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No. 719: The western Greenland Sea. A preliminary strategic environmental impact assessment of hydrocarbon activities in the KANUMAS East area

Boertmann, D., Mosbech, A., Schiedek, D. & Johansen, K. (eds) 2009.

Summary and conclusions

This document is a preliminary Strategic Environmental Impact Assessment (SEIA) of activities related to exploration, development and exploitation of hydrocarbons in the sea off Northeast Greenland between 68° and 81° N. The KANUMAS East area (Figure 1).

The KANUMAS project was a regional seismic exploration programme that was initiated at the end of 1989. A group of companies, the KANUMAS group, was then granted a prospecting licence to the KANUMAS areas. The Kanumas areas also encompass the Greenland part of the Baffin Bay – the KANUMAS West area.

The prospecting licence did not include any exclusive rights to the licensee, and the licence implied a considerable obligation of exploration. This was balanced by granting the KANUMAS_companies a special preferential position. This preferential position will be activated if the right to petroleum exploration in Northeast and Northwest Greenland is put up for licensing.

The SEIA was prepared by the National Environmental Research Institute, Denmark and the Greenland Institute of Natural Resources in cooperation with the Greenland Bureau of Minerals and Petroleum.

The assessment area is shown in Figure 1. This is the region which potentially could be impacted by oil exploration and exploitation activities within the expected licence areas, although drift modelling indicates that an oil spill may drift further than the extent of this area.

The expected activities in the ‘full life cycle’ of a petroleum field are briefly described. Exploration activities are likely to take place during summer and autumn, because harsh weather and particularly sea ice hamper activities in winter and spring. However, if oil production is initiated activities will take place throughout the year.

The environment

The physical environment of the study area is briefly described with focus on oceanography and ice conditions. Sea ice and icebergs are present throughout the year, with the lowest concentrations in August and September. One of the most important physical features of the biological environment is the polynyas (ice-free or almost ice-free areas surrounded by sea ice). The most important polynyas are found at the entrance to Scoresby Sund, at Wollaston Forland and at the northeast corner of Greenland (the Northeast Water), see Figure 5. These polynyas become free of ice very early in spring (April) and also have ice-free parts throughout the winter.

An updated account of some of the physical conditions was issued in late 2008 by the Danish Meteorological Institute (DMI) (Hvidegaardet al. 2008).

The study area is situated within the Arctic region, with all the typical biological properties of this climatic region: low biodiversity, but often numerous and dense animal populations; a relatively simple food web, from primary producers to top predators, with a few species playing a key role in the ecology of the region (Figure 6). In the marine environment the most significant event is the spring bloom of planktonic algae, the primary producers in the food web (Figure 6). These are grazed upon by zooplankton, including the important copepods of the genus Calanus, which is one of the key species groups in the ecosystem. Copepods again form the most important prey for small fish, large crustaceans as well as some seabirds and marine mammals.

Benthos is the fauna living on and in the seabed. Benthic macrofauna species are an important component of coastal ecosystems. They consume a significant fraction of the available production and are in turn an important food source for fish, seabirds and mammals. Very little is known on the benthos communities in the assessment area.

In and on the underside of the sea ice a specialised community exists: the sympagic flora and fauna. Algae live in and on the ice and are grazed upon by crustaceans, which in turn sustain populations of polar cod and Arctic cod.

Fish, seabirds and marine mammals represent some of the higher trophic levels in the marine environment, where polar bear and man are the top predators.

Fish fauna is low in diversity, but some species are important: the polar cod is very numerous, both pelagic and associated with the ice, and constitutes a major food resource for seals, whales and seabirds. It is one of the key species. Other important species are Greenland halibut and Arctic char. Capelin occurs in the southeastern offshore waters.

Seabirds are locally abundant with several species present in the study area in summer and spring. Many species breed in colonies mainly close to the polynyas, where dense aggregations of birds can be found as early as May. In spring and autumn millions of seabirds migrate through the area on their passage between Svalbard and Russian breeding sites and Canadian wintering sites. The most important species are common eider, thick-billed murre, little auk and ivory gull (Table 1). Almost all the seabirds leave the area for the winter to return in May and June. Thick-billed murre, common eider and black-legged kittiwake are all red-listed in Greenland due to declining populations, although mainly in West Greenland . Other red-listed bird species which occur in the marine part of the assessment area include Sabines gull, Arctic tern and light-bellied brent goose. Also ivory gull is red-listed, mainly because of the expected reductions in its primary habitat, sea ice. The coasts of the Northeast Water are a stronghold for this species.

