Expansion of oil and gas operations raises environmental concerns

These occurrences are rare, and the industry takes considerable measures to avoid spills. While many though massive oil spills were a thing of the past, events in the Gulf of Mexico in 2010 proved different. So, there is a lot of trepidation from environmental groups around taking operations further north and in to the Arctic. Yet, with global demand making the price of fossil fuels ever greater, progress is almost certainly going to continue. It is a black and white issue for many that polarises those that argue for or against. The oil and gas industry is taking steps to deal with the eventuality of an oil spill and wants to find out how the unique conditions of the Arctic will affect any response. To help understand the challenges, members of the International Petroleum Industry Environmental Conservation Association (IPIECA), Oil Spill Working Group (OSWG), Industry Technical Advisory Committee (ITAC) and the American Petroleum Institute (API) Emergency Preparedness and Response Program Group (EP&RPG) set-up the Arctic Oil Spill Response Technology Joint Industry Programme (JIP) in January. The consortium is supported by nine international oil and gas companies including BP, Shell, Statoil, and Total. It is to build on existing research and improve the technologies, and methodologies, for dealing with a potential oil spill in the Arctic. It will carry out 10 in-depth research projects around six key areas including computer modelling of oil behaviour in Arctic conditions to help map and predict the trajectory of spills, the effectiveness of chemical dispersants in Arctic waters, mechanical recovery, detection, the actual environmental impact and in-situ burning. The Arctic also offers some particular operating challenges such as prolonged periods of darkness, extreme cold, distant infrastructure and sea ice. At present, oil spills are generally dealt with in three main ways. The first is mechanical recovery, second is using chemical dispersants and third is in-situ burning. However, before dealing with any oil, it must first be located. "In the Arctic we are looking to develop tools that can locate oil that is underneath ice or that has been encapsulated in the ice," say Joseph Mullin, programme manager of the Arctic Oil Spill Response Technology JIP. "Advanced remote sensing, not only from the surface but possibly from the sub surface by the use of autonomous underwater vehicles, are areas we are looking at." The Arctic is almost continually dark during winter months where vast ice sheets can spread quickly. Conversely during summer month's ice can rapidly break up in to sizeable chunks and recede. One of the projects aims to expand remote sensing and monitoring capabilities, especially in darkness and low visibility. The project will test the effectiveness between surface remote sensing that utilises satellites, aircraft and ships to subsea sensing that will use remotely operated vehicles (ROV). "We have to be able to send a response to where there is a 'meaningful' amount of oil," says Mullin. "We need the right equipment dealing with the 'right kind' of oil. Some equipment works very well on light oil on the surface, but once it gets heavy and emulsified that equipment might not work as well." Perhaps the most interesting aspect of the project is mechanical recovery. Ultimately this is what all parties would like to see. The oil companies would be able to recover potential revenue, while potentially damaging oil slicks would be removed from the environment. The use of mechanical recovery is normally always favourable and usually a primary response option. Containment booms are normally used in combination with a skimmer to remove oil from the surface of the seawater. It can then be stored before further treatment. However, Arctic waters offer both some advantages and disadvantages. Booms and skimmers deployed from ships collect large chunks of ice floating in the water. This quickly causes blockages and makes this approach almost completely ineffective. "The more ice you have, the harder it is to use mechanical recovery," says Mullin. "If you have a spill and the water is more than 50% frozen you can't use a boom anymore. "We currently have four sub-projects looking at better ways to separate oil, water and ice. These are looking at new ideas and seeing how effective and feasible they will be." There are, however, some conditions in the Arctic that could actually be beneficial to any response. Waves in the Arctic do not generally reach the ferocity frequently witnessed in the North Sea, meaning spilt oil does not spread so rapidly from the source. Additionally, the temperature of the water keeps oil more viscous. "That, too, will actually slow down the spreading of the oil," says Mullin. "If you spill oil in water that is 30°C then it will spread out quite quickly. Colder temperatures aid the responder as the oil doesn't spread as fast, and also it doesn't 'weather' as quickly. The result is that the window of opportunity to effectively respond to an oil spill is a bit longer." Several types of skimmers and vessels have been developed specifically for recovering oil in ice-covered regions. The skimmers are often brush belts, drums or ropes rotating through the slick and capable of recovering oil while processing small ice pieces. Some skimming units are even equipped with heating systems, ice deflection frames, and advanced pumps able to handle viscous oil, water and ice mixtures. One of the deliverables of this JIP is to access the possibility of onboard oil/water/ice separation systems. The study will evaluate the feasibility of putting theses on board vessels, and new recovery vessel design concepts. Shell has suggested that an empty oil tanker or similar could be deployed in conjunction with a vessel that would pump an oil, ice and water mixture in to it. The modified tanker would then be able to process the mixture and separate out the oil while at sea. However, as well as the more high-tech options, there are more common and (at the risk of punning) crude ways of dealing with oil spills. Indeed, a significant part of the JIP is to establish the use of dispersants and in-situ burning in Arctic conditions. Dispersants are either a chemical or mineral added to water to enhance the natural biodegradation process of oil in the marine environment. "As with washing dishes, you need to agitate the water to remove the grease," says Mullin. "Dispersants break the oil down into very minor particles that you suspend in the water column and these are then available for bacteria to further breakdown and use as a food source." The use of in-situ burning is also relatively common. The oil slick on top of the water must be about 3mm and must not be emulsified (i.e. the oil must not have taken on too much water content). While both these methods are effective in taking oil out of sight, they do not remove it from the environment. Chemical dispersants have been shown in some studies to do more harm than good, and in-situ burning creates plumes of black, particulate-rich smoke into the air. Responders face difficult decisions and are cleaning up oil that we all are guilty of demanding. It is a case of minimising damage as much as possible. This JIP wants to ask difficult questions so that something like the Gulf oil spill never happens in Arctic waters. Such scenes, if repeated in the white serenity of the Arctic, could potentially spell the end of operations there permanently. And that really is something the oil and gas industry is desperate to avoid. "I don't know of any responder who wants to go out there and hurt the environment," says Mullin. "What we want to find out is the best ways of using different technologies in the Arctic, and which are most effective in a given situation."