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Clean Air

Clear, smog-free skies like this are the goal of Environmental regulation.

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The Clean Air Acts of 1970, 1977 and 1990 gave EPA and state governments the authority to reduce the presence of six air pollutants to meet national health standards: lead, sulfur dioxide, carbon monoxide, nitrogen oxides, ozone (smog) and particulates.

These standards are updated periodically to keep up with the latest scientific research on the health effects of these pollutants. EPA recently tightened the standards on ozone, fine particulates and lead and is working with state partners and others to further reduce emissions.

Foreign-flagged ships steam into California ports, creating a major source of air pollution. To control this, EPA and other federal agencies have been working to implement MARPOL Annex VI-an international treaty to reduce maritime pollution.

At the local end of the spectrum, EPA has been working with community groups in neighborhoods and small cities to encourage involvement in local decisions that can have an impact on residents' exposure to pollution.

However, not all pollution is man-made. In California and Hawaii, wildfires and volcanic eruptions emit massive quantities of particulates and sulfur dioxide that are beyond human control. EPA has been working with state and local governments to better warn residents when conditions are hazardous in order to minimize health risks.

Tighter Standards Bring Healthier Air

After thorough reviews of the latest scientific research on the health effects of air pollutants, EPA tightened national air quality standards on fine particulate pollution in December 2006, ozone in March 2008, and lead in October 2008.

Adoption of the new standards has triggered a series of planning processes involving EPA, states, tribes and local air districts that will extend the progress toward healthier air seen in most areas since the 1970s.

Trends in Particulate Pollution

Since December 2006, EPA has tightened national air quality standards on fine particulate pollution, ozone and lead.

In 1997, EPA set standards for fine particulates, or PM2.5 (particulate matter of 2.5 microns or smaller), when scientific evidence showed them to be an even greater health threat than larger particles.

EPA has been tracking levels of fine particulate matter since 1999 and has seen improvement nationwide. In the Pacific Southwest, two areas did not meet the 1997 standards: California's San Joaquin Valley and South Coast. The state has since provided EPA with detailed plans on how these two areas would meet the standards by the required Clean Air Act deadline.

Map showing PM2.5 Nonattainment Areas

In December 2008, EPA designated areas that fail to meet the new PM2.5 standard. Larger version

In December 2006, EPA tightened the 24-hour PM2.5 standard from 65 to 35 micrograms per cubic meter. As a result, EPA in December 2008 designated areas that met or failed to attain the new standard (see map). In the Pacific Southwest, these nonattainment areas were located in California and Arizona. Both states are on track to provide EPA with implementation plans for attaining the new PM standard.

A federal appeals court has asked EPA to reevaluate the annual PM2.5 standard (for longer-term exposure), which the agency had left unchanged at 15 micrograms per cubic meter.

Refining the Ozone Standard

After scientific studies showed that the earlier standard for ozone was insufficient to protect public health, EPA in 1997 tightened the standard to 0.08 parts per million (effectively 0.084 ppm with rounding). The agency again revised the ozone standard in March 2008, tightening it to 0.075 ppm with no rounding.

State and tribal recommendations identifying areas that meet or fail to meet the new ozone standard were due to the agency by March 12, 2009. EPA expects to finalize designations in March 2010, after which states must submit plans showing how they will meet the new standard by the Clean Air Act deadline.

Tightening Limits on Lead

Scientific evidence about the health effects of lead (Pb) has grown dramatically since EPA set the initial standard in 1978. Studies have shown that exposure to very low lead levels can be harmful, especially to young children.

More on air quality:

Office of Air and Radiation

In October 2008, EPA tightened the standard from 1.5 down to 0.15 micrograms per cubic meter. Currently, EPA is improving the existing lead monitoring network by requiring monitors both in areas with industries that emit more than a ton of lead per year, as well as in urban areas with more than 500,000 people.


Community Involvement Helps Solve Local Problems

Traditionally, environmental protection has been a government-driven process. For example, to improve air quality, EPA adopts national health standards; states and regional air districts adopt plans and pollution control measures needed to attain the standards. Increasingly, another approach is also getting results-community involvement in government decision-making.

