Rarely discussed at street level, ‘Carbon Sequestration’ is at the forefront of discussion at the highest levels of government and business, particularly those in the power and energy areas. Australia is considered to be a market leader in this area, a situation that throws up some interesting anomalies.

You hear plenty in the media about global warming, unfortunately with very little accompanying background facts or relevant information. You know the sort of reporting – Scientists say polar icecap melting faster than at first thought etc. You then get some blithe gibberish about some study or other, a few meaningless quotes, some pretty visuals of ice walls crashing into the sea and to finish the segment a projection of polar bear survival rates going off into the future. Then it cuts to the next segment, perhaps about Nicole Kidman’s new dress or the new man in her life and that’s the news.

To give it some perspective, outside of the economy and events in the Middle East, global warming or more importantly, prospective action to inhibit its progress is just about the hottest inter-governmental topic on the planet. At the top of the list of mitigation strategies is carbon sequestration which means – for the uninformed – pumping large volumes of Carbon Dioxide (CO2) into underground hidey holes and hoping it stays there for a very long time.

In Australia, the discussion regarding geologic storage of waste materials has been visited before – many times. The latest was 4 –5 years ago with the nuclear waste dump proposal from Pangea Resources who were majority owned by British Nuclear Fuels Limited. The plan was firmly rejected once the public found out what the proposal entailed but not before many senior public figures warmed to the proposal and the revenue it might create.

CO2 sequestration or geologic storage raises many issues and it is important these issues are openly discussed. There are multiple sites around the country that have been identified and/or lined up as suitable depositories and figures of over 100 million tonnes of CO2 a year are being quoted as a realistic potential storage target. It must be in the public interest to know the integrity and background of the proposed storage sites, what exactly is being stored and the level of monitoring that will be utilised once the process has been implemented. It is particularly important where proposed storage sites are close to or beneath any areas of high population density even if the majority of the sites are remote from population centres

Why is Australia regarded as a ‘leading nation’ in the area of Carbon Sequestration?

Given Australia’s decision not to ratify the Kyoto Protocol on the basic principle of ratification being detrimental to its commercial interests, it may come as a surprise to many that Australia is currently regarded as the world’s leading nation in development of the commercialisation of subterranean CO2 sequestration. The reasoning behind this situation is a long drawn out affair and requires taking the reader through the process of how the carbon sequestration concept came about.

The background to global warming

The build up of greenhouse gases in the atmosphere, primarily from the use of fossil fuels as the main global energy source has led to a situation of rising temperatures on a worldwide scale. From the ‘hole’ over the Antarctic to the melting of the polar icecap in the Arctic, scientists overwhelmingly agree that the rise in temperatures is causing climate change, a situation most people are familiar with. The latest study on the Arctic situation released recently, describes an alarming increase in the pace of localised effects from rising temperatures. The forward projections even with remedial actions being put in place makes disconcerting reading. Concern at the international level has been around a long time and was such that the Kyoto Protocol was instigated in Rio in 1992 as a means of facilitating and implementing multilateral action to arrest the situation.

Kyoto Protocol

The essence of Kyoto was to apply a multilateral response mechanism to a global problem over an extended timeframe, thereby transcending the normal short-term political inertia that tends to dominate most sitting governments around the world. As is often the case in world politics, governments tend to disagree with one another, usually along economic lines and Kyoto has proven to be no different in that respect. There was significant doubt as to whether the Kyoto Treaty would be ratified at all because the US, Russia and Australia had backed away from ratification. However, Russia recently agreed to ratify the agreement which meant a threshold had been reached for full implementation of the principles of the protocol, beginning this year.

