Underground coal gasification: the ‘nuclear option’ of unconventional energy
Ecologist, 23rd September, 2013
So-called extreme energy – including fracking, coal bed methane extraction and underground coal gasification – is being rolled out with little concern for the environment, leading campaigner, author and engineer Paul Mobbs tells the Ecologist Film Unit
Ecologist: Could you describe some of the different extraction measures we’re seeing rolled out and developed in the UK, including coal bed methane?
Paul Mobbs: There’s a general term we use called extreme energy, and extreme energy is a collection of different technologies which are really beyond any conventional technology that we use. To produce and supply energy. Everybody knows about fracking- it’s always in the news- but fracking isn’t as straight forward as it appears to be. Saying that fracking is an old established technology is like saying a 1920s car is the same as a brand new modern car. It’s completely different. Fracking enables all sorts of things to take place. You can shatter shale to get the gas out now, you can shatter coal seams to get the methane out of the coal. Coal bed methane is sort of like fracking, it’s not quite like shale gas fracking but it’s the same principles involved. The thing about coal bed methane is that you are trying to get the gas out of the coal. And coal is a bit like the duel kettle you use to clean the tap water…it’s a big carbon filter. When you flush the gas out of the coal, all those pollutants which have been filtered out of groundwater for millions of years will come with it. So in some ways, coal bed methane can be considered slightly worse than fracking.
The ultimate, the nuclear option of unconventional gas, is underground coal gasification, that’s where you set fire to coal seems underground. And this a very absurd technology because we don’t really understand how to do it. The idea was dreamt up by Lenin in the 1920s, because he didn’t want Soviet coal miners going underground and being put in danger. So he asked his engineers to come up with a way of getting the energy from of the coal out of the ground. And so they had this wonderful idea, ‘let’s set fire to the coal seams underground’…and they did that from the 1930s….in Britain they trialled it in 3 locations in the 1950s and it all shut down because it had very bad effects. And if we look at the modern trials of underground coal gasification in Australia, three sites, one has just been shut down because it represents an unacceptable risk to the environment. So be it shale gas, which we’ve seen a lot in the media about, coal bed methane which we haven’t seen much in the media, but in places like Australia it’s a very big issue because it’s having a very bad effect on the local communities, and moving to underground gasification which is proposed in Britain and other places around the world.
All of these technologies are taking our need for energy to a whole new level and a whole new level of risk and impact, and economics has just switched a gear. It’s going so hard to try and supply what it needs to grow that any concern about the environment, or human health, or the future generations, has just gone out the window.
Ecologist: In your opinion, can the fracking industry and the companies involved be trusted to protect the environment and minimise the impact in the U.K?
Paul Mobbs: To look at the fracking industry and unconventional gas is very difficult, because you are not comparing like with like. The situation in America is very different to the situation in Australia, which is going to be very different to Britain. The impact on the environment depends on what type of environment you are putting the technology into.
Now we know that technology itself has certain statistical flaws-for every hole they drill, so many of them will go bad, in the first year or the first 10 years. The bigger issue is what are the costs and benefits. Now we are being sold this almost as a sort of a wonderful utopian dream to solve all our energy and economic problems. And will it do that? Are we getting something for the risks that we are creating? The argument will be, ‘no’– Because we are having a much higher impact for every unit of energy we get. It will produce more carbon than existing conventional energy sources. It’ll have a higher polluting impact, both water and air pollution, than existing energy sources. And if we look at the other fringe benefits, yes it might create a lot of employment, but not locally.
These technologies are mostly proprietary- they’re run by big companies, mostly in the US and Australia. They come in, bring in their own staff, stay in hotels for the period they are drilling, and then go away. So if there is any benefit, it is transitory for the local economy, but the impact will be permanent. If we look into more distant future, we are reaching limits to growth, there is very little doubt about that now, and the future sustainability of humanity depends on food, not on abstract energy from oil and gas.
Food is the number one human energy supply, and if we are contaminating natural environment, rendering parts of the environment unusable because of the contamination from processes such as fracking, coal bed methane, then we are going to threaten any idea of long term sustainability. So asking whether they can protect the environment is a very complex question: Because you can give a very quick answer, which is, ‘probably not’, but if you take a longer term answer, looking at where we have to be going in 50 or 100 years’ time, then you have to say that unconventional gas generally is detracting from where we need to be going.
Ecologist: In the future we know that water is going to become a precious commodity and we also know that fracking uses a lot of water. What is your view on that?
Paul Mobbs: Water is quite a big issue with unconventional gas generally. Both the consumption from the technology but also the implications of pollution. The problem we have is that the Environment Agency today looks at groundwater as just a general resource, it doesn’t see it as a precious resource.
