Canada-United States Air Quality Agreement: Progress Report 2016: Section 2

Ozone annex

Ground-level ozone is a pollutant that forms when emissions of NO_X and VOCs react in the atmosphere in the presence of sunlight. Cars, trucks, buses, engines, industries, power plants, and products such as solvents and paints are among the major man-made sources of ozone-forming emissions. Ground-level ozone, a key component of smog, can cause or exacerbate respiratory illnesses and is especially harmful to young children, the elderly, and those suffering from chronic asthma and/or bronchitis. Exposure to ground-level ozone can damage vegetation, reduce growth, and have other harmful effects on plants and trees. This can make them more susceptible to attack from insects and diseases and reduce their ability to withstand droughts, windstorms, and man-made stresses such as acid rain.

Ambient levels of ozone in the border region

Levels of ambient ozone in the PEMA have a decreasing trend since 1995. Similarly decreasing trends in concentrations are found for both NOX and VOCs. Regulatory and non-regulatory programs designed to meet emissions commitments in the Ozone Annex, as well as programs designed to meet program goals for Canada and the United States individually, have contributed to the reductions in ozone concentrations.

Figure 10 illustrates ozone concentrations in the border region—sites within 500 km (310 miles) of the United States–Canada border. The figure shows that higher ozone levels occur in the Great Lakes and Ohio Valley regions and along the United States’ eastern coast. The lowest values are generally found in western and eastern Canada. Levels are generally higher within and downwind of urban areas (such as in western portions of lower Michigan). The figure illustrates the regional pattern of ozone concentrations. Ozone is depicted in this figure as a 3-year average (2012–2014) of the annual fourth-highest daily maximum 8-hour concentration, in parts per billion (ppb), by volume. Only sites that met data completeness requirements (based upon 75 percent or more of all possible daily values during the EPA-designated ozone monitoring seasons) were used to develop this map.

Figure 11 shows the decreasing trend of ozone concentrations reported as the annual average fourth-highest daily maximum 8-hour ozone concentration for sites within 500 km of the United States–Canada Border for 1995–2014.

Figure 10. Ozone Concentrations along the United States–Canada Border (3-year Average of the Fourth-highest Daily Maximum 8-hour Concentration), 2012–2014

Note: Data are the 2012–2014 averages of annual fourth-highest daily values, where the daily value is the highest running 8-hour average for the day.

Sources: ECCC NAPS Network Canada-wide Database, 2014; EPA Air Quality System Data Mart.

Emissions and emission trends in the PEMA

Table 1 shows 2014 United States and Canadian emissions in the PEMA. In the Canadian PEMA, the sectors that contribute the most to the area’s annual NO_X emissions are on-road and non-road transportation. The predominant sectors that contribute to annual VOC emissions in the Canadian PEMA are solvent utilization processes, non-industrial fuel combustion, and non-road transportation. The sectors that contribute most to NO_X emissions in the United States PEMA are transportation, electric power generation, and industrial sources. Transportation and solvent utilization are the predominant sectors for VOC emissions in the United States PEMA

Table 1.  PEMA Emissions during 2014

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

Source: ECCC and EPA, 2016.

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

Source: ECCC and EPA, 2016.

Figures 14 and 15 show Canadian NO_X and VOC PEMA emission trends for the years 1990 through 2014. For NO_X, each source category shows an overall decrease in emissions with most of the reductions originating from on-road mobile sources, industrial sources, and electric power generation. Similarly, over the same time period, each category of VOC sources shows an overall decrease with most of the reductions coming from non-road mobile sources, on-road mobile sources, and industrial sources. The sharp increase in NO_X emissions for on-road transportation in 2002 is due to a different estimation method beginning with that year.

