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Canada-United States Air Quality Agreement Progress Report 2012

Section 1: Commitments

Acid Rain Annex


The Acid Rain Annex to the 1991 Air Quality Agreement established commitments for both countries to reduce emissions of SO2 and NOX, the primary precursors to acid rain. The commitments also include prevention of air quality deterioration, visibility protection, and continuous emission monitoring. Both countries have succeeded in reducing the impact of acid rain on each side of the border. Studies in each country, however, indicate that further efforts are still necessary to restore damaged ecosystems to their pre-acidified conditions.

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Key Commitments and Progress: SO2Emission Reductions


For more than two decades, Canada has steadily reduced SO2 emissions, through various actions including the requirements to reduce sulfur content in fuels and the implementation of the Canada-wide Acid Rain Strategy for Post-2000. The Strategy serves as the framework for addressing the issues related to acid rain with the goal that the deposition of acidifying pollutants does not further deteriorate the environment in eastern Canada and that new acid rain problems do not occur elsewhere in Canada. In 2010, Canada’s total SO2emissions were 1.4 million metric tons (1.5 million short tons), or about 57 percent below the national cap of 3.2 million metric tons (3.5 million short tons).[1] This also represents a 57 percent reduction from Canada’s total SO2emissions in 1990 (see Figure 1).

The largest contribution of SO2 emissions comes from industrial sources, which accounted for about 65 percent of national SO2 emissions in 2010. Key sources such as the non-ferrous smelting and refining industry and the upstream petroleum industry contributed 27 percent and 20 percent, respectively, to national SO2 emissions in 2010. Electric power generation accounted for 24 percent of the national total. The majority of overall reductions in national SO2 emission levels can be attributed to the SO2 emission reductions undertaken by the four eastern provinces (New Brunswick, Nova Scotia, Quebec, and Ontario) targeted by the Acid Rain Strategy and recent facility closures.

While Canada has been successful in reducing emissions of acidifying pollutants, many areas across Canada have a low capacity to withstand acid deposition and continue to receive levels in excess of critical loads, most notably in eastern Canada. A critical load is the maximum amount of acidifying deposition an ecosystem can tolerate in the long term without being damaged. (See the ecological effects chapter in Section 2 later in this report for more information.)

Additional measures to reduce SO2 and NOXemissions from certain industrial sectors are being considered as part of the new air quality management system for Canada (see Section 3: New Actions on Acid Rain, Ozone, and Particulate Matter).

Figure 1. Total Canadian Emissions of SO2, 1980–2010

Total Canadian Emissions of SO2, 1980–2010

Source: Environment Canada, 2012


United States

The United States succeeded in meeting its commitment to reduce annual SO2 emissions by 10 million short tons (9.1 million metric tons) from 1980 levels by 2000. Additionally, since 2007, emissions of SO2 from the electric power sector have been below the 2010 national emission cap of 8.95 million short tons (8.1 million metric tons).

The Acid Rain Program (ARP), established under Title IV of the 1990 Clean Air Act (CAA) Amendments, requires major emission reductions of SO2 and NOX, the primary precursors of acid rain, from the power sector. The SO2program sets a permanent cap on the total amount of SO2that may be emitted by electric generating units (EGUs) in the contiguous United States and uses a market-based cap and trade program to achieve emission reductions. The program was phased in, with the final 2010 SO2 cap set at 8.95 million short tons (8.1 million metric tons), a level of about one-half of the emissions from the power sector in 1980. NOX reductions under the ARP are achieved through a program that applies to a subset of coal-fired EGUs and is closer to a traditional, rate-based regulatory system.

In 2011, the SO2 requirements under the ARP applied to 3,640 fossil fuel-fired combustion units that served large generators greater than 25 megawatts (MW) at 1,245 facilities across the country providing electricity for sale. ARP units emitted 4.5 million short tons (4.1 million metric tons) of SO2 in 2011, meaning that ARP sources reduced emissions by 11.2 million short tons (10.2 million metric tons, or 71 percent) from 1990 levels and 12.8 million short tons (11.6 million metric tons, or 73 percent) from 1980 levels. The vast majority of ARP SO2 emissions result from coal-fired EGUs, although the program also applies to oil and gas units.

These reductions occurred while electricity demand (measured as heat input) remained relatively stable, indicating that the reduction in emissions was not driven by decreased electric generation. Instead, there was a drop in emission rate. A drop in emission rate represents an overall increase in the environmental efficiency of these sources as power generators install controls, run controls year round, switch to different fuels, or otherwise cut their SO2 emissions while meeting relatively steady demand for power.

Clean Air Interstate Rule

In 2005, the U.S. promulgated the Clean Air Interstate Rule (CAIR) to address regional interstate transport of ozone and fine particle (PM2.5) pollution. CAIR requires 24 eastern states and the District of Columbia (D.C.) to limit annual emissions of NOX and SO2, which contribute to the formation of PM2.5 (particulate matter less than or equal to 2.5 microns). CAIR also requires 25 states and D.C. to limit ozone season NOX emissions, which contribute to the formation of smog during the summer ozone season (May to September).

However, in July 2008, the U.S. Court of Appeals for the D.C. Circuit granted several petitions for review of CAIR, finding significant flaws in the rule. Subsequently, in December 2008, the court issued a ruling to keep CAIR and the CAIR Federal Implementation Plans (FIPs) -- including the CAIR trading programs -- in place temporarily until the U.S. Environmental Protection Agency (EPA) issued new rules to replace CAIRand the CAIR FIPs.On July 6, 2011, EPA finalized the Cross-State Air Pollution Rule (CSAPR) to replace CAIR. On December 30, 2011, the court stayed CSAPR pending judicial review and on August 21, 2012, the court issued an opinion vacating CSAPR. In its August opinion, the court also ordered EPA to continue administering CAIR.

CAIR includes three separate cap and trade programs to achieve the rule’s required reductions:  the CAIRNOX ozone season trading program, the CAIRNOX annual trading program, and the CAIRSO2 annual trading program. The CAIRNOX ozone season and annual programs began in 2009, while the CAIR SO2 annual program began in 2010.  

In 2011, there were 3,345 affected EGUs at 951 facilities in the CAIR SO2 and NOX annual programs. The CAIR programs cover a range of unit types, including units that operate year round to provide baseload power to the electric grid as well as units that provide power on peak demand days only and may not operate at all during some years. Annual SO2 emissions from sources in the CAIR SO2 program alone fell from 9 million short tons (8.2 million metric tons) in 2005 when CAIRwas promulgated to 3.9 million short tons (3.5 million metric tons) in 2011, a 57 percent reduction. Between 2010 and 2011, SO2emissions fell 543,000 short tons (493,600 metric tons), or twelve percent. However, the 2011 emissions total is higher than the CAIR SO2 program’s state budget total of 3.6 million short tons (3.3 million metric tons), indicating that affected sources used banked allowances carried over from the ARP for compliance with CAIR.

U.S. EPA’s Quarterly Emissions Tracking site contains the most up-to-date emission and control data for sources in the ARP and CAIR (

In addition to the electric power generation sector, emission reductions from other sources not affected by the ARPor CAIR, including industrial and commercial boilers and the metals and refining industries, and the use of cleaner fuels in residential and commercial burners, have contributed to an overall reduction in annual SO2 emissions. National SO2 emissions from all sources have fallen from nearly 26 million short tons (23.6 million metric tons) in 1980 to just over 8 million short tons (7.3 million metric tons) in 2011 (see

Figure 2, below, combines emission and compliance data for both the ARP and CAIR to more holistically show reductions in power sector emissions of SO2 from these national and regional programs, as of 2011. 

Figure 2. SO2 Emissions from CAIR SO2Annual Program and ARP Sources, 1990–2011

SO2 Emissions from <abbr>CAIR</abbr> SO2 Annual Program and <abbr>ARP</abbr> Sources, 1990–2011

Source: U.S. EPA, 2012

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Key Commitments and Progress: NOxEmission Reductions


Canada has met its commitment to reduce NOX emissions from power plants, major combustion sources, and metal smelting operations by 100,000 metric tons (110,000 short tons) below the forecasted level of 970,000 metric tons (1.1 million short tons). This commitment is based on a 1985 forecast of 2005 NOXemissions. In 2010, industrial emissions of NOX totaled 632,093 metric tons (695,302 short tons). Emissions of NOX from all industrial sources and including emissions from electric power generation totaled 841,007 metric tons (925,108 short tons) in 2010, well below the forecasted level of 970,000 metric tons (1.1 million metric tons).

Transportation sources contribute the majority of NOXemissions, accounting for over 55 percent of total Canadian emissions, with the remainder produced by the upstream petroleum industry (21 percent), electric power generation facilities (10 percent), and other sources (see Figure 25). Canada continues to develop programs to further reduce NOX emissions nationwide. Additional information on Canadian emissions can be found at:

United States

The United States has exceeded its goal under the Acid Rain Annex to reduce total annual NOX emissions by 2 million short tons (1.8 million metric tons) below projected annual emission levels for 2000 without the ARP (8.1 million short tons, or 7.4 million metric tons).

Title IV of the CAA requires NOX emission reductions from certain coal-fired EGUs. Unlike the market-based NOX programs in CAIR, the ARP requires NOXemission reductions for older, larger coal-fired EGUs by limiting their NOXemission rate (expressed in lb/mmBtu). In 2011, 930 units at 375 facilities were subject to the ARP NOXprogram.

