/environment_fuel_initiative9 we are considering, described in more detail in Section V, would focus on NOx, PM, and SOx control from new and existing engines. This prog ram is similar to the one recently proposed at the IMO by the U.S. government.

For NOx control for new engines, we are cons idering a two-phase approach. In the first phase, called Tier 2, we are considering a NOx em ission limit for new engines that would be 15 to 25 percent below the current NOx limits as de fined by the NOx curve in the current Tier 1
standards. These standards woul d apply at all times. In the second phase, called Tier 3, we are considering a NOx emission limit th at would achieve an additional 80 percent reduction from the
Tier 2 limits. We are consider ing the Tier 2 limits as early as 2011 and Tier 3 limits in the 2016 time frame. Because Tier 3 standards are likely to be achieved using aftertreatment technologies, the application of the standards could be geogra phically-based thereby allo wing operators to turn the system off while they are outside of a specified geographic area. That area could be the same as the compliance area for PM and SOx reductions (see below). This two- part approach would permit near-term emission reductions while ach ieving deeper reductions through long-term
standards.

We believe a two-phase approach under cons ideration is an effective way to maximize NOx emission reductions from these engines. While we continue to believe that the focus of the emission control program should be on meaningful long-term standards that would apply highefficiency catalytic aftertreatment to these en gines, short-term emi ssion reductions could be achieved through incremental improvements to existing engine designs. These design improvements can be consistent with a long-term, afte r-treatment-based Tier 3 program. The recent experience of engine manufacturers in ap plying advanced control technologies to other mobile sources suggests that incremental changes of the type that would be used to achieve the Tier 2 standards may also be used in strategies to achieve the Tier 3 standards. For example, Tier 2 technologies may allow engine manufactur es to size their aftertre atment control systems smaller. A more stringent Tier 2 control progr am, however, may risk di verting resources away from Tier 3 and may result in the application of emission reduction st rategies that are not consistent with high-efficiency cata lytic aftertreatment -based controls.

For PM and SOx control, we are consideri ng a performance standard that would reflect
the use of low-sulfur distillate fuels or th e use of exhaust gas cleaning technology (e.g., scrubbers), or a combination of both. These standards would apply as early as 2011 and would potentially achieve SOx reductions as high as 95 percent and substantial PM reductions as well. We believe a performance stan dard would be a cost-effectiv e approach for PM emission reductions since it allows ship owners to choos e from a variety of mechanisms to achieve the standard, including fuel switching or the use of emission scrubbers. Compliance with the PM
and SOx emissions could be limite d to operation in a defined geogr aphical area. For example, ships operating in the defined coastal areas (i.e., w ithin a specified distance from shore) would be required to meet the requirements while operati ng within the area, bu t could “turn off” the control mechanism while on the open sea. This t ype of performance standa rd could apply to all vessels, new or existing, that opera te within the designated area. An important advantage of a geographic approach for PM and SOx control, as we ll as the Tier 3 standard s, is that it would result in emission reductions that are important for health and human welfare while reducing the costs of the program since ships will not be requ ired to comply with the limits while they are operating across large areas of the open sea.10 We are also considering NOx emission cont rols for existing Cate gory 3 engines that would begin in 2012. There are at least two approaches that c ould be used for setting NOx emission limits for existing engines. The firs t would be to set a performance standard, for example a reduction of about 20 percent from the Tier 1 NOx limits; how this reduction is achieved would be left up to the ship owner. Alternatively, the second approach would be to express the requirement as a specified action, for example an injector change known to achieve a particular reduction; this approach would simp lify verification, but the emission reduction results may vary across engines. We will be exploring both of these alternative approaches and seek
comment on the relative merits of each.



## II. Why is EPA Considering New Controls?

Category 3 marine engines subject to today’ s ANPRM generate significant emissions of fine particulate matter (PM 2.5 ), nitrogen oxides (NOx) and sulfur oxides (SOx) that contribute to nonattainment of the National Ambient Air Quality Standards for PM 2.5 and ozone. NOx is a key precursor to ozone and secondary PM formatio n while SOx is a significant contributor to
ambient PM 2.5 . These engines also emit volatile or ganic compounds (VOCs), carbon monoxide (CO), and hazardous air pollutants or air toxics, which are associated with adverse health effects. Diesel exhaust is of special pub lic health concern, and since 2002 EPA has classified it as likely to be carcinogenic to humans by inhalation at environmental exposures. In addition, emissions from these engines also cause harm to public welf are, contributing to visibility impairment, and other detrimental environmental impacts across the U.S.



### A. Ozone and PM Attainment
Many of our nation’s most serious ozone and PM 2.5 nonattainment areas are located along our coastlines where vessels using Category 3 marine engine emissions contribute to air pollution in or near urban areas where signifi cant numbers of people are exposed to these
emissions. The contribution of th ese engines to air pollu tion is substantial and is expected to grow in the future. Currently more than 40 major U.S. ports 11 along our Atlantic, Great Lakes, Gulf of Mexico, and Pacific co ast lines are lo cated in nonattainment ar eas for ozone and/or PM 2.5 (See Figure II-1).

The health and environmental effects asso ciated with these emissions are a classic example of a negative externality (an activity that imposes uncompensated costs on others). With a negative externality, an activity’s social cost (the cost borne by society imposed as a result of the activity taking place) exceeds its private cost (the cost to those directly engaged in the activity). In this case, emissions from Ca tegory 3 marine engines impose public health and environmental costs on society. However, these a dded costs to society are not reflected in the costs of those using these engine s and equipment. The market sy stem itself cannot correct this negative externality because firms in the market are rewarded for minimizing their operating costs, including the costs of po llution control. In addition, firms that may take steps to use equipment that reduces air pollution may find themselves at a competitive economic disadvantage compared to firms that do not. To correct The emission standards that EPA is considering for Category 3 marine di esel engines would help address this market failure and reduce the negative external ity from these emissions , it is necessary to give producers

11 American Association of Port Auth orities (AAPA), Industry Statistics, 2005 port rankings by cargo tonnage.11 responsibility for the social costs associated with emissions. Emission standards proposed by EPA will accomplish this by mandating that Category 3 marine engines reduce their emissions to providing a technologically feasible limit account ing positive incentive for social costs more fully engine manufacturers to produ ce engines that emit fewer ha rmful pollutants and for vessel builders and owners to use those cleaner engines

.

When considering vessel operations in th e United States’ Exclusive Economic Zone (EEZ), emissions from Category 3 marine engine s account for a substantia l portion of the United
States’ ambient PM 2.5 and NOx mobile source emissions. 12 We estimate that annual emissions in 2007 from these engines totaled more than 870,000 tons of NOx emissions and 66,000 tons of
PM 2.5 . This represents more than 8 percent of U.S. mobile source NOx and 15 percent of U.S.
mobile source PM 2.5 emissions. These numbers are proj ected to increase significantly through 2030 due to growth in the use of Category 3 marine engines to transport overseas goods to U.S. markets and U.S. produced goods overseas. Furt hermore, their proportion of the emission inventory is projected to increase significantly as regulat ory controls on other major emission categories take effect. By 2030, NOx emissions from these ships are projected to more than double, growing to 2.1 million tons a year or 34 pe rcent of U.S. mobile source NOx emissions
while PM 2.5 emissions are expected to almost trip le to 170,000 tons annually comprising 45 percent of U.S. mobile source PM 2.5 emissions

. . 13 In 2007 annual emission of SOx from Category 3 engines totaled almost 530,000 tons or mo re than half of mobile source SOx and by 2030 these emissions are expected to increase to 1.3 million tons or 94 percent of mobile source
emissions.

Both ozone and PM 2.5 contribute to are associated with serious public health problems, including premature mortality, aggravation of respiratory and cardi ovascular disease (as indicated by increased hospital admissions and emergency room visits, school absences, lost work days, and restricted activity days), incr eased respiratory sympto ms, altered respiratory defense mechanisms, and chronic bronchitis. Dies el exhaust is of special public health concern,
and since 2002 EPA has classified it as likel y to be carcinogenic to humans by inhalation at environmental exposures. 14

Recent studies are showing that populations li ving near large diesel emission sources such as major roadways 15 , railyards, and marine ports 16 are likely to experience greater diesel

12 In general, the United States Exclusive Economic Zone (EEZ) extends to 200 nautical miles from the U.S. coast. Exceptions include geographic regions near Canada, Mexi co and the Bahamas where the EEZ extends less than 200 nautical miles from the U.S. coast. See map in Figure VIII-1, below.

13 These projections are based on growth rates ranging from 1.7 to 5.0 percent per year, depending on the geographic region. The growth rates are described in Section VIII.A.

14 U.S. EPA (2002) Health Assessment Document for Diesel Engine Exhaust. EPA/600/8-90/057F. Office of Research and Development, Washington DC. This document is available electronically at http://cfpub.epa.gov/ncea/cfm/ recordisplay.cfm?deid=29060 . This document is available in Docket EPA-HQ-OAR2007-0121.

15 Kinnee,E.J.; Touman, J.S.; Mason, R.; Thurman,J.; Beidler, A.; Bailey, C.; Cook, R. ( 2004) Allocation of onroad mobile emissions to road segments for air toxics modeling in an urban area. Transport. Res. Part D 9: 139-150.

16 State of California Air Resources Board. Roseville Ra il Yard Study. Stationary Source Division, October 14, 2004. This document is available electronically at: http://www.arb.ca.gov/diesel/documents/rrstudy.htm and State
of California Air Resources Board. Diesel Particulat e Matter Exposure Assessment Study for the Ports of Los Angeles and Long Beach, April 2006. This document is available electronically at:12 exhaust exposure levels than the overall U.S. popul ation, putting them at greater health risks. As part of our current locomotive and marine diesel engine rulemaking (72 FR 15938, April 3, 2007), we are studying the US popula tion living near a sample of 47 marine ports which are located along the entire east and west coasts of the U.S. as well as the Gulf of Mexico and the Great Lakes region. This information will be plac ed in the docket for this rulemaking when the study is completed. The PM 2.5 and NOx reductions which would occur as a result of applying advanced emissions control strategies to Category 3 marine engines could both reduce that the
amount of emissions that the populations near these sources are exposed to and assist state and local governments as they work to reduce NOx and PM 2.5 inventories.

Today millions of Americans continue to li ve in areas that do not meet existing air quality standards. As of June 2007 there ar e approximately 88 million people living in 39 designated areas (which include a ll or part of 208 counties) that either do not meet the current
PM 2.5 NAAQS or contribute to violations in ot her counties, and 149 million people living in 94 areas (which include all or part of 391 counties) designated as not in attainment for the 8-hour ozone NAAQS. These numbers do not include th e people living in areas where there is a significant future risk of failing to maintain or achieve either the PM 2.5 or ozone NAAQS.

Figure II–1 illustrates the widespread natu re of these problems and depicts counties which are currently (as of March 2007) designate d nonattainment for either or both the 8-hour ozone NAAQS and PM 2.5 NAAQS. It also shows the location of mandatory class I federal areas for visibility. Superimposed on this map are t op U.S. ports many of which receive significant port stops from ocean going vessels operating with Category 3 marine engines. Currently more than 40 major U.S. deep sea ports are located in these nonattainment areas. Many ports are
located in areas rated as class I federal areas for visibility im pairment and regional haze. It should be noted that emissions from ocean-goi ng vessels are not simply a localized problem related only to cities that have commercial ports. Virtually all U. S. coastal areas are affected by emissions from ships that transit between those por ts, using shipping lanes th at are close to land. Many of these coastal areas also have high popula tion densities. For example, Santa Barbara, which has no commercial port, estimates that engines on ocean-going mari ne vessels currently contribute about 37 percent of total NOx in their area. 17 These emissions are from ships that transit the area, and “are compar able to (even slightly larger than) the amount of NOx produced onshore by cars and truck.” By 2015 these emissi ons are expected to increase 67 percent, contributing 61 percent of Santa Barbara’s total NOx emissions. This mix of emission sources led Santa Barbara to point out that they will be unable to meet air quality standards for ozone without significant emission reductio ns from these vessels, even if they completely eliminate all other sources of pollution. Interport emissions fr om OGV also contribute to other environmental problems, affecting sensitiv e marine and land ecosystems. As discussed above, EPA recently completed estimates of the contribution of Cate gory 3 engines to emission inventories. We recognize that air quality effects may vary from one port/coasta l area to another with differences in meteorology, because of spatial differences in emissions with ship movements within regional areas. In addition, these emissions may also aff ect adjacent coastal areas. For these reasons, we

http://www.arb.ca.gov/regact/m arine2005/portstudy0406.pdf . These documents are ava ilable in Docket EPA-HQOAR-2007-0121.

17 Memorandum to Docket A–2001–11 from Jean-Marie Re velt, Santa Barbara County Air Quality News, Issue 62, July-August 2001 and other materials provided to EPA by Santa Barbara County,’’ March 14, 2002.13 plan to study several different port areas to better assess the air quality effects of emissions from Category 3 engines. We believe that there are additional port and adjacent coastal areas affected by emissions from Category 3 marine engines. We will be performing air quality modeling specific to this issue to better assess these impacts.14 Figure II-1 Air Quality Problems are Wide spread Especially in U.S. Port Areas15 Emissions from Category 3 marine engines account for a substant ial and growing portion
of the U.S.’s coastal ambient PM 2.5 and NOx levels. The emission reductions from tightened Category 3 marine engine standards could play an important part in states efforts to attain and maintain the NAAQS in the coming decades, esp ecially in coastal nonattainment areas, where these engines comprise a large po rtion of the remaining NOx and PM 2.5 emissions inventories. For example, 2001 emission inventories for California’s South Coast ozone and PM
nonattainment areas 18 indicate that ocean-going vessels ( OGVs) contribute about 30 tons per day (tpd) of NOx and 21⁄2 tpd of PM 2.5 to regional inventories -- and absent additional emission controls, this number would almost triple in 2020 to 86 tpd of NOx and 8 tpd of PM 2.5 as port related activities continue to gr ow. The Houston-Galveston-Beau mont area is also faced with growing OGV inventories which continue to hamper their area’s effort to achieve and maintain clean air. Today, OGVs in the Houston nonattai nment area annually contribute about 27 tpd of NOx emissions and this is projected to climb to 30 tpd by 2009. 19 In the Corpus Christi area, OGVs in 2001 were responsible for about 16 tpd of NOx. 20 Finally, in the New York/Northern New Jersey nonattainment area, 2000 inventories 21 indicated that OGVs c ontributed 12 tpd of NOx emissions and about 0.75 tpd of PM 2.5 emissions to PM inventor ies. We request comment on the impact Category 3 marine engines have on state and local emission inventories as well as
their efforts to meet the ozone and PM 2.5 NAAQS.

Recently, new studies 22 from the State of Califor nia provide evidence that PM 2.5 emissions within marine ports contribute signific antly to elevated ambient concentrations near these sources. A substantial number of people ex perience exposure to Category 3 marine engine emissions, raising potential health concerns. Additional information on marine port emissions and ambient exposures can be found in section II.B.3 of this ANPRM.

18 California Air Resources Board (2006). Emission Reduction Plan for Ports and Goods Movements, (April 2006) Appendix B-3, Available electronically at www.arb.ca.gov/gmp/docs/finalgmpplan090905.pdf ; 19 Texas Commission On Environmental Quality (2006 ) Houston-Galveston-Brazoria 8-Hour Ozone State Implmental Plan & Rules, Informational Meeting Presentation, Kelly Keel, Air Quality Planning Section.

20 Air consulting and Engineering Solutions, Final Report PhassII Corpus Christi Regional Airshed, (August 2001) Project Number 21-01-0006.

21 The Port Authority of New York & New Jersey, (2003), The New York, Northern New Jersey, Long Island
Nonattainment Area Commercial Marine Vessel Emissions Inventory, Prepared by Starcrest Consulting Group,
LLC.

22 State of California Air Resources Board. Roseville Ra il Yard Study. Stationary Source Division, October 14, 2004. This document is available electronically at: http://www.arb.ca.gov/diesel/documents/rrstudy.htm and State of California Air Resources Board and State of California Air Resources Board. Diesel Particulate Matter Exposure Assessment Study for the Ports of Los Angeles and Long Beach, April 2006. This document is available electronically at: ftp://ftp.arb.ca.gov/carbis/msprog/offro ad/marinevess/documents/portstudy0406.pdf . These
documents are available in Do cket EPA-HQ-OAR-2007-0121.16 In addition to public health impacts, there are serious public welf are and environmental impacts associated with ozone and PM 2.5 . Specifically, ozone causes damage to vegetation which leads to crop and forestry economic losses, as well as harm to national parks, wilderness areas, and other natural systems. NOx, SOx and PM 2.5 can contribute to the substantial impairment of visibility in many parts of th e U.S., where people live, work, and recreate, including national parks, wilderness areas, and mandatory cl ass I federal areas. The deposition of airborne particles can also reduce the aesthetic appeal of bu ildings and culturally important articles through soiling, and can contribute directly (or in conjunction with other pollutants) to structural damage by means of corrosion or er osion. Finally, NOx and SOx emissions from diesel engines contribute to th e acidification, nitrification, and eutrophication of water bodies.

While EPA has already adopted many emission control programs that are expected to
reduce ambient ozone and PM 2.5 levels, including the Clean Air In terstate Rule (CAIR) (70 FR 25162, May 12, 2005), the Clean Air Nonroad Dies el Rule (69 FR 38957, June 29, 2004), the Heavy Duty Engine and Vehicle Standards and Highway Diesel Fuel Sulfur Control Requirements (66 FR 5002, Jan. 18, 2001), and the Ti er 2 Vehicle and Gasoline Sulfur Program (65 FR 6698, Feb. 10, 2000), the PM 2.5 and NOx emission reductions resulting from tightened standards for Category 3 marine diesel engines would greatly assist nonattainment areas, especially along our nation’s co asts, in attaining and main taining the ozone and the PM 2.5 NAAQS in the near term and in the decades to come.

In September 2006, EPA finalized revised PM 2.5 NAAQS. Nonattainment areas will be designated with respect to the revised PM 2.5 NAAQS in early 2010. EPA modeling, conducted as part of finalizing the revised NAAQS, projects that in 2015 up to 52 counties with 53 million people may violate the daily, a nnual, or both standards for PM 2.5 while an additional 27 million people in 54 counties may live in areas that have air quality measurements within 10 percent of the revised NAAQS. Even in 2020 up to 48 countie s, with 54 million people, may still not be
able to meet the revised PM 2.5 NAAQS and an additional 25 million people, living in 50 counties, are projected to have air quality measurements with in 10 percent of the revised
standards. The PM 2.5 inventory reductions that would be achieved from applying advanced emissions control strategies to Category 3 e ngines could be useful in helping coastal nonattainment areas, to both attain and maintain the revised PM 2.5 NAAQS.

State and local governments are working to prot ect the health of thei r citizens and comply with requirements of the Clean Air Act (CAA or A the Act @ ). As part of this effort they recognize the need to secure add itional major reductions in both PM 2.5 and NOx emissions by undertaking state level action. 23 However, they also seek further Agency action for national standards, including the setting of stringent new Category 3 marine engine standards since states are preempted from setting new engine emissi ons standards for this class of engines. 24

23 For example, see: California Air Resources Board ( 2006). Emission Reduction Plan for Ports and Goods Movements, (April 2006), Available electronically at www.arb.ca.gov/gmp/docs/finalgmpplan090905.pdf

24 For example, see letter dated November 29, 2006 from California Environmental Prot ection Agency to Ad ministrator Stephen L. Johnson and January 20, 2006 letter from Executive Director, Puget Sound Clean Air Agency to Administrator Stephen L.
Johnson.17 

### B. Public Health Impacts

1. Particulate Matter The emission control program for Category 3 marine engines has the potential to significantly reduce thei r contribution to PM 2.5 inventories. In addition, these engines emit high
levels of NOx which react in the atmosphere to form secondary PM 2.5, ammonium nitrate. Category 3 marine engines also emit large amounts of SO 2 and HC which react in the atmosphere to form secondary PM 2.5 composed of sulfates and organic carbonaceous PM 2.5 . The emission control program being considered woul d reduce the contribution of Category 3 engines to both directly emitted diesel PM and secondary PM emissions.

(a) Background

Particulate matter (PM) repr esents a broad class of chem ically and physically diverse substances. It can be principally characterized as discrete partic les that exist in the condensed (liquid or solid) phase spanning se veral orders of magnitude in size. PM is further described by breaking it down into size fractions. PM 10 refers to particles generally less than or equal to 10 micrometers (μm). PM 2.5 refers to fine particles, those part icles generally less than or equal to 2.5 μm in diameter. Inhalable (or “thoracic”) coarse pa rticles refer to thos e particles generally greater than 2.5 μm but less than or equal to 10 μm in diameter. Ultrafine PM refers to particles less than 100 nanometers (0.1 μm). Larger pa rticles tend to be removed by the respiratory clearance mechanisms (e.g. coughing), whereas sm aller particles are deposited deeper in the lungs.