Decisions about planning, zoning and permits are made by all levels of government. These decisions often have an impact on local air, water and land quality. EPA is collaborating with local groups in some highly impacted communities to assist them in engaging on local environmental issues. The agency provides local groups grant resources and technical assistance to expand their opportunities to address environmental concerns.

Building Capacity and Reducing Exposures in the San Joaquin Valley
Arvin Community Meeting
EPA staff and local residents at a community meeting to discuss environmental hazards in Arvin, Calif.

Environmental hazards in Arvin include air pollution, a Superfund site, contaminated drinking water, and pesticide use.

The small city of Arvin, at the southern end of California's San Joaquin Valley, has multiple environmental challenges. First is unhealthy air-Arvin is downwind of most of the valley's air pollution sources. Every four days, on average, the ozone (smog) levels exceed the national health standard.

According to the San Joaquin Valley Unified Air District's plan for attaining the federal health standard for ozone, it will take Arvin longer to attain than just about anywhere else in the valley. Valley-wide decisions about planning, zoning, and permits can speed up the process or slow it down.

Other environmental hazards in Arvin include a Superfund site, other waste sites, arsenic-contaminated drinking water, and exposure to pesticides drifting from surrounding farms. Arvin is 88% Hispanic, has a 25% unemployment rate, and a median household income of only $23,000.

Perimeter of the Brown & Bryant Superfund site in Arvin, where groundwater cleanup is underway.

EPA is collaborating with the local Committee for a Better Arvin to build capacity, engage regulatory partners, and protect public health. Last year, the committee co-hosted two workshops with EPA, California's Cal/EPA, and others. These workshops informed nearly fifty participants about EPA programs, grant opportunities, and tools for the community to better understand toxic hazards. The committee secured a $20,000 EPA grant for environmental education and capacity building.

EPA is also helping the community address its other challenges. The agency's drinking water program conducted inspections and took enforcement actions for arsenic violations in five valley communities, including the Arvin Community Services District, which serves 16,000 people. The district is now installing additional water treatment facilities and, until they are built, notifying the public of unhealthful levels of arsenic in the water supply. The program also organized a community meeting to understand residents' concerns and inform them about how to spot future violations.

EPA's Superfund program held public meetings with Arvin city officials, the Committee for a Better Arvin, and the Arvin Community Services District to update everyone about groundwater cleanup work underway at the Brown and Bryant Superfund site. In addition, EPA inspected aboveground fuel storage tanks in response to community concerns, and informed the committee about how to identify violations and call in complaints.

Reducing Impacts of Goods Movement in Southern California

The ports are the source of 20% of diesel particulate emissions in Southern California.

The Ports of Long Beach and Los Angeles are the entry point of 40% of all imports to the U.S. and the source of 20% of diesel particulate emissions in Southern California. Air pollution associated with goods movement-including ships, diesel trucks and trains-causes an estimated 1,200 premature deaths in the South Coast Air Basin annually, with one-tenth of that attributed to the ports alone. Los Angeles County has a population of 10 million, with minorities making up nearly 70%.

Last year, EPA collaborated with minority and low-income communities in Southern California to focus enforcement efforts and to influence port expansion plans. First, to educate its staff, EPA hosted national Environmental Justice Goods Movement Workgroup member Prof. Andrea Hricko and Prof. Ed Avol, an air pollution health effects expert who serves on multiple port and goods movement committees. The two University of Southern California professors took part in a presentation and six staff meetings on health research, emission reduction strategies, and ways to improve both EPA and public participation.

As an outgrowth of that visit, EPA and the West Coast Diesel Collaborative cosponsored an environmental justice workshop in Southern California to publicize grant funding opportunities. Representatives of 20 local groups attended the workshop. Riverside's Center for Community Action and Environmental Justice secured an EPA grant to educate and organize residents to get involved in local decision-making to reduce particulate air pollution. Riverside County has millions of square feet of distribution centers that serve the Ports of L.A. and Long Beach.

EPA's enforcement programs prioritized inspections at industrial sites in Wilmington that posed potential environmental and public health threats. The agency also organized two Community Tools and Resources workshops, one in Riverside County and another in the ports area.