Although well intentioned, the Kyoto Protocol is divisive in its implementation. Australia, the world’s heaviest polluter per capita and the US, the world’s heaviest polluter by volume have refused to ratify the agreement on economic grounds. It is felt the imposition of greenhouse costs on industry will impair competitiveness and drive domestic electricity prices much higher. Besides, emerging nations such as China were not included in the original emissions targets set for each country. Of course the emerging nations’ viewpoint is that they didn’t cause the problem in the first place so they shouldn’t be penalised with emissions targets in the first instance. These general disagreements and a few others apart, all countries have recognised that global warming is a problem for everyone and each has subsequently initiated various strategies for tackling the problem at various levels, including alternative energy strategies.

Subterranean disposal, sequestration, call it what you like

Whilst consideration of the move to cleaner burning fuels and alternative energy sources has been a positive outcome in the bid to halt global warming, the process of actual implementation is a slow one because of economic and political considerations. The world is still heavily dependent on oil for transportation systems and predominantly coal for power generation. On the issue of coal for power, it was recently reported in the Christian Science Monitor that, between them, the US, China and India have over 800 new, coal-fired power plants on the drawing boards! How many does Australia have?

There has been some positive progress in the development of alternative energy sources and the hydrogen economy is being touted and funded but realistically, is 25 years away at best. Should the peak oil scenario be anywhere near true then going nuclear may be the only short term power generation option for many countries. So you have global warming requiring a solution and a potential situation where the world’s ever increasing supply of nuclear waste will likely be considerably added to – enter the idea of subterranean geologic, CO2, hazardous waste disposal, sequestration, call it what you like.


In 1991, Norway introduced a US$55 a tonne carbon tax on CO2 emissions into the atmosphere from fossil fuel combustion sources such as coal-fired power plants which was extended a short time later to include oil and gas development activities. At the time the Sleipner West gas field in the Norwegian sector of the North Sea was under development, a gasfield with high concentrations of CO2 (9%) in the produced product. Normally the excess CO2 of around a million tonnes a year would have been vented into the atmosphere but the new tax obviously imposed an approximate US$55 million a year cost burden on the project. Statoil, Norway’s state oil company and operator of the project looked at ways of reducing the cost burden applied by the tax, eventually coming up with the idea of pumping the excess CO2 into a subterranean saline aquifer approximately 1000 metres below the seabed and 2500 metres above the reservoir they were developing. A novel response.

It was never in the repertoire of costs to run an extensive monitoring program at Sleipner because if the CO2 seeped out, it would seep out into the ocean. The oceans already hold billions of tonnes of CO2 and have themselves been considered as a potential disposal location for atmospheric CO2 by many agencies. Production of gas from the field and injection of excess CO2 into the subterranean aquifer began in 1996. To date this is the only place in the world, and a direct result of where CO2 is geologically disposed of, as a strategy to mitigate for cost impositions created by GHG (GreenHouse Gas) emissions policy.

In mid 1998, the IEA (International Energy Agency) put together a consortium to fund geologic and monitoring tests at Sleipner The project was called SACS (Saline Aquifer CO2 Storage). This was a full 2 years after CO2 injection had commenced and an afterthought. The geological testing was difficult because early seismic, drill sections, and various other mandatory source materials from the Sleipner sequestration site were either of poor quality or just not available. Consequently, a good deal of the significant scientific testing was deferred from the original SACS manifesto to the SACS 2 project which was to follow on behind the original program. So far there has been little information made available about SACS 2. As of October 2004, available data is written in a way that suggests the project is still ongoing although the same IEA document states the program is completed.

Of more interest is the consortium brought together by the IEA to underwrite all this research. It consisted of the following organisations:

BGS – British Geological Survey

Statoil – Norwegian Oil Company

BP – Oil major

ExxonMobil – Oil major

Vattenfall – Power company – nuclear

NorskHydro – Diversified Industrial

TotalFinaElf – Oil major

BRGM – French Geological Survey

Geus – Geological Survey of Denmark & Greenland

IFP – French Petroleum Institute

SINTEF – Scandinavia’s largest independent research organisation

NITG-TNO – Netherlands Institute for applied geoscience

The mix in this grouping shows that the issue of subterranean geologic storage is of immense interest to government and all areas of the energy business, including those with other waste materials from the production of energy.