So if we look at Lancashire, right above the area/strata that they are fracking, the Bowland shale, there is the Sherwood aquifer, the Sandstone aquifer. It’s slightly salty water, you wouldn’t want to drink it. But if we look to a future where we short of what because of climate change, then sources such as the Sherwood aquifer could be quite important, because it would be easier to clean up slightly salted water than to desalinate seawater. And if that water is contaminated by chemicals from the Bowland shale, because it’s sitting directly above the vertical cracks, the fracking would definitely penetrate the aquifer, if we contaminate that water then we are cutting off a future water source. This is the trouble with this whole project, it’s such a short term venture, that they’re not considering the longer term impacts of the environmental media that they’ll be affecting.
Ecologist: You were speaking earlier about the fact that they use a special mousse in the fracking process, that is derived from a seed in India. Can you describe the knock-on effects that using a product like that is having on an economy like India?
Paul Mobbs: Unconventional gas has many strange impacts that you wouldn’t immediately consider. So, when they do the fracking, put chemicals down the hole, if they were liquid chemicals they’d be diluted by the groundwater and wouldn’t work as well. So what they do is make a mousse, inject lots of gas with the chemicals and the water, to make a sort of foam. They inject that down well because that doesn’t mix with water so readily. And so they add a thickener- guar- a non-toxic food chemical. It’s quite safe, but most of the guar in the world is produced in places like India, and it’s actually the staple protein for a lot of poor people, particularly in northern India. Fracking is taking up so much guar that the price of guar is rising and people in poor communities and places like India are having trouble feeding themselves because the price of food is going up so much. Fracking as a new technology is having lots of strange impacts that is not immediately obvious.
Ecologist: Can the government be trusted to effectively manage the natural gas, and are there [adequete] solutions and environment protection regulations in place? What are your thoughts on the actual technical side of it?
Paul Mobbs: It’s interesting to contrast how we look at fracking, or unconventional gas, with other technologies. We’ve had town gas works since the Victorian era, and they left a long toxic legacy that we only came to appreciate 100 years later. If you look at landfill, the way we started landfilling after the second world war, initially it seemed quite a benign way of getting rid of our rubbish, but in the 1970s and 80s it came back to haunt us. Incineration had much the same effect, and so the problem is that the government doesn’t really understand the technical nature. They see the figures, they see the potential. For them it’s just a way of solving a very unwelcome political problem, which is getting in there and really solving the economic and ecological problems of the country. And, what we are going to get is a rush to do this technology, and a breaking down of all the barriers to enable that to happen. And just with previous generations with technology, they will only appreciate the gravity of what they have done perhaps 10 or 20 years after the event. And they may be doing this with the best will in the world, and they probably are, at the moment they are not looking at the range of evidence. The people they are talking to are in the industry, they’re not taking a wide range of opinion, and they are definitely not consulting with the public. In fact, Cameron gave a speech to the CBI, in which he said, ‘we are going to consult the public less, we are going to stop gold-plating Britain’s laws, and we are just going to get on with it’. Whenever you look at when that’s happened in the past, that’s always been a recipe for a complete governmental mess.
Ecologist: What, in your opinion, is in store for the British countryside if fracking goes ahead?
Paul Mobbs: Fracking is not about cracking rock. Fracking is a whole process that begins with surveying and ends with the long-term legacy of the processes that have taken place. So we start with a piece of countryside that happens to have a certain geological feature underneath. And they come in, they drill one or two holes, frack those holes, and it has not a great effect on the countryside, but the polluting effect is quite great. So if we look at Lancashire, they’ve only fracked a couple of holes, and all the waste in that process has been put into tankers and taken to Davyhulme sewage works near Manchester, the biggest sewage works in Europe, and the waste from the 2 holes overwhelmed the sewage works.
Now one of Cuadrilla’s headaches in Lancashire is finding somewhere that can get rid of all their waste. Which probably means deep injection. They drill another hole in order to pump the waste down it to get rid of it. So they do their exploration, they go away and characterise what resource they have, then they get the money and come back and do the actual development work. And that involves lots and lots of holes, not just one hole or small number of holes that you see with conventional oil and gas. Every quarter to a half a mile, a mile at most if they use directional drilling, you will have a pad. And on that pad they will drill perhaps one to 20 holes. And those holes will go straight down or fan out. In the media we are using J-shaped holes.
In America only half the holes are directional, the other half just go straight down. Which means you have to pack them closer together to exploit the resource, so what the impact will be will depend on whether its vertical or directional drilling. Over a process of perhaps 10 to 15 years, they will come in and start drilling holes. They will come in, clear the ground, make the pad, do the initial development work, then it’ll have to connect up, all these pads are producing gas, so that requires a pipeline from each pad to a central gas processing centre where it’ll connect to the gas network. So it’s sort of like Lancashire where you could end up with hundreds of miles of pipelines being strung all over the county to connect all the pads with the gas processing centre.
