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Clean Air

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

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Clean air is a simple concept, but keeping it clean is not so simple. The tremendous diversity of topography and weather in the Pacific Southwest dictates that air will nearly always be healthy in some places, but not in others. It’s a long way from the breezy Hawaiian islands to the sun-baked valleys of California.

But the biggest factor is the human one. Of all the things we do, energy use is the biggest determinant of how clean the air will be and which pollutants will be a problem. In California, a large percentage of the air pollution results from burning fuel for transportation—cars, trucks, buses, ships and trains. In Nevada and Arizona, with smaller populations and fewer vehicles, a greater proportion comes from fossil-fuel-burning electric power plants.

Global climate change has added a new dimension to air concerns—greenhouse gases, such as carbon dioxide and methane. But in the end, the key to both ensuring healthy air and reducing greenhouse gases is tackling the energy issue.

In 2007, EPA’s regional office was active on several fronts: taking enforcement actions against fossil-fuel power plants that exceeded permitted emissions limits, holding a scientific conference on the air quality impacts of anticipated climate change, unveiling a bus and package delivery truck powered by innovative drive systems, and putting together a strategy to coordinate energy-related activities.

Clean Air

New Tools Allow Web Users to Map Air Quality Information

The quality of the air we breathe varies day to day. In the past, finding out if poor air quality was a hazard to one’s health meant waiting for a weather forecaster on TV or radio to announce it. Detailed information was hard to get, and air quality often wasn’t mentioned until it became hazardous for everyone, leaving sensitive populations like asthmatics gasping for breath.

Local air-evaluations are available at websites like Google.com or EPA.gov

The dots on this map represent air quality at monitoring stations—green is good, yellow is moderate, orange is unhealthy for sensitive groups.

Real-time data can help parents decide if it’s safe for their children with asthma to play outside.

Since then, air quality has improved dramatically in most urban areas, and so has the availability of accurate air quality data. EPA made a major advance a few years ago with the AIRNow Web site, making air quality data available online. Last November, AIRNow data became even more useful when EPA released a dynamic data layer on Google Earth, allowing anyone to combine detailed mapping with air quality information that’s updated hourly.

This combining of different types of data—often referred to as a “mashup”—gives the user a distinct new look at information. In this case, EPA’s Air Quality Index (AQI), based on real-time monitoring data, is merged with the cartographic imagery of Google Earth. This information can benefit everyone, particularly people with asthma, the elderly, and other sensitive populations who can use accurate pollution conditions to make daily decisions about their activity levels or exposure to outdoor air.

For instance, parents of a child with asthma can decide if it’s safe to allow their child to play soccer. TV weather forecasters can combine the AQI layer with other information they display to viewers. Individual users can also decide which data to combine based on their own needs: Home buyers could “mash up” the AQI with real estate listings to inform their decision-making. Community activists may choose to overlay the AQI on a map showing the location of industrial facilities.

During air quality emergencies like wildfires, where smoke conditions can change quickly, the AQI layer can be crucial for early response teams or fire departments. By using AQI on Google Earth, they can see where the pollution is worst and overlay other information such as the locations of schools, hospitals, airports and roads. Being able to layer such crucial information can help inform decision makers.

The AQI is a color-coded numeric system that rates air quality according to six divisions that express conditions: 0-50 is healthy, 51-100 moderate, 101 to 150 unhealthy for sensitive groups, 151-200 unhealthy, 201 to 300 very unhealthy, and 301-500 hazardous.

With this information visually displayed on Google Earth, it’s easy to assess local air quality conditions wherever you happen to be—and to customize the experience with an intuitive mapping tool. Just visit AIRNow.gov and select "AQI in Google Earth" under Resources.

For air quality conditions and projections

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Energy and Climate Change

More on Reducing Energy
Use and Emissions

EPA is working with state, local and nongovernment partners across the Pacific Southwest to tackle issues involving energy use and its impact on our climate.

This report describes several of these efforts, from local measures to new technology development to advances in global science.

