Environmental impact of the former Pb–Zn mining and smelting in East Belgium

In the mining district of Plombières-La Calamine (East Belgium), extensive Pb–Zn mining activities resulted in an important contamination of overbank sediments along the Geul river. Moreover, a huge amount of heavy metals is stored in a dredged mine pond tailing, which is located along the river. In the dredged mine pond tailing sediments, Pb–Zn minerals control the solubility of Zn, Pb and Cd. Although Pb, Zn and Cd display a lower solubility in overbank sediments compared to the mine tailing pond sediments, elevated concentrations of Pb, Zn and Cd are still found in the porewater of the overbank sediments. The considerable ‘actual’ and ‘potential’ mobility of Zn, Pb and Cd indicates that the mine pond tailing sediments and the overbank sediments downstream from the mine pond tailing represent a considerable threat for the environment. Besides the chemical remobilisation of metals from the sediments, the erosion of overbank sediments and the reworking of riverbed sediments act as a secondary source of pollution.     

Zn, Pb, Cu and As distribution patterns in overbank and medium-order stream sediment samples: their use in exploration and environmental geochemistry

Overbank and medium-order stream sediment samples were collected in Belgium and Luxembourg from 66 sampling locations (area of about 33,000 km²) and analysed for major and trace elements among which Zn, Pb, Cu and As. At each sampling location large bulk samples were taken, namely in the lower (normally at ≥1.5 m depth, over an interval of about 20–40 cm) and upper (normally upper 5–25 cm) parts of the overbank profiles and from the stream sediments. Furthermore, at a number of these sites, a detailed geochemical analysis of vertical overbank sediment profiles (sampling intervals of 10–20 cm) was subsequently carried out to unravel element variations through time and to help in the overall evaluation. For most sampled sections evidences such as ¹⁴C-dating and the absence of anthropogenic particles point towards a pre-industrial and often pristine origin of the lower overbank sediment samples. From the latter bulk samples, mean background concentrations were deduced. They reveal the existence of significant differences between the northern and southern part of Belgium (incl. Luxembourg) which relate to the difference in geological substrate. In the north dominantly non-lithified Quaternary and Tertiary sands, marls and clays occur while in the south Palaeozoic sandstones, shales and carbonate rocks outcrop. Consequently separate mean background values were calculated for the two areas. In the southern study area, some anomalous metal concentrations have been recorded in pre-industrial sediments. They are derived from mineralised Palaeozoic rocks, a feature which could be of interest for base metal exploration. In the upper overbank and stream sediments, in general, higher heavy metal and As contents were recorded with highest values in areas with metal mining, metal melting and cokes treatment industries. By comparing the trace element concentrations of the upper overbank or stream sediment samples with the concentrations detected in the lower overbank samples at each of the sampling locations, and by evaluating the vertical distribution patterns where available, the degree of pollution of the alluvial plain and the present-day stream sediments can be assessed. From this exercise, it is clear that highest pollution occurs in the northern part of Belgium, which relates to its high population density and industrial development.     

Heavy metal contamination of a Greenland fjord system by mine wastes

Since 1973, about 500,000 tons/yr of metal-rich particulate tailings from a lead/zinc flotation mill have been discharged through a submarine outfall into a two fjord system on the west coast of Greenland. Differential solubilization of particulate metals by seawater, seasonal water mixing, and sill exchange tailings dispersal processes have resulted in high, but seasonally variable Zn, Cd, and Pb contamination of the water, and suspended particulate matter (SPM).Chemical partition of the SPM shows that most (85-99 percent) of the Pb, but relatively low proportions of Zn (14-26 percent) and Cd (10–20 percent) are weakly bound to the SPM. Such particulate metal characteristics allow the real time effects of tailings discharges and dispersal on the system to be traced even in the sediments where tailings accumulation is very slow (0.1 cm/yr).Fjord seaweeds and blue mussels also contain varying amounts of Zn, Pb, and Cd depending on the metal and their location relative to the tailings outfall and apparently responded almost instantly to the metal contamination, as did the water and SPM. High Pb concentrations in the fjord mussels most likely derive from the preferential uptake of available particulate Pb, whereas the seaweeds appear to derive most of their heavy metal concentrations from the dissolved phase. The evidence from this and other sites as well as from experimental work, indicates that any discharge of Pb-bearing particles into the marine environment either directly as mine wastes or indirectly as from natural runoff from current and former lead mining sites results in immediate lead contamination of the in situ mussel population.     