Fine particles are produce d primarily by combustion processes and by transformations of gaseous emissions (e.g., SOx, NOx and VOCs) in the atmosphere. The chemical and physical properties of PM 2.5 may vary greatly with time, region, meteorology, and source category. Thus,
PM 2.5 , may include a complex mixture of different po llutants including sulfates, nitrates, organic compounds, elemental carbon and metal compounds . These particles can remain in the atmosphere for days to weeks and travel th rough the atmosphere hundr eds to thousands of
kilometers.

The primary PM 2.5 NAAQS includes a short-term ( 24-hour) and a long-term (annual)
standard. The 1997 PM 2.5 NAAQS established by EPA set the 24-hour standard at a level of 65μg/m 3 based on the 98th percentile concentration averaged over three years. (This air quality statistic compared to the standard is referred to as the "design value.") The annual standard specifies an expected annual arith metic mean not to exceed 15μg/m 3 averaged over three years. EPA has recently finalized PM 2.5 nonattainment designations for the 1997 standard (70 FR 943, Jan 5, 2005). 25 All areas currently in nonattainment for PM 2.5 will be required to meet these
1997 standards between 2009 and 2014.

EPA has recently amended the NAAQS for PM 2.5 (71 FR 61144, October 17, 2006). The final rule, signed on September 21, 2006 and publis hed in the Federal Register on October 17, 2006, addressed revisions to the primary and se condary NAAQS for PM to provide increased

25 US EPA, Air Quality Designations and Cl assifications for the Fine Particles (PM 2.5 ) National Ambient Air QualityStandards, December 17, 2004. (70 FR 943, Jan 5. 2005) This document is available in Docket EPA-HQ-OAR2007-0121. This document is also available on the web at: http://www.epa.gov/pmdesignations/18 protection of public health and welfare, respectively. The level of the 24-hour PM 2.5 NAAQS
was revised from 65 μ g/m 3 to 35 μ g/m 3 to provide increased protec tion against health effects associated with short-term exposures to fine particles. The current form of the 24-hour PM 2.5 standard was retained (e.g., base d on the 98th percentile conc entration averaged over three years). The level of the annual PM 2.5 NAAQS was retained at 15 μ g/m 3 , continuing protection against health effects associated with long-term exposures. The current form of the annual PM 2.5 standard was retained as an annual arithmetic mean averaged over thr ee years, however, the following two aspects of the spatial averaging criteria were narrowed: (1) the annual mean concentration at each site shall be within 10 pe rcent of the spatially averaged annual mean, and (2) the daily values for each monitoring site pair shall yield a correlation coefficient of at least 0.9 for each calendar quarter.

With regard to the secondary PM 2.5 standards, EPA has revised these standards to be identical in all respects to the revised primar y standards. Specifically, EPA has revised the
current 24-hour PM 2.5 secondary standard by making it id entical to the revised 24-hour PM 2.5 primary standard and retained the annual PM 2.5 secondary standard. Th is suite of secondary
PM 2.5 standards is intended to pr ovide protection against PM-rel ated public welfare effects, including visibility impairment, effects on vege tation and ecosystems, and material damage and soiling.

The 2006 standards became effective on December 18, 2006. As a result of the 2006
PM 2.5 standard, EPA will designate new nonattainme nt areas in early 2010. The timeframe for areas attaining the 2006 PM NAAQS w ill likely extend from 2015 to 2020.

(b) Health Effects of PM 2.5 Scientific studies show ambient PM is associated with a series of adverse health effects.
These health effects are discussed in detail in the 2004 EPA Particul ate Matter Air Quality Criteria Document (PM AQCD), and the 2005 PM Staff Paper. 26,27,28

Health effects associated with short-term exposures (hours to days) to ambient PM include premature mortality, incr eased hospital admissions, heart and lung diseases, increased cough, adverse lower-respiratory symptoms, decrem ents in lung function and changes in heart rate rhythm and other cardiac e ffects. Studies examining populati ons exposed to different levels of air pollution over a number of years, includ ing the Harvard Six Citie s Study and the American Cancer Society Study, show associations be tween long-term exposure to ambient PM 2.5 and both
total and cardiovascular and respiratory mortality. 29 In addition, a reanal ysis of the American Cancer Society Study shows an association between fine particle and sulf ate concentrations and

26 U.S.EPA (1996) Air Quality Criteria for Particulate Matte r, EPA 600-P-95-001aF, EPA 600-P-95-001bF. This document is available in Docket EPA-HQ-OAR-2007-0121.

27 U.S. EPA (2004) Air Quality Criteria for Particulate Ma tter (Oct 2004), Volume I Document No. EPA600/P99/002aF and Volume II Document No. EPA600/P-99/002bF. This document is available in Docket EPA-HQOAR-2007-0121.

28 U.S. EPA (2005) Review of the National Ambient Air Qua lity Standard for Particulate Matter: Policy Assessment of Scientific and Technical Information, OAQPS Staff Paper. EPA-452/R-05-005. This document is available in Docket EPA-HQ-OAR-2007-0121.

29 Dockery, DW; Pope, CA III: Xu, X; et al. 1993. An as sociation between air pollution and mortality in six U.S. cities. N Engl J Med 329:1753-1759.19 lung cancer mortality. 30 The Category 3 marine engines cove red in this proposal contribute to
both acute and chronic PM 2.5 exposures.

The health effects of PM 2.5 have been further documented in local impact studies which
have focused on health effects due to PM 2.5 exposures measured on or near roadways. 31 Taking account of all air pollution sources , including both spark-ignition (g asoline) and diesel powered vehicles, these latter studies indicate that exposure to PM 2.5 emissions near roadways, dominated by mobile sources, are associated with potentially serious health e ffects. For instance, a recent study found associations between co ncentrations of cardiac risk f actors in the blood of healthy young police officers and PM 2.5 concentrations measured in vehicles. 32 Also, a number of
studies have shown associations between residen tial or school outdoor c oncentrations of some constituents of fine particles found in motor ve hicle exhaust and advers e respiratory outcomes, including asthma prevalence in children who live near major roadways. 33,34,35 Although the engines considered in this proposal differ with those in these studies with respect to their applications and fuel qualities, th ese studies provide an indication of the types of health effects that might be expected to be associated with personal exposure to PM 2.5 emissions from Category 3 marine engines. By reducing their contribution to PM 2.5 inventories, the emissions
controls under consideration al so would reduce exposure to th ese emissions, specifically exposure near marine ports and shipping routes.

2. Ozone The emissions reduction program under cons ideration for Category 3 marine engines would reduce the contribution of these engines NO x inventories. These engines currently have high NOx emissions due to the size of the engine a nd because they are relatively uncontrolled. NOx contributes to the formation of ground-le vel ozone pollution or smog. People in many areas across the U.S. continue to be expos ed to unhealthy levels of ambient ozone.

(a) Background Ground-level ozone pollution is formed by the reaction of VOCs and NOx in the atmosphere in the presence of heat and sunlight. These two pollutants, often referred to as ozone precursors, are emitted by many types of pollution sources, such as highway and nonroad motor vehicles and engines, power plants, chemical plants, refineries, makers of consumer and commercial products, industrial faciliti es, and smaller “area” sources.

30 Pope Ca, III; Thun, MJ; Namboodiri, MM; Docery, DW; Evans, JS; Speizer, FE; Heath, CW. 1995. Particulate air pollution as a predictor of mortality in a prospective study of U.S. adults. Am J Respir Crit Care Med 151:669-674.

31 Riekider, M.; Cascio, W.E.; Griggs, T. R.; Herbst, M.C.; Bromberg, P.A.; N eas, L.; Williams, R.W.; Devlin, R.B. (2003) Particulate Matter Exposures in Cars is Associated with Cardiovascular Effects in Healthy Young Men. Am. J. Respir. Crit. Care Med. 169: 934-940.

32 Riediker, M.; Cascio, W.E.; Griggs, T.R.; et al. (2004) Particulate matter exposure in cars is associated with cardiovascular effects in healthy young men. Am J Respir Crit Care Med 169: 934–940.

33 Van Vliet, P.; Knape, M.; de Hartog, J.; Janssen, N.; Ha rssema, H.; Brunekreef, B. (1997). Motor vehicle exhaust and chronic respiratory symptoms in children livin g near freeways. Env. Research 74: 122-132.

34 Brunekreef, B., Janssen, N.A.H.; de Hartog, J.; Harssema, H.; Knape, M.; van Vliet, P. (1997). Air pollution from truck traffic and lung function in children livin g near roadways. Epidemiology 8:298-303.

35 Kim, J.J.; Smorodinsky, S.; Lipsett, M.; Singer, B. C.; Hodgson, A.T.; Ostro, B (2004). Traffic-related air pollution near busy roads: The East Bay children’s respirator y health study. Am. J. Respir. Crit. Care Med. 170:
520-526.20 The science of ozone formation, tran sport, and accumulation is complex. 36 Ground-level ozone is produced and destroyed in a cyclical set of chemical reactions, many of which are sensitive to temperature and sunlight. When am bient temperatures and su nlight levels remain high for several days and the air is relatively st agnant, ozone and its precursors can build up and result in more ozone than typically would occu r on a single high-temperature day. Ozone also can be transported from pollution sources into areas hundreds of miles downwind, resulting in
elevated ozone levels even in areas w ith low local VOC or NOx emissions.

The highest levels of ozone are produced when both VOC and NOx emissions are present in significant quantities on clear summer days. Relatively small amounts of NOx enable ozone to form rapidly when VOC levels are relativ ely high, but ozone production is quickly limited by
removal of the NOx. Under these conditions NO x reductions are highly effective in reducing
ozone while VOC reductions have little effect. Such conditions are called “NOx-limited”.
Because the contribution of VOC emissions from biogenic (natural) sources to local ambient ozone concentrations can be significant, even some areas where man-made VOC emissions are relatively low can be NOx limited.

When NO
x levels are relatively high and VOC leve ls relatively low, NOx forms inorganic nitrates (i.e., particles) but relatively little ozone. Such c onditions are called “VOC-limited.” Under these conditions, VOC reductions are effec tive in reducing ozone, but NOx reductions can actually increase local oz one under certain circumstances. Even in VOC-limited urban areas, NOx reductions are not expected to increase ozone levels if the NO
x reductions are sufficiently large.

Rural areas are usually NOx-limited, due to the relatively large amounts of biogenic VOC emissions in many rural areas. Ur ban areas can be either VOC- or NOx -limited, or a mixture of both, in which ozone levels exhibit moderate sensitivity to changes in either pollutant.
Ozone concentrations in an area also can be lowered by the reacti on of nitric oxide with ozone, forming nitrogen dioxide (NO 2 ); as the air moves downwind and the cycle continues, the NO 2 forms additional ozone. The importance of th is reaction depends, in part, on the relative concentrations of NOx, VOC, a nd ozone, all of which change with time and location.

The current ozone NAAQS has an 8-hour av eraging time. The 8-hour ozone NAAQS is met at an ambient air quality monitoring site when the average of the annual fourth-highest daily maximum 8-hour average ozone concentration over three years is less than or equal to 0.084 ppm. On June 20, 2007 EPA proposed to strengt hen the ozone NAAQS. The proposed revisions
reflect new scientific evidence about ozone and its effects on public health and welfare. 37 The

36 U.S. EPA Air Quality Criteria for Ozone and Related Ph otochemical Oxidants (Final). U.S. Environmental Protection Agency, Washington, D. C., EPA 600/R-05/004a F-cF, 2006. This document may be accessed electronically at: http://www.epa.gov/ttn/naaqs/standards/oz one/s_o3_cr_cd.html. This document is available in Docket EPA-HQ-OAR-2007-0121.

37 EPA proposes to set the 8-hour primary ozone standard to a level within the range of 0.070-0.075 ppm. The agency also requests comments on alternative levels of the 8-hour primary ozone standard, within a range from 0.060 ppm up to and including retention of the current standard (0.084 ppm). EPA also proposes two options for the secondary ozone standard. One option would establish a new form of standard designed specifically to protect sensitive plants from damage caused by repeated ozone e xposure throughout the growing season. This cumulative standard would add daily ozone concentrations across a three month period. EPA is proposing to set the level of the21 final ozone NAAQS rule is scheduled for March 2008.

(b) Health Effects of Ozone
The health and welfare effect s of ozone are well documented and are assessed in EPA’s 2006 ozone Air Quality Criteri a Document (ozone AQCD) and EPA staff papers. 38,39 Ozone can irritate the respiratory system, causing c oughing, throat irritation, and/or uncomfortable sensation in the chest. Ozone can reduce lung function and make it more difficult to breathe deeply, and breathing may become more rapid and shallow than normal, thereby limiting a person’s activity. Ozone can also aggravate asthma, leading to mo re asthma attacks that require
a doctor’s attention and/or the use of additi onal medication. Animal toxicological evidence indicates that with repeated exposure, ozone can inflame and damage the lining of the lungs, which may lead to permanent changes in lung tissu e and irreversible reduc tions in lung function. People who are more susceptible to effects asso ciated with exposure to ozone include children, the elderly, and individuals with respiratory disease such as asthma. As of the 2006 review, there was suggestive evidence that certain people ma y have greater genetic susceptibility. Those with greater exposures to ozone, for instan ce due to time spent out doors (e.g., children and outdoor workers), are also of concern.

The recent ozone AQCD also examined relevant new scientific information which has emerged in the past decade, in cluding the impact of ozone e xposure on such health effect indicators as changes in lung structure and biochemistry, infl ammation of the lungs, exacerbation and causation of asthma, respir atory illness-related school ab sence, hospital admissions and premature mortality. Animal toxi cological studies have suggested potential interactions between ozone and PM with increased responses observed to mixtures of the two pollutants compared to either ozone or PM alone. The respiratory morb idity observed in animal studies along with the evidence from epidemiologic studies supports a ca usal relationship betwee n acute ambient ozone exposures and increased respiratory- related emer gency room visits and hospitalizations in the warm season. In addition, there is sugges tive evidence of a cont ribution of ozone to cardiovascular-related morbidity and non-acc idental and cardiopulmonary mortality.

3. Air Toxics People experience elevated risk of can cer and other noncancer health effects from exposure to air toxics. Mobile sources are responsible for a signi ficant portion of th is exposure. According to the National Air Toxic Assessment (NATA) for 1999, mobile sources , including Category 3 marine engines, were responsible for 44 percen t of outdoor toxic emissions and almost 50 percent of the cancer risk among the 133 pollutants quantitatively assessed in the 1999 NATA. Benzene is the largest co ntributor to cancer risk of all the assessed pollutants and mobile sources were responsible for

, about 68 percent of all benzene emissions in 1999. Although the

cumulative standard within the range of 7 to 21 ppm-hours. The other option would follow the current practice of making the secondary standard equal to the proposed 8-hour primary standard.

38 U.S. EPA Air Quality Criteria for Ozone and Related Photochemical Oxidants (Fin al). U.S. EnvironmentalProtection Agency, Washington, D.C., EPA 600/R-05/004aF-cF, 2006. This document is available in Docket EPAHQ-OAR-2007-0121. This document may be accessed electronically at: http://www.epa.gov/ttn/naaqs/standards/ozone/s_o3_cr_cd.html

39 U.S. EPA (2006) Review of the National Ambient Ai r Quality Standards for Ozone, Policy Assessment of
Scientific and Technical Information. OAQPS Staff Paper Second Draft.EPA-452/D-05-002. This document is available in Docket EPA-HQ-OAR-2007-0121. Th is document is available electronically at: http:www.epa.gov/ttn/naaqs/standards/ozone/s_o3_cr_sp.html.22 1999 NATA did not quantify cancer risk s associated with exposure to diesel exhaust, EPA has
concluded that diesel exhaust ra nks with the other air toxic subs tances that the national-scale assessment suggests pose the gr eatest relative risk.

According to the 1999 NATA, nearly the entire U.S. population was exposed to an average level of air toxics that has the potential for adverse respiratory noncancer health effects (noncancer). . This potential was indicated by a hazard index (HI) greater than 1. 40 Mobile sources were responsible for 74 perc ent of the potent ial noncancer hazard 41 from outdoor air
toxics in 1999. The majority About 91 percent of this potential noncancer hazard was from
acrolein

, ; 42 however, the confidence in th e RfC for acrolein is medium 43 and formaldehyde also
contributed to the potential hazard

. Although not included confidence in NATA 's estimates of population noncancer risk, PM hazard from gasoline and diesel mobile sources contribute significantly to the ambient exposure to this pollutant is low. 44 It is important to note that
NATA estimates of noncancer haza rd do not include the adverse health effects associated with
ambient PM. particulate matter identified in EPA’s Pa rticulate Matter Air Quality Criteria Document. Gasoline and diesel engine emissions contribute significantly to with particulate
matter concentration.

It should be noted that th e NATA modeling framework has a number of limitations which prevent its use as the sole basis for setting regulatory standards. These limitations and
uncertainties are discussed on the 1999 NATA website. 45 Even so, this modeling framework is

40 To express chronic noncancer hazards, we used the RfC as part of a calculation called the hazard quotient (HQ), which is the ratio between the concentration to which a person is exposed and the RfC. (RfC is defined by EPA as, “an estimate of a continuous inhalation exposure to the human population, including sensitive subgroups, with uncertainty spanning perhaps an order of magnitude, that is likely to be without appreciable risks of deleterious noncancer effects during a lifet ime.”) A value of the HQ less than one indicates that the exposure is lower than the RfC and that no adverse health effects would be expect ed. Combined noncancer hazard s were calculated using the hazard index (HI), defined as the sum of hazard quotients fo r individual air toxic compou nds that affect the same target organ or system. As with the hazard quotient, a value of the HI at or below 1.0 will likely not result in adverse effects over a lifetime of exposure. However, a va lue of the HI greater than 1. 0 does not necessarily suggest a likelihood of adverse effects. Furthermore, the HI canno t be translated into a probability that adverse effects will occur and is not likely to be proportional to risk.

41 To expres s chronic noncancer hazards, we used the RfC as part of a cal culation called the hazard quotient (HQ), which is the ratio between the concentration to which a person is exposed and the RfC. (RfC is defined by EPA as, “an estimate of a continuous inhalation exposure to the human population, including sensitive subg roups, with uncertainty spanning perhaps an order of magnitude, that is likely to be without appreciable risks of deleterious
noncancer effects du ring a lifetime.”) A value of the HQ less than one indicates that the exposure is lower than the
RfC and that no adverse health effects would be expected.

42 U.S. EPA. U.S. EPA (2006) National-Scale Air Toxi cs Assessment for 1999. This material is available electronically at http://www.epa.gov/ttn/atw/nata1999/risksum.html.

43 U. S. EPA (2003) Integrated Risk Information System File of Acrolein. National Center for Environmental Assessment, Office of Research and Deve lopment, Washington, D.C. 2003. This material is available electronically at http://www.epa.gov/iris/subst/0364.htm.

44 U.S. EPA (2006) National-Scale Ai r Toxics Assessment for 1999. This ma terial is available electronically at http://www.epa.gov/ttn/atw/nata1999/risksum.html.

45 U. S. EPA (2006) National-Scale Air Toxics Assessment for 1999. http://www.epa.gov/ttn/atw/nata1999

.23 very useful in identifying air toxic pollutants and sources of greatest co ncern, setting regulatory priorities, and informing th e decision making process.

The following section provides a brief overview of air toxics which are associated with nonroad engines, including Category 3 marine engines, and provide s a discussion of the health
risks associated with each air toxic.

(a) Diesel Exhaust (DE) Category 3 marine engine emissions include engines emit diesel exhaust (DE), a complex mixture comprised of carbon dioxide, oxygen, nitr ogen, water vapor, carbon monoxide, nitrogen compounds, sulfur compounds and numerous low-mo lecular-weight hydrocar bons. A number of these gaseous hydrocarbon components are indivi dually known to be toxic including aldehydes, benzene and 1,3-butadiene. The diesel particul ate matter (DPM) present in diesel exhaust consists of fine particles (< 2.5μm), includi ng a subgroup with a large number of ultrafine particles (< 0.1 μm). These particles have large surface area which makes them an excellent medium for adsorbing organics and their small size makes them highly respirable and able to reach the deep lung. Many of the organic com pounds present on the partic les and in the gases are individually known to have mutagenic and car cinogenic properties. Diesel exhaust varies significantly in chemical composition and particle sizes between different engine types (heavyduty, light-duty), engine operating conditions (idle, accelerate, decelerate), and fuel formulations (high/low sulfur fuel). 46 After being emitted in the engine exhaust, diesel exhaust undergoes dilution as well as chemical and physical changes in the atmosphere. The lifetime for some of the compounds present in diesel exhaust ranges from hours to days.