Emissions of NOX from all sources covered by the ARP were 1.9 million short tons (1.7 million metric tons) (Figure 3) in 2011. This level is over 6 million short tons (5.5 million metric tons) less than the projected NOX level in 2000 without the ARP, and over three times the Title IV NOXemission reduction commitment under the Acid Rain Annex.

While the ARP is responsible for a large portion of these annual NOX reductions, other programs--such as the CAIR NOX ozone season and annual programs, and state NOX emission control programs--also contributed significantly to the NOX reductions that sources achieved in 2011.

Figure 3. U.S. Title IV Utility Unit Annual NOX Emissions from All ARP Sources, 1990–2011

U.S. Title IV Utility Unit NOX Emissions from All ARP Sources, 1990–2011

Source: U.S. EPA, 2012

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Emissions/Compliance Monitoring


Canada has met its commitments to estimate emissions of NOX and SO2 from new electric utility units and existing electricity units greater than 25 MW using a method comparable in effectiveness to continuous emission monitoring systems (CEMS) and to investigate the feasibility of using CEMS by 1995. Continuous emission monitoring installation in Canada’s electric utility sector has been widespread since the late 1990s. By 2011, almost all new and existing base-loaded fossil steam plants with high emission rates have been operating CEMS. Coal-fired facilities, which are the largest source of emissions from the sector, have SO2 and NOX CEMS installed at more than 93 percent of their total capacity. Under Canada’s National Pollutant Release Inventory (NPRI) mandatory reporting program, electric power generating facilities are required to report their air pollutant emissions annually.

United States

The ARP requires affected units to measure, record, and report SO2 and carbon dioxide (CO2) mass emissions and NOX emission rates using CEMSor an approved alternative measurement method. The vast majority of emissions are monitored with CEMS, while the alternatives provide a cost-effective means of monitoring mass emissions for smaller and/or cleaner units. Table 1 shows the amount of SO2 emissions monitoring using CEMS.

Affected sources are required to meet stringent quality assurance and control requirements and report hourly emission data in quarterly electronic reports to the U.S. EPA. In 2011, the average percent of monitoring data available (a measure of monitoring systems’ reliability) was 99 percent for coal-fired units. This number is based on reported monitor data availability for SO2 monitors (98.9 percent), NOX monitors (99.2 percent), and flow monitors (99 percent).

Using automated software audits, the U.S. EPA rigorously checks the completeness, quality, and integrity of monitoring data. The Agency promptly sends results from the audits to the source and requires correction of critical errors. In addition to electronic audits, the U.S. EPA conducts targeted field audits on sources that report suspect data. In 2011, source compliance with ARP emission monitoring requirements was 100 percent for the 3,640 covered units. All emission data are available to the public within two months of being reported to U.S. EPA. Data can be accessed on the Air Markets Program Data website at

Table 1 shows the amount of SO2 emissions monitoring using continuous emission monitoring systems (CEMS) for primary fuels such as coal, gas, oil and other (which includes primarily wood, waste or other non-fossil fuel) in 2011. Affected sources are required to meet stringent quality assurance and control requirements and report hourly emission data in quarterly electronic reports to U.S. EPA.

Table 1. Units and SO2 Emissions Covered by Monitoring Method for the Acid Rain Program (ARP), 2011
Primary FuelCEM or Non-CEMUnits ReportingSO2 Mass (short tons)SO2 Mass (metric tons)Percentage of UnitsPercentage of SO2 Emissions

Note: “Other” fuel units include units that in 2011 combusted primarily wood, waste or other non-fossil fuel. (The total number of units in the table excludes 23 affected units that did not operate in 2011.)

Source: U.S. EPA, 2012

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Acid Deposition Monitoring, Modeling, Maps, and Trends

Airborne pollutants are deposited on the Earth’s surface by three processes: (1) wet deposition (rain and snow), (2) dry deposition (particles and gases), and (3) deposition by cloud water and fog. Wet deposition is comparatively easy to measure using precipitation monitors, and the concentration of sulfate and nitrate in precipitation is regularly used to assess the changing atmosphere as it responds to decreasing or increasing sulfur and nitrogen emissions. In Canada, to facilitate this comparison, measurements of wet sulfate deposition are typically corrected to omit the contribution of sea salt sulfate at near-ocean sites (less than 62 miles, or 100 kilometers [km], from the coast).

Figure 4 through Figure 6 show the United States–Canada spatial patterns of wet sulfate (sea salt-corrected) deposition for 1990, 2000, and 2010 (the most recent data year). Figure 7 through Figure 9 show the patterns of wet nitrate deposition for the same three years. Deposition contours are not shown in western and northern Canada because Canadian experts judged that the locations of the contour lines were unacceptably uncertain due to the paucity of measurement sites in all of the western provinces and northern territories. To compensate for the lack of contours, wet deposition values in western Canada are shown as colored circles at the locations of the federal/provincial/territorial measurement sites.

Figure 4. 1990 Annual Wet Sulfate Deposition

1990 Annual Wet Sulfate Deposition

Source: National Atmospheric Chemistry (NAtChem) Database ( and the National Atmospheric Deposition Program (NADP) (, 2010

Figure 5. 2000 Annual Wet Sulfate Deposition

2000 Annual Wet Sulfate Deposition

Source: NAtChem Database ( and the NADP (, 2010

Figure 6. 2010 Annual Wet Sulfate Deposition

2010 Annual Wet Sulfate Deposition

Source: NAtChem Database ( and the NADP (, 2012

The three maps indicate that wet sulfate deposition is consistently highest in eastern North America around the lower Great Lakes, with a gradient following a southwest-to-northeast axis running from the confluence of the Mississippi and Ohio rivers through the lower Great Lakes. The patterns for 1990, 2000, and 2010 illustrate that significant reductions occurred in wet sulfate deposition in both the eastern United States and eastern Canada.

By 2000, the region receiving greater than 28 kg/ha/yr (kilograms per hectare per year) of wet sulfate deposition had decreased to a small area near the southern shore of Lake Erie. By 2010, all regions in eastern Canada and the eastern U.S. were receiving less than 15 kg/ha/yr of wet sulfate deposition. The wet sulfate deposition reductions are considered to be directly related to decreases in SO2 emissions in both the United States and Canada. The emission reductions are outlined in “Key Commitments and Progress: SO2 Emission Reductions” in Section 1 of this report.

The patterns of wet nitrate deposition (Figure 7 through Figure 9) show a similar southwest-to-northeast axis, but the area of highest nitrate deposition is north of the region with the highest sulfate deposition. Reductions in wet nitrate deposition have generally been more modest than for wet sulfate deposition, except during the period from 2000 to 2010, when large NOXemission reductions occurred in the United States and, to a lesser degree, in Canada. As a result, by 2010, all regions were receiving less than 14 kg/ha/yr of wet nitrate deposition.

Figure 7. 1990 Annual Wet Nitrate Deposition

1990 Annual Wet Nitrate Deposition

Source: NAtChem Database ( and the NADP (, 2010

Figure 8. 2000 Annual Wet Nitrate Deposition

2000 Annual Wet Nitrate Deposition

Source: NAtChem Database ( and the NADP (, 2010

Figure 9. 2010 Annual Wet Nitrate Deposition

2010 Annual Wet Nitrate Deposition

Source: NAtChem Database ( and the NADP (, 2012

Wet deposition measurements in Canada are made by the federal Canadian Air and Precipitation Monitoring Network (CAPMoN) and networks in a number of provinces/territories, including Alberta, the Northwest Territories, Quebec, New Brunswick, and Nova Scotia. Dry deposition estimates are made at a subset of CAPMoN sites using an inferential method whereby air concentration measurements are combined with modeled dry deposition velocities. In the United States, wet deposition measurements are made by two coordinated networks: the National Atmospheric Deposition Program (NADP) / National Trends Network (NTN), which is a collaboration of federal, state, and nongovernmental organizations (, and the NADP/Atmospheric Integrated Research Monitoring Network (AIRMoN), which is a sub-network of NADP funded by the National Oceanic and Atmospheric Administration (NOAA) ( Dry deposition estimates in the United States are made using the inferential technique based on modeled dry deposition velocities and ambient air concentration data collected by the Clean Air Status and Trends Network (CASTNET) (, which is coordinated by the U.S. EPA and the National Park Service (NPS).

The measurements of wet deposition and air concentrations provided by the Canadian and U.S. networks have been shown to be reasonably comparable through collocated studies and inter-laboratory comparisons. In contrast to these measurements, the estimated dry deposition velocities from the Canadian (Big Leaf Model) and US (Multi-Layer Model) models are poorly correlated due to differences in resistance assumptions. Therefore, deposition fluxes at the collocated sites, calculated from the measured concentrations and modeled deposition velocities, are significantly different. As dry deposition is an important contributor to total deposition, ongoing efforts are in place to study the sources of these differences. At the Borden research station in Ontario, instruments were collocated for a number of years as part of a bilateral intercomparison study on modeling dry deposition. Recent studies[2] attempt to quantify the sensitivity of the CAPMoN and CASTNET dry deposition models to a variety of factors that influence dry deposition velocities, with the goal of refining model parameters for better comparability in future measurements, reconciling past measurements, and identifying further intercomparison needs. Data are available from the websites of the individual networks.

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Preventing Air Quality Deterioration and Protecting Visibility


Canada is addressing the commitment to prevent air quality deterioration and ensure visibility protection by implementing the Canadian Environmental Assessment Act, the Canadian Environmental Protection Act, 1999 (CEPA 1999), and the continuous improvement (CI) and keeping clean areas clean (KCAC) principles that are part of the Canada-wide Standards (CWS) for PM and Ozone.

