Oil SpillsOil Spills

Background InformationBackground Information• Each year, millions of Each year, millions of

gallons of oil are released gallons of oil are released into the environment, into the environment, either accidentally or either accidentally or intentionally.intentionally.– Tanker accidents or Tanker accidents or

“blowouts” “blowouts” – Spills at offshore drilling rigsSpills at offshore drilling rigs– Run-off and dumping waste Run-off and dumping waste

oil from cities and industries.oil from cities and industries.

• In 1979, a huge blowout In 1979, a huge blowout occurred at the Ixtoc I oil well in occurred at the Ixtoc I oil well in the southern Gulf of Mexico. the southern Gulf of Mexico. – Over 184 million gallons of oil Over 184 million gallons of oil

leaked into the environment.leaked into the environment.– Took 8 months to cap the wellTook 8 months to cap the well

As horrendous as that seems, releases from offshore wells during normal operations and

during transportation of the oil add much more oil to the environment than such occasional

accidents.

Accidents happen…Accidents happen…

• Oil tanker accidents account for Oil tanker accidents account for about 10 to 15 percent of the annual about 10 to 15 percent of the annual input of oil into the world’s oceansinput of oil into the world’s oceans

• Leaks at wellsLeaks at wells

• Purging of tanksPurging of tanks

• Seepage from natural sourcesSeepage from natural sources

Oil SpillsOil Spills• Castillow de BellverCastillow de Bellver (1983) caught fire and (1983) caught fire and

relased 78.5 million gallons of ocean off relased 78.5 million gallons of ocean off the coast of Capetown, South Africa the coast of Capetown, South Africa

• Exxon Valdez Exxon Valdez (1989) hit a reef and (1989) hit a reef and released about 11 million gallons of oil into released about 11 million gallons of oil into the Prince William Sound of Alaska. The the Prince William Sound of Alaska. The spill was the largest in U.S. history. Capt. spill was the largest in U.S. history. Capt. Joe Hazelwood, who later admitted to Joe Hazelwood, who later admitted to having had several alcoholic drinks that having had several alcoholic drinks that day, (From Huntington, Long Island). In day, (From Huntington, Long Island). In jail NOW!jail NOW!– More than 33,000 seabirds, 1,000 sea otters, More than 33,000 seabirds, 1,000 sea otters,

100 bald eagles killed.100 bald eagles killed.

How much damage is done?How much damage is done?• The type and amount of The type and amount of

damage from an oil spill damage from an oil spill depend on a number of factors:depend on a number of factors:– Type of oil (crude oil most Type of oil (crude oil most

toxic due to benzene and toxic due to benzene and toluene)toluene)

– Weather conditionsWeather conditions– Types of organisms in the Types of organisms in the

areaarea– Season Season

– Oils spill cleanup is difficult and Oils spill cleanup is difficult and EXPENSIVE. It is very difficult to EXPENSIVE. It is very difficult to save animals who have ingested save animals who have ingested the hydrocarbons into their the hydrocarbons into their digestive tracts, especially aquatic digestive tracts, especially aquatic birds who preen to insulate birds who preen to insulate themselves.themselves.

• On March 24, 1989, an oil tanker On March 24, 1989, an oil tanker struck Bligh Reef in Prince William struck Bligh Reef in Prince William Sound, Alaska, releasing more than Sound, Alaska, releasing more than 200 million liters (11 million) of oil.200 million liters (11 million) of oil.

• The map outlines the oil-spill front as it The map outlines the oil-spill front as it expanded from 1 to 8 days after the expanded from 1 to 8 days after the spill; it was compiled from aerial spill; it was compiled from aerial observations by the National Oceanic observations by the National Oceanic and Atmospheric Administration, and Atmospheric Administration, Exxon, the U.S. Coast Guard, and the Exxon, the U.S. Coast Guard, and the Alaska Department of Environmental Alaska Department of Environmental Conservation. Conservation.

• Bottom sediments studied by the Bottom sediments studied by the USGS more than 7 weeks after the USGS more than 7 weeks after the spill contained no clear evidence of oil spill contained no clear evidence of oil pollution; possible traces of pollution; possible traces of contamination were found near the contamination were found near the south end of the Sound, but the south end of the Sound, but the presence of oil could not be confirmed. presence of oil could not be confirmed.

• Much of the oil was carried onshore by Much of the oil was carried onshore by surface currents and deposited along surface currents and deposited along the beaches. Long-term monitoring is the beaches. Long-term monitoring is needed to assess the effect of the spill needed to assess the effect of the spill on the marine environment. on the marine environment.

So how do we clean it up?So how do we clean it up?• Containment and Containment and

RemovalRemoval• Application of Application of

DispersantsDispersants• BioremediationBioremediation

1.1. Enzymes released by Enzymes released by the microbe break the the microbe break the contaminant down into contaminant down into digestible pieces.digestible pieces.

2.2. The contaminant is The contaminant is consumed as food by consumed as food by the cell.the cell.

3.3. Harmless biological Harmless biological wastes are all that wastes are all that remain of the remain of the contaminant. contaminant.

ReguationsReguations

• In the aftermath of the In the aftermath of the Exxon ValdezExxon Valdez incident, incident, Congress passed the Congress passed the Oil Pollution Act of 1990, , which required the Coast Guard to strengthen which required the Coast Guard to strengthen its regulations on oil tank vessels and oil tank its regulations on oil tank vessels and oil tank owners and operators. Today, tank hulls owners and operators. Today, tank hulls provide better protection against spills provide better protection against spills resulting from a similar accident, and resulting from a similar accident, and communications between vessel captains and communications between vessel captains and vessel traffic centers have improved to make vessel traffic centers have improved to make for safer sailing. for safer sailing.