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Mine tailings influencing soil contamination by potentially toxic elements

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The potentially hazardous contents of mine tailings can pose a serious threat to the environment. Tailings dispersed around the abandoned Monica mine (Bustarviejo) in the Autonomous Region of Madrid (Central Spain) were studied to determine the concentration of several potential toxic elements and their geochemical impact in the surrounding soils. A total of 17 surface soil samples were collected from both mixed sulfide mine tailings sites and unmined soils, within a radius of 1900 m from the mine entrance. The processing of minerals (basically arsenopyrite, matildite and sphalerite) produced tailings with a pH as low as 2.9. Elements such as As, Cu, Zn, Cd, Pb, W, Ag, Fe were found in very high concentrations, contaminating the soil to varying degrees (these elements were sometimes 10- to 20-times higher in the tailings than in the unmined soils). Given its short distance and accessibility from such a large city as Madrid, it is of undeniable environmental and educational interest. Among other factors, there is a need for improvements to tailings management strategies.
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ORIGINAL ARTICLE
Mine tailings influencing soil contamination by potentially toxic
elements
Rosario Garcı
´a-Gime
´nez
1
Raimundo Jime
´nez-Ballesta
1
Received: 4 November 2015 / Accepted: 24 December 2016 / Published online: 2 January 2017
ÓSpringer-Verlag Berlin Heidelberg 2016
Abstract The potentially hazardous contents of mine
tailings can pose a serious threat to the environment.
Tailings dispersed around the abandoned Monica mine
(Bustarviejo) in the Autonomous Region of Madrid (Cen-
tral Spain) were studied to determine the concentration of
several potential toxic elements and their geochemical
impact in the surrounding soils. A total of 17 surface soil
samples were collected from both mixed sulfide mine
tailings sites and unmined soils, within a radius of 1900 m
from the mine entrance. The processing of minerals (ba-
sically arsenopyrite, matildite and sphalerite) produced
tailings with a pH as low as 2.9. Elements such as As, Cu,
Zn, Cd, Pb, W, Ag, Fe were found in very high concen-
trations, contaminating the soil to varying degrees (these
elements were sometimes 10- to 20-times higher in the
tailings than in the unmined soils). Given its short distance
and accessibility from such a large city as Madrid, it is of
undeniable environmental and educational interest. Among
other factors, there is a need for improvements to tailings
management strategies.
Keywords Mine soils Trace elements Soil pollution
Enrichment factor Environment Madrid region
Introduction
Mining operations produce waste material after the min-
erals of interest have been extracted. Such waste materials,
known as mine tailings, can often contain high concen-
trations of potentially toxic material.
As a result, changes in soil morphological, physical and
chemical properties can occur, leading to severe soil damage.
Moreover, the mining industry produces enormous quanti-
ties of fine-rock particles, ranging in size from a grain of sand
to a few micrometers (USEPA 1994). Vegetation can also be
affected with the destruction of extensive areas.
Different risks have been associated with mine tailings:
instability, visual impact, contamination of the water table,
acid-mine drainage (AMD) and secondary mineral sedi-
mentation (Grangeia et al. 2011; Bini 2012; He-rong et al.
2015;Muetal.2015). Potentially toxic trace elements
(PTEs) dumped in high concentrations nearby abandoned
mines represent long-term health hazards, as these mine-
waste materials percolate into nearby soils (Conde et al.
2008; Martı
´n Peinado et al. 2015; Abreu et al. 2016;
Martı
´n-Moreno et al. 2016). They can go on to contaminate
land, sub-soil and food crops, causing loss of biodiversity,
posing an important risk to human health (Lee et al. 2009;
Rodriguez et al. 2009; Ferna
´ndez-Caliani et al. 2009;
Conde et al. 2008), and even causing fatal diseases in
humans through crops and water (Lee et al. 2007).
Soils formed on landscapes altered by mining constitute
the mine soils and can be classified as either Entisols or
Inceptisols (Sencindiver and Ammons 2000; Angel et al.
2008), with few or no natural genetic horizons (Soil Survey
Staff 2006). Normally, these very young soils have their
origin in fragmented rock mixed with fine earthy material.
Their soil profiles are irregular and are mixed or substituted
by earthy materials from lower depths.
&Raimundo Jime
´nez-Ballesta
raimundo.jimenez@uam.es
1
Department of Geology and Geochemistry, Universidad
Auto
´noma, Madrid, Spain
123
Environ Earth Sci (2017) 76:51
DOI 10.1007/s12665-016-6376-9
Content courtesy of Springer Nature, terms of use apply. Rights reserved.
... Sulphidic tailings represent the majority of stored tailings in Europe that can pose serious environmental problems, from acid mining drainage (AMD) [1] to soil contamination [2], if not managed properly. At the same time, tailings still contain valuable metals and critical raw materials (CRMs) that are of importance to the European market of raw materials. ...
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... Tailings are transported by wind, precipitation, and runoff water and deposited in both terrestrial and aquatic environments. As a result, areas near mining facilities could show elevated concentrations of toxic metals in topsoil (García-Giménez & Jiménez-Ballesta, 2017;Schuh et al., 2019), water (Kumar et al., 2021;Palmer et al., 2021;Shaw et al., 2011), and river sediments (Clark et al., 2021;Sánchez-Donoso et al., 2021;, raising concern about contaminating habitat and food webs (Nawab et al., 2015;Wang et al., 2021;Xiao et al., 2008). ...
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... O'Kiep is affected by MSW that were left without rehabilitation. Different risks associated with such mining activity include ARD, contamination of the water table and secondary mineral sedimentation (García-Giménez and Jiménez-Ballesta, 2017;Coetzee et al., 2010). High concentrations of PTEs from the nearby CMM represent a continuing human health challenge and environmental hazard as the MSW, including by-products, can leach into soil and groundwater (Martín-Moreno et al., 2016;You et al., 2015). ...
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Book
Trace elements occur naturally in soils and some are essential nutrients for plant growth as well as human and animal health. However, at elevated levels, all trace elements become potentially toxic. Anthropogenic input of trace elements into the natural environment therefore poses a range of ecological and health problems. As a result of their persistence and potential toxicity, trace elements continue to receive widespread scientific and legislative attention. Trace Elements in Soils reviews the latest research in the field, providing a comprehensive overview of the chemistry, analysis, fate and regulation of trace elements in soils, as well as remediation strategies for contaminated soil. The book is divided into four sections: • Basic principles, processes, sampling and analytical aspects: presents an overview including general soil chemistry, soil sampling, analysis, fractionation and speciation. • Long-term issues, impacts and predictive modelling: reviews major sources of metal inputs, the impact on soil ecology, trace element deficient soils and chemical speciation modelling. • Bioavailability, risk assessment and remediation: discusses bioavailability, regulatory limits and cleanup technology for contaminated soils including phytoremediation and trace element immobilization. • Characteristics and behaviour of individual elements. Written as an authoritative guide for scientists working in soil science, geochemistry, environmental science and analytical chemistry, the book is also a valuable resource for professionals involved in land management, environmental planning, protection and regulation.