Federal and provincial environmental assessment regulation requires that air quality be considered for all major new point sources or modifications to existing sources to ensure that Canadian objectives to protect the environment and human health are met. Mandatory provincial reporting processes require new and existing sources to file notifications, which are reviewed to determine the scale of the environmental assessment appropriate to each case. CEPA 1999 prefers to use pollution prevention in its approach to environmental protection. Implementing similar principles--pollution prevention, CI, and KCAC--is also part of the CWS.

The province of British Columbia continues to make progress towards implementing a visibility management program through the efforts of the British Columbia Visibility Coordinating Committee (BCVCC), an interagency committee consisting of representatives from different levels of government involved in air quality management in the province.

Following a 2010 workshop, the BCVCC adopted a visibility protection framework that describes the visibility management actions required to attain the BCVCC vision of “achieving clean air and pristine visibility for the health and enjoyment of present and future generations”. In 2011, Metro Vancouver adopted its new Integrated Air Quality and Greenhouse Gas (GHG) Management Plan, which includes the goal to “improve visual air quality”. This goal will be accomplished by reducing emissions of visibility degrading pollutants such as PM and by developing a visual air quality management program. As part of a pilot project to develop this program for the Lower Fraser Valley (LFV), the BCVCC is working in four main areas: (1) visibility science, (2) development of a visibility index, (3) development of a business case to quantify the benefits of improved visibility, and (4) communications and outreach.

Recent visibility science work includes upgrading the visibility monitoring network in the LFV, attribution of visibility impairment to emission sources, and the design of emission reduction scenarios for assessment by visibility modeling. The development of a visibility index based on human perception is nearly complete. The current index design is based on a recent perception survey carried out by the BCVCC as well as earlier survey work completed in the 1990s. Following testing, the index may be used as one of the metrics for a visibility improvement goal. The business case developed by the BCVCC outlines in dollar terms the various benefits of improving visibility in the LFV. Considerations in the business case include the health benefits of lower PM levels associated with better visibility, the results of a local study that indicated residents’ willingness to pay for better visibility and visibility impacts on tourism, the film industry, and real estate valuation. Communication and outreach efforts have resulted in the development of a visibility website for British Columbia ( as a means to promote visibility and educate the public on this issue.

In addition to the visibility protection efforts underway in British Columbia, additional activities have been undertaken in other parts of Canada as part of Environment Canada’s National Visibility Monitoring Pilot Study. In 2011, a visibility monitoring pilot site was established at Barrier Lake, Alberta, located on the eastern edge of the Rocky Mountains, close to Banff National Park. The site is operated by Environment Canada using the U.S. Interagency Monitoring of Protected Visual Environments (IMPROVE) protocol and includes both aerosol and optical measurements. This relatively pristine site provides background visibility measurements in a highly scenic part of Canada and is also well positioned to capture any transboundary impacts of air pollution on visibility. The IMPROVEprotocol allows for the integration of data from this new site into the U.S. IMPROVE database and the extension of the IMPROVE visual range map into Canada for a direct transboundary comparison. An additional pilot site was established in Wolfville, Nova Scotia, in 2011. This site includes optical and camera measurements, allowing for an assessment of visibility conditions in the scenic Annapolis Valley region. Ongoing work involves the inter-comparison of IMPROVE sampler data with the CAPMoN speciation samplers at Environment Canada’s research station in Egbert, Ontario, to ensure data comparability. In 2012 to 2013, a National Air Pollutant Surveillance (NAPS) speciation sampler will be collocated with an IMPROVE sampler at the Barrier Lake site in Alberta to assess comparability. Lastly, an updated assessment of visibility conditions across Canada using data from the NAPS speciation network is planned for 2012 to 2013.

United States

The United States has various programs to ensure that air quality is not significantly degraded by the addition of air pollutants from new or modified major sources. The CAA requires major new stationary sources of air pollution and extensive modifications to major existing stationary sources to obtain preconstruction permits. The permitting process is called New Source Review (NSR) and applies both to areas that meet the National Ambient Air Quality Standards (NAAQS) (attainment areas) and areas that exceed the NAAQS (nonattainment areas). Permits for sources in attainment areas are prevention of significant deterioration (PSD) permits, while permits for sources located in nonattainment areas are nonattainment area permits. PSD permits require air pollution controls that represent the best available control technology (BACT). BACT is an emission limitation based on the maximum degree of reduction of each pollutant subject to regulation under the CAA. BACT is determined on a case-by-case basis and considers energy, environmental, and economic impacts. Nonattainment area permits require the lowest achievable emission rate (LAER). BACT and LAERmust be at least as strict as any existing New Source Performance Standards (NSPS) for sources. One important difference between NSR permits and the NSPS program is that NSR is applied on a source-specific basis, whereas the NSPS program applies to all sources nationwide. The PSD program also protects the air quality and visibility in Class I areas (i.e., national parks exceeding 6,000 acres and wilderness areas exceeding 5,000 acres). The federal land management agencies are responsible for protecting air quality-related values, such as visibility, in Class I areas by reviewing and commenting on construction permits.

The CAA established the goal of improving visibility in the nation’s 156 Class I areas and returning these areas to natural visibility conditions (visibility that existed before human-caused air pollution). The 1999 Regional Haze Rule requires that states reach that goal by 2064 and specifies the State Implementation Plan (SIP) provisions that states must develop toward that goal. In July 2005, the U.S. EPA finalized amendments to the Regional Haze Rule. These amendments require the installation of emission controls, known as best available retrofit technology (BART), on certain older, existing combustion sources within a group of 26 source categories, including certain EGUs that cause or contribute to visibility impairment in Class I areas. Many of these older sources have never been regulated, and applying BART will help improve visibility in Class I areas. The BART requirements are to be operational no later than five years after the SIP is approved. In addition to BART, the rule also requires states to assess progress toward visibility improvement that could be made by controlling other non-BART emission sources. This is referred to as "reasonable progress". Decisions regarding potential emission controls for BART and reasonable progress are informed through an assessment of factors including cost effectiveness and the degree of visibility improvement expected.

The first planning period establishes an assessment of expected visibility conditions in 2018. The SIPs must be submitted every 10 years, and states revise their visibility goals accordingly to ensure that reasonable progress is being made to achieve natural visibility conditions by 2064. There is also a reporting check every five years, in which states report their interim progress toward reaching the goals. Additional information on the U.S. EPA’s Regional Haze Program can be found at

Figure 10 shows the annual average standard visual range within the United States for the period 2006 to 2010. “Standard visual range” is defined as the farthest distance a large dark object can be seen during daylight hours. This distance is calculated using fine and coarse particle data from the IMPROVEnetwork. Increased particle pollution reduces the visual range. The visual range under naturally occurring conditions without human-caused pollution in the United States is typically 45 to 90 miles (75 to 140 km) in the east and 120 to 180 miles (200 to 300 km) in the west. Additional information on the IMPROVEprogram and visibility in U.S. National Parks can be found at

Figure 10. Annual Average Standard Visual Range in the Contiguous United States, 2006–2010

Figure 10. Annual Average Standard Visual Range in the Contiguous United States, 2006–2010

Source: U.S. NPS, 2012 (data from IMPROVE website:

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Consultation and Notification Concerning Significant Transboundary Air Pollution

Joint Efforts

The United States and Canada initiated notification procedures in 1994, to identify potential new sources and modifications to existing sources of transboundary air pollution within 100 kilometers (62 miles) of the border. Additionally, the governments can provide notifications for new or existing sources outside of the 100 km region if they believe there is potential for transboundary air pollution. Since the publication of the last Progress Report in 2010, the United States has notified Canada of three additional sources for a total of 64 U.S. notifications. Canada has notified the United States of three additional sources, for a total of 58 Canadian notifications.

Transboundary notification information is available on the government websites of each country at the United States and Canada.

Following guidelines approved by the Air Quality Committee in 1998 for a consultation request by a Party on transboundary pollution concerns, the United States and Canada report ongoing progress on joint discussions concerning Essar Steel Algoma, Inc. (ESAI) in Sault Ste. Marie, Ontario.

Essar Steel Algoma, Inc.

The ESAI is an integrated primary steel producer located on the St. Mary’s River in Sault Ste. Marie, Ontario, approximately one mile from the United States–Canada border. The United States–Canada Algoma informal consultation group was formed in 1998 to address concerns regarding local cross-border pollution. Representatives from the United States and Canada hold regular discussions to coordinate monitoring programs in the Sault Ste. Marie area and to address progress in abating potential transboundary air pollution from the ESAI facility in Ontario. Air quality monitoring on the Canadian side has been ongoing since the 1960s, and the monitoring on the U.S. side was initiated by the Inter-tribal Council of Michigan in 2001. Sampling of fine PM and toxic air contaminants continues on both sides of the border.

Canadian and U.S. representatives have continued to meet to discuss progress toward reducing emissions from ESAIand to share results of air monitoring studies. To date, the air measurements recorded at the Michigan sites do not violate U.S. ambient air quality standards, nor do they exceed air toxics levels of concern for long-term exposure. However, several pollutants, including total suspended particulates and coarse PM (i.e., PM less than or equal to 10 microns, or PM10), exceed Ontario air quality criteria in the west end of Sault Ste. Marie, Ontario. The U.S. 24-hour NAAQS standard for PM2.5 was significantly reduced in 2006, but no Michigan sites exceeded the new standard.