Air Quality Impacts of Climate Change

New Hybrid Technologies for Trucks, Buses

Reducing Power Plant Emissions in Nevada

Steve Frey: Enforcing the Clean Air Act

Cleaner Cleanups Reduce Local, Global Impacts

Grants, Challenges Spur Green Building

California Surpasses 50% Waste Diversion Goal

East Bay MUD Creates Energy from Food Waste

The national dialogue on climate change reached a new level in 2007 as scientists, policy makers, leaders of industry and individuals focused on the latest findings of climate researchers and weighed the most effective approaches to mitigation.

Assessing the Problem
Windmills like these can provide renewable power.

Wind power is one of California’s renewable energy sources.

Throughout the year, the United Nations Intergovernmental Panel on Climate Change (IPCC) issued a series of reports that raised awareness and concern about climate science, environmental impacts, and mitigation options. The IPCC stated that “Warming of the climate system is unequivocal, as is now evident from observations of increases in global average air and ocean temperatures, widespread melting of snow and ice, and rising global average sea level.”

In its findings, the panel noted that it is very likely (>90% probability) that human influence has caused warming over the past 50 years. The IPCC also said that if greenhouse gas emissions are left unchecked, global temperatures would likely increase between 2.0 and 11.5° F, potentially causing greater sea level rise and extreme weather, impacting human health, ecosystems, and food and water availability.

In the Pacific Southwest, the State of California has also assessed potential impacts from climate change. California found that medium warming assumptions, in drier scenarios, caused the Sierra Nevada spring snowpack to be reduced by 80%. With those same assumptions, there would be a 55% increase in wildfire frequency, and 75 to 85% more days when ozone (smog) could form in Los Angeles and San Joaquin Valley.

The Role of Energy

The energy we use to power our homes, businesses and transportation system is the source of nearly 90% of the greenhouse gas emissions in the U.S. Increasing the efficiency of the energy we burn, reducing emissions from traditional energy sources, and aggressively seeking new sources of energy that put less carbon into the atmosphere are all important strategies in reducing greenhouse gas emissions.

In prioritizing opportunities to reduce emissions, it is important to understand their source. In California, the transportation sector has received particular focus because it accounts for a larger share of greenhouse gas emissions than in the U.S. as a whole—39% vs. 28%—accounting for more of California’s greenhouse gas inventory than the electric power industry.

Evaluating Needs, Taking Action
Coal-fired power plants like this one in Page, Arizona contribute to climate change through their carbon emissions.

The coal-fired Navajo Generating Station near Page, Ariz.

At the national level, EPA has begun evaluating options for regulating greenhouse gases following the U.S. Supreme Court’s ruling that the agency has authority to do so under the Clean Air Act. Late in the year, the President signed H.R. 6, the Energy Independence and Security Act of 2007, which increases renewable fuel mandates, sets more aggressive vehicle fuel efficiency standards, and promotes investment in energy efficiency.

In the Pacific Southwest, EPA’s office in San Francisco is working with the region’s state, tribal and local governments as they take an active role in evaluating their needs related to climate change.

With its large population and powerful economy, California’s total greenhouse gas emissions dwarf those of its neighbors (as shown in Fig. 1). However, the state has long been a national leader in addressing emissions and energy efficiency, with by far the lowest per-capita greenhouse gas emissions of states in the region.

California’s extensive energy and climate change polices and regulations include AB32 (the Global Warming Solutions Act of 2006), SB1368 (Global Warming Emissions Standard for Electricity Generation) and the Low Carbon Fuel Standard. The Governor’s office is directing implementation of the state’s Climate Action Plan. The state has completed extensive analyses of energy and climate change issues, with projections and recommendations detailed in a Climate Action Team Report to the Governor and Legislature, and the state Energy Commission’s Integrated Energy Policy Report.

Arizona has developed a Climate Change Action Plan that includes a greenhouse gas inventory and recommendations for various energy-related sectors. Hawaii is completing an update to their Energy Strategy, last completed in 2000. In 2007, the state adopted legislation similar to California’s AB32.

Nevada in 2007 adopted legislation requiring greenhouse gas emissions inventories and a Climate Change Advisory Committee. The state recently completed an Energy Status Report and a Renewable Energy and Energy Efficiency Report for the Governor and Legislature.