(1) Diesel Exhaust: Potential Cancer Effect of Diesel Exhaust In EPA’s 2002 Diesel Health Assessment Document (Diesel HAD), 47 diesel exhaust was classified as likely to be car cinogenic to humans by inhalation at environmental exposures, in
accordance with the revised draf t 1996/1999 EPA cancer guidelines. A number of other agencies (National Institute for Occupational Safety and H ealth, the International Agency for Research on Cancer, the World Health Organi zation, California EPA, and the U. S. Department of Health and Human Services) have made similar classifications . However, EPA also concluded in the Diesel HAD that it is not possible currentl y to calculate a cancer unit risk for diesel exhaust due to a variety of factors that limit the current studies, such as limited quantitative exposure histories in occupational groups investigated for lung cancer.

For the Diesel HAD, EPA reviewed 22 epid emiologic studies on the subject of the carcinogenicity of workers exposed to diesel ex haust in various occupations, finding increased lung cancer risk, although not always statistically significant, in 8 out of 10 cohort studies and 10
out of 12 case-control studies within several industries, in cluding railroad workers. Relative risk

46 U.S. EPA (2002) Health Assessment Document for Diesel Engine Exhaust. EPA/600/8-90/057F Office of Research and Development, Washington DC. Pp1-1 1-2. This document is availa ble in Docket EPA-HQ-OAR2007-0121. This document is available electronically at http://cfpub.epa.gov/ncea/cfm/r ecordisplay.cfm?deid=29060

47 U.S. EPA (2002) Health Assessment Document for Diesel Engine Exhaust. EPA/600/8-90/057F Office of Research and Development, Washington DC. This doc ument is available in Docket EPA-HQ-OAR-2007-0121. This document is available electronically at http ://cfpub.epa.gov/ncea/cfm/reco rdisplay.cfm?deid=2906024 for lung cancer associated with exposure ranged from 1.2 to 1.5, although a few studies show relative risks as high as 2.6. Additionally, the Diesel HAD also relied on two independent metaanalyses, which examined 23 and 30 occupational studies respectively, wh ich found statistically significant increases in smoking-adju sted relative lung cance r risk associated w ith diesel exhaust, of 1.33 to 1.47. These meta-analyses demonstrate th e effect of pooling many studies and in this case show the positive relationship between di esel exhaust exposure and lung cancer across a variety of diesel exhaust-exposed occupations. 48,49,50

In the absence of a cancer unit risk, the Diesel HAD sought to provide additional insight into the significance of the diesel exhaust-ca ncer hazard by estimating possible ranges of risk that might be present in the population. An e xploratory analysis was used to characterize a possible risk range by comparing a typical environmental exposure level for highway diesel sources to a selected range of occupational e xposure levels. The occupationally observed risks were then proportionally scaled according to the exposure ratios to obtain an estimate of the possible environmental risk. A number of calcula tions are needed to accomplish this, and these
can be seen in the EPA Diesel HAD. The outcome was that environmental risks from diesel exhaust exposure could range from a low of 10 -4 to 10 -5 to as high as 10 -3 , reflecting the range of occupational exposures that coul d be associated with the rela tive and absolute risk levels observed in the occupational studies. Because of uncertainties, the analysis acknowledged that
the risks could be lower than 10 -4 or 10 -5 , and a zero risk from diesel exhaust exposure was not
ruled out.

Retrospective health studies of railroad workers have pl ayed an important part in determining that diesel exhaust is a likely human carcinogen. Key evidence of the diesel exhaust exposure linkage to lung cancer comes from two retrospective ca se-control studies of
railroad workers which are discussed at length in the Diesel HAD.

(2) Diesel Exhaust: Other Health Effects
Noncancer health effects of acute and chroni c exposure to diesel exhaust emissions are also of concern to the Agency. EPA derived an RfC from considerati on of four well-conducted
chronic rat inhalation studies s howing adverse pulmonary effects. 51,52,53,54 The RfC is 5 μg/m 3 for diesel exhaust as measured by diesel PM. Th is RfC does not consider allergenic effects such as those associated with asthma or immunologic e ffects. There is growi ng evidence, discussed in the Diesel HAD, that exposure to diesel exhaust can exacerbate th ese effects, but the exposureresponse data were found to be lacking to deri ve an RfC. The EPA Diesel HAD states, “With

48 U.S. EPA (2002) Health Assessment Document for Diesel Engine Exhaust. EPA/6008-90/057F Office of Research and Development, Washington DC. This doc ument is available in Docket EPA-HQ-OAR-2007-0121.

49 Bhatia, R., Lopipero, P., Smith, A. (1998) Diesel exposure and lung cancer. Epidemiology 9(1):84-91.

50 Lipsett, M: Campleman, S; (1999) Occupational exposure to diesel exhaust and lung cancer: a meta-analysis. Am J Public Health 80(7): 1009-1017.

51 Ishinishi, N; Kuwabara, N; Takaki, Y; et al. (1988) Long-term inhalation experiments on diesel exhaust. In: Diesel exhaust and health risks. Results of the HERP studies. Ibaraki, Japan: Research Committee for HERP Studies; pp.
11-84.

52 Heinrich, U; Fuhst, R; Rittinghausen, S; et al. (1995) Ch ronic inhalation exposure of Wi star rats and two different strains of mice to diesel engine exhaust, carbon black, and titanium dioxide. Inhal. Toxicol. 7:553-556.

53 Mauderly, JL; Jones, RK; Griffith, WC; et al. (1987) Diesel exhaust is a pulmonary carcinogen in rats exposed chronically by inhalation. Fundam. Appl. Toxicol. 9:208-221.

54 Nikula, KJ; Snipes, MB; Barr, EB; et al. (1995) Comp arative pulmonary toxicities and carcinogenicities of chronically inhaled diesel exhaust and carbon black in F344 rats. Fundam. Appl. Toxicol. 25:80-94.25 DPM [diesel particulate matter] being a ubiquito us component of ambient PM, there is an uncertainty about the adequacy of the existing DE [diesel ex haust] noncancer database to identify all of the pertinent DE-cau sed noncancer health hazards. (p. 9-19).

(3) Ambient PM 2.5 Levels and Exposure to Diesel Exhaust PM The Diesel HAD briefly summarizes health effects associated with ambient PM and discusses the EPA’s annual NAAQS of 15 μg/m 3 . In addition, both the 2004 AQCD and the 2005 Staff Paper for PM 2.5 have more recent information. There is a much more extensive body of human data showing a wide spectrum of advers e health effects associated with exposure to ambient PM, of which diesel exhaust is an important component. The PM 2.5 NAAQS is designed to provide protection from the noncan cer and premature mortality effects of PM 2.5 as a whole, of which diesel PM is a constituent.

(4) Diesel Exhaust PM Exposures Exposure of people to diesel exhaust depends on their various activitie s, the time spent in those activities, the locations where these activit ies occur, and the levels of diesel exhaust pollutants in those locations. The major differen ce between ambient levels of diesel particulate and exposure levels for diesel particulate is that exposure accounts for a person moving from location to location, proximity to the emission s ource, and whether the exposure occurs in an
enclosed environment.

Occupational Exposures Occupational exposures to diesel exhaust from mobile sources, including Category 3 marine engines, can be several orders of magn itude greater than typi cal exposures in the nonoccupationally exposed population.

Over the years, diesel particulate expo sures have been measured for a number of occupational groups resulting in a wide range of exposures from 2 to 1,280 μg/m 3 for a variety of occupations. Studies have shown that miners an d railroad workers typically have higher diesel exposure levels than other occupational groups studied, including firefighters, truck dock workers, and truck drivers (both short and long haul). 55 As discussed in the Diesel HAD, the National Institute of Occupational Safety and Health (NIOSH) has estimated a total of 1,400,000 workers are occupationally exposed to diesel exhaust from on -road and nonroad vehicles.

Elevated Concentrations and Ambient Exposures in Mobile Source-Impacted Areas Regions immediately downwind of marine ports and shipping channels experience elevated ambient concentrations of directly-emitted PM 2.5 from Category 3 marine engines. Due to the unique nature of marine ports, emissi ons from a large number of Category 3 marine engines are concentrated in a relatively small area. Furthermore, emissions occur at or near ground level, allowing emissions of diesel engines to reach nearby receptors without fully mixing with background air.

A recent study conducted by the California Air Resources Board (CARB) examined the air quality impacts of railroad ope rations at the J.R. Davis Rail Yard, the largest service and

55 Diesel HAD Page 2-110, 8-12; Woskie, SR; Smith, TJ; Hammond, SK: et al. (1988a) Estimation of the DE exposures of railroad workers: II. National and historical exposures. Am J Ind Med 12:381-394.26 maintenance rail facility in the western United States. 56 This is relevant in that locomotives use diesel engines similar to those used in marine vessels. The yard occupies 950 acres along a onequarter mile wide and four mile long section of land in Roseville, CA. The study developed an emissions inventory for the facility for the ye ar 2000 and modeled ambient concentrations of diesel PM using a well-accepted dispersion mode l (ISCST3). The study estimated substantially elevated concentrations in an area 5,000 meters from the facility, with higher concentrations closer to the rail yard. Usi ng local meteorological data, annual average contributions from the rail yard to ambient diesel PM concentrations under prevai ling wind conditions were 1.74, 1.18, 0.80, and 0.25 μg/m 3 at receptors located 200, 500, 1000, and 5000 meters from the yard, respectively. Several tens of thousands of pe ople live within the area estimated to experience substantial increases in annual average ambient PM 2.5 as a result of rail yard emissions.

Another study from CARB evaluated air quali ty impacts of diesel engine emissions within the Ports of Long Beach and Los Angeles in California, one of the largest ports in the
U.S. 57 The study found that ocean going vessels comprised 53% of the diesel PM emissions while ship auxiliary engines’ hot eling comprised another 20% of PM emissions for the marine ports. Like the earlier rail ya rd study, the port study employed the ISCST3 dispersion model. Also using local meteorological data, annual averag e concentrations were substantially elevated over an area exceeding 200,000 acres. Because th e ports are located near heavily-populated areas, the modeling indicated th at over 700,000 people lived in areas with at least 0.3 μg/m 3 of port-related diesel PM in ambient air, about 360,000 people lived in areas with at least 0.6 μg/m 3 of diesel PM, and about 50,000 people li ved in areas with at least 1.5 ug/m 3 of ambient diesel PM directly from the port. The study found that impacts could be discerned up to 15 miles from the marine port.

Overall, while these studies focus on only tw o large marine port and railroad facilities, they highlight the subs tantial contribution these faciliti es make to elevated ambient concentrations in populated areas.

We have recently initiated a study in 2006 to better understand the populations that are living near rail yards and marine ports nationally. As part of the study, this effort, a computer geographic information system (GIS) is being used to identify the locations and property
boundaries of these facilities nationally, and to determine the size and demographic characteristics of the population livi ng near these facilities . We anticipate that the results of this study will be complete completed in late 2007 and we intend to add th is report to the public
docket.

(b) Gaseous Other Air Toxics—benzene, 1,3-butadie ne, formaldehyde, acetaldehyde, acrolein, POM, naphthalene

Category 3 marine engine emissions contribut e to ambient levels of other air toxics known or suspected as human or an imal carcinogens, or that have non-cancer health effects.

56 Hand, R.; Pingkuan, D.; Servin, A.; Hunsaker, L.; Suer , C. (2004) Roseville rail yard study. California Air Resources Board. [Online at http://www .arb.ca.gov/diesel/documents/rrstudy.htm]

57 Di, P.; Servin, A.; Rosenkranz, K.; Sc hwehr, B.; Tran, H. (2006) Diesel pa rticulate matter exposure assessment study for the Ports of Los Angeles and Long Beach . California Air Resour ces Board. [Online at http://www.arb.ca.gov/msprog/offroad/marinevess/marinevess.htm]27 These other compounds include benzene, 1,3-but adiene, formaldehyde, acetaldehyde, acrolein, polycyclic organic matter (POM), and naphtha lene. All of these compounds, except acetaldehyde, were identified as national or region al risk drivers in the 1999 National-Scale Air Toxics Assessment (NATA) and have significant inventory contributions from mobile sources

. That is, for a significant portion of the population, these compounds pose a significant portion of
the total cancer and noncancer risk from breathing outdoor air toxics. Furthermore, a significant portion of total nationwide emissions of these pollutants result from mobile sources. However, EPA does not have high confidence in the NATA data for all these compounds. Reducing the emissions from Category 3 marine engines w ould help reduce exposure to these harmful
substances.

Air toxics can cause a variety of cancer a nd noncancer health effects. A number of the mobile source air toxic pollutants described in th is section are known or likely to pose a cancer hazard in humans. Many of these compounds al so cause adverse noncancer health effects resulting from chronic, 58 subchronic, 59 or acute 60 inhalation exposures. These include neurological, cardiovascular, liv er, kidney, and respiratory effect s as well as effects on the immune and reproductive systems.



### C. Other Environmental Effects
There are a number of public welfare effects associated with the presence of ozone and
PM 2.5 in the ambient air including the impact of PM 2.5 on visibility and materials and the impact of ozone on plants, including trees, ag ronomic crops and urban ornamentals.



### 1. Visibility
Visibility can be defined as th e degree to which the atmosphe re is transparent to visible light. Visibility impairment manifests in two prin cipal ways: as local visibility impairment and as regional haze. 61 Local visibility impairment may take the form of a localized plume, a band or layer of discoloration appear ing well above the terrain as a result of complex local meteorological conditions. Alternatively, local visi bility impairment may manifest as an urban haze, sometimes referred to as a “brown cloud.” This urban haze is largely caused by emissions from multiple sources in the urban areas and is not typically attributable to only one nearby source or to long-range transport. The second type of visibility impairment, regional haze, usually results from multiple pollution sources spread over a large geographic region. Regional haze can impair visibility in large regions and across states.

Visibility is important because it has direct significance to people’s enjoyment of daily activities in all parts of the country. Individuals value good visibility for the well-being it provides them directly, where they live and work, and in places where they enjoy recreational

58 Chronic exposure is defined in the glossary of the Integrated Risk Information (IRIS) database ( http://www.epa.gov/iris ) as repeated exposure by the oral, dermal, or inhalation route for more than approxima tely
10 percent of the life span in humans (more than approximatel y 90 days to 2 years in typically used laboratory animal species).

59 Defined in the IRIS database as exposure to a substance spanning approximately 10 percent of the lifetime of an organism

. 60 Defined in the IRIS database as exposure by the oral, dermal, or inhalation route for 24 hours or less.

61 See discussion in U.S. EPA , National Ambient Air Quality Standards for Particulate Matter; Proposed Rule; January 17, 2006, Vol71 p 2676. This document is available in Docket EPA-HQ-OAR-2007-0121. This information is available electronically at http://e pa.gov/fedrgstr/EPA-AIR/2006/ January/Day-17/a177.pdf28 opportunities. Visibility is also highly valued in significant natura l areas such as national parks and wilderness areas and special emphasis is given to protecting visibility in these areas. For
more information on visibili ty see the final 2004 PM AQCD 62 as well as the 2005 PM Staff Paper. 63

Fine particles are the major cause of reduced visibility in parts of the United States. EPA is pursuing a two-part strategy to address visibility. First, to a ddress the welfare effects of PM on visibility, EPA set secondary PM 2.5 standards which would act in conjunction with the establishment of a regional haze program. In setting this secondary standard EPA concluded that
PM 2.5 causes adverse effects on visi bility in various locations, depending on PM concentrations and factors such as chemical composition and av erage relative humidity. Second, section 169 of the Clean Air Act provides additional authority to address existing visibility impairment and prevent future visibility impairment in the 156 national parks, forests and wilderness areas categorized as mandatory class I fe deral areas (62 FR 38680-81, July 18, 1997). 64 In July 1999 the regional haze rule (64 FR 35714) was put in place to protect the visibility in mandatory class I federal areas. Visibility can be said to be impaired in both PM 2.5 nonattainment areas and mandatory class I federal areas.

Category 3 marine engines contri bute to visibility concerns in these areas through their primary PM 2.5 emissions and their NOx and SO 2 emissions which contribute to the formation of secondary PM 2.5

.

Recently designated PM 2.5 nonattainment areas indicate that, as of June 20, 2007, almost 90 million people live in nonattainment areas for the 1997 PM 2.5 NAAQS. Thus, at least these populations would likely be experi encing visibility impairment, as well as many thousands of
individuals who travel to these areas. In addition, while visib ility trends have improved in mandatory Class I federal areas the most recent da ta show that these areas continue to suffer from visibility impairment. In summary, visibi lity impairment is experienced throughout the U.S., in multi-state regions, urban areas, and remote mandatory class I federal areas. 65,66



### 2. Plant and Ecosystem Effects of Ozone
Ozone contributes to many environmental effect s, with impacts to plants and ecosystems being of most concern. Ozone can produce both acute and chronic injury in sensitive species depending on the concentration leve l and the duration of the exposur e. Ozone effects also tend to

62 U.S. EPA (2004) Air Quality Criteria for Particulate Matter (Oct 2004), Volume I Document No. EPA600/P99/002aF and Volume II Document No. EPA600/P-99/002bF. This document is available in Docket EPA-HQOAR-2007-0121.

63 U.S. EPA (2005) Review of the National Ambient Air Qu ality Standard for Particulate Matter: Policy Assessment of Scientific and Technical Information, OAQPS Staff Paper. EPA-452/R-05-005. This document is available in Docket EPA-HQ-OAR-2007-0121.

64 These areas are defined in section 162 of the Act as th ose national parks exceeding 6,000 acres, wilderness areas and memorial parks exceeding 5,000 acres, and all international parks which were in existence on August 7, 1977.

65 US EPA, Air Quality Designations and Cl assifications for the Fine Particles (PM 2.5 ) National Ambient Air QualityStandards, December 17, 2004. (70 FR 943, Jan 5. 2005) This document is available in Docket EPA-HQ-OAR2007-0121. This document is also available on the web at: http://www.epa.gov/pmdesignations/

66 U

. S

. EPA. Regional Haze Regulations, July 1, 1999. (64 FR 35714, July 1, 1999) This document is available in Docket EPA-HQ-OAR-2007-0121.29 accumulate over the growing season of the plant, so that even lower concentrations experienced for a longer duration have the potential to crea te chronic stress on vegetation. Ozone damage to plants includes visible injury to leaves and a reduction in food production through impaired photosynthesis, both of which can lead to redu ced crop yields, forestry production, and use of sensitive ornamentals in landscaping. In addi tion, the reduced food production in plants and subsequent reduced root growth and storage below ground, can result in other, more subtle plant and ecosystems impacts. These include increased susceptibility of plants to insect attack, disease, harsh weather, interspecies competition and overall decreased plant vigor. The adverse effects of ozone on forest and other natural vegeta tion can potentially lead to species shifts and loss from the affected ecosystems, resulting in a loss or reduction in a ssociated ecosystem goods and services. Lastly, visible ozone injury to leaves can result in a loss of aesthetic value in areas of special scenic significance like national park s and wilderness areas. The final 2006 ozone Air Quality Criteria Document (ozone AQCD) 67 presents more detailed information on ozone effects on vegetation and ecosystems.

As discussed above, Category 3 marine engine emissions of NOx contribute to ozone and
therefore the NOx standards discussed in this action would help reduce crop damage and stress on vegetation from ozone.



### 3. Acid Deposition
Acid deposition, or acid rain as it is commonly known, occurs when NOx and SO 2 react in the atmosphere with water, oxygen and oxidant s to form various acidic compounds that later fall to earth in the form of precipitation or dry deposition of acidic partic les. It contributes to damage of trees at high elevations and in extr eme cases may cause lakes and streams to become so acidic that they cannot support aquatic life. In a ddition, acid deposition accelerates the decay of building materials and paints, including irrepl aceable buildings, statues, and sculptures that are part of our nation’s cultural heritage.

The proposed NOx and SOx standards would help reduce acid deposition, thereby helping to reduce acidity levels in lakes and st reams throughout the coastal areas of our country and help accelerate the recovery of acidified lakes and streams and the revival of ecosystems adversely affected by acid deposition. Reduced acid deposition levels will also help reduce stress on forests, thereby accelerating reforestation efforts and improving timber production. Deterioration of historic buildings and monuments, vehicles, and ot her structures exposed to acid rain and dry acid deposition also will be reduced, and the cost s borne to prevent acid-related damage may also decline. While the reducti on in nitrogen acid deposition will be roughly proportional to the reduction in NOx emissions, th e precise impact of new standards would differ
across different areas.



### 4. Eutrophication and Nitrification

The NOx standards discussed in this action would help reduce the airborne nitrogen deposition that contributes to eu trophication of watersheds, partic ularly in aquatic systems where atmospheric deposition of nitrogen represents a significant portion of to tal nitrogen loadings.

