Thursday, May 16, 2019
Exxon Mobil and Environment
Author Login cyclopaedia of Earth Search Top of Form picpic Bottom of Form Earthportal Earthnews cyclopedia of Earth Forum EoE Pages o Home o About the EoE o Editorial Board o International Advisory Board o FAQs o EoE for Educators o Contri thoe to the EoE o Support the EoE o Contact the EoE o Find Us Here o RSS o Reviews o Awards and Honors pic Solutions Journal pic run the EoE o Titles (A-Z) o Author o Topics o Topic Editor o depicted object Partners o Content Sources o eBooks o Environmental Classics o Collections pic pic pic Exxon Valdez crude anoint spill Table of Contents 1 Introduction 2 Events leading up to the spill 3 The behavior of the crude anoint 4 Countermeasures and mitigation 4. 1 Control of the c everywhere spill at sea 4. 2 Shoreline interposition 5 frugal clashings 6 How often sentences embrocate catch ones breaths? 7 Eco trunk solvent to the spill 7. 1 Acute death rate 7. 2 Long-term impacts 7. 3 State of recoery 8 Legal re sponsibility of ExxonMobil 8. 1 shepherds crook settlement 8. 1. 1 Plea Agreement 8. 1. Criminal Restitution 8. 2 Civil Settlement 9 The receipt of ExxonMobil 10 Lessons learned from the spill 11 Further Reading pic pic Contributing Author Cutler J.Cleveland ( other(a) binds) Content Source issue maritime and Atmospheric Administration (other articles) Article Topics Pollution and Energy This article has been reviewed and canonic by the following Topic Editor Peter Saundry (other articles) Last Up pictured sublime 26, 2008 pic Introduction On jar against 24, 1989, the tanker Exxon Valdez, en route from Valdez, Al holda to Los Angeles, California, ran aground on Bligh Reef in Prince William vowelize, Alaska. The vessel was traveling remote normal exile lanes in an attempt to avoid ice.Within six hours of the grounding, the Exxon Valdez spil direct approximately 10. 9 zillion g exclusivelyons of its 53 zillion gallon cargo of Prudhoe talk crude embrocate. Eight of the eleven tanks on board were damaged. The crude would eventually impact over 1,century miles of non-continuous coastline in Alaska, making the Exxon Valdez the largest oil spill to date in U. S. waters. The response to the Exxon Valdez involved more personnel and equipment over a longsighteder period of time than did any other spill in U. S. history.Logistical problems in providing fuel, meals, berthing, response equipment, waste management and other resources were one of the largest challenges to response management. At the top of the response, more than 11,000 personnel, 1,400 vessels and 85 aircraft were involved in the cleanup. pic pic The Exxon Valdez aground on Bligh Reef. (Source NOAA) Shoreline cleanup began in April of 1989 and go along until September of 1989 for the first form of the response. The response effort continued in 990 and 1991 with cleanup in the spend months, and limited shoreline monitoring in the winter months. Fate and do monitoring by e reconcile and federal agencies atomic number 18 ongoing. The images that the world saw on television and descriptions they heard on the radio that spring were of intemperately oiled shorelines, dead and dying wildlife, and thou sands of workers mobilized to clean b for each onees. These images reflected what many people felt was a horrific environmental insult to a relatively pristine, ecologically important atomic number 18a that was home to many species of wildlife endangered elsewhere.In the weeks and months that followed, the oil spread over a wide bea in Prince William solidly and beyond, resulting in an unprecedented response and cleanupin fact, the largest oil spill cleanup ever mobilized. Many local, state, federal, and individual(a) agencies and groups took part in the effort. Even today, scientists continue to workplace the alter shorelines to understand how an ecosystem like Prince William enunciate responds to, and recovers from, an incident like the Exxon Valdez oil spill. Events leading up to the spillThe Exxon Valdez departed from the Trans Alaska Pipeline terminal at 912 pm, manifest 23, 1989. William Murphy, an unspoiled ships pilot hired to lock the 986-foot vessel through the Valdez Narrows, was in control of the wheelhouse. At his side was the sea captain of the vessel, Joe Hazelwood. steerer Harry Claar was steering. After passing through Valdez Narrows, pilot Murphy left the vessel and lord Hazelwood took over the wheelhouse. The Exxon Valdez encountered icebergs in the shipping lanes and Captain Hazelwood ordered Claar to stimulate the Exxon Valdez out of the shipping lanes to go around the ice.He then handed over control of the wheelhouse to Third Mate Gregory Cousins with precise instructions to turn back into the shipping lanes when the tanker reached a certain point. At that time, Claar was re sided by Helmsman Robert Kagan. For reasons that remain unclear, Cousins and Kagan failed to make the turn back into the shipping lanes and the ship ran aground on Bligh Reef at 1204 a. m. , March 24, 1989. Captain Hazelwood was in his quarters at the time.The field of study Transportation gumshoe Board investigated the accident and determined five probable causes of the grounding (1) The third mate failed to properly maneuver the vessel, possibly due to fatigue and excessive workload (2) the master failed to provide a proper sailing watch, possibly due to impairment from alcohol (3) Exxon Shipping Company failed to supervise the master and provide a rested and sufficient crew for the Exxon Valdez (4) the U. S. semivowel Guard failed to provide an effective vessel traffic system and (5) effective pilot and escort run were lacking.The behavior of the oil pic pic The oil slick (blue areas) eventually blanket(a) 470 miles souwest from Bligh Reef. The spill area eventually coreed 11,000 square miles. (Source Exxon Valdez Oil freeing legal guardian Council) Prudhoe Bay crude oil has an API gra vity of 27. 