In 2007, the Inter-tribal Council of Michigan installed a camera, facing toward Sault Ste. Marie, Ontario, as part of the Midwest Hazecam Network (see The Inter-tribal Council provided the Ontario Ministry of the Environment (MOE) with photographs documenting red and black particle plumes emanating from ESAI on multiple dates from 2007 to 2009. Ontario MOE staff have documented these emission events in their reporting system and contacted ESAI regarding previously unreported incidents.

ESAI completed installation of a permanent baghouse for the #7 blast furnace in February 2009. Due to the economic downturn, the #6 blast furnace is presently idle and ESAI does not have any plans to start the #6 blast furnace in the near future. When it does restart the #6 blast furnace, ESAI will have 10 months to have the permanent baghouse operating. ESAI initiated the operation of its cogeneration facility in 2009. The cogeneration facility is fully operational and produces approximately 70MW of electricity with the potential to generate up to 120MW if the #6 blast furnace is operating.

Also, ESAI has been ordered to conduct a modeling and monitoring study of the coke ovens, which will result in refined emission estimates for the coking operations. This study has been completed and is currently being reviewed by the company prior to release. ESAI has installed individual oven pressure controls on the #9 battery. This retrofit was the first of its kind in North America and was installed and operational on November 15, 2011. The company has commenced a second modeling and monitoring study as of May 1, 2012 to determine the effectiveness of the new controls in reducing fugitive emissions from the #9 battery. The #7 battery was retrofitted with a mechanized door and jam cleaner, which was operational on July 31, 2012. The ESAI bilateral consultation group continues to monitor and report on this facility and is in the process of analyzing air quality monitoring data collected since pollution controls were installed at the facility.

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Ozone Annex


The Ozone Annex commits both the United States and Canada to address transboundary ground-level ozone by reducing emissions of NOX and VOCs, the precursors to ground-level ozone. The commitments apply to a defined region in both countries known as the Pollutant Emission Management Area (PEMA), which includes central and southern Ontario, southern Quebec, 18 U.S. states[3] and D.C. The states and provinces within the PEMA are the areas where emission reductions are most critical for reducing transboundary ozone. The Annex was added to the AQA in 2000.

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Key Commitments and Progress


Vehicles, Engines, and Fuels

New stringent NOX and VOC emission standards for vehicles, including cars, vans, light-duty trucks, off-road vehicles, small engines and diesel engines, as well as fuels.

Emissions from vehicles, off-road equipment, and fuels account for more than 70 percent of the NOX emissions and more than 30 percent of the VOC emissions in the Canadian PEMA region. Consistent with its Ozone Annex obligations, Canada has implemented a series of regulations to align Canadian emission standards for vehicles and engines with corresponding standards in the United States.

The On-Road Vehicle and Engine Emission Regulations were in effect as of January 1, 2004, and introduced more stringent national emission standards, aligned with U.S. federal standards, for new 2004 and later model year light-duty vehicles and trucks, heavy-duty vehicles, and motorcycles. These regulations were amended in 2006 to introduce new requirements for 2006 and later model year on-road motorcycles. The changes ensured that Canadian emission standards for on-road motorcycles remain aligned with more stringent standards adopted by the U.S. EPA. In addition, Canada has proposed amendments to the On-Road Vehicle and Engine Emission Regulations to require on-board diagnostic (OBD) systems for on-road heavy-duty engines such as trucks and buses. The amendments were published in the Canada Gazette, Part I on October 29, 2011.

The Off-Road Small Spark-Ignition Engine Emission Regulations were in effect as of January 1, 2005, and established emission standards, aligned with U.S. federal standards, for 2005 and later model year engines found in lawn and garden machines, light-duty industrial machines, and light-duty logging machines.

The Off-Road Compression-Ignition Engine Emission Regulations, in effect as of January 1, 2006, have introduced emission standards aligned with U.S. federal standards (Tier 2 and 3), for new 2006 and later model year diesel engines, such as those typically found in agricultural, construction, and forestry machines. In December 2011, the Regulations Amending the Off-Road Compression-Ignition Engine Emission Regulations were published, further reducing the emission of air pollutants in Canada by establishing more stringent Canadian off-road diesel emission standards. The regulations align Canadian emission standards with the U.S. Tier 4 standards. The new standards came into force on January 16, 2012.

The Marine Spark Ignition Engine Vessel and Off-Road Recreational Vehicle Emission Regulations have been in effect since April 5, 2011. These regulations include emission standards, aligned with U.S. federal standards, for outboard engines, personal watercraft, sterndrive and inboard engines, vessels powered by these engines, snowmobiles, off-road motorcycles, all-terrain vehicles (ATVs), and utility vehicles. Most of the standards applied beginning with the 2012 model year, while the emission standards for vessels will apply as of the 2015 model year.

Regulatory initiatives for fuels include: the Sulphur in Gasoline Regulations, which limit the level of sulfur in gasoline to 30 milligrams per kilogram (mg/kg) (equivalent to 30 parts per million [ppm]) as of 2005; and the Sulphur in Diesel Fuel Regulations, which reduce the level of sulfur in diesel fuel to 15 mg/kg (15 ppm) for on-road vehicles, as of 2006; and off-road vehicles, as of 2010. Diesel fuel for rail and marine engines was reduced to 500 mg/kg (500 ppm) as of 2007 and was further limited to 15 mg/kg (15 ppm) as of June 1, 2012. Since 1999, the Benzene in Gasoline Regulations have reduced benzene emissions from vehicles by limiting the benzene content in gasoline to 1.0 percent by volume.

The United States and Canada have agreed to work together under the United States–Canada Air Quality Agreement to reduce transportation emissions by:

  • Harmonizing national vehicle and engine standards for emissions of smog-forming pollutants;
  • Optimizing vehicle and engine emission testing activities, taking advantage of unique testing capabilities, and sharing emission test data where appropriate to facilitate regulatory administration activities in both countries; and
  • Sharing information and discussing strategies and approaches on GHG emission standards for motor vehicles.

Stationary Sources of NOX

Annual caps by 2007 of 39,000 metric tons of NOX (as nitrogen dioxide [NO2]) emissions from fossil fuel power plants in the PEMA in central and southern Ontario, and 5,000 metric tons of NOX in the PEMA in southern Quebec.

In the Canadian portion of the PEMA, the largest source of NOX emissions from industry is the fossil fuel-fired power sector. Canada has met its commitment to cap NOXemissions from large fossil fuel-fired power plants in the Ontario and Quebec portions of the PEMA at 39 ,000 metric tons (42,900 short tons) and 5 ,000 metric tons (5,500 short tons), respectively, by 2007. Emissions from power plants in the Ontario portion of the PEMA were approximately 78,000 metric tons (86,000 short tons) in 1990. In 2011, NOX emissions from Ontario fossil fuel-fired power plants are estimated to be 10,600 metric tons (11,700 short tons), or 73 percent below the 39,000 metric tons (42,900 short ton) Ozone Annex commitment. Annual NOX emissions for 2010 from Quebec fossil fuel-fired power plants in the PEMA are estimated to be 16 metric tons (18 short tons), considerably below the cap.

Ontario’s Cessation of Coal Use Regulation – Atikokan, Lambton, Nanticoke and Thunder Bay Generating Stations (O. Reg. 496/07) came into effect in August 2007 and ensures that coal is not to be used to generate electricity at Atikokan, Lambton, Nanticoke, and Thunder Bay Generating Stations after December 31, 2014. The closure of Lakeview Generating Station in April 2005 (O. Reg. 396/01) has already eliminated annual emissions of approximately 5,000 metric tons (5,500 short tons) of NOX. To date, Ontario has shut down 10 out of 19 coal units, resulting in significant emission reductions. This includes an 85 percent decrease in NOX emissions from coal plants between 2003 and 2011.

Ontario has been engaged in a number of clean energy projects to offset coal-fired electricity generation. By the end of 2011, the Ontario Power Authority executed 12,076 renewable energy contracts, totaling nearly 10,380 MW.

To ensure that the 5,000 metric ton (5,500 short tons) cap is met for the Quebec portion of the PEMA, Quebec’s Clean Air Regulation, which came into effect on June 30, 2011, introduced a specific cap of 2,100 metric tons (2,310 short tons) of NOX per year for the Sorel Tracy plant. This plant is used mainly during peak periods. After emitting 653 metric tons (718 short tons) of NOX in 2009, it easily met the cap in 2010, with only 16 metric tons (18 short tons) of NOX.

Proposed National Guideline on Renewable Low-Impact Electricity

Control and reduce NOXemissions in accordance with a proposed national Guideline on Renewable Low-Impact Electricity.

A notice of a draft Guideline on Renewable Low-Impact Electricity (Green Power Guideline) was published in the Canada Gazette, Part I, in 2001. This guideline was developed to provide national guidance on environmentally preferable electricity products and their generation in Canada, and to establish criteria for environmental labeling of qualifying electricity products under the EcoLogoTM Program. Certification criteria derived from the draft guideline are being used to certify qualifying electricity products. Most Canadian provinces have developed their own specifications and requirements for renewable low-impact electricity. Notably, British Columbia and New Brunswick require their facilities to meet the certification criteria for renewable low-impact electricity, as defined by the EcoLogoTMProgram. The EcoLogoTM certification criteria for Renewable Low-Impact Electricity are periodically reviewed and updated to promote continuous improvement in the environmental performance of this industry.

Measures to Reduce VOCs

Reduce VOC emissions by developing two regulations--one on dry cleaning and another on solvent degreasing--and using VOC emission limits for new stationary sources.

