Reducing particulate matter pollution:
Reducing ozone pollution
It is true that commercial vehicles/tractor trailers, old school buses and other large vehicles (heavy-duty vehicles), easily identifiable by plumes of black smoke, often times pollute more per vehicle than the average commuter vehicle. However, the sheer volume of commuter vehicles makes commuter vehicles a threat to air quality that is equally as important.
Commuter vehicles (light duty vehicles) drive 87 percent of the vehicles miles driven on our roads (heavy-duty vehicles drive just 13 percent), making commuter vehicles the overwhelming cause of our traffic congestion problems.
It is easy to underestimate the large amount of air pollution caused by a single automobile. Yet the facts paint a different picture: the average passenger car emits more than 115 lbs. of smog-forming emissions each year (NOx and VOCs). And, the average light truck or SUV emits almost 164 lbs. of smog-forming emissions annually. However, because there are significanlty more passenger vehicles in our most congested areas, reducing the amount of single-occupant vehicles miles driven is one of the best options for improving air pollution and traffic congestion problems.
That does not mean that heavy-duty vehicles are off the hook. Cleaner diesel fuel will be required nationwide in 2007, and cleaner technologies are available that can make diesel engines that use this fuel as clean or even cleaner than gasoline powered vehicles.(Source: U.S. EPA Web Site)
Smog is a term that is used to define unhealthy air that we breathe. This is ground-level ozone and particle pollution. Therefore, particle pollution is smog, but smog does not exclusively refer to particle pollution.
Ground level-ozone is a caustic gas formed when nitrogen oxide and volatile organic compound emissions combine with summertime heat and sunlight to create ozone. Ozone, an unstable molecule made up of three atoms of oxygen, 'oxidizes' with lung lining, triggering asthma attacks, a dry raspy throat and other measures.
Particle pollution is made up of tiny particles and aerosols that are put out into the air. "Soot" is a term that is sometimes used to describe particle pollution. However, this term can be somewhat misleading since the particles in question are very tiny.
Particle pollution comes from some of the same sources as ozone, such as power plants and auto exhaust. However, unlike ozone, particle pollution is a year-round concern.
Any area in nonattainment is violating the national air quality standards or contributing to the violation of at least one of the six pollutants monitored. The designation is based upon EPA's analysis conducted over a three year span through field work and evaluation of monitors at various locations. Once designated, a date is set determining the year the area must meet attainment. To meet attainment, the area must no longer be exceeding the allowable amount of pollution for which it was originally designated in nonattainment.
Conformity refers to the connection between air quality and transportation plans. Conformity occurs when the emissions budget determined by the state and incorporated in the State Implementation Plan (SIP) is met in the TIP. Transportation conformity is required in all nonattainment areas. The transportation plan must show that the implementation of all the projects will not create new air quality violations, increase the frequency or severity of existing violations, or delay attainment in the area. Conformity applies one year after official designation as a nonattainment area. If the transportation plan does not demonstrate conformity by the applicable deadline, the nonattainment area will lapse.
Since 1991, with the passage of the Intermodal Surface Transportation Efficiency Act (ISTEA) and subsequent update of the act in 1998 (The Transportation Equity Act for the 21st Century) known as TEA-21, metropolitan area transportation plans have been required to show conformity with federal Clean Air Act standards. Under the Clean Air Act, every state must submit a State Implementation Plan (SIP) that shows how it will manage and reduce levels of major pollutants that are in violation of federal air quality standards. This includes ground-level ozone and particle pollution. The SIP sets an overall budget for allowable emissions for each pollutant in violation and allocates these emissions for each sector, including transportation.
Thus, transportation plans must show they will contain emissions within a certain level. Failure to do this results in what is known as a "conformity lapse" (meaning that the transportation plan does not conform to its emissions threshold). Any region in a conformity lapse can be prevented from using federal funding for any transportation project that will result in increased emissions; i.e. any road expansion project. Other so-called transportation control measures, however, continue to receive federal funding. This includes all programs funded within the CMAQ program, such as bicycle/pedestrian projects, mass transit, and transportation demand management.
Motorcycles are permitted by federal law to use HOV lanes, even with only one passenger. The rationale behind allowing motorcycles to use HOV lanes is that it is safer to keep two-wheeled vehicles moving than to have them travel in start-and-stop traffic conditions. States can choose to override this provision of federal law, if they determine that safety is at risk. (Source: Federal Highway Administration, Office of Operations)
Hybrids cannot use HOV lanes because they use gasoline and produce fuel vapor emissions. In order to qualify to use the HOV with only a single passenger, a vehicle must meet clean fuel standards as set by the EPA. (Source: Georgia Department of Transportation)
Metro Atlanta has been an ozone nonattainment area since 1979. There are five classifications for ozone nonattainment areas: marginal, moderate, serious, severe, and extreme. The U.S. EPA has recently implemented new standards that measure ozone concentrations by an eight-hour rather than a one-hour time frame. The eight-hour standard has a lower threshold for acceptable ozone concentrations. The implementation of this new standard set the stage for the expansion of the Atlanta nonattainment region and the inclusion of the Macon and Chattanooga metro areas, as studies of the air pollution levels in those areas show that they are violating the new standard. In these metro areas and the state as a whole, significant increases in population and cars have contributed to the increasing pollution levels.
In the newly added counties, pollution sources will be inventoried (how much comes from cars and trucks; how much comes from industry, etc). A plan will then be developed to bring the area into compliance with the ozone standard. While motorists in the expanded areas could be required to have annual car emission inspections, that is not certain. If compliance can be attained without emissions testing (through other smog-reducing activities), emissions testing may not be mandated. Businesses in those areas may also be expected to curb emissions from manufacturing and other industrial practices. Finally, the counties also could come under the jurisdiction of the Georgia Regional Transportation Authority, which has the power to impose transportation changes in bad-air areas, such as redirecting funding from road building to other transit options.
Another reason for the addition of more counties in nonattainment is the more stringent definition by EPA of particulate matter as a pollutant. A new, smaller particle, PM2.5, has been included among the list of pollutants for which an area can be included in nonattainment. All 8-hour ozone nonattainment counties, plus a few more counties throughout the state, were deemed in violation of PM2.5 in December of 2005. (Source: EPA)
The original focus of the monitoring network was on monitoring close to "point" sources (large facilities with high emissions). As air pollution control strategies were successfully implemented and the emissions from large facilities were brought into compliance with air quality regulations, the focus has shifted to pollutants that are more of a regional problem.
Air monitoring stations are primarily used to house continuous instruments that measure "criteria" air pollutants (those that have established National Ambient Air Quality Standards). Monitoring for particulate matter is often accomplished by setting up instrumentation on sampling platform.
Multiple factors are considered when deciding the location of air monitoring station. Sites are selected based on the pollutant or pollutants to be monitored, the population density, proximity to other monitoring stations (including those in other states) and operational efficiency. The U.S. EPA has developed siting requirements for each of the "criteria" air pollutants. These requirements include distance from trees, buildings and roadways, distance from major point sources, and probe height. Other factors include site security and access, availability of electricity and telephone service, aesthetics and local zoning issues, and long term (+10 years) site availability. Unfortunately the ideal monitoring site is virtually impossible to acquire, especially in urban areas. (Source: Deleware Department of Natural Resources & Environmental Control)
Prior to contract/MOA: The sponsor must submit a formal request to the GDOT project manager detailing the changes to be made and the reason for those changes. Any funding difference is the responsibility of the sponsor, and all changes must abide by the goals originally defined in the application and through the CMAQ guidelines. If the changes are approved, the sponsor will be notified by the project manager.
Under contract: Any changes to the work-scope or funding amounts must be approved by GDOT. Significant changes require an amendment or supplement to the existing contract. The amendment will detail the changes to be made and be signed by both GDOT and the project sponsor.
The network year is the year a project is listed in the transportation conformity determination model. The network year usually consists of projects open to traffic within five years.
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