0, and a pour point of 0 degrees Celcius. The bulk of the oil spilled from the Exxon Valdez was released inside 6 hours of the ships grounding. The ordinary trend of the oil was south and west from the point of origin. For the first few days after the spill, most of the oil was in a large c erstwhilentrated patch scraggy Bligh Island.On March 26, a storm, which generated winds of over 70 mph in Prince William belong, weather much of the oil, changing it into mousse and tarballs, and distributed it over a large area. By March 30, the oil ex track downed 90 miles from the spill site. Ultimately, from Bligh Reef, the spill stretched 470 miles southwest to the village of Chignik on the Alaska Peninsula. Approximately 1,300 miles of shoreline were oiled. 200 miles were heavily or moderately oiled (obvious impact) 1,100 miles were lightly or very lightly oiled (light sheen or occasional tarballs). The spill region contains more than 9,000 miles of shoreline.In sum total to the storm of March 26, the spill occurred at a time of year when the spring tidal fluctuations were most 18 feet. This tended to deposit the oil onto shorelines in a higher place the normal regularise of wrap action. The diversity in shoreline types in the affected areas led to varied oiling conditions. In many cases, oil was present on sheer carry faces making access and cleanup difficult, or stiry beaches with grain size anywhere from coarse sand to boulders, where the oil could percolate to a sub- go up level. The spill affected 2 sheltered and exposed (to last drift/weather action) shorelines.Once oil landed on a shoreline it could be floated off at the next high tide, carried to and deposited in a different location, making the tracking of oil migration and shoreline impact very difficult. This migration ended by mid-summertime 1989, and the stay cleanup dealt with oiled shorelines, rather than oil in the water. Cleanup operations continued during the summer month s of 1990 and 1991. By 1990, step to the fore oil, where it existed, had become significantly brave. Sub-surface oil, on the other hand, was in many cases much little wea in that respectd and soundless in a liquid state. The liquid sub-surface oil could give off a sheen when disturbed.Cleanup in 1991 concentrated on the remaining cut back quantities of surface and sub-surface oil. Countermeasures and Mitigation Control of the oil spill at sea The Alyeska Pipeline Service Company was immediately nonified of the incident and sent a tug to the site to assist in stabilizing the vessel. At the time of the incident, the Alyeska spill response thrust ahead was out of service being re-outfitted. It arrived on scene by 1500 on 24 March. Alyeska was overwhelmed by the magnitude of the incident by March 25, Exxon had assumed full responsibility for the spill and cleanup effort. pic pic The Exxon Valdez surrounded by a containment gold rush. Source Exxon Valdez Oil firing regent Counc il) Deployment of boom around the vessel was complete inside 35 hours of the grounding. Exxon conducted successful dispersant scrutiny applications on March 25 and 26 and was granted permission on March 26 to move over dispersants to the oil slick. Due to the large storm that began the evening of March 26, much of the oil turned into mousse. As dispersants arent generally able to dissipate oil in the form of mousse, it was no longer practical to use dispersants on floating oil during this response. On the evening of March 25, a test in-situ burn of oil on water was conducted.Approximately 15,000 to 30,000 gallons of oil were collect using 3M discharge Boom towed behind two sportfishing vessels in a U-shaped configuration, and ignited. The oil burned for a total of 75 minutes and was reduced to approximately 300 gallons of residue that could be collected easily. It was forecastd that the efficiency of this test burn was 98 percent or go bad. Again, continued in-situ burning was not possible because of the change over in the oils state after the storm of March 26. Five dispersant trials took place between March 25 and March 28, but by March 29 the Regional Response Team (RRT) decided that dispersants were no longer feasible.Because there was not enough equipment to protect all the shorelines that could be impacted, Federal, state and local agencies collaborated to engraft shoreline protection priorities. The agencies decided that fish hatcheries and salmon streams had the highest antecedence accordingly, containment booms were deployed to protect these areas. Five fish hatcheries in Prince William speech sound and two in the Gulf of Alaska were boomed, with the largest add together of boom deployed at the Sawmill Bay hatchery in Prince William Sound.At the height of containment efforts, it