Section 1:
          Commitments

Acid Rain Annex

Overview

Since the Acid Rain Annex was developed as part of the original Air Quality Agreement in 1991-to address sulfur dioxide (SO2) and nitrogen oxides (NOx) emissions, particularly from electric power generation, as well as visibility protection, preventing air quality deterioration in clean areas, and emissions monitoring-the United States and Canada have taken significant actions to address acid rain. Both countries have established objectives for emission limitations or reductions, programs to implement these objectives, as well as timetables for implementation.

Progress on Canadian and U.S. Sulfur Dioxide Emission Reductions1

CANADA

Canada has been very successful in reducing the emissions of SO2, a principal cause of acid rain.2 In 2001, SO2 emissions in the seven easternmost provinces, where elevated acid deposition continues to damage sensitive ecosystems, were 28 percent below the eastern Canada 2.3 million tonne3 cap, even though the cap expired in December 1999. Canada's total SO2 emissions have decreased about 50 percent since 1980, to 2.4 million tonnes in 2002, or 25 percent below the national cap. (See Figure 1 to compare eastern Canada emissions to national emissions and from 1980 to 2001.)

Figure 1. Canadian SO2 Emissions from Acid Rain Sources* (1980-2001)

* Total SO2 emissions    Source: Environment Canada

The Canada-wide Acid Rain Strategy for Post-2000 serves as a framework for addressing the country's acid rain problem. The long-term goal of the Strategy is to achieve critical loads4 for acid deposition for aquatic and terrestrial ecosystems. As part of the Strategy, the provinces of Ontario, Quebec, New Brunswick, and Nova Scotia all committed to an additional 50 percent reduction in their SO2 emissions beyond their 1985 Eastern Canada Acid Rain Program targets by 2010.5 Although these provinces have not yet finalized plans for implementing the new reductions, each has taken significant steps towards identifying measures for industrial sectors to achieve the specified reductions.

UNITED STATES

The United States has made substantial progress in reducing SO2 emissions, with the highest level of reduction being achieved by the electric power sector. By 2003, four years into Phase II of the Acid Rain Program, electric power sources in the United States reduced SO2 emissions by 5.1 million tons, or 32 percent, compared to 1990 levels, and more than 38 percent compared to 1980 levels. (Figure 2 shows the trend in SO2 emissions from 1980 to 2003 for electric power sources.)

Figure 2. U.S. SO2 Emissions from Electric Power Generation (1980-2003)

Source: EPA

Reductions from all source categories are expected to result in an SO2 emission reduction of 10 million tons annually from 1980 levels, with 8.5 million tons achieved by the electric power sector alone. In 2003, 3,497 electric generating units were subject to the SO2 provisions of the Acid Rain Program. (Annual fluctuations in the number of units participating in the program can result from retirements of some units and start-up of other units. For further details, visit http://cfpub.epa.gov/gdm/.)

Under the Acid Rain Program, the number of allowances allocated in a given year to a particular unit is determined by provisions in the Clean Air Act. All allowances are tradable, allowing them to be bought or sold. Every year, however, each individual source must hold enough allowances to equal or exceed its annual emissions. Allowances that are not used or sold in a given year are carried over (or banked) for future use. Banked emissions give sources the flexibility to emit more in years when energy demand is higher without affecting the total emissions cap under the program. Thus, annual fluctuations in SO2 emissions are expected.

In 2003, a total of 9.5 million allowances were allocated; however, sources actually emitted 10.6 million tons, decreasing total banked allowances by 1.1 million tons. Over time, affected sources will continue to use banked allowances to help comply with the more stringent Phase II requirements.

In 2003, national annual SO2 emissions under the Acid Rain Program were 400,000 tons (4 percent) higher than 2002 levels. Acid rain sources increased their heat input by 1.2 percent compared with 2002. One reason for this increase was that nuclear generation was down 2 percent in 2003, for the first time since 1998. More importantly, the price of natural gas rose by 55 percent in 2003, which resulted in approximately a 9 percent decline in natural gas generation. Sources were forced to use other types of generation to meet electricity demand, and that need was primarily filled by coal-fired and oil-fired generation. Despite the increase in emissions from 2002 levels, emissions under the Acid Rain Program were lower than 2000 levels and substantially lower than 1990 levels.

