Title: About the oil tanker “Prestige” Authors: Javier J. Díez and Pedro Fernández Affiliation: Universidad Politécnica de Madrid. Addresses: C/Profesor Aranguren s/n. Madrid 28040. Spain. Email: email@example.com; firstname.lastname@example.org; Keywords: Emergency safety protocols, potential polluted vessel solutions, crisis criteria. Organizative structure Main subject: Safety at sea Abstract On the second half of November, 2002, the oil tanker “Prestige” sank in front of the continental shelf of the Atlantic Galician coast of Spain, after several days of fighting against weather. A series of different oil spills provoked during this process and some time later a large differed black tide. A certain confusion and disorder generated early in the first days led to a major national political conflict. The problem is analyzed taking into account four main aspects: a) The damage in the vessel and the diagnostic about its evolution. b) The type of oil and the knowledge about its behaviour. c) The knowledge about the maritime weather and its changes during the operation. d) Natural and infrastructural harbour conditions availability. And with the idea of the necessity of a coordinator institution that can integrate all the aspects in a management efficiently way. Introduction On November 13th, 2002, the oil tanker “Prestige” broke down with 77,000 tons of fuel in its tanks. Six days afterwards, the vessel sank into the Atlantic waters at 120 miles from La Coruña´s coast, reaching 3500 meters depth. That wreck was the beginning of four main oil spills that reached Galicia´s coast until January and subsequently affecting Asturias, Cantabria, Basque Country and France. According with the data collected in the work “Impacto de la marea negra del Prestige sobre las aves marinas” (SEO/Birdlife, 2003), between November 16th 2002, when the first oil stained bird was recovered, up to August 31st 2003 , 23181 birds were collected belonging to more than 90 different species: 6,120 birds were alive and 17,061 dead. The most polluted affected region was Galicia, in the case of polluted birds the amount of cases affected was more than 50 % of the registered cases in Spain. With 11,802 collected birds, the Common Guillemot (Uria aalge) has been the most affected species, which means 51 % altogether. With the example of the polluted birds affected we can appreciate the complexity and the many aspects that can be affected in a disaster like the spill of an oil tank vessel and even at great distances from the place it sank into the water. Another important aspect is the necessity of a strategy ready in place for these kinds of events that would minimise the impact that will occur when the best action solution is assumed. The disaster and its consequences were instrumented, informatively and politically, as both a missile and a smog leading to an increasing confusion and delay in decisions. So, the social and economic measures were adopted with efficiency and on time, but the technical and organizational decisions on the proper disaster process were insufficient or suffered strong delays. And the immediately posterior research of the acts and event has not been scientific or technical but mainly political. The first scientific-technical Committee with these aims took a month to be created; just to decide what to do with the two halves of the broken sank vessel and the undetermined oil remaining trapped in them. Even under a distant perspective the catastrophe of the “Prestige” may be currently considered distressing, but it may also be considered as accidental respect to the Spanish authorities, and the lack of an adequate structure to board it could not be attributed to any particular authority but to all of them, so that the political answer should have been to join efforts. Instead, the atmosphere became angrier. The Accident On Wednesday November 13th 2002, the oil tanker “Prestige”, with Bahamas flag, sent a May Day close to Cabo Finisterre (Galicia, Spain). The vessel asked for help to evacuate the crew due to a high degree list. It transported 77,000 tons of fuel. At 17:00 hours (local time) air inspection from the Spanish authority showed presence of oil from the vessel in the ocean waters, estimated later in about 4,000 tons. On November 14th the vessel was towed away from the coast. From that moment, the vessel followed an erratic route. At first North-West days 14th and 15th, then South, days 15th and 16th, and finally South West days 17th to 19th. Till the moment the vessel sunk, it dropped about 16,884 tons, and on the moment it sunk and days after about 46,000 tons. Black tides The 16th of November the first fuel black tide arrived to the shore, coming from the first leaked out fuel from the “Prestige”, affecting a coast line of 150 km. in the La Coruña province, specially in the municipalities of Muxía, Camariñas, Corme, Laxe and Baldaio, with bad affects in Malpica, Roncudo y Touriñan. The fuel arrived days later to the Cantabric Coasts. The second big fuel stain arrival occurred on the 29th of November in Muxía, moving the next days to the south, affecting the Atlantic island National Park on the 4th of December and the province of Pontevedra on the 6th of December. The wind changed the track of the oil to the north, and a third arrival of fuel reached part of the Rias Bajas, Ribeira y La Costa de la Muerte on the 18th of December. Finally the big mass stain of fuel went to the Cantabric Sea on the 23rd of December, affecting the North of Spain Communities. A fourth mass of fuel arrived to the La Costa de La Muerte on January 4th 2003. At that time, less quantity had arrived to the French coast. Till summer 2003 some small oil episodes were registered in some places in the coast; and during the whole summer a continuous episode of spots was registered all along the Galician and Cantabrian coasts. It happened as if a great reservoir of buoyantly dispersed oil was remaining in the middle of Bizcay Gulf submitted to successive cyclonic NW to NE summer winds. 