辽宁省柴河铅锌矿开采与重金属污染历史重建

通过对辽宁铁岭柴河铅锌矿及周边地区的土壤测量及柴河水库河漫滩沉积剖面的同位素测年研究,发现柴河铅锌矿开采导致的土壤重金属污染主要集中在柴河铅锌矿区周边3~5 km的范围内,土壤pH值表明土壤明显酸化。污染历史重建显示,1820年以来,随着沉积物中S含量的不断升高,其pH值累计下降2个单位;1900年以来河漫滩沉积物中的Cd、Pb、Zn累积明显;铅锌矿停止开采后,沉积剖面中Pb、Hg含量逐年降低;汇水域内的土壤酸化仍可导致土壤中累积的Cd和Zn对水库水体和库底沉积物造成二次污染,对水库鱼类的安全具有潜在风险。     

Heavy metal anomalies in the Tinto and Odiel River and estuary system,Spain

The Tinto and Odiel rivers drain 100 km from the Rio Tinto sulphide mining district, and join at a 20-km long estuary entering the Atlantic Ocean. A reconnaissance study of heavy metal anomalies in channel sand and overbank mud of the river and estuary by semi-quantitative emission dc-arc spectrographic analysis shows the following upstream to downstream ranges in ppm (μg g^?1): As 3,000 to <200, Cd 30 to <0.1, Cu 1,500 to 10, Pb 2,000 to <10, Sb 3000 to <150, and Zn 3,000 to <200. Organic-rich (1.3–2.6% total organic carbon, TOC), sandysilty overbank clay has been analyzed to represent suspended load materials. The high content of heavy metals in the overbank clay throughout the river and estuary systems indicates the importance of suspended sediment transport for dispersing heavy metals from natural erosion and anthropogenic mining activities of the sulfide deposit. The organic-poor (0.21–0.37% TOC) river bed sand has been analyzed to represent bedload transport of naturally-occurring sulfide minerals. The sand has high concentrations of metals upstream but these decrease an order of magnitude in the lower estuary. Although heavy metal contamination of estuary mouth beach sand has been diluted to background levels estuary mud exhibits increased contamination apparently related to finer grain size, higher organic carbon content, precipitation of river-borne dissolved solids, and input of anthropogenic heavy metals from industrial sources. The contaminated estuary mud disperses to the inner shelf mud belt and offshore suspended sediment, which exhibit metal anomalies from natural erosion and mining of upstream Rio Tinto sulphide lode sources (Pb, Cu, Zn) and industrial activities within the estuary (Fe, Cr, Ti). Because heavy metal contamination of Tinto-Odiel river sediment reaches or exceeds the highest levels encountered in other river sediments of Spain and Europe, a detailed analysis of metals in water and suspended sediment throughout the system, and epidemiological analysis of heavy metal effects in humans is appropriate.     

Dispersion of tailings in the Knabena—Kvina drainage basin, Norway, 1: Evaluation of overbank sediments as sampling medium for regional geochemical mapping

Molybdenum mining in the Knabena—Kvina drainage basin (1918–1973) left more than eight million tons of tailings in two small lakes in the headwater area of the Knabena river. The piles, that reach above the water surface, were freely eroded until a dam was built to reduce the dispersion in 1976. Sampling of tailings and fluvial sediments took place almost 20 years later. Sampling media were natural sediment sources, 1-cm-thick slices of overbank sediments of various depths, material from the tailings pond, sandbars, stream sediments, fjord sediments, and integrated samples of floodplain surfaces (0–25 cm). In total 734 samples were collected. Chemical analysis (ICP-AES after aqua regia or HNO₃ extraction) showed that overbank sediments at a certain depth represent the pre-industrial trace metal concentrations within the drainage basin. The tailings and recent fluvial sediments were enriched in approximately the same element suite. The highest enrichment factors were obtained for Cu (8–53) and Mo (22–57). Fluvial processes in the tailings pond have probably selectively eroded fine-grained, low-density particles. Thus, coarse chalcopyrite may have been left behind, while molybdate associated with fine-grained particles may have been selectively entrained causing dilution of Cu and enrichment of Mo in the downstream fluvial sediments. In the sandbars, the highest Cu and Mo concentrations were found in fine-grained sediments downstream of a low-gradient reach that act as a bedload trap. On the floodplains, it is seen that the first areas to be inundated in a flood situation (proximal to the river and in depressions) have the highest metal concentrations. For regional geochemical mapping it is suggested that overbank sediment profiles along river reaches with a laterally stable or slowly migrating channel, should be sampled. In such floodplains, pre-industrial overbank sediments are usually preserved at depth. In case of laterally unstable reaches upstream of the sampling point, polluted and unpolluted sediments may be interlayered or mixed. Therefore, samples should be collected from various depths or sedimentary units in such profiles. A similar sampling strategy should probably be adopted to detect vertical migration of elements especially in areas with acid rain and low bedrock buffer capacity. To obtain high contrasts between polluted and unpolluted drainage basins, the overbank sediment profiles should be within the proximal part of the floodplain.     