At the regional level, EPA’s Pacific Southwest Regional Office is working to improve coordination of its own activities related to energy and climate change (the list to the right provides a small sampling). Evaluating opportunities across all environmental programs—from waste management to air quality to water infrastructure—will also facilitate increased support of other federal, state, local and industry efforts.

An example of regional leadership has been EPA’s convening of the West Coast Diesel Collaborative, which has brought a concentrated focus to the issue of goods movement—from ships to the huge network of trains and trucks that move goods from ports to store shelves. EPA has brought together regional officials from across the U.S. to discuss solutions for port-related pollution. These efforts, together with EPA’s core role in setting national emissions standards, will continue to ensure progress in improving public health in these areas.

Primer: Greenhouse Gas Emissions Chart v4

Figure 1: California Greenhouse Gas Emissions (in Million Metric Tons CO2 Equivalents)
Notes to Figure 1: 1. 2004 emissions, 2. 2000 emissions, 3. 2005 emissions,
4. 2005 preliminary estimate

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Conference Addresses Impacts of Climate Change on Air Quality

In October 2007, some of the nation’s leading climate change scientists gathered with EPA, state, local and tribal air quality regulators for a conference in San Francisco to address the predicted impacts of climate change on air quality. The scientists shared the results of their current research and participated in discussions with regulators on integrating science with policy and on priorities for future research.

EPA sponsors conferences, like this one on Climate Change.
Stanford University's Dr. Stephen Schneider is one of the world's foremost experts on climate change science.

Among the distinguished speakers was Stanford University’s Dr. Stephen Schneider, who shared the 2007 Nobel Peace Prize with fellow members of the United Nations Intergovernmental Panel on Climate Change and former Vice President Al Gore.

The conference was organized by EPA’s Pacific Southwest Air Division, in conjunction with EPA’s national Office of Research and Development (ORD), which leads EPA’s efforts to conduct, fund and communicate climate change research.

Studies cited at the conference indicated that rising temperatures associated with climate change will produce a “climate penalty” of worsening ozone (smog) levels. Areas that now barely attain federal ozone standards could become non-attainment areas, and existing non-attainment areas will need more time and pollution controls to meet the standard. If nothing is done to further strengthen pollution controls, rising smog levels will result in increased mortality among the elderly, sick, or frail, one scientist predicted.

Studies on the impact of climate change on particulate pollution indicated varying results, depending on the chemical composition of the particles. Smoke particles will become an increasing problem if rising temperatures cause more and bigger wildfires. Scientists and air quality regulators agreed on the need for more research on how climate change affects particulates.

Government air quality managers called for more information to help them understand the benefits and trade-offs of energy and climate change policy, as well as the prospects for carbon sequestration and cleaner coal combustion. One climate change mitigation strategy—energy efficiency—was predicted to provide triple benefits: cleaner air, better health, and cost savings.

Some of the state, local and tribal air quality managers voiced their interest in further collaborating with EPA on climate change and using EPA’s climate modeling tools and research. EPA’s Office of Research and Development plans to publish in 2008 a synthesis of results from EPA-funded research on the impacts of climate change on air quality.

The October workshop generated a list of future research themes and collaboration opportunities to help guide upcoming activities. For example, EPA’s regional office is organizing a series of meetings with local scientists working on air quality and climate change issues. In addition, the regional office will participate in helping ORD set future research priorities on adapting to the impacts of climate change on air quality.


EPA’s Global Change Research Program

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New Hybrid Technologies
Bring Cleaner Trucks and Buses

Hybrid-drive vehicles like this conserve resources & protect the air.

California's first plug-in electric hybrid school bus is now in use in the Napa Valley.

Diesel trucks and buses more than 10 years old are the dirtiest vehicles still on the streets. Since they generally last 20 years, they won’t disappear overnight. But when they do, they may be replaced by fleets of trucks and buses far cleaner and more energy-efficient, thanks to new hybrid technology developed by EPA and several partner organizations. In fact, these new drive systems may also be used in light trucks, SUVs and vans.