By all accounts the Sleipner experiment has been successful in terms of proving up the basic physical concept of being able to reinject CO2 into a subterranean aquifer and being able to ‘see’ the injected CO2 utilising modern seismic techniques. However, what is less clear with carbon sequestration are the costs associated with the geotechnical and ongoing monitoring requirements. That is, sufficient to enable a credible economic model to be produced for incorporation into future demonstration or commercial applications – of which to date there have been none, which probably speaks for itself.

Finding published data on costs in this area is extremely difficult but it is not difficult to map out a reasonable bare minimum of requirements. Regular time lapse seismic over the area, interpretation, modelling and quality control and that’s just the bare minimum. Inspectors, geologists, scientists, environmental experts and that’s before the requisitions start coming in for the equipment needed to adequately complete the ongoing monitoring process. I think you get the picture.

More independent research

A short while after the SACS initiative from the IEA, other organisations with an interest in the concept decided to get their own independent evaluation of the carbon sequestration potential. The project, which is ongoing, is called the “CO2 capture project “and is funded by the following organisations:


Chevron Texaco



Norsk Hydro



Suncor Energy

US Dept of Energy

European Union

The institution chosen by the partners to complete the original work was the Earth Sciences Division of the prestigious E.O. Lawrence Berkeley National Laboratory of Berkeley, California. This institution has produced 8 Nobel Prize winners in various scientific fields, so one would expect its research to be rigorous and indeed it was. However, the type of language and concerns expressed in their reports was not what was wanted to be heard and a short while after receiving a ‘yellow card’ via a US$50,000 funding cut, reporting by the original team of geoscientists at LBNL was disposed of – so to speak. The solid technical reporting was replaced with reports filled with typical corporate babble which were extremely light on any meaningful technical detail. The final report by LBNL is a very large public document which is required reading in this whole area. It points out in fairly graphic terms what is involved in the area of carbon sequestration and why it is extremely important to employ a ‘steady as she goes’ doctrine to the process. The location of the document for retrieval purposes is noted at the end of this article.

Where does Australia fit into all of this?

It can be clearly seen that many western governments and large multi-national corporations have pounced on the potential of carbon sequestration. It must appear like a simple panacea to an awful lot of vexing problems. The trouble is, unless the geologic and monitoring ‘spade work’ has been delineated and completed on an individual case by case basis, and framed in a legal process then it is hard to see any system working. This is the particular case with the Gorgon gas development in Western Australia. The development is being driven by the politics and economics of geologic waste disposal and not by the economics of a straightforward LNG development. The Gorgon project is the next big test for the geologic disposal of hazardous materials, including CO2. It is being driven by an international agenda and has tacit Australian Federal Government approval. How so?

Australian government involvement in geologic waste disposal

Dr Peter Cook is a senior Canberra mandarin – he implements policy, otherwise he wouldn’t hold the positions he does.

Dr Cook is the Chief Executive of CO2CRC, the part government funded organisation that is leading the charge in the full scale commercialisation of geologic storage in Australia. CO2CRC hold the ‘GEODISC’ database, a previous government initiative out of the APCRC (Australian Petroleum Cooperative Research Centre) that identified prospective geologic ‘storage’ sites all around the country. The GEODISC program also investigated risk assessment as one of its key challenges. GEODISC was to develop and trial an appropriate quantitative risk assessment methodology, the aims of which were to compare alternative CO2 storage sites on the basis of the risk of leakage, the effectiveness of the storage reservoir for injection and storage, and any adverse consequences arising from CO2 storage on any site.

Peter Cook was previously Chief-Associate Director of the BMR (Bureau of Mineral Resources) from 1982-1990 and a Director of the British Geological Survey from 1990 to 1998. Prior to his current position at CO2CRC he was Executive Director of APCRC who manaed the GEODISC project. He also had his own consulting company, PJC International P/L.

