ASSESSMENT OF VULNERABILITY TO OIL CONTAMINATION OF KOLA BAY COASTS| Assessment of vulnerability to oil contamination of Kola bay coasts |
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KALINKA O.P., SHAVYKIN A.A., VASCHENKO P.S. Nowadays Kola Bay attracts attention as a possible source of oil contamination of the Barents Sea and the Arctic Ocean.In Russian and foreign Arctic (Kola …, 1997) this coastal area of littoral doesn’t have equals in concentration and scales of industrial and transport activity and, therefore, in combination of man impacts on marine environment. At present numerous projects on production, delivery and processing of oil and gas are carried out in Kola Bay. Seven oil- transferring complexes are already officially registered. In Kola bay it is planned to start one more large oil-transferring complex which will include marine and coastal parts in area of Lavna River estuary. Thus, Kola bay, its waters and coasts are objects of intensive nature management and objects of potential contamination at accidental leakages and oil spills. According to literature that at a flood of petroleum coastal and shore zones are most subject to oil contamination. Maps of integral vulnerability to oil spills plotted for the Barents Sea water area where maximum sensitivity ranks relate in its course to coasts (Shavykin, Kalinka et al., 2008) demonstrate it. The coast type, its geomorphological characteristics are basic for assessment of coasts sensitivity to oil contamination. Thereupon creation of an integrated pattern of coasts ranking, Kola Bay in this case, on their sensitivity to oil impact degree is actual. Such coast classification will allow to determine both the most vulnerable and more contamination-resistant areas, determining priorities of clearing that is the key moment of process of planning of operations on liquidation of contaminations in LARN plans (Sensitivity..., 1996). Work objective is definition of Kola bay coast types, shore ranking and assessment on a degree of their vulnerability to oil impact, map of bay coasts sensitivity plotting.In August 2008 scientists of engineering ecology department of MMBI organized and carried out expedition to Kola bay on a motorboat “Neptune – 2”. In the course of it coasts and the coastal zone of Kola bay were investigated and photographed. Types of Kola bay coasts and hydrodynamic features of its coastal zone were described on the basis of obtained results and available literature and materials collection. Kola Bay of the Barents Sea is a typical fjord of ice tectonic-erosive origin. The bay constitutes three elbows with its bends: northern, middle and southern (fig.1). Many inlets cut into the bay, Tuloma and Kola rivers run into the bay top. Dynamics of bay waters formed of tidal currents and fluctuations of level where semidiurnal component of clearly seen in southern elbow current runoff prevails and in nonperiodic currents and level changes caused both by local wind and baric systems passage above the Barents Sea waters. Mostly strong tides are registered in top of the bay and Tuloma river mouth. In the middle and northern elbows speed of surface currents is insignificant as area of their sections enlarges and waters volume during flows varies insignificantly. Intensity of storm wave roughness naturally increases from a bay top to its northern part and depends on seasonal variability of wave conditions. In northern elbow probability of heavy roughness sharply decreases from winter to summer. In the middle and southern elbows northern gusts are limited, therefore in summer conditions close to calm (Kola …, 1997) prevail here. Coasts of southern elbow are hilly. Slopes of hills on western coast are more sloping than on eastern one. The western coast of southern elbow is all along bordered by drying shoal. Harbour installations of Murmansk port are situated on eastern coast of southern elbow of the bay. Its waters cover all southern elbow of the bay. Coasts of middle elbow of the bay are indented and deep. The southeast coast into which some inlets cut into is more indented. Some shallow inlets cut into a northwest coast of this elbow. Northwest and partially southeast coasts are bordered by drying shoal strewed with stones. An edge of drying shoal is deep. Littoral and coast ground consists of stone, sand in some places. The western coast of northern elbow is formed by gentle slopes of high mountains and is almost all moss covered. It is more indented than eastern one, many inlets cut into it. Eastern coast of northern bay elbow is higher than western one. It represents a continuous chain of uplands steeply descending to water, depth. Littoral and coast ground consists of stone, sand and small-sized stone in some places (Locies …, 1995). Indexing system ESI (Environmental Sensitivity Index) for the first time introduced by American specialists in 1976 year (Jacqueline, Halls and et al., 1995) was used for assessment of a degree of negative oil impact on coastal zone. Index ESI or index of ecological sensitivity is a basic integral criterion of shore sensitivity to oil contamination. Quality and quantity coast characteristics underlie ranking, i.e. connection between coast composition and structure, physical processes which take place when oil spills get to coast. It is necessary to note that in our work we have used simplified and adapted to local conditions indexing system ESI. Parameters which determine the range of sensitivity index are: 1) geomorphological coast characteristics; 2) wind-wave coast loading; 3) climatic indexes 4) conditions and duration of natural oil keeping; 5) degree of oil penetration in vertical direction; 6) capability of natural oil burying and earth moving; 7) conditions of natural oil biodegradation. Using combination of enumerated parameters each coast area was given basic ESI index to oil contamination sensitivity which varies from 1 up to 10, where 10 are the most vulnerable areas of coastal zone: Index 1: artificial constructions and harbour installations On the basis of international ESI classification zoning of Kola bay coastal zone was made and map of coasts vulnerability to oil impact was drawn. Referred to certain index coast sections are colour marked on a map that allows visually determine the most vulnerable and more resistant sections of coastal zone. Preliminary results obtained during work show that in southern elbow of Kola bay its eastern coast up to Pinagory cape relates to 1 vulnerability index on geomorphological characteristics. It is harborage and oil spill impact on coasts will be minimal. The western coast of southern elbow and further north-up to Pitkova inlet in the middle elbow is bordered by drying shoal relating to 7 vulnerability index. Eastern coast of middle elbow up to Mokhnatkin cape refers to 7 vulnerability index as well because of drying shoals which are met in coast cutting sections up to inlet of Skalny cape. In Severomorsk area there are harbour installations and coast here has an index 1. On open coasts from Mokhnatkin cape up to Chalmpushka cape rip-rap is spread (vulnerability index 6). Eastern bay coast north-up to Chirkovy cape on open areas has homotypic structure and allows us to refer it to vulnerability index 2 on ESI scale, only in some inlets rip-rap and slopes going down to water and coated by vegetation is met. The same is on both coasts of northern elbow, where fractured rock yield and rock-lumpy demolition on open areas prevail (an index 2), in sparse small inlets rip-rap is spread (an index 6), on western coast near Las cape and over Bolshoy Oleny island there are drying shoals (an index 7). Over Sedlovaty island on western coast there is fine-sand beach with corresponding vulnerability index 3. Unfortunately, numerous inlets of the northern and middle Kola bay elbows cutting far into coasts which can be natural oil traps at oil outflows were not studied. These objects are considered to be closed areas and permission to free access there was not been obtained at this stage. Carried out investigation allows us to draw a conclusion that Kola bay coasts all along up to 55-60 % of total area have high index of sensitivity = 7, according to international ESI scale. Indexes 1 and 2 in total constitute 40-45 %, the rest area has indexes 3 and 6. Hereinafter it is necessary to carry out series of marine and coastal expeditions for detailed investigation of Kola bay coasts and inlet types in order to complete work on drawing up of full vulnerability to oil spills map of its coasts and waters. Such work should be important for LARN plans. References OIL AND GAS OF ARCTIC SHELF 2008
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