743 sandy areas of a total of 1,064 were affected by the fuel according to the Spanish authority in the International Oil Pollution Compensation Funds (Comité Científico Asesor. 2003). Figure 1. Volunteer students from ETSI Caminos, Canales y Puertos of Madrid. During several months the black tides affected exclusively Galician Atlantic coasts. Initially all proceeded from the first great spill in front of the coast and, though it took a time to cross the few miles because of the veering round winds, Western dominance ended moving the oils, first to the east and northeast and later to southeast. Fortunately for Portugal, this spill was so close to shore that the presence of the Galician Atlantic Islands and the delay of the North component saved its coasts of the oil. Later on, dragged by SW wind currents, this first spill over passed the north headlands of Ortegal and Estaca de Bares and progressed, then dragged by more winter wind currents from W and NW until it reached the more oriental Cantabrian shores. This, supposing that the black tides which reached French coasts in The Landes could proceed from that first spill. The second great spill, poured out when the vessel broke in two halves and sank, delayed more in reaching the coast and most of it had to be mainly moved for a long time by the Gulf stream; a small part of it, still produced relatively near the surface, could reach and spread over the Galician shelf being dragged by wind currents towards Atlantic, and later Cantabrian, coasts; but it had to be scarce enough to not be able to affect to Portuguese coasts either. The apparently great new affection of the Atlantic Galician shores had to be mainly due, therefore, to the removal of the oil deposited on the rocks and cliffs during the first tide. Figure 2. Oil route. Map developed by SASEMAR. The General Frame of the Sea Disaster Circumstances One of the principia that the past management of the disaster brought was the lack and necessity of an organization structure to resolve these crisis situations in an effectible manner, to put to work all the resources available in time. To the role of the three Spanish administrations: Local, Autonomic and National, we must add the inconvenience of a rather deficient international maritime law and organization structure. Back to the present disaster it can easily lead to confusion with the complexity and quantity of different technical questions that define the problem: vessel, polluted load, climate, oceanic circulation, coast morphology, available infrastructures, and logistic aspects in the saving operations. But it was clear that a general plan coordinating al least many of the principal aspects never existed and that at least general and clear conceptual ideas were not taking in account certain elements like the following: A damaged vessel will probably break with longer wave length which occurs far from the coast. Not all the fuels are the same and their characteristics have to be known immediately, which, for example, can oblige that the vessel never reach an inhabited area. Also important are the winds and their role in the superficial currents, their relative importance compared with other currents, the Galicia coast morphology, that offers many “rías” where a vessel could hypothetically get safer conditions in an emergency event. The harbour infrastructure prepared or adapted for these events with the appropriated recovering planning cost would be the beginning of a new discipline relative to the study of this success, which time to time comes back to the same area with worse consequences. That the vessel was not in very good conditions to this kind of traffic along such a conflictive route was generally supposed from the beginning, and very soon generally assumed too, and that, as a consequence, the sea rules are clearly insufficient to avoid or control these accidents. And this question pertains to international politics in such a way that exceeds any possible scientific or technical discussion; so it is only possible here to call the attention about it. But any country can adopt immediate measures in the case of a such disaster when it happens in its territorial waters and the damages are going to affect mainly, if not exclusively, to its littoral and coastal areas. And they must obey to decisions taken with the best criteria. To conform these criteria an adequate management structure must previously exist permitting fast and efficient communication within the scientific community and between this and the organism of decision. The Damage of the Vessel and the Diagnostic about its diviner. The damage was produced in the starboard side of the middle of the vessel hull causing the immediate pouring of the oil from a couple of its tanks there, though the spilling was not perceptible on real time because of the atmospheric and oceanic weather conditions. It happened close to the coast, a few miles from it, under a fine storm from SW veering round to W and to NW, and for a couple of days the nearly uncontrolled vessel awaited the decision about its course and, very soon, the arrival of tugs. The decision was finally imposed by the Spanish Minister who opted for ordering to remove it far away from the shore taking advantage from a new southern stormy condition. This decision was surprisingly taken after being consulted several high ministerial officials, all of them with nautical or naval architecture formation. Therefore all of them must