Peter Cook is unreservedly in favour of the geologic disposal of nuclear waste in Australia and has debated the issue on a number of occasions in public forums. He was also a consultant to Pangea Resources during their bid to get an international nuclear waste dump up and running in Australia.

It would be inconceivable to separate the issues of nuclear waste disposal and CO2 sequestration because in effect they both add up to the same thing, regardless of any individual project emphasis.

Linkage back to industry and international agenda

The CO2CRC is part funded by industry, including many of the same companies mentioned beforehand. However, one of the more interesting sponsors of CO2RC is the giant US conglomerate URS Corp. URS Corp. is a well established cog of the not to be mentioned US military/industrial complex and makes a significant proportion of its annual turnover (of approx US$3.5 billion) from logistical and hazardous waste operations for all branches of the US military. A URS subsidiary, Business Risk Strategies and their risk assessment product ‘RISQUE methodology‘ has been incorporated into GEODISC to front the various issues that may crop up in the ‘sensitive’ area of geologic disposal of hazardous materials. An interesting aspect of some CO2CRC literature is that of ocean tankers pulling up and emptying their cargo into storage sites deep beneath the seabed.

URS Corp and the Gorgon project operator, Chevron Texaco are from the same neck of the woods in California and work closely with each other in the area of hazardous waste, site remediation and GHG emissions. This brings us to why industry and governments around the world are waiting for Australia to ride in at the head of the cavalry and make things somewhat easier for the process of subterranean geologic storage/disposal to commence on a significantly wider scale.

The proposed Gorgon LNG project in Western Australia is the template for proving up a regulatory framework for geologic sequestration. As well as project operator Chevron Texaco, both Shell and Exxon/Mobil also have an interest in the project and will be footing a substantial part of the capital and operating expenditure to make the project run. Just about everybody wants this project to proceed because effectively it has a bearing on the wider development of approximately 25% of Australia’s known gas reserves which means big dollars. However, the planned site for the development, Barrow Island off the West Australian coast is designated as an ‘A’ class nature reserve and is home to various fauna and flora found nowhere else on the planet. The Gorgon project is discussed in a separate article in this document and should be read in conjunction with this article to get the complete picture on what is involved from a fuller perspective.

A published overview of how the International Energy Agency categorises the Gorgon project is shown at the end of this article. The language used to describe certain aspects of the project is interesting bearing in mind it will be a world first, is taking place in an extremely environmentally sensitive area and considering the massive volumes of CO2 involved. A proposed figure of 5 million tonnes a year of CO2 being sequestered underground at this project has been widely reported although not in the data below. One would have thought a more suitable project and location could have been found as the main template for such an important process. Monitoring requires time lapse seismic which can be very damaging to the local environment depending on which process is used. It is also extremely expensive. However, when one understands the position in regard to public access to Barrow Island then it becomes somewhat clearer to see why this location has been chosen. In short, should you just rock up to Barrow Island whilst out boating for the day you will be rounded up by a goon squad and asked to leave immediately, in the nicest possible way of course. Access to the island is strictly controlled through the operating oil company and is fully backed up by legal statute that leaves no room for argument.

Monitoring sequestered CO2

Part of the contentiousness with geologic sequestration is the regulatory framework, status and legal requirements for ongoing monitoring of the sequestered product going forward. In short there isn’t anything in place. This obviously poses many questions about who is going to set the rules, will it be government or will it be the private sector? This issue alongside other legal considerations as well as that of providing financial indemnity should there be any unforseen calamity with the sequestered product are under discussion at international levels but as yet nothing has been finalised or written into international law. The Gorgon project is time sensitive from a commercial perspective because large LNG projects need certain supply commitments in place to justify the large capital expenditures involved in projects of this nature. It will be interesting to see if the final go ahead is forthcoming from government in light of the issues still to be discussed or resolved satisfactorily at the international level.

