C.R. Cánovas

C.R. Cánovas
Universidad de Huelva | UHU · Departamento de Geología

PhD in Earth Sciences

About

91
Publications
12,169
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2,611
Citations
Citations since 2016
61 Research Items
1751 Citations
20162017201820192020202120220100200300
20162017201820192020202120220100200300
20162017201820192020202120220100200300
20162017201820192020202120220100200300

Publications

Publications (91)
Article
This study deals with the potential release of metal/loids from sulfide mine wastes upon weathering and the health risks associated with their accidental ingestion. To address this, a complete chemical and mineralogical characterization of a variety of sulfide mine wastes was performed alongside a determination of metal/loid bioaccessibility throug...
Article
Full-text available
Rare earth elements (REEs) or lanthanides are often found together in nature, and they are used in multiple anthropogenic activities from green energy and medical technologies to telecommunications and defense systems. However, the current understanding on the concentration and behavior of REEs in oceans and marine organisms is limited, and no regu...
Article
This study investigates the behavior of Tl in the Ría de Huelva (SW Spain), one of the most metal polluted estuaries in the world. Dissolved Tl concentration displayed a general decrease across the estuary during the dry season (DS); from 5.0 to 0.34 μg/L in the Tinto and Odiel estuaries, respectively, to 0.02 μg/L in the channel where the rivers j...
Article
Opencast mining of sulfide ore deposits may lead to the formation of anthropogenic acidic lakes with highly polluted waters. In these systems, it is crucial to understand the hydrological connections between surface and groundwater and their contribution to the pollutant load delivered to the downgradient streams. This study characterizes the inter...
Article
Full-text available
Northern Sweden has been the object of intense metal mining in the last decades producing several water-filled open-pits, or pit lakes. Most of these pit lakes have been limed to maintain a good water quality and to prevent generation of acidic water that could leach the exposed rocks and release metals into water. The aim of this work was to exami...
Article
A phosphogypsum stack located in SW Spain releases highly acidic and contaminated leachates to the surrounding estuarine environment. Column experiments, based on a mixture of an alkaline reagent (i.e., MgO or Ca(OH)2) dispersed in an inert matrix (dispersed alkaline substrate (DAS) technology), have shown high effectiveness for the treatment of ph...
Article
Acid mine drainage (AMD) due to the mining of sulfide deposits is one of the most important causes of water pollution worldwide. Remediation measures, especially in historical abandoned mines, require a deep knowledge of the geochemical characteristics of AMD effluents and metal fluxes, considering their high spatial and temporal evolution, and the...
Article
Acid mine drainage (AMD) contains rare earth element (REE) concentrations several orders of magnitude higher than those of the rest of natural waters and could be a secondary source of REEs. In arid to semiarid climates with a long dry season, the precipitation of efflorescent sulfates constitutes a transient storage of REEs. The REE partition amon...
Article
Sulfide-mining wastes may lead to severe environmental and human health risks, especially challenging in abandoned mines without environmental regulation. This work is aimed at discussing the environmental problems associated to this type of wastes, the risks posed by metal(loid) exposure to living organisms, as well as the measures available to mi...
Article
Acid Mine Drainage (AMD) generates a great concern worldwide due to its severe affection to water resources during hundreds and even thousands of years after the cessation of mining activity if control measures are not implemented. AMD treatment is an environmental necessity, but also constitute a tremendous opportunity for the valorization of pote...
Article
The optimization of the dispersed alkaline substrate (DAS) technology was investigated to achieve the treatment of highly acidic and polluted effluents from a phosphogypsum pile in an orphan site of SW Spain. This phosphogypsum disposal area is located on the Tinto river marsh soils, where it acts as a source of pollution for the estuarine environm...
Article
This paper tries to analyse the technical and economic performance of a full-scale passive Disperse Alkaline Substrate (DAS) treatment plant steadily operating for 28 months (840 days) to treat extremely acidic and metal rich mine waters in the Iberian Pyrite Belt (SW Spain). For the first time, an economic evaluation of this technology and its com...
