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AIR QUALITY
Air quality has been improving in the United States as the use of
coal has increased to provide more than half of the nation's electricity.
EPA found the following decrease in emissions at selected monitoring sites
from 1970 to 2000:
- sulfur dioxide(SO2) levels decreased 76 percent
- nitrogen oxide(NOX) levels decreased 58 percent
- particulate matter(PM-10) levels decreased 96 percent
Coal use by electric utilities has risen from 320 million tons in 1970 to 983
million tons in 2000. Emissions of sulfur dioxide
from coal-fired power plants hit a peak of 16.8 million tons in 1975 and
declined to 10.7 million tons in 2000.
These trends are due to several factors, including more effective cleaning
of coal before it leaves the mine; increased use of clean coal technologies,
including improved flue gas
desulfurization systems; the greater use of low sulfur coal; and the blending
of coals with different sulfur contents.
Mining itself causes very little air pollution. Steps are taken by mining
operations to suppress dust from haul roads and the crushing and concentrating
processes. The major expenditures have been made by mineral smelting and
refining operations to control emissions, particularly of SO2.
U.S. Utility Coal Use, Sulfur
Dioxide Emissions
1970-2001
(million short tons)
|
Year
|
Utility Coal Use
|
Emissions/
Coal-Fired Plants
|
| |
|
|
| 1970 |
320 |
15.8 |
| 1975 |
406 |
16.8 |
| 1980 |
569 |
16.1 |
| 1985 |
694 |
15.6 |
| 1995 |
829 |
11.6 |
| 1996 |
875 |
12.2 |
| 1997 |
900 |
12.6 |
| 1998 |
911 |
12.5 |
| 1999 |
894 |
11.8 |
| 2000 |
859 |
10.7 |
| 2001 (p) |
749 |
n/a |
Source: Environmental Protection Agency/Energy Information Administration
(p) = preliminary n/a= not available
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