The final provision of the Tetrachloroethylene (PERC) (Use in Dry Cleaning and Reporting Requirements) Regulations came into effect in August 2005. The environmental objective of the regulations is to reduce the ambient PERC concentration in the air to below 0.3 micrograms per cubic meter (μg/m3). The risk management goal of the regulations is to reduce PERC use in dry cleaning in Canada to less than 1,600 metric tons (1,760 short tons) per year. Environment Canada completed a use pattern study and a statistical analysis of ambient air concentrations of PERC across Canada in 2009, indicating that both the regulatory objective and goal have been achieved.

The Solvent Degreasing Regulations, which took effect in July 2003, froze the consumption of trichloroethylene (TCE) and PERC in affected cold and vapor-solvent degreasing facilities for three years (2004 to 2006) at then-current levels based on historical use. Beginning in 2007, the annual consumption levels were reduced by 65 percent for affected facilities.

Measures for NOX and VOC Emissions to Attain the CWS for Ozone

If required to achieve the CWS for ozone in the PEMA by 2010, measures will be in place to reduce NOx emissions by 2005 and implemented between 2005 and 2010 for key industrial sectors and measures to reduce VOC emissions from solvents, paints, and consumer products.

The CWS committed provincial jurisdictions to developing implementation plans outlining the comprehensive actions being taken within each jurisdiction to achieve the standards. As the province of Quebec is not a signatory to the CWS, it is not required to develop an implementation plan. However, the following sections describe the measures that Quebec and Ontario have put in place to reduce emissions of NOX and VOCs.

In keeping with Ontario’s commitment to reduce NOXand VOC emissions by 45 percent by 2010 for achievement of the ozone standard, the province developed a Clean Air Action Plan that includes actions on industrial and vehicle emissions. These actions have contributed to the province’s achievement of the emission reduction targets for both pollutants by 2010.

Ontario’s Clean Air Action Plan for reducing smog causing emissions includes the Industry Emissions--Nitrogen Oxides and Sulphur Dioxide Regulation (O. Reg. 194/05), which introduced emissions trading of NOX and SO2 in seven industrial sectors in 2006. Since the program’s inception, NOX and SO2 emissions from facilities regulated under Regulation 194/05 have shown a downward trend due to a number of factors including lower economic activity and some facility improvements. More information on Ontario’s Regulation 194/05 (Industry Emissions--Nitrogen Oxides and Sulphur Dioxide) can be found at

The Clean Air Action Plan also includes the province’s Drive Clean program. Since 1999, Ontario has had in place a vehicle emissions inspection and maintenance program to further reduce emissions of smog precursors. From 1999 through 2010, smog-causing emissions of NOX and hydrocarbons (VOCs) from light-duty vehicles were reduced by an estimated 335,000 metric tons (368,500 short tons).

Further details on Ontario’s Clean Air Action Plan can be found at

The federal government has worked in collaboration with provinces, territories, and stakeholders and developed a new air quality management system that will further reduce ozone-causing emissions. The system includes new ambient air quality standards for ozone that are more stringent and replace the existing Canada-wide Standard, and new national emission standards for key industrial sectors. In addition, further actions to address all sources of NOX and VOCs could be undertaken by the provinces and territories to achieve the new ambient air quality standards and improve air quality. Further details on this new system can be found in Section 3 of this report: New Actions on Acid Rain, Ozone, and PM.

VOC emissions from the manufacture and use of consumer and commercial products, such as cleaning products, personal care products, and paints, contribute significantly to the formation of smog. The federal government has therefore taken actions to reduce VOC emissions from consumer and commercial products.

Two regulations controlling VOCs in products were finalized in 2009. The Volatile Organic Compound (VOC) Concentration Limits for Automotive Refinishing Products Regulations and the Volatile Organic Compound (VOC) Concentration Limits for Architectural Coatings Regulations were finalized and published in Canada Gazette, Part II on July 8 and September 30, 2009, respectively. Environment Canada is currently examining other product categories to identify additional opportunities for the reduction of VOC emissions.

Actions by the Province of Quebec

Quebec has made progress in meeting its Ozone Annex commitments by way of several regulatory actions. The Clean Air Regulation, which came into effect on June 30, 2011, and replaced the Regulation Respecting the Quality of the Atmosphere, contains stricter standards aimed at reducing NOx emissions from new and modified industrial and commercial boilers, in accordance with Canadian Council of Ministers of the Environment (CCME) guidelines. In addition, when burners on existing units must be replaced, the replacements must be low-NOx burners.

With respect to VOC emissions, the standards in the Clean Air Regulation aim to reduce emissions from the manufacture and application of surface coatings, commercial and industrial printing, dry cleaning, above-ground storage tanks, petroleum refineries, and petrochemical plants.

Quebec’s Regulation Respecting Mandatory Reporting of Certain Emissions of Contaminants into the Atmosphere, which came into force in 2007, requires Quebec enterprises to report atmospheric releases of certain contaminants. It determines the reporting thresholds, the information that these enterprises will have to provide, and the parameters applicable to the calculation of the quantities of these contaminants. The Regulation allows for improved information on emission sources of air contaminants across the province, including emissions of VOCs and NOx. Quebec enterprises whose annual VOC emissions exceed 10 metric tons (11 short tons) and annual NOx emissions exceed 20 metric tons (22 short tons) are required to report their emissions.

Pursuant to its Regulation Respecting Petroleum Products and Equipment, Quebec is currently applying provisions aimed at reducing gasoline volatility during the summer months in the city of Montreal and the Gatineau to Montreal section of the Windsor–Quebec City corridor. Quebec is also evaluating the possibility of introducing amendments to the above regulation to address vapor recovery initiatives, including gasoline storage, transfer depots, and service stations, regardless of whether they are new or existing facilities, in the Quebec portion of the Windsor–Quebec City corridor. The city of Montreal is currently enforcing regulatory provisions concerning gasoline vapor recovery in its territory.

Actions by the Province of Ontario

Ontario has met its commitments under the Ozone Annex to reduce emissions of NOx and VOCs in the Ontario portion of the PEMA. Ontario has implemented the following programs, regulations, and guidelines:

  • The Emissions Trading regulation (O. Reg. 397/01), which establishes caps for NOx and SO2 emissions from the electricity sector.
  • The Ontario Drive Clean Program (established under O. Reg. 361/98, as amended by O. Reg. 578/05), which is a mandatory inspection and maintenance program for motor vehicles that identifies vehicles that do not meet provincial emission standards and requires them to be repaired. The Vehicle Emissions Enforcement Unit (Smog Patrol) complements the Drive Clean Program by conducting roadside inspections of heavy-duty and light-duty vehicles.
  • The Recovery of Gasoline Vapour in Bulk Transfers regulation (O. Reg. 455/94), which requires gasoline facility operators to install, maintain, and operate gasoline vapor recovery systems.
  • The Gasoline Volatility regulation (O. Reg. 271/91, as amended by O. Reg. 45/97), which sets limits for gasoline vapor pressure during the summer.
  • The Dry Cleaners regulation (O. Reg. 323/94), which requires mandatory environmental training every five years for at least one full-time employee of all dry cleaning establishments in Ontario.
  • Guideline A-5: New and Modified Combustions Turbines (1994), which sets limits for NOX and SO2 emissions from new and modified stationary combustion turbines.
  • Guideline A-9: New Commercial/Industrial Boilers and Heaters (2001), which imposes a NOX emission limit on new or modified large boilers and heaters in industrial installations.
  • The Airborne Contaminant Discharge Monitoring and Reporting regulation (O. Reg. 127/01), amended by O. Reg. 37/06 in February 2006, which harmonizes Ontario’s air emission reporting system with Environment Canada’s NPRI.

Beyond the Ozone Annex, Ontario is implementing the Industry Emissions--Nitrogen Oxides and Sulphur Dioxide regulation (O. Reg. 194/05), which sets limits on emissions of NOX and SO2 from seven industrial sectors in Ontario.

The province also amended the Local Air Quality regulation (O. Reg. 419/05) in 2007, 2009, and 2011 to introduce new/updated air standards and other tools to demonstrate and improve environmental performance. Since 2005, 68 new/updated air standards have been introduced, including several that address VOCs. Air standards are foundational elements of the regulation and are used to assess compliance or to trigger technology-based compliance approaches that address technological or economic challenges.

United States

NOX and VOC Program Updates 

  • From 2003 to 2008, implementing the NOXtransport emission reduction program, known as the NOXSIP Call, in the PEMA states that are subject to the rule.
  • Starting in 2009, implementing the CAIRNOXozone season program in the PEMA states subject to the program.
  • Implementing existing U.S. vehicle, nonroad engine, and fuel quality rules in the PEMA to achieve both VOC and NOX reductions.
  • Implementing existing U.S. rules in the PEMA for the control of emissions from stationary sources of hazardous air pollutants and of VOCs from consumer and commercial products, architectural coatings and automobile repair coatings.
  • Implementing 36 existing U.S. NSPS to achieve VOC and NOX reductions from new sources.

U.S. Environmental Protection Agency (EPA) stopped administering the NOX Budget Trading Program (NBP) under the NOX SIP call following the 2008 ozone season. Starting in 2009, the NOX annual and ozone season programs under CAIR took effect. See the 2010 Canada-United States Air Quality Agreement Progress Report for more information on the transition from the NBP to CAIR.