Furthermore, some species are designated as species of national responsibility, which means that the population in Greenland is so large that the local management of the species is vital to the entire population. The most important of these species is the little auk. Other national responsibility species occurring in the marine part of the assessment area are black guillemot and light-bellied brent goose.

Marine mammals are significant components of the ecosystem. Four species of seals as well as walrus, many species of whales and polar bear occur in the assessment area. The most important species are narwhal, bowhead whale, walrus, harp seal, hooded seal and polar bear (Table 2). They are often associated with ice edges, polynyas or shear zones, where open water is present, and harp and hooded seals assemble in large numbers on the drift ice in March to whelp and later to moult.

Polar bear, walrus and bowhead whale are red-listed because their populations are small, declining or expected to decline because of climate change (polar bear).

The open waters to the east of the drift ice are very little known with respect to marine mammals. But whales occurring frequently in Icelandic waters (blue, fin, sei, humpback, sperm whale etc) may be similarly frequent in eastern parts of the assessment area.

Human use of natural resources only occurs in the southern part of the assessment area. Subsistence hunting (marine mammals and seabirds) and a little fishing is carried out near the town of Scoresbysund and hunters from Tasiilaq occasionally venture as far north as the southernmost part of the assessment area.

Commercial fishery is limited to Greenland halibut and this takes place in offshore areas in the southern part of the assessment area. The catches are small compared to other parts of Greenland .

Tourism is a growing industry in Greenland , and this is also the case in Scoresbysund, where activities take place from early spring (April) and throughout the summer. There is a local operator and also a few Icelandic operators which have activities in the Scoresbysund area.

Knowledge on background levels of contaminants such as hydrocarbons and heavy metals is important in assessing environmental impacts from petroleum activities. The available knowledge on background levels of hydrocarbons in the assessment area is limited, but the general picture is that levels are low.

Assessment

Exploration

The environmental impacts of exploration activities will mainly be disturbance from activities creating noise such as seismic surveys and drilling. The impacts are expected to be relatively small, local and temporary, because of the intermittent nature of the exploration activities. Furthermore, the season for exploration activities is very short and limited to the few months with light ice conditions (July–September). No severe impacts are expected if adequate mitigative measures are applied, activities in sensitive areas are avoided in the most sensitive periods and no accidents such as oil spills occur.

Temporary impacts of intensive seismic activity could be displacement of Greenland halibut, which again could cause reduced catches in fisheries near affected areas.

Marine mammals, particularly whales, may also be displaced from critical areas as feeding grounds. However, as seismic surveys are temporary such effects are expected to be of short duration (e.g. weeks or a maximum of a few months). In case of displacement, availability to hunters may also change.

Unless a zero-discharge policy is applied, drilling mud and cuttings will be released on the seabed, with local impacts on the benthos as a consequence. During exploration, when it is expected that wells are few and dispersed, this impact can be minimal and local with proper mitigation, but impacts may be more severe if development and production is initiated (see below).

There is always a risk of oil spills from blowouts during exploration drilling (see below).

Development and production

The activities during development, production and transport are on the other hand long-lasting and there are several activities which have the potential to cause severe environmental impacts. Careful Health, Safety and Environment (HSE) procedures, application of Best Available Technique (BAT) and Best Environmental Practice (BEP), zero-discharge policy and planning in combination with thorough background studies and application of the Precautionary Principle can mitigate most of these. Even though discharges and emissions can be limited, there will be a risk of cumulative and long-term impacts from many of the released substances, but knowledge is generally limited in this field.

The largest contribution to the pollution from an oil field is the discharge of produced water (if not re-injected). This contains, besides oil residues, small amounts of substances which are acutely toxic or radioactive, contain heavy metals, have hormone-disruptive effects or a nutrient effect. Some of the substances may bio-accumulate, although long-term effects of release of produced water are unknown. There is, however, an increasing concern about the environmental impacts of this activity. Particularly if produced water is released under ice, where there is reduced turbulence in the surface layer, increased impacts could occur. The most obvious way to mitigate effects of produced water is to re-inject it into the wells.