Heavy metal partitioning in river sediments severely polluted by acid mine drainage in the Iberian Pyrite Belt

This study provides a geochemical partitioning pattern of Fe, Mn and potentially toxic trace elements (As, Cd, Cr, Cu, Ni, Pb, Zn) in sediments historically contaminated with acid mine drainage, as determined by using a 4-step sequential extraction scheme. At the upperstream, the sediments occur as ochreous precipitates consisting of amorphous or poorly crystalline oxy-hydroxides of Fe, and locally jarosite, whereas the estuarine sediments are composed mainly of detrital quartz, illite, kaolinite, feldspars, carbonates and heavy minerals, with minor authigenic phases (gypsum, vivianite, halite, pyrite). The sediments are severely contaminated with As, Cd, Cu, Pb and Zn, especially in the vicinity of the mining pollution sources and some sites of the estuary, where the metal concentrations are several orders of magnitude above background levels. Although a significant proportion of Zn, Cd and Cu is present in a readily soluble form, the majority of heavy metals are bonded to reducible phases, suggesting that Fe oxy-hydroxides have a dominant role in the metal accumulation. In the estuary, the sediments are potentially less reactive than in the riverine environment, because relevant concentrations of heavy metals are immobilised in the crystalline structure of minerals.     

陕西潼关金矿区太峪河底泥重金属元素的含量及污染评价

通过对潼关金矿区太峪河和太峪水库底泥中重金属元素总量的调查,探讨了金矿开发活动中重金属元素对河流底泥的污染程度。研究结果表明,除As外,河流底泥中重金属元素的含量与尾矿渣中重金属元素的含量变化一致,表明其主要来源于尾矿渣,但又明显高于尾矿渣。在同一地点河流底泥中重金属元素的含量平均高出河水中的1048.61～666030.08倍,呈显著富集。以邻近地区不受工矿活动影响的河流底泥重金属元素的含量均值作为评价参比值,太峪河底泥受到了Hg、Pb、Cd、Cu、Zn元素的极度污染,单项污染超标倍数及综合污染指数法评价结果表明,Hg、Pb、Cd平均污染超标倍数达366.90、217.42和149.97,是底泥中最主要的污染元素。河流底泥重金属元素的综合污染指数高达278.97,表明河流的复合污染亦呈极度状态。太峪河底泥受重金属元素极度污染的现实提示,矿区的环境防治工作已刻不容缓。     

Environmental geochemistry of the derelict Webbs Consols mine,New South Wales,Australia

Small-scale mining and mineral processing at the Webbs Consols polymetallic PbZnAg deposit in northern New South Wales, Australia has caused a significant environmental impact on streams, soils and vegetation. Unconfined waste rock dumps and tailings dams are the source of the problems. The partly oxidised sulphidic mine wastes contain abundant sulphides (arsenopyrite, sphalerite, galena) and oxidation products (scorodite, anglesite, smectite, Fe-oxyhydroxides), and possess extreme As and Pb (wt% levels) and elevated Ag, Cd, Cu, Sb and Zn values. Contemporary sulphide oxidation, hardpan formation, crystallisation of mineral efflorescences and acid mine drainage generation occur within the waste repositories. Acid seepages (pH 1.9–6.0) from waste dumps, tailings dams and mine workings display extreme As, Pb and Zn and elevated Cd, Cu and Sb contents. Drainage from the area is by the strongly contaminated Webbs Consols Creek and although this stream joins and is diluted by the much larger Severn River, contamination of water and stream sediments in the latter is evident for 1–5 km, and 12 km respectively, downstream of the mine site. The pronounced contamination of local and regional soils and sediments, despite the relatively small scale of the former operation, is due to the high metal tenor of abandoned waste material and the scarcity of neutralising minerals. Any rehabilitation plan of the site should include the relocation of waste materials to higher ground and capping, with only partial neutralisation of the waste to pH 4–5 in order to limit potential dissolution of scorodite and mobilisation of As into seepages and stream waters.     