Current CAIR Implementation in PEMAStates

Figure 11. PEMA Region and CAIR

PEMA Region and CAIR

Source: U.S. EPA, 2012

Ozone Season Reductions

The CAIR NOX ozone season program includes EGUs as well as, in some states, large industrial units that produce electricity or steam primarily for internal use and that have been carried over from the NBP. Examples of these units are boilers and turbines at heavy manufacturing facilities, such as paper mills, petroleum refineries, and iron and steel production facilities. These units also include steam plants at institutional settings, such as large universities or hospitals. In 2011, there were 3,307 EGUs and industrial facility units (see Table 2) at 954 facilities in the CAIR NOX ozone season program; of these, 1,906 were covered units in the Ozone Annex PEMA.

Table 2 shows that in 2011, there were 3,307 electricity generating units (EGUs) and industrial facility units at 954 facilities in the CAIR NOx ozone season program, of these, 1,906 were covered units in the Ozone Annex PEMA. The CAIR NOx ozone season program includes EGUs, as well as in some states large industrial units that produce electricity or steam primarily for internal use and that have been carried over from the NOx Budget Trading Program.(NBP).

Table 2. Affected Units in CAIR NOx and SO2 Annual and CAIR NOx Ozone Season Programs
FuelCAIR NOX Ozone Season ProgramCAIR NOX and SO2Annual Programs
Coal EGUs845895
Gas EGUs1,6851,969
Oil EGUs543451
Industrial Units2030
Unclassified EGUs24
Other Fuel EGUs2926
Total Units3,3073,345


  • “Unclassified” units have not submitted a fuel type in their monitoring plan and did not report emissions.
  • “Other” fuel refers to units that burn fuel such as waste, wood, petroleum coke, and tire-derived fuel

Source: U.S. EPA, 2012

Between 2005 and 2011, ozone season NOX emissions from sources in the CAIR program alone have fallen 239,000 short tons (217,273 metric tons), a decrease of 30 percent. From 2010 to 2011, ozone season NOX emissions from sources in the CAIR NOX ozone season program decreased by 28,000 short tons (25,455 metric tons) (five percent), reversing a one-year increase in emissions from 2009 to 2010. Units in the seasonal program reduced their overall NOX emissions from 1.5 million short tons (1.4 million metric tons) in 2000 to 566,000 short tons (514,545 metric tons) in 2011 (Figure 12), nine percent below the regional emission budget of 624,698 short tons (567,907 metric tons). Despite a small increase in heat input from 2000 levels in 2011, the 65 percent improvement in NOX rate accounted for this reduction in total summer NOXemissions. In the PEMA states, NOX rate decreased by 62 percent.

In addition to the CAIR NOX ozone season program and the former NBP, prior programs such as the Ozone Transport Commission’s (OTC) NOX Budget Program and current regional and state NOX emission control programs have also contributed significantly to the ozone season NOXreductions achieved by sources in 2011.

Compliance: In 2011, all CAIRozone season sources were in compliance.

Figure 12. Ozone Season Emissions from CAIR NOX Ozone Season Sources

Ozone Season Emissions from <abbr>CAIR</abbr> NOX Ozone Season Sources

Source: U.S. EPA, 2012

Annual NOX Reductions 

In 2011, the third year of the CAIR NOXannual program, NOX emissions from all ARPand CAIR units were 1.7 million short tons (1.5 million metric tons) lower (46 percent) than in 2005 and 3.2 million short tons (2.9 million metric tons) lower (62 percent) than in 2000.

Emissions from CAIR NOX annual program sources alone were 1.35 million short tons (1.23 million metric tons) in 2011, 146,000 short tons (132,727 metric tons) (10 percent) below the 2011 CAIR NOX annual program’s regional budget of 1.5 million short tons (1.4 million metric tons). Annual NOXemissions were 1.3 million short tons (1.2 million metric tons) lower (49 percent) than in 2005, and 74,000 short tons (67,273 metric tons) lower (5 percent) than in 2010.

Although the ARP and CAIRNOX programs were responsible for a large portion of these annual NOXreductions, other programs -- such as the NBP, the OTC NOX Budget Program, and other regional and state NOX emission control programs -- also contributed significantly to the annual NOX reductions achieved by sources in 2011.

Compliance: In 2011, only one CAIRfacility did not hold enough allowances to cover its emissions for the NOX  annual program. That facility automatically surrendered a 3-for-1 penalty deduction for a total of 9 allowances from the next year’s allowance allocation under the NOX annual program.

NSPS: All of the 36 categories of NSPS identified in the Ozone Annex for major new NOX and VOC sources are promulgated and in effect. In addition, the U.S. EPA finalized the NSPS for Stationary Compression-Ignition Internal Combustion Engines in July 2006, which is helping these sources achieve significant reductions in NOX and VOC emissions. Furthermore, in December 2007, the U.S. EPA finalized an additional nationally applicable emission standard--an NSPS for NOX, carbon monoxide (CO), and VOC emissions from new stationary spark-ignited internal combustion engines (for more information on the Spark Ignited Internal Combustion Engine rule, see

In February 2006, the U.S. EPA promulgated the NSPS for utility and industrial boilers and combustion turbines. The updated standards for NOX, SO2, and direct filterable PM are based on the performance of recently constructed boilers and turbines. In February 2012, the U.S. EPA promulgated amendments to the NSPS for utility boilers to reflect improvement in the controls for NOX, SO2, and direct filterable PM. The U.S. EPA is also currently amending the NSPS for petroleum refineries that was promulgated in 2008 to address issues regarding flares and process heaters.

VOC Controls on Smaller Sources: In 1998, the U.S. EPA promulgated national rules for automobile repair coatings, consumer products, and architectural coatings. The compliance dates for these rules were January 1999, December 1998, and September 1999, respectively. From a 1990 baseline, the consumer products and architectural coatings rules are each estimated to achieve a 20 percent reduction in VOC emissions, and the automobile repair coatings rule is estimated to achieve a 33 percent reduction in VOC emissions. The U.S. EPA is planning to review and revise, as necessary, the automobile repair coatings, consumer products, and architectural coatings rules.

In addition, the U.S. EPA had previously scheduled for regulation 18 other categories of consumer and commercial products under section 183(e) of the CAA. To date, U.S. EPA has regulated or issued guidance on all 18 categories, including shipbuilding and repair coatings; aerospace coatings; wood furniture coatings; flexible packaging printing materials; lithographic printing materials; letterpress printing materials; industrial cleaning solvents; flatwood paneling coatings; aerosol spray paints; paper, film, and foil coatings; metal furniture coatings; large appliance coatings; portable fuel containers; miscellaneous metal products coatings; plastic parts coatings; auto and light-duty truck assembly coatings; miscellaneous industrial adhesives; and fiberglass boat manufacturing materials.

Motor Vehicle Control Program: To address motor vehicle emissions, the United States committed to implementing regulations for reformulated gasoline; reducing air toxics from fuels and vehicles; and implementing controls and prohibitions on gasoline and diesel fuel quality, emissions from motorcycles, light-duty vehicles, light-duty trucks, highway heavy-duty gasoline engines, and highway heavy-duty diesel engines.

On the fuel side, the U.S. EPA fully phased in requirements for reformulated gasoline in nonattainment areas in 1995 and implemented low-sulfur requirements for gasoline in 2005 and on-road diesel fuel in fall 2006 (30 ppm and 15 ppm sulfur levels, respectively).

The U.S. EPA implemented much tighter PM emission standards for highway heavy-duty engines in 2007 and correspondingly tighter NOX standards in 2010. The U.S. EPA implemented Tier 2 exhaust and evaporative standards for light-duty cars and trucks from 2004 to 2009. The U.S. EPA has also implemented on-board refueling standards and on-board diagnostic systems (OBD II) requirements for these vehicles. In 2004, the U.S. EPA published new motorcycle emission standards, which took effect in 2006 and 2010.

Nonroad Engine Control Program: The U.S. EPA has applied engine standards in all five nonroad engine categories identified in the Ozone Annex: aircraft, compression-ignition engines, SI engines, locomotives and marine engines. Nonroad diesel fuel was aligned with on-highway diesel fuel at 15 ppm sulfur in 2010. Locomotive and marine diesel fuel was aligned with on-highway and nonroad diesel fuel at 15 ppm in 2012.

The U.S. EPA began regulating nonroad SI engines in 1997 with its small SI engine rule, which applies to lawn and garden engines under 25 horsepower (hp) (19 kilowatts [kW]). Marine outboard engines and personal watercraft engines were first regulated in 1998 and 1999, respectively. Since then, the U.S. EPA has implemented tighter standards covering a wider range of SI engines. The U.S. EPA published regulations for recreational vehicles and large SI engines in November 2002. These regulations cover snowmobiles, ATVs, off-highway motorcycles, and nonroad equipment with engines larger than 25 hp (19 kW). Phase-in of the emission reductions began with the 2004 model year, and full emission reductions will be achieved by the 2012 model year. The U.S. EPA’s Phase 3 standards for small SI engines including marine inboard and sterndrive engines began phase-in in 2010.

In addition, the U.S. EPA began regulating nonroad compression-ignition engines (diesels) with the 1996 model year and has now promulgated more stringent (Tier 4) standards for nonroad compression-ignition engines. The Tier 4 standards for nonroad diesels will phase in through 2014. New locomotive and marine engine standards (for engines less than 30 liters/cylinder) were finalized in March 2008 and took effect in 2008 for remanufactured locomotive and marine engines. Stringent Tier 3 standards began in 2009 for newly manufactured engines. Even more stringent Tier 4 standards requiring catalytic aftertreatment will phase in for most newly manufactured locomotive and marine engines beginning in 2014.

