Debate on fracking or hydraulic fracture

2014/04/01 Galarraga Aiestaran, Ana - Elhuyar Zientzia Iturria: Elhuyar aldizkaria

• Ingurumena
• Energia
• Hidrologia
• Geologia

Javier Arostegi: Before explaining the technique it is necessary to know that rock deposits containing hydrocarbons are of two types: conventional and unconventional. In conventional warehouses, hydrocarbons are trapped in the pores and cracks of the rocks, and these pores and cracks are joined together, they are porous and permeable rocks. Therefore, if a survey is carried out, runoff, whether liquid or gaseous, is poured spontaneously outside, since it is at high pressure in the warehouse. It's like when we make a hole in the beach: as the water that fills the hole is removed, water is formed in the hole, since the pores that store the water are joined together.

On the other hand, there are extraordinary warehouses. In these deposits, the hydrocarbons are found in the pores of the rocks and in small cracks, but in comparison with the previous ones, the pores are not united, they are not permeable. Therefore, in the case of a well being carried out, only the existing hydrocarbon will be extracted at the site of the survey, avoiding the discharge of the rest. Precisely for this purpose, hydraulic fracture is used to connect pores and cracks, which allows to increase the efficiency of extraction.

By the way, these extraordinary deposits are actually stem rocks that produce hydrocarbons. In conventional warehouses no hydrocarbons are produced, but they are formed in mother rocks that migrate over time and are trapped in porous rocks, that is, in conventional warehouses. In the extraordinary deposits are located in the same place where the hydrocarbons, in mother rock, have been produced.

J. A . : That is. In the hydraulic fracture, a survey is carried out to the depth in which the hydrocarbon is found and water is introduced to pressure to break the rocks and join pores and cracks. In this way, the gas flows into the well and is collected.

From approximately 2005, this technique began to be used with new variants. Thus, in each survey, a hydraulic fracture occurs intermittently. It is called multi-stage. In addition, from a single surface platform several surveys are made, around 4-10 in horizontal, in different directions. This allows to increase the exploited surface and improve extraction.

In order for the water to break the rocks, the tube must first be drilled. This is done through small explosions. In this way, holes are created in the pipe through which the water comes out at high pressure to crack the rocks.

The water contains a series of mixed substances. Approximately 5% that is injected is sand, whose mission is to prevent the closure of fissures. In addition to the sand, it contains other substances to increase the effectiveness of the procedure, such as the viscosity modulators for the sand to flow properly, the anticorrosive ones to avoid the oxidation of the tubes, the biocides so that the bacteria do not consume hydrocarbons and produce hydric sulphur that would damage the quality of the gas, the hydrochloric acid to help the break of rocks, the lubricants to protect the tubes, the regulators of tension.

Itxaso Arostegi: I think that at the core of this interest is our dependence on hydrocarbons. Our society is based on energy consumption, both for the production and purchase of food and for the obtaining of the rest of material goods. And 80% of this energy comes from hydrocarbons. We must take into account that we are reaching the peak of oil and gas, and to this they intend to give solution by exploiting unconventional hydrocarbons through hydraulic fracture.

J. A. A. That is. The extraction ceiling is called a peak of hydrocarbons, that is, the moment in which more is extracted. From there, to get what was extracted until then, more and more energy will be needed.

T. T. A. A. Not only that, but it is expensive, since what is left is more difficult to extract.

J. A. A. For example, extraction at sea is more costly than on the ground. For this reason, once reached the peak of hydrocarbons, it will be necessary to invest more to maintain production, which in some case will be economically unsustainable.

T. T. A. A. However, it is estimated that hydrocarbon reserves, including those existing in extraordinary deposits, and following the current rate of extraction, will be exhausted for the period 2040-2050.

J. A. A. Somewhere yes. Resources are not infinite, much less fossil resources. And if we take into account that consumption increases…

T. T. A. A. To maintain this consumption and stop the descent that comes after the summit, they have to look for other ways. And one of them is the extraction of gas that until now was not exploited by hydraulic breakage.

T. T. A. A. It depends on the scale: on a larger scale, greater ease of use of this technique. In November 2012 the European Parliament issued an illegal resolution to lay the first stone of the hydraulic fracture regulation. In principle it does not regulate it, it only says that the member countries of the European Union will regulate the use of hydraulic fracture.

The European resolution does not prohibit hydraulic fracture, but it does impose a number of conditions such as compliance with environmental protection and safety legislation.

J. A. A. Little specific, it only provides general guidelines.

T. T. A. A. So it is. In any case, it makes it very clear that it is the responsibility of each country to establish a regulation for the extraction of gas from extraordinary deposits. At the state level there are two milestones. One, the Law of 29 October 2013, of electric supply, and although it seems that it has nothing to do with hydraulic fracture, refers to the technique and foresees its use. Somehow it opens the door. It does not regulate, modifies the hydrocarbon law and introduces an article saying it authorizes the technique.