is estimated that a total of 100 miles of boom was deployed. Almost all the types of boom available on the grocery store were utilize and tested during the spill r esponse. Due to the size of the spill, it was necessary to employ inexperienced workers to deploy and tend booms, and this led to virtually boom being incorrectly used or handled, and nearwhattimes damaged. Some boom sank because of improper deployment, infrequent tending, or leakage and/or inadequacy in the buoyancy system. Other problems include fabric tears in boom due to debris, and tearing at anchorage points from wave action.In whatever cases, ballast chains were ripped off during boom convalescence if the boom was lifted by the chain. One estimate suggests that 50 percent of the damage to larger boom came during boom recovery. For self-inflating booms, it was important to keep the inflation valves above the water during deployment so that the boom did not become filled with water and have to be replaced. transmitting aerial surveillance was used to direct the deployment of booms and navy mans for open water oil recovery. Visual overflight observations as intimately as ultraviolet/infrared (UV/IR) brush ups were used by the USCG and Exxon to track the floating oil.Satellite imagery was also tested as a method to track oil but was not very useful because of the infrequency of satellite passes over Prince William Sound (every 7 to 8 days), cloud cover, and spacey turn around time for results. The special means of open water oil recovery was with sailors. In general, most skimmers became less effective once the oil had spread, emulsified and mixed with debris. To save time, it was most practical to keep skimmer offloading equipment and oil storage barges near the skimmers. The most used skimmers during the response were the Marco sorbent lifting- crash skimmers that were supplied by the U.S. Navy. Once oil became viscous, the sorbent part of the skimmer was removed and the conveyor belt alone was sufficient to pull the oil up the ramp. The pump that came with the skimmer had difficulty offloading viscous oil, so that other vacuum equipment was used to unload the collected oil. The Marco skimmers were generally not used close to shore because they draw between three and four feet. In general, the paddle belt and rope mop skimmers were the most useful for recovery of oil from the shoreline. The skimmers were placed on self-propelled barges with a shallow draft.Sorbents were used to recover oil in cases where mechanical means were less practical. The drawback to sorbents was that they were labor intensifier and generated additional solid waste. Sorbent boom was used to collect sheen between primary and secondary winding layers of offshore boom, and to collect sheen released from the beach during tidal flooding. Pompoms were useful for picking up small amounts of weathered oil. Towing of sorbent boom in a zigzag or circular fashion behind a boat was used to collect oil and was more efficient than towing the boom in a bully line.Sorbent booms made of rolled pads were more effective than booms made of individual particles bec ause these absorbed less water and were stronger, and did not break into many small particles if they came apart. Early on in the response, storage space for recovered oil was in hapless supply. To combat the storage space problem, water was decanted from skimmers or tanks into a boomed area in the lead offloading. As a result, the remaining viscous oil mixture was difficult to offload, the process sometimes taking up to 6 to 8 hours. High- message skimmer offloading pumps, in particular grain pumps, were the most useful in transferring viscous oil.The oil remaining on the Exxon Valdez, was completely offloaded by the end of the first week in April 1989. After offloading operations were completed, the tanker was towed to a location 25 miles from Naked Island in Prince William Sound for brief repairs. Later in the summer of 1989, the vessel was brought to California for further repairs. Shoreline treatment Shoreline assessment was a prerequisite for the implementation of any bea ch cleanup. Assessment provided geomorphological, biological, archaeological and oiling information that was used for the development of site particular treatment strategies.Cleanup operations were scheduled around specific activities such as seal haulout activity, seal pupping, double birdie nesting, fish spawning, fishing seasons, and other significant events as much as possible. pic pic Shoreline treatment from the Exxon Valdez spill. (Source Exxon Valdez Oil Spill Trustee Council) In 1989, hoses spraying seawater were used to flush oil from shorelines. The released oil was then detain with offshore boom, and removed using skimmers, vacuum trucks (useful for thick layers of oil) and boom (sorbent, snare, pompoms).For hard to reach areas, or locations with weathered oil, heated seawater was used to flush oil from the shoreline. Converted vessels and barges were used for beach washing operations. It would take some(prenominal) days to outfit a conventional barge with the equip ment needed to heat and pump the water. littler vessels that were used for beach washing early in the spill were re-outfitted for bioremediation subsequent in the response. Along with the large-scale beach washing, manual