Figure 14. Canada NO_X Emission Trends in the PEMA Region, 1990–2014

Source: ECCC, 2016

Figure 15. Canada VOC Emission Trends in the PEMA Region, 1990–2014

Source: ECCC, 2016

Figures 16 and 17 show United States PEMA emission trends for 1990 through 2014. There is an overall trend of emission reductions for NO_X and VOCs. The percent decrease in emissions from 1990 to 2014 for NO_X is 51 percent and for VOCs is 38 percent. For NO_X emissions, the on-road and non-road transportation sources account for the greatest portion of the emissions in 2014, followed by fuel combustion for electrical power generation and industrial and non-industrial boilers. The largest NO_X emission reductions from these sources have occurred over the last 12 years. The sharp increase in NO_X emissions for on-road transportation in 2002 is due to a different estimation method beginning with that year.

The greatest contributions of VOC emissions since 2012 are predominantly from solvent utilization, transportation, and industrial sources. Over the period shown in Figure 17, the largest VOC emission reductions have occurred in on-road mobile sources and solvent utilization. While there is an overall decrease in VOC emissions, there have been increases for petroleum and related industries, including oil and gas production, and for prescribed fires. Emission estimation methods and reporting for these sources has also improved significantly in recent years.

Figure 16. United States NO_X Emission Trends in PEMA States, 1990–2014

Source: ECCC, 2016

Figure 17. United States VOC Emission Trends in PEMA States, 1990–2014

Source: ECCC, 2016

Actions to address ozone

Canada and the United States continue to implement programs designed to reduce emissions of NO_X and VOCs. Emissions from power plants and from vehicles remain a focus of these programs.

Canada

Canada has implemented a series of regulations to align Canadian emission standards for vehicles, engines, and fuels with corresponding standards in the United States.

Four regulations concerning on-road and off-road vehicles are in effect and have been subject to various amendments. They include: On-Road Vehicle and Engine Emission Regulations; Off-Road Small Spark-Ignition Emission Regulations; Off-Road Compression-Ignition Engine Emission Regulations; and Marine-Spark Ignition Engine, Vessel, and Off-Road Recreational Vehicle Emission Regulations.

Regulatory initiatives for gasoline include Sulphur in Gasoline Regulations and Benzene in Gasoline Regulations, which have limited the level of sulfur and benzene content in gasoline. In addition, Sulphur in Diesel Fuel Regulations set maximum limits for sulfur in diesel fuels. Sulfur in gasoline impairs the effectiveness of emission control systems and contributes to air pollution. Reducing the sulfur content in gasoline enables advanced emission controls and reduces air pollution.

On July 29, 2015, ECCC published final Regulations Amending the Sulphur in Gasoline Regulations (SiGR Amendments), which introduced lower limits on the sulfur content of gasoline from an average of 30 milligrams per kilogram (mg/kg) to 10 mg/kg, in alignment with the EPA Tier 3 fuel standards. The SiGR Amendments were published with Regulations Amending the On-Road Vehicle and Engine Emission Regulations and Other Regulations Made Under the Canadian Environmental Protection Act, 1999 (ORVEER). The ORVEER Amendments introduce stricter limits on air pollutant emissions from new passenger cars, light-duty trucks, and certain heavy-duty vehicles beginning with the 2017 model year in alignment with the EPA Tier 3 vehicle standards. These two regulatory initiatives work in concert to reduce vehicle air pollutant emissions.

On June 11, 2016, ECCC published proposed amendments to the Off-Road Small Spark ignition Emission Regulations for public comment. These regulations apply to small spark-ignition (SSI) engines found in lawn and garden machines, light-duty industrial machines, and light-duty logging machines. The proposed amendments would incorporate the more stringent EPA Phase 3 exhaust emission standards for machines powered by SSI engines and include new evaporative emission standards for SSI engines that have complete fuel systems attached. The proposed amendments would introduce tighter air pollutant emission standards for the 2018 and later model year SSI engines in Canada.

The federal government continues to address VOC emissions through various regulations. The Tetrachloroethylene (Use in Dry Cleaning and Reporting Requirements) Regulations were published in March 2003 with two goals: (1) reducing the ambient tetrachloroethylene (PERC) concentration in the air to below 0.3 micrograms per cubic meter and (2) reducing PERC use in dry cleaning in Canada to less than 1,600 metric tons per year. Both goals have been achieved. In 2014, dry cleaners reporting under the regulations used less than 600 metric tons (661 short tons) of PERC.