Article
This paper addresses the behaviour of several technology critical metals (TCMs), i.e., rare earth elements (REEs), Y, Sc, Ga and Tl, in the Tinto River (SW Spain), quantifying their fluxes to the Atlantic Ocean and unravelling the governing geochemical processes controlling their solubility. To accomplish this goal, a high-resolution (2–24 h) sampl...
Article
This study focuses on the search for a sustainable treatment and metal recovery system for acid discharges from a fertilizer industry in SW Spain. The methodology proposed involves the addition of two types of alkaline materials (an industrial waste and a commercial reagent) to neutralize the acidity and remove dissolved elements. In the first case...
Article
The failure of the tailing dam at the Aznalcóllar mine (SW Spain) in 1998 released ≈ 6 million m3 of pyrite sludge and acidic waters, and caused an enormous environmental disaster in the Agrio and Guadiamar rivers. A small aquifer formed by recent alluvial materials deposited by both rivers was also affected. The mine closed as a result of the spil...
Article
Full-text available
A pit lake arises as a consequence of anthropogenic activities in opencast mining areas. These water bodies may be enriched in hazardous stable contaminants and/or in naturally occurring radionuclides depending on the local geological conditions. Mining legacy in Sweden produced hundreds of these pit lakes and most of them are used for recreational...
Chapter
Acid mine drainage (AMD) is a worldwide problem generated by oxidation of metal sulfides, which causes the generation of acidic and metal‐rich solutions. The strong water‐rock interaction processes observed during sulfide oxidation lead to the release of high concentrations of sulfate (up to hundreds of g/L) and pollutants such as Fe, Al, and As (f...
Article
Full-text available
Natural radioactivity in the environment is a field gaining more attention in last decades. This work is focused on the study of natural radioactivity complemented with elementary characterization at former non-uraniferous mining areas in Sweden. This aim is addressed through the study of mining lakes, called pit lakes, which are water bodies gener...
Article
Metal pollution in estuaries represents a serious environmental challenge, especially in areas affected by industrial and mining activities. This study investigates the metal partitioning and availability of rare earth elements (REE), Y and other trace metals (Ag, Tl, U and Cs) in the Ria of Huelva estuary (SW Spain), strongly affected by mining an...
Article
Full-text available
The Río Tinto, located in the Iberian Pyrite Belt (SW Spain), constitutes an extreme case of pollution by acid mine drainage. Mining in the area dates back to the Copper Age, although large-scale mining of massive sulfide deposits did not start until the second half of the 19th century. Due to acidic mining discharges, the Río Tinto usually maintai...
Article
This work deals with the distribution of rare earth elements (REE) in the abandoned Tharsis mines under different hydrological conditions. High concentrations of REE were observed; mean value of 1747 μg/L. The highest concentrations of REE were recorded during the dry period (DP, mean of 2220 μg/L) due to high evaporation and strong water-rock inte...
Article
This study deals with the metal partitioning and bioavailability of metal/loids in the estuary Ria of Huelva (SW Spain) which is strongly affected by historical mining and industrial activities. To address this issue, traditional (i.e., grab samples) and passive sampling (i.e., diffusive gradient in thin films, DGTs) was carried out in the outer pa...
Article
The Tharsis mine is presently abandoned, but the past intense exploitation has left large dumps and other sulphide-rich mining wastes in the area generating acid mine drainages (AMD). The main goal of this work is to study the effect of hydrogeochemical processes, hydrological regime and the waste typology on the physicochemical parameters and diss...
Article
Efflorescent sulfate salts constitute a transient storage of acidity and metals during the dry season in mining areas affected by acid mine drainage, especially under semiarid climates. The main goal of this work was to study the metal partitioning among the dissolved and solid phases through the evaporative precipitation sequence of extremely meta...