Emissions trading and Carbon credits

The picture on straightforward CO2 sequestration is not complete without a brief discussion on the issue of emissions trading and carbon credits. This is another sensitive and contentious area because it effectively involves the monetisation of, or giving a monetary value to pollutants in the atmosphere or a reduction thereof. Essentially, carbon credits and the emissions trading market were formed to assist governments and/or the private sector to gain flexibility and financially from pursuing environmentally friendly policies or commercial operations. The Kyoto Protocol sets emissions targets relative to 1990 levels which for many governments might mean introducing new, more restrictive mandatory emissions regulations and for private companies introducing new pollution control technology or reducing GHG emissions from their facilities thereby incurring a potentially large cost imposition.

The carbon credits system has wide ramifications for carbon sequestration in Australia and raises a whole series of questions about who gains what and how any ‘credits’ will be confirmed, distributed and accounted for. The system is a logistical and legal minefield but there are already companies and countries out in the marketplace seeking to pay money to buy someone else’s environmentally friendly GHG reduction credits. I foresee many articles clarifying this process further going forward. In the meantime, keep a lookout in the media for material related to the area of carbon sequestration as it is going to be an extremely important topic as we move through the current decade.


Dear Australia,

Your country has been chosen by the international community as the destination of choice for some of our most noxious substances. You will be well rewarded financially for being friendly and cooperative world citizens. Just ensure the next stage in the process is put in place with the current opportunity before you.

This article is just a brief overview of a highly contentious global issue and how it is playing out here in Australia. I strongly recommend those interested in the subject, to follow the links shown below which provide extensive material on what has been happening.

Further reading material on subjects covered in this article can be obtained at the following locations:

www.ieagreen.org.uk or www.co2captureproject.com/research or West Australian Legislative Council Hansard, Thursday 13th November 2003 Barrow Island Bill 2003

Gorgon Gas Development

Project Type

CO2 Geological Storage Demonstration Project

Project Category

CO2 Storage in Aquifers

Project Status

In Preparation

Project Overview

ChevronTexaco as operator of the Gorgon gas development is planning one of the largest geological CO2 sequestration projects in the world. The development will be based on the Gorgon gas field in Australia which is one of the world’s premier hydrocarbon resources. The gas field is situated 130 km off the north-west coast of Western Australia.

Project Aim(s)

The “Gorgon Greenhouse Gas Management Strategy” reflects the current best practices in greenhouse gas management with major commitments to:

• Incorporate current best practices in thermal efficiency and greenhouse gas emission control where practicable;
• Re-inject separated reservoir CO2;
• Investigate potential synergies with existing Barrow Island oil operations to identify and implement measures that could reduce greenhouse gas emissions (i.e., using associated gas from oil production within the proposed Gorgon gas processing facility to minimise flaring);
• Continue the existing commitment to greenhouse gas related research and development; and
• Pursue potential opportunities for external sale or use of separated reservoir CO2 as a chemical feedstock or enhanced oil recovery agent.



Funding Source(s)

Currently, the estimated capital costs for removing reservoir CO2 from the natural gas is approximately A$ 400 million based on two 5-MTPA LNG trains. The CO2 re-injection system, including compression, pipeline and wells, would require a further capital expenditure of approximately A$300 – $400 million. In addition, there would be operating costs for CO2 removal, re-injection and monitoring.

Overall Project Costs

A$ 400 million Capital cost of removing CO2 from the natural gas.

Project Timescale

Production from the Gorgon gas field is planned to commence in 2008-2010.

Expected Key Deliverables

A re-injection facility to sequester CO2 beneath Barrow Island would be sized to accommodate the full stream of separated reservoir CO2.

Project Links

Further information regarding the Gorgon gas development on Barrow Island and details on Greenhouse gas Management Strategy can be obtained from the Gorgon development website at http://www.gorgon.com.au

Project Summary

The development proposal comprises the establishment of a gas processing facility on Barrow Island, which lies directly between the gas fields and the Australian mainland. Barrow Island has been home to one of Australia’s most successful operating oilfields since 1967 and is also an internationally important nature reserve.

