Environmental impact of toxic metals and metalloids from the Muñón Cimero mercury-mining area (Asturias, Spain).
This paper presents the results of the sampling surveys carried out in order to evaluate the environmental problems associated to La Soterraña, an abandoned Hg mine in Asturias, north of Spain. In particular, this paper overviews the impact of mining and metallurgical activities on terrestrial and aquatic environments. The wastes generated during the mining activity (ore extraction and processing) and later accumulated on the ground, contain great amount of sulphides, becoming potentially acid-generating. Consequently, the mobility of heavy metals and other ecotoxic elements is enhanced. Wastes are generally located close to watercourses and on very steep hillsides, where they are exposed to oxidative weathering, posing a significant risk due to the release of ecotoxic elements to the environment. Background levels were determined at sites, which had not been directly affected by mercury mining. A multielemental geochemical study of mining wastes, soils, stream sediments, water and air samples collected in the area of influence of the old mining and metallurgical works was carried out. Total Hg and As concentrations in soils reach values up to 502 and 19,940 mg kg(-1), respectively, 500 and 2000 times higher than the local background levels. The effects of mining seem to be intense both in waters and stream sediments, as well as in the local atmosphere, whose Hg content is 10 times higher than the background level in the area. Therefore, the target carcinogenic risk was exceeded for As and Hg in La Soterraña site.
Loredo
Jorge
J
Departamento de Explotación y Prospección de Minas, E.T.S. Ingenieros de Minas. University of Oviedo, c/Independencia 13, 33004 Oviedo, Asturias, Spain.
Ordóñez
Almudena
A
Alvarez
Rodrigo
R
D000395:Air Pollutants, Occupational / Q000032:analysis; D004785:Environmental Pollutants / Q000009:adverse effects* / Q000032:analysis; D004787:Environmental Pollution / Q000009:adverse effects* / Q000032:analysis; D055593:Geological Phenomena; D005844:Geology; D006801:Humans; D007220:Industrial Waste / Q000009:adverse effects / Q000032:analysis; D008628:Mercury / Q000032:analysis*; D008670:Metals / Q000009:adverse effects* / Q000032:analysis; D008906:Mining; D009942:Organometallic Compounds / Q000009:adverse effects* / Q000032:analysis; D018570:Risk Assessment; D012989:Soil Pollutants / Q000032:analysis; D014874:Water Pollutants, Chemical / Q000032:analysis; D014881:Water Supply
D000395:Air Pollutants, Occupational; D004785:Environmental Pollutants; D007220:Industrial Waste; D008670:Metals; D009942:Organometallic Compounds; D012989:Soil Pollutants; D014874:Water Pollutants, Chemical; D008628:Mercury