Article
Carbon capture and storage (CCS) is the third contributor to cumulative carbon emission reductions required by the second half of this century. Although this is a promising technology for reducing atmospheric CO2, it is only affordable if the confinement of the gas is guaranteed for hundreds of years. Hence, it is of paramount importance to figure...
Article
Extensive extraction of technology critical elements (TCEs) from the lithosphere and their use results in a growing dispersion and remobilisation of these elements within the environmental compartments. We investigated the concentration and mobility of different TCEs (rare earth elements (REEs), Sc, Y, Ga and Tl) in acid mine drainage (AMD) outflow...
Conference Paper
Full-text available
Flood events may play a key role in the metal transport fluxes from rivers to oceans. This is especially relevant in semi-arid and arid climate regions, which alternate long drought periods and short but intense rainfall events, when most of the water discharge, dissolved contaminants, and suspended matter transport occurs. This study provides info...
Conference Paper
Full-text available
The acidic and metal rich waters of the Odiel and Tinto rivers flow into the Huelva Estuary (SW Spain), where mixing with seawater take place. During these mixing processes intense precipitation of Fe and Al in the fluvial domain of the estuary is observed. Hence, a buffer at pH ranges between 3 and 5.5 is observed, although the spatial location of...
Article
In May 2017, a spill from La Zarza pit lake (SW Spain) resulted in the release of approximately 270,000 m3of extremely acidic waters to the Odiel River. Around 780�103kg of Fe, 170�103kg of Al, 2.15�103kgof As and high amounts of other trace metals and metalloids were spilled. The purpose of this study is toexplain the causes, consequences and impa...
Article
Historical mining activity in the Iberian Pyrite Belt has left a huge number of abandoned sites; these cause severe water pollution by acid mine drainage, for which remediation seems to be unaffordable. Although the choice of remediation systems is usually dictated by technical and economic factors, the sustainability of such systems is becoming in...
Article
This research evaluates the feasibility of an alkaline treatment system for highly acid leachates from a phosphogypsum stack located in an estuarine environment degraded by such pollution. The presented methodology consists of the addition of a Ca(OH)2 solution to the different types of phosphogypsum-related acidic leachates with the aim to increas...
Article
Opencast mining operations frequently lead to the creation of large voids that become anthropogenic lakes when the water table recovers. In the case of sulfide mining the stored water is of an acidic nature with significant concentrations of toxic metals and, therefore, a high pollutant potential. The main goal of the present work is to characteriz...
Article
The cementation complex of Las Viñas (SW Spain) is a partially reclaimed abandoned mine site located in the drainage basin of a water reservoir currently under construction. The aim of this investigation was to analyze these mine soils to evaluate their potential environmental impact, especially on the final reservoir water quality. Results evidenc...
Article
Mining residues management is one of the greatest challenges for mining companies around the world. The increasing consciousness of the general public and governments about the potential threat that those residues can pose to the environment is demanding consistent and precise methodologies for assessing the potential release of toxic metals. On th...
Article
Total and dissolved rare earth elements (REE) were studied in a river reach affected by several inputs of acid mine drainage. The first four acidic discharges were of lesser importance compared to the last (Agrio River, coming from the Río Tinto mines), which transported high loads of Fe and Al (2.1 and 4.2 ton/day, respectively) together with REE...
Article
This study aims to characterize geochemically the acid mine drainage (AMD) sources causing deterioration of the water quality of a river reach with extreme hydrologic variability and to identify the patterns of dissolved and particulate contaminants along the reach. The hydrochemistry of the river reach is exposed to dramatic seasonal and spatial c...
Article
Sulfate reduction and its associated contaminant immobilization in marsh soils supporting a phosphogypsum stack was examined by pore-water and solid analysis, selective extractions, microscopy and sulfur K-edge X-ray absorption near-edge structure (XANES) spectroscopy. The negative impact of this stack on estuarine environments is a concerning prob...