cleanup, raking and tilling the beaches, oily debris pickup, enhanced bioremediation and spot washing were used to cleanup the oil.In some locations, oil was thick enough to be picked up with shovels and buckets. In addition, mechanical methods were used on a few sites, including the use of bulldozers to relocate or remove the contaminated beach surfaces. Mechanical rock washing machines, which were manufactured for the spill, were not used to clean contaminated rocks and return them to the beach. Oiled storm articulatio humeri was mechanically relocated in some cases so that these areas, which normally would not receive much wave action, would be more exposed and cleaned by natural processes.If the oiling in the shoulder joint was significant or obdurate it wa s tilled to free the oil or washed to optimize the cleaning. Recommendations were made to restrict the movement of berm to the upper third of the beach to ensure its return to the original location. pic pic Beach washing. (Source Exxon Valdez Oil Spill Trustee Council) Beach applications of dispersants were tried in several locations. Corexit 7664 was applied on Ingot Island, followed by a loosen up water wash. No significant change in oil cover or the physical state of the oil was observed as a result of the treatment. Some ecological impacts were observed in the tempered areas.It appeared that the effects were largely due to the intensive washing more than to the use of Corexit 7664, and were evident in intertidal epibenthic macrobiota. In addition, the dispersant BP1100X was applied to a test area on Knight Island. Toxicology studies indicated that the upper and lower intertidal biota were different from pre-application communities the day after dispersant application, and retur ned to pre-treatment levels after seven days. In May of 1989, the U. S. Environmental vindication Agency (EPA) and Exxon conducted bioremediation trials at two test sites on Knight Island in Prince William Sound.On the basis of these tests and other trials later in the summer, Exxon recommended the use of the bioremediation enhancement agents, Inipol (Inipol EAP22manufactured by Elf Aquitaine of France) and Customblen (Customblen 28-8-0 manufactured by Sierra Chemicals of California), and after treated over 70 miles of shoreline in Prince William Sound with these agents. Winter monitoring of the effects of bioremediation consisted of surveys of more than 20 beaches in Prince William Sound and the Gulf of Alaska.These studies determined that oil degradation had been enhanced on the shorelines monitored, but some debate existed over whether bioremediation was solely, or even largely, responsible. Cleanup operations in 1989 ceased by the end of September. all told parties involved in the response agreed that continuation of cleanup into the Alaskan winter would jeopardize the safety of cleanup crews. In addition, it was speculated that the winter storms in Alaska could significantly remove oil from shorelines, including sub-surface oil.By the end of the 1989 cleanup, more than 25,000 gobs of oiled waste and several hundred thousand pose of oil/liquid waste were collected and disposed of in landfills. Cleanup in 1990 began in April and ended in September. Surveys in the spring of 1990 showed that oiling conditions had been reduced or changed over the winter. Surface oil in 1990 was significantly weathered but sub-surface oil was relatively fresh in some locations. Cleanup techniques in 1990 focused more on manual methods of treatment such as hand wiping and spot washing as well as bioremediation.Mechanical equipment was used on a few sites. Bioremediation was more extensive in 1990, with 378 of the 587 shoreline segments treated that year receiving bioremediat ion application. In general, Inipol was applied in cases where surface oiling existed and Customblen slow release pellets were preferred for treating beaches with sub-surface oiling. Generally, beaches were habituated one to three treatments over several months. hit over the possible ototoxicity of Inipol led to recommendations for application of only Customblen on some sites.By the spring of 1991, the cathode-ray oscilloscope of the cleanup effort was greatly reduced. Manual cleanup, bioremediation, and very limited use of mechanical equipment were employed. Cleanup took place from May of 1991 through July of 1991. An important observation that resulted from the Exxon Valdez oil spill was that natural cleaning processes, on both sheltered and exposed beaches, were in many cases very effective at degrading oil. It took longer for some sections of shoreline to recover from some of the invasive cleaning methods (hot water flushing in particular) than from the oiling itself.Economi c impacts The State of Alaska funded a several studies of the short term economic impact of the Exxon Valdez oil spill. pic pic Recreational fishing in Alaska. (Source Exxon Valdez Oil Spill Trustee Council) 1. Recreational Sport Fishing Losses. This loss was estimated based on the impacts of the spill on sport fishing activity. One must consider the impact on the number of anglers, the number of sport fishing trips, the areas fished, the species fished for, and the length of these trips.For 1989 the loss was estimated to be between $0 and $580 billion dollars for 1990 the range was $3. 