For the first time in 30 years, Maryland is very close to meeting all federal air quality standards. The Environmental Protection Agency (EPA) has determined that the Baltimore area is meeting the health based federal standard for ground level ozone air pollution. The Washington, DC and the Philadelphia nonattainment areas also have clean data and EPA is expected to make the formal “Clean Data Determination” in 2016. Maryland came into statewide attainment for fine particles in 2012 and fine particle levels continue to drop. EPA introduced a new ozone standard that became effective on October 1, 2015. This more stringent ozone standard will present challenges for Maryland, but we feel we have a plan to address these challenges.
Maryland has adopted effective air pollution controls to address the pollution we generate in the State. Vehicles and fuels are cleaner. Utilities have invested billions of dollars in pollution controls. Toxic emissions from fuels, consumer products and industrial processes have been reduced which has resulted in Maryland’s air quality improving significantly in recent years.
While beneficial weather patterns and cooler summer temperatures over the past several years have certainly played a part in reducing ground level ozone, emission reductions from Maryland’s air quality regulations have lessened the number of days on which Marylanders breathe unhealthy air. Sustained efforts from government, businesses, environmental advocates, scientists, health professionals and many others have brought cleaner air to Maryland and surrounding states. These improvements benefit public health, our quality of life and the economy.
However, there is still work to be done to meet our air quality goals and to attain and maintain a new, stricter ground level ozone standard. The new ozone standard will improve public health protection, particularly for children, the elderly, and people of all ages who have lung diseases such as asthma. Based on 2015 air monitoring data, Maryland is extremely close to meeting the new EPA ozone standard. Fifteen of the State’s eighteen ozone monitors are already below the new ozone standard of 70 parts per billion (ppb). Modeling demonstrates that the Department’s air quality regulations and initiatives will continue to reduce ozone levels and by 2017 the remaining three monitors will be below the new ozone standard as well.
Research shows that pollution from upwind states accounts for up to 70 percent of the ozone levels recorded in Maryland. This air pollution that floats from state to state affects almost every state east of the Mississippi River. On November 16, 2015, EPA proposed an update to the Cross State Air Pollution Rule (CSAPR). This rule, which requires reductions by the summer of 2017, is a critical component of Maryland’s plan to further reduce ozone levels across the State.
Over the past few years, Maryland has played a critical role in bringing together approximately 25 states to see where progress could be made in addressing the issue of transported air pollution. This collaborative effort with Air Directors and Commissioners in many states is looking at additional regional control efforts for power plants, vehicles and other sources of air pollution.
Ground-level ozone and particle pollution are persistent problems in Maryland and other parts of the country. Over the years, Maryland has worked diligently to reduce the emissions that form these harmful pollutants. Ground-level ozone is not emitted directly into the atmosphere, Rather, it is formed by complex chemical processes that require combinations of volatile organic compounds (VOCs), nitrogen oxides (NOx), light and heat. Ground-level ozone is primarily a summer-time problem in Maryland. Over the years, we have had success in reducing the severity and duration of ground-level ozone events. By working with local and regional emissions sources, we have made progress toward achieving the health-based standard.
Maryland experienced the cleanest ozone years on record in 2013, 2014 and 2015 due to the interplay between favorable weather and record low emissions. The decline in pollution levels provides a direct benefit to public health and the natural environment.
To better protect the public health, the U.S. Environmental Protection Agency (EPA) strengthened the National Ambient Air Quality Standard (NAAQS) for ozone in 2015. EPA also strengthened the standard in 1997 and 2008. The chart illustrates Maryland's progress relative to the NAAQS for ozone. For the first time in more than three decades, the metropolitan Baltimore area is meeting the health-based federal standard for ground-level ozone air pollution
Particle pollution is a complex mixture of extremely small particles and liquid droplets. Particle pollution is made up of a number of components, including acids (such as nitrates and sulfates), organic chemicals, metals, and soil or dust particles. Particles are directly emitted and may also be formed by chemical processes in the atmosphere
Maryland had demonstrated attainment of the particle standards since 2008. Installation of control equipment at power plants and other industrial sources as well as switching combustion sources to cleaner fuels has helped to make marked improvements.
Nitrogen dioxide (NO2) is one of a group of highly reactive gasses known as "oxides of nitrogen," or "nitrogen oxides (NOx)." Other nitrogen oxides include nitrous acid and nitric acid. EPA’s National Ambient Air Quality Standard uses NO2 as the indicator for the larger group of nitrogen oxides. NO2 forms quickly from emissions from cars, trucks and buses, power plants, and off-road equipment. In addition to contributing to the formation of ground-level ozone, and fine particle pollution, NO2 is linked with a number of adverse effects on the respiratory system.