Article
Full-text available
The Iberian Pyrite Belt (IPB) is rich in sulfide deposits which have been intensively exploited, generating a huge problem of contamination of the Odiel River by acid mine drainage (AMD). At its source is a clean river, but along a 7 km-long reach receives five discharges of acid mine waters: Concepción, San Platón, Esperanza, Poderosa and the Agri...
Article
Full-text available
Waters affected by acid mine drainage (AMD) can contain high concentrations of rare earth elements (REE) which have a great interest not only by its application as tracers in hydrogeochemical processes but also as a potential economic resource. The Iberian Pyrite Belt (IPB) is rich in sulfide deposits which have been exploited intensively since anc...
Article
Full-text available
Cyanide heap leach operations developed in Tharsis (SW Spain) from 1982 to 2001 left the legacy of a huge amount of cyanidation wastes deposited over a total area of 47 ha without any type of isolation. The main goals of this work are to study the release of metals and metalloids under rainfall occurrence and the potential impact on the aquatic lif...
Article
Waste derived from fertilizer production has been accumulated worldwide for decades, especially during the last century. This waste is mainly formed by phosphogypsum; a mixture of gypsum along with phosphates, fluorides, and organic matter, which are generated from phosphoric acid production. Phosphogypsum deposits are usually associated with an im...
Article
This paper investigates the mobility and fluxes of REE, Y and Sc under weathering conditions from an anomalously metal-rich phosphogypsum stack in SW Spain. The interactions of the phosphogypsum stack with rainfall and organic matter-rich solutions, simulating the weathering processes observed due to its location on salt-marshes, were simulated by...
Article
Based on a systematic literature search (Number of initial publications = 1571; Number of in-depth publications = 97), this paper reviews the different potential applications for phosphogypsum, the main unwanted by-product of the fertilizer industry, providing some insights into the new valorization routes, and critically describing the advantages...
Article
Full-text available
The Olivargas Reservoir is located in a remote and scarcely monitored area in the Odiel River Basin (Southwest Spain) and is used for domestic, agricultural and mining water supplies. In contrast with highly monitored reservoirs, this paper explores the application of the CE-QUAL-W2 model, that was designed by Cole andWells in 2005, to a poorly mon...
Article
Fluxes of acidity and contaminants from acid mine drainage (AMD) sources to the receiving surface water bodies were studied in a mining-impacted watershed (Meca River, SW Spain) using a novel methodology based on the joint application of EMMA and MIX codes. The application of EMMA and elemental ratios allowed delimiting the end-members responsible...
Article
Phosphogypsum is the main waste generated by the phosphate fertilizer industry. Despite the high level of pollutants found in phosphogypsum and the proximity of stacks to cities, there are no specific regulations for the management of this waste. This study addresses this issue by applying to phosphogypsum, from a fertilizer plant in Huelva (SW Spa...
Article
Full-text available
The Odiel River Basin (SW Spain) drains the central part of the Iberian Pyrite Belt (IPB), a world-class example of sulfide mining district and concomitantly of acid mine drainage (AMD) pollution. The severe AMD pollution and the incipient state of remediation strategies implemented in this region, coupled with the proximity of the deadline for com...
Article
This paper explores the possibility of using wastes (i.e. solid phosphogypsum (PG), process waters and edge outflows) generated by a fertilizer plant in SW Spain as a source of elements of economic interest, estimating the available metal reserves and discussing the technological and economic pros and cons of this potential source of raw materials....
Article
This study assesses the environmental impact and the potential valorization of metal-sludge waste generated by the active neutralization of extremely metal-polluted acid mine drainage (AMD). To this end, two regulated leaching tests (EN 12457-2 and 1311 USEPA TCLP), a standardized sequential extraction protocol (BCR sequential extraction) and singl...