67 U.S. EPA Air Quality Criteria for Ozone and Related Photoc hemical Oxidants (Final). U.S. EnvironmentalProtection Agency, Washington, D.C., EPA 600/R-05/004aF-cF,2006. This document is available in Docket EPAHQ-OAR-2007-0121. This document may be accessed electronically at: http://www.epa.gov/ttn/naaqs/standards/ozone/s_o3_cr_cd.html30 Eutrophication is the accelerated production of organic matter, pa rticularly algae, in a water body. This increased growth can cause numer ous adverse ecological effects and economic impacts, including nuisance algal blooms, diebac k of underwater plants due to reduced light penetration, and toxic plankton bl ooms. Algal and plankton blooms can also reduce the level of dissolved oxygen, which can adversely affect fish and shellfish populations. In recent decades, human activities have greatly accelerated nutri ent impacts, such as nitrogen and phosphorus, causing excessive growth of algae and leadi ng to degraded water quality and associated impairment of fresh water and estuarine resources for human uses. 68

Severe and persistent eutr ophication often directly impacts human activities. For example, losses in the nation’s fi shery resources may be directly caused by fish kills associated with low dissolved oxygen and toxic blooms. Declines in tourism occur when low dissolved oxygen causes noxious smells and floating mats of algal blooms create unfavorable aesthetic
conditions. Risks to human health increase when the toxins from algal blooms accumulate in edible fish and shellfish, and when toxins beco me airborne, causing respiratory problems due to inhalation. According to the NOAA report, more than half of the nation’s estuaries have moderate to high expressions of at least one of these symptoms – an indication that eutrophication is well developed in mo re than half of U.S. estuaries. 69



### 5. Materials Damage and Soiling
The deposition of airborne particles can re duce the aesthetic app eal of buildings and culturally important articles thr ough soiling, and can cont ribute directly (or in conjunction with other pollutants) to stru ctural damage by means of corrosion or erosion. 70 Particles affect materials principally by promoti ng and accelerating the corrosion of metals, by degrading paints, and by deteriorating building materials such as co ncrete and limestone. Particles contribute to these effects because of their electrolytic, hygrosc opic, and acidic propertie s, and their ability to adsorb corrosive gases (principal ly sulfur dioxide). The rate of metal corrosion depends on a number of factors, including the deposition rate and nature of th e pollutant; the influence of the metal protective corrosion film; the amount of moisture present; variability in the electrochemical reactions; the presence and concen tration of other surfac e electrolytes; and the
orientation of the metal surface. The PM standards discussed in this action would help reduce the airborne particles that contribute to materials damage and soiling.



## III. Relevant Clean Air Act Provisions

Section 213 of the Clean Air Act (the Act) gi ves us the authority to establish emission standards for nonroad engines and vehicles. Sec tion 213(a)(3) requires the Administrator to set (and from time to time revise) standards for NOx, VOCs, or carbon monoxide emissions from new nonroad engines, to reduce ambient levels of ozone and carbon mon oxide. That section specifies that the “standards shall achieve the gr eatest degree of emission reductions achievable

68 Deposition of Air Pollutants to the Great Waters, Third Report to Congress, June 2000, EPA-453/R-00-005. This document is available in Docket EPA-HQ-OAR- 2007-0121. It is also available at www.epa.gov/oar/oaqps/gr8water/3rdrpt/obtain.html.

69 Bricker, Suzanne B., et al, National Estuarine Eutrophica tion Assessment, Effects of Nutrient Enrichment in the Nation's Estuaries, National Ocean Service, National Oceani c and Atmospheric Administrati on, September, 1999.

70 U.S EPA (2005) Review of the National Ambient Air Quality Standards for Particulate Matter: Policy Assessment of Scientific and Technical Information, OAQPS Staff Pape r. This document is available in Docket EPA-HQ-OAR2007-0121.31 through the application of technology which the Ad ministrator determines will be available for the engines or vehicles.” As pa rt of this determination, the Admi nistrator must give appropriate consideration to lead time, noise , energy, and safety factors associ ated with the application of such technology. Section 213(a)(4 ) authorizes the Administrator to establish standards on new engines to control emissions of pollutants, such as PM, which “m ay reasonably be anticipated to endanger public health and welfare. ” In setting appropriate standards, EPA is instructed to take into account costs, noise, safety, and energy factors.

Section 211(c) of the CAA allows us to re gulate fuels where emission products of the fuel either: (1) Cause or contri bute to air pollution that reas onably may be anticipated to endanger public health or welfare, or (2) will im pair to a significant de gree the performance of any emission control device or system which is in general use, or which the Administrator finds has been developed to a point where in a reasonable time it will be in general use were such a regulation to be promulgated.



## IV. International Regulation of Air Pollution from Ships

Annex VI to the International Convention for the Prevention of Pollution from Ships (MARPOL) addresses ai r pollution from ships. Annex VI was adopted by the Parties to MARPOL at a Diplomatic Conference on Sept ember 26, 1997, and it went into force May 20, 2005. As of July 31, 2007, the Annex has been ratified by 44 countri es, representing 74.1 percent of the world’s merchant shipping tonnage. 71

Globally harmonized regulation of ship emi ssions is generally recognized to be the preferred approach for addressing air emissions from ocean-going vessels. It reduces costs for ship owners, since they would not be required to comply with a patchwork of different standards that could occur if each country was setting its own standards, and it can simplify environmental protection for port and coastal states.

The significance of international shipping to the United States can be illustrated by port entrance statistics. In 1999, according to U.S. Maritime Administration (MARAD) data, about 90 percent of annual entrances to U.S. ports we re made by foreign-fla gged vessels (75,700 total entrances; 67,500 entrances by forei gn vessels; entrances are for vesse ls engaged in foreign trade
and do not include Jones Act 72 vessels). At the same time, however, only a small portion of
those vessels account for most of the visits. In 1999, of the 7,800 forei gn vessels that visited U.S. ports, about 12 percent accounted for about 50 percent of total vessel entrances; about 30 percent accounted for about 75 percent of the vessel entrances. 73

71 See www.imo.org Go to Conventions, Status of Conventions – Summary.

72 46 USCS Appx § 688

73 Final Regulatory Support Document: Control of Emissi ons from New Marine Compression-Ignition Engines at or Above 30 Liters per Cylinder. EPA420-R-03-004, January 2003, pg. 3-50. This document is available at http://www.epa.gov/otaq/regs/nonroad/marine/ci/r03004.pdf . We will update these statistics for more recent years; however, these results are not expected to change signific antly given the U.S. share of the ownership of ocean-going vessels. MARAD data from 2005 indicates that while about 4.7 percent of all ocean-going vessels are owned by citizens of the United States (5th largest fleet) only abou t 1.9 percent of all ocean-going vessels are flagged here. Also according to that data , while Greece, Japan, China, and Germany account for the largest fleets in terms of ownership (15.3, 13.0, 11, and 8.9 percent, respectively), Panama and Liberia account for the largest fleets by flag (21.6 and 8.9 percent, respectively).32 The emission control program contained in Annex VI was the first step for the international control of air pollution from ship s. However, as early as the 1997 conference, many countries “already recognized that the NOx emission limits established in Regulation 13 were very modest when compared with current technology developments.” 74 Consequently, a Conference Resolution was adopted at the 1997 conf erence that invited the Marine Environment Protection Committee (MEPC) to review the NOx emission limits at a minimum of five-year intervals after entry into force of the protocol and, if appropriate, amend the NOx limits to reflect more stringent controls.

The United States began advocating a revi ew of the NOx emission limits in 1999. 75 However, MEPC did not formally consider the issu e until 2005, after the Annex went into effect. Negotiations for amendments to the Annex VI standards, including NOx and SOx emission limits, officially began in April 2006, with the mo st recent round of negotia tions taking place in April 2007. The United States submitted a paper to that meeting (April 2007 Bulk Liquids and Gases Sub-Committee meeting, referred to as BLG-11) setting out an approach for new international engine and fuel standards that is . That approach forms the basis of the program
outlined in this ANPRM. 76 Discussions are expected to continue through Summer 2008 and are expected to conclude at the October 2008 MEPC meeting. We w ill continue to coordinate our national rule for Category 3 emission lim its with our activities at IMO.



## V. Potential Standards and Effective Dates

A. U.S. Proposal to IMO

Over the past several years, remarkable progress has been made for land-based highway and nonroad diesel engines in reducing NOx a nd PM emissions. Current EPA standards for those land-based sources are anticipated to achiev e emission reductions of more than 90 percent
relative to uncontrolled NOx and PM levels. In contrast, Categor y 3 marine engines are subject to modest NOx standards only. As discussed above, the U.S. submitted a proposal to IMO for
new exhaust emission In this rulemaking, we are considering a comprehensive program that would set long-term standards that , if adopted, would based on the use of high-efficiency catalytic aftertreatment. These standards would achieve substantial reductions in NOx, PM, and
SOx exhaust emissions from engines on marine vessels. Here, we present the concepts in the
IMO submission that

. The program we are considering is based on the the U.S. Government proposal to IMO, which consists of near- and long-term NOx limits for new engines based on engine controls and

74 Proposal to Initiate a Revision Process, Submitted by Finland, Germany, Italy, the Netherlands, Norway, Sweden and the United Kingdom. MEPC 53/4/4, 15 April 2005. Marine Environment Protection Committee, 53 rd Session, Agenda Item 4.

75 Revision of the NOx Technical Code, Tier 2 Emission Limits for Diesel Marine Engines At or Above 130 kW, submitted by the United States. MEPC 44/11/7, 24 December 1999. Marine Environment Protection Committee,
44 th Session, Agenda Item 11.

76 “Revision of the MARPOL Annex VI, the NOx Technical Code and Related Guidelines; Development of Standards for NOx, PM, and SOx,” submitted by the United States, BLG 11/5, Sub-Committee on Bulk Liquids and Gases, 11 th Session, Agenda Item 5, February 9, 2007, Docket ID EPA-HQ-OAR-2007-0121-0034. This document
is also available on our website: www.epa.gov/otaq/oceanvessels.com33 aftertreatment technology; NOx limits for Category 3 marine certain existing engines based on engine controls; and PM/SOx limits that can be achieved through the use of exhaust gas cleaning
or low sulfur fuel. To reduce the costs of th e international program, the long-term new engine
NOx limits and the PM/SOx limits would not a pply while ships are operating on the open ocean; instead, they would in specified geogra phic areas to be defined under the treaty

. 1 This section describes in greater detail how we are considering that emission control program for our federal ac tion under the Clean Air Act.



### A . NOx Standards

Tier 2 NOx limits: We are considering new NOx emission standards for Category 3 marine diesel engines. As discussed in Sec tion VI, emission control technology for Category 3 marine engines has progressed substantially in recent years. Significant reductions can be achieved in the near term through in-cylinder cont rols with little or no impact on overall vessel performance. These technologies include traditio nal engine-out controls such as electronically controlled high pressure common-rail fuel system s, turbocharger optimization, compression-ratio changes, and electronically cont rolled exhaust valves. Furthe r emission reductions could be achieved through the use of water-b ased technologies such as wa ter emulsification, direct water injection, or intake-air humidifi cation or through exhaust gas recirc ulation. We request comment on setting a near term NOx emission standard re quiring a reduction of 15 to 25 percent below the
current Tier 1 standard. We are considering applying this near term standard to new engines as early as 2011 for new engines

.

Tier 3 NOx limits: In the longer term, we believe th at much greater emission reductions could be achieved through the us e of selective catalytic reduct ion (SCR). More than 300 SCR systems have been installed on marine vessels, some of which have been in operation for more than 10 years and have accumulated 80,000 hours of operation. While many of these applications have been limited to certain vessel classes, we believe that the technology is feasible for application to most engines given adequate lead time. As discussed in Section VI, SCR systems are capable of reducing NOx on the orde r of 90 to 95 percent compared to current emission levels. We further believe that an 80 pe rcent reduction from the Tier 2 levels discussed above is achievable throughout the life of the vessel. We are requesting comment on setting a NOx standard 80 percent below the Tier 2 standard s in the 2016 timeframe. Low sulfur distillate fuel would help in achieving these limits due to the impact of sulfur on catalyst operation; however, we do not believe low sulfur fuel is necessary to achieve these reductions. SCR systems have been used on residual fuel, with sulf ur levels as high as 2.5 to 3 percent. However low sulfur distillate fuel would allow SCR systems to be smaller, more efficient, less costly, and simpler to operate. We request comment on the need for fuel controls to enable low emission NOx technology.

NOx limits for existing engines: Due to the very long life of ocean-going vessels and the availability of known in-cylinde r technical modifications that provide significant and costeffective NOx reductions, the U.S. proposal to IMO presents potential NOx emission limits for engines on vessels built prior to the Tier 1 limits. We ar e requesting comment on requiring engines on these vessels to be retrofitted to meet the Tier 1 standard. The U.S. submittal proposed that this requirement would start in 2012. Although the Tier 1 standards went into effect in the United States in 2004, manufacturer s have been building engines with emissions
that meet this limit since 2000 due to the MA RPOL Annex VI NOx standard. Although the34 Annex VI standards did not go into force until 20 05, they apply to engines installed on vessels built on or after January 1, 2000.

Engines may be retrofitted to achieve meaningful emission reduction by applying technology used by manufacturers to meet the Tier 1 limits. These technologies include slidevalve fuel injectors and injection timing retar d. Manufacturers have in dicated that they can reduce NOx emissions by approximately 20 percen t using this technology. However, some engines have higher baseline emissions than aver age and would require mo re than a 20 percent
emission reduction to meet Tier 1 standards. Manufacturers have expresse d concerns that they would not necessarily be able to reduce emissi ons to the Tier 1 standards for such engines through a simple retrofit. Therefore, the U.S. proposal to IMO considers a standard based on percent reduction rather than an absolute numeri cal limit. Specifically, these engines would need to be modified to reduce NOx emissions by 20 per cent from their existing baseline emission rate. Alternatively, we request comment on requiring vessel operators to perform a specific action, such as a valve or injector ch ange, that would be known to achie ve a particular NOx reduction. In this case, the certification a nd compliance provisions would be based on the completion of this
action rather than achieving a specified emission reduction.

We are also considering whether standard s for existing engines should apply to all engines, regardless of age. Over time, engine manufacturer s have changed their engine platforms as new technologies have become availa ble. Many of the tech nologies that can be used to reduce NOx emissions on modern engine s may not be easily applied to older engine designs. Based on conversations with engine ma nufacturers we believe that engines built in the mid-1980s and later are compatible with the lower NOx components. Therefore we are requesting comment on excluding engines installed on a vessel prior to 1985 from this requirement. We request comment on what genera tion of engines can be retrofitted to achieve NOx reductions. Also, we request comment on the feasibility, costs, and other business impacts that would result from retrofitting existing engine s to meet a NOx standard as discussed above.



### 2 B . PM and SOx Standards

For PM and SOx emission control, we are considering emission performance standards
that would reflect the use of lo w-sulfur distillate fuels or th e use of exhaust gas cleaning technology, or a combination of both. As disc ussed in Section VI, SOx emissions and the majority of the direct PM emissions from Ca tegory 3 marine engines operated on residual fuels are a direct result of fuel quality, most notably th e sulfur in the fuel. In addition, SOx emissions form secondary PM in the atmosphere. Other components of residual fuel, such as ash and heavy metals, also contribute directly to PM. Significant PM and SO x reductions could be achieved by using low sulfur fuel re sidual fuel or distilla te fuel. Alternativel y, direct and indirect
sulfur-based PM can be reduced through the use of a s eawater scrubber in th e exhaust system. Recent demonstration projects have shown that scrubbers are capab le of reducing SOx emissions on the order of 95 percent and can achieve substantial reductions in PM as well.

We request comment on setting a PM standa rd on the order of 0.5 g/kW-hr and a SOx standard on the order of 0.4 g/kW-hr. We believe that the combination of these two performance-based standards would be a cost -effective way to approach both primary and secondary PM emission reductions because ship ow ners would have a variety of mechanisms to achieve the standard, including fuel switching or the use of emission scrubbers. This standard35 would apply as early as 2011 and would result in more than a 90 percent reduction in SOx and approximately a 50-70 percent reduction in PM. We request comment on performance based PM and SOx standards for Category 3 marine en gines, what the standards should be, and an appropriate implementation date. We also re quest comment on allowing vessel operators the option to comply with the standa rds by simply using a distillate fuel with a maximum allowable sulfur level, such as 1,000 ppm. Under th is option, no exhaust emi ssion testing would be required to demonstrate comp liance with the standard.



### B

. Other Potential Standards
A number of other emission control strategi es have been discussed at IMO and other forums. One study describes many approaches ranging fr om exhaust emission standards and operational requirements to por t fee and credit programs. 77 Below

, we discuss an intermediate
tier of NOx st andards and a fuel

- based approach to emission reductions.



### 1. NOx Standards

T he Tier 2 and Tier 3 NOx standards di scussed above consider traditional in

- cylinder technologies and advanced aftertreatment technol ogies, respectively. It may be appropriate to
consider intermediate standards base d on water technology or exhaust gas reci rculation. As
discussed in Section V I , these technologies have been demonstrated to reduce NOx by 30 to 80 percent from Category 3 marine engines . We request comment if this technology could be used to achieve a more stringent Ti er 2 NOx standard or to a chieve an intermediate standard between
the Tier 2 and 3 NOx standards discussed above . A potential emission standard based on this technology would be on the order of 50 pe rcent below the Tier 1 NOx standard.



### 2

. Fuel Quality Standards

W e are asking comm ent on whether EPA should regulate ma rine fuel quality for vessels propelled by Category 3 marine engines . For example, we could require a distillate fuel with a sulfur content at or below 1,000 ppm. The advantag e of this approach would be that there wou ld
be a substantial reduction in fuel

- bound contaminants such as sulfur , ash, and heavy metals that enter the engine. Because the contaminants wo uld not be in the fuel, they would not be e mitted to the atmosphere. In addition, fuel

- based controls would r emove the concern that fuel quality might impact in

- use degradation of exhaust cleaning devices and thus, emissions. We request comment on the feasibility and cost of supplying low sulfur distillate fuel to all ships operating in U.S. waters. We also req uest comment on negative environmen tal impacts of wastewater from
exhaust scrubbers and on the in

- use durability of exhaust aftertreatment devices used on ships.

77 Freidrich, A., Heinen, F., Kamakate, F., Kojak, D., “Air Pollution and Greenhouse Gas Emissions from Ocean

Going Ships: Impacts, Miti gation Options and Opportunities for Managing Growth,” The International Council on Clean Transportation, Ma rch 2007, Docket ID EPA

- HQ

- OAR

- 2007

- 0121

- 0033.36 

## VI. Emission Control Technology

A. Engine-Based NOx Control

1. Traditional In-Cylinder Controls
Engine manufacturers are meeting the Tier 1 NOx standards 78 for Category 3 marine engines today through traditional in-cylinder fuel and air management approaches. These incylinder emission control technol ogies include electronic controls , optimizing the turbocharger, higher compression ratio, valve timing, and optimi zed fuel injection which may include common rail systems, timing retard, increased injection pressure, rate shaping, and changes to the number and size of injector holes to increase fuel atom ization. Although U.S. standards became effective in 2004, most manufacturers began selling marine engines in 2000 that met the MARPOL Annex VI NOx standard in anticip ation of its ratification.

Manufacturers have indicated that they would be able to use in-cylinder engine control strategies to achieve further NOx emission reduc tions beyond the Tier 1 standards. EUROMOT, which is an association of engine manufactur ers, submitted a proposal to the International Maritime Organization for new Category 3 marine engine NOx standards 2 g/kW-hr below the
Tier 1 NOx standard. 79 In this submission, they pointed to the following technologies for Category 3 marine engines operating on residual fuel: fuel injection timing, high compression ratio, modified valve timing on 4-stroke engines, late exhaust valve closing on 2-stroke engines, and optimized fuel injection system and com bustion chamber. EUROMOT stated that the limiting factors for NOx design and optimization are increases in low load smoke and thermal load, PM and CO 2 emissions, fuel consumption, and concer ns about engine reliability and load acceptance. We request comment on potential emission reductions beyond the Tier 1 NOx standards that may be achieved through traditional in-cylinder technology and what the impact of the low NOx designs would be on fuel consumption, maintenance, and on PM exhaust
emissions.

Many of the same in-cylinder control technologi es used to meet the Tier 1 NOx standards can be used as retrofit technology on existing engi nes built prior to the Tier 1 standards. An example of this is retrofitting ol der fuel injectors with new inject ors using slide-valve nozzle tips. The slide-valve in the nozzle tip limits fuel “dri pping” which leads to higher HC, PM, and smoke emissions and engine fouling. This fuel no zzle can be combined with low-NOx engine calibration to achieve about a 20 percent re duction in NOx emissions through an engine
retrofit. 80 This retrofit is relatively simple on engine platforms similar to those used for the Tier 1 compliant engines, but the slide- valve injectors may not be compa tible with older engines. We request comment on whether the costs and other business impacts of retrofitting Category 3

78 This NOx standard is the same as the internationally negotiated NOx standards established by the International Maritime Organization (IMO) in Annex VI to the Intern ational Convention on the Prevention of Pollution from Ships, 1973, as Modified by the Protocol of 1978 Relating Thereto (MARPOL).