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Anticipated Additional Control Measures and Indicative Reductions


National Reductions

The North American Emission Control Area (ECA), covering the waters of Canada and the United States, took effect on August 1, 2012 and subjects ships to environmental standards that will significantly reduce air pollution. As a result of the ECA standards, NOX emissions from new ships will be reduced by 80 percent, SOX (oxides of sulfur) by 95 percent, and PM by 85 percent, when requirements are fully implemented. In 2009, the U.S. EPA finalized these standards in their domestic regulations and in summer 2012, Transport Canada’s proposed regulations were published, with final regulations to follow. Environment Canada’s Regulations Amending the Sulphur in Diesel Fuel Regulations are now in force and set a 1,000 ppm sulfur standard in marine diesel fuel available for large ships, in effect on June 1, 2014. The new diesel fuel standards will allow for a supply of cleaner shipping fuel, with the ECA standard of 1,000 ppm taking effect in January 2015.

Canada initiated a national vehicle scrappage program in January 2009. The program ended in March of 2011 after retiring more than 138,000 high-polluting vehicles of model year 1995 and earlier resulting in a total reduction of 5,600 metric tons (6,160 short tons) of NOX and VOC emissions. Canadians in every province were offered a selection of incentives as rewards for retiring their older vehicles that included $300 per vehicle, free transit passes, rebates on bicycles or replacement vehicles, and memberships in car-sharing programs, etc.

Since the federal government published the Regulatory Framework for Air Emissions in 2007, it has collaborated with the provinces, territories, and stakeholders and developed a new air quality management system. The system includes the establishment of national standards to reduce ozone precursor emissions from key industrial sectors and new ambient air quality standards for fine PM (PM2.5) and ozone. The new system is expected to reduce air pollutant emissions and improve air quality across the country, including in regions currently in attainment of the CWS for ozone and in the PEMA, as well as where ozone levels still exceed the CWS.

Quantitative Estimates

In the Ozone Annex, parties provided 2010 NOX and VOC emission reduction estimates associated with applying the control measures identified under Part III of the Annex. The parties further agreed to update these reduction forecasts to demonstrate that the obligations are being implemented and to ensure that quantitative estimates reflect any emission estimation methodology improvements. The largest source of NOX and VOC emissions in the Canadian PEMA region is transportation. Figure 13 shows that NOX and VOC emissions from transportation sources in the PEMA are expected to decrease by 60 percent and by nearly 62 percent, respectively, by 2025 from 1990 levels. Note that Canada will be switching to the Motor Vehicle Emission Simulator (MOVES) model in the summer of 2012, as well as incorporating new and additional spatial data to improve the transportation emission estimates.

Figure 13. Canadian Transportation NOX and VOC PEMA Emission Projections, 1990–2025

Canadian Transportation NOX and VOC PEMA Emission Projections, 1990–2025

Source: Environment Canada, 2012

Using national emission data, the specific NOX and VOC emission reduction obligations in the Ozone Annex reduced annual NOX emissions in the PEMA by 43 percent and annual VOC emissions in the PEMA by 42 percent by 2010, from 1990 levels (see Figure 14). Canada has developed new emission projections for 2025 based on the 2009 emissions data that took into consideration the impact of the recent economic slowdown and the latest economic projections. Figure 14 shows Canada’s projected emission reductions for 2025.

The projected emissions are based on the 2009 emission inventory and projected into the future using Environment Canada’s energy, emission, and economy forecast model (E3MC). Based on the projected Canadian emissions for 2025, it is estimated that annual NOX emissions in the PEMA will be reduced by 53 percent and annual VOC emissions in the PEMA by 52 percent by 2025, from 1990 levels.

Figure 14. Canadian NOX and VOC PEMAEmissions and Projections

Canadian NOX and VOC PEMA Emissions and Projections

Source: Environment Canada, 2012

United States

National Reductions

The U.S. EPA and the National Highway Traffic Safety Administration (NHTSA) have been working together on developing a National Program of harmonized regulations to reduce GHG emissions and improve fuel economy of light-duty vehicles. The agencies issued a Final Rulemaking (found at establishing standards for 2012 to 2016 model year vehicles on April 1, 2010. The agencies proposed standards for model years 2017 to 2025 in November 2011, and are scheduled to finalize the standards in August 2012. The U.S. EPA, with NHTSA, also finalized heavy-duty GHG standards in a 2011 joint rulemaking that will phase in between 2014 and 2018. In addition to reducing the emissions of GHGs, the heavy-duty GHG standards will also reduce criteria pollutants, including significant reductions in NOX and air toxics emissions.

In another action, the U.S. EPA finalized stringent new standards for ocean going vessels (engines larger than 30 liters per cylinder) in 2009. These standards, which phase in through 2016, are linked to the joint establishment of ECAs around the U.S. and Canadian coasts and internal waters such as the Great Lakes. These standards will impose stringent NOX standards for ships operating in the ECA and will greatly reduce PM by reducing the sulfur allowed in fuel used in the ECA. NOXemissions are expected to be reduced by 80 percent, SOXby 95 percent, and PM by 85 percent when the requirements are fully implemented.

Area-Specific Reductions

The U.S. EPA is implementing NOX and VOC control measures in specific areas, as required by applicable provisions of the CAA. The measures include NOX and VOC reasonably available control technology, marine vessel loading, treatment storage and disposal facilities, municipal solid waste landfills, onboard refueling, residential wood combustion, vehicle inspection and maintenance, reformulated gasoline, cement kilns, internal combustion engines, large non-utility boilers and gas turbines, fossil fuel-fired utility boilers, and additional measures needed to attain the NAAQS.

Quantitative NOX and VOC Emission Reductions

In the Ozone Annex, the United States provided NOXand VOC emission reduction estimates associated with the application of the control strategies identified under Part III B and Part IV of the Annex. The U.S. EPA has updated the estimates using more recent national trends data available in 2012.

The specific emission reduction obligations (see Figure 15) are now estimated to reduce annual NOX emissions in the PEMA by 63 percent (versus the predicted overall emission reduction rate of 43 percent) and annual VOC emissions in the PEMA by 61 percent (versus the predicted overall emission reduction rate of 36 percent) by 2012, from 1990 levels. The U.S. 2012 estimate is based on emission projections for mobile on-road and nonroad sources and holding emissions constant for other sectors from year 2008, and for the electric utilities from year 2011.  

Figure 15. U.S. NOX and VOC PEMAEmissions and Projections

U.S. NOX and VOC PEMA Emissions and Projections

Source: U.S. EPA, 2012

Joint Commitment

Reporting PEMAEmissions

Provide information on all anthropogenic NOXand all anthropogenic and biogenic VOC emissions within the PEMA from a year that is not more than two years prior to the year of the biennial progress report, including:

  • Annual ozone season (May 1 to September 30) estimates for VOC and NOX emissions by the sectors outlined in Part V, Section A, of the Ozone Annex; and
  • NOX and VOC five-year emission trends for the sectors listed above, as well as total emissions.

Canada and the United States have complied with emission reporting requirements in the Ozone Annex. Canada’s NPRI provides a comprehensive emissions inventory for pollutants such as NOX, VOCs, SO2, total PM, PM10, PM2.5, and CO that contribute to acid rain, ground-level ozone and components of smog. This comprehensive inventory is based on two components:

  • Mandatory annual reporting of emissions by more than 8,700 facilities; and
  • Emission estimates compiled for various sources such as motor vehicles, residential heating, forest fires, and agricultural activities.

The information reported by facilities is publicly available on the Environment Canada website at

The compilation of the comprehensive 2010 air pollutant emissions summaries were completed in early 2012, and the emission data have been included in this 2012 Progress Report. The Canadian emission summaries are available on Environment Canada’s website at

New emission inventory modeling files for the calendar years 2009 and 2010 are now available and include updated information on the temporal and the spatial allocation of the emissions for various sources and pollutants.

In the United States, the U.S. EPA develops the National Emissions Inventory (NEI) as a comprehensive inventory covering emissions in all U.S. states for point sources, nonpoint sources, on-road mobile sources, nonroad mobile sources and natural sources. The NEI includes both criteria pollutants and hazardous air pollutants. The U.S. regulations require that states report criteria pollutant emissions from large point sources every year and for all sources once every three years. The states voluntarily submit HAP emissions. The 2008 NEI is the most recent comprehensive national compilation of emissions sources collected from state, local, and tribal air agencies as well as emission information collected from the EPA emission programs including the Toxics Release Inventory (TRI), emission trading programs such as the Acid Rain Program, and data collected as part of EPA regulatory development for reducing emissions of air toxics. The next comprehensive NEI for 2011 is expected to be released in mid-2013.

Table 3 shows preliminary 2010 U.S. and Canadian emissions in the PEMA. Note that Canadian 2010 biogenic emissions are not currently available. Most of the estimated annual biogenic VOC emissions occur during the ozone season. For the U.S. 2010 emissions, 2008 year emissions are used as a surrogate for 2010 because state-level (PEMA) data is not readily available for 2010. Ozone season emissions are estimated as a 5-month fraction of the annual emission category totals. Figure 16 and Figure 17 show U.S. emission trends in these areas for 1990 through 2010. The trend in the PEMA states is similar to the U.S. national trend. For NOX, most of the emission reductions come from on-road mobile sources and electric power generation. The sharp decline in EGU NOX after 2008 may illustrate the effect of the CAIRNOX ozone season program starting in 2009.

Over this same period, the reductions in VOC emissions are primarily from on-road and nonroad mobile sources and solvent utilization. VOC emissions from non-industrial fuel combustion sources increased after 1998 and then returned to a downward trend by 2000, but saw a significant spike upward in 2001. This general rise in non-industrial fuel combustion VOC emissions from 2001 to 2002 is in part due to improved emission characterization methods for non-industrial fuel combustion sources (e.g., commercial and institutional sources such as office buildings, schools, and hospitals). There are also changes to VOC emissions around 2005 when compared to the 2010 Report due to a correction for VOC emission rates for residential wood combustion and a more complete exclusion of wildfire data.

