Environmental Impact Assessment in the Former Mining Area of Regoufe (Arouca, Portugal): Contributions to Future Remediation Measures

Nuno Durães, Luís Portela, Sara Sousa, Carla Patinha and Eduardo Ferreira da Silva
Additional contact information
Nuno Durães: GeoBioTec—Department of Geosciences, University of Aveiro, Campus de Santiago, 3810-193 Aveiro, Portugal
Luís Portela: GeoBioTec—Department of Geosciences, University of Aveiro, Campus de Santiago, 3810-193 Aveiro, Portugal
Sara Sousa: GeoBioTec—Department of Geosciences, University of Aveiro, Campus de Santiago, 3810-193 Aveiro, Portugal
Carla Patinha: GeoBioTec—Department of Geosciences, University of Aveiro, Campus de Santiago, 3810-193 Aveiro, Portugal
Eduardo Ferreira da Silva: GeoBioTec—Department of Geosciences, University of Aveiro, Campus de Santiago, 3810-193 Aveiro, Portugal

IJERPH, 2021, vol. 18, issue 3, 1-16

Abstract: The W-Sn Regoufe mine, closed since the 1970s, was once intensively exploited for tungsten concentrates. Throughout its activity, considerable amounts of arsenopyrite-rich mine wastes were produced and, to this day, are still exposed to weathering conditions. Thus, this work aims at assessing soil contamination, using a combination of chemical, physicochemical and mineralogical analyses and sequential selective chemical extraction of the main potentially toxic elements (PTEs) in topsoils. Results show that Regoufe soils are enriched in most of the PTEs associated with the ore assemblage, but As and Cd contents far outstrip both international and national guidelines. The estimated contamination factor reveals that 67% of soil samples are classified as highly to ultra-highly contaminated. Similar distribution patterns, with the main focus around the unsealed mine adits, are observed when spatially projecting the modified degree of contamination ( m C d ) and arsenic contents. Fe-oxyhydroxides and organic matter demonstrate to have a preponderant role in the retention of Cd and As. In fact, despite the high PTE contents in soils, local surface waters are characterised by low metal(loid) contents and nearly neutral pH, with PTE concentrations below national thresholds for irrigation waters.

Keywords: contamination; arsenic; cadmium; mine; soils; surface waters; PTEs; sequential selective chemical extraction; modified degree of contamination (search for similar items in EconPapers)
JEL-codes: I I1 I3 Q Q5 (search for similar items in EconPapers)
Date: 2021
References: View references in EconPapers View complete reference list from CitEc
Citations:

Downloads: (external link)
https://www.mdpi.com/1660-4601/18/3/1180/pdf (application/pdf)
https://www.mdpi.com/1660-4601/18/3/1180/ (text/html)

Related works:
This item may be available elsewhere in EconPapers: Search for items with the same title.

Export reference: BibTeX RIS (EndNote, ProCite, RefMan) HTML/Text

Persistent link: https://EconPapers.repec.org/RePEc:gam:jijerp:v:18:y:2021:i:3:p:1180-:d:489051

Access Statistics for this article

IJERPH is currently edited by Ms. Jenna Liu

More articles in IJERPH from MDPI
Bibliographic data for series maintained by MDPI Indexing Manager ().