79 “MARPOL Annex VI Revision - Proposals Related to Future Emission Limits and Issues for Clarification,” Submitted by EUROMOT to the IMO Subcommittee on Bulk Liquids and Gases, BLG 10/14/12, January 26, 2006, Docket ID EPA-HQ-OAR-2007-0121-0014.

80 Henningsen, S., “2007 Panel Discussion on Emission Reduction Solutions for Marine Vessels; Engine Technologies” presentation by MAN B&W at the Clean Sh ips: Advanced Technology for Clean Air Conference, February 8, 2007, Docket ID EPA-HQ-OAR-2007-0121-0031.37 marine engines built before 2000 could be retrofitted to meet the Tier 1 NOx standard. We also request comment on what impacts there may be on costs and business practices if a retrofit program were implemented.



### 2. Water-Based Technologies
NOx emissions from Category 3 marine engine s can be reduced by in troducing water into the combustion process in combination with appropr iate in-cylinder controls . Water can be used in the combustion process to lower the maximu m combustion temperature, and therefore lower NOx formation without a significa nt increase in fuel consum ption. Water has a high heat capacity which allows it to absorb enough of the energy in the cylin der to reduce peak combustion temperatures. Data from engine manufacturers suggest that, depending on the
amount of water and how it is introduced into the combusti on chamber, a 30 to 80 percent
reduction in NOx can be achieved from Category 3 marine engines. 81,82,83 However, some increase in PM may result due to the lower combustion temperatures, depending on the water introduction strategy. 84 We request comment on the potenti al NOx reductions achievable from water-based technologies and what the impact on other pollutants or fuel consumption may be.

Water may be introduced into the combusti on process through emulsification with the fuel, direct injection into the combustion chamber, or saturating the intake air with water vapor. Water emulsification refers to mixing the fuel and water prior to injection. This strategy is limited by the instability of the water in the fuel, but can be improved by mixing the water into the fuel just prior to injection into the cylinder. More effectiv e control can be achieved through the use of an independent injecti on nozzle in the cylinder for the wate r. Using a separate injector nozzle for water allows larger amounts of water to be added to the combustion process because the water is injected simultaneously with the fuel , and larger injection pumps and nozzles can be used for the water injection. In addition, the fu el injection timing and water flow rates can be better optimized at different engine speeds and lo ads. Even higher water-to-fuel ratios can be achieved through the use of combustion air hum idification and steam injection. With combustion air humidification, a water nozzle is placed in the engine intake and an air heater is used to offset condensation. With steam injection, waste heat is used to vaporize water, which is then injected into the combustion chamber during the compression stroke.

Depending on the targeted NOx emission reduc tion, the amount of water used can range
from half as much as the fuel volume to more th an three times as much. Fresh water is necessary for the water-based NOx reduction techniques. In troducing saltwater into the engine could result
in serious deterioration due to corrosion and fouling. For this reason, a ship using water strategies would need either to produce fresh water through the use of a desalination or distillation system or to store fr esh water on-board. Often, waste he at in the exhaust is used to

81 Heim, K., “Future Emission Legislation and Reduction Possibilities,” presentation by Wartsila at the CIMAC Circle 2006, September 28, 2006, Docket ID EPA-HQ-OAR-2007-0121-0017.

82 Aabo, K., Kjemtrup, N., “Latest on Emission Control Water Emulsion and Exhaust Gas Re-Circulation,” MAN B&W, CIMAC paper number 126, presented at International Council on Combustion Engines Congress, 2004, Docket ID EPA-HQ-OAR-2007-0121-0005.

83 Hagström, U., “Humid Air Motor (HAM) and Selective Catalytic Reduction (SCR) Viking Line,” presented by Viking Line at Swedish Maritime Administration Conferen ce on Emission Abatement Technology on Ships, May 24-26, 2005, Docket ID EPA-HQ-OAR-2007-0121-0027.

84 Koehler, H., “Field Experience with Considerably Reduced NOx and Smoke Emissions,” MAN B&W, 2004, Docket ID EPA-HQ-OAR-2007-0121-0019.38 generate fresh water for on-board use. We request comment on the capabilities of marine vessels, especially ocean-going ships, to generate sufficient fresh water on-board to support the use of water-based NOx control technologies. For vessels making shorter trips, we request
comment on the practicality of costs associated with storing fresh water on board and replenishing the water supply wh en at port. We also request comment on the hardware and operating costs associated with this emission control technology.



### 3. Exhaust Gas Recirculation
Exhaust gas recirculation (EGR) is a st rategy similar to water-based NOx reduction approaches in that a non-combustible fluid (in th is case exhaust gas) is added to the combustion process. The exhaust gas is inert and reduces peak combustion temperatures, where NOx is formed, by slowing reaction rates and absorbing so me of the heat generated during combustion. One study concluded that EGR could be used to achieve similar NOx emission reductions as
water emulsion. 85 However, due to the risk of carbon de posits and deteriorati on due to sulfuric acid in the exhaust gas when high sulfur fuel is used, any exhaust gases recirculated to the cylinder intake would have to be cleaned before being routed back into the cylinder. One method of cleaning the exhaust woul d be to use a seawater scrubber. 86 Another alternative is to use internal EGR where a portion of the exhaust gases is held in the cylinder after combustion based on the cylinder scavenging design. 87 We request comment on the potential of using EG R as a NOx reduction strategy for Category 3 marine engines.



### B. NOx Aftertreatment
NOx emissions can be reduced substantially using selective catalytic reduction (SCR), which is a commonly-used techno logy reducing NOx emissions standa rds in diesel applications worldwide. Stationary power plants fueled with coal, diesel, and natura l gas have used SCR for three decades as a means of controlling NOx emissions. European heavy-duty truck manufacturers are using this technology to meet Euro 5 emissions limits and several heavy-duty truck engine manufacturers have indicated that they will use S CR technology to meet stringent U.S. NOx limits beginning in 2010. Collaborative research and development activities between diesel engine manufacturers a nd SCR catalyst suppliers suggest that SCR is a mature, costeffective solution for NOx reduction on diesel engines.

SCR has also been demonstrated for use with marine diesel engines. More than 300 SCR systems have been installed on marine vessels, some of which have been in operation for more than 10 years and have accumulated 80,000 hours of operation. 88,89,90,91 These systems are used

85 Aabo, K., Kjemtrup, N., “Latest on Emission Control Water Emulsion and Exhaust Gas Re-Circulation,” MAN B&W, CIMAC paper number 126, presented at International Council on Combustion Engines Congress, 2004, Docket ID EPA-HQ-OAR-2007-0121-0005.

86 Henningsen, S., “2007 Panel Discussion on Emission Reduction Solutions for Marine Vessels; Engine Technologies” presentation by MAN B&W at the Clean Sh ips: Advanced Technology for Clean Air Conference, February 8, 2007, Docket ID EPA-HQ-OAR-2007-0121-0031.

87 Weisser, G., “Emission Reduction Solutions for Marine Vesse ls – Wartsila Perspective” presentation by Wartsila at the Clean Ships: Advanced Technol ogy for Clean Air Conference, February 8, 2007, Docket ID EPA-HQ-OAR2007-0121-0032.

88 “DEC SCR Convertor System,” Muenters, May 1, 2006 , Docket ID EPA-HQ-OAR-2007-0121-0013

. 89 Hagström, U., “Humid Air Motor (HAM) and Selective Ca talytic Reduction (SCR),” Viking Line, presented at Air Pollution from Ships, May 24-26, 2005, Docket ID EPA-HQ-OAR-2007-0121-0027.

90 “Reference List - SINOx® Systems, ” Argillon, December 2 006, Docket ID EPA-HQ -OAR-2007-0 121-0035.39 in a wide range of ship types including ferries, supply ships, ro ros (roll-on roll-off), tankers, container ships, icebreakers, cargo sh ips, workboats, cruise ships, and foreign navy vessels for both propulsion and auxiliary engines. These SCR units are being used successfully on slow and medium speed Category 3 propulsion engine s and on Category 2 propulsion and auxiliary engines. The fuel used on ships with SCR systems range s from low sulfur distillate fuel to high sulfur residual fuel. SCR is capable of reduc ing NOx emissions in marine diesel exhaust by more than 90 percent and can have other benefits as well. 92,93, 94 Fuel consumption improvements may also be gained with the use of an SCR system. By relying on the SCR unit for NOx emissions control, the engine can be op timized for better fuel consumption, rather than for low NOx emissions. When an oxidation catalyst is used in conjunction with the SCR unit, significant reductions in HC, CO, and PM may also be achieved. The SCR unit attenuates sound, so it may use the space on the vessel that w ould normally hold a large muffler generally referred to as an exhaust gas silencer. We To the extent that SCR has been used in additional marine applications, we request further information on the use of SCR on marine vessels and the potential emissions emission reductions that may be have been achieved. We also request comment on the durability, packaging, and cost of these systems.

An SCR catalyst reduces nitrogen oxides to elemental nitrogen (N 2 ) and water by using a small amount of ammonia (NH 3 ) as the reducing agent. The most-common method for supplying ammonia to the SCR catalyst is to in ject an aqueous urea-water solution into the exhaust stream. In the presence of high-temper ature exhaust gases (>200 °C), the urea in the injected solution hydrolyzes to form NH 3 . The NH 3 is stored on the surface of the SCR catalyst where it is used to complete the NOx reduction re action. In theory, it is possible to achieve 100 percent NOx conversion if the exhaust temper ature is high enough and the catalyst is large enough. Low temperature NOx conversion effici ency can be improved through use of an oxidation catalyst upstream of the SCR catal yst to promote the conversion of NO to NO 2

. Because the reduction of NOx can be rate lim ited by NO reductions, converting some of the NO
to NO 2 also allows manufacturers to use a smaller reactor.

Manufacturers report minimum exhaust temperatur es for SCR units to be in the range of 250 to 300°C, depending on the catalyst system design and fuel sulfur level. 95,96,97 Below this temperature, the vanadium-oxide catalyst in th e SCR unit would not be hot enough to efficiently

91 “Reference List January 2005 Marine Applications,” Hug Engineering, January 2005, Docket ID EPA-HQ-OAR2007-0121-0036.

92 Heim, K., “Future Emission Legislation and Reduction Po ssibilities,” Wärtsilä, presented at CIMAC Circle 2006, September 28, 2006, Docket ID EPA-HQ-OAR-2007-0121-0017.

93 Argillon, “Exhaust Gas Aftertreat ment Systems; SCR – The Most Effective Technology for NOx Reduction,” presented at Motor Ship Marine Propulsion Conference, May 7-8, 2003, Docket ID EPA-HQ-OAR-2007-0121-
0010.

94 Holmström, Per, “Selective Catalytic Reduction,” presen tation by Munters at Clean Ships: Advanced Technology for Clean Air, February 7-9, 2007, Docket ID EPA-HQ-OAR-2007-0121-0013.

95 Rasmussen, K., Ellegasrd, L., Hanafusa, M., Shimada, K ., “Large Scale SCR Applicatio n on Diesel Power Plant,” CIMAC paper number 179, presented at International Council on Combustion Engines Congress, 2004, Docket ID EPA-HQ-OAR-2007-0121-0007.

96 “Munters SCR ConverterTM System,” downloaded from www.munters.com, November 21, 2006, Docket ID EPAHQ-OAR-2007-0121-0023.

97 Argillon, “Exhaust Gas Aftertreat ment Systems; SCR – The Most Effective Technology for NOx Reduction,” presented at Motor Ship Marine Propulsion Conference, May 7-8, 2003, Docket ID EPA-HQ-OAR-2007-0121-
0010.40 reduce NOx. With very low sulfur fuels, a hi ghly reactive oxidation catalyst can be used upstream of the SCR reactor to convert NO to NO 2 . NO 2 reacts in the SCR catalyst at lower temperatures than NO; therefore, the oxidation catalyst lowers the exhaust temperature at which the SCR unit is effective. However, as the su lfur concentration increases, a less reactive oxidation catalyst must be used to prevent exce ssive formation of sulfat es and poisoning of the oxidation catalyst. When operating on marine distilla te fuel with a sulfur level of 1,000 ppm, the minimum exhaust temperature for effective reduc tions through a current SCR system would be on the order of 270°C. On typical heavy fuel oils , which have sulfur concentrations on the order of 2.5 percent, the exhaust temperature would need to be about 300°C due to high sulfur concentrations. We request comment on the re lationship between SCR operating temperatures and the quality of the fuel used.

SCR can be operated in exhaust streams at or above 500°C before heat-related degradation of the catalyst becomes significant. This maximum exhaust temperature is sufficient for use with Category 3 marine engines. Exhaus t valve temperatures are generally maintained below 450°C to minimize high temperature corr osion and fouling caused by vanadium and sodium present in residual fuel.

Modern SCR systems should be able to achieve very high NOx conversion for all operation covered by the E3 test cycle, which in cludes power levels from 25 to 100 percent. A properly designed system can generally maintain exhaust temperatures high enough at these power levels to ensure proper functioning of the improved SCR catalysts. However, exhaust temperatures at lower power levels on current vessels may be below the minimum temperature threshold for SCR systems, especially when operate d on high sulfur fuels. We believe that it is important that NOx emission contro l is achieved even at low power due to the concern that much of the engine operation that occu rs near the shore may be at less than 25 percent power. As described in Section VII.A.2, we are considering the need for cha nges to the test cycle or other supplemental requirements to account for the fact that the current test cy cle does not include any operation below 25 percent power. We reque st comment on engine power levels, and corresponding exhaust temperature profiles, wh en maneuvering, operating at low speeds, or during other operation near shore.

We believe there are several approaches that can be used to ensure that the exhaust temperature during low power operation is su fficiently high for the SCR unit to function properly. By positioning the SCR system ahead of the turbocharger, the heat to the SCR system can be maximized. This approach was used with vessels equipped with sl ow-speed engines that operated at low loads near the coast. 98 Exhaust temperatures coul d be increased by adjusting engine parameters, such as reduced charge air cooling and modified injection timing. In one case, SCR was used on a short passage car ferr y which originally had exhaust temperatures below 200°C when the engine was operated at low load. 99 When the SCR unit was installed, controls were placed on the intercooler in the ai r intake system. By reducing the cooling on the intake air, the exhaust temperature was increased to be within the ope rating range of the SCR unit, even during low power operation. In a ship using multiple propulsion engines, one or more

98 MAN B&W, “Emission Control Two-St roke Low-Speed Diesel Engines,” December 1996, Dock et ID EPA-HQOAR-2007-0121-0020.

99 “NOx Emissions from M/V Hamlet,” Data provided to W. Charmley, U.S. EPA. by P. Holmström, DEC Marine, February 5, 2007, Docket ID EPA-HQ-OAR-2007-0121-0015.41 engines could be shut down such that the rema ining engine or engine s are operating at higher power. Another approach to increase the exhaus t temperature could be to use burner systems during low power operation. We request comment If commenters have additional information on the feasibility of using SCR for effective NOx emission cont rol at low power operation , we request that this information be submitted for our consideration as we continue developing proposed standards for Category 3 marine engines

.

SCR grade urea is a widely used industri al chemical around the world. Although an infrastructure for widespread transportation, stor age, and dispensing of SCR-grade urea does not currently exist in most places, we believe that it would develop as needed based on market forces. Concerning urea production capacity, the U.S. has more-than-sufficient capacity to meet the additional needs of the marine engines. Currently, the U.S. consumes 14.7 million tons of ammonia resources per year, and relies on imports for 41 percent of that total (of which, urea is the principal derivative). In 2005, domestic am monia producers operated their plants at 66 percent of rated capacity, resulting in 4.5 million tons of reserve production capacity. 100 Thus we do not project that urea cost or supply will be an issue. As an alternative, one study looked at using hydrocarbons distilled from the marine fuel oil as a reductant for an SCR unit. 101 We request comment on any issues rela ted using urea, or any other reduc tant, on ships such as costs, on-board storage requirements, and supply infrastructure.



### C. PM and SOx Control
As discussed above, we are considering PM and SOx emission cont rol approaches based on both fuel sulfur limits and perf ormance based requirements. This section discusses traditional in-cylinder emission controls, fuel qu ality, and exhaust gas scrubbing technology.



### 1. In-Cylinder Controls
For typical diesel engines operating on distillate fuel, pa rticulate matter formation is primarily the result of incomplete combustion of the fuel and lube oil. The traditional in-cylinder technologies discussed above for NOx emission control can be optimized for PM control while simultaneously reducing NOx emissions. If aftertre atment, such as SCR, is used to control NOx, then the in-cylinder technologies can be used primarily for PM reductions. However, the PM reduction through in-cylinder techno logies is limited for engine s operating on high-sulfur fuel because the majority of the PM emissions in this case are due to compounds in the fuel rather than due to incomplete com bustion, as discussed below.



### 2. Fuel Quality

The majority of Category 3 engines are de signed to run on residual fuel which has the highest viscosity and lowest pr ice of the petroleum fuel grad es. Residual fuels are known by several names including heavy fuel oil (HFO), bunker C fuel, and mari ne fuel oil. This fuel is made from the very end products of the oil refi ning process, formulated from residues remaining in the primary distilling stages of the refining process. It has high content of ash, metals,

100 U.S. Department of the Interior, "Mineral Commodity Summaries 2006," page 118, U.S. Geological Survey, January 13, 2006, Docket ID EPA-HQ-OAR-2007-0121-0022.

101 Tokunaga, Y., Kiyotaki, G., “Development of NOx Reduction System for Marine Diesel Engines by SCR using Liquid Hydrocarbon Distilled from Fuel Oil as Reductan t,” CIMAC paper number 63, presented at International Council on Combustion Engines Congress, 2004, Docket ID EPA-HQ-OAR-2007-0121-0002.42 nitrogen, and sulfur that increase emissions of exhaust PM pollutants. Typical residual fuel contains about 2.7 percent sulfur, but may have a sulfur content as high as 4.5 percent.

When a diesel engine is operating on very lo w sulfur distillate fu el, 80 to 90 percent of
the PM in the exhaust is unburne d hydrocarbons from the fuel and lubricating oil and carbon soot. When residual fuel is used, only about 25 to 35 percent of the PM from the engine is made up of unburned hydrocarbon compounds. 102,103,104 In this case, the majority of the PM from the engine is made up of sulfur, metal, and ash comp onents originating from the fuel itself. On a mass basis, the vast majority of this fuel-based PM is due to the sulfur which oxidizes in the combustion process and associates with water to form an aqueous solution of sulfuric acid, known as sulfate PM. Data suggest that about two percent of the sulfur in the fuel is converted directly to sulfate PM. 105,106 The rest of the sulfur in the fuel forms SOx emissions. These SOx emissions lead to indirect PM formation in the atmosphere.

We believe that substantial PM and SOx re ductions could be achieved through the use of lower sulfur fuel. Using a residu al fuel with a lower sulfur c ontent would reduce the fraction of PM from sulfate formation. One study showed a decrease of PM emissions from more than 1.0 g/kW-hr on 2.4 percent sulfur fuel to less than 0.5 g/kW-hr with 0.8 percent sulfur fuel for a medium-speed generator engine on a ship. 107 Using distillate fuel would likely have further
reduced sulfur-based emissions and PM emi ssions from ash and metals. Another study compared PM emissions from a large 2-stroke mari ne engine on both low sulf ur residual fuel oil and marine distillate oil and reporte d about a 70 percent reduction in PM. 108 The simpler
molecular structure of distillate fuel may result in more comple te combustion and reduced levels of carbonaceous PM (soot and heavy hydrocarbons). Because SOx emissions are directly related to the concentration of sulfur in the fuel, a given percent reduction in sulfur in the fuel would be expected to result in about the same percent re duction in SOx emissions from the engine. We request comment on the potential PM and SOx emission reductions th at could be achieved through the use of lower sulfur residual fuel or through the use of distillate fuel in Category 3 marine engines.

In general, engines that are designed to ope rate on residual fuel are capable of operating on distillate fuel. For example, if the engine is to be shut down for maintena nce, distillate fuel is typically used to flush out the fuel system. There are some issues that would need to be

102 Paro, D., “Effective, Evolving, and Envisaged Emission Control Technologies for Marine Propulsion Engines,” presentation from Wartsila to EPA on September 6, 2001, Docket ID EPA-HQ-OAR-2007-0121-0028.

