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Puget Sound Clean Air Agency Diesel Solutions - Case Study

Photo of buildings near Puget Sound

The Puget Sound Clean Air Agency, along with a consortium of partners, has developed the Diesel Solutions Program to make diesel vehicles in this region dramatically cleaner. This voluntary initiative will leverage the introduction of ultra-low sulfur diesel fuel into western Washington and enable a wide range of public and private fleets to join a consortium to retrofit diesel vehicles. This is a model program with experience that can be transferred to other urban areas of the country.

Heavy duty trucks and buses run on diesel fuel. Diesel fuel emits one-third of all nitrogen oxide (NOX) and a quarter of all particulate matter emissions from mobile sources. These pollutants contribute to many health problems in the U.S., including, but not limited to, asthma and lung cancer. In 2001, the U.S. EPA proposed the "Heavy-Duty Engines and Vehicle Standards and Highway Diesel Sulfur Control Requirements." This rule established a single, comprehensive national control program to regulate heavy-duty vehicles and the diesel fuel they use as a single system. The ultimate goal of this rule is to reduce NOX emissions by 90% by reducing the sulfur content in diesel fuel by 97%, resulting in reductions in the annual emissions of NOX, nonmethane hydrocarbons, and particulate matter by 2.6 million, 115,000, and 109,000 tons respectively by 2030. In 2006, ultra-low sulfur diesel fuel will become the only on-road diesel fuel available in most areas of the country. In 2007, new cleaner engines that require the ultra-low sulfur diesel fuel will become the only new engines sold. However, given the long life and durability of diesel engines it would be 2020 before most of the diesel vehicles on the road would be cleaner, less polluting models. This deadline was not soon enough for Puget Sound, an environmentally sensitive region with approximately 86,000 diesel vehicles. As a result, the Puget Sound Clean Air Agency created the Diesel Solutions Program, a fleet program that targets approximately 37,000 vehicles. Diesel Solutions has brought the benefits of cleaner diesel engines and ultra-low sulfur diesel fuel sooner to the metro-Seattle area.

A strong driver for the program locally was the release of National Air Transportation Association (NATA) information that placed the Puget Sound region in the top 5 percentile of communities nationally for air toxics exposure. The NATA release was followed by local air monitoring and an air toxics assessment that verified the NATA modeling and showed approximately 70% of air toxics risk in the region was related to diesel exhaust emissions.

After hearing several national presentations by the U.S. EPA, national oil refiners, and retrofit device manufacturers, the director of the Puget Sound Clean Air Agency Director approached local refiners and asked if they had the capability to produce ultra-low sulfur diesel earlier than EPA rules required. Several said they might be able to do so if a sufficient commitment to purchase the fuel could be confirmed. The Agency Director then approached the Mayor of Seattle, the King County Executive, and the Boeing Company to see if they would participate in a pilot project. They all indicated they would if the price for fuel was low enough and if there was some grant money to offset some of the costs. This led to the Diesel Solutions Program, a collaborative effort between the Puget Sound Clean Air Agency, U.S. EPA, Seattle fleet managers, engine manufacturers, refiners, and retrofit equipment manufacturers. This program's goal is to make diesel vehicles in the Central Puget Sound area in western Washington dramatically cleaner now rather than waiting for regulations that will come into effect in 2006 and 2007. Program participants have voluntarily begun to retrofit their diesel vehicles with emission reduction devices, at a cost of $1,500 to $7,500 per vehicle, and to use ultra-low sulfur fuels for cleaner air emissions. Ultra-low sulfur diesel fuel is being supplied by Conoco Philips and U.S. Oil five years before the EPA is requiring the fuel be made available, making this initiative possible and more effective.