In addition to the electric power generation sector, other sources achieved reductions in SO2 emissions, including smelters and sulfuric acid manufacturing plants. The use of cleaner fuels in residential and commercial burners also contributed to the nearly 41 percent decline of SO2 emissions from all sources, compared to the 1980 level of 25.9 million tons. (For more details, visit the National Emission Inventory at www.epa.gov/airtrends/reports.html.)

Progress on Canadian and U.S. Nitrogen Oxides Emission Reductions6

CANADA

Though Canada has surpassed its NOx emission reductions target at power plants, major combustion sources, and metal smelting operations by 100,000 tonnes below the forecast level of 970,0007 tonnes, the country is continuing to develop programs to further reduce NOx emissions nationwide (see Section 2). In fact, the provinces and federal government are working together to achieve multi-pollutant emission reductions for pollutants contributing to particulate matter (PM) and ozone for key industrial sectors. Analytical studies have characterized pollutants that chemically react to form PM and ozone (including NOx). In addition, a range of emission control options, including measures and actions to reduce NOx emissions, were identified for several sectors contributing significantly to emissions of PM and ozone precursors. These options should be useful to assist jurisdictions in identifying best available technologies (BAT) and developing plans to meet the Canada-wide Standards for PM and ozone by 2010.

In addition to the efforts to reduce NOx emissions from stationary sources such as industries, Canada's agenda to reduce the largest source of NOx emissions-from vehicles and fuels-is aggressive. Details for implementing this agenda can be found in the ozone section of this report, under "Key Commitments and Progress" on page 10.

UNITED STATES

Coal-fired electric utility units affected by the NOx component of the Acid Rain Program continue to meet and exceed the annual 2 million ton reduction goal from what emission levels would have been without the program, set by Title IV of the 1990 Clean Air Act Amend-ments. In 2003, the 1,004 NOx program-affected units reduced their combined NOx emissions to 3.8 million tons. In addition, total NOx emissions for all Acid Rain Program-affected units were 4.2 million tons (see Figure 3 for NOx emissions from 1990 to 2003).

Figure 3. U.S. NOx Emissions from Electric Power Generation (1990-2003)

Source: EPA

Emissions Monitoring

CANADA8

Canada has met its commitments to estimate emissions of NOx and SO2 from new electricity utility units and existing electricity units greater than 25 megawatts (MW) using a method of comparable effectiveness to continuous emission monitoring systems (CEMS) and to investigate the feasibility of using CEMS by 1995. In Canada, emissions trading of SO2 and NOx is not currently a driver for electronic data reporting and CEMS. Currently, Environment Canada is undertaking an update of its 1993 guidelines for CEMS ("Protocols and Performance Specifications for Continuous Monitoring of Gaseous Emissions from Thermal Power Generation," Report EPS 1/PG/7).

Based, in part, on experience gained from the use of 40 CFR Part 75 specifications for CEMS in the United States. Although CEMS and data reporting requirements for power plants and industrial sources involved in emissions trading in the United States are not fully mirrored in Canada, it has been concluded that EPS 1/PG/7-compliant CEMS in Canada would meet Canadian monitoring requirements for domestic purposes. However, the feasibility of cross-border emissions trading is now being examined and indications are that certain enhancements of emissions monitoring in Canada would be required, if there was cross-border trading.

UNITED STATES9

Under the Acid Rain Program, affected units are required to measure and record emissions using CEMS or an approved alternative measurement method and report emissions electronically. All of the monitoring systems operate with a high degree of reliability. In fact, the percent monitor data availability (a measure of monitoring systems' reliability) for 2003 was 99 percent for coal-fired units. Additionally, in 2003, new audit capabilities were added, including software that performs hourly checks to catch errors, miscalculations, and oversights in monitoring and reporting systems. These audits help ensure the completeness, high quality, and integrity of emission data as well as highlight a number of potential “red flags” that require additional verification. Accurate emissions monitoring remains the backbone of trading program integrity.

Acid Deposition Monitoring, Modeling, Maps, and Trends10

Airborne pollutants are deposited on the earth's surface by three processes: 1) wet deposition (rain or snow); 2) dry deposition (particles and gases); and 3) deposition by cloud water and fog. Wet deposition is comparatively easy to measure using precipitation gauges and is regularly used as the reference measure for comparison with emissions.