The Gorgon Venture is committed to the effective management of its greenhouse gas emissions. The Gorgon project was the first to conclude a voluntary Greenhouse Challenge Agreement with the Australian Greenhouse Office while still in the design stages of the project. This level of commitment is reflected in the “Gorgon Greenhouse Gas Management Strategy” – developed specifically for the proposed development of the Gorgon gas field.

Integration of the greenhouse gas management strategy into the gas processing facility design – from the early conceptual design phase to plant operation – means that the proposed LNG processing facility on Barrow Island would be the most greenhouse gas efficient facility of its kind in the Asia Pacific region, and one of the most efficient in the world.

Net greenhouse gas emissions are estimated at approximately 3.3 million tonnes per annum (MTPA) of CO2 equivalents. This is based on a reference case of a facility producing 10 MTPA of LNG and 300 terajoules per day of gas for domestic supply. The use of this 10 MTPA of LNG for power production in Asia would reduce global life cycle CO2 equivalent emissions by 30 MTPA compared to coal.

Reservoir CO2 injection
CO2 will be injected into the Dupuy saline reservoir, beneath the north end of Barrow Island. The Gorgon natural gas reservoirs contain naturally occurring CO2 levels of approximately 14 mol% that need to be removed before the gas can be liquefied. The removal is necessary as CO2 would freeze in the LNG process, potentially damaging the equipment. Current standard practice by all operating LNG facilities worldwide is to vent this CO2 to the atmosphere as a concentrated stream.

A re-injection facility to sequester CO2 beneath Barrow Island would be sized to accommodate the full stream of separated reservoir CO2. Re-injection would commence as soon as practicable after the gas processing facilities commissioning and start-up process. All of the studies undertaken to date by the Gorgon Venture indicate that re-injection is technically feasible. The Venture is committed to re-inject reservoir CO2 unless it is proven to be technically infeasible or cost-prohibitive.

The Re-injection Reservoir
Extensive studies were conducted to identify the best location for a CO2 re-injection scheme. Several potential sites were identified. Ultimately the Dupuy saline reservoir under Barrow Island was selected as the best re-injection candidate.

The top of the Dupuy saline reservoir is located approximately 2300 m below Barrow Island. It is approximately 500 m thick at the northern end of Barrow Island and is overlain with a thick shale cap-rock seal. The Barrow Island fault intersects the saline reservoir at the southern end of the Barrow Island. This fault provides a seal to the oil and gas production reservoirs located above the Dupuy saline reservoir.

Several features of the Dupuy saline reservoir that are conducive to CO2 sequestration make it the preferred site for reservoir CO2 re-injection. The CO2 would be injected at depths of between 2700 to 3000 metres into a gently sloping (upwards) reservoir. The pressure in the reservoir will cause the injected CO2 to behave as a super critical fluid with behaviour being more liquid-like which will reduce the density difference between the CO2 and the saline water. Based on the solubility of CO2 at reservoir conditions, the size of the Dupuy saline reservoir theoretically has the capacity to dissolve many times the actual re-injection volumes.

Further Work
The Gorgon Venture has determined where additional assurance on the behaviour of CO2 in the reservoir is required. The work identified is similar to what would be expected for any oilfield or gas field development. The detailed step-by-step work program is designed to: confirm the feasibility of reservoir CO2 re-injection into the Dupuy saline reservoir; and reduce uncertainties to acceptable limits. This will involve acknowledged experts and Australian government specialists.

ChevronTexaco intends to capitalise on its extensive experience in the design, construction and successful operation of CO2 re-injection schemes for enhanced oil recovery. ChevronTexaco already has a strong working relationship with many research bodies around the world studying geological sequestration. In particular, within Australia, ChevronTexaco is a sponsor and participant in the existing GEODISC program as well as the newly created “Cooperative Research Centre for Greenhouse Gas Technologies” (www.co2crc.com.au) which will continue the work of GEODISC.

Date Last Updated

May 2004

Source: International Energy Agency www.ieagreen.org.uk