Source: Government of Greenland
Cairn Energy’s contingency plan has been prepared with assistance from Oil Spill Response Limited (OSRL), which is one of the world's leading oil spill response companies and is Cairn’s sub-supplier of oil spill response equipment and services.
OSRL has units in Great Britain, Bahrain and Singapore and is present on a permanent basis in Africa and Indonesia and is the largest international organisation with regard to oil spill abatement.The company's global efforts are, for example, based on aircraft which have been dedicated and are placed strategically so that measures may be taken rapidly and efficiently when abatement equipment is to be delivered to accident areas and when monitoring tasks are to be performed.
OSRL has very considerable experience in oil spill abatement as the company has participated in the abatement of almost all major oil spills in the past 25 years, for instance also in the cleaning up after the Macondo accident in the Mexican Gulf in 2010. Therefore, OSRL is one of the world's absolutely leading companies in the field of oil spill preparedness planning and the abatement of oil pollution. The company also has previous experience of emergency preparedness projects from, for example, the sea around the Sakhalin Island and from the northern Caspian Sea. Furthermore, OSRL has gained experience in oil spill response in Arctic environments through their close cooperation with colleagues from other oil spill response companies such as Alaska Clean Seas in the Beaufort Sea, NOFO in Norway and ECRC in Canada. Furthermore, OSRL provides consultancy and training to the British Antarctic Survey which is one of the world's leading environmental impact assessment centres and responsible for Great Britain's scientific activities in the Antarctic.
Three-tier response services
Cairn's and OSRL's response services are based on the ability to handle very large oil spills.An oil contingency plan describes which resources Cairn and OSRL can deploy depending on the scope of an oil spill. The preparedness to handle oil spills is divided into three levels, Tiers 1, 2 and 3 and has, as already mentioned, been established by Oil Spill Response Limited (OSRL). The classification of a three-tier emergency preparedness and alarm system is internationally acknowledged and is also used by the Danish navy, including Island Command Greenland.
In the case of minor oil spills (Tier 1) OSRL has installed equipment on the drilling units or the vessels around them that can solve the task.
In the case of medium spills (Tier 2) OSRL has placed equipment in Aasiaat, Kangerlussuaq and Nuuk to solve such a task.
In the case of major spills (Tier 3) equipment from OSRL will be mobilised from the principal port in Southampton, Great Britain. Chemicals, equipment and staff from here will be transported to Greenland by means of air freighters. It has been documented that the worst possible response time for Tier 3 equipment to a drilling location is 52 hours.
Collaboration with other organisations
Should the very unlikely situation occur that there is an oil spill which requires even more abatement resources, allowance has been made for this situation via OSRL's collaboration with six large oil spill response organisations which together with OSRL are part of the so-called Global Response Network (GRN).
Cairn and OSRL’s strategy for a potential oil spill depends on many factors such as weather conditions and type of oil.The abatement strategies are as follows:
Mechanical recovery: consists in removing the oil from the surface of the sea mechanically. The oil is contained by means of floating booms and is then pumped into a tank on board a ship, after which the oil is sailed to a reception facility.
In-situ burning: consists in burning the oil at the surface of the sea. The oil must be contained in the same way as in the case of mechanical pick-up, but with the use of special floating booms that can stand the heat after which the oil is ignited.
Chemical dispersion: consists in spraying the oil with a chemical dispersant. Dispersants work by reducing the tension between the oil and the water surface. When correctly added, the dispersant can dissolve the oil into small drops that are subsequently dissolved in the water column. Dispersants may be sprayed onto the oil either from the sea or from the air.
Which solution is the best one depends, as already mentioned, on many circumstances and in case of an oil spill it is necessary for Cairn to make a so-called Net Environmental Benefit Analysis to assess which abatement method will be best in the given situation. This analysis as well as the abatement method must be assessed and approved by the Bureau of Minerals and Petroleum and the National Environmental Research Institute (NERI) jointly.
Oil spill versus sea ice
One of the aspects that has been questioned a lot is what to do if there is an oil spill in sea ice?
First and foremost it is important to establish that drilling is not permitted in the sea ice season in Greenland. The drilling of wells in Greenland must stop at least two months before the sea freezes up so that there is time, if necessary, to drill a relief well and to abate and clean up after a potential oil spill.
Should the very unlikely situation arise that there is an oil spill and should the situation be that oil is left in the sea when the sea ice starts forming in the northern areas the plan is as follows:
Continue the cleanup as long as possible, depending on the scope and type of sea ice.
Studies from the last few years show that in-situ burning is suitable for abating oil spills in broken sea ice because the ice keeps the oil together so that both ignition and burning are more efficient. The possibilities and efficiency of in-situ burning in sea ice depend in particular on the density of the ice. In-situ burning of oil is most efficient when the ice cover is less then 30 % or more than 70 %.
It is possible to continue with mechanical recovery of oil in sea ice until the ice cover is 30 %.
Studies show that it is possible to use chemical dispersion to abate oil spills in sea ice. It takes longer for the oil to disintegrate because it lies in a thicker layer (whereby the ice prevents spreading on the surface of the sea, the evaporation of the oil is reduced and thereby the composition of the oil is preserved for a longer time) and because the effect of the ice of subduing the waves reduces the emulgation rate of the oil.
If it is not possible to remove all the oil from the sea ice immediately it will be monitored via satellites, etc.In addition, detailed oil spill simulation models have been made which give a good picture of the drift patterns of the oil. This means that it will be possible to resume the cleanup as soon as the ice melts. At that time ships, aircraft and the equipment mentioned under the Tiers 1, 2 and 3 plan will be deployed.
It is important to emphasise that in the unlikely situation of an oil spill, the cleanup will be initiated as quickly and efficiently as possible and efforts will be made to clean up the oil as quickly as possible.It is also important to emphasise that if any oil should be left in the sea when the ice starts forming, such oil will be monitored and the cleanup will continue when the ice has melted. The cleanup activities will continue until the area has been restored to an acceptable state. In that respect an oil spill in Greenland does not differ from all other places in the world, including the production that takes place in the Arctic areas, for example north of Alaska and north of Russia and Norway.
Greenland government publishes Cairn's oil spill response plans in effort to calm fears
Source: Government of Greenland