湘江入湖河段沉积物重金属污染及其Pb同位素地球化学示踪

湘江是我国重金属污染最严重的河流之一.本次工作利用等离子质谱(ICP-MS)和多接收同位素质谱(MC-ICP-MS)等技术,对湘江入湖河段沉积物进行了系统的重金属微量元素和Pb同位素分析.结果表明,湘江河床沉积物明显富集Bi、Sc、V、Mn、Ni、Cu、Zn、Pb、Cd、Sn、Sb等多种重金属微量元素,而湖盆沉积物重金...     

Heavy metal contamination in the Arieş river catchment, western Romania: Implications for development of the Roşia Montană gold deposit

The Abrud–Arieş river system, western Romania, is subject to ongoing mining activity associated with Cu, Pb and Zn ore extraction. The catchment contains what is believed to be Europe's largest unutilized Au deposit at Roşia Montană that is planned to be exploited by open-cast mining techniques. The magnitude and environmental significance of metal (Cd, Cu, Pb, and Zn) concentrations in surface water and river channel sediment have been investigated along a 140 km reach of the Rivers Abrud and Arieş and 9 tributaries affected by mining. The speciation of sediment-bound metals was established using a 4-stage sequential extraction procedure (SEP) that identified four chemical phases: (1) exchangeable, (2) Fe/Mn oxides, (3) organic matter/sulphides and (4) residual. Peak solute and sediment-bound metal concentrations were found to occur in the River Abrud downstream of the EM Bucium mine and in mining-affected tributaries, with up to 71% of sites containing sediment metal concentrations in excess of Dutch intervention values. The River Arieş was found to be much less polluted than the River Abrud, with only Cu showing concentrations above guideline values, as a consequence of porphyry Cu mineralization in the catchment. The magnitude and spatial extent of metal pollution is influenced by local physico-chemical conditions and hydrological linkages between mining and local river systems. Sediment-bound Cd and Zn were found to be predominantly associated with the exchangeable phase of the sediment (9–74% and 6–65%, respectively), whilst Fe/Mn oxides (5–76%) and organic matter/sulphides (1–45%) generally accounted for a majority of Pb and Cu partitioning, respectively. Sites of environmentally significant sediment-metal pollution were identified in the Rivers Abrud and Arieş where exchangeable metal concentrations exceeded Dutch intervention values. The implications of metal contamination in the Arieş river basin to the proposed mining development at Roşia Montana are discussed in relation to other contaminated Romanian catchments and with the EU Water Framework Directive.     

High-resolution profiles of trace metals assessed by DGT techniques in lake sediment porewaters

The technique of diffusive gradients in thin films (DGT) was applied to obtain high-resolution vertical profiles of trace metals in sediment porewater of a eutrophic lake, Lake Chaohu. All sampling sediments were under anaerobic conditions with Eh values below 0, the redox potential profile in M4 was relatively stable, and higher Eh values in M4 than that in M1 were observed due to hydrodynamic effects. Fe, Mn and As exhibited closely corresponding profiles due to the co-release of Fe and Mn oxides and the reduction of As. Higher Fe and Mn concentrations and lower As concentrations were observed in M1 of the western half-lake than those in M4 of the eastern half-lake due to different sources and metal contamination levels in the two regions. Cu and Zn showed increasing concentrations similar to Mn and Fe at 1–2 cm depth of sediments, while DGT measured Co, Ni, Cd and Pb concentrations decreased down to 3–4 cm in the profiles. Co, Ni, Cu, Zn, Cd and Pb showed insignificant regional concentration variances in the western and eastern half-lakes. According to the R(C _DGT/C _{centrifugation}) values, the rank order of metal labilities decrease as follows: Fe (>1) > Cu, Pb, Zn (>0.9) > Co, Ni, Cd (>0.3) > Mn, As (>0.1).     

铅锌矿山开发导致的重金属在环境介质中的积累

以连续提取法和相关性分析研究了土法冶炼锌、铅锌和矿山开采导致的重金属在废渣及环境介质土壤、溪流沉积物中的积累，并分析了其环境危害性。结果显示，贵州赫章土法炼锌导致的重金属Pb、Zn、Cd在环境介质中的积累相当高。水城杉树林铅锌矿山开采引起的重金属积累则相对较低，但也明显高于背景值；土壤和沉积物中的铁矿物对重金属有强烈的固定作用。除残渣态外，Pb、Zn在土壤、炼锌废渣中主要呈铁锰氧化物结合态，沉积物中则为碳酸盐结合态。可交换态Pb、Zn含量变异较大，但在炼锌废渣、土壤中含量明显高于河流沉积物，暗示铅锌矿开发对土壤环境的潜在危害更大。     