know that moving the vessel away increased the risk of breaking it because of the increasing wave length; a wounded vessel in the middle of its length increases its risk of breaking going out off the continental shelf, and this is fine narrow in Galician and Portuguese littoral; a previous similar case in the southeaster Mediterranean Spanish coast close to Almería had been successfully solved in this way, but in the Mediterranean successive storms are not so frequent, wind wave lengths are rather shorter and swells are rather less developed, all of those circumstances, among others, which make less probable to reach the wave conditions for breaking the vessel; besides other morphological differences in the coastal morphology that we shall consider later. From this point of view, therefore, it would have seemed more advisable to lead the vessel to some harboured place on the coast; there are several rías close, though their availability could be, and it was later, rejected due to both, the necessity of effective shelter due to the wind wave directions and the necessary depth. Two rías that met both were La Coruña and Ferrol, with their respective harbour and port facilities; nevertheless local authorities early and angrily rejected such options, politically making it nearly unfeasible. Undoubtedly the decision was adopted in a very passionate atmosphere, but nothing was done on time to try to acquire knowledge of the vessel characteristics and conditions to accurately evaluate its behaviour and risks before taking the decision. The information was looked later to assign liabilities. Figure 3. North Iberian Peninsula continental platform. Oil type and the knowledge about its behaviour. Not all of oils are the same and, in spite of the opacity of the oil business, the accurate knowledge of one of them is always possible before taking irreversible decisions in a case of accident like the Prestige’s. In this case, however, the information about the oil has been deficient a long time, having had many successive data which have been shown wrong some time later, in such a way that any decision could be easily mistaken. At the beginning, for instance, it was informed that the proportion of the volatile fraction was high, what supported the rejection to the entrance of the vessel into the ría and port of La Coruña, while finally was it was known that the volatility was low, in agreement with the high density, very similar to the sea water’s. This high density was the cause of the very low buoyancy shown by the oil of the second spill. Volatility can be linked to human toxicity, although higher density and viscosity can slow the reversibility of the destruction of the ecosystem of a ría. Spreading, miscibility, emulsification, combinability, are proprieties depending of the composition and nature of the oil and affecting the disturbing behaviour of it, and must be taken into acoount for any decission about what to do with any accidentedly broken vessel as the Prestige. And, like in the case of the vessel and the nature of its damage, the knowledge of the nature and characteristics of the oil was wrong and insufficient, when it is sure that many scientists could have obtained on time enough good information to take an appropriate decision. However no adequate informative network could be used for it. Knowledge about the sea climate and the sea weather forecasting. Current winds constitute a major factor in the spreading and breaking up of the oil spill and in the dragging of both the oil spill and its spots; dispersion is mainly induced through the turbulence generated by wind waves, while surface and subsurface dragging is mainly due to the wind currents; and, obviously, current transferences from the wind are more inertial than wave’s. When the oil spill is still remaining under subsurface, dragging is due (under a certain depth) to general ocean currents (as Gulf stream) or, upon a certain height under the sea level, to drift (Coriolis) currents, both much more inertial. Decisions in a disaster like Prestige’s must therefore count on the knowledge of the current environmental conditions and, particularly the sea climate and weather. As the main environmental factors in this case, for the maintenance or movements of the vessel as for the prevision and control of the oil spill dragging and dispersion, depend on the winds and wind waves, an accurate wind and wind wave forecasting must have been available from the beginning, immediately after the accident and before taking any decision about the vessel. Nevertheless news or knowledge about it were missed at all times, what must be understood as a proof that they were not used in the decision; if they had been used or even known, they would have been obviously widely divulged. And it has been evident that the right knowledge of that forecasting throughout the episode was necessary, and it could have led to different decisions, particularly in relation with the destination of the vessel, but also for the black tide foresight. We are afraid too that the behaviour of the different kind of currents in the different zones of the affected area was also forgotten or, at least, not wholly taken into account. The Gulf Stream was ignored for a very long time and, if that could be acceptable in relation with the first oil spill, even in relation with the last one if its oil had been highly volatile, it could lead to gross mistakes for the foresight and prevention of the black tides. In fact, the spots of the second great oil spill reached first the shores of the French peninsula of Brittany, and even the Channel waters, before the shores of the Landes. Figure 4. Main currents in winter (left) and in summer (right). Natural and infrastructural harbour