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North Sea Oil & Gas – A Scientific overview, the Elgin incident and the Environment. Martin Preston Honorary Research Fellow University of Liverpool. The Environmental Law Enforcement Conference, EDINBURGH 2013. Overview. History of oil and gas spills The tensions in spill management
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North Sea Oil & Gas – A Scientific overview, the Elgin incident and the Environment Martin Preston Honorary Research Fellow University of Liverpool The Environmental Law Enforcement Conference, EDINBURGH 2013
Overview • History of oil and gas spills • The tensions in spill management • Why the Gulf of Mexico spill and Elgin gas leak were different • Decommissioning in the North Sea • The international future – the push to high latitudes and deep waters
What are ‘oil’ and ‘gas’? • Oil is formed by the heating of reservoirs of plant material over geological times • Natural gas – chemically simpler - formation is much the same but involves heating of the material at higher temperatures • Crude oil is a very complex mixture of thousands of individual chemicals ranging from gases to tars. No two are identical - fingerprints • The `recipe` of crude oils depends on region, oil field specific well and time
History • Oil seeps known for several thousand years – bitumen used to seal boats and containers, fix weapons to shafts, treat skin ailments and wounds and even in the preparation of Egyptian mummies • One of the earliest shipments in 1539 when a barrel of crude was shipped from Venezuela to Spain to alleviate the gout of Emperor Charles V* • Gas seeps used in Zoroastrian temples • First refining by Gessner in 1846 in Nova Scotia produced kerosene. First refinery in Romania in 1856 Anibal Martinez (1969). Chronology of Venezuelan Oil. Purnell and Sons Ltd
History • With the advent of the internal combustion engine demand soared 1 barrel = 160 litres
History – European oil traffic North Sea production supply>demand
Largest tankers • 1928 16346 GRT and this size maintained until after WW2 • 1956 Suez crisis meant ships needed to traverse Cape of Good Hope so much larger tankers were built • 1967 Torrey Canyon 120000 DWT • 1979 Largest tanker >500000DWT could not transit English Channel since scrapped • Today Largest working tankers 441,500 DWT
Largest tanker spills ITOPF 2013
All marine spills Exxon Valdez Ixtoc 1
Ixtoc 1 1979 Gulf of Mexico Ixtoc 1 1979 480 000t
Piper Alpha 1988 North Sea 167 personnel killedwith only 61 survivors
Piper Alpha 1988 North Sea A complex accident which led to a gas explosion Oil to gas rig conversion Pressure safety valve A removed for maintenance Key paperwork missing Failure in B system led to switch back to A which was not gas-tight Gas exploded Worst accident to date Memorial to Piper Alpha victims in Aberdeen
Elgin 2012 North Sea You are here http://bcove.me/0ejf9rwz
The 4 damage factors • What is it? • Where is it? • How much of it is there? • What time of year/weather is it/
Recovery factors • Temperature • Flushing characteristics • Uniqueness of damage site • Reproductive strategy of endemic organisms • Marginality of key species
Exxon Valdez • Not in top 20 of big spills • But probably the most damaging spill of all time • Avoidable accident • Pristine, high latitude environment • Bad weather at key moments • Badly handled response – poor planning and implementation
Tensions in Accident Management • Industrial/corporate • Social/economic – perceived risk vs actual risk • Political – the need to be seen to be doing something • Legal • Environmental • Media • Scientific
Obama needed to show that he was the man in charge but in reality there was nothing much he could do. In this region there is also the memory of Hurricane Katrina and the poor initial response of the Bush administration. He was also, even at this stage, concerned about the mid-term elections. Use of British Petroleum rather than BP stoked tensions between US and UK The irony is that if this had happened to a US drilling company he would almost certainly needed to call BP in as consultants to fix the problem Conflict President Obama – a man with authority but no power in this instance faced with mid-term elections The US legal system seems to encourage compensation claims so there is an incentive for lawyers need to maximise the worst case and ‘scare’ people into signing up with them. Local politicians have to reflect the concerns of their electorates (and many of them in this area are also republicans so no inclination to support Obama) Scientists are scampering around the edges of all this trying to get ship time and equipment but caught in the bind of not knowing whether to accept research money from BP. I did a lot of media work over this period and I was always asked whether I had taken oil company money (or belonged to an NGO) before they would go ahead. And through it all the media are frantically trying to find a new story to keep the cameras rolling. A long incident is quite difficult for news media because they can end up running out of new things to say. The tendency can be to ramp up the hype to try and keep people’s attention. For an objective scientist asked to comment this can be a particular problem. Local concerns about fishing and tourism i.e. economy The fishing and tourism industries had different imperatives. Fisheries were closed so they needed compensation and had some interests in maximising the problem. The tourist industry was desperate to minimise the problem so as to get people visiting again BP trying to stop spill under oversight of official US administration and manage PR with real time video coverage Scientists trying to get reliable field data Lawyers keen to develop compensation claims. Local politicians having their say Media desperate for new stories
Elgin - minimal conflict • Elgin accident was well managed – rapid evacuation of personnel effective therefore no Piper Alpha • Information flow was slow and press conferences given in French • Site was inaccessible and cloud covered so no pictures • All appropriate actions taken with minimum fuss and maximum effectiveness • Whether accident could have been completely avoided is unclear
OSPAR Rules Offshore Installations • 1998 OSPAR Ministerial Meeting, • the dumping, and leaving wholly or partly in place, of disused offshore installations is prohibited within the maritime area • Some exceptions (e.g. for steel installations weighing more than ten thousand tonnes in air or gravity based concrete) http://www.ospar.org/
Offshore structures in OSPARCOM area Pipelines? According to the latest update of the inventory, 145 installations have been decommissioned.
Brent Spar – Shell 1995+ NGO intervention led to cancellation of dumping plans and subsequent recycling in Norway However Greenpeace did not come out unscathed when their data was faulty
Benefits through presence alone • 500m exclusion zone • 1284 still in commission • Equivalent to ~1000km2 • Area of North Sea 750000km2 • So ~.13% in exclusion zones
Possible benefits of non-removal • Exclusion zones maintained • Drill cuttings undisturbed • Alternative uses • Centres for offshore energy generation wind/wave? • Desalination using solar power • Fish farms • Seal observation platform (German) See Royal Academy of Engineering Report http://www.raeng.org.uk/news/publications/list/reports/RAEng_Offshore%20_Decommissioning_Report.PDF
Carbon capture and storage CCS • Currently most interesting option • CO2 from industrial processes/power generation captured and injected into aquifers/spent gas reservoirs • This reduces CO2 emissions to atmosphere and influences global warming • Norwegians/Statoil already using Sleipner field has reduced emissions by 106 tonnes over 10 years • Around 6 UK projects in progress. First online ~2015/16?
The Future • Shale gas versus offshore gas? • Oil/gas price versus recovery costs? • CCS as a tool in managing climate change • Deeper – colder – more remote • International versus national waters • Territorial disputes e.g. Arctic
Conclusions • Accidents have become less frequent • Both real and perceived damage can be minimised by proper planning, preparation and execution • The future of North Sea activities will be determined by • Price of hydrocarbon extration • Obsolescence and decommissioning • Alternative activities including energy generation and CCS • The threat of accidents is moving to high latitudes, deep waters and (potentially) the far East.