Early 1990s sulfate and nitrate wet deposition data are illustrated in Figures 4 and 6, to be compared with 2002 data in Figures 5 and 7, to show trends. Wet sulfate deposition measurements are corrected for sea-salt, to derive non-sea-salt sulfate (nss SO42-), at sites in proximity to oceans. Blank areas on the maps indicate that measurement data were insufficient for the creation of deposition contours. Figures 4 and 6 are each five-year averages for baseline comparisons, whereas Figures 5 and 7 are the most recent annual averages for which data are available. Comparison of one year's data with a five-year average might introduce a bias due to specific weather conditions in 2002.

Source: NAtChem (www.msc-smc.gc.ca/natchem/index_e.html) and (http://NADP.sws.uiuc.edu)

Wet sulfate deposition is greatest in eastern North America, along an axis running from the Mississippi River to the lower Great Lakes. Decreasing deposition is evident in the Ohio River basin and southern Ontario and Quebec. Sulfate deposition of more than 25 kg/ha/yr persists south of Lake Erie; however, this amount is still a significant reduction from the early 1990s, when wet deposition in this area exceeded 30 kg/ha/yr.

The pattern for wet nitrate deposition is centered on the lower Great Lakes with an axis running from southeastern Missouri towards the Gulf of St. Lawrence. Comparison of 2002 data with the average for 1990 through 1994 shows persistent deposition.

Trends in wet deposition of sulfate and nitrate correspond to changes in SO2 and NOx emissions.

In Canada, wet and dry deposition components are measured in the federal Canadian Air and Precipitation Monitoring Network (CAPMoN) (www.msc-smc.ec.gc.ca/capmon). Some provincial governments (e.g., British Columbia, Alberta, Quebec, New Brunswick, Nova Scotia, Newfoundland) and the Northwest Territories support wet deposition sites. Recently a few additional sites in the more remote portions of Canada have been added to CAPMoN to provide more detailed deposition data. The United States has three coordinated acid deposition networks:

1. The National Atmospheric Deposition Program/National Trends Network (NADP/NTN), a collaboration of federal, state, and non-governmental organizations measuring deposition chemistry (http://nadp.sws.uiuc.edu).
2. The NADP/Atmospheric Integrated Research Monitoring (AIRMoN) network (a subnetwork of NADP operated by the National Oceanic and Atmospheric Administration).
3. The EPA/National Park Service Clean Air Status and Trends network (CASTNET), which provides dry deposition data (www.epa.gov/castnet).

Procedures for all U.S. and Canadian networks are standardized and contribute to an integrated, consistent dataset, which is accessible to the public at www.msc.ec.gc.ca/natchem/index_e.html.

Techniques for estimating dry deposition based on measurement data are undergoing steady improvement, as there are indications that this contribution to total deposition might have been underestimated in the past.

Preventing Air Quality Deterioration and Protecting Visibility11

In certain areas in the United States and Canada, many visitors are not able to see the spectacular vistas they expect. During much of the year, a veil of white or brown haze hangs in the air, obstructing the view. Most of this haze comes from air pollution, carried by the wind, often many hundreds of miles from where it originated.

CANADA

Pollution prevention, continuous improvement (CI), and Keeping Clean Areas Clean (KCAC) activities are all part of the Canada-wide Standards to prevent the deterioration of air quality and address the pollutants involved in visibility impairment. These activities are being conducted in addition to achieving the standards for PM and ozone by the 2010 target date. The KCAC principle recognizes that polluting “up to a limit” is not acceptable and that the best strategy to avoid future problems is to keep clean areas clean. CI applies to areas with ambient pollutant levels below those of existing standards but still above levels associated with observable health effects. The CI framework encourages jurisdictions to take remedial and preventive actions to reduce emissions from anthropogenic sources to the extent practicable. Jurisdictions are currently developing a national guidance document on CI/KCAC, which is expected to be completed in late 2004.