Table 3 shows preliminary 2010 U.S. and Canadian emissions of NOx and VOCs by emissions category in the PEMA in short tons and metric tons, respectively. Annual and ozone season emissions are presented.

Table 3. PEMA Emissions, 2010

Table 3.1 Canadian PEMARegion: Annual and Ozone Season Emissions
Emissions Category2010 Annual2010 Ozone Season
1000 Short Tons1000 Metric Tons1000 Short Tons1000 Metric Tons1000 Short Tons1000 Metric Tons1000 Short Tons1000 Metric Tons
Industrial Sources7467837532294440
Non-industrial Fuel Combustion47431009124223229
Electric Power Generation272500141300
On-road Transportation168152888075693834
Nonroad Transportation2322111561421131027568
Solvent Utilization0026123700112102
Other Anthropogenic Sources659788334138
Forest Fires00000000
Biogenic Emissions----------------
TOTALS without Forest Fires and Biogenics554504784713262238342311
Table 3.2 U.S. PEMA States: Annual and Ozone Season Emissions
Emissions Category2010 Annual2010 Ozone Season
1000 Short Tons1000 Metric Tons1000 Short Tons1000 Metric Tons1000 Short Tons1000 Metric Tons1000 Short Tons1000 Metric Tons
Industrial Sources5595071821652332116976
Non-industrial Fuel Combustion3443121941761431307381
Electric Power Generation1,2811,162151353448566
On-road Transportation2,2122,007977886923837369407
Nonroad Transportation1,1131,0091,020925464421386425
Solvent Utilization001,2821,16300485534
Other Anthropogenic Sources60544624192523175193
Forest Fires*112321    
Biogenic Emissions*1501363,8173,463    
TOTALS without Forest Fires and Biogenics5,5695,0534,1313,7482,3222,1071,5631,723

Note: Short tons and metric tons are rounded to the nearest thousand. Totals in rows may not equal the sum of the individual columns.

Source: Environment Canada and U.S. EPA, 2012

Figure 16. U.S. NOX Emission Trends in PEMAStates, 1990–2010

U.S. NOX Emission Trends in PEMA States, 1990–2010

Note: The scales used to display U.S. and Canadian emissions in these figures are significantly different.

Source: U.S. EPA, 2012

Figure 17. U.S. VOC Emission Trends in PEMAStates, 1990–2010

U.S. VOC Emission Trends in PEMA States, 1990–2010

Source: U.S. EPA, 2012 

Figure 18 and Figure 19 show Canadian NOX and VOC PEMAemission trends for 1990 through 2010. For NOX, most of the reductions come from on-road mobile sources and electric power generation, with increases in non-industrial fuel combustion and other anthropogenic sources. Similar reductions and increases were observed for VOC emissions. VOC emission reductions were primarily from on-road mobile sources, electric power generation, industrial sources, and solvent utilization, with a slight increase in non-industrial fuel combustion.

Figure 18. Canada NOX Emission Trends in the PEMA Region, 1990–2010

Canada NOX Emission Trends in the PEMA Region, 1990–2010

Source: Environment Canada, 2012

Figure 19. Canada VOC Emission Trends in the PEMARegion, 1990–2010

Canada VOC Emission Trends in the PEMA Region, 1990–2010

Source: Environment Canada, 2012

Reporting Air Quality for All Relevant Monitors within 500 km of the Border between Canada and the United States

Both the United States and Canada have extensive networks to monitor ground-level ozone and its precursors. Both governments prepare routine reports summarizing measurement levels and trends. The latest quality-assured complete data set from both countries is 2010.

Ambient Levels of Ozone in the Border Region

Figure 20 illustrates ozone conditions in the border region in the metrics of national standards. The reference period is 2008 through 2010. Only data from sites within 500 km (310 miles) of the United States–Canada border that met data completeness requirements were used to develop this map. Figure 20 shows that higher ozone levels occur in the Great Lakes and Ohio Valley regions and along the U.S. East Coast. Lowest values are generally found in the West and in Atlantic Canada. Levels are generally higher downwind of urban areas, as can be seen in the western portions of lower Michigan, though the full detail of urban variation is not shown. For ozone, the data completeness requirement was that a site’s annual fourth-highest daily maximum 8-hour concentration, in parts per billion (ppb) by volume, be based on 75 percent or more of all possible daily values during the U.S. EPA-designated ozone monitoring seasons.

Figure 20. Ozone Concentrations along the United States–Canada Border (Three-Year Average of the Fourth-highest Daily Maximum 8-hour Average) 2008–2010

Ozone Concentrations along the United States–Canada Border (Three-Year Average of the Fourth-highest Daily Maximum 8-hour Average) 2008–2010

Note: Data contoured are the 2008–2010 averages of annual fourth-highest daily values, where the daily value is the highest running 8-hour average for the day. Sites used had at least 75 percent of possible daily values for the period.

Sources: Environment Canada NAPS Network Canada-wide Database, 2010 (; U.S. EPA Air Quality System (AQS) Data Mart ().

Ambient Concentrations of Ozone, NOX, and VOCs

Annual ozone levels over the 1995 to 2010 time period are presented in Figure 21, based on information from longer-term eastern monitoring sites within 500 km (310 miles) of the United States–Canada border. Ozone levels have decreased over the period with a notable decline in ozone levels since 2002. The lower ozone levels shown for 2004 and 2009 were due, in part, to the cool, rainy summers in eastern North America. There is also a complex regional pattern in ozone level variations, which is not evident from the graph shown in Figure 21. Figure 22 and Figure 23 depict the average ozone season levels of ozone precursors NOX and VOCs in the eastern United States and Canada. These measurements represent information from a more limited network of monitoring sites than is available for ozone. Figure 24 shows the network of monitoring sites actually used to create the trend graphs in Figure 21 through Figure 23. The data in Figure 22 and Figure 23 represent measurements for the ozone season (i.e., May through September). Although NOX and VOC concentrations have fluctuated over recent years, because VOC concentrations are influenced by temperature, these fluctuations are most likely due to varying meteorological conditions. Overall, the data indicate a downward trend in the ambient levels of both NOX and VOCs. The limited correspondence between composite ozone and precursor trends could reflect the regional complexity of the problem as well as network limitations. Note that the NOX and VOC concentration trends shown in Figures 22 and 23 are based on a limited number of U.S. and Canadian monitoring sites with sufficient long-term data availability. Thus, the trends in Figures 22 and 23 may reflect slightly different values than previous versions of the Progress Report.

Recently in the United States, there has been much investigation into the relationship between NOX emission reductions and observed concentrations of ambient ozone in the PEMA states. Generally, a strong association exists between areas with the greatest NOX emission reductions and downwind monitoring sites measuring the greatest improvements in ozone.

From 2008 to 2010, reductions in NOX emissions during the ozone season from power plants under the NOX SIP Call, ARP, and CAIR have continued to contribute to significant regional improvements in ambient total nitrate (NO3- plus HNO3) concentrations. For instance, annual mean ambient total nitrate concentrations for 2008 to 2010 in the Mid-Atlantic region were 45 percent less than the annual mean concentration in 1989 to 1991. These improvements can be partly attributed to added NOX controls installed for compliance with the NOX SIP Call and CAIR. More information on the changes in ozone concentrations before and after implementation of the NBP and CAIR as well as a comparison of regional and geographic trends in ozone levels to changes in meteorological conditions (such as temperature) and NOXemissions from CAIR sources is available at

Figure 21. Annual Average Fourth-Highest Daily Maximum 8-hour Ozone Concentration for Sites within 500 km of the United States–Canada Border, 1995–2010

Annual Average Fourth-Highest Daily Maximum 8-hour Ozone Concentration for Sites within 500 km of the United States–Canada Border, 1995–2010

Source: U.S. EPA and Environment Canada, 2012

Figure 22. Average Ozone Season (May–September) 1-hour NOX Concentrations for Sites within 500 km of the United States–Canada Border, 1995–2010

Average Ozone Season (May–September) 1-hour NOX Concentrations for Sites within 500 km of the United States–Canada Border, 1995–2010

Source: U.S. EPA and Environment Canada, 2012

Figure 23. Average Ozone Season (May–September) 24-hour VOC Concentrations for Sites within 500 km of the United States–Canada Border, 1997–2010

Average Ozone Season (May–September) 24-hour VOC Concentrations for Sites within 500 km of the United States–Canada Border, 1997–2010

Source: U.S. EPA and Environment Canada, 2012

Figure 24. Network of Monitoring Sites Used to Create Graphs for Ambient Ozone, NOX, and VOC Levels

Network of Monitoring Sites Used to Create Graphs for Ambient Ozone, NOX, and VOC Levels

Source: U.S. EPA and Environment Canada, 2012

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[1]One metric ton is equal to 1.1 short tons.

[2]See for example: Schwede, D., L. Zhang, R. Vet, G. Lear, 2011. An intercomparison of the deposition models used in the CASTNET and CAPMoN networks. Atmospheric Environment, 45, 1337-1346.

[3]Connecticut, Delaware, Illinois, Indiana, Kentucky, Maine, Maryland, Massachusetts, Michigan, New Hampshire, New York, New Jersey, Ohio, Pennsylvania, Rhode Island, Vermont, West Virginia, and Wisconsin.

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