6 one thousand trillion $50. 5 million dollars. 2. Tourism Losses. The spill caused both negative and positive effects. The major(ip) negative effects were 1. Decreased resident physician and non-resident vacation/pleasure visitor traffic in the spill-affected areas due to lack of available visitor services (accommodations, charter boats, air taxis). 2. Severe labor shortage in the visitor indust ry throughout the state due to traditional service industry workers seeking high-paying spill clean-up jobs. 3.Fifty-nine percent of businesses in the most affected areas reported spill-related cancellations and 16% reported business was less than expected due to the spill. The principle positive impact was strong spill-related business in some areas and in certain businesses such as hotels, taxis, car/RV rentals and boat charters. 1. Existence value. Economists tried to estimate the damage to so-called non-use or existence value of the Prince William Sound region in the wake of the spill. This is an attempt top measure what cannot be observed in the marketplace the value to the public of a pristine Prince William Sound.They estimated existence value using contingent valuation, a survey approach designed to create the missing market for public goods by determining what people would be willing to pay (WTP) for specified changes in the quantity or quality of such goods or, more rarel y, what they would be willing to accept (WTA) in compensation for well-specified degradations in the provision of these goods. The results suggest an aggrragete loss of $4. 9 to $7. 2 billion dollars. In effect, these amounts reflect the publics willingness to pay to prevent another Exxon Valdez type oil spill given the scenario posed. . Replacement costs of birds and mammalians. These costs include the relocation, replacement and rehabilitation for some of the shorebirds, seabirds and the marine and terrestrial mammals that may have suffered injury or were destroyed in the Exxon Valdez oil spill. The values range from $20,000 to $300,000 dollars per marine mammal (sea otters, whales, seal lions, seals), $125 to $500 dollars per terrestrial animal (bears, river otters, mink, deer), and $170 to $6,000 dollars for seabirds and eagles. How much oil remains? ground on the areas that were studied in the aftermath of the spill, scientists made estimates of the ultimate fate of the oil. A 2001 National Oceanic and Atmospheric Administration (NOAA) study surveyed 96 sites along 8,000 miles of coastline. pic pic A pit dug on a Prince William Sound beach in 2001 revealing oil in the sediments. (Source NOAA) The survey distinguished between surface and buried oil. Buried or subsurface oil is of greater concern than surface oil. Subsurface oil can remain dormant for many years before being dispersed and is more liquid, still toxic, and may become biologically available.A disturbance event such as burrowing animals or a severe storm reworks the beach and can reintroduce unweathered oil into the water. Results of the summer shoreline survey showed that the oil remaining on the surface of beaches in Prince William Sound is weathered and mostly hardened into an asphalt-like layer. The toxic components of this type of surface oil are not as readily available to biota, although some softer forms do cause sheens in tide pools. The survey indicates a total area of approximately 20 acres of shoreline in Prince William Sound are still contaminated with oil.Oil was rig at 58 percent of the 91 sites assessed and is estimated to have the elongate equivalent of 5. 8 km of contaminated shoreline. In addition to the estimated area of remaining oiled beach, several other important points were evident 1. Surface oil was determined to be not a good indicator of subsurface oil. 2. Twenty subsurface pits were classified as heavily oiled. Oil saturated all of the interstitial spaces and was extremely repugnant. These worst case pits exhibited an oil mixture that resembled oil encountered in 1989 a few weeks after the spillhighly odiferous, lightly weathered, and very fluid. 3.Subsurface oil was also found at a lower tide height than expected (between 0 and 6 feet), in contrast to the surface oil, which was found mostly at the highest levels of the beach. This is significant, because the pits with the most oil were found low in the intertidal zone, closest to the zone of biological production, and indicate that the survey estimates are conservative at best. Ecosystem response to the spill Recovery is a very difficult term to define and measure for a complex ecosystem such as Prince William Sound. If you ask a fisherman from Kodiak Island, a villager from the town of Valdez, an Exxon engineer, or a NOAA iologist, you are likely to receive such different answers that you may wonder if they heard the same question. In particular, disagreements exist between Exxon and government-funded scientists, and un cognises persist, especially in understanding how multiple processes combine to drive observed dynamics. Despite this, there are some things k outrightn with a high degree of certainty oil persisted beyond a decade in affect amounts and in toxic forms, was sufficiently bioavailable to induce chronic biological exposures, and had semipermanent impacts at the race level.Three major pathways of long impacts emerge (1) chronic