Energy, Resources and the Environment

The Scorpion and the… Trees: Surface mining (im)practical implications

Suzanne Hangx September 16, 2016

Mirny mine, a former open fit diamond mine, now inactive, located in Mirny, Eastern Siberia, Russia. The mine is 525 meters deep (4^th in the world) and has a diameter of 1,200 m, and is one of the largest excavated holes in the world. .
Credit: Jean-Daniel Paris (distributed via imaggeo.egu.eu)

The Scorpion and the Frog. This old tale, which was first documented by the movie Mr. Arkadin by Orson Welles, reports a scorpion that wants to cross a river… and asks a frog for a ride. Embarking on a lose-lose situation, both the frog and the scorpion are doomed in the tale.

Dramatic, this fable severely resembles how humans conduct their quest for resource extraction. Surface mining, a particular type of resource extraction, is devastating. It involves strip mining, open-pit mining and mountaintop-removal mining and accounts for more than 80% of ore mined each year (Ramani, 2012). Surface mining disturbs the landscape and impacts habitat integrity, environmental flows and ecosystem functions; it raises concerns about water (Miller and Zégre, 2014), air and soil quality (Mummey et al., 2002), and often also public health. Legacies of surface mining may include loss of soil structure and fertility, altered hydrology, and long-term leaching of contaminants from tailings and end-pit lakes (Isosaari and Sillanpää, 2010; Li, 2006; Ramani, 2012).

A new study debates the possible routes to deal with the legacies of surface mining. In a first instance, the authors revisit the terms remediation, reclamation, restoration and rehabilitation (R4) and clearly distinguish them in terms of the end-goal. While remediation is a more technical term and aims at removing pollutants and avoiding human exposure to them, restoration proposes the full recovery of the original ecosystem, prior to mining. Although frequently claimed as the end-goal, restoration may often not be feasible because of a myriad of constrictions.

To find out more about how the R4 is differentiated and where surface mining will likely happen in the future, check out the full study by Dr. Lima and her co-workers here.

Dr. Ana Theresa Lima is an Adjunct Assistant Professor at the Ecohydrology group, Department of Earth and Environmental Sciences, University of Waterloo, Canada, and a Visiting Associate Professor at the Department of Environmental Engineering, Universidade Federal de Espirito Santo, Vitória, Brazil. Her research interests include electrokinetics, urban soils and the impact of human activity on them, organic and inorganic pollution and possible remediation techniques, and environmental policy.

References

Miller, A., Zégre, N., 2014. Mountaintop removal mining and catchment hydrology. Water 6, 472–499. doi:10.3390/w6030472

Mummey, D.L., Stahl, P.D., Buyer, J.S., 2002. Soil microbiological properties 20 years after surface mine reclamation: spatial analysis of reclaimed and undisturbed sites. Soil Biol. Biochem. 34, 1717–1725. doi:10.1016/S0038-0717(02)00158-X

Isosaari, P., Sillanpää, M., 2010. Electromigration of arsenic and co-existing metals in mine tailings. Chemosphere 81, 1155–1158.

Li, M.S., 2006. Ecological restoration of mineland with particular reference to the metalliferous mine wasteland in China: A review of research and practice. Sci. Total Environ. 357, 38–53. doi:10.1016/j.scitotenv.2005.05.003

Ramani, R. V., 2012. Surface Mining Technology: Progress and Prospects. Procedia Eng. 46, 9 – 21.

Words on Wednesday: Cobalt, chromium and nickel contents in soils and plants from a serpentinite quarry

ERE Matters May 27, 2015

Words on Wednesday aims at promoting interesting/fun/exciting publications on topics related to Energy, Resources and the Environment. If you would like to be featured on WoW, please send us a link of the paper, or your own post, at ERE.Matters@gmail.com.

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Lago-Vila, M., Arenas-Lago, D., Rodríguez-Seijo, A., Andrade Couce, M. L., and Vega, F. A., 2015. Cobalt, chromium and nickel contents in soils and plants from a serpentinite quarry, Solid Earth, 6, 323-335.

Abstract:

The former serpentinite quarry of Penas Albas (Moeche, Galicia, NW Spain) left behind a large amount of waste material scattered over the surrounding area, as well as tailing areas. In this area several soils were studied together with the vegetation growing spontaneously over them with the aim of identifying the bioavailability of heavy metals. The potential of spontaneous vegetation for phytoremediation and/or phytostabilization was evaluated. The pH of the soils ranges from neutral to basic, with very low organic matter and nitrogen contents. There are imbalances between exchangeable cations like potassium (K) and calcium (Ca), mainly due to high magnesium (Mg) content that can strongly limit plant production. Moreover, in all of the studied soils there are high levels of cobalt (Co), chromium (Cr) and nickel (Ni) (>70, >1300 and >1300 mg kg^-1, respectively). They exceed the intervention limits indicated by soil guideline values. Different soil extractions were performed in order to evaluate bioavailability. CaCl₂⋅0.01M is the most effective extraction reagent, although the reagent that best predicts plant availability is a mixture of low molecular weight organic acids. Festuca rubra, L. is the spontaneous plant growing in the soils that accumulates the highest amount of the metals, both in shoot and roots. Festuca also has the highest translocation factor values, although they are only >1 for Cr. The bioconcentration factor is >1 in all of the cases, except in the shoot of Juncus sp. for Co and Ni. The results indicate that Festuca is a phytostabilizer of Co and Ni and an accumulator of Cr, while Juncus sp. is suitable for phytostabilization.