The other, of 9 December 2013, concerning the assessment of environmental impact, clearly points out that hydraulic fracture should follow the same environmental impact assessment procedures as other projects.

At the community level we have Law 2/2013, of 10 October, which modifies Law 16/1994, on Conservation of Nature. It has a single article, but it regulates extractive activities in its two sections, third and sixth. One of them is hydraulic fracture. But it only regulates them in protected natural spaces. For example, in the third part says (sic. ): "When these activities are compatible with the environmental values that are protected, the projects of extractive activities in protected natural spaces must submit, in their entirety, to the evaluation of an individual environmental impact that is necessary for both the extraction and the facilities. This evaluation should include all restoration work to the previous situation and the recovery of existing environmental values."

And in the sixth says (sic. ): "the modification of the plan will establish the adequate morphology of ecosystems and the landscape recovery measures that the owner of the farm must present in the restoration plan as special conditions for the authorization".

However, it only affects the extractive activities that are developed in the protected natural spaces, without regulating the rest of the areas.

We must also mention what happens at the local level. And it is that, as the area approaches, the opposition to hydraulic fracture increases and, at the local level, many municipalities have renounced this technique. In principle, the statements of the municipalities do not have legal value, but serve to show the opinion of the citizenship.

J. A. A. Two wells were about to probe in Vitoria, specifically in the area of Subijana, but have not been excavated. Otherwise, both in the past and in the present, the greatest interest in the use of this technique is found in a broad research authorisation: Gran Enara.

This authorization covers a good part of Álava and part of Castilla y León. The Association of Hydrocarbons of Euskadi is the entity interested in the realization of surveys and the use of hydraulic fracture. Thus, several points have been proposed for the realization of the surveys, which for a different reason have been changing. For example, in Subijana, the Vitoria-Gasteiz City Council denied activity licenses.

Environmental impact assessments are currently being carried out and these studies are forwarded to the ministry pending approval. These are prospecting surveys. In the last legislature, those of the Basque Government came to say that in the authorization of Gran Enara there were 185,000 million cubic meters. Well, that's a lot. To know its availability, prospecting surveys are necessary.

In addition to this authorization, there are twelve other permits in different phases of investigation throughout Euskal Herria sur.

J. A. A. Although we have no experience here, in the United States they have been using this technique for years and we know the risks involved. As for the environmental risks, first of all there is the risk of contamination of underground water, aquifers. It must be taken into account that both the substances that transport the injected water and the gas itself can contaminate the water.

It is true that current technology has measures to avoid it, such as well coatings, the pipes used, etc. They are technically good, they are well isolated. However, the risk never completely disappears. Some experts, for example, point out that between 1% and 2% of the wells can present defects.

Another factor to take into account is the distance between the gaseous layer and the aquifer, at greater distance, logically, greater risk of contamination.

On the other hand, a prospecting survey is not an exploitation. In the farms there are a lot of surveys, one next to the other, and what happens in one can affect another.

In addition to the risk of contamination of aquifers, water consumed by the technique is found. The water required for each survey is 20,000 cubic meters, and water systems already suffer high stress due to droughts, excessive consumption, etc. Hydraulic fracture would increase stress.

Besides the underground water there is a water management that leaves the well. In fact, 50% of the water that enters the well leaves outside and must be managed. The water is abundant and the water is contaminated, both by the added substances and by the gas. It must be taken into account that, together with water and sand, for each survey 100,000 liters of substances are injected, some of them with high contaminating capacity and whose use is not totally transparent. This water is collected in tanks or outdoor ponds and is taken to the treatment plant. But it is not easy, it is a big volume. I do not know if we are prepared for it. Nor will we refer to possible accidental spills. In addition to the aforementioned, there is a seismic risk.

J. A. A. In principle, although the intensity of the microearthquakes generated as a result of the surveys is low, it cannot be ruled out that a microseism produced in one place causes a greater sexism in another. The area they want to probe in Álava is not psychically as unstable as the Leitza area in Navarre or the Pamplona fault, but the risk is not insignificant. The problem is induced seismicity: microearthquakes can cause a crack or a weakness that suffers a tectonic stress to come into play.

In addition, there is an impact on the soil. In my opinion, perhaps that is the most significant impact. An exploitation of this type occupies a huge surface. If it is true that there are as many gases as Gran Enaran says, it means that thousands of polls will have to be carried out in Alava, thousands of polling platforms.

T. T. A. A. And each survey platform needs its own infrastructure.

J. A. A. Yes, yes. That is why I think that the surface it occupies should be discarded. It is totally contemptible. Note that both platforms occupy approximately one square kilometer. Well, they would have to do thousands of these things, since the exploitation of gas only allows to extract the gas from a small area of each.

T. T. A. A. This would mean the loss of land suitable for agriculture. And infrastructure would have to be done for vehicles.