persistence of oil, biol ogical exposures, and population impacts to species closely associated with shallow sediments (2) delayed population impacts of sublethal doses compromising health, growth, and reproduction and (3) confirmative effects of trophic and interaction cascades, all of which transmit impacts well beyond the acute-phase fatality rate. Acute Mortality pic pic Sea birds killed by the Exxon Valdez oil spill. (Source NOAA) Marine mammals and seabirds are at great insecurity from floating oil because they have routine contact with the sea surface.Oiling of fur or feathers causes loss of insulating capacity and can lead to death from hypothermia, smothering, drowning, and ingestion of toxic hydrocabons. Scientists estimate mass mortalities of 1000 to 2800 sea otters, 302 entertain seals, and unprecedented numbers of seabird deaths estimated at 250,000 in the days immediately after the oil spill. deal mortality also occurred among macroalgae and benthic inverteb evaluate on oiled shores from a combination of chemical toxicity, smothering, and physical geological fault from the habitat by pressurized wash-water applied after the spill.Long-term impacts The persistent nature of oil in sediments produce chronic, long-term exposure risks from some species. For example, chronic exposures for years after the spill to oil persisting in sedimentary refuges were evident from biomarkers in fish, sea otters, and seaducks intimately associated with sediments for egg laying or foraging. These chronic exposures enhanced mortality for years. Indirect effects can be as important as direct exposure.Cascading substantiative effects are delayed in operation because they are mediated through changes in an intermediary. Perhaps the two generally most influential types of indirect interactions are (1) trophic cascades in which predators reduce copiousness of their prey, which in turn releases the preys food species from control and (2) provision of biogenic habitat by organisms that serv e as or create important physical structure in the environment. pic pic A wholesome stand of rockweed (Fucus gardneri) growing on a boulder in Prince William Sound. Source NOAA) Scientists have found that indirect interactions lengthened the recovery process on rocky shorelines for a decade or more. Dramatic initial loss of cover by the most important biogenic habitat provider, the rockweed Fucus gardneri, triggered a cascade of indirect impacts. Freeing of space on the rocks and the losses of important grazing (limpets and periwinkles) and predatory (whelks) gastropods combined to promote initial blooms of ephemeral green algae in 1989 and 1990 and an opportunistic barnacle, Chthamalus dalli, in 1991.Absence of structural algal canopy led to counterbalances in associated invertebrates and inhibited recovery of Fucus itself, whose recruits avoid desiccation under the protective cover of the adult plants. Those Fucus plants that subsequently settled on tests of Chthamalus dalli be came dislodged during storms because of the structural instability of the attachment of this opportunistic barnacle. After apparent recovery of Fucus, previously oiled shores exhibited another mass rockweed mortality in 1994, a cyclic instability probably caused by simultaneous senility of a single-aged stand.The importance of indirect interactions in rocky shore communities is well established, and the general sequence of succession on rocky intertidal shores extending over a decade after the Exxon Valdez oil spill closely resembles the dynamics after the Torrey Canyon oil spill in the UK. State of recovery The Exxon Valdez Oil Spill Trustee Council published a study in 2004 to assess the state of the resources hurt by the spill. Fifteen years after the Exxon Valdez oil spill, it is clear that some fish and wildlife species injured by the spill have not full recovered.It is less clear, however, what role oil plays in the inability of some populations to bounce back. An ecosystem is dynamic ever changing and continues its natural cycles and fluctuations at the same time that it struggles with the impacts of spilled oil. As time passes, separating natural change from oil-spill impacts becomes more and more difficult. The Trustee Council recognizes 30 resources or species as injured by the spill. Depending on their status as of 2002, these have been placed in one of five categories Not RecoveringThese resources are showing little or no clear rectifyment since spill injuries occurred Common loon Cormorants (3 species), cheer seal, Harlequin duck, Pacific herring, Pigeon guillemot Recovery unknown Limited data on life history or extent of injury is available. Current research is either inconclusive or not complete tearing trout, Dolly Varden, Kittlitzs murrelet, Rockfish Subtidal communities pic pic Sockeye salmon (Oncorhynchus nerka). (Source NOAA) Recovered Recovery objectives have been met Archaeological resources, denudate eagle, Black oystercatcher, C ommon murre, Pink salmon, River otter, Sockeye salmon RecoveringClams, Wilderness Areas, Intertidal communities, Killer whale (AB pod), marble murrelet, Mussels, Sea otter, Sediments Human uses Human services that depend on natural resources were also injured by the spill. These services are each categorized as recovering until the resources they depend on