The 1990 amendments to the federal Clean Air Act require states to address a number of air quality issues. These include:
- National Ambient Air Quality Standards, which are health-based standards applied to six "criteria pollutants": carbon monoxide, lead, nitrogen oxides, ozone, particulates, and sulfur oxides.
- National Emission Standards for Hazardous Air Pollutants, also health-based, that apply to "hazardous" pollutants not covered by the air quality standards: asbestos, benzene, beryllium, inorganic arsenic, mercury, radionuclides and vinyl chloride.
- New Source Performance Standards, technology-based minimum standards that limit emissions of regulated pollutants from newly built plants and some existing plants that undergo modification.
- Pollution reduction offsets are required for major new facilities and modifications to existing facilities emitting volatile organic compounds or VOCs and nitrogen oxides or NOx in the Northern Virginia, Richmond and Hampton Roads areas. These offsets are a means of abating existing pollution levels by requiring a greater than 1-to-1 offset ratio. Offsets may include emissions trading within the same non-attainment area. A new or modified facility acquires offset credits by reducing emissions from other existing facilities in the area.
- Phase-out of stratospheric ozone depleting chemicals: CFCs, halons, carbon tetrachloride, methyl chloroform and hydrofluorocarbons.
- Reduction in hazardous pollutant emissions within 10 years. Sources that are identified as subject to Maximum Achievable Control Technology or MACT (major new and existing sources} will be expected to reduce 90 percent or more.
- Decrease in urban smog by reducing emissions from small businesses, as well as large factories and vehicles.
- Reduction of annual sulfur dioxide and nitrogen oxide emissions from electric utilities by 10 million tons in two stages by the year 2000.
Under the air quality standard program, geographic areas that violate the standard for one or more criteria pollutants are called "nonattainment areas." In nonattainment areas, new plants and major modifications must meet the Lowest Achievable Emission Rate or LAER, defined as the most stringent emissions limitation derived for that type of plant. Also, to avoid increasing the total amount of a criteria pollutant in a nonattainment area, a new or expanding business must offset whatever emissions it intends to emit. For volatile organic compounds and nitrogen oxides, the offsetting ratio must be greater than 1-to-1, depending on the severity classification of the non-attainment area.
To be classified an ozone nonattainment area, an air quality control region must exceed the air quality standard at a single monitor four times in a three-year period. The nonattainment areas in the state are Northern Virginia and the upper elevations of Whitetop Mountain in Smyth County.
Prevention of Significant Deterioration Areas
A prevention of significant deterioration area or PSD, is a geographic area designated "attainment" or "unclassifiable" for any pollutant for which an air quality standard exists. Sources of air pollution in a PSD area are regulated to keep the air quality good as new businesses come into the area. Permit and control requirements vary with the classification of the area.
- Class I areas -- primarily national parks and wilderness areas. Few pollution impacts are allowed, and some types of nearby industrial development are severely restricted.
- Class II areas -- limited amounts of new emissions are allowed.
- Class III areas -- greater amount of new emissions are permitted. No Class III areas are currently designated in Virginia.
Virginia currently has two Class I PSD areas: Shenandoah National Park and James River Face Wilderness. The remainder of the state is designated Class II. Facilities affecting both Class I and Class II areas that have the potential to emit 250 tons of a pollutant, or 100 tons for a specific list of 28 source categories, will need to meet more stringent permitting requirements and apply Best Available Control Technology or BACT.
Virginia Air Pollution Control Law
Through the Virginia Air Pollution Control Law, the General Assembly has empowered the State Air Pollution Control Board to administer the shared federal programs and to adopt additional regulations that are considered beneficial to the health and well-being of the citizens of the Commonwealth.
State regulations include several issues not addressed by federal law. The regulations limit opacity caused by air pollutants, except during specified periods Sources of dust must take "reasonable precautions" to prevent particulate matter from becoming airborne. The regulations also prohibit odorous emissions that are "objectionable to individuals of ordinary sensibility."
The Air Toxics Inventory Program was established by the Air Board in 1985. The Clean Air Act amendments of 1990 address the same substances monitored by this program. Under the program, the board regulates ambient concentrations of 189 priority pollutants. Sources may be required to provide emissions data on toxics emissions. In addition, because DEQ has jurisdiction over all pollutants, it may request information on any emission of concern in a permit application. During the 1990s, the EPA will be developing more specific emissions standards and requirements for control technology (MACT standards) for 189 toxic pollutants.
The air Operating Permit Program is a relatively new concept in Virginia. Its goal is to place all air permitting requirements applicable to a given facility into a single document. The permit should be renewed at five-year intervals to reflect changing requirements attributable to both facility needs and changing regulatory requirements.
The Commonwealth established its state operating permit program in 1991 in response to the anticipated need for a federally mandated program. Now that the federal government has mandated an operating permit program and set out requirements for all states to meet, Virginia and other states are making use of their programs to ease industry's transition to the federal operating permit program, known as the Title V Operating Permit Program.
Essential operating permit concepts include:
- Potential to emit. Potential to emit is the maximum physical and operational capacity of a source, or emission unit, to emit any air pollutant. This potential is predicated on year-round, day-and-night operation, but it also takes into account federally enforceable restrictions and controls on the facility, such as those found in a permit. It does not take into account voluntary limits on operation, or state controls.
- Applicable requirements. Neither the state nor the federal operating permit program contains extensive substantive requirements of its own. Both serve as vehicles for identifying all requirements applicable to the source. These requirements can include, but are not limited to, compliance, record-keeping, reporting, emission controls, emission limits, work practices, operating hours, and other matters stemming from federal and state air laws and regulations, and permits issued to allow construction or modification of the facility.
- Synthetic minors and potential to emit: use of the state program. A source can avoid the requirement to apply for a Title V permit if it can qualify for a state operating permit that keeps its potential to emit below the thresholds in the Title V major source definition. This is known as a "synthetic minor." Similarly, an existing source may seek a modification to its operation and agree to take an emissions limit that keeps the whole source below the major threshold. The modification permit also serves to make the source a "synthetic minor." It will not be a Title V major source as long as these limits are enforceable through the state operating or modified source permits.