The Solvent Degreasing Regulations, which took effect in July 2003, required a 65 percent reduction in annual consumption of trichloroethylene (TCE) and PERC from affected facilities by 2007. This usage has continued to decline. Under the regulations, ECCC issues annual allowances (consumption units) for use of PERC or TCE to qualifying facilities. Consumption units issued for 2015 represented a reduction of 88 percent for both TCE and PERC relative to the baseline.

ECCC has taken action to reduce VOC emissions from consumer and commercial products. Two regulations, one setting VOC concentration limits for automotive refinishing products and another for architectural coatings, came into effect in 2009. The department is also developing proposed Volatile Organic Compound (VOC) Concentration Limits for Certain Products Regulations, which would establish concentration limits for VOCs in 130 product categories, including personal care, automotive, and household maintenance products; adhesives, adhesive removers, sealants, and caulks; and other miscellaneous products.

The final Code of Practice for the Reduction of Volatile Organic Compound (VOC) Emissions from the Use of Cutback and Emulsified Asphalt was published in the Canada Gazette, Part I on February 25, 2017. The main objective of the Code is to protect the environment and health of Canadians while maintaining road safety by recommending best practices that encourage, when suitable, the use of low VOC-emitting asphalt. It is anticipated that compliance with the Code would result in annual VOC emission reductions of up to 5,000 metric tons from the use of asphalt.

ECCC continues to take action to reduce emissions of smog-forming pollutants. On May 28, 2016, the Code of Practice to Reduce Fugitive Emissions of Total Particulate Matter and Volatile Organic Compounds from the Iron, Steel, and Ilmenite Sectors was published along with a Code of Practice to Reduce Emissions of Fine Particulate Matter (PM_2.5) from the Aluminium Sector.

New ambient air quality standards for PM_2.5 and ground-level ozone were implemented in 2013 under the CEPA 1999 as approved by federal, provincial, and territorial Ministers of the Environment. A review of the 2020 ozone and PM_2.5 standards will be initiated in 2017 and 2018, respectively, to ensure that the standards remain appropriate and reflect the latest scientific information and technological advances. On October 3, 2016, the federal, provincial, and territorial Ministers of the Environment announced new CAAQS for SO  2. In addition, work is underway to establish new, more stringent standards for nitrogen dioxide which is expected to be completed in 2018.

United States

The EPA implemented the NBP under the NO_X State Implementation Plan Call from 2003 to 2008 to reduce ozone season NO_X emissions in eastern states. Starting in 2009, the NO_X annual and ozone season programs under EPA’s CAIR took effect. These programs addressed regional interstate transport of fine particulate matter and ozone by requiring 28 eastern states to make reductions in SO  2 and NO_X emissions that contribute to fine particle and ozone pollution in downwind states. All affected states chose to meet their emission reduction requirements by controlling power plant emissions through the CAIR NO_X annual trading program and the CAIR NO_X ozone season trading program. In addition to the CAIR NO_X ozone season program and the former NBP, prior programs, such as the Ozone Transport Commission’s NO_X Budget Program, and current regional and state NO_X emission control programs (i.e., CSAPR) have contributed significantly to the ozone season NO_X reductions.

From 2013 to 2014, ozone season NO_X emissions from sources in the CAIR NO_X ozone season program decreased by 25,000 short tons (23,000 metric tons) or 5 percent. NO_X ozone season program emissions decreased from 1.5 million short tons (1.4 million metric tons) in 2000 to 450,000 short tons (410,000 metric tons) in 2014, a decrease of 69 percent. CSAPR replaced CAIR on January 1, 2015. For more information, see the CAIR and CSAPR NO_X programs.

In addition to implementing existing United States vehicle, non-road engine, and fuel quality rules to achieve both VOC and NO_X reductions, EPA continues implementation and updating of New Source Performance Standards to achieve VOC and NO_X reductions from new and modified existing sources. Reductions of NO_X emissions are also being achieved through solid waste incineration unit rules and guidelines that impact new and existing incineration units. EPA finalized standards that have significantly reduced NO_X, particulate matter (PM), and VOCs from on-highway light-duty and heavy-duty vehicles.