103 Koehler, H., “Field Experience with Considerably Reduced NOx and Smoke Emissions,” MAN B&W, 2004, Docket ID EPA-HQ-OAR-2007-0121-0019.

104 Heim, K., “Future Emission Legislation and Reduction Possibilities,” presentation by Wartsila at the CIMAC Circle 2006, September 28, 2006, Docket ID EPA-HQ-OAR-2007-0121-0017.

105 “Emission Factors for Compression Ignition Nonroad Engines Operated on No. 2 Highway and Nonroad Diesel Fuel,” U.S. EPA, EPA420-R-98-001, March 1998, Docket ID EPA-HQ-OAR-2007-0121-0025.

106 Lyyranen, J., Jokiniemi, J., Kauppinen, E., Joutsensaari, J., “Aerosol Characterization in Medium-Speed DieselEngines Operating with Heavy Fuel Oils,” Aerosol Science Vol. 30, No. 6, pp. 771-784, 1999, Docket ID EPA-HQOAR-2007-0121-0009.

107 Maeda, K., Takasaki, K., Masuda, K., Tsuda, M., Yasu nari, M., “Measurement of PM Emission from Marine Diesel Engines,” CIMAC paper number 107 presented at International Council on Combustion Engines Congress, 2004, Docket ID EPA-HQ-OAR-2007-0121-0004.

108 Kasper, A., Aufdenblatten, S., Forss, A., Mohr, M., Burtscher, H., “Particulate Emissions from a Low-Speed Marine Diesel Engine,” Aerosol Science and Technology , 41:24-32, 2007.43 addressed for operating engines on di stillate fuel that were desi gned primarily for use on residual fuel. Switching to distillate fuel requires 20 to 60 minutes, depe nding on how slowly the operator wants to cool the fuel temperatures. According to engine manufacturers, switching
from a heated residual fuel to an unheated dist illate too quickly could cause damage to fuel pumps. These fuel pumps would need to be de signed to operate on both fuels if a fuel-switching strategy were employed. Separate fuel tanks would be needed for distillate fuel with sufficient capacity for potentially extended operation on this fu el. It is common for ships to have several fuel tanks today to accommodate the variety in di fferent grades of residual fuel which may be incompatible with each other and, therefore, requ ire segregation. Also, different lubricating oil is used with each fuel type. We believe that prop erly designed ships would be able to operate on distillate fuel either under a fuel-switching stra tegy or for extended use. We request comment on the practical implications of operating ships on either lower sulfur residual or distillate fuel for
extended use.

Fuel quality may also affect NOx emissions . Residual fuels have nitrogen bound into the
fuel at a concentration on the order of 0.3 to 0.4 we ight percent. In cont rast, marine distillate fuel has about a 0.02 to 0.06 weight percent concentr ation of nitrogen in the fuel. Approximately half of nitrogen in the fuel will oxidize to form NOx in a marine diesel engine. 109 In addition, the ignition quality of the fuel ma y be worse for residual fuel than for distillate fuel which can
affect NOx emissions. These effects are reflect ed in the MARPOL NOx technical code which allows an upward adjustment of 10 percent for NOx, under certain circumstances, when the engine is tested on residual fu el. We request comment on the e ffect of using residual fuel on NOx emissions, both due to nitrogen in the fuel and any impacts of fuel quality on ignition-delay
or other combusti on characteristics.

There are several types of processes refine ries use to remove sulfur from fuels.
Traditional sulfur removal te chnologies include installing a hydrocracker upstream, or a hydrotreater upstream or downstream, of the fluidi zed catalytic cracker (FCC) unit. Due to high refinery production costs, it is not likely that much new vol ume of residual fuel will be desulfurized to create 1,000 ppm heavy fuel oil. It is more likely that additional distillate fuel may be produced by cracking existing residual fuels or that blends of high and low sulfur fuels will be used. Some existing low sulfur residua l fuel is already produced, though the volume is probably insufficient to fully meet fuel vol ume requirements for both ships and land-based applications subject to local sulfur emissi on requirements. We request comment on the availability of low sulfur marine fuels.



### 3. Exhaust Gas Scrubbers
Another approach to reduce PM and SOx em issions is to use seawater scrubbers.
Seawater scrubbers are an aftertreatment technol ogy that uses the seawater’s ability to absorb
SO 2 . In the scrubber, the exhaust gases are br ought into contact w ith seawater. The SO 2 in the exhaust reacts with oxygen to produc e sulfur trioxide that subseque ntly reacts with water to yield
sulfuric acid. The sulfuric acid in the water then r eacts with carbonate (and other salts) in the seawater to form sulfates which may be rem oved from the exhaust. The carbonate also directionally neutra lizes the pH of the sulfuric acid.

109 Takasaki, K., Tayama, K., Tanaka, H., Baba, S., Tajima, H., Strom, A., “NOx Emission from Bunker Fuel Combustion,” CIMAC paper number 87, presented at International Council on Combustion Engines Congress, 2004, Docket ID EPA-HQ-OAR-2007-0121-0003.44 A scrubber system does not necessarily need to use sea water. An alternative approach is to circulate fresh water through the scrubber system. In this design, the pH of the wash water is
monitored and additional caustic so lution is added as necessary. If the pH becomes too low, the
water will not adsorb absorb any further sulfur. During typical operation, a small amount of wash water is bled out of the system and fresh water is added to maintain volume. This prevents excessive build-up of contaminants in the wash water.

Water may be sprayed into the exhaust stream, or the exhaust gasses may be routed through a water bath. As the cooled exhaust ga s rises out the stack, de misters are used to separate water droplets that may be entrained in the exhaust. The cleaned exhaust passes out of the scrubber through the top while the water, containing sulfates , is drained out through the bottom. Recent demonstration projects have shown scrubbers are be capable of reducing SOx emissions on the order of 95 percent. 110 Today, exhaust gas silencers are used on ships to muffle
noise from the exhaust. Seawater scrubbers would act as mufflers making the exhaust gas silencers unnecessary. New seawater scrubber designs are not much larger than exhaust gas silencers already used on ships, and could be pa ckaged in the space formerly used by an exhaust gas silencer. 111 We request comment on the effectiveness of further experience with seawater scrubbers and on the practical issues related to installing scrubbers on ships, including space
constraints and costs.

Exhaust gas scrubbers can achieve reductions in particulate matter as well. By removing sulfur from the exhaust, the scrubber removes mo st of the direct sulf ate PM. As discussed above, sulfates are a large porti on of the PM from ships operati ng on high sulfur fuels. By reducing the SOx emissions, the scru bber will also control much of the secondary PM formed in the atmosphere from SOx emissions.

Simply mixing alkaline water in the exhaus t does not necessarily remove much of the carbonaceous PM, ash, or metals in the exhaust. While SO 2 associates with the wash water, particles can only be washed out of the exhaust through direct contac t with the water. In simple scrubber designs, much of the mass of particle s can hide in gas bubbles and escape out the exhaust. Manufacturers have been improving th eir scrubber designs to address carbonaceous soot and other fine particles. Finer water sprays, longer mixing times , and turbulent action would be expected to directionally reduce PM emissions through contact impactions. One scrubber design uses an electric charge on the water to attract particles in the exhaust to the water. Two chambers are used so that both a positive and a negative charge can be used to attract both negatively-charged and positively-char ged particles. The manufacturer reports an efficiency of more than 99 percent for the removal for particulate matter and condensable organics in diesel exhaust. 112 Although exhaust gas scrubbers are only used in a few demonstration vessels today, this technology is widely used in land-based applications. We

110 Skawinski, C., “Seawater Scrubbing Advantage,” Presentation by Marine Exhaust Solutions at the Conference for Emission Abatement Technology on Ships held by the Swedish Maritime Administration, May 24-26, 2005, Docket ID EPA-HQ-OAR-2007-0121-0021.

111 “Krystallon Seawater Scrubber,” downloaded from www.krystallon.com on February 14, 2007, Docket ID EPAHQ-OAR-2007-0121-0018.

112 “Cloud Chamber Scrubber Performan ce Results for Diesel Exhaust,” Tri- Mer Corporation, April 14, 2005, Docket ID EPA-HQ-OAR-2007-0121-0026.45 request comment on potential PM reductions that could be achieved through the use o f exhaust

gas scrubbers on vessels and how scrubber design impacts the amount of PM that is removed
from the exhaust.

It may be possible to achieve NOx reductions through the use of seawater scrubbers. In a typical scrubber, the water- soluble fraction of NOx (NO 2 ) can combine with the water to form nitrates which are scrubbed out of the exhaust. However, because NO 2 makes up only a small fraction of total NOx, this results in less than a 10 percent reduction in NOx emissions exhausted to atmosphere. 113 Seawater electrolysis systems have been developed which increase the adsorption rate of NOx in the water by oxidizing NO to NO 2 , which is water-soluble. 114 One study used electrolysis in an experimental scru bbing system to remove 90 percent of the NO and nearly all of the NO 2 in the feed gas. 115 We request comment on th e feasibility of achieving significant NOx reductions from Category 3 ma rine engines through the use of seawater scrubbers. We also request comment on the imp act of this technology on nitrate loading and eutrophication of surrounding waters.

Water-soluble components of the exhaust gas such as SO 2 , SO 3 , and NO 2 form sulfates and nitrates that are dumped ove rboard in the discharge water. Scrubber wash water also includes suspended solids, heavy metals, hydrocarbons and PAHs. Before the scrubber water is discharged, it may be processed to remove solid particles through several approaches. Heavier particles may be trapped in a settling or sludge tank for disposal. The removal process may include cyclone technology similar to that used to separate water from residual fuel prior to delivery to the engine. Howeve r, depending on particle size dist ribution and particle density, settling tanks and hydrodynamic separation may not effectively remove all suspended solids. Other approaches include filtration and flocculati on techniques. Flocculation, which is used in many waste water treatment plants, refers to addi ng a chemical agent to the water that will cause the fine particles to aggregate so that they may be filtered out. Sludge separated from the
scrubber water would be stored on board until it is disposed of at proper facilities.

We request comment on appropriate waste di scharge limits for scrubber water and how
these limits should be defined. We are concerned that if limits are based on the concentration of the pollutants in the water, then the standards co uld be met simply by diluting the effluent before it is discharged. Although diluti ng the discharge water may have some local benefits near the vessel, it would not change the total pollutant load on a given body of water. We request comment on basing limits for waste water pollutant s on engine load, similar to exhaust emission
standards.

113 Skawinski, C., “Seawater Scrubbing Advantage,” Presentation by Marine Exhaust Solutions at the Conference for Emission Abatement Technology on Ships held by the Swedish Maritime Administration, May 24-26, 2005, Docket ID EPA-HQ-OAR-2007-0121-0021.

114 An, S., Nishida, O., “Marine Air Pollution Control System Development Applying Seawater and Electrolyte,” SAE Paper 2002-01-2295, July 2002, Docket ID EPA-HQ-OAR-2007-0121-0024.

115 Houng-Soo, K., “Development of Diesel Engine Emission Control System on NOx and SOx by Seawater Electrolysis,” CIMAC paper number 25 presented at International Council on Combustion Engines Congress, 2004, Docket ID EPA-HQ-OAR-2007-0121-0001.46 

## VII. Certification and Compliance

We In general, we expect generally to continue with retain the certification and compliance program provisions finalized with the Tier 1 standards. These include testing, durability, labeling, maintenance, prohibited acts, etc. However, we believe additional testing and compliance provisions will be necessary for new standards requiring more advanced technology and more challenging calibrations. These changes, as well as other modifications to our certification and compliance provisions, are discussed below.



### A. Testing

1. PM Sampling
In the past, there has been some concern regarding the use of older PM measurement procedures with high sulfur residu al fuels. The primary issue of concern was variability of the PM measurement, which was strongly influen ced by the amount of water bound to sulfur. However, we believe improvements in PM measurement procedures, such as those specified in 40 CFR 1065, have addressed these issu es of measurement variability. The U.S. government recently submitted proposed procedures for PM measurement to IMO. 116 We request comment

on the feasibility of these procedures for accurately measuring PM emissions from Category 3 marine engines operating on residual fuel.



### 2. Off

- Cycle Emissions

Low Power Operation

We are concerned about emission contro l performance when the engine is not operating on the ISO E3 test cycle points. For Categor y 1 and Category 2 engi nes, we adopted “not

- to

exceed” provisions to define an objective measur e to ensure that engines would be reasonably controlling emissions u nder the whole range of expected no rmal operation, as well as the defeat

device prohibition. Since these smaller engines are mass produced for a wide range of vessels used in many different applications, we exp ected “normal operation” for these engines to vary considerably around the id eal propeller curve. Often, Category 3 engines are intended to operate on a propeller curve matched with a propeller fo r custom installation on a specific vessel. However, these engines may have different duty cycles when used with variable pitched propellers or as auxiliary engines. W e remain concerned that Category 3 engines may have higher emissions between test modes , regardless of the intend ed operation of the engine . While the defeat device prov isions prohibit manuf acturers from producing th eir engines to control emissions more effectively operated at established test points than at other points not included in the test, it can be a diffi cult prohibition to enforce. We request comment on how to address
emissions duri ng engine operation not captured by th e certification test duty cycle.

This concern is especially important for Category 3 engines, which generally remain adjustable in use. In other words, shipboard engineers are typically employed to maintain Category 3 engines and would be able to adjust engine calibrations as they deem appropriate. To address this adjustability, w e are considering a requirement for manufacturers to develop emission targets to allow the operator to ensure that the e ngine has been rea djusted to have

116 Measurement Method for Particulate Matter Emitted fr om Marine Engines, submitted by the United States. BLG-WGAP 2, October 2007. Intersessional Meeting of the BLG Working Group on Air Pollution, 2 nd Session.47 performance equivalent to the certified configuration. Without some form of target, it may be very difficult for operators to pr operly adjust their engines to be equivalent to their certified configurations if the operators cannot duplicat e certification test conditions (speed, load, fuel quality, etc.). The emission targets would vary with operating conditions and would include targets for engine speeds other th an the test points speeds. E quivalent control could involve either using of t he same injection timing map for the tested and non

- tested engine speeds, or following a linear interpolation betwee n test points for NOx emissions at non

- test speeds. For example, manufacturers might provide operators with a series of NOx maps that relat e allowable NOx emission levels to various operating paramete rs. Operators would then be required to adjust their engine until it was below the NOx targets. We also request comment on other methods of addressing this adjustability.

In addition, we rema in concerned that low power. Category 3 engines operate at relatively low power levels when they are operati ng in port areas. Ship pilots generally operate engines at reduced power for several miles to appr oach a port, with even lower power levels very
close to shore. Because of the relatively low weighting of the low

- power test modes in the ISO E3 test cycle The ISO E3 and E2 test cycles are used for emission testing of propulsion marine engines. These test cycles are heavily weighted towards high power. Therefore , it is very possible that manufacturers could meet the cycl e-weighted average emission standards without significantly reducing emissions at the low-power modes that are . Because low power operation
is more prevalent for these propulsion engines as when they operate close to commercial ports

. This, of course, has th e potential to reduce , it is important that the emission control strategy be effective at low power operation to maximize on-shore emission benefits. This issue would generally not apply to vessels that rely on multiple engines pr oviding electric-drive propulsion,
since because these engines can be shut down as needed to maintain the desired engine loading

. We are considering a variety of options to address this concern. We could re

- weight the modes of the duty cycle to emphasize low

- power operation. This has several potential drawbacks . For example, we have no information to provide a ba sis for applying different weighting factors. Also, changing the duty cy cle would depart from the historic norm for ma rine engine testing.
This would make it more difficult to make use of past emission data, which is all based on the established modal weighting.

An alternative approach would be to cap emission rates at the two and therefore may not operate at low

- power modes. We could set the cap at th e same level as the emission standard, or
allow for a small variation above the emission st andard. For mechanically controlled engines, such an approach could dictate the overall design of the eng ine. On the other hand, there is increasing use of electronic controls, which would enable the manufacturer to target emission controls specifically for low

- power operation with little or no effect on controlling emissions at higher power settings . We request comment on the need fo r addressing emissions at low power operation and whether and how the test proce dure should be changed to accommodate this operation. See section VI.B for additional disc ussion of low power NOx emissions for engines equipped with exhaust aftertreatment.



### 3. Test Fuel
Appropriate test procedures need to represent in-use ope rating conditions as much as possible, including specification of test fuels consistent with the fu els that compliant engines will
use over their lifetimes. For the Ti er 1 standards, we allow engine testing using distillate fuel,48 even though vessels with Category 3 marine engines primarily use the significantly less expensive residual fuel. This provision is c onsistent with the specifications of the NOx Technical Code. Also, most manufacturers have test facilities designed to test engines using
distillate fuel. Distillate fuel is easier to test with because it does not need to be heated to remain a liquid and manufacturers have in dicated that it is difficult to obtain local permits for testing with residual fuel. However, we believe it is impor tant to specify a test fuel that is consistent
with the in-use fuel with which engines will operate in service. This is especially true for PM measurements. We request comment on the appropria te test fuel for emission testing and if this fuel should be representative on the fuel on whic h a specific engine is designed to operate.

For any NOx measurements from engines ope rating on residual fuel we recognize that there may be emission-related effects due to fuel quality, specifically fuel-bound nitrogen. If the
standards were based on distilla te fuel, we would consider a NOx correction factor to account for the impact of fuel quality when testing on residual fuel. This correction would be useful because of the high levels of nitrogen contained in residu al fuel. Such a correction factor would likely involve measuring fuel-bound nitrogen and correcti ng measured values to what would occur with a nitrogen concentration of 0.4 weight percent. Th is corrected value would be used to determine whether the engine meets emission standards or not. We request comment on the need for corrections and, if so, how the appropr iate corrections would be developed.



### B. On-off Technologies

One of the features of the em ission control technologies that could be used to achieve significant NOx and PM reductions from C3 engines is that they are not integral to the engine and the engine can be operated without them. Aftertreatment systems such as SCR or emission scrubbing, or the use of lower sulfur fuel, require a positive action on the part of the ship owner to make sure the emission control system is in operation or that the appr opriate fuel is used. These types of technologies are of ten called “on-off” technologies.

The increased operating costs of such controls associated with urea or other catalysts or with distillate usage suggest that it may be reas onable to allow these systems to be turned off while a ship is operated on the open ocean, far away from sensitive areas that are affected by ship emissions. In other words, EPA could elect to set geographically-based NOx and PM standards, with one limit that w ould apply when ships are operated within a specified distance from U.S. coasts, and another that would appl y when ships are operated outside those limits.

If EPA were to adopt such an approach, we would need to determine the areas in which ships would have to comply with the standards. We are currently exploring this issue through the air quality modeling for our pr oposed standards. There are othe r issues associated with such an approach, including: the technological feas ibility of by-pass systems and their impacts on the emission control systems when they are not in us e; the level of the sta ndard that would apply when the system is turned off; and how complia nce would be demonstrated. There may also be additional certification requirements fo r ships equipped with such systems.

We request comment on all aspects of this altern ative, especially with regard to how such systems could be designed to en sure no loss of emission reductions.49 

### C. Parameter Adjustment
Given the broad range of ignition properties fo r in-use residual fuels, we expect that our in-use adjustment allowance for Category 3 engine s would result in a broad range of adjustment. We are therefore considering a requirement for op erators to perform a simple field measurement
test to confirm emissions afte r parameter adjustments or main tenance operations, using onboard emission measurement systems with electronic-loggi ng equipment. We expect this issue will be equally important for more advanced engines that rely on water injection or aftertreatment for
emission reductions. Onboard ve rification systems could add signi ficant assurance that engines have properly operating emission controls.

We envision a simpler measurement system th an the type specified in Chapter 6 of the
NOx Technical Code. As we described in the 2003 final rule, we belie ve that onboard emission equipment that is relatively inexpensive and easy to use could verify that an engine is properly adjusted and is operating within the engine manuf acturer’s specifications. Note that Annex VI includes specifications allowing operators to choose to verify emissions through onboard testing, which suggests that Annex VI also envisioned that onboard measurement systems could be of value to operators. We request comment on re quiring onboard verification systems on ships with Category 3 marine engines and on a description of such a system.



### D. Certification of Existing Engines
While we normally require certification only for newly built engines, we are considering emission standards that would apply to remanufactu red engines in the existing fleet. This leads to questions about how one would certify the modi fied engines. We are considering adoption of one or more of the following simplified cer tification procedures for in-use engines:

• Basing certification for any engine on a pre-ex isting certificate if the engine is modified to be the same as a later engine that is al ready certified to the Tier 1 NOx standard.

• Testing in-use engines using portable emissi on measurement equipment, with appropriate consideration for any necessary devia tions in the engine test cycle.

• Broadening the engine family concept for in-u se engines to reduce the amount of testing necessary to certify a range of engines. This would require the same or similar hardware and calibration requirements to ensure that a si ngle test engine can properly represent all the engines in the broader engine family.