Concentrations of NO2 in Maryland are well below the federal standards. Maryland continues to require reductions in NOx as part of a comprehensive strategy to lower ozone levels and to maintain low particle pollution levels.
Carbon monoxide (CO) is a colorless, odorless gas emitted from combustion processes. Nationally and, particularly in urban areas, the majority of CO emissions to ambient air come from mobile sources. CO can cause harmful health effects by reducing oxygen delivery to the body's organs (like the heart and brain) and tissues. At extremely high levels, CO can cause death.
Maryland has maintained compliance with the federal CO standard for many years. Originally, CO was a problem is small sections of Baltimore City. Improvements in vehicle technologies and combustion processes have virtually eliminated CO as an air pollution problem.
Sulfur dioxide (SO2) is one of a group of highly reactive gasses known as “oxides of sulfur.” The largest sources of SO2 emissions are from fossil fuel combustion at power plants (73%) and other industrial facilities (20%). Smaller sources of SO2 emissions include industrial processes such as extracting metal from ore, and the burning of high sulfur containing fuels by locomotives, large ships, and non-road equipment. SO2 is linked with a number of adverse effects on the respiratory system. SO2 also plays a significant role in visibility impairment under the Regional Haze Rule.
Maryland had seen dramatic reductions in SO2 emissions as industrial sources and power plants increasingly use natural gas. Use of low sulfur fuels has also had a significant impact on SO2 emissions.
To learn more about Historical Air Quality Data, please click here
Each year, monitors across the state of Maryland are given a quality of air grade based on the past three seasons. The following animation shows these grades, which are called design values, for ozone across the state of Maryland. Deep purples and reds depict poor ozone air quality with values above 90 ppb. Since 1980 and particularly over the last decade, the design values in Maryland have dropped precipitously so that now these maps depict green colors, which indicate air quality meeting the EPA’s standard.
Notice how the colors are not uniform across the state, and that the change in colors is not the same in all areas. This is due to the social and natural geography of Maryland. Many of the state’s pollution sources which can cause ozone lie along the I-95 corridor from Washington DC, through Baltimore to northeast Maryland. Summer winds blow this pollution to the north and east. Combined with effects along the Chesapeake Bay, this is why areas east of DC and northeast of Baltimore are worse than other areas of the state. These areas also kept colors of brown and red (more polluted) longer. This is because as regional pollution dropped, the effects of local Baltimore and DC pollution remained. Not until the past three years has this signal been eliminated from the states design value calculations.
A new, more protective ozone standard was adopted in 2015 to provide better health protection
Maryland continues to reduce SO2 emissions from power generation
Maryland is now measuring particle pollution levels below the federal standard.
Maryland is on track to meet the 2020 GHG emissions reduction goals
The Regional Greenhouse Gas Initiative is a multi-state effort to reduce greenhouse gas emissions from power generators
In 2015 Maryland adopted more stringent NOx regulations to further clean our air.
The Ambient Air Monitoring Program measures ground-level concentrations of criteria pollutants and air toxics, along with surface and aloft meteorological parameters. The Program also performs quality control, quality assurance, and analysis of the pollutant concentrations that are measured at each of the air monitoring stations located throughout Maryland. It is responsible for Air Quality Index (AQI) reporting and issuing daily air quality forecasts as well as coordination of 3D air-shed photochemical grid and dispersion modeling.
Maryland's Air Quality Planning Program (AQPP) writes state implementation plans and regulations to reduce emissions and achieve the National Ambient Air Quality Standards (NAAQS) for six "criteria" air pollutants: ground-level ozone, particulate matter, lead, carbon monoxide, nitrogen dioxide, and sulfur dioxide. The AQPP also implements federal, regional, local, and state greenhouse gas emissions reduction programs.
Maryland is on pace to meet the greenhouse gas emissions reductions required under State law while benefiting from billions of dollars in economic growth, but continued progress will be needed to minimize the effects of climate change while continuing to create jobs, a new Maryland Department of the Environment report states.
Mobile Sources include a variety of vehicles, engines, and equipment that generate air pollution, and that move or can be moved from place to place. The Mobile Sources Control Program implements programming to reduce motor vehicle related pollution.
The Air Quality Compliance Program works to ensure compliance at stationary sources of air pollution. The Compliance staff conducts inspections, responds to complaints, provides compliance assistance and pursues enforcement actions when necessary.
The Radiological Health Program (RHP) is mandated by Title 8: "Radiation" of the Annotated Code of Maryland, Environment Article, to control the uses of radiation and to protect public health and safety and the environment from inadvertent and unnecessary radiation exposure. This is accomplished through registration and certification of radiation (x-ray) machines, licensing of radioactive materials, inspections, and enforcement actions, where required, to ensure regulatory compliance.
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