Transcript exxon valdez oil spill

EXXON VALDEZ OIL SPILL
When and What Happened?
 March 24, 1989 the oil tanker Exxon Valdez struck a reef in
Prince William Sound, Alaska creating a hole in the hull
 Estimated 11,000,000 gallons of crude oil spilled across
1,300 miles of coastline
 Captain of ship admitted to having had at least three drinks
before boarding the ship; however, was not charged for it
 $5 billion in punitive damages against Exxon was determined
in 1994; however, that decision has been appealed and
overturned in court and payments have been delayed
 The tanker was renamed and still carries oil around the
world
 The tanker has been barred from ever entering Alaskan
waters again
 Killed an estimated 100,000-400,000 seabirds, 5,000 sea
otters, 200 harbor seals, and countless fish
 Oil smothered plants and animals and affected the pristine
ecological environment
How to recover?
 How does an ecosystem respond to and recover from and
incident like the Exxon Valdez oil spill?
 Cleanup consisted of corralling the oil with booms,
skimming it from the water, soaking it up with absorbent
materials, and dispersing it with chemicals
 Rocky beaches were pressure washed and sand was removed
 First uses of bioremediation used – using natural living
organisms (bacteria) to biodegrade or break down the oil,
enhancing the natural processes
 Some species were able to bounce back and others were not, but it is
unclear as to the reasons
 30 resources or species were categorized in 2002 into the following
categories:
 Not recovered – Harbor seal and Harlequin duck
 Recovery unknown - Cutthroat trout and Rockfish Subtidal
communities
 Recovered - Archaeological resources, Bald eagle, Black oystercatcher,
Common murre, Pink salmon, River otter, Sockeye salmon
 Recovering - Clams, Intertidal communities, Killer whale, Mussels, Sea
otter, Sediments
 Human uses - Commercial fishing, passive use, recreation and tourism
Shoreline treatments
 Pressure washing cleaned oil, but some argued it killed more
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organisms than it saved
Observed that normal degradation processes cleaned oil, in
some areas faster than the invasive cleaning methods used
Cleanup also included manual shoveling, raking and tilling
the beaches; and oily debris pickup
Nearly 100 miles of shoreline was treated with
bioremediation agents
Continual monitoring and data collection was and is ongoing
Economic impacts
 Hundreds of fishermen out of work
 Tourism dropped off significantly
 Because of the cleanup the town of Valdez grew three times
its size, food and clothing stores came to town, and prices
soared
 10,000 workers were employed for the cleanup and other
jobs were plentiful
Ecosystem response
 Toxic substances persist in the Alaskan ecosystem
 Toxicology studies are required to better understand long term
effects from oil spill disasters
 Many indirect effects postponed recovery of many species of wildlife
Lessons learned
 Major improvements in oil spill prevention and response
 Environmental conditions (nutrients, bacteria, oxygen,
temperature, and wave/tidal influence) should be considered
in bioremediation
 Oil spills are known to cause severe and long-term damage
to mangrove and salt marsh ecosystems