Page 65 - Air Pollution Control Engineering

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Air Quality and Pollution Control 45

Fig. 18. Top 14 VOC/HAP chemicals. (From US EPA.)

9.4.5. Planting Fast-Growing Trees
A third industrial ecology approach is to plant Loblolly pines (Pinus taeda) in areas
with high CO concentrations. These faster-growing trees will respond more to elevated
2
CO levels than will slower-growing hardwoods, because of faster photosynthesis and
2
plant growth. The Loblolly pine is the species most frequently grown for timber produc-
tion in the United States. Its wood has a wide range of uses, such as building material
pulpwood and fuel (33).

9.5. Environmental Laws
As required by the Superfund Amendments and Reauthorization Act (SARA),
Section 313, major US industries began reporting the amounts of toxic chemicals they
9
released into the air, land, and water. In 1987, industries reported that about 2.4×10 lb
of toxic pollutants were released into the air. The US EPA has estimated that air toxics
accounted for between 1600 and 3000 cancer deaths per year, and the average urban
individual lifetime risk of contracting cancer as a result of exposure to air toxics is esti-
mated to be as high as 1 in 1000 persons.
Air toxics emissions from TSDFs have been preliminarily estimated to have a national
population risk of about 140 cancer cases per year. Exposure to these air toxics from
TSDFs has also been estimated to have a maximum individual risk of 2 in 100 persons
contracting cancer.
Figure 18 shows the top 14 VOCs and air toxics, which are referred to as hazardous
air pollutants (HAPs) on a mass emission basis. During the examination of air emission,
the toxicity of each compound and degree of exposure that occur must be considered
(e.g., time and concentration). The most emitted VOC is toluene, but this is less toxic
than benzene, a carcinogen linked to leukemia.
Several major environmental laws have been established to address organic air
emissions. The CAA was created to address major air pollution problems in the United
States. Additional environmental laws include RCRA, amended by the Hazardous and Solid