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National Clean Diesel Campaign (NCDC)

Working Together for Cleaner Air

State & Local Toolkit - Design

Program Design

There are many options to consider when designing an effective diesel emission reduction program. Potential program ideas are presented here along with factors to consider when designing a program. Every jurisdiction is different, so use this information to design a program that works best for your specific circumstances.

Designing Financial Incentives, found in the Funding Section of this toolkit, describes and gives examples of common approaches used to encourage program participation.

You will need Adobe Reader to view some of the files on this page. See EPA's PDF page to learn more.

Strategic Approaches

Some states and regional groups have taken a systematic approach to diesel emission reductions by incorporating the interests of a variety of stakeholders, gathering and incorporating relevant data and information, targeting efforts, and creating an action plan for achieving environmental results.

California: California's Diesel Risk Reduction Plan Exit EPA Disclaimer
This plan outlines the need for diesel emissions reductions, as well as a regulatory approach for reducing particulate matter emissions from diesel sources.
California: San Pedro Bay Ports Clean Air Action Plan (CAAP) Exit EPA Disclaimer
The ports of Long Beach and Los Angeles adopted the landmark San Pedro Bay Ports Clean Air Action Plan (CAAP) to curb port-related air pollution from trucks, ships, locomotives, and other equipment by at least 45 percent.
Connecticut: Connecticut Diesel Mitigation Plan Exit EPA Disclaimer
This plan was developed to reduce fine particulate matter from diesel engines used in public transportation, school buses, and construction equipment. More on Connecticut's diesel reduction efforts can be found at the state's Diesel Reduction Initiatives. Exit EPA Disclaimer.
Various: Northwest Ports Clean Air Strategy Exit EPA Disclaimer
This plan is being drafted by the Port of Seattle, Port of Tacoma, and the Vancouver Port Authority to reduce maritime and port-related emissions that affect air quality and climate change in the Pacific Northwest.

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Regulatory and Mandatory Requirements

Section 209 of the Clean Air Act outlines the authorities and constraints for regulating emissions from new and in-use engines. Regulatory authorities differ for highway and nonroad engines, and California has unique authorities granted through an EPA waiver process.

A general discussion can be found in the Report from the Clean Air Act Advisory Committee (CAAAC) Recommendations for Reducing Emissions from the Legacy Diesel Fleet (PDF) (92 pp, 676KB). In general, with the exception of locomotive engines, states can usually adopt provisions relating to the use, operations, or movement of registered vehicles and engines within their borders.

Many states have combined diesel emissions reduction requirements with grant programs to help offset the cost of retrofitting vehicles and equipment. Commonly, requirements are focused on public projects, public fleets, school buses, and idle reduction measures.

Examples of Regulatory and Mandatory Requirements: Exit EPA Disclaimer
State Program Description
Nationwide SmartWay Transport's State and Local Idling Laws Provides a model for state idling laws and a list of state and local idle reduction laws.
California California's Diesel Risk Reduction Plan Outlines the need for diesel emissions reductions, as well as a regulatory approach for reducing particulate matter emissions from diesel sources. The California Air Resources Board's diesel activities include regulations and requirements for cleaner fuels and a broad array of mobile and stationary engines.
Connecticut Connecticut Clean School Bus Legislation (PDF) (1 pg, 10K) Requires school buses statewide to be retrofitted with advanced pollution control devices and authorizes financial assistance for retrofit reimbursement.
New York New York State's Diesel Emissions Reduction Law Requires the use of the best available control technology and ultra-low sulfur diesel (ULSD) in heavy-duty fleets owned and operated on behalf of the state.
New York New York City's Diesel-related Laws Include signed and proposed laws that reduce diesel emissions from nonroad vehicles (Local Law 77), city motor vehicles, sight-seeing buses, and school buses.
New Jersey Diesel Risk Reduction Law (PDF) (3 pp, 21K) Requires the retrofitting of more than 40,000 publicly owned or contracted diesel vehicles. A portion of the state's corporate business tax reimburses fleet owners for the cost of the retrofits. New Jersey's Stop the Soot provides information and resources about the program.
Rhode Island Rhode Island Diesel Emissions Reduction Act Requires the retrofit of older school buses by September 2010, and targets the retrofitting of waste collection and recycling vehicles.

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Environmental Management Systems

Governmental entities can encourage greener operations by promoting and participating in Environmental Management Systems (EMS) or other notable environmental certifications, such as the ISO 14001:2004.

An EMS is a set of processes and practices that enable an organization to reduce its environmental impacts and increase its operating efficiency.

EMS efforts have resulted in significant diesel emission reductions. For example, Grace Pacific Corporation’s EMS efforts led the corporation to partner with the American Lung Association to reduce diesel emissions in its quarry and asphalt operations.

The Port of Houston Authority’s EMS sets targets for nitrogen oxides (NOx) and volatile organic compounds (VOCs) that were achieved through engine replacements and cleaner fuels. The Port Authority estimates NOx reductions of more than 25 percent and VOC reductions of more than 32 percent at its Barbours Cut Container Terminal.

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Contract Provisions

Some public and private entities have placed provisions in construction contracts to encourage or require the use of clean diesel strategies. Contract provisions can take many forms including contract specifications, preferences, and allowances. While more commonly used to promote diesel emission reductions in the construction sector, landlord port authorities can also use air quality language in port leases with tenants.

Clean Construction USA’s Air Quality Language (PDF) (11 pp, 101KB) contains numerous examples of contracting procedures and air quality language.

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Public Recognition

Governments can encourage diesel emission reductions by recognizing and rewarding organizations that participate in formalized certification or recognition programs.

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Emissions Inventory and Emission Reduction Quantification

There are a number of methodologies and models available to measure mobile source emissions and calculate the present and future impacts on air quality. Refer to the toolkit's Emissions Inventory for a list of available models.

There are also models available for quantifying emission reductions and estimating the cost effectiveness of different strategies.

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Retrofit technologies can be installed on existing vehicles or equipment to reduce PM, NOx, CO, or HC. EPA and the California Air Resources Board (CARB) verify the emissions performance of retrofit technologies through appropriate protocols and statistical analysis. Verified products undergo rigorous testing to confirm the technology's emissions performance.

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