In commenting on five environmental impact statements for port-related projects, EPA recommended additional mitigation measures to offset significant and unavoidable impacts to neighboring communities. The agency also recommended a community health impact assessment, which would estimate the health effects of the air pollution and other potential health stressors added by the projects and would help identify appropriate mitigations.

In addition, EPA grants helped to replace more than 900 old, polluting trucks operating in and around the ports with new, clean-burning natural gas trucks, bringing cleaner air to neighboring communities (see related story).

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Protecting People from Natural Hazards: California's Wildfires, Hawaii's "Vog"

About 40% of all U.S. imported goods come ashore at the ports of Long Beach and Los Angeles and are moved inland by diesel trucks and trains.

Not all air pollution is man-made. In Northern California in June 2008, lightning ignited more than 2,000 wildfires. While most were extinguished within a few days, some of the largest continued for weeks, creating a pall of smoke that covered much of the state.

On the Big Island of Hawaii, residents contend with "vog," or volcanic smog: the sulfur dioxide (SO2) and sulfate particles from Kilauea Volcano. While these events are beyond human control, EPA works with state and local governments to reduce people's exposure to air pollution.

Tribal Request for Assistance in Fire Areas

In California, the stubbornest fires burned in rural Humboldt, Trinity and Siskiyou counties, including the lands of the Hoopa, Yurok and Karok Tribes. The three tribes requested assistance with air monitoring from state and federal agencies, including the California Air Resources Board (CARB) and EPA.

When the tribes also requested help with health messaging and issuing advisories to residents, EPA's Tim Wilhite worked with the Indian Health Service and the Hoopa Tribe on communications. But urban areas hundreds of miles away from the fires, like Sacramento, Fresno and the San Francisco Bay Area, were also affected by the smoke. Local officials and residents could see and smell the smoke for weeks, and wondered if breathing the air was hazardous.

Real-time air quality information:


More on natural hazards:

Natural Disasters and Weather Emergencies

More on vog:

Important Information about VOG Exiting EPA (disclaimer)

In response, EPA was able to share air quality data, along with links to public health information on how to minimize smoke exposure, via the AIRNow Web site. The AIRNow site also proved its value later in the year when the predictable spate of late-dry-season wildfires hit in Southern California-and continues to offer useful advice about minimizing exposure to air pollution.

Hawaii "Vog" Threatened Residents, Visitors

On March 19, 2008, there was an explosion at Halemaumau crater in Hawaii Volcanoes National Park-the first since 1924. Later, two more explosions opened vents that emitted up to 7,000 tons per day of SO2, more than quadruple the normal "background" level recorded in previous years. To protect nearby residents and park visitors, the state and county requested EPA assistance with air monitoring and forecasting unhealthy air conditions.

Air Quality in Hawaii on April 26, 2008

EPA's Janet Yocum helped state and county officials with air monitoring and data analysis during their initial emergency response. Catherine Brown, Susan Stone and Scott Jackson worked with the Hawaii Department of Health (DOH) to create a more permanent system for alerting the public to vog's health impacts. They helped DOH initiate real-time reporting for SO2 via the Hawaii DOH Web site and helped add reporting of fine particulates to EPA's AIRNow Web site. EPA is working with DOH and other agencies to develop next-day online forecasting as well.

The monitoring showed that people living near the park were sometimes exposed to unhealthy levels of SO2 and particulates. Data were translated into real-time air quality alerts (posted on the Hawaii DOH and AIRNow Web sites) showing where vog and fine particulate pollution reached unhealthy levels.

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Maggie Waldon: A Tenacious Approach to Air Enforcement

Cases against 10 polystyrene manufacturers have a major impact.

Having English Bulldogs has taught Maggie Waldon a thing or two when it comes to working in the Pacific Southwest Air Division's Enforcement Office. "Bulldogs never give up and neither do I," she says.

Maggie Waldon

Maggie Waldon

At five feet tall, Maggie doesn't appear threatening-but what she lacks in height she makes up for in determination. Since joining the Enforcement Office in 2001, Maggie has specialized in developing cases that require the stubbornness of a bulldog.

