並列タイトル等セルビア国東部ボール・マイデンペック鉱山地域の地下水と河川水の地球化学的・安定同位体的研究：地下水への環境負荷の意味
一般注記Contamination of water bodies is a large problem in many mining areas in the world. A similar problem exists in Eastern Serbia, where mining activities have been carried out for about 120 years. Currently, in Eastern Serbia, there are four active copper mines, three in the Bor mining area and one in the Majdanpek mining area. The long history of mining in the Bor mining area has led to serious environmental problems, which are most pronounced on water pollution downstream of the mining sites. This research aims to clarify the geochemistry of river water and groundwater in the study area and to estimate the environmental impact on groundwater in the Bor and Majdanpek mining areas.River water of Bor River, Krivelj River and Bela River located in the Bor mining area showed acidic pH ranging from 2.9 to 5.1, from upstream to downstream direction, with high concentrations of SO42-, Fe, As, Cu and Mn. River water of Small Pek River and the upper reach of Pek River are characterized by weakly alkaline pH and high concentrations of SO42-, Fe, As, Cu and Mn, although lower than the concentrations of these components in river water in the Bor mining area. The acidic river water in the Bor mining area transports large quantities of heavy metals and arsenic downstream, including 6900 t/year of Fe, 42 t/year of As, 910 t/year of Cu and 187 t/year of Mn. On the other hand, the weakly alkaline river water in the Majdanpek mining area transports smaller quantities of heavy metals and arsenic downstream (160 t/year of Fe, 0.1 t/year of As, 6 t/year of Cu and 272 t/year of Mn). This indicates that the environmental impact in the Bor mining area is significantly larger than that in the Majdanpek mining area. However, concentrations of SO42-, Fe, As, Cu and Mn in Bela River in the Bor mining area have greatly decreased after mixing of acidic polluted water of Bela River with water of Timok River containing a high bicarbonate concentration. This fact suggests that river water in the study area including Bor and Majdanpek mining areas has sufficient capacity for neutralization.Stable isotope ratios of groundwater are typical for the moderate continental climate. However, groundwater samples collected in mountainous areas are relatively depleted in δD and δ18O compared with samples that are collected in plain areas of thestudy area. This difference is thought to be caused by the altitude effect due to the Rayleigh process, which means that precipitations enriched in stable isotopes, that form groundwater in the study area, will occur first in the plain areas, and going towards higher altitudes precipitations will become depleted in stable isotopes.Groundwater in the study area is characterized by pH values ranging from 6.4 to 8.8 and a high concentration of HCO3-. The groundwater is Ca-Mg-HCO3-dominant type water. In general, groundwater from the study area has good quality with low content of trace elements, which are below maximum admissible concentrations according to the Serbian standard for drinking water. Trace elements that are mainly present in groundwater are Ba and Sr. Barium and strontium concentrations are especially high in limestone-rich areas.To determine whether mining activities are causing groundwater pollution in the study area, geochemical maps were created and threshold values for discrimination of anomalous populations from background populations were estimated for Ca2+, SO42-, and 24 other components. Geochemical maps created for Ca2+ and SO42- show that groundwater with high concentrations of these components is found along polluted rivers downstream of the Bor mining area, especially in the area along the Bela River. The actual concentrations of Ca2+ and SO42- exceeded the threshold values, although the concentrations in some groundwater samples in the area downstream of the Bor mine were below the standard values. Pollution of the groundwater along the polluted rivers is therefore thought to have been caused by mining activities of the Bor mine. Elevated concentrations of the studied components in groundwater from the Majdanpek mining area were not detected.Based on the mixing analysis between interstitial water present in tailings along strongly polluted rivers and unpolluted groundwater, it is thought that interstitial water in tailings along Bor River and Bela River is causing pollution of groundwater in the vicinity of those rivers. While river water does not directly affect groundwater in the study area.Calcium and sulfate concentrations were shown to be good indicators for monitoring of early-stage groundwater pollution caused by mining activities in thestudy area, this evaluation is mainly suitable for groundwater with a near-neutral pH. In addition to this, the evaluation method used in this study, which is based on geochemical maps, threshold values and mixing analysis considering geochemical reactions, is widely applicable to environmental assessment in mining areas.
コレクション（個別）国立国会図書館デジタルコレクション > デジタル化資料 > 博士論文
受理日（W3CDTF）2021-12-07T08:33:55+09:00
連携機関・データベース国立国会図書館 : 国立国会図書館デジタルコレクション