Environmental Engineering Reference
In-Depth Information
“suffocating” under the pollution caused by the emissions and smog resulting from
the burning of fossil fuels. Sometimes the amount of pollution produced is large
enough to cause regional and even transborder problems, such as the “acid rain”
that originated in the United States but was responsible for the destruction of life in
Canadian lakes. The same has happened to lakes in Scandinavia, owing to indus-
trial activities on the other side of the Baltic Sea. Regional pollution has to be dealt
with at the state or national level and eventually among a number of countries.
Global pollution
is the third category and its most obvious consequences to date
are the destruction of the stratospheric ozone layer (or “shield”) by CFCs (chloro-
fluorocarbons) and the “greenhouse effect.” These problems result from changes in
the composition of the atmosphere and have little to do with national borders. The
causes of such global problems are gases, which can originate from anywhere in
the world. For example, the well-being of people living in Switzerland might ulti-
mately be affected by what takes place in India or China (and vice versa). Global
pollution can only be tackled at the international level.
The classification of environmental problems as local, regional, and global is
somewhat arbitrary because some problems that start as local ones can easily be-
come of regional and even global significance. Oil spills, which are commonplace
but frequently acquire enormous visibility, constitute one example.
Local environmental problems are of three types:
Urban air pollution results mainly from the pollutants emitted by automobiles
and trucks using gasoline and diesel oil. Examples of pollutants include emissions
of sulfur dioxide (SO
2
), carbon monoxide (CO), nitrogen oxides (NO
x
), and partic-
ulate matter (PM) resulting from the burning of fossil fuels, especially oil and coal,
as well as from electricity generation and industry.
Indoor air pollution and emissions of PM and CO result from the use of solid
fuels (biomass and coal) for heating and cooking and toxic emissions from indus-
trial and manufacturing processes.
Pollution of superficial water bodies (rivers, lakes, estuaries) and groundwater
and contamination of soils are caused by leakages of oil by-products, use of fertil-
izers and pesticides in agriculture, leakages from filling stations, and other indus-
trial wastes. Abandoned industrial and mining areas that lack appropriate decom-
missioning operations (cleanup, isolation and storage, recovery) can also contrib-
ute significantly.