More than sixty private and public organizations and businesses have partnered on Diesel Solutions. Metro/ King County, the City of Seattle, Boeing, Emerald City Disposal, the Everett School District, the Community Transit, Kitsap Transit, the Chief Leschi School District of the Puyallup Tribe, the North Kitsap School District, and Sound Transit have all begun installing oxidation catalyst and particulate filter retrofit devices and phasing in the use of ultra-low sulfur fuels for their transit and diesel vehicle fleets. Other partners, such as the Washington State Department of Transportation Ferry Division and the Port of Seattle, will begin retrofitting and switching fuels in the next one to five years. The Agency is expanding its program to begin work on construction equipment retrofits and cleaner fuels by developing incentives and construction specifications for local projects requiring cleaner fuels and equipment. The Agency has current commitments for over 1,300 particulate filter installations and several thousand oxidation catalyst retrofits.

Positive Results

To date, about 3,000 (of the total 37,000 targeted) retrofits have been installed on diesel vehicles in the region. Over two-thirds of the retrofits have been oxidation catalysts and approximately 40 million gallons of ultra low sulfur diesel fuel are being used annually by fleet operators. There are commitments for many more particulate filters and oxidation catalysts with funding in place to insure they occur. The program has had many positive results including the following: provided the impetus for legislation that is funding the retrofitting of all the diesel school buses in the state (over 8,000 buses); stimulated two other retrofit projects in the state; provided another way for private point sources to mitigate the emissions from their projects, i.e., retrofit diesel buses in their own or publicly owned fleets; provided a concrete example of how to mitigate the impacts from construction activity on highway projects; and enticed a second refinery to begin producing ultra-low sulfur diesel fuel early.

Fine particle (soot) and toxic emissions from retrofit vehicles have decreased by as much as 90 percent thus far. Hydrocarbon emissions have been lowered to nearly undetectable levels. Environmental results will be achieved five years prior to the implementation of this new regulation and 15 years prior to the full effectiveness of them, based on typical fleet turnover. Data also are maintained by each fleet operator/partner.

Key Elements, Suggestions, and Challenges

Strong leadership by the director of the Air Agency and strong commitment to participate from the political leaders and chief executive officers (CEOs) of the partners have been major resources in creating the program and doing specific projects. Strong participation from the fleet managers of the partners is critical for successful installation of the retrofit devices and use of the ultra-low sulfur diesel fuel. Oil refiners require a significant market commitment to make the tankage and supply commitments necessary to start a program. The supply of ultra-low sulfur diesel fuel and the demand for the fuel must be established at the same time. Technical assistance and education, particularly at the fleet manager level, have been crucial to gaining acceptance of the program concept of retrofitting diesel engines, using ultra-low sulfur fuel, and successfully retrofitting vehicles.

The EPA Office of Transportation and Air Quality (OTAQ) provided up to $1 million dollars during several years to support this project. This funding has been the key resource in getting people to undertake specific retrofit projects. For each dollar spent by EPA, the retrofitting localities and transit agencies are spending ten dollars. Without this financial commitment on the part of EPA, there would not have been any commitments or incentive to proceed with such an extensive project. Other funding partners include the Puget Sound Clean Air Agency and Washington State Department of Ecology and settlements funds from Cummins Engine Company and Detroit Diesel. Other ingredients to facilitate success include: sharing common goals and needs and cooperating among the various stakeholders; participating facilities that are economically viable and willing; and the regulatory community that recognizes and rewards the participants.

At various times, the commitments to fund the project became precarious. The Puget Sound region has experienced a prolonged and deep recession with high tech industry and aerospace manufacturing being very hard hit. Despite the deep recession and very significant public budget deficits, the program has continued to receive funding commitments. When one of the original partners had to delay ultra-low sulfur fuel purchases for budgetary reasons, the refinery partner continued to produce the fuel at a lower volume than originally anticipated. The Puget Sound Clean Air Agency has also had to work through a variety of minor, yet challenging, issues such as fuel filter plugging, cooler exhaust temperatures on some vehicles than initially profiled, higher costs for retrofit equipment than originally anticipated, and lower funding support from grants than originally anticipated. Project managers would like to see a broader scope of participation, but more outreach is needed. Retrofit costs and fluctuating gas prices for fleet owners are somewhat daunting, but with the assistance of Federal funds and local government technical assistance, these burdens are being mitigated.

More Information
http://www.pscleanair.org : Puget Sound Clean Air

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