If we look at the effect on the countryside, it’s probably not the fracking or the pads, it’s connecting them all with roads, pipelines, and all the destruction that that creates, that is probably going to have the biggest impact on the environment and local people. So when you’ve got the pad in place, connected up, started production, they’re not extracting gas they’re extracting water with gas dissolved in it. Water comes to surface they extract the gas, the gas goes into a pipe, and off to the processing centre. Along with the water you get a very lightweight oil called condensate. When it comes up it’s quite warm. As it cools, the gases condensate and produce a very volatile mixture of hydrocarbons. That is quite valuable so they skim it off and store it in tanks at the site. If you look at the US, where we have the longest history of this, a lot of fires is caused by these condensate tanks. Either because there is a flaw in the tank, or because there’s a spillage, which causes quite a nasty fire. With that will become various toxic problems that you get from oil fires.
The gas itself is contaminated with all sorts of things- heavy metals, particles of sludge- mostly the stuff that comes out is inert, it’s powdered rock. But when you flush the chemicals in to get the stuff out, then you start generating a whole other set of compounds. A lot of people get worried about what they are putting down the hole. Most of those compounds are known, in isolation we know what they do. So a lot of it will be things like hydrochloric acid. If you go to the doctors or the pharmacist and get a verruca treatment, that’s hydrochloric acid- there’s nothing dangerous about it. When you put hydrochloric acid into a coal seam or a very old shale bed, all the old dissolved heavy metals will come out of the matrix and go into solution and they will then go back up the pipe and go to the surface. The issue is, what do you do with that? There will be large quantities of this quite toxic material. Now mostly they will be bundling that stuff up and pumping it underground again. Most of the problems in the US are groundwater pollution and actually the earthquakes and all the other deleterious effects of doing this process don’t really come with the fracking, they come with the waste disposal. The volumes of fluid and the pressure that they are using the pump the stuff away and get rid of it, on a scale is a greater than the fracking itself. And so that could be quite a problematic thing we are storing for the future.
Ecologist: An industry man we spoke to was saying that the methane that they light is natural methane- not in any way related to the fracking. What are your thoughts on this?
Paul Mobbs: If we look at the pollution instants to date, if you look at the Gasland film, they do a drill and get muddy water, do a drill a few days later and you can set fire to your water. That’s a very exceptional case. It might take decades for the pollution to show up from these processes. The thing about groundwater is it moves very slowly. And what they are doing today might only show up in 100 years at the surface.
Now when we come to the gas, the gas from the process, you can tell what is natural methane (formed by the degradation of biological matter- biogenic methane) and you can identify thermogenic methane- that’s the methane that has come from deep rocks that’s been created by geological processes. It’s quite technical balances of isotopes of carbon. And so you can analyse a sample of gas and say, ‘that’s come from the surface, that’s come from deep’. When they’ve looked in situations in the US, where they’ve insisted that it’s shallow methane, all the evidence shows it’s thermogenic methane, it’s methane that’s been forced into the groundwater by the fracking or the coal bed methane processes. It is very different to conventional oil and gas. [With] Conventional oil and gas you make a hole, then you suck, putting pressure […] into the deposit, so you don’t get a movement of contamination into the groundwater. With coal bed methane and shale gas you’re using such high pressures that you are forcing the pollutants out into the groundwater. So you would expect some movement into the environment.
Ecologist: How are the wells made?
Paul Mobbs: What the industry says is that these wells are safe because we use multiple layers of steel casings and then we concrete those to stop the pollution from the works getting into the general environment. Well, that’s not untrue, but it’s not necessarily true. Because the way they drill these holes is that it’s a 5 or 8 inch hole, they drill down, as they go down they put casings into the hole to protect the bore, to keep it circular, but also as they go down they telescope one into the other. So at the top you might have 3 layers, but by the time you go down 1km, you only have one layer of steel casing. As they put casing down they force cement down, and that goes around the outside. The idea is that it fills up the space between the rock and the steel casing in order to prevent movement of contamination. All the evidence is that cementing will fail. Some will fail on the first day. So if you look at the Macondo well that went wrong in the Gulf of Mexico, that was a cement job that failed completely. If we look at the more general types of evidence for a gas well then 1% will fail in the first year and 30% will fail in the first 10 years. That’s a big issue. Because once you drill the holes and you’ve got the contaminants flowing, there’s a risk. You’ve created a pathway for the migration of pollution forever. Even if you cap the hole and cement the hole when you’ve finished, you’ve still got the pathway for migration. If these things can’t be perfect forever then you’ve got the potential for the deep pollution to come to the surface. And of course no human structure can last forever, so ultimately you are creating ways for that deep pollution, particularly the disposal of the pollutants from the process- which tends to be injected deep down into other rock strata- you are creating a pathway for that to come back to the surface.
If you look at a map of Britain, down in the south east, apart from the little bit around Canterbury where the Kent coal field is, the rocks are too young there to do any really big developments. It’s the midlands and up into Yorkshire, south Wales that in the long term you’ll see the most of these developments. And how that’ll take place is a problem because there’s no national guidance, there’s no plan, we have no national plan or standards for how these developments will be carried out. And so by rushing into this the government is lowering the barriers to make this happen without any real idea about what to do when it gets here.