Extraction efficiency. In each soil, bars with different letters
indicate significantly different EF values (p <0.05) for each
metal. Hanging bars are the standard deviation.

I’m a Geoscientist: Chris Juhlin – President

ERE Matters March 9, 2015

It’s I’m a Geoscientist week! Or more exactly: weeks. From March 9 until March 20, the EGU supports I’m a Geoscientist to help students engage with scientists about real science. The Energy, Resources and Environment Division of the European Geosciences Union encompasses a broad range of different ERE-related topics, from surface to subsurface, spanning all aspects of geosciences. In order to demonstrate how broad the Division actually is, and what you can do as a geoscientist to be involved with energy, resources or the environment, we asked the members of the ERE committee to introduce themselves and explain how their day-to-day work relates back to ERE.

We will kick off with our President Chris Juhlin, Professor in Geophysics at Uppsala University.

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People have mixed feelings concerning large meetings such as the EGU in Vienna or the AGU in San Francisco. It is true that it can be more difficult to get immersed in the science at large meetings compared to small focused meetings and it may also be more difficult to make new contacts with other researchers. However, large meetings offer a wide variety scientific topics and the opportunity for the participant to get acquainted with new fields of research. They are also able to attract leading speakers that can give presentations that leave a lasting impact. I had this experience listening to Jeffery Sachs at the AGU in December 2014. He emphasized many issues that are directly related to research within the ERE division. We need to find solutions that will make the planet sustainable and comfortable for 10 billion people in the near future. This will involve using all our ingenuity in reducing the carbon footprint and management of resources. Although the program is not yet set for the 2015 EGU, I am sure that there will be speakers there that will also inspire us to work for solutions dealing with Energy, Resources and the Environment!

My research related to ERE involves the fields of mining geophysics, carbon dioxide storage and storage of spent nuclear fuel. In addition, I have research interests in scientific drilling and larger scale crustal geophysics.

If the world’s population is to live at an European comfort level then we will need to find numerous new ore deposits. We should not expect that all these deposits should be found outside of Europe. In fact, both from a social standpoint and an economic one, it is in our interest to ensure that we find ore deposits in our own backyard and not rely on the rest of the world to supply us with metals. Currently Europe consumes about 20% of the world’s metals, but only produces about 4% of them. My research in mining geophysics is related to the development of geophysical methods for building of more accurate geological models of the subsurface. This increased accuracy allows ore to be found and extracted with less impact on the environment.

Diagram from the IEA, illustrating the energy consumption in Europe, per energy source.

The world is still heavily dependent upon on fossil fuels for electricity production, heating and transport. In addition, many industrial processes generate large amounts of carbon dioxide that are released into the atmosphere, for example steel production. Although there is an accelerating trend to increased use of non-fossil fuels for electricity production, heating and transport we will most likely remain highly dependent on fossil fuels for the rest of the century. If Europe is to reach zero carbon emissions by 2050 then geological storage of carbon dioxide is necessary. My research involves development of seismic methods for monitoring the carbon dioxide in the sub-surface to ensure that it remains there after injection. I am also involved in initiating a pilot project for testing various aspects of carbon dioxide storage in Sweden.

Nuclear energy is a near-zero carbon emission technology that accounts for about 18% of the electricity generated within the OECD (see the Figure). It has many advantages over fossil fuel energy, but there are also challenges in using it as most recently evidenced by Fukushima in 2011. In addition, the spent fuel rods need to be stored safely for on the order of 100 000 years. My research involves using seismic methods to locate rock that has the potential to store the spent fuel safely. My own country, Sweden, along with Finland are furthest along in the world in building permanent storage facilities. These facilities will also require the use of geophysics to monitor the sites in the initial stages of storage.

Words on Wednesday: Environmental soil quality index and indicators for a coal mining soil

ERE Matters February 25, 2015

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Masto, R. E., Sheik, S., Nehru, G., Selvi, V. A., George, J., and Ram, L. C.: Environmental soil quality index and indicators for a coal mining soil, Solid Earth Discuss., 7, 617-638, doi:10.5194/sed-7-617-2015, 2015

Abstract:

Assessment of soil quality is one of the key parameters for evaluation of environmental contamination in the mining ecosystem. To investigate the effect of coal mining on soil quality, opencast and underground mining sites were selected in the Raniganj Coafield area, India. The physical, chemical, biological parameters, heavy metals, and PAHs contents of the soils were evaluated. Soil dehydrogenase (+79%) and fluorescein (+32%) activities were significantly higher in underground mine (UGM) soil, whereas peroxidase activity (+57%) was higher in opencast mine (OCM) soil. Content of As, Be, Co, Cr, Cu, Mn, Ni, and Pb was significantly higher in OCM soil, whereas, Cd was higher in UGM. In general, the PAHs contents were higher in UGM soils probably due to the natural coal burning in these sites. The observed values for the above properties were converted into a unit less score (0–1.00) and the scores were integrated into environmental soil quality index (ESQI). In the unscreened index (ESQI-1) all the soil parameters were included and the results showed that the quality of the soil was better for UGM (0.539) than the OCM (0.511) soils. Principal component analysis was employed to derive ESQI-2 and accordingly, total PAHs, loss on ignition, bulk density, Be, Co, Cr, Ni, Pb, and microbial quotient (respiration: microbial biomass ratio) were found to be the most critical properties. The ESQI-2 was also higher for soils near UGM (+10.1%). The proposed ESQI may be employed to monitor soil quality changes due to anthropogenic interventions.

Environmental soil quality index of opencast and underground mine soils by (a)
unscreened transformations, and (b) principal component analysis based index