In August 2007, EPA joined the Bay Area Air Quality Management District, Pacific Gas & Electric Co., and Advanced Energy officials to award a total of $215,843 in grants to the Napa Valley Unified School District to fund California’s first plug-in electric hybrid school bus. The bus has the potential to double fuel efficiency and reduce emissions by up to 90%.

Meanwhile, EPA’s laboratory in Ann Arbor, Michigan, has patented an innovative hydraulic hybrid drive system for delivery trucks that’s now being road-tested. The demonstration model, a 12-ton UPS delivery vehicle, stopped in at the South Coast Air Quality Management District offices in Diamond Bar, Calif., in December 2007. In lab tests, the truck slashed fuel use by an amazing 60 to 70%, and reduced smog-forming hydrocarbon emissions by 50% and particulate emissions by 60%, compared to conventional trucks.

Hybrid-drive vehicles like this conserve resources & protect the air.

EPA developed the energy-saving hydraulic hybrid drive system now being road-tested in this delivery truck.

Trucks that operate in urban stop-and-go traffic—such as delivery vehicles—contribute significantly to pollution and fuel consumption. “If every truck adopted this technology, it would make a big difference for air quality,” said Matt Haber, deputy director of EPA’s regional Air Division.

The hydraulic hybrid drive system costs more to build, but would pay for itself within three years by cutting fuel costs, ultimately saving $50,000 over a truck’s 20-year lifespan, based on a fuel price of $2.75 per gallon. As fuel prices continue to increase, lifetime savings would be even greater.

The unique UPS delivery vehicle features EPA-patented hydraulic hybrid technology. It uses hydraulic pumps and hydraulic storage tanks to store energy that is normally lost in braking. When the vehicle accelerates, it uses that energy. The engine is also more efficient and can shut off when stopped or decelerating.

The truck was designed with the support of UPS, Eaton Corporation-Fluid Power, International Truck and Engine Corporation, the U.S. Army, Morgan-Olson, the University of Wisconsin, the University of Michigan, and Michigan State University. FEV Engine Technology Inc., and Southwest Research Institute built the vehicle under contract to EPA.

More info and video on this new technology

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Reducing Emissions
from Las Vegas Power Plants

It takes lots of energy to power the glittering lights and laboring air conditioners of Las Vegas’ famous “Strip,” as well as the city’s fast-growing suburbs in Clark County, Nevada. Most residents never see the fossil-fuel-burning power plants that supply most of the area’s electricity, but they’ll soon breathe cleaner air thanks to two legal settlements with local utility Nevada Power that will sharply reduce smokestack emissions.

Sprawl in Las Vegas causes smog.

Las Vegas and its suburbs continue to
grow rapidly.

In the first case, the Nevada Department of Environmental Protection (NDEP) spent two years investigating alleged Clean Air Act violations at Nevada Power’s Reid-Gardner coal-fired generating plant 50 miles northeast of Las Vegas. The NDEP carefully assembled evidence, then issued 56 violation notices to Nevada Power for exceeding limits on particulate matter emissions at the facility. Some of the violations included faulty record-keeping, which made it difficult to measure the extent of the illegal emissions.

Nevada Power and NDEP called for EPA’s assistance to help resolve the case. After two years of negotiating, EPA, NDEP and the company reached a settlement with multiple benefits. First, Nevada Power agreed to spend $85 million on pollution control equipment to reduce the plant’s particulate emissions by more than 300 tons per year, and reduce nitrogen oxide (NOx) emissions by at least 282 tons per year. The company also agreed to set up an Environmental Management System to ensure that future compliance will be verified.

Secondly, the company agreed to fund more than $4 million in energy conservation projects for the Clark

This coal-fired power plant in Nevada received 56 citations for air pollution over 2006-2007.

Nevada Power’s coal-fired Reid-Gardner Generating Station. Photo: Nevada DEP

County School District over the next seven years, saving the schools at least $500,000 per year in energy costs, as well as reducing air pollution by cutting fuel consumption. And finally, the company agreed to pay $1.11 million in penalties to the state and federal governments.