are fully recovered Commercial fishing, Passive use, Recreation and tourism, Subsistence Prior to the Exxon Valdez oil spill, there was no baseline date available for the abundant number of species existing in Prince William Sound.Because of this lack of data, numbers of oil spill-related casualties and recovery rates have been difficult to determine. Legal responsibility of ExxonMobil The settlement among the State of Alaska, the U. S. government and Exxon was approved by the U. S. territorial dominion Court on Oct. 9, 1991. It resolved various criminal charges against Exxon as well as well-bred claims brought by the federal a nd state governments for recovery of natural resource damages resulting from the oil spill.The settlement was comprised of criminal and civil settlements with Exxon, as well as a civil settlement with Alyeska Pipeline Service Company. Criminal Settlement Plea Agreement Exxon was fined $150 million, the largest fine ever imposed for an environmental crime. The court forgave $125 million of that fine in recognition of Exxons cooperation in cleaning up the spill and paying certain private claims. Of the remaining $25 million, $12 million went to the North American Wetlands Conservation Fund and $13 million went to the national Victims of Crime Fund.Criminal Restitution As restitution for the injuries caused to the fish, wildlife, and lands of the spill region, Exxon agreed to pay $100 million. This money was divided evenly between the federal and state governments. Civil Settlement Exxon agreed to pay $900 million in ten annual installments. The final payment was received in Sept. 2001 . The settlement contains a reopener window between Sept. 1, 2002 and Sept. 1, 2006, during which the state and federal governments may make a claim for up to an additional $100 million.The funds must be used to restore resources that suffered a substantial loss or decline as a result of the oil spill, the injuries to which could not have been known or anticipated by the six trustees from any information in their possession or reasonably available to any of them at the time of the settlement (Sept. 25, 1991). The response of ExxonMobil pic pic Exxon logo. ExxonMobil acknowledged that the Exxon Valdez oil spill was a tragic accident that the bon ton deeply regrets. Exxon notes that company took immediate responsibility for the spill, cleaned it up, and voluntarily compensated those who claimed direct damages.ExxonMobil paid $300 million immediately and voluntarily to more than 11,000 Alaskans and businesses affected by the Valdez spill. In addition, the company paid $2. 2 billion o n the cleanup of Prince William Sound, staying with the cleanup from 1989 to 1992, when the State of Alaska and the U. S. Coast Guard declared the cleanup complete. And, as tell above, ExxonMobil also has paid $1 billion in settlements with the state and federal governments. That money is being used for environmental studies and conservation programs for Prince William Sound.ExxonMobil hired its own scientists to study the impacts of the spill, and they come to different conclusions than many of the results published by government agencies and peer-reviewed academic journals. Exxons scientists acknowledge the lingering pockets of oil in the sediments, but they argue that they do not pose a serious risk. It is their position that that there are now no species in Prince William Sound in trouble due to the impact of the 1989 oil spill, and that the data strongly support the position of a fully recovered Prince William Sound ecosystem.Lessons learned from the spill The scientists who m onitored the oiled parts of Prince William Sound wanted to study the shorelines ecological recovery after an environmental disaster like the Exxon Valdez spill, and then use those lessons to better respond to future oil spills. Right now, their task is still incomplete. However, some of their findings have changed the way they debate about cleaning up oil spills, and about how ecosystems respond to such disturbances. Following are some examples of what they have learned 1.Clean-up attempts can be more damaging than the oil itself, with impacts recurring as long as clean-up (including both chemical and physical methods) continues. Because of the pervasiveness of strong biological interactions in rocky intertidal and kelp timberland communities, cascades of delayed, indirect impacts (especially of trophic cascades and biogenic habitat loss) expand the scope of injury well beyond the initial direct losses and thereby also delay recoveries. 2.Oil that penetrates deeply into beaches ca n remain relatively fresh for years and can later come back to the surface and affect nigh animals. In addition, oil degrades at varying rates depending on environment, with subsurface sediments physically protected from disturbance, oxygenation, and photolysis retaining defilement by only partially weathered oil for years. 3. Rocky rubble shores should be of high priority for protection and cleanup because oil tends to penetrate deep and weather very slowly in these habitats, prolonging the calumnious effects of the oil when it leaches out. . Oil effects to sea birds and mammals also are substantial (independent of means of insulation) over the long-term through interactions between natural environmental stressors and compromised health of exposed animals, through chronic toxic exposure from ingesting contaminated prey or during foraging around persistent sedimentary pools of oil, and through faulting of vital social functions (caregiving or reproduction) in socially organized species. 