• Developing alternatives to the NOx Technical File 117 to simplify the certification burdens for existing vessels while ensuring that th e modified engines and emission components may be appropriately surveyed and inspected.

We request comment on the best appro ach for ensuring compliance from existing engines. We also request comment on the si mplified certification pro cedures listed above.

117 The NOx Technical File, required pursuant to Section 2.4 of the Technical Code on Control of Emissions of Nitrogen Oxides from Marine Diesel Engines, is a record containing details of engine parameters, including components and settings, which may influence the NOx emi ssions of the engine. The NOx Technical File also contains a description of onboard NOx verification procedures required for engine surveys. The NOx Technical File is developed by the engine manufacturer and must be approved by the authority issuing the engine certificate.50 

### E. Other Compliance Issues
In addition to the compliance issues described above we are also seeking comment on to addition issues, described in this section: (1) the a pplication of the standards engines on foreign

flagged vessels that enter U.S. port s ; and (2) whether the standards should apply to gas turbines

or natu ra l gas engines

. We intend to apply the same exemptions to any new tier of Cate gory 3 marine diesel engine standards as currently apply under our Tier 1 program. These exemptions, including the national security exemption, are set out in 40 CFR 94 Subpart J. We will also consider whether to include engines on foreign vessels in the prog ram and whether we should also adopt standards for non-diesel engines such as gas turbine engines.



### 1. Engines on Foreign-Flagged Vessels
Our current federal marine diesel engine standards do not apply to Category 1, 2, and 3 marine diesel engines installed on foreign- flagged vessels. In our 2003 Final Rule we acknowledged the contribution of engines on forei gn-flagged vessels to U. S. air pollution but did not apply federal standards to foreign vessels (see 68 FR 9759, February 28, 2003). This section
summarizes the discussion from that 2003 Final Rule. We will continue to evaluate this issue as we develop the proposal for this rule.

Section 213 of the Clean Air Act (42 U.S.C. 7547), authorizes regulation of “new nonroad engine” and “new nonroad vehicle.” Howe ver, Title II of the Clean Air Act does not define either “new nonroad engine” or “new nonroad vehicle.” Secti on 216 defines a “new motor vehicle engine” to include an engine that has been “imported.” EPA modeled the current regulatory definitions of “new nonroad engine” and “new marine engine” at 40 CFR 89.2 and 40 CFR 94.2, respectively, after the statutory definiti ons of “new motor vehi cle engine” and “new
motor vehicle.” This was a reasonable exercise of the discretion provided to EPA by the Clean Air Act to interpret “new nonroad engine” or “new nonroad vehicle.” See Engine Manufacturers
Assoc. v. EPA , 88 F.3d 1075, 1087 (D.C. Cir. 1996).

The 1999 marine diesel engine rule did not apply to marine engines on foreign vessels. 40 CFR 94.1(b)(3). At that time, we conclude d that engines installe d on vessels flagged or registered in another country, that come into the United States temporarily, will not be subject to
the emission standards. At th at time, we believed that they were not considered imported under the U.S. customs law. As a result, we did not ap ply the standards adopted in that rule to those vessels (64 FR 73300, Dec. 29, 1999).

The May 29, 2002 proposed rule for Category 3 marine diesel engines solicited comment on whether to exercise our discretion and modify the definition of a “new marine engine” to find that engine emission standards a pply to foreign vessels that ente r U.S. ports. However, in the February 28, 2003 final rule we determined that we did not need to determine whether we have the discretion to interpret “new” nonroad engine or vessel in such a manner.

Foreign vessels were expected to comply with the MARPOL sta ndards whether or not they were also subject to the equivalent Clean Ai r Act standards being adopted in that final rule. Consequently, we concluded that no significant emission re ductions would be achieved by treating foreign vessels as “new” for purposes of the Tier 1 standards and there would be no significant loss in emission reductions by not incl uding them. Therefore, we did not include51 foreign engines and vessels in our 2003 rulemaking and we did not revise the definition of “new marine engine” at that time.

In this rule we will evalua te under what circumstances we may and should define new nonroad engine and vessel to include foreign engines and vessels. As part of that evaluation, we will also assess the progress made by the intern ational community toward the adoption of new more stringent international consensus standa rds that reflect adva nced emission-control technologies.



### 2. Non-Diesel Engines
Gas turbine engines are internal combustion en gines that can operate using diesel fuel, residual fuel, or natural gas, but do not operate on a compression-ignition or other reciprocating engine cycle. Power is extracted from the co mbustion gas using a rotati ng turbine rather than reciprocating pistons. While gas turbine engine s are used primarily in naval ships, a small number are being used in commerc ial ships. In addition, we have received indication that their use is growing in some applications such as crui se ships and liquid natural gas carriers. As we develop the proposal for this rule we will consider whether it is appropriate to regulate emissions from gas turbine engines and, if so, whether spec ial provisions would be needed for testing and certifying turbine engines. For example, since turbine engines have no cylinders, we may need to address how to apply any re gulatory provisions that depend on a specified value for percylinder displacement. We would welcome any emissions information that is available for turbine engines.

Marine engines have been developed that can operate either on natural gas or a dualfuel. 118 In a dual-fuel application, a mixture of marine diesel oil and natural gas is used for the main engine that provides a means to comply with the low-sulfur fuel requirement. Natural gas engines are especially attractive to vessels that carry a cargo of liquefied petroleum gas due to the readily available fuel supply. Natural gas pow ered engines are simila r to Category 3 marine engines operating on traditional diesel fuels, and we would consider including these engines in this rulemaking.

We request comment on other fuels and engine types that we should consider in the scope of this rulemaking. We also request comments on test procedure or other compliance issues that
would need to be considered for these other fuels and engines.



## VIII. Potential Re gulatory Impacts

A. Emission Inventory

The inventory contribution of Category 3 engine s consists of two parts: emissions that occur in port areas and emissions that occur at various distances from th e coast while vessels are underway. Although the issue of emissions tran sport is common to all of our air pollution control programs , these underway emissions s uggest that Category 3 em issions are different
from emissions from other mobile sources. and resu lt in at least two implications for the analysis

118 Nylund, I., “Status and Potentials of the Gas Engines,” Wartsila, CIMAC paper number 163, presented at International Council on Combustion Engines Congress, 2004, Docket ID EPA-HQ-OAR-2007-0121-0006.52 we will perform for our proposal. First, th e definition of the inventory modeling domain becomes important. In the inventory analysis de scribed below we use a distance of 200 nautical miles from shore (see Figure VIII-1 below and a ssociated text). This distance is reasonable based on both particle dynamics 119 and results from air quality modeling for other programs
which has shown that PM and NOx emissions can be transported significant distances. 120 Second, it will be important to analyze the air quality impacts of these emissions at various
distances to determine how offshore emissions aff ect air quality both along the coasts and inland. We will use the CMAQ model, modified to accomm odate at-sea emissions, to track the impacts of underway emissions and estimate the air quality benefits of the proposal.

This section contains our updated inventory estimates for Category 3 marine engines in
the 200 nautical mile domain and a brief di scussion of our invent ory estimation methodology.



### 1. Estimated Inventory Contribution
Category 3 marine engines contribute to the formation of ground level ozone and concentrations of fine particles in the ambi ent atmosphere. Based on our current emission inventory analysis of U.S. and foreign-flag vessels , we estimate that these engines contributed nearly 6 percent of mobile source NOx, over 10 percent of mobile source PM 2.5 , and about 40 percent of mobile source SO 2 in 2001. We estimate that their contribution will increase to about 34 percent of mobile source NOx, 45 percent of mobile source PM 2.5 , and 94 percent of mobile
source SO 2 by 2030 without further controls on these e ngines. Our current estimates for NOx,
PM 2.5 , SO 2 inventories are set out in Tables VIII-1 through VIII-3. The inventory projections for 2020 and 2030 include the impact of existing emi ssion mobile source an d stationary source control programs previously adopted by EPA (e xcluding the recently adopted MSAT regulations, signed on February 9, 2007 which will have an impact on future highway non-diesel PM 2.5 levels).

119 U.S. EPA. Air Quality Criteria for Particulate Matter (October 2004). U.S. Envir onmental Protection Agency, Washington, DC, EPA 600/P-99/002aF-bF, 2004.

120 U.S. EPA Technical Support Document for the Final Cl ean Air Interstate Rule Air Quality Modeling (March 2005) U.S. Environmental Protection Agency, Washington, DC,53 Table VIII-1: 50-State Annual NOx Baseline Emission Levels for Mobile and Other Source Categories

2001 a 2020 2030 Category

short tons % of
mobile

source % of
total short tons % of
mobile

source % of
total short tons % of
mobile

source % of
total

Commercial Marine (C3) b 744,444 745 ,224 5.7% 3.3% 1,399,834 1, 368,420 23.2% 2
2.8% 11. 5% 3
% 2,076,260 2, 023,974 34.3%
33.7% 17.1% 16
.7% Locomotive 1,118,786 8.6% 5.0% 860,474 14. 2% 3
% 7.1% 854,226 14.1% 7.0%

Recreational Marine Diesel 40,437 0.3% 0.2% 45,477 0.8% 0.4% 48,102 0.8% 0.4%
Commercial Marine (C1 & C2 ) 834,025 6.4% 3.7% 676,154 11. 2% 3
% 5.6% 680,025 11. 2%
3% 5.6%

Land-Based Nonroad Diesel 1,548,236 11.9% 6.9% 678,377 11. 2% 3
% 5.6% 434,466 7.2% 3.6%

Small Nonroad SI 114,319 0.9% 0.5% 114,881 1.9% 0.9% 133,197 2.2% 1.1%
Recreational Marine SI 44,732 0.3% 0. 2% 86,908 1.4% 0.7% 96,143 1.6% 0.8%
SI Recreational Vehicles 5,488 0.0% 0. 0% 17,496 0.3% 0.1% 20,136 0.3% 0.2% Large Nonroad SI (>25hp) 321,098 2.5% 1. 4% 46,319 0.8% 0.4% 46,253 0.8% 0.4%
Aircraft 83,764 0.6% 0.4% 105,133 1.7% 0.9% 118,740 2.0% 1.0% Total Off Highway 4,855,329 4, 856,109 37.5% 21.8% 4,031,054 3, 999,640 66. 7% 6
% 33. 2% 0
% 4,507,547 4, 455,262 74. 4%
2% 37.0% 36
.8% Highway Diesel 3,750,886 28.9% 16.8% 646,961 10. 7% 8
% 5.3% 260,915 4.3% 2. 1% 2%

Highway non-diesel 4,354, 430 33.6% 19.5% 1,361,276 22. 5% 7
% 11.2% 1,289,780 21. 3%
5% 10.6%

Total Highway 8,105,316 62.5% 36.3% 2,008,237 33. 3% 4
% 16. 5% 6
% 1,550,695 25. 6% 8% 12. 7% 8
%
Total Mobile Sources 12,960,645 12,961,425 100% 58.1% 6,039,291 6, 007,877 100% 49. 7% 6
% 6,058,242 6, 005,957 100% 49. 8% 6
% Stationary Point & Area Sour ces 9,355,659 - 41.9% 6,111,866 - 50. 3% 4
% 6,111,866 - 50. 2% 4
%
Total Man-Made Sources 22,316,304 22,317,084 - 100% 12,151,157 12,119,743 - 100% 12,170,108 12,117,823 - 100%

a The locomotive, commercial marine (C1 & C2), and recreati onal marine diesel estimates are for calendar year 2002.

b This category includes emissions from Ca tegory 3 (C3) propulsion en gines and C2/3 auxiliary engines used on ocean-going
vessels.54 Table VIII-2: 50-State Annual PM 2.5 Baseline Emission Levels for Mobile and Other Source Categories

2001 a 2020 2030 Category

short tons % of
mobile

source % of
total short tons % of
mobile

source % of
total short tons % of
mobile

source % of
total

Commercial Marine (C3) b 54, 599 667 10.9% 2.2% 111,188 110 ,993 33.6% 5.2% 166, 751 161 45.4% 7.6%

Locomotive 29,660 5.9% 1.2% 26,301 8.0% 1.2% 25,109 6.8% 1.1%
Recreational Marine Diesel 1,096 0.2% 0.0% 1,006 0.3% 0.0% 1,140 0.3% 0.1%
Commercial Marine (C1 & C2) 28,730 5.7% 1.2% 22,236 6.7% 1.0% 23,760 6.5% 1.1%
Land-Based Nonroad Diesel 164,180 32.8% 6. 7% 46,075 13.9% 2.1% 17,934 4.9% 0.8%
Small Nonroad SI 25,466 5.1% 1.0% 32,904 10.0% 1.5% 37,878 10.3% 1.7%
Recreational Marine SI 16,837 3.4% 0. 7% 6,367 1.9% 0.3% 6,163 1.7% 0.3%
SI Recreational Vehicles 12,301 2.5% 0. 5% 11,773 3.6% 0.5% 9,953 2.7% 0.5% Large Nonroad SI (>25hp) 1,610 0.3% 0. 1% 2,421 0.7% 0.1% 2,844 0.8% 0.1%
Aircraft 5,664 1.1% 0.2% 7,044 2.1% 0.3% 8,569 2.3% 0.4% Total Off Highway 340, 143 211 68.0% 13.8% 267, 315 120 80.9% 12.4% 300,101 299 ,511 81.8% 13.7%

Highway Diesel 109,952 22.0% 4.5% 15,800 4.8% 0.7% 10,072 2.7% 0.5% Highway non-diesel 50,277 10.0% 2.0% 47,354 14.3% 2.2% 56,734 15.5% 2.6%
Total Highway 160,229 32.0% 6.5% 63, 154 19.1% 2.9% 66,806 18.2% 3.1%
Total Mobile Sources 500, 372 440 100% 20.3% 330, 469 274 100% 15.4% 366, 907 317 100% 16.8% Stationary Point & Area Sources 1,963, 264 - 79.7% 1,817,722 - 84.6% 1,817,722 - 83.2%
Total Man-Made Sources 2,463, 636 7
04 - 100% 2,148,191 2, 147,996 - 100% 2,184, 62 9 0
39 - 100%

a The locomotive, commercial marine (C1 & C2), and recrea tional marine diesel estimates are for calendar year 2002.

b This category includes emissions from Ca tegory 3 (C3) propulsion en gines and C2/3 auxiliary engines used on ocean-going
vessels.55 Table VIII-3: 50-State Annual SO 2 Baseline Emission Levels for Mobile and Other Source Categories

2001 a 2020 2030 Category

short tons % of
mobile

source % of
total short tons % of
mobile

source % of
total short tons % of
mobile

source % of
total

Commercial Marine (C3) b 432,496 457 ,948 41.0%
42.4% 2. 7% 8
% 883,520 932 ,820 92.8%
93.2% 9.6% 10.
1% 1,326,920 1, 398,598 94. 3%
5% 13.8%
14.4% Locomotive 76,727 7. 3% 1
% 0.5% 400 0.0% 0.0% 468 0.0% 0.0%

Recreational Marine Diesel 5,145 0.5% 0.0% 162 0.0% 0.0% 192 0.0% 0.0%
Commercial Marine (C1 & C2) 80,353 7. 6% 4
% 0.5% 3,104 0.3% 0.0% 3,586 0.3% 0.0%

Land-Based Nonroad Diesel 167,615 15. 9%
5% 1.0% 999 0.1% 0.0% 1,078 0.1% 0.0%

Small Nonroad SI 6,710 0.6% 0.0% 8,797 0.9% 0.1% 10,196 0.7% 0.1%
Recreational Marine SI 2,739 0.3% 0. 0% 2,963 0.3% 0.0% 3,142 0.2% 0.0%
SI Recreational Vehicles 1,241 0.1% 0. 0% 2,643 0.3% 0.0% 2,784 0.2% 0.0% Large Nonroad SI (>25hp) 925 0.1% 0. 0% 905 0.1% 0.0% 1,020 0.1% 0.0%
Aircraft 7,890 0.7% 0.0% 9,907 1.0% 0.1% 11,137 0.8% 0.1% Total Off Highway 781,840 807 ,293 74. 1%
7% 4.9% 5
.0% 913,401 962 ,700 95.9%
96.1% 10. 0% 4
% 1,360,523 1, 432,202 96. 6% 8% 14. 1%
8% Highway Diesel 103,632 9. 8% 6
% 0.6% 3,443 0. 4% 3
% 0.0% 4,453 0.3% 0.0%

Highway non-diesel 169,125 16.0%
15.7% 1.0% 35,195 3. 7% 5
% 0.4% 42,709 3. 0% 2
.9% 0.4%

Total Highway 272,757 25. 9% 3% 1.7% 38,638 4.1% 3
.9% 0.4% 47,162 3. 4% 2
% 0.5%

Total Mobile Sources 1,054,597 1, 080,050 100% 6. 5% 7
% 952,039 1,0 01,338 100% 10. 4% 9
% 1,407,685 1, 479,364 100% 14.6%
15.3% Stationary Point & Area Sources 15,057,420 - 93. 5 % 3% 8,215,016 - 89. 6% 1
% 8,215,016 - 85.4%
84.7%
Total Man-Made Sources 16,112,017 16,137,470 - 100% 9,167,055 9, 216,354 - 100% 9,622,701 9, 694,380 - 100%

a The locomotive, commercial marine (C1 & C2), and recreati onal marine diesel estimates are for calendar year 2002.

b This category includes emissions from Ca tegory 3 (C3) propulsion en gines and C2/3 auxiliary engines used on ocean-going
vessels.

The United States is actively engaged in in ternational trade and is frequently visited by ocean-going marine vessels. As shown in Figure II-1, the ports which accommodate these vessels are located along the entire coastline of the United States. Commercial marine vessels, powered by Category 3 marine engines, contribute significantly to the emissions inventory for many U.S. ports. This is illustrated in Table VIII-4 which presents the mobile source inventory contributions of these vessels for several ports. Th e ports in this table were selected to present a sampling over a wide geographic area along the U.S. coasts. In 2005, these twenty ports received approximately 60 percent of the vesse l calls to the U.S. from ships of 10,000 DWT or greater. 121

121 “Vessel Calls at U.S. & World Ports; 2005,” U.S. Mar itime Administration, Office of Statistical and Economic Analysis, April 2006, Docket ID EPA-HQ-OAR-2007-0121-0040.56 Table VIII-4: Contribution of Commercial Marine Vessels a
to Mobile Source Inventories for Selected Ports in 2002

Port Area NOx PM 2.5 SOx
Valdez, AK Seattle, WA Tacoma, WA San Francisco, CA Oakland, CA LA/Long Beach, CA Beaumont, TX Galveston, TX Houston, TX New Orleans, LA South Louisiana, LA Miami, FL Port Everglades, FL Jacksonville, FL Savannah, GA Charleston, SC Wilmington, NC Baltimore, MD New York/New Jersey Boston, MA 4%
10%
20%
1%
8%
5%
6% 5%
3%
14%
12%
13%
9% 5%
24%
22%
7% 12%
4%
4% 10%
20%
38%
1%
14%
10%
20%
12%
10%
24%
24%
25%
20%
11%
39%
33%
16%
27%
9% 5% 43%
56%
74%
31%
80%
71%
55%
47%
41%
59%
58%
66% 56%
52%
80%
87%
73%
69% 39%
30%

b This category includes emissions from Category 3 (C3) propulsion engines and C2/3 auxiliary engines used on ocean-going vessels.

Currently, more than 40 major U.S. deep sea po rts are located in areas that are designated

as being in nonattainment for either or both the 8

- hour ozone NAAQS and PM 2.5 NAAQS. Many ports are located in areas rated as class I federal areas for visibility impairment and regional haze. It should be noted that emissions from ocean

- going vessels are not simply a localized problem related only to cities that ha ve commercial ports. Virtually all U.S. coastal areas are affected by emissions from ships that transit between those por ts, using shipping lanes
that are close to land. Many of these coastal a reas also have high popul ation densities. For example, Santa Barbara, which has no comme rcial port, estimates that engines on ocean

- going marine vessels currently contribute about 37 percent of total NOx in their area. 122 These emissions are from ships tha t transit the area, and “are comparable to (even slightly larger than) the amount of NOx produced onshore by cars and tr uck.” By 2015 these emissions are expected to increase 67 percent, contri buting 61 percent of Santa Barb ara’s total NOx emissions. This mix of emission sources led Santa Barbara to point ou t that they will be unable to meet air quality standards for ozone without signi ficant emission reductions from these vessels, even if they completely eliminate all other sources of pollution. Interpor t emissions from OGV also contribute to other environmental problems, af fecting sensitive marine and land ecosystems.