The other case involved Nevada Power’s natural gas-burning Clark Generating Station. While natural gas is cleaner than coal, older gas-fired plants emit far more NOx than newer ones using the Best Available Control Technology (BACT). That’s why the Clean Air Act’s New Source Review rule requires BACT whenever fuel-burning power plants are substantially modified.

EPA found that the company had made major changes at Clark that increased NOx emissions without installing the required pollution controls. In the settlement, the company agreed to reduce the plant’s NOx emissions by about 2,300 tons per year, a dramatic 86% reduction, at a cost of about $60 million. The company also agreed to fund a $400,000 photovoltaic solar power array on the roof of a building housing a local nonprofit organization. In addition, Nevada Power will pay a $300,000 penalty.

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Steve Frey:
Enforcing the Clean Air Act

Steve Frey helps enforce the Clean Air Act using many tools -including the telephone!

Steve Frey

When Steve Frey talks about his 32-year career at EPA as an environmental engineer involved in Clean Air Act enforcement, what’s striking are the large numbers: Thanks to cases Steve worked on, the coal-fired Navajo Generating Station reduced its sulfur dioxide (SO2) emissions by 65,000 tons per year in the 1990s. The Four Corners Power Plant, another coal-burner on the Navajo Nation, more recently slashed its SO2 emissions by 88% for a 20,000 ton-per-year reduction. Nevada gold mines reduced mercury emissions by more than 16,000 pounds per year.

Of course, Steve didn’t do it alone. At the Four Corners Power Plant, the reductions were the result of a partnership between the Navajo Nation, the Arizona Public Service Corp., the National Park Service, Environmental Defense, Western Resource Advocates, and New Mexico Citizens for Clean Air and Water. Nevertheless, as an expert in monitoring air pollutants and testing pollution control equipment, his role was crucial to ensuring that the agreed-upon reductions were achievable, and provable.

Steve grew up in the Philadelphia area, and began studying chemical engineering at Pennsylvania State University in the early 1970s. After the Energy Crisis of 1973-74, he switched his focus to air pollution control engineering, and after graduation took a job with EPA’s regional office in New York City. He traveled throughout the state of New York inspecting power plants, chemical plants, cement plants, and other pollution sources. He also helped the state write permits for such facilities, providing the technical expertise needed to ensure they minimize emissions.

Always an avid skier, Steve was drawn to the West by the skiing. The best powder snow, he says, is in the Rockies, so in 1980 he moved to EPA’s office in Denver. There, he tested smoke-control devices on wood-burning stoves to help develop Colorado’s wood stove pollution standards. Steve was also heavily involved in a federal court case aimed at two plants in Colorado making waferboard—wood panels manufactured using wood chips and glue. These plants were part of a new industry that had underestimated their emissions and built without major new source construction permits required by the Clean Air Act.

Inspecting facilities and enforcing permits help reduce air pollution by tens of thousands of tons each year.

Steve transferred to EPA’s regional office in San Francisco in 1988, where he was assigned to Clean Air Act enforcement. Here, one of his early cases involved another wood products industry case which was concluded as part of a national settlement involving the two major waferboard companies in the U.S. for more than 20 of their plants that they built without the proper permits. Ultimately, EPA required all such facilities to install pollution control equipment to limit emissions of smog-forming volatile organic compounds (VOCs).

For the past decade, Steve has worked on enforcement cases involving some of the Pacific Southwest’s biggest coal-burning power plants—thus the big numbers. In some of these instances, like the Four Corners Power Plant, EPA works with the owner and other stakeholders to negotiate voluntary but binding agreements for pollution reductions, which can take effect faster than traditional enforcement actions, which may involve protracted litigation.

One recent negotiation with the Arizona Public Service Co., regarding the coal-burning Cholla Power Plant east of Flagstaff, produced an agreement in which the company is spending $300 million on equipment to reduce SO2 emissions by more than 70%, particulate emissions by 50%, and smog-forming nitrogen oxides (NOx) by 40%.

Steve is planning to retire in 2008, but his work will be carried on by his colleagues in the regional Air Division’s enforcement office, under the leadership of office chief Doug McDaniel.

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