Discharge of ballast water is of concern, as there is a risk for introducing non-native and invasive species. This is currently not a severe problem in the Arctic , but the risk will increase with climate change and the intensive tanker traffic related to a producing oil field.

Development and production are energy-consuming activities which will contribute significantly to the Greenland emission of greenhouse gases. A single large Norwegian production field emits more than twice the total Greenland emission of today.

Commercial fishery will be affected by development and production if installations are placed in the fishing grounds. A safety zone (of typically 500 m) will be applied around the offshore facilities. Commercial fishery is currently limited and takes place only in the southern part of the assessment area.

Placement of structures and the disturbance related to these have the potential to displace in particular marine mammals. Noise from drilling platforms has displaced migration routes of bowhead whales in Alaska . Depending on the location of installations, displacement of migrating and staging whales (mainly narwhal and bowhead whale) and walrus must be expected. This can in certain areas limit their access to critical habitats which could be important for survival, and walrus is the most sensitive species in this respect, because the population is dependent on relatively few and localised benthic feeding areas. Furthermore, displacement can result in reduced availability of quarry species for local hunters.

Placement of offshore structures and infrastructure may locally impact seabed communities and there is a risk, in some shallow areas, of spoiling important feeding grounds, particularly for walrus. If onshore structures are established there will be a risk of river obstruction impacting anadromous Arctic char and damage to unique coastal flora and fauna.

Intensive helicopter activity also has the potential to displace seabirds and marine mammals from critical habitats (e.g. feeding grounds important for winter survival) and from traditional hunting grounds used by local people.

Finally, placement of structures and installation onshore will also have an aesthetic impact on the landscapes, an issue especially important to consider when evaluating impacts on tourism.

Development and production activities are difficult to evaluate when their location and the level of activity are unknown. Overall, impacts will depend on the number of activities, how far they are scattered in the areas in question, and also on their durability. In this context cumulative impacts will be important to consider.

Careful planning in combination with thorough environmental background studies, BEP, BAT and application of the Precautionary Principle can do much to limit and mitigate impacts from development and production, e.g. by avoiding the most sensitive areas and avoiding activities in the most sensitive periods.

Oil spills

The environmentally most severe accident would be a large oil spill. This has the potential to impact the marine ecosystem on all levels from primary production to the top predators. The recent oil and gas assessment by the Arctic Council working groups (AMAP 2007) concluded that the main issue of environmental concern for the marine Arctic environment is a large oil spill, which particularly in ice-covered waters represents a threat at the population and even species level. Furthermore, will the lack of adequate response methods in ice-covered waters and the remoteness and lack of infrastructure in most of the assessment area add to the severity of an oil spill.

Accidental oil spills may occur either during drilling (blowouts) or from accidents when storing or transporting oil. Large oil spills are rare events today due to ever-improving technical solutions and HSE policies. However, the risk cannot be eliminated and in a frontier area like the KANUMAS East with the presence of sea ice and icebergs, the possibility of an accident will be elevated.

Oil spill trajectory modelling was carried out by DMI as a part of this SEIA. In most of the modelled oil spill drift scenarios oil does not reach the coasts, but stays offshore. However, two of the 18 scenarios indicate that under certain conditions, oil may reach shores up to several hundred kilometres from the spill site.

In general, oil spills occurring in the coastal zone are regarded as much more deleterious than oils spills in the open sea. This may, however, not apply in an area such as KANUMAS East, which is dominated by sea ice for the major part of the year. Ice may trap and transport oil over long distances, but may also limit the spread of oil slicks compared with the situation in ice-free waters and even protect shores from being polluted. Furthermore, the ice edges, leads and polynyas are very important in a biological sense and therefore potentially very sensitive to oil spills. Knowledge on the behaviour of oil spill in ice-covered waters is however limited.

The coastal zone is sensitive because of the high biodiversity present, including concentrations of breeding and moulting seabirds and Arctic char. The high sensitivity is also related to the fact that oil may be trapped in bays and fjords where high and toxic concentrations can build up in the water. Furthermore, local fishermen and hunters use the coastal zone in the southern part of the assessment area intensively.

Long-term impacts may occur if oil is buried in sediments, among boulders, in mussel beds or is embedded in crevices in rocks. From such sites oil may seep and cause chronic pollution which may persist for decades. In Prince William Sound in Alaska such preserved oil has caused long-term effects on birds utilising the polluted coasts.

