Distribution and Identification of Sources of Heavy Metals in the Voghji River Basin Impacted by Mining Activities (Armenia)
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Hindawi Journal of Chemistry Volume 2018, Article ID 7172426, 9 pages https://doi.org/10.1155/2018/7172426 Research Article Distribution and Identification of Sources of Heavy Metals in the Voghji River Basin Impacted by Mining Activities (Armenia) A. V. Gabrielyan,1 G. A. Shahnazaryan ,1 andS.H.Minasyan2 1 “Environmental Monitoring and Information Center” SNCO, 0012 Yerevan, Armenia 2InstituteofChemicalPhysics,NASRA,0014Yerevan,Armenia Correspondence should be addressed to G. A. Shahnazaryan; gayane [email protected] Received 23 December 2017; Revised 11 February 2018; Accepted 18 February 2018; Published 18 March 2018 Academic Editor: Xiao-San Luo Copyright © 2018 A. V.Gabrielyan et al. Tis is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. Te objective of this research is to assess the distribution of heavy metals in the waters and sediments of the Voghji River and its tributaries impacted by mining activity and to reveal the real source of each of the heavy metals in the environment for assessing the pollution level of heavy metals. Voghji River with two main tributaries (Geghi and Norashenik) drain two mining regions. To identify distribution and pollution sources of heavy metals, the water and sediment samples were collected from eight sampling sites. Te results of statistical analysis based on data sets of the period 2014–2016 showed that, afer the infuence of drainage water and wastewater of mining regions, heavy metal contents in the Voghji River basin dramatically increased. Te waters of the Voghji River were highly polluted by Mn, Co, Cu, Zn, Mo, Cd, and Pb. Te relation of metals content was highly changed due to anthropogenic impact disturbing the geochemical balance of the Voghji River. Te water quality based on only heavy metal contents in the source of the Voghji River belongs to “good” chemical status, and in the sources of Geghi and Norashenik Rivers it is “moderate.” Te water quality of Voghji and Norashenik Rivers is sharply worsening afer the infuence of mining activity, becoming “bad” chemical status. Te research revealed the pollution sources of each metal. 1. Introduction streams transport high contents of toxic trace elements such asAs,Cd,Pb,Zn,Cu,Sb,andSe[9]. Impactofminingonaquaticecosystemsbecameanissueof Heavy metals are an important class of pollutants which increasing concern. Mining by its nature consumes, diverts, can produce considerable harm to the environment when and seriously pollutes water resources [1–3]. Mining and they are above certain concentrations [10–12]. Tese elements milling operations, together with grinding, concentrating canbeleachedintothesurfacewaterorgroundwater,taken ores, and disposal of tailings, provide obvious sources of up by plants, and can bond semipermanently with soil contamination in the surface environment, along with dis- components such as clay or organic matter, which later afect charge or overfow of wastewater, runof from rainfall or human health [13]. Afer heavy metals enter into a water snowmelt, drainage from the toe of waste piles, and discharge body, they can harm aquatic organisms, and, through the of impacted groundwater to streams and springs. Water processes of chemical adsorption and physical precipitation, pollution problems caused by mining include acid mine heavy metals can accumulate in the sediments of the water drainage, metal contamination, and increased sediment levels environment [14]. Heavy metal contents of the surface sedi- in streams [4, 5]. Te generation of acidic drainage and ments are generally signifcantly higher compared with those the release of water containing high concentrations of dis- in the water body, so it is very important to explore the heavy solved metals from mine wastes constitute an environmental metalcontentsinthesurfacesediments[15,16]. problem of international scale [6–8]. Chemical leaching of Heavy metals are defned as metallic elements that have a metals occurs when precipitation from rainfall or snowmelt relatively high density compared to water. With the assump- infltrates through ore or waste materials and dissolves or tion that heaviness and toxicity are interrelated, heavy metals desorbs metals from the solid material. As a consequence, alsoincludemetalloids,suchasarsenic,thatareabletoinduce 2 Journal of Chemistry Table 1: Summary of sampling sites (water and sediment) of the Voghji River basin. Site River Location description 1 Voghji Upstream of the Kajaran city before confuence with ZCMC 2 Voghji Downstream of the Kajaran city, afer confuence with ZCMC 3 Voghji Upstream of the Kapan city, afer runof Geghi River 4 Voghji Downstream of the Kapan city, afer runof wastewaters of KPM, Kavart, and Geghanush 5 Norashenik Before confuence wastewater of tailings dam of Artshvanik 6Norashenik Mouth 7 Geghi Source 8 Geghi Mouth toxicity at a low level of exposure and nonmetal selenium River in the territory of the Kajaran city, in the southeast of [17]. Armenia. ZCMC is the largest in the region open pit mine Te mining industry is developed in the Republic of which extracts copper and molybdenum-rich ore, aferwards Armenia (RA). Due to the lack of adequate management and producing two separate concentrates of copper and molybde- planning, as well as poor operating experience and waste num. ZCMC produces 21 Mt of ore (and the similar amount management, this branch of industry is one of the main of waste) annually. Besides the basic elements, a number of sources of water pollution and of the environment, in general, valuable associated elements exist in the ore, such as Pb, Zn, with heavy metals (Pb, Cu, Ni, Cd, Mo, As, etc.). Previous Cd, As, Co, and Ni. Te slurry tailings, 33% of which is water, studies in the Voghji River basin [18–21] have all found are transported from the plant of ZCMC to the tailings dam elevated concentrations of heavy metals and trace elements of Artsvanik by pipeline. Te tailings dam of Artsvanik is suchasAs,Cu,Mo,Sb,Cu,Co,Ni,andZninthesurface located in the gorge of the same river. Afer precipitation of waters and sediments. Te pollution problems were reported slurry tailings, the surface water of tailings dam fows into in soils located near kindergarten and schools of the Kapan the Norashenik River. Besides, drainage waters (surface and and Kajaran cities [22, 23]. ground) from open pit mine also fow into the Voghji River However, inadequate information is available on the in the territory of Kajaran city. concentrations and distribution of heavy metals and trace Te second mining district (Kapan Polymetal) is located elements in the Voghji River basin. Te aim of this study inthedownstreamoftheVoghjiRiver,1.5kmeastofthe was therefore to investigate the distribution of heavy metals town of Kapan in the southeast of Armenia. Kapan Polymetal (Ti,Fe,Mn,V,Cr,Co,Ni,Cu,Zn,As,Se,Mo,Cd,Sb, (KPM) is fully mechanized underground mine with a current Pb) in the waters and sediments of the Voghji River and its capacity of approximately 400 ktpa, a conventional 750 ktpa tributaries impacted by mining activity; to reveal the source fotation concentrator, and various infrastructure facilities. of each of heavy metals in the environment and correlation Te mine produces gold-copper-silver and zinc concentrate. between parameters, to assess the pollution level of heavy Tailings of KPM are discharged into the tailings dam of metals; and to estimate the temporal variability infuence in Geghanush located in the gorge of the same river. Afer concentrations of heavy metals. precipitation of slurry tailings in the tailings dam, the tailing liquid fows into the Geghanush River and then Voghji River. Near the city of Kapan, the abandoned mine of Kavart (not 2. Materials and Methods belonging to KPM) is located which is considered a possible source of metal’s pollution. Te waters of Kavart rich in heavy 2.1. Study Area. Voghji River is a lef tributary of Aras metalsmixwithsurfaceandgroundwatersindiferentways. River located in the southeast of Armenia. Te sources of Voghji River are mountain springs and small lakