Prevention of Significant Deterioration

Prevention of Significant Deterioration. EPA originally issued regulations for Prevention of Significant Deterioration (PSD) in December 1974 to protect clean air areas. Three air quaUty classes were designated Class I to protect pristine areas. Class II to allow moderate development, and Class III to permit more intensive development. Most areas in the United States were initially designated as Class II. Many large national parks and wildlife areas have been classified as Class I. 

COD Chemical oxygen demand PSD Prevention of significant deterioration... 

Prevention of Significant Deterioration (PSD) Of aU the federal laws placing environmental controls on industiy (and, in particular, on new plants), perhaps the most confusing and restrictive are the limits imposed for the prevention of significant deterioration (PSD) of air quahty. These limits apply to areas of the countiy that are already cleaner than required by ambient air-quality standards. This regula-toiy framework evolved from judicial and administrative ac tion under the 1970 Clean Air Act and subsequently was given full statutoiy foundation by the 1977 Clean Air Act Amendments. 

Sources Subject to Prevention of Significant Deterioration (PSD) Sources subject to PSD regulations (40 CFR, Sec. 52.21, Aug. 7, 1980) are major stationary sources and major modifications located in attainment areas and unclassified areas. A major stationaiy source was defined as any source hsted in Table 25-4 with the potential to emit 100 tons per year or more of any pollutant regulated under the Clean Air Act (CAA) or any other source with the potential to emit 250 tons per year or more of any CAA pollutant. The potential to emit is defined as the maximum capacity to emit the pollutant under apphcable emission standards and permit conditions (after apphcation of any air pollution control equipment) excluding secondaiy emissions. A major modification is defined as any physical or operational change of a major stationaiy source producing a significant net emissions increase of any CAA pollutant (see Table 25-5). 

TABLE 25-3 Prevention of Significant Deterioration (PSD) Air-Quality Increments... 

Does the facility have a prevention of significant deterioration (PSD) permit ... 

It may be desirable to curtail transport of pollution to areas whose air is presently quite clean, even though, after such transport, the air quality of the area would be considerably cleaner than would be required by air quality standards. This concept is called prevention of significant deterioration of the air quality in such areas. It requires definition of how much deterioration can be considered insignificant. 

Stationary monitoring networks are also operated to determine the impact of new sources of emissions. As part of the environmental impact statement and Prevention of Significant Deterioration processes, the projected impact of a new source on existing air quality must be assessed. Air quality monitoring is one means of making this type of assessment. A monitoring network... 

The U.S. Clean Air Amendments of 1977 define two kinds of air quality standards primary standards, levels that will protect health but not necessarily prevent the other adverse effects of air pollution, and secondary standards, levels that will prevent all the other adverse effects of air pollution (Table 22-7). The amendments also define air quality levels that cannot be exceeded in specified geographic areas for "prevention of significant deterioration" (PSD) of the air of those areas. Although they are called "increments" over "baseline air quality" in the law, they are in effect tertiary standards, which are set at lower ambient levels than either the primary or secondary standards (Table 22-8). 

The pollutants, source categories, and affected facilities for which the United States has established New Source Performance Standards are listed in Table 25-1. Certain categories listed in Table 25-1 are subject to U.S. Prevention of Significant Deterioration (of air quality) (PSD) review if their emission potential of a regulated pollutant exceeds 100 tons per year. In... 

On Prevention of Significant Deterioration of Air Quality." National Academy Press, Washington, DC, 1981. 

Emission reduction credits can also be used to offset emissions increases under New Source Review, Prevention of Significant Deterioration, and Base Realignment and Closure. 

Best Available Control Technology (BACT) the control level (or control measures) required for sources subject to the Prevention of Significant Deterioration program (see 40CFR 52.21(b)). 

Prevention of Significant Deterioration (PSD) a program established by the Clean Air Act that limits the amount of additional air pollution that is allowed in Class I and Class II areas. 

Although many limits are implemented at the state level, there are national guidelines that serve as a basis for more specific limits. Sources that are considered major under the CAA are subject to prevention of significant deterioration (PSD) or new source review (NSR). Both PSD and NSR are permit programs for facilities that were constructed or modified after a certain date. 

Prevention of Significant Deterioration (PSD) regulations, 21 584 Preventive maintenance (PM), 15 463, 464-467. See also PM entries for reliability, 26 991, 992 Preventive maintenance inspection, results of, 15 465... 

State Operating Permit Program, Title V (Revised 8/29/94) Prevention of Significant Deterioration (new sonrces in attainment areas) and New Sonrce Review (new sonrces in nonattainment areas) LAER reqnirements (existing sonrce)... 

The guideline recommends air quality modeling techniques that should be applied to State Implementation Plan (SIP) revisions for existing sources and to new source reviews (NSRs), including prevention of significant deterioration (PSD). In addition the guideline serves to identify, for all interested parties, those techniques and databases that EPA considers acceptable. Dispersion models, while uniquely filling... 

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