Effects of an oil spill in the open sea (without ice) are expected to be less severe than in coastal areas. Attention should be given to potential oil spills in areas with hydrodynamic discontinuities, such as hydrographic fronts or upwelling zones, particularly during the spring bloom. However, knowledge on these events in the KANUMAS East assessment area is very limited.

Bird populations particularly at risk of being impacted by an oil spill in the KANUMAS East area include the large breeding colonies of little auk and the two thick-billed murre colonies, all at the coasts of the Scoresby Sund polynya. Furthermore, the large assemblages of pre-breeding eiders in the polynyas will be very exposed. Some red-listed seabird species (e.g. thick-billed murre, ivory gull) occur in the assessment area and the populations of these will be exposed to increased mortality in case of a large oil spill.

Marine mammals can also be impacted by oil spills, although individuals (except polar bears) are not dependent on an intact fur layer for insulation. Polar bears are an exception to this, because they are very sensitive to oiling of their fur. Walrus and bearded seal feeding on benthos may also be exposed to oil through their food if oil sinks and accumulates on the seafloor. Bowhead whales, which occur in low numbers (and are red-listed), belong to a stock which was almost exterminated by heavy exploitation. The recovery of this population may be halted by even a slight increase in mortality.

There are special problems related to oil spills in ice. Oil will, at least in the beginning, tend to be contained and the spread limited, unlike the situation in ice free waters. Oil will be contained between the ice floes and on the rough underside of the ice. However, oil caught in or under the ice may be transported in an almost un-weathered state over long ranges and may impact the environment, e.g. seabirds and marine mammals, far from the spill site when the ice melts. Oil may also be caught along ice edges, where primary production is high. Particular concerns have been expressed about polar cod stocks, because this fish spawns in late winter, and the eggs accumulate just below the ice where spilled oil will also accumulate. This could also be the case if produced water (with dispersed oil) is released from a platform in ice-covered waters.

In this context it is worth noticing that recent studies indicate that at least killer whales are very sensitive to inhaling oil vapours. This could apply to narwhals and bowhead whales, which often occur in densely ice-covered waters. During a large oil spill such areas with limited open water will be covered by oil and whales will be forced to surface here. Walruses and other seals living in the ice may also be vulnerable to this scenario.

The seals whelping on the drift ice will be very exposed to an oil spill in the area and many adults and pups may be fouled. Adult seals are rather robust to oiling, but pups are more likely to succumb. Walruses are also sensitive because the population is concentrated at relatively few sites and also because they are gregarious.

Even though seals may tolerate some oil on their fur, such oiling may impact local hunters, as fouled skins are of no use and are impossible to sell.

Oil spill effects on commercial fisheries are mainly linked to the closure of fishing grounds (Greenland halibut) for longer periods (weeks to months) due to the risks associated with marketing polluted or tainted fish. Effects on subsistence hunting and fishing will include closure of polluted coasts and probably also temporary changes in the distribution and habits of quarry species.

The tourist industry in the assessment area is also expected to be negatively impacted by a large oil spill.

This assessment is based on current conditions. However, climate change may alter these conditions considerably and the present assumptions may not apply to the future. Therefore reservations should be attached to some of the conclusions when looking a number of decades ahead.

Further studies

There is a general lack of knowledge on many of the ecological components and processes in the KANUMAS East area. To fill some of these data gaps, BMP, GINR and NERI have initiated a number of studies which will proceed in 2009 and 2010. The results from these studies will be incorporated in the revised and updated SEIA, planned to be issued in 2010. See section 13 for a review of the projects.

Many more knowledge gaps remain to be filled and there will be a need for further regional strategic studies as well as project-specific studies in order to have adequate data to perform site-specific EIAs. A full analysis of data gaps will be included in the 2010 SEIA. A preliminary list of the most important studies identified so far is given in section 14. Some of these knowledge gaps are generic to the Arctic and have also been identified in the Arctic Council Oil and Gas Assessment (AMAP 2007, Skjoldal et al. 2007), and relevant studies will hopefully be initiated by cooperative international research. But there are also knowledge gaps specific to the assessment area.

Full report in pdf  (20.7 MB)

 

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Revideret 12.04.2012

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