Urban Air Pollution
The transportation sector is responsible for a large majority of air
pollutants in our urban areas, including carbon monoxide and nitrogen
oxides, which form ground-level ozone. Tens of millions of Americans
live in areas not meeting at least one federal air quality standard.
In 1990, Congress passed the Clean Air Act Amendments to combat high
emission levels of carbon monoxide, nitrogen oxides and the creation
of ground-level ozone by petroleum-based transportation fuels. This
Act specifically required the production and distribution of
cleaner-burning gasoline, containing oxygenates such as ethanol, in
America's most polluted cities. ...view middle of the document...
They also require
large-scale, costly clean-up operations. Even more alarming, however,
is that marine oil spills such as the Valdez spill are not nearly as
damaging to the environment as the thousands of smaller spills that
are reported annually. Pipeline spills reported to the U.S. Department
of Transportation average 12 million gallons of petroleum products per
year. The Exxon Valdez Spill, by comparison, spewed out 11 million
gallons. According to the U.S. General Accounting Office, an average
of 16,000 small oil spills seep into waterways each year and estimates
that in recent years more than 46 million gallons have spilled per
Another source of water pollution from gasoline is groundwater
pollution. According to the U.S. Environmental Protection Agency, more
than a quarter of the nation's one million underground gasoline and
oil tanks leak, causing considerable groundwater contamination.
Besides direct oil spills and leakage, secondary water pollution from
petroleum is also a problem. Oil and gas leakage from cars and trucks
is collected on pavement and is carried to streams and lakes whenever
the pavement is wet and water drains across it, causing environmental
damage to aquatic plant and animal life.
Ethanol can replace the most toxic parts of gasoline with a fuel that
quickly biodegrades in water, reducing the threat that gasoline poses
to waterways and groundwater. Ethanol spills or leaks are not an
Bio diesel is also biodegradable in water and is becoming an
attractive alternative to using petroleum diesel for boating to
protect and improve water quality.
Global Climate Change
The U.S. transportation sector is responsible for one third of our
country's carbon dioxide (CO2) emissions. CO2 is considered to be a
greenhouse gas, the build-up of which may lead to global climate
change. These emissions result from combusting fossil fuels, which
releases the carbon content of the fuels into the atmosphere.
Producing and using bio fuels for transportation can help reduce CO2
build up in two important ways: by displacing the use of fossil fuels,
and by recycling the CO2 that is released when it is combusted as
fuel. By using bio fuels instead of fossil fuels, the emissions
resulting from fossil fuel use are avoided, and CO2 content of fossil
fuels is allowed to remain in storage. Further CO2 reductions occur
because the plants and trees that serve as feedstocks for bio fuels
require CO2 to grow, and they absorb what they need from the
atmosphere. Thus, much or all of the CO2 released when biomass is
converted into a bio fuel and burned in automobile engines is
recaptured when new biomass is grown to produce more bio fuels.
Almost half the existing landfills in the U.S. are close to capacity
and are expected to close in the near future, and the rate...