Point source pollution

In comparison with other studies, which reflect either diffusive pollution or sampling sites located relatively far from the pollution point source, the sampling... 

Marine mammals collected near heavily urbanized or industrialized areas or near zinc pollution point sources usually had elevated zinc concentrations when compared to individuals of the same species and of similar age from relatively pristine environments (Eisler 1984). Zinc concentrations in tissues of the ringed seal (Phoca hispida) were essentially the same in animals near a lead-zinc mine and in those of a distant reference site, although lead and selenium burdens were elevated in the vicinity... 

Black, J.J. Movement and identification of a creosote-derived PAH complex below a river pollution point source. Arch. Environ. Contam. Toxicol, 11(2) 161-166, 1982. 

The majority of AOTs can be applied to the remediation and detoxification of low or medium volumes of waters. Ground, surface, and wastewater can be treated, giving rise to the destruction or transformation of hazardous or refractory pollutants. Point sources of toxic pollutants such as pesticides, heavy metals and others can be treated in small-scale mobile treatment units, easy to install in industrial plants. The methods can be used alone or combined with other AOTs or with conventional methods. The use of modular units allows the selection of the best technology or combination of technologies to treat a specific wastewater. AOTs can also be applied to pollutants in the air and soil, and they may even allow disinfection or sterilization of bacteria, viruses, and other microorganisms. 

When environmental contamination occurs, it is the result of either point-source or non-point-source pollution. Point-source pollution comes from a specific, identifiable place (point). A pesticide spill that moves into a storm sewer is an example of point-source pollution. Non-point-source pollution comes from a wide area. The movement of pesticides into streams after broadcast applications is an example of non-point-source pollution. 

Sources of pollution vary from smaU-scale businesses, such as dry cleaners and gas stations, to very large-scale operations, such as power plants and petrochemical facilities. The effluent streams of industry are particularly noticeable because of their large volumes [1]. Sources include both point-source and non-point-source pollution. Point-source pollution can be traced directly to single outlet points, such as a pipe releasing into a waterway. Non-point-source pollutants, on the other hand, such as agricultural run-off, cannot be traced to a single definite source. The emissions from both span a wide range of gas, liquid, and solid compounds. 

Point sources are pollution sites that have a definite identifiable source. Discharges from a chemical industry or raw sewage from wastewater treatment plants are common examples of point-source pollution. Point sources are easy to identify, control, and regulate. The Environmental Protection Agency (EPA) is the governmental agency that regulates point sources. 

Point and Nonpoint Source Pollution. Point source pollution comes from a discrete, easily identifiable... 

Existing methods for monitoring the transport of gases were inadequate for studying aerosols. To solve the problem, qualitative and quantitative information were needed to determine the sources of pollutants and their net contribution to the total dry deposition at a given location. Eventually the methods developed in this study could be used to evaluate models that estimate the contributions of point sources of pollution to the level of pollution at designated locations. 

Part 403 general pretreatment regulations for existing and new sources of pollution Part 411 cement manufacturing point source category Part 413 electroplating point source category... 

Analysis of Clean Water Act Effluent Guidelines Pollutants. Summary of the Chemicals Regulated by Industrial Point Source Category U.S. EPA, Washiagton, D.C., 40 CFR Parts 400-475, 1991. 

Fig. 5. Diffusion of pollutants from a point source. PoUutant concentrations have separate Gaussian distributions in both the horizontal (j) and vertical directions. The spread is parameterized by the standard deviations ( O ) which are related to the diffusivity (fQ.

Bubble Policy The bubble concept introduced under PSD provisions of the Clean Air Act Amendments of 1977 was formally proposed as EPA policy on Jan. 18, 1979, the final policy statement being issued on Dec. 11, 1979. The bubble pohcy allows a company to find the most efficient way to control a plant s emissions as a whole rather than by meeting individual point-source requirements. If it is found less expensive to tighten control of a pollutant at one point and relax controls at another, this woiild be possible as long as the total pollution from the plant woiild not exceed the sum of the current hmits on individual point sources of pollution in the plant. Properly apphed, this approach would promote greater economic efficiency and increased technological innovation. 

It is also clear that it is difficult to relate cause and effect to any specific chemical since, with the exception of point source effluents, many waterways contain a multitude of chemicals, of which the active endocrine disruptor may not be that which has been measured in the water or tissue. For such reasons, many studies have used in vitro experiments in which isolated tissue, either from a control animal or one captured in a polluted water system, is exposed to a single pollutant in the laboratory. Such experiments have shown significant disruption to testicular activity by a wide range of xenobiotics, including cadmium, lindane, DDT, cythion, hexadrin and PCBs. ... 

The third category for interactions is high dose (III). The effects produced by this level of interaction can be seen by the casual observer. The result of high-dose exposure is destruction or severe injury of the forest system. High-dose conditions are almost always associated with point source emissions. The pollutants most often involved are SO2 and hydrogen fluoride. Historically, the most harmful sources of pollution for surrounding forest ecosystems have been smelters and aluminum reduction plants. 

The initial direction of transport of pollutants from their source is determined by the wind direction at the source. Air pollutant concentrations from point sources are probably more sensitive to wind direction than any other parameter. If the wind is blowing directly toward a receptor (a location receiving transported pollutants), a shift in direction of as little as 5° (the approximate accuracy of a wind direction measurement) causes concentrations at the receptor to drop about 10% under unstable conditions, about 50% under neutral conditions, and about 90% under stable conditions. The direction of plume transport is very important in source impact assessment where there are sensitive receptors or two or more sources and in trying to assess the performance of a model through comparison of measured air quality with model estimates. 

Gaussian techniques, discussed in Chapter 19, are reasonable for estimates of concentrations of nonreative pollutants within 20 km of point sources. It is preferable to utilize on-site wind fluctuation measurements to estimate the horizontal and vertical spreading of a pollutant plume released from a point source. 

The behavior of these pollution roses is intuitively plausible, because considerable hydrocarbon emissions come from motor vehicles which are operated in both winter and summer and travel throughout the urban area. On the other hand, sulfur dioxide is released largely from the burning of coal and fuel oil. Space heating emissions are high in winter and low in summer. The SO2 emissions in summer are probably due to only a few point sources, such as power plants, and result in low average concentrations from each direction as well as large directional variability. 

Examples of point sources of air pollution, general control methods, and pollution prevention and energy saving practices... 

In this chapter we focus our attention on some of the point sources of air emissions within different types of plant operations, along with the methods of abatement. Although we do not make direct comparisons between prevention and control methodologies until Chapter 6, the reader should gain an appreciation for the simplicity of applying pollution prevention as opposed to incorporating engineering controls in many situations. 

All efforts to prevent or correct LAQ problems should include an effort to identify and control pollutant sources. Source control is generally the most cost effective approach to mitigating LAQ problems in which point sources of contaminants can be identified. In the case of a strong source, source control may be the only solution that will work. The following are categories and examples of source control ... 

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