conditions availability. This is also a main question for the management of all the events of the disaster. It has been mentioned before the case of a previous event in front of the southeaster Spanish peninsular coast, when another oil tanker was not allowed to enter for shelter in the Almería harbour and which was likely considered a precedent; in that case, the vessel received shelter in Malta harbour, a little farther than Almería. The main reason of the Spanish authorities then could have been to safeguard the tourist overcrowded beaches and the Natural Park of Gata Cape; and although Galicia is not so much demanded in its shoreline, especially as late in the year as in November, its coasts are especially fishery productive and it has a lot of protected natural estuarine and island coastal areas. Nevertheless, besides other several important differences between both cases (much less storm frequency and smaller wind wavelengths in the Mediterranean, more distance to the coast when accident happened and significant differences in the respective vessel characteristics and conditions) the different morphology of the coasts is very notorious; as a matter of fact, Galician are the only irregular coasts in the Iberian Peninsula, with abundant sheltered areas, though not all of them sufficiently deep for any requirement. In fact, the accident happened in the surroundings of the ría of Camariñas, where possibilities of searching one could be tried or studied. Of course artificially harboured areas in this ría, as in most of Galician, except perhaps that of Vigo, La Coruña and Ferrol, lack the depth and perhaps the surface extension enough to permit the receiving a vessel like the Prestige. Figure 5. Ría of Camariñas. As a matter of fact, actually Camariñas ría is open to the west, the direction of main and more frequent winds and waves, to which all south winds evolve before to veer round the north. To reach another greater ría, is necessary to pass in front of one of the two major capes of the Coast of the Dead, Finisterre to the south or Villano to the north, wich practically frame that ría and the place where the vessel broke. But finally, near of both capes, several major and probably suitable rías were available. Southward, nearly any of the Rías Bajas permit to search sheltered conditions under any weather conditions, because of their morphology and orientation or the presence of the Atlantic Islands. Figure 6. Galicia. In fact however most of Rias Bajas open their mouths to SW or W and only the Muros’ open to W-NW, so that a better chance could be offered by the northern Artabrian Rías Altas. In the Artabrian gulf there are three rías together, La Coruña is open to NW-N and has a good harbour artificially sheltered versus the NW-N wind waves. Ares is wider but open also to the SW, and Ferrol is open to the W-SW but it is the widest totally sheltered natural harbour with complete facilities for vessels. Of course, the draught of the load and scored vessel did not permit to warrant the success of the entrance and searching or mooring in any of them, but none objective and dispassionate analysis seems to have been done, and the decision was rounded of a very passionate atmosphere. Figure 7. Rías of Arosa, Pontevedra and Vigo. Conclusions It is very noticeable the complexity and multiplicity of the aspects that were affected in the disaster of the Prestige, in which the breaking, firstly partially and near to the shore, and the sinking, when finally the breaking was total in two halves, of the oil tank vessel; with the consequence of the successive spills; all of which, and even at great distance from the coast the last, occasioned a tremendous back tide on a extremely long coastline. That a damaged vessel will probably break with more long wave length which occur far from the coast, and that not all the fuels behave in the same way and suppose the same type of threat; that the winds, waves and their role in the superficial currents, their relative importance compared with other currents, and the coast morphology, offer in Galicia, with so many “rias”, a notorious singularity; that the necessity of some harbour infrastructure prepared or adapted for these events with the appropriated recovering planning cost, and of a new discipline relative to the study of these successes, that time to time comes back to the same area with worse consequences; all of them have become issues in scientific and even political discussions. But the lack and necessity of an organization structure to resolve these crisis situations in an effectible manner, to take advantage on time of all the available resources, appears in our opinion as the main factor in the problem, and we must trust that the Office created by the Spanish government can be sufficiently successful. We must add the necessity of radically improving the international maritime rules. Acknowledgments To the former Commissioned’ Office and current Office for Sea Contamination for their information and data. References Alvarez Fanjul, E. Establecimiento de un sistema español de Oceanografía operacional. Puertos. N. 118. pp. 57-64. Madrid. 2004 Comité Científico Asesor, Comisionado para el Prestige. Resumen del informe sobre la neutralización del pecio. Vicepresidencia del Gobierno de España. www.ccaprestige.es. Madrid 2003. Diez, J. J. Sobre la modernidad y el des”prestigio”. Diario de León, 30.12.02. p.4. 2002. Caminos, informative bouletin. N. 107. pp. 106-107. UPM. Madrid. 2003. Laura García, Carlota Viada, Rubén Moreno-Opo, Carles Carboneras, Agustín Alcalde y Felipe González. Impacto de la marea negra del Prestige sobre las aves marinas. SEO/Birdlife ISBN: 84-931722-6-X. 2003.
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