Federal, provincial, and territorial governments are working with stakeholders to establish implementation plans and programs for the Canada-wide Standard for PM2.5 and ozone that apply pollution prevention and best management practices. These practices could include ensuring that new facilities and activities incorporate the best available economically feasible technology (BAEFT) to reduce PM and ozone levels and reviewing new activities that might contribute to PM and ozone level increases.

One of the largest contributors from stationary sources is the electric power sector. Therefore, in January 2003, the government of Canada set out more stringent emission targets for key air pollutants from new fossil fuel power plants in "New Source Emission Guidelines for Thermal Electricity Generation" issued under the Canadian Environmental Protection Act (CEPA) of 1999. These guidelines are intended to provide national emission standards for application by the provinces to new coal-, oil-, and gas-fired, steam-electric power plants. The new guidelines include revised emission limits for SO2, NOx, and PM, consistent with the performance capability of current BAEFTs. In particular, the new emission limits align with U.S. standards and best available control technology (BACT) determinations.

UNITED STATES

The U.S. Prevention of Significant Deterioration (PSD) program protects public health and the environment from adverse effects that could occur from the addition of new sources of air pollution. It also ensures that air quality in many areas of the country remains better than levels mandated by the National Ambient Air Quality Standards (NAAQS). The program preserves and protects air quality in Class I areas by assessing impacts on visibility before construction permits are issued. Class I areas are national parks and wilderness areas such as the Grand Canyon, Yosemite, and the Great Smokies. The Regional Haze Program requires states to develop plans to improve visibility conditions at Class I areas with the goal of restoring natural visibility conditions in about 60 years. The first set of plans is due in early 2008.

SO2 and NOx gases are transformed in the atmosphere into fine particles of sulfates and nitrates. Sulfate and nitrate particles scatter and absorb light, impairing visibility and contributing to haze. Sulfates are generally the largest contributor to visibility impairment in both the East and the West. The visual range under naturally occurring conditions without air pollution in the United States is approximately 45 to 90 miles (75 to 150 km) in the East and 120 to 180 miles (200 to 300 km) in the West.

Data from the IMPROVE (Interagency Monitoring of Protected Visual Environments) network indicate little change in visibility during the past decade. (See Figure 8 for the annual average standard visual range.) The level of visibility impairment on the worst visibility days in the West is similar to the levels seen on the best visibility days in the East. In 2001, the mean visual range for the worst days in the East was only 18 miles (29 km), compared to 73 miles (117 km) for the best visibility. In the West, visibility impairment for the worst days remained relatively unchanged over the 10-year period, with the mean visual range for 2001 (63 miles, or 103 km) nearly the same as the 1992 level (61 miles, or 98 km). Although that 10-year period showed moderate improvements in some areas, overall visibility in the East is still significantly impaired in national parks and wilderness areas, especially on the haziest days.

Figure 8. Annual Standard Visual Range (2002)

Source: National Park Service

To implement the requirements of the Regional Haze Program, states work together in five regional planning organizations (RPOs) to develop strategies to address regional haze and visibility. The five RPOs are the Mid-Atlantic/ Northeast Visibility Union (MANE-VU), the State and Tribal Association of the Southeast (VISTAS), the Midwest RPO, the Central States Regional Air Partnership (CENRAP), and the Western Regional Air Partnership (WRAP). The RPOs hold their own technical work group sessions throughout the country to make decisions on joint technical work, such as assessments of international transport. The RPOs coordinate technical information on emissions, ambient monitoring, and air quality modeling activities. The RPOs are seeking ways for more involvement by air quality agencies in Canada in their assessment of pollutant formation and transport. (For more information on the U.S. visibility program and RPOs, see www.epa.gov/air/visibility/index.html.)

On February 23-24, 2004, the International Joint Commission's Air Quality Advisory Board held a Workshop on Clean Areas and PSD in Vancouver, British Columbia. The purpose of this workshop was to review the current challenges and possible joint opportunities for clean area management policies in the transboundary region. The workshop examined the PSD and Regional Haze programs in the United States and the KCAC provisions of the Canada-wide Standards for ozone and PM.

