Exxon Valdez eOil Spill

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  • Exxon Valdez oil spill

    The Exxon Valdez oil spill occurred in Prince WilliamSound, Alaska, on March 24, 1989, when Exxon Valdez,an oil tanker bound for Long Beach, California, struckPrince William Sound's Bligh Reef at 12:04 a.m.[1] lo-cal time and spilled 11,000,000 to 38,000,000 gallons ofcrude oil[2][3] over the next few days. It is considered to beone of the most devastating human-caused environmentaldisasters.[4] The Valdez spill was the largest in US wa-ters until the 2010 Deepwater Horizon oil spill, in termsof volume released.[5] However, Prince William Soundsremote location, accessible only by helicopter, plane, orboat, made government and industry response eortsdicult and severely taxed existing plans for response.The region is a habitat for salmon, sea otters, seals andseabirds. The oil, originally extracted at the Prudhoe Bayoil eld, eventually covered 1,300 miles (2,100 km) ofcoastline,[6] and 11,000 square miles (28,000 km2) ofocean.[7]

    According to ocial reports, the ship was carrying ap-proximately 55 million US gallons (210,000 m3) of oil,of which about 10.1 to 11 million US gallons (240,000to 260,000 bbl; 38,000 to 42,000 m3) were spilledinto the Prince William Sound.[8][9] A gure of 11 mil-lion US gallons (260,000 bbl; 42,000 m3) was a com-monly accepted estimate of the spills volume and hasbeen used by the State of Alaskas Exxon Valdez OilSpill Trustee Council,[6] the National Oceanic and Atmo-spheric Administration and environmental groups such asGreenpeace and the Sierra Club.[5][10][11] Some groups,such as Defenders of Wildlife, dispute the ocial esti-mates, maintaining that the volume of the spill, which wascalculated by subtracting the volume of material removedfrom the vessels tanks after the spill from the volume ofthe original cargo, has been underreported.[12] Alterna-tive calculations, based on the assumption that the o-cial reports underestimated how much seawater had beenforced into the damaged tanks, placed the total at 25 to32 million US gallons (600,000 to 760,000 bbl; 95,000to 121,000 m3).[2]

    1 Identied causesMultiple factors have been identied as contributing tothe incident:

    Exxon Shipping Company failed to supervise themaster and provide a rested and sucient crewfor Exxon Valdez. The NTSB found this was

    During the rst few days of the spill, heavy sheens of oil coveredlarge areas of the surface of Prince William Sound.

    Beginning three days after the vessel grounded, a storm pushedlarge quantities of fresh oil on to the rocky shores of many of thebeaches in the Knight Island chain.[13] In this photograph, pooledblack oil is shown stranded in the rocks.

    widespread throughout the industry, promptinga safety recommendation to Exxon and to theindustry.[14]

    The third mate failed to properly maneuver the ves-sel, possibly due to fatigue or excessive workload.[14]

    Exxon Shipping Company failed to properly main-tain the Raytheon Collision Avoidance System(RAYCAS) radar, which, if functional, would haveindicated to the third mate an impending collisionwith the Bligh Reef by detecting the radar reec-tor, placed on the next rock inland from Bligh Reeffor the purpose of keeping boats on course via radar.This cause has only been identied by Greg Palast(without evidentiary support) and is not present inthe ocial accident report.[15]



    Captain Joseph Hazelwood, who was widely reported tohave been drinking heavily that night, was not at the con-trols when the ship struck the reef. However, as the se-nior ocer, he was in command of the ship even thoughhe was asleep in his bunk. In light of the other ndings,investigative reporter Greg Palast stated in 2008, Forgetthe drunken skipper fable. As to Captain Joe Hazelwood,he was below decks, sleeping o his bender. At the helm,the third mate never would have collided with Bligh Reefhad he looked at his RAYCAS radar. But the radar wasnot turned on. In fact, the tankers radar was left bro-ken and disabled for more than a year before the disaster,and Exxon management knew it. It was [in Exxons view]just too expensive to x and operate. [16] Exxon blamedCaptain Hazelwood for the grounding of the tanker.[15]

    Other factors, according to an MIT course entitled Soft-ware System Safety by Professor Nancy G. Leveson,[17]included:

    1. Tanker crews were not told that the previous practiceof the Coast Guard tracking ships out to Bligh Reefhad ceased.[18]

    2. The oil industry promised, but never installed, state-of-the-art iceberg monitoring equipment.[19]

    3. Exxon Valdezwas sailing outside the normal sea laneto avoid small icebergs thought to be in the area.[19]

    4. The 1989 tanker crew was half the size of the 1977crew, worked 1214 hour shifts, plus overtime. Thecrew was rushing to leave Valdez with a load ofoil.[20]

