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Today’s Business and Air Quality - Managing Economic Growth and Environmental Protection

Businesses, industries, utilities, and other facilities are critical to today’s modern lifestyle and economy.  They produce our goods and services, they light our homes, and they provide a workplace where we can make our livelihoods.  However, as with other human activities (such as driving our cars), the operation of a business or other facility can have a potential effect on the environment and on human health.  One of the ways in which a facility might impact the environment is by emitting substances into the air.  Here, we would like to give an overview of air pollution, how it is regulated with respect to businesses and other facilities, and how Air & Noise Compliance can assist businesses in minimizing the potential impact they may have on air quality, the environment, and human health.

Pollutants and Standards

To understand the potential effects that a facility might have on air quality, one must first understand the concepts of emissions and concentration.  A facility's emissions is the total amount of a given pollutant that the facility emits over a given time period.  Emissions are frequently described in terms of tons per year (TPY) or pounds per day.  A concentration of a given pollutant is the amount of the pollutant that is found in a “parcel” of air.  Frequently used units of concentration include micrograms per cubic meter (µg/m3) and parts per million (ppm).  As with emissions, the time period is important when evaluating the concentration of a given pollutant.  Pollutant concentrations can be evaluated over many different time periods, including one hour, one day, or one year.  The time period over which a concentration is evaluated is called the averaging period.

The U.S. Environmental Protection Agency (EPA) has set forth standards for a set of pollutants that it refers to as the criteria pollutants.  These standards are referred to as the National Ambient Air Quality Standards (NAAQS) and were promulgated to protect human health and welfare with an adequate margin of safety.  The criteria pollutants include:

• Carbon Monoxide (CO)
• Nitrogen Dioxide (NO2)
• Ozone (O3)
• Lead
• Particulate Matter less than 10 microns aerodynamic diameter (PM10)
• Particulate Matter less than 2.5 microns aerodynamic diameter (PM2.5)
• Sulfur Dioxide (SO2)
For more information about the National Ambient Air Quality Standards (NAAQS):

Geographic areas where air quality complies with the NAAQS are referred to as Attainment Areas.  There are many areas across the country where air quality does not comply with the NAAQS for one or more of the criteria pollutants.  These regions are called Nonattainment Areas. 
For more information about the Nonattainment Areas in New England:
Nonattainment Areas in New England
Most State environmental agencies have their own set of standards that are identical to the NAAQS.  However, some states choose to maintain a different set of standards.  For example, Maine’s sulfur dioxide standards are 57, 230, and 1150 µg/m3 for the annual, 24-hour, and 3-hour averaging periods respectively, making Maine’s sulfur dioxide standards somewhat more stringent than the NAAQS. 

In addition to the criteria pollutants, State environmental agencies may also maintain their own standards for a variety of toxic air pollutants.  New Hampshire, for example, has set forth a set of standards for over 800 toxic air pollutants.  Air & Noise Compliance can assist businesses in determining the toxic air pollutant standards that their facility may be subject to.

Air Quality Regulations and Permitting

The variety of businesses, utilities, and industries in the American economy is limitless.  From electric power plants, to printed circuit board manufacturers, to the neighborhood auto repair shop, each type of business can have its own unique impact on air quality.  Because of this almost unlimited variety, the array of air quality regulations is extremely complex.  Air quality regulations exist at the federal, state, and local level.  Regulations can differ for sources located in nonattainment areas, such as those described above.  Air & Noise Compliance can help businesses determine which regulations are applicable to their particular operation.

Air quality regulations are generally administered through State and Federal air permitting programs.  Air permits are legally enforceable documents that specify the amounts of air pollutants that a facility is allowed to emit into the ambient air.  Permits are basically designed to allow a facility operational flexibility, while at the same time managing that facility's impact on air quality.  Air & Noise Compliance can provide assistance to businesses at each step of the permitting process, including the air quality modeling analysis, which is described below.

Air Quality Impact Modeling

For many facilities, a critical step in the permitting process is the air quality modeling analysis.  These types of analyses use computer models to assess the potential impact of a facility on air quality.  These models, which were developed by the EPA, use a complex set of data inputs to predict a conservatively estimated air quality impact for the facility of interest.  Inputs to these models include information about the facility itself, representative meteorological data, and the topography of the area surrounding the facility.  Using this information, these models predict the expected concentration of the pollutants associated with the operation of the facility in question.  Modeled pollutant concentrations are then compared with the NAAQS and/or applicable toxic air pollutant standards.

If a facility's modeled pollutant concentrations exceed the applicable standards then mitigation measures may be required.  Mitigation measures are taken to ensure that a facility's operation will not have an adverse impact on air quality.  Mitigation measures, if they are necessary, usually become conditions of a facility's air quality permit.  There are a variety of mitigation measures that a facility can take to reduce its impact on air quality, including physical changes and operational changes.  Physical changes include actual modifications to a facility.  For example, increasing the height of a stack or removing any obstructions to its discharge (i.e., rain caps, etc.) can improve the dispersion of air pollutants.  Operational changes can include imposing limits on the amount of time that a pollutant-generating activity takes place, or limiting the amount of fuel that is consumed by boilers and other fuel-burning devices.

Air & Noise Compliance is well versed in the use of EPA air quality models and, when necessary, can help facilities in designing an air quality mitigation plan.  In summary, Air & Noise Compliance can assist facilities and businesses at all phases of the air quality permitting process by performing a defensible analysis, and documenting the results in an accurate, concise, and comprehensive report.  The expertise and service provided by Air & Noise Compliance will ensure that a facility's air permitting needs are met in the most thorough and timely manner possible.