CLEAN AIR ACT (1963): The Clean Air Act is designed to control air
pollution on a national level. It requires the Environmental Protection Agency
(EPA) to develop and enforce regulations to protect the general public from
exposure to airborne contaminants that are known to be hazardous to human
health. The act also:- Required comprehensive federal and state regulations for both stationary
(industrial) and mobile sources of air pollution - Expanded federal enforcement authority
- Addressed acid rain, ozone depletion, and toxic air pollution
- Established new auto gasoline reformulation requirements
- Served as the first major environmental law in the United States to
include a provision for citizen lawsuits
NATIONAL ENVIRONMENTAL POLICY ACT (1970): Created the
Environmental Protection Agency (EPA). Also mandated the creation of
Environmental Impact Statements.POLLUTION PREVENTION ACT (1990): Requires industries to reduce
pollution at its source. Reduction can be in terms of volume and/or toxicity.THERMAL POLLUTION
Thermal pollution is the degradation of water quality by any process that
changes ambient water temperature. A common cause of thermal pollution is the
use of water as a coolant by power plants and industrial manufacturers.
Heat Islands
Urban heat islands occur in metropolitan areas that are significantly warmer than
their surroundings. Urban air can be 10°F (6°C) warmer than the surrounding
area. Since warmer air can hold more water vapor, rainfall can be as much as
30% greater downwind of cities when compared with areas upwind.
Reasons for higher urban temperatures (which are usually more pronounced
at night) are:
■ There is more black asphalt and other building surfaces that absorb heat
and reduce the reflectivity of sunlight (reduces the albedo).
■ Additional impervious materials in urban areas reduce the natural cooling