    5. Coast Guard tanker inspections in Valdez were notdone, and the number of sta was reduced.[20]

    6. Lack of available equipment and personnel ham-pered the spill cleanup.[18]

    This disaster resulted in International Maritime Organi-zation introducing comprehensive marine pollution pre-vention rules (MARPOL) through various conventions.The rules were ratied by member countries and, underInternational Ship Management rules, the ships are beingoperated with a common objective of safer ships andcleaner oceans.In 2009, Exxon Valdez Captain Joseph Hazelwood of-fered a heartfelt apology to the people of Alaska, sug-gesting he had been wrongly blamed for the disaster:The true story is out there for anybody who wants tolook at the facts, but thats not the sexy story and thatsnot the easy story, he said.[21] Yet Hazelwood said hefelt Alaskans always gave him a fair shake.

    Workers using high-pressure, hot-water washing to clean an oiledshoreline

    2 Clean-up and environmental im-pact

    There was use of a dispersant, a surfactant and solventmixture. A private company applied dispersant onMarch24 with a helicopter and dispersant bucket. Becausethere was not enough wave action to mix the dispersantwith the oil in the water, the use of the dispersant wasdiscontinued.[22] One trial explosion was also conductedduring the early stages of the spill to burn the oil, in a re-gion of the spill isolated from the rest by another explo-sion. The test was relatively successful, reducing 113,400liters of oil to 1,134 liters of removable residue, but be-cause of unfavorable weather no additional burning wasattempted.[23][24] The dispersant Corexit 9580 was con-sidered and tried but was not used for shore clean-up duelargely to concerns about toxicity. According to the book-let Shoreline Treatment Techniques published in 1993 bythe Alaska Department of Environmental Conservation,while it eectively assisted in clean-up, It had not beentested, scientic data on its toxicity were either thin orincomplete, and it had operational problems. In addition,public acceptance of a new, widespread chemical treat-ment was lacking. To landowners, shing groups, andconservation organizations, the idea of dumping chemi-cals on hundreds of miles of shorelines that had just beenoiled seemed much too risky - especially when there wereother alternatives. [23][25][25][26]

    According to a report by David Kirby for TakePart, themain component of the Corexit formulation used duringcleanup, 2-butoxyethanol, was identied as one of theagents that caused liver, kidney, lung, nervous system,and blood disorders among cleanup crews in Alaska fol-lowing the 1989 Exxon Valdez spill.Mechanical cleanup was started shortly afterwards usingbooms and skimmers, but the skimmers were not readilyavailable during the rst 24 hours following the spill, andthick oil and kelp tended to clog the equipment.Despitecivilian insistence for a complete clean, only 10% of totaloil was actually completely cleaned.[9] Exxon was widelycriticized for its slow response to cleaning up the disaster

  • 3and John Devens, the mayor of Valdez, has said his com-munity felt betrayed by Exxons inadequate response tothe crisis.[27] More than 11,000 Alaska residents, alongwith some Exxon employees, worked throughout the re-gion to try to restore the environment.

    Clean-up eorts after the 'Exxon Valdez' oil spill

    Because Prince William Sound contained many rockycoves where the oil collected, the decision was made todisplace it with high-pressure hot water. However, thisalso displaced and destroyed the microbial populationson the shoreline; many of these organisms (e.g. plankton)are the basis of the coastal marine food chain, and others(e.g. certain bacteria and fungi) are capable of facilitat-ing the biodegradation of oil. At the time, both scien-tic advice and public pressure was to clean everything,but since then, a much greater understanding of naturaland facilitated remediation processes has developed, duesomewhat in part to the opportunity presented for studyby the Exxon Valdez spill. Despite the extensive cleanupattempts, less than ten percent of the oil was recoveredand a study conducted by NOAA determined that as ofearly 2007 more than 26 thousand U.S. gallons (98 m3)of oil remain in the sandy soil of the contaminated shore-line, declining at a rate of less than 4% per year.[28][29]

    In 1992, Exxon released a video titled Scientists and theAlaska Oil Spill. It was provided to schools with the labelA Video for Students.[30]

    Wildlife was severely aected by the oil spill.

    Both the long-term and short-term eects of the oil spillhave been studied.[31] Immediate eects included thedeaths of 100,000 to as many as 250,000 seabirds, atleast 2,800 sea otters, approximately 12 river otters, 300harbor seals, 247 bald eagles, and 22 orcas, and an un-known number of salmon and herring.[8][32]

    In 2003, fteen years after the spill, a team from theUniversity of North Carolina found that the remainingoil was lasting far l


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