5.Long-term exposure of fish embryos to weathered oil at parts per billion (ppb) concentrations has population consequences through indirect effects on growth, deformities, and behavior with long-term consequences on mortality and reproduction. The Exxon Valdez also triggered major improvements in oil spill prevention and response planning. 1. The U. S. Coast Guard now monitors fully-laden tankers via satellite as they pass through Valdez Narrows, cruise by Bligh Island, and exit Prince William Sound at Hinchinbrook Entrance. In 1989, the Coast Guard watched the tankers only through Valdez Narrows and Valdez Arm. . Two escort vessels accompany each tanker while passing through the entire Sound. They not only watch over the tankers, but are capable of assisting them in the event of an emergency, such as a loss of power or loss of rudder control. Fifteen years ago, there was only one escort vessel through Valdez Narrows. 3. curiously trained marine pilots, with considerable experience in Prince William Sound, board tankers from their new pilot station at Bligh Reef and are aboard the ship for 25 miles out of the 70-mile transit through the Sound.Weather criteria for safe navigation are firmly established. 4. Congress enacted legislation requiring that all tankers in Prince William Sound be double-hulled by the year 2015. It is estimated that if the Exxon Valdez had had a double-hull structure, the amount of the spill would have been reduced by more than half. There are soon three double-hulled and twelve double-bottomed tankers moving oil through Prince William Sound. Two more Endeavor class tankers are under construction by ConocoPhillips, their expected induction into service is 2004 and 2005. . Contingency planning for oil spills in Prince William Sound must now include a scenario for a spill of 12. 6 million gallons. Drills are held in the Sound each year. 6. The combined ability of skimming systems to remove oil from the water is now 10 times gre ater than it was in 1989, with equipment in place capable of recovering over 300,000 pose of oil in 72 hours. 7. Even if oil could have been skimmed up in 1989, there was no place to put the oil-water mix. Today, seven barges are available with a capacity to hold 818,000 barrels of recovered oil. . There are now 40 miles of containment boom in Prince William Sound, seven times the amount available at the time of the Exxon Valdez spill. 9. Dispersants are now stockpiled for use and systems are in place to apply them from helicopters, airplanes, and boats. Further Reading Alaska Fisheries Science Center, NOAA. The Exxon Valdez Oil Spill How Much Oil Remains? Alaska Oil Spill Commission. 1990. Spill, the wreck of the Exxon Valdez implications for safe transportation of oil (Final report). Juneau, AK. National Transportation Safety Board. 1990.Marine Accident Report initiation of the U. S. Tankship Exxon Valdez on Bligh Reef, Prince William Sound, near Valdez, Alaska, March 24, 198 9. Washington, D. C. NTSB. NTSB/MAR-90/04. 255 p. Peterson, Charles H. , Stanley D. Rice, Jeffrey W. Short, Daniel Esler, James L. Bodkin, Brenda E. Ballachey, David B. Irons. 2003. Long-Term Ecosystem Response to the Exxon Valdez Oil Spill. Science 302 2082-2086. Disclaimer This article is taken wholly from, or contains information that was originally published by, the National Oceanic and Atmospheric Administration.Topic editors and authors for the Encyclopedia of Earth may have edited its content or added new information. The use of information from the National Oceanic and Atmospheric Administration should not be construed as support for or endorsement by that organization for any new information added by EoE personnel, or for any editing of the original content. reference book Cleveland, Cutler (Contributing Author) National Oceanic and Atmospheric Administration (Content source) Peter Saundry (Topic Editor). 2008. Exxon Valdez oil spill. In Encyclopedia of Earth. Eds. Cutler J. Cleveland (Washington, D. C. Environmental nurture compact, National Council for Science and the Environment). First published in the Encyclopedia of Earth August 17, 2006 Last revised August 26, 2008 Retrieved March 28, 2010. Editing this Article We invite all scientists, environmental professionals and science attentive individuals to help improve this article and the EoE by clicking here EDIT CITE EMAIL PRINT NCSE Boston University M1 Digital UniverseUnless otherwise noted, all text is available under the terms of the Creative Commons Attribution-Share equal license. Privacy insurance Terms of Use Neutrality Policy Supported by the Environmental Information Coalition and the National Council for Science and the Environment. Unless otherwise noted, all text is available under the terms of the Creative Commons Attribution-Share Alike license. Please see the Encyclopedia of Earths website for Terms of Use information. Supported by the Environmental Information Coal ition and the National Council for Science and the Environment. picpic
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