### 2. Inventory Calculation Methodology
The exhaust emission inventories presented a bove for commercial ma rine vessels, with Category 3 marine engines, incl ude emissions from vessels in- port and from vessels engaged in interport transit. This section gives a genera l overview of the methodology used to estimate the

122 Memorandum to Docket A

– 2001

– 11 from Jean

- Marie Revelt, Santa Barbara Coun ty Air Quality News, Issue 62, July

- August 2001 and other materials provided to EPA by Santa Barbara County,’’ March 14, 2002.57 emission contribution these vessels. A more detailed description of this inventory analysis is available in the public docket. 123

For the purposes of this anal ysis, in-port operation includes cruising, reduced speed zone, maneuvering, and hotelling. The in-port analysis includes operation out to a 25 nautical mile radius from the entrance to the port. Interport op eration includes ship traffic, within the U.S. Exclusive Economic Zone (EEZ), not included as part of the port emissions analysis. In general,
the EEZ extends to 200 nautical miles from the U.S. coast. Exceptions include geographic regions near Canada, Mexico and the Bahama s where the EEZ extends less than 200 nautical
miles from the U.S. coast.

The port inventories are based on detailed emi ssion estimates for eleven specific ports. The port inventories were estimated using activity data for that port (number of port calls, vessel types and typical times in differe nt operating modes) and an em ission factor for each mode. Emission estimates for all other commercial ports were developed by matching each of the other commercial ports to one of the eleven specific po rts. Matching was base d on characteristics of port activity, such as predominant vessel types, harbor craft and region of the country. The detailed port emissions were then scaled for the other commercial ports based on relative port activity. 124 An exception to this is that detailed po rt inventories for fourteen California ports were provided by the Californi a Air Resources Board (ARB).

To calculate the mobile fractions in Table VIII-4, we compared commercial marine port inventory estimates described a bove to county-level mobile sour ce emission estimates developed in support of the recent rulemaking for na tional PM ambient air quality standards. 125 Both propulsion engines and auxiliary engines are included in thes e estimates. The county-level inventories were adjusted to include the updated emissions estim ates for commercial marine
vessels.

Recently, the California Air Resources Board (ARB) sponsored the development of new national inventory estimates for Category 3 marine engines. 126 The new approach captures actual interport activity, by using information on ship moveme nts, ship attributes, and the
distances of routes. We believe that this me thodology is an improvement over past evaluations of interport shipping emissions which were base d on estimates of ton-miles of cargo moved. The new methodology captures ship traffic more comple tely which results in much higher estimates
of total emissions from commercial marine vessels engaged in interport traffic within the U.S.
EEZ.

123 “Development of Inventories for Commercial Marine Vessels with Category 3 Engines,” U.S. EPA, September October 2007.

124 Browning, L., Hartley, S., Lindhjem, C., Hoats, A., “C ommercial Marine Port Inventory Development; Baseline Inventories,” prepared by ICF International and Environ for the U.S. Environmental Protection Agency, September 2006, Docket ID EPA-HQ-OAR-2007-0121-0037.

125 Regulatory Impact Analysis for the Review of the Pa rticulate Matter National Ambient Air Quality Standards, EPA Docket: EPA-HQ-OAR-2006-0834-0048.3.

126 Corbett, J., Ph.D., Wang, C., Ph.D., Firestone, J., Ph .D, “Estimation, Validation, and Forecasts of Regional Commercial Marine Vessel Inventories, Tasks 1 and 2: Baseline Inventory and Ports Comparison; Final Report,” University of Delaware, May 3, 2006, Available electronically at http://www. arb.ca.gov/research/s eca/jctask12.pdf, Docket ID EPA-HQ-OAR-2007-0121-0038.58 Our emission inventory estimates for inter port traffic are based on the ARB-sponsored study with four primary modifications. 127,128 First, we use only the interport traffic estimates from the study and rely on our own, more detail ed, analysis of in-port emissions. Second, we modified the geographic boundaries of the inventory to align with the U.S. EEZ. Third, we use adjusted emission factors for PM emissions to be tter reflect the sum of available PM emissions data from engines on marine vessels.

The detailed inventory studies described above were performed for 2002. To calculate emission inventories for future years, we applied separate growth rates for the West Coast, Gulf Coast, East Coast, and Great Lakes. Thes e emission inventory growth estimates were determined based on economic growth projections of trade between the United States and other regions of the world. 129 In contrast, the ARB-sponsored st udy looks at a range of growth rates based on extrapolations of histor ical growth in installed power. 130 The approach used by EPA is
more conservative in that it uses lower growth rate projections.

The inventory estimates include emissions fr om both U.S. flagged vessels and foreign flagged vessels. The majority of the ship operation near the U.S. coast is from ships that are not registered in the United States. According to the U.S. Maritime Administration, in 2005, approximately 87 percent of the calls by ocean -going vessels (10,000 dead weight tons or greater) at U.S. ports were made by foreign vessels. 131

This inventory analysis in cludes emissions from Categor y 3 propulsion engines and the Category 2 and 3 auxiliary engines used on these vessels. Based on our emissions inventory analysis, auxiliary engines contribute approximately half of the exhaust emissions from vessels in port. In contrast, auxiliary engines only represent about 4 pe rcent of the exhaust emissions from ships engaged in interport traffic.

The exhaust emission inventory for commerci al marine vessels with Category 3 marine engines includes operation th at extends out to 200 nautical miles from shore. Considering all emissions from ships operating in the U.S. EEZ, emissions in ports contribute to less than 20 percent of the total inventory. However, we r ecognize that emissions closer to shore are more likely to impact human health and welfare because of their proximity to human populations. We have initiated efforts to perform air quality mo deling to quantify these imp acts. The air quality modeling will consider transport of emissions over the ocean, meteorological data, population densities, emissions from other sources, and othe r relevant information. We request comment on

127 “Recalculation of Baseline and 2005 Emissions and Fuel Consumption,” memorandum from Lou Browning, ICF and Chris Lindhjem and Lyndsey Parker, Environ, to Penny Carey, Mike Samulski, and Russ Smith, U.S. EPA, July 19, 2007.

128 “U.S. and Regional Totals of Marine Vessel Emissions and Fuel Consumption under WA 0-2 Tasks 6 and 7,” draft memorandum from Abby Hoats and Chris Lindhjem, Environ, to Lou Browning, ICF International, April 23,
2007.

129 “RTI Estimates of Growth in Bunker Fuel Consumption,” memorandum from Michael Gallaher and Martin Ross, RTI International, to Barry Garelick and Russ Smith, U. S. EPA, April 24, 2006, Docket ID EPA-HQ-OAR-2007-
0121-0039.

130 Corbett, J., Ph.D., Wang, C., Ph.D., “Estimation, Validation, and Forecasts of Regional Commercial Marine Vessel Inventories, Tasks 3 and 4: Forecast Inventories for 2010 and 2020; Final Report,” University of Delaware, May 3, 2006, Docket ID EPA-HQ-OAR-2007-0121-0012.

131 “Vessel Calls at U.S. & World Ports; 2005,” U.S. Mar itime Administration, Office of Statistical and Economic Analysis, April 2006, Docket ID EPA-HQ-OAR-2007-0121-0040.59 the methodology used to develop exhaust inventor y estimates for ships with Category 3 engines operating near the U.S. coast.

As discussed above, the national inventor ies presented here ar e for the Exclusive
Economic Zone around the 50 states. Note that the ship traffic in the EEZ includes not only direct movements to and from U.S. ports, but also movements up and down the coast. The boundaries for the EEZ are presented in Figure VIII-1.61 Figure VIII-1: Regions of U.S. EEZ us ed for Category 3 Inventory Analysis62 Table VIII-5 presents the 2002 national e xhaust emission inventory for commercial marine vessels, with Category 3 marine engines, subdivided into the seven regions shown in the above figure. The Alaska and Hawaii regions contribute to roughly one -fifth of the national emissions inventory. The inventory for the Alas ka EEZ includes emissions from ships on a great circle route, along the Aleutian Islands, between Asia and the U.S. West Coast. Therefore, eastern Alaska, which includes most of the state population, is pres ented separately in the table below. The Hawaii EEZ includes major shipping lanes across the Pacific that pass near the
Hawaiian isles.

Table VIII-5: 2002 Regional U.S. Emi ssions from Commercial Marine Vessels a [tons/yr]

Region NOx [short tons] PM 2.5 [short tons] SOx [short tons]
South Pacific 116,057 8,283 62,944 North Pacific 28,941 2,205 16,469 East Coast 243,261 17,901 153,597 Gulf Coast 192,130 14,374 110,382 Alaska (east) 20,078 1,458 11,037 Alaska (west) 66,768 4,799 35,998 Hawaii 60,501 4,372 32,970 Great Lakes (U.S. only) 16,708 1,207 9,098 Great Lakes (Canada only) 5,621 405 3,043 Total (using U.S. only Great Lakes) 744,444 54,599 432,496

a This category includes emissions from Category 3 (C3) propulsion engines and C2/3 auxiliary engines used on ocean-going vessels.



### B. Potential Costs
The emission-control technologies we are co nsidering for Category 3 marine engines are already in development or in commercial use in some marine applications . The draft Regulatory Impact Analysis 132 for the May 29, 2002 proposed rulemaking for Category 3 marine engines (67 FR 37548) included an analysis of regulator y alternatives which including advanced technologies. To estimate costs of this prospectiv e emissions control progra m, we expect to start with cost estimates that were developed as part of that regulatory analysis. We will modify these
costs as needed to take into account advances in technology, changes in cost structure, and comments received on this ANPRM. We encourag e commenters to review the information covering all aspects of engine co sts in the regulatory impact documents for the earlier Category 3 rulemaking and to provide comments on cost-related issues. In addition, we are interested in
cost information associated w ith potential retrofitting concepts and in information about any unique costs associated with equipm ent redesign for the marine market.

We will also consider the economics of desu lfurizing residual fuel, using of distillate fuel, and blending high and low sulfur fuels. Due to high refinery pr oduction costs, it is not likely that much new volume of residual fuel will be desulfurized. We expect to employ a world wide refinery modeling analysis to estimate th e cost for desulfurizing residual fuel and to estimate the cost for the production of additional dist illate fuel in our anal ysis for different fuel volume scenarios. Additionally, we will estimate scrubbing costs and potential scrubber

132 “Draft Regulatory Support Document: Control of Emi ssions from Compression-Ignition Marine Diesel Engines at or Above 30 Liters per Cylinder,” U.S. Environmental Protection Agency, April, 2002.63 penetration rates for ships, as the use of scrubbers is anothe r method that ships may use to comply, in lieu of using low sulfur fuel. The resu lting fuel cost from our refinery analysis will be compared to the costs from scrubbing and fu el blending to determine the most economical method for complying with the standards for Cate gory 3 marine engines. We request comment on the potential costs of lo w sulfur marine fuels.



## IX. Statutory and Executive Order Reviews

A. Executive Order 12866: Regul atory Planning and Review
Under section (3)(f)(1) Executive Order 12866 (58 FR 51735, October 4, 1993), the Agency must determine whether the regulatory ac tion is “significant” and therefore subject to review by the Office of Management and Budget (OMB) and the requiremen ts of this Executive
Order. This Advance Notice has been sent to the Office of Management and Budget (OMB) for review under EO 12866 and any changes made in response to OMB recommendations have been
documented in the docket for this action.



### B. Paperwork Reduction Act
We will prepare information collection requirements as part of our proposed rule and submit them for approval to the Office of Ma nagement and Budget (OMB) under the Paperwork Reduction Act, 44 U.S.C. 3501 et seq.



### C. Regulatory Flexibility Act
The Regulatory Flexibility Act (RFA) as amended by the Small Business Regulatory Enforcement Fairness Act (SBREFA), requires agenci es to endeavor, consis tent with the objectives of the rule and applicable statutes, to f it regulatory and information requirements to the scale of businesses, organizations, and government al jurisdictions subjec t to their regulations. SBREFA amended the RFA to strengthen its anal ytical and procedural requirements and to ensure that small entities are adequately cons idered during rule development. The Agency accordingly requests comment on the potential impacts on a small entity of the program
described in this notice. These comments w ill help the Agency meet its obligations under SBREFA and will suggest how EPA can minimize the impacts of this rule for small entities that may be adversely impacted.

Depending on the number of small entities identif ied prior to the proposal and the level of any contemplated regulatory action, we may c onvene a Small Business Advocacy Review Panel under section 609(b) of the Regul atory Flexibility Act as ame nded by SBREFA. The purpose of
the Panel would be to collect the advice and reco mmendations of representatives of small entities that could be impacted by the eventual rule. If we determine that a panel is not warranted, we
would intend to work on a less formal ba sis with those small entities identified.

Although we do not believe that this rule wi ll have a significant economic impact on a substantial number of small entities, we are re questing information on small entities potentially impacted by this rulemaking. Information on company size, number of employees, annual revenues and product lines would be especially useful. Confid ential business information may
be submitted as described under SUPPLEMENTARY INFORMATION

.64 

### D. Unfunded Mandates Reform Act

Title II of the Unfunded Mandates Reform Act of 1995 (UMRA), Public Law 104-4, establishes requirements for Federal agencies to assess the effects of th eir regulatory actions on State, local, and tribal governments and the pr ivate sector. Under section 202 of the UMRA, EPA generally must prepare a written statement, including a cost-benefit analysis, for proposed and final rules with "Federal mandates" that may re sult in expenditures to State, local, and tribal governments, in the aggregate, or to the private sector, of $100 million or more in any one year. Before promulgating an EPA rule for which a wr itten statement is needed, section 205 of the UMRA generally requires EPA to identify a nd consider a reasonable number of regulatory alternatives and adopt th e least costly, most cost-effective or least burdensome alternative that achieves the objectives of the rule. The provisi ons of section 205 do not apply when they are inconsistent with applicable la w. Moreover, section 205 allows EP A to adopt an alternative other than the least costly, most cost -effective or least burdensome a lternative if the Administrator publishes with the final rule an explanation w hy that alternative was not adopted. Before EPA establishes any regulatory requirements that may significantly or uniquely affect small governments, including tribal governments, it must have developed under section 203 of the UMRA a small government agency plan. The plan must provide for notifying potentially affected small governments, enabling officials of affected small governments to have meaningful and timely input in the development of EPA re gulatory proposals with significant Federal intergovernmental mandates, and informing, educating, and advising small governments on compliance with the regulatory requirements.

As part of the development of our Notice of Proposed Rulemaking, we will examine the impacts of our proposal with respect to expe cted expenditures by Stat e, local, and tribal governments, in the aggregate, or by the private sector of $100 million or more in any one year.



### E. Executive Order 13132: Federalism

Executive Order 13132, entitled “Federalism” (64 FR 43255, August 10, 1999), requires EPA to develop an accountable process to ensu re “meaningful and timely input by State and local officials in the development of regulatory policies that have federa lism implications.” “Policies that have federalism implications” is defined in the Executive Order to include regulations that have “substanti al direct effects on the States , on the relationship between the national government and the States, or on the di stribution of power and responsibilities among the various levels of government.”

Under Section 6 of Executive Order 13132, EP A may not issue a regulation that has federalism implications, that imposes substantial di rect compliance costs, and that is not required by statute, unless the Federal government provi des the funds necessary to pay the direct compliance costs incurred by State and local gover nments, or EPA consults with State and local officials early in the process of developing th e proposed regulation. EPA also may not issue a regulation that has federalism im plications and that preempts State law, unless the Agency
consults with State and local o fficials early in the process of developing the proposed regulation.

Section 4 of the Executive Order contains additional requirements for rules that preempt State or local law, even if those rule s do not have federalism implications ( i.e ., the rules will not
have substantial direct effects on the States, on the relatio nship between the national government65 and the states, or on the distri bution of power and re sponsibilities among the various levels of government). Those requirements include providi ng all affected State an d local officials notice and an opportunity for appropriate participation in the development of the regulation. If the preemption is not based on express or implied stat utory authority, EPA also must consult, to the extent practicable, with appropria te State and local officials rega rding the conflict between State law and Federally protected interests within the agency’s area of regulatory responsibility.

As part of the development of our Notice of Proposed Rulemaking, we will examine the impacts of our proposal with re spect to the relationship betwee n the national government and the States, or on the distribution of power and responsibilities among the various levels of government, as specified in Executive Order 13132.

In the spirit of Executive Or der 13132, and consistent with EPA policy to promote
communications between EPA and State and lo cal governments, EPA specifically solicits comment on this proposed rule fr om State and local officials.



### F. Executive Order 13175: Consultation and Coordination with Indian Tribal
Governments

Executive Order 13175, entitled “Consultation and Coordination with Indian Tribal Governments” (65 FR 67249, November 9, 2000), requires EPA to develop an accountable process to ensure “meaningful and timely input by tribal officials in the development of regulatory policies that have tribal implications.” “Policies that have tribal implications” is
defined in the Executive Order to include regulations that have “s ubstantial direct effects on one or more Indian tribes, on the relationship between the Federal government and the Indian tribes, or on the distribution of power and responsibilities between the Federal government and Indian
tribes.”

As part of the development of our Notice of Proposed Rulemaking, we will examine the impacts of our proposal with resp ect to tribal implications.



### G. Executive Order 13045: Protection of Children from Environmental Health and Safety Risks

Executive Order 13045, “Protection of Childre n from Environmenta l Health Risks and Safety Risks” (62 FR 19885, April 23, 1997) applies to any rule that: (1) is determined to be “economically significant” as defined under Executive Order 12866, and (2) concerns an environmental health or safety risk that EPA has reason to belie ve may have a disproportionate effect on children. If the regulatory action meet s both criteria, the Agen cy must evaluate the environmental health or safety effects of th e planned rule on childre n, and explain why the planned regulation is preferable to other potentially effective and r easonably feasible alternatives considered by the Agency.

This rule is not subject to the Executive Order because it does not involve decisions on environmental health or safety risks that ma y disproportionately affect children. The EPA believes that the emissions reductions from the strategies proposed in this rulemaking will further improve air quality and will further improve children’s health.66 

### H. Executive Order 13211: Actions that Significantly Affect Energy Supply, Distribution, or Use
Executive Order 13211, “Actions Concerning Re gulations That Significantly Affect Energy Supply, Distribution, or Use” (66 Fe d. Reg. 28355 (May 22, 2001)) requires that we determine whether or not there is a significant impact on the supply of energy caused by our rulemaking. These impacts include: reductions in supply, reductions in production, increases in energy usage, increases in the cost of energy production and di stribution, or other similarly
adverse outcomes. We an ticipate that our proposal will not be a “signifi cant energy action” as defined by this order because we are not reduc ing the supply or production of any fuels or electricity, nor are we increasing the use or cost of energy by more than the stated thresholds. The proposed standards will have for their aim th e reduction of emissions from certain marine engines using either exhaust gas cleaning technol ogy or an alternative grade of marine fuel, and
will have no effect on fuel formulation.



### I. National Technology Transfer Advancement Act

Section 12(d) of the Nati onal Technology Transfer and Advancement Act of 1995 (“NTTAA”), Public Law 104 113, 12(d) (15 U.S. C. 272 note) directs EPA to use voluntary consensus standards in its regul atory activities unless doing so would be inconsistent with applicable law or otherwise impractical. Volunt ary consensus standards are technical standards (e.g., materials specifications, test methods, samp ling procedures, and busi ness practices) that are developed or adopted by voluntary consensus st andards bodies. NTTAA directs EPA to provide Congress, through OMB, explanations when th e Agency decides not to use available and applicable voluntary consensus standards.

As part of the development of our Notice of Proposed Rulemaking, we will examine the availability and use of voluntary consensus standards.



### J. Executive Order 12898: Federal Actions to Address Environmental Justice in Minority Populations and Low-Income Populations
Executive Order (EO) 12898 (59 FR 7629 (Feb. 16, 1994)) establishes federal executive policy on environmental justice. Its main provi sion directs federal agencies, to the greatest extent practicable and permitted by law, to make environmental justice part of their mission by identifying and addressing, as appropriate, disp roportionately high and adverse human health or environmental effects of their programs, policie s, and activities on minority populations and lowincome populations in the United States.

Control of Emissions from New Marine Compression-Ignition Engines at or Above 30 Liters per Cylinder page 105 of 105 - ANPRM

EPA has determined that this proposed rule wi ll not have disproportionately high and adverse
human health or environmental effects on mi nority or low-income populations because it
increases the level of environm ental protection for all affected populations without having any disproportionately high and adve rse human health or environm ental effects on any population, including any minority or low-income population. Rather the opposite as more low-income
individuals tend to live closer to marine ports, and it is these areas that will receive the most benefits in this rule that will reduce emissions of large marine engines.67 List of Subjects
40 CFR Part 9 Reporting and recordkeeping requirements

40 CFR Part 94 Environmental protection, Admi nistrative practice and procedure, Air pollution control, Confidential business information, Imports, Incorporation by refere nce, Penalties, Reporting and recordkeeping requirement s, Vessels, Warranties.

Dated_____________

___________________________________ Stephen L. Johnson,
Administrator.