J. A. A. A survey requires 3,000 truck trips. Heavy trucks.

T. T. A. A. Despite the new infrastructures, the current ones would be saturated. And we all know how transport affects air pollution. On the other hand, natural gas and unconventional gas are cleaner than oil or other hydrocarbons, since when burned they do not release so much greenhouse gas. In these calculations, however, the fused gas is not correctly introduced, and in the probes a lot of gas is emitted directly into the atmosphere.

In particular, if the greenhouse gas that is emitted into the atmosphere determines what type of hydrocarbon is the least polluting, it will have to take into account the gas emitted during the whole process, not only the one that is burned at the end. However, many times, in calculations, the whole process is not contemplated. It cannot be denied that extraordinary gas when burning is cleaner than oil, and let's not say if we compare it to coal. But if we take into account the gas that escapes in extraction, it is not as clean as it is said. It is technically considered a cleaner extraction when methane emissions are, approximately, less than 3%. Well, in some reliable research, some farms have measured emissions of 4-9%.

J. A. A. The starting point is that we need gas. Approximately 42% of the energy we consume in the Community is gas, and everything comes from the outside. But if we managed to remove the gas we have underground, it would not be the panacea.

J. A. A. Yes, yes. It seems that there are those who are convinced that the gas of the extraordinary deposits will compensate for the decrease of the hydrocarbon reserves. In addition, they say jobs will be created, I don't know what benefits it gives... And that is not at all true. The question must be seen with prudence. In fact, the cost of a conventional survey is about 7 million dollars. Well, for the well to be profitable, a thousand cubic feet should cost at least 5 dollars in the mouth of the well. And in the United States it is trading at 3.5 dollars.

T. T. A. A. That is, it is selling below what costs, because it receives subsidies. And that cost of 5 dollars is also in the mouth of the well; it is actually more expensive, since transport and distribution increase its cost, and to be profitable the marketing price should be 7 to 9 dollars.

J. A. A. In addition, reservations are being expanded. The Energy Information Administration, the EEA, has already lowered the forecasts of abnormal gas and not a few, at least half. The jobs are also inflated and, in addition, they do not say that there are jobs that are lost.

T. T. A. A. For example, in agriculture, in tourism...

J. A. A. Everything is very inflated. Normal: They must attract investors to put money to extract gas. And at the same time they do not say that there are companies that extract gas that have touched bottom. That's trying to escape forward, but it's a bubble. Take Accounts: In the United States, the verified reserves do not think they will be for more than 20 years, and in Europe the forecasts are even smaller, since the geological basins here do not have measures of the great ones. And here the population density is greater and also the environmental awareness. Then, here are other conditions for hydraulic fracture.

T. T. A. A. The first thing is to lower consumption, go towards another society. And then, energy savings and the improvement of energy efficiency are fundamental. According to the prestigious consulting firm McKinsey, by 2030 it is possible to improve efficiency by 30%.

J. A. A. But what happens? They say it is essential to investigate the hydraulic fracture; that we cannot renounce to know to what extent we have reserves under our plot. Okay, the information is never bad. But why do we stop investigating to improve efficiency knowing that we have a 30% margin of improvement in efficiency and savings? For that is forgotten. Because what we invest in the research of hydraulic fracture we do not invest in saving and improving efficiency. Therefore, the investment in hydraulic fracture implies a delay in the other field.

T. T. A. A. The third step would be the development of renewable energies, which requires large investments. Yes, if we continue the way so far, what would be obtained from renewable energy sources would not be enough to cover the demand. In fact, after extrapolation, we would need for 2035 a 50% more energy than we currently consume. Therefore, the first measure should be the reduction of consumption, followed by the improvement of efficiency and the development of renewable sources. However, instead of giving priority to it, there has been something else, which means a total delay. And the more it is delayed the more traumatic the adaptation will be.

J. A. A. Because we need to adapt to another situation. This is sure, since the current one will end. In view of this, we must think about the deadline for which we plan our energy future. Are we planning it for 10 years? I think we have to plan in the long term. We must manage resources efficiently so that future generations will live. And, of course, resources are limited and, in addition, their exploitation has environmental consequences. Therefore, as it is delayed, the damage will be greater and the adaptation will be harder.

T. T. A. A. There is no other alternative: from a globalized economy we have to go towards a smaller economy.

J. A. A. In fact, in these scales, the efficiency in the management of resources and savings is easier.

T. T. A. A. In addition, it must be taken into account that in some uses, at present it is very difficult to replace hydrocarbons. And within hydrocarbons, not all serve for everything. For example, aircraft burn oil and can't be replaced by gas. To prioritize future planning and transition towards society based on other sources of energy, we must also take into account these kinds of things.

J. A. A. That is, and look in the long run and manage with a 50 year vision the resources: gas, oil, coal... And, meanwhile, researching and pushing for the transition. There is no more.