Environmental Implications of a Massive Oil Spill and

File: 082696_d50036_004.txt
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Total Pages: 16
respect to carbon monoxide poisoning near the source.  -

If combustion were meomplete, smoke would be denser and smoke
particles might carry incompletely combusted hydrocarbons and other
constituents that might constitute a health hazard. The health hazards and
the characteristics of the smoke vary with the characteristics of the oil, the
size of the spill, and to some extent with the prevailing meteorological
conditions. In strong winds, there is usually a ready supply of oxygen to
Support combustion. In light winds, the heat generated causes convection
and replacement air is drawn in at all sides, but sometimes not sufficiently
rapidly to ensure efficient delivery of oxygen to all parts of the fire. In
both cases, it is the surface area of the fire that determines whether there is
sufficient oxygen available to ensure more complete combustion.

Considerable relevant information has been generated in studies of oil
refmery and storage facility fires. Laboratory and small-scale burning
studies over the last 15 years have attempted to characterize combustion
by-products under a variety of conditions, however very little information
specific to Arabian crude oils has been reported. Most knowledge of the
effects of large fires comes from investigations of large forest fires. In
practice, the concentration of smoke particles is likely to be the dominant
source of health concern, especially for civilian populations.

Ash fallout from the plume might well be cause for concern in the
immediate vicinity of the fire. The governing consideration is that the
largest particles would fall out first. These could~carry~unburnt
hydrocarbons and other combustion products with the in, and some of these
compounds could be hazardous to human health as well as to animals living
in the area of deposition. The magnitude of this problem would be
controlled by factors that cannot be predicted; such as the size and duration
of the fire, the completeness of the combustion, and weather conditions at
the tirne. However, serious depositional hazards would no doubt be limited
to the immediate region, up to a hundred miles or so from the source.


2. How large an area would be affected by the smoke plume?

Depending on how much oil is burned, the plume should rise initially up to
3000 to 5000 feet. Within the first few miles, the smoke plume would be
dense and black. At tens of miles, the plume would be strongly visible. At
hundreds of miles, the plume would be diffuse but visible. At thousands of
miles it would be barel~ detectable.


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