OIL AND RELATED CHEMICALS - Marine Pollution: What Everyone Needs to Know - page 68

in the cleanup. Not all beaches were cleaned, and some
beaches remain oiled today. It is believed that wave action
from winter storms did more to clean the beaches (moving
the oil elsewhere) than all the human effort involved. Exxon
says it spent about $2.1 billion on the cleanup effort. A num-
ber of techniques were attempted. Beach applications of dis-
persants were tried in several locations. Corexit® 7664 was
applied on Ingot Island, followed by a warm water wash.
No significant change in oil cover or the physical state of
the oil was observed as a result of this treatment, however.
High-pressure cold water treatment and hot water treat-
ment involved dozens of people spraying the beaches with
fire hoses. The water, with floating oil, would trickle down
the shore and be trapped within several layers of boom and
either be scooped up, sucked up, or absorbed using special
oil-absorbent materials. Hot water treatment was stopped
after it was found that it seemed to be causing more damage
than the oil by effectively cooking small organisms in the
sand. Mechanical cleanup was attempted on some beaches
using backhoes and other heavy equipment to till the
beaches, exposing the oil underneath which could be washed
out. Many beaches were fertilized to promote growth of
bacteria that metabolize or break down the hydrocarbons.
This type of bioremediation was extensive in 1990, with 378
shoreline segments fertilized to promote bioremediation.
Monitoring of the effectiveness of bioremediation on over 20
beaches determined that oil degradation had been enhanced,
but some disagreement existed over whether bioremedia-
tion was solely, or even largely, responsible. This method of
bioremediation was successful on beaches where the oil was
not too thick. A few solvents and chemical agents were used,
although none extensively. An important observation was
that natural cleaning processes were often very effective at
degrading the oil. It took longer for some sections of shore-
line to recover from invasive cleaning methods (hot water
flushing in particular) than from the oiling itself.