Mobility of heavy metals as a function of pH of samples from an overbank sediment profile contaminated by mining activities

Parts of the flood plains north of the Harz Mountains are contaminated with heavy metals, such as Pb, Cu, Zn and Cd derived from mining, which has been carried out in the Harz Mts. since the Middle Ages. It is important to know the mobility of the heavy metals in these overbank sediments in order to estimate the danger to the environment arising from this source. This paper deals with the effect of pH on heavy-metal mobility, using a constant-pH method. The investigations were carried out on an overbank sediment profile near Salzgitter Bad, north of the Harz Mts. The mobility of the heavy metals in the overbank sediment profile is described as a function of pH and depth. Besides the mobile heavy-metal fraction at a certain pH, the buffering capacity of the sediment at this pH must be taken into consideration. The different layers of the overbank sediment profile show distinct differences in buffering capacity and a natural pH harrier could be identified in the upper part of the profile. Therefore, to avoid increasing heavy-metal mobility the natural layering of the overbank sediment profile should not be disturbed. Two different kinds of desorption experiments at constant pH are also discussed, as well as the conversion of the heavy-metal species in the ore minerals into the species in the sediment.     

小秦岭太峪水系沉积物重金属污染生态危害评价

以金矿开发影响的黄河二级支流太峪水系沉积物为研究对象,沿河采集16个表层沉积物样品,分层采集垂向剖面10件水库沉积物样品,测定了样品中重金属元素Hg、Pb、Cd、Cr、As、Cu和Zn的含量,采用Hakanson潜在生态指数法和Tomlinson污染负荷指数法评价重金属元素污染程度和潜在生态风险。结果表明,矿业活动是太峪水系沉积物重金属元素污染的主要因素;变异系数、富集系数和最高污染系数均反映Hg、Pb、Cd是太峪水系沉积物的特征污染重金属元素,Cr和As的质量分数接近地区背景值;太峪水系表层沉积物受到重金属元素的极强污染,山区段污染较山外更严重;整个流域的Hg、Pb、Cd具有很强的潜在生态危害,Cr、As、Zn的潜在生态危害轻微;太峪水系沉积物垂向各层沉积物都受到重金属元素的极强污染,生态问题以Hg、Pb、Cd的潜在生态危害为主,其污染和生态危害程度都高于流向上的沉积物。潜在生态危害指数评价突出了不同元素的毒性和危害程度,而污染负荷指数法侧重于样本空间上的污染程度,二者互补使用有利于实际问题的全面评价。     

Microbial effects on geochemical behavior of arsenic in As-contaminated sediments

The purpose of this study is to investigate the contamination level and chemical speciation of As in sediments from the Hwachon Au mine area, and to study the effects of indigenous bacteria on geochemical behavior of As in As-contaminated sediments from the mine. Concentrations of heavy metal and metalloids in one composite sample of 9 Hwachon sediments were 24.9 As mg/kg, 16.6 Cd mg/kg, 230 Pb mg/kg and 1080 Zn mg/kg. This indicates that this area was seriously contaminated with As, Cd and Zn. From the result of sequential extraction analysis, most of As (87.9%) existed as a phase of As which coprecipitated with Fe oxyhydroxides. Under aerobic condition, As concentration leached from sediments were 4 times higher in non-sterile than in sterile condition. This enrichment of As leaching could be caused by increase of pH and exudation secreted during microbial metabolism. On the other hand, under anaerobic condition, As concentration has dramatically increased in non-sterile solution with time. This As leaching has begun on 4–5th days of incubation and the highest concentration of 511 As μg/l was recorded on about 11th day. Arsenic leaching under anaerobic condition was caused by microbial enhancement of Fe leaching. Total Fe concentration increased from the 4th day, and this Fe leaching might cause lixiviation of As which had been coprecipitated with Fe oxyhydroxide.     

