Clean Diesel Legislation

One of the most serious current threats to public health from air pollution comes from the burning of diesel fuel. The burning of diesel produces ultra-fine particulate matter, or PM2.5 (particulate matter less than 2.5 microns). This diesel particulate matter is small enough that it can penetrate deep into the lungs and even cross over into the blood stream. Long-term exposure to diesel emissions is linked to both lung and bladder cancer.  Children are particularly vulnerable to the impacts of diesel pollution because their lungs are still developing and they breathe, on average, 50 percent more air per pound of body weight than do adults.

To date, the State of Oregon has failed to take adequate action on protecting the health of Oregonians from diesel particulates. However, in 2017, there is a huge opportunity for our state legislature take action on drastically reducing exposure to dirty diesel emissions.

The Cost of Dirty Diesel

In a recently released report called “Dirt on Diesel 2016: The True Cost to Oregon of Delaying Action“, the Oregon Environmental Council describes the many negative and avoidable effects of dirty diesel pollution to Oregon, which:

  • causes more fatalities than traffic crashes;
  • puts 90% of Oregonians at excess risk for cancer;
  • damages the heart, lungs, and brain;
  • causes up to 460 premature death in Oregon each year;
  • costs up to $3.5 billion a year in health costs and lost productivity; and
  • is at highest concentrations in neighborhoods with more low-income and people of color.

Though this issue affects 90% of Oregonians, some areas in the state are disproportionately impacted by diesel emissions. Modeling by the Oregon Department of Environmental Quality (DEQ) shows the extent of the diesel particulate problem in the Portland Metro Area.

Exposure to Diesel Particulates in the Portland Metro Area - retrieved from Linda George's presentation to the Oregon Diesel Workgroup, available at:

Exposure to Diesel Particulates in the Portland Metro Area – retrieved from Dr. Linda George’s presentation to the Oregon Diesel Workgroup, available at:

Diesel pollution also acts a short term climate change accelerator because it contains black carbon, a particle that is the second most important individual climate forcing agent behind carbon dioxide. According to the EPA, black carbon influences climate by (1) directly absorbing energy from the sun and converting it to thermal energy that warms the air, (2) reducing the reflectivity of snow and ice through deposition (“the Albedo Effect”), and (3) interacting with clouds. The particles emitted by mobile diesel engines are about 75% black carbon.

These costs to Oregonians are entirely avoidable. Through the installation of filters, other control devices and using ultra-low sulfur diesel fuel, diesel particulate can be reduced by 90-99%. The technology currently exists to reduce diesel in-use emissions by up to 85% and capture up to 95 percent of particulate matter through clean diesel particle filters. In addition, new clean diesel trucks and buses emit 99 percent less black carbon than those manufactured before 2004. It is the job of our state officials to make sure that this technology is utilized in Oregon.

Oregon’s Regulatory History with Diesel

Since 2001, the State of Oregon has engaged in efforts to promote clean diesel and reduce the harms associated with diesel exhaust. In 2007, the Oregon legislature passed HB 2072 and HB 3201 which collectively allowed for grants, loans, and tax credits for clean diesel repowers, retrofits, and truck engine scrapping with the goal of reducing excess lifetime cancer risk from diesel exhaust exposure in Oregon to no more than one in a million by 2017. Soon after, this mandate was implemented in Oregon’s administrative rules by the Environmental Quality Commission. Through the Oregon Clean Diesel Initiative, the Department of Environmental Quality administered millions of dollars worth of tax credits, federal grants, and general funds toward retrofitting and repowering dirty diesel engines. In 2011, the retrofit and repower tax credit program ended and budget reductions resulted in positions being cut. DEQ continues to administer grants within its funding limitations, but the State of Oregon has not funded diesel engine upgrades since 2009, missed a state goal to upgrade all diesel school buses by 2017, and has allowed 23 or 36 Oregon counties to exceed the state health benchmark for diesel pollution.

When compared with other states’ efforts in reducing exposure to diesel particulate, including Washington and California, Oregon’s efforts to curtail diesel pollution are underfunded and lack adequate regulation to phase out dirty diesel engines. From 2002-2015, Washington invested $58 million in 14,00 diesel engine upgrades while Oregon invested $4.3 million in 369 diesel engine upgrades. In California, forward thinking diesel policy and adequate funding means that all trucks and buses will run 95% cleaner by 2023. Our neighbors’ successes shows that it is only due of a lack of political will that Oregon will not meet its goal of reducing excess cancer risk from diesel exhaust exposure to no more than one in a million by 2017. However, we have an opportunity in the 2017 legislative session to correct course to phase out dirty diesel at much faster pace and protect the health of millions of Oregonians.

Opportunities for State Action on Diesel

In 2015, Senator Michael Dembrow introduced clean diesel legislation (SB 824), which evolved into the clean diesel workgroup. The workgroup, which includes Neighbors for Clean Air, has been charged with studying technical information about diesel engines and emissions, the health impacts of diesel particulate, the potential for state regulation of diesel, and mechanisms for funding state diesel regulation. As a result of this workgroup, Senator Michael Dembrow is expected to propose diesel legislation again in 2017 and you can express support by contacting Senator Dembrow and your state representatives.

In the Summer of 2016, the State of Oregon settled an emissions fraud lawsuit against Volkswagen for $85 million; $68 million of which will be dedicated toward reducing diesel emissions in Oregon. Though certainly not enough to fix the problem, this money will provide a much needed shot in the arm to the Oregon Clean Diesel Initiative.

With strong diesel legislation, a fully funded clean diesel incentive program, and political will, we can be on the way to protecting Oregonians from the health and climate impacts of dirty diesel emissions.