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The keynote address to the 72nd annual meeting of the Air Pollution Control Association was presented by R.W. Baldwin. His remarks follow:  相似文献   

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Air pollution regulation in the United States has come under repeated attack over the years for a number of reasons. Early in the past decade, prevention of significant deterioration (PSD) legislation, which protects currently clean areas, came into conflict with domestic energy production goals. This paper presents an applied analysis of present and alternative regulations for achievement of PSD air quality goals. A model of the Four Corners region of the Southwest is developed, and several policy alternatives tested in terms of economic efficiency and ability to achieve air quality goals. Alternatives examined include emission fees, marketable emission permits, and technological standards.  相似文献   

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ABSTRACT

The main objective of this study was to investigate the capabilities of the receptor-oriented inverse mode Lagrangian Stochastic Particle Dispersion Model (LSPDM) with the 12-km resolution Mesoscale Model 5 (MM5) wind field input for the assessment of source identification from seven regions impacting two receptors located in the eastern United States. The LSPDM analysis was compared with a standard version of the Hybrid Single-Particle Lagrangian Integrated Trajectory (HYSPLIT) single-particle backward-trajectory analysis using inputs from MM5 and the Eta Data Assimilation System (EDAS) with horizontal grid resolutions of 12 and 80 km, respectively. The analysis included four 7-day summertime events in 2002; residence times in the modeling domain were computed from the inverse LSPDM runs and HYPSLIT-simulated backward trajectories started from receptor-source heights of 100, 500, 1000, 1500, and 3000 m. Statistics were derived using normalized values of LSPDM- and HYSPLIT-predicted residence times versus Community Multiscale Air Quality model-predicted sulfate concentrations used as baseline information. From 40 cases considered, the LSPDM identified first- and second-ranked emission region influences in 37 cases, whereas HYSPLIT-MM5 (HYSPLIT-EDAS) identified the sources in 21 (16) cases. The LSPDM produced a higher overall correlation coefficient (0.89) compared with HYSPLIT (0.55–0.62). The improvement of using the LSPDM is also seen in the overall normalized root mean square error values of 0.17 for LSPDM compared with 0.30–0.32 for HYSPLIT. The HYSPLIT backward trajectories generally tend to underestimate near-receptor sources because of a lack of stochastic dispersion of the backward trajectories and to overestimate distant sources because of a lack of treatment of dispersion. Additionally, the HYSPLIT backward trajectories showed a lack of consistency in the results obtained from different single vertical levels for starting the backward trajectories. To alleviate problems due to selection of a backward-trajectory starting level within a large complex set of 3-dimensional winds, turbulence, and dispersion, results were averaged from all heights, which yielded uniform improvement against all individual cases.

IMPLICATIONS Backward-trajectory analysis is one of the standard procedures for determining the spatial locations of possible emission sources affecting given receptors, and it is frequently used to enhance receptor modeling results. This analysis simplifies some of the relevant processes such as pollutant dispersion, and additional methods have been used to improve receptor-source relationships. A methodology of inverse Lagrangian stochastic particle dispersion modeling was used in this study to complement and improve standard backward-trajectory analysis. The results show that inverse dispersion modeling can identify regional sources of haze in national parks and other regions of interest.  相似文献   

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An addition of additives to fuel oils prior to combustion is one way of reducing combustible contaminant emissions to the outer air. Reported test results show that some additives improve, moderately, the combustive properties of fuel oils. Combustion is also improved but to a lesser degree, in boiler systems that are deficient in operation and design. Being combustible, polynuclear hydrocarbons emissions would be reduced by use of additives. Other types of additives to reduce slagging and inhibit corrosion from combustion of fuel oils are also available. The cost of using additives is low. Improved additives are required, especially ones to better combustion in the deficient boiler systems. These can be found by research and literature surveys. Their effectiveness and nontoxicity would be confirmed by laboratory and field testing.  相似文献   

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The National Ambient Air Quality Monitoring Program is carried out by state and local air pollution control agencies in support of their State Implementation Plans (SIP’s). The current EPA regulations which specify the characteristics of these state monitoring programs are undergoing change as a result of a comprehensive review by an independent work group. These revised regulations, which are described in the paper, are intended to improve the quality, timeliness, and usability of the data generated by the states for all data users. In addition, the revised regulations seek to bring about; (a) national consistency in monitoring site locations through standardized siting procedures; (b) improved network operations by means of a minimum quality assurance program; (c) reduced network inflexibility through an annual network review process; and (d) reduced data reporting through changed data reporting procedures.  相似文献   

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Meteorological factors, pollutant emissions, and geographic regions related to transport of low optical extinction coefficient air to Grand Canyon National Park were examined. Back trajectories were generated by two models, the Atmospheric Transport and Dispersion Model (ATAD) and an approach using the Nested Grid Model output for a Lagrangian particle transport model (NGM/ CAPITA). Meteorological information along the trajectories was analyzed for its relationship to visibility at the Grand Canyon. Case studies considered days with anomalously clean air from the southwest and dirty air from the northwest. Clean air was most frequently from the north and northwest, rarely from the south. Low emissions, high ventilation and washout by precipitation was associated with clean air. All clean days with transport from the Los Angeles area had upper-level low pressure over the region with high ventilation and usually abundant precipitation. The dirtiest days with transport from the northwest were affected by forest fires.  相似文献   

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The Clean Air Act (CAA) Amendments of 1990 was signed into law by President Bush on November 15, 1990. These amendments potentially will have a major impact on virtually every industrial and many commercial facilities throughout the country. The regulations developed to implement this legislation will encompass new approaches to nonattainment, air toxics, accidental releases, acid rain, permits and enforcement. Because of the impact of this legislation the regulations will be implemented over a ten-year period. This paper is an overview of the amendments and recommended proactive strategies for industry.  相似文献   

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The Clean Air Act, Public Law 88-206, was signed into law on December 17, 1963. Among the new provisions was the authorization given to the Secretary of the Department of Health, Education, and Welfare to award grants for the support of State and local air pollution control programs. The Chief, Division of Air Pollution, then requested the Surgeon General’s Air Pollution Training Committee to make recommendations for the most effective way to train the required numbers of people. The Committee called a special three-day meeting at Airlie House with about 30 consultants. Recommendations for training stemming from the meeting included: (1) University-based programs combined with practical experience in control program. (2) Criteria for the selection of trainees. (3) The outline of a model program. These recommendations were submitted to the Chief, Division of Air Pollution and are currently reflected in the activation of one program and a request to the Congress for funds to initiate two more such programs during Fiscal Year 1966.  相似文献   

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The Clean Air Act (CAA) Amendments of 1990 was signed into law by President Bush on November 15, 1990. These amendments potentially will have a major impact on virtually every industrial and many commercial facilities throughout the country. The regulations developed to implement this legislation will encompass new approaches to nonattainment, air toxics, accidental releases, acid rain, permits and enforcement. Because of the impact of this legislation the regulations will be implemented over a ten-year period. This paper is an overview of the amendments and recommended proactive strategies for industry.  相似文献   

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