Conference Paper
Full-text available
The Iberian Pyrite Belt (IPB) covers a vast part of the SW of Spain and Portugal. This region is rich in sulfide deposits which have been exploited intensively. As a consequence, there is a large number of sources of acid mine drainages, characterized by very extreme pH conditions and high pollution load. Waters affected by acid mine drainage (AMD)...
Article
The Odiel watershed drains materials belonging to the Iberian Pyrite Belt, where significant massive sulfide deposits have been mined historically. As a result, a huge amount of sulfide-rich wastes are deposited in the watershed, which suffer from oxidation, releasing acidic lixiviates with high sulfate and metal concentrations. In order to reliabl...
Conference Paper
Full-text available
Your abstract must use Normal style and must fit in this box. Your abstract should be no longer than 300 words. The box will 'expand' over 2 pages as you add text/diagrams into it.) Preparation of Your Abstract 1. The title should be as brief as possible but long enough to indicate clearly the nature of the study. Capitalise the first letter of the...
Article
Phosphogypsum wastes from phosphate fertilizer industries are stockpiled in stacks with high contamination potential. An assessment of the environmental impact, including the use of geochemical tracers such as rare earth elements (REE) and Cl/Br ratios, was carried out in the phosphogypsum stack located at the Estuary of Huelva (SW Spain). Inside t...
Article
Underground mine drainages are extremely difficult to study due to the lack of information about the flow path and source proximity in relation to the outflow adit. Geochemical processes controlling metals and acidity fluxes in a complex anthropogenic mine aquifer in SW Spain during the dry and rainy season were investigated by geochemical and stat...
Article
In the Iberian Pyrite Belt (IPB), especially within the Tinto and Odiel River basins, there is a large number of sources of acid mine drainages (AMD), characterised by very extreme pH conditions and pollution levels. This paper studies the main factors governing the composition of the different leachates, based on ionic relationships. Statistically...
Article
Compared with pit lakes originated by coal mining, little is known about in-lake neutralization processes in pit lakes from sulfide ore mining in hard rock substrates, which are typically very deep and acidic and receive low carbon (C) inputs and groundwater flows. Physicochemical processes in water and sediments from a pit lake (San Telmo, 130 m d...
Article
This study deals with the hydrogeochemical changes and metal(loid) attenuation processes along the extremely acidic Rio Tinto (SW Spain). The geochemistry of Tinto headwaters is determined by the variability of mining discharges due to different geological, geochemical and hydrological controls. Downstream of the mining area, a decrease in most dis...
Article
The Tinto River estuary is highly polluted with the acid lixiviates from old sulphide mines. In this work the behaviour of dissolved and particulate trace metals under strong chemical gradients during a tidal cycle is studied. The pH values range from 4.4 with low tide to 6.9 with high tide. Precipitation of Fe and Al is intense during rising tides...
Article
The Tinto and Odiel rivers in southwest Spain drain the world's largest sulfide mineral formation: the Iberian Pyrite Belt which has been worked since 2,500 BC. The Tinto and Odiel estuarine zones include both an extensive area of salt marsh and an intensively industrialized urban area. As a consequence of pyrite oxidation, the Tinto and Odiel rive...
Article
Acid mine drainage in the Iberian Pyrite Belt is probably the worst case in the world of surface water pollution associated with mining of sulphide mineral deposits. The Iberian Pyrite Belt is located in SW Iberian Peninsula, and it has been mined during the last 4,500 years. The central and eastern part of the Iberian Pyrite Belt is drained by the...
Article
The accurate estimation of metal loads transported by streams is necessary to calculate reliable mass transfers of metals between compartments, both at local and global scales. This estimation is particularly relevant in the case of the Tinto and Odiel Rivers (SW Spain) due to their significant contribution to the total metal transfer from continen...
Article
An understanding of pollutant processes in rivers under different hydrological conditions is essential to assess its long-term evolution. This is especially relevant in Mediterranean rivers during rain events, when most of the water, suspended particulate matter (SPM), and pollutants are delivered. This study investigates the hydrochemical changes...