武汉市墨水湖沉积物重金属污染特征与防治对策

武汉市墨水湖重金属污染严重,其污染特征在我国城市湖泊中具代表性。在对墨水湖不同湖区沉积物中重金属污染物空间分布特征进行分析的基础上,应用地积累指数法探讨不同重金属元素含量随深度变化的规律和原因,并对墨水湖沉积物中重金属的污染程度进行评价表明:墨水湖沉积物中重金属元素锌和汞污染最为严重,污染程度由高到低依次为:Zn>Hg>Cu>C r>Pb>A s;从整个湖区来看,分布有排污口的周边湖区污染严重,湖心污染程度较低;沉积物中主要重金属元素含量随深度增加而降低,其变化规律主要受污染状况的影响,沉积物颗粒粒径的变化和早期成岩作用的影响不大。为了改善墨水湖水质条件和重金属污染严重的现状,必须在截污、疏浚和引水工程等基本治理措施保护下,重建和恢复沉水植物系统,才能从根本上改善湖泊水质。     

滇西沘江流域水体中重金属元素的地球化学特征

通过测定流经兰坪金顸铅锌矿区的沘江水体中Pb、Zn、Cd、As的含量和底泥中重金属元素的化学形态的含量,分析了重金属元素的分布和化学形态的变化。结果表明,沘江水遭到了Cd污染,底泥已经成为重金属元素的蓄积库,以国家土壤环境质量标准（Ⅲ级）衡量,Pb、Zn、Cd和舡分别超标3．4倍、15．8倍、106倍和2．6倍。沘江水中重金属元素含量的峰值在矿山附近的下游,而底泥中重金属元素的峰值在矿山下游30-50km的地方,矿业活动、水流变缓、pH等水体环境条件的变化都能影响水和底泥中重金属元素的含量。底泥中的Pb以碳酸盐结合态为主,Zn和Cd以铁锰氧化物结合态为主,而As以残渣态为主。Pb、Cd、Zn三种元素的环境有效态含量比较高,对沘江流域生态环境具有潜在的巨大的危害。     

Anthropogenic metal loads and their sources in stream sediments of the Me?a River catchment area (NE Slovenia)

The Me?a River Valley has been a center of mining, ore processing and iron- and steel-based metallurgical industry for more than 300 a. This paper deals with stream sediments draining this area. Loads of potentially toxic metals and metal-bearing phases were investigated 10 a after the cessation of Pb and Zn mining. Sediments in the upper Me?a River Valley show significant pollution with Pb and Zn as a consequence of mining and ore processing. The highest contents of Pb and Zn were found in the Me?a tributaries, which directly drain mine waste deposits (maximum values: 19,300 mg/kg Pb and 37,900 mg/kg Zn). These results reflect transport of contaminated material from mine waste sites and indicate that the inactive mine and its mine wastes are sources of metal contamination in the surrounding environment. Contents of Cr, Ni, Cu and Co are increased in the lower Me?a River Valley, in the area of Ravne, as a result of the iron and steel industry. The contribution of the Me?a River to the metal-load in the Drava River is evident.Metal-bearing phases, identified in stream sediments by SEM/EDS, are assigned to three areas, according to their source and genesis. The Me?ica mining district source area is characterized by ore minerals of geogenic/technogenic origin (cerussite, sphalerite, smithsonite and galena), the Ravne source area is characterized by technogenic trace metal-bearing Fe-alloys, Fe-oxides and spherical trace metal-oxides and the Me?a and Drava River catchment areas are represented by geogenic metal-bearing accessory and common rock-forming minerals, such as zircon, ilmenite, rutile, sphene, barite and monazite. SEM/EDS analyses of stream sediments agree well with the results of chemical analyses and they prove to be a very useful tool for identification of metal-bearing phases and their characterization according to source and genesis.     

内蒙古某矿矿井水重金属污染特征及来源分析

确定矿井水中重金属污染程度及主要来源,对矿井水的再利用及矿区生态环境保护具有重要的理论意义。以内蒙古某矿区为研究对象,采集地表水、第四系潜水、承压水及矿井水水样49组,检测水体中Zn、Pb、Fe、Mn、As、Cu、Cd、Cr、Hg、Se 10种重金属浓度,分析矿井水中重金属污染特征及超标情况,利用HPI模型定量评价重金属污染程度,并综合数理统计、不同类型水样重金属浓度箱形图及煤/顶板重金属浸出试验,分析矿井水重金属主要来源。结果表明:内蒙古某矿矿井水中Zn、Pb、Fe、Mn、As 5种重金属浓度值超标,其中Fe和Zn的超标率高达100%;7个矿井水样中6个矿井水的HPI值大于临界值100,矿井水重金属污染程度较高;矿井水中的Pb、As主要来源于采煤及运输机械油类物质泄漏,Mn主要来源于Ⅲ含地下水,Fe、Zn主要来源于Ⅲ含地下水及煤层中含Fe、Zn矿物的溶滤。该结论将为矿井水中重金属污染防治提供基础与依据。