Consultation and Notification of Significant Transboundary Air Pollution12

JOINT EFFORTS

The United States and Canada have ongoing notification procedures, established in fall 1994, to identify possible new sources and modifications to existing sources of transboundary air pollution within 62 miles (100 km) of the border. Notifications can occur for new and existing sources located outside of the 62 mile (100 km) region if governments believe that there is the potential for transboundary pollution. Since the last progress report in 2002, the United States has notified Canada of 11 additional sources, for a total of 34. Canada has notified the United States of 11 additional sources as well, for a total of 37.

Transboundary notification information is available on the Internet sites of the two governments at:

Canada:
www.ec.gc.ca/pdb/can_us/canus_applic_e.cfm

United States:
www.epa.gov/ttn/gei/uscadata.html

The United States and Canada report significant continuing progress on joint discussions around the Boundary Dam Power Station (BDPS) near Estevan, Saskatchewan, and Algoma Steel, Inc. in Sault Ste. Marie, Ontario.

SaskPower, the operator of BDPS, has completed the installation of electrostatic precipitators (ESPs) on all units at the power station. The ambient air monitoring network was established prior to installing the ESPs to track changes in air quality before and after installation of this control technology. The latest report of ambient air monitoring data from the network through 2003 showed no exceedances of the applicable ambient air quality standards at any of the sites.

U.S. and Canadian representatives of the federal, state, and provincial governments, the Inter Tribal Council in Michigan, and Algoma Steel continue to operate a comprehensive ambient air monitoring network in the United States and Canada. A report was prepared summarizing all monitoring data collected in the binational area between 2001 and 2003. The draft report was issued in late fall of 2004 and included a brief executive summary for public information and a longer technical report. The Canadian federal and provincial agencies have worked with the steel company to achieve emission reductions. Despite these abatement measures, citizens in Michigan continue to express their concern about the pollution from this plant.

1 The SO2 commitments are listed in the United States-Canada Air Quality Agreement Annex 1:Specific Objectives Concerning Sulfur Dioxide and Nitrogen Oxides, Section 1.Sulfur Dioxide, Part A for the United States and Part B for Canada.

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2 Sulfate deposition is the primary acidifying agent in eastern Canada and the United States.The relative importance of nitrogen deposition is expected to increase ,however ,as sulfur deposition decreases.

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3 One tonne is equal to 1.1 short tons.

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4 Critical loads are the maximum amount of acidifying deposition an ecosystem can tolerate in the long term without being damaged. Canada 's goal for acid rain is to meet its critical loads.

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5 Ontario's target is currently 2015, although the province has proposed and is consulting on advancing the timeline to 2010. Nova Scotia's forecast of 94.5 kilotonnes by 2010 is a reduction target from existing sources and is not meant to be a cap.

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6 The NOx commitments are listed in the United States -Canada Air Quality Agreement Annex 1: Specific Objectives Concerning Sulfur Dioxide and Nitrogen Oxides, Section 2. Nitrogen Oxides, Part A for the United States and Part B for Canada.

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7 The 970,000 tonnes is forecast for 2005 in the NOx/VOC Emission Forecast 90-B in the 1990 NOx/VOC Management Plan. Historical emissions and projections are subject to change as methodologies improve for estimating and forecasting emissions.

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8 The Canadian commitments are listed in the United States -Canada Air Quality Agreement, Annex 1: Specific Objectives Concerning Sulfur Dioxide and Nitrogen Oxides, Section 3, Compliance Monitoring, Part A and B. Utility Units and Other Major Stationary Sources,Subsection 2 and 3 for Canada and for both parties.

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9 The U.S.commitments are listed in the United States -Canada Air Quality Agreement Annex 1: Specific Objectives Concerning Sulfur Dioxide and Nitrogen Oxides, Section 3, Compliance Monitoring, Part A. Utility Units, Subsection 1 for the United States and 3 for both parties.

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10 The commitments are listed in the United States -Canada Air Quality Agreement Article VI and Annex 2: Scientific and Technical Activities and Economic Research.

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11 The commitments are listed in the United States -Canada Air Quality Agreement Annex 1: Specific Objectives Concerning Sulfur Dioxide and Nitrogen Oxides, Section 4. Prevention of Air Quality Deterioration and Visibility Protection, Part A for the United States and Part B for Canada.

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12 The commitments listed in this section come from the United States -Canada Air Quality Agreement, Article V, Assessment, Notification, and Mitigation.

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