At first, it was easy enough focusing on companies that were illegally emitting hazardous air pollutants in their solvent degreasing operations and getting them to use non-toxic alternatives or air pollution controls. Then Maggie's focus began to turn to emissions of both hazardous air pollutants and volatile organic compounds, especially those being emitted by aerospace companies, refineries and manufacturers of polystyrene foam.

These companies were emitting volatile organic compounds (VOCs), air pollutants that were difficult to quantify because there were no proven measurement systems and existing analytical methods fell short. "The problem with VOCs is that they are invisible," says Maggie. "Once the polluting activity has ceased, it's hard to go back and prove that there were excess emissions." VOCs threaten public health because, in the presence of sunlight, they react with other pollutants to form the photochemical oxidant known as ozone (or smog).

"When we started doing inspections of polystyrene manufacturers five or six years ago, the industry was 'under the radar' of regulators," Maggie says. The facilities aren't large, but there are lots of them. They make the foam that's embedded in walls of new buildings for insulation, laid beneath newly-paved roads and runways (it's less brittle than cement), and the familiar packing "peanuts" and cheap foam coolers for picnics.

Estimating emissions from these facilities is more complicated than just putting an emissions monitor on a smokestack. VOCs can leak out of equipment, pipes and connections anywhere between the foam manufacturing process and the control device. At one facility, Maggie found that the VOCs weren't going to a control device at all. The facility's permit required the gases to go to a boiler, but instead they were being piped through a hole in the wall, directly into the air.

After Maggie initiated several enforcement actions against polystyrene manufacturers in the Pacific Southwest Region, other EPA regional offices began inspecting polystyrene manufacturers in their regions. Then the industry's trade association held a national meeting to discuss how to respond. Ultimately, Maggie initiated civil enforcement cases against 10 manufacturers. Some of these are already concluded, with facilities paying penalties ranging from $150,000 to $400,000 and installing state of the art control devices. Some are still in negotiations between EPA, the Department of Justice, and the manufacturers.

As part of a national enforcement team looking at oil refineries, Maggie helped negotiate a settlement with ConocoPhillips in which ConocoPhillips agreed to pay a penalty of $4.5 million and spend an additional $10 million on environmentally beneficial projects to reduce emissions further and to support activities in the communities where it operates. ConocoPhillips operates refineries in the Los Angeles area, San Luis Obispo, and the San Francisco Bay Area.

Maggie also supports regional emergency response operations as a member of the Response Support Corps and the Radiation Emergency Response Team.

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New Clean Air Technologies Emerge

Learn more:

West Coast Collaborative Exiting EPA (disclaimer)

Click here to download the EPA PDF announcing an interagency forum held in Merced, California in July 2008, 1 page, 110 kilobytes

Inset: Announcement (PDF) (1 pp, 110K, About PDF) for interagency forum held in Merced, Calif., in July 2008.

As usual, California is at the center of the action in the quest for cleaner technologies.

On July 9, 2008, at the California Emerging Clean Air Technology Forum in Merced, federal, state and local agencies joined forces to develop and implement technologies needed for California to meet federal air quality standards, to reduce people's exposure to air toxics, and to reduce greenhouse gas emissions. This year, the forum is continuing as an ongoing collaborative effort between EPA, the California Air Resources Board (CARB), the South Coast and San Joaquin Valley air districts, Cal/EPA, and the California Energy Commission.

These agencies signed a commitment to develop, test and deploy new sustainable technologies to accelerate progress in meeting national air quality standards. Experts from across the nation presented the latest research on hydraulic and plug-in hybrids, electric vehicles, fuel cells, air monitoring and remote sensing, agricultural water pump efficiency, and diesel mobile source controls, among others.

The Merced event focused on new and emerging technologies to reduce air pollution from both mobile and industrial sources. This group will determine which technologies to move forward and implement the research projects to help meet California's unique air quality challenges.

On January 5, 2009, EPA, CARB and the South Coast Air Quality Management District sponsored an event at the Puente Hills Landfill to showcase cleaner burning tractors, bulldozers and other earth moving equipment that is ahead of schedule in meeting the state's new, stringent diesel emissions standards. The new regulation requires the installation of diesel soot filters on off-road diesel engines and encourages the replacement of older, dirtier engines with newer emission-controlled models.

The largest grant recipient for diesel emission reduction activities, nonprofit Cascade Sierra Solutions, received $1.13 million from EPA in September 2008 in a first-of-its-kind grant to help lower the fuel costs of truckers and reduce greenhouse gas emissions and diesel pollution. An additional $17.1 million will be leveraged by the Cascade Sierra Solutions partners to provide below-market interest rate loans to truckers, allowing them to install idle reduction technologies on more than 1,700 trucks.

Under the program, truckers will save approximately $10 million in fuel costs per year, or over 2.5 million gallons of diesel fuel per year-and at the same time reduce 28,000 tons of carbon dioxide, 32 tons of particulate matter, and 630 tons of nitrogen oxides per year.

The Diesel Emissions Reduction Act
Former EPA Regional Administrator Wayne Nastri shows the difference in exhaust emissions between old diesel earth-movers and new ones that meet California 's new emissions standards.

Since 2004, EPA has issued grants for projects throughout the West Coast that save fuel while reducing diesel emissions. The Diesel Emissions Reduction Act of 2005 (DERA) provided additional funding to cut emissions from diesel engines nationwide. Since 2004, EPA issued grants totaling $32 million for 115 projects in the Pacific Southwest, affecting more than 7,463 on- and off-road engines.

Diesel engines emit nitrogen oxides, CO2 and soot, which are linked to thousands of premature deaths, hundreds of thousands of asthma attacks and millions of lost work days. These grant projects will have immediate and significant benefits for public health, and will help to advance new technologies and approaches for the future.

The American Recovery and Reinvestment Act of 2009 will provide more than $33 million to states and other eligible entities in the Pacific Southwest to support the implementation of diesel emission reduction technologies through DERA. Under this program, funding will be used to achieve significant reductions in diesel emissions while maximizing job preservation and creation.

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Crossing Borders

MARPOL Annex VI Treaty to Require Cleaner Ships

The U.N. International Maritime Organization set new, stringent standards limiting ships' emissions of smog-forming nitrogen oxides.

EPA has been instrumental in carrying out a newly-ratified treaty to prevent air pollution from ships: the MARPOL Annex VI Treaty.

This treaty sets up an international maritime program that consists of two sets of standards to control ships' emissions. The first sets a cap on the sulfur content of fuel, while the second limits nitrogen oxides emissions from ships' engines. The U.S. ratified the treaty in 2008.

Diesel engines on oceangoing vessels such as container ships, tankers, bulk carriers, and cruise ships are significant contributors to air pollution in many of our nation's cities and ports, especially ports in the Pacific Southwest Region, such as Los Angeles, Long Beach and Oakland. Controlling these emissions not just here but throughout the world will provide important air quality benefits to many millions of coastal and inland residents.

Most ships that come to the U.S. are flagged in other countries, but they're subject to international standards. State and local air quality regulators have long been frustrated by air pollution from ocean-going ships, since states and local governments for the most part can't regulate them under the Clean Air Act. As land-based emissions have come under tighter and tighter limits, especially in Southern California's South Coast Air Quality Management District, ship emissions from fast-growing port traffic has accounted for a growing portion of the smog and particulate pollution.

On October 9, 2008, the 168 member states of the United Nations' International Maritime Organization (IMO) adopted stringent new standards to control harmful exhaust emissions from the engines that power oceangoing vessels. This is a critical first step that may eventually help millions of Americans and many more people around the world to breathe cleaner air. To fully realize the significant benefits of this program, countries that have ratified the treaty can seek an emission control area (ECA) designation from the IMO.

More on oceangoing vessels:

Oceangoing Vessels

Since the U.S. ratified the treaty, EPA (the lead U.S. federal agency) has been working with the U.S. State Department, U.S. Coast Guard, and the Government of Canada to develop a comprehensive approach to establishing ECAs along all U.S. and Canadian coasts. EPA expects to submit the U.S./Canadian application for ECAs to the IMO in late March in preparation for consideration at its next regularly scheduled meetings in July 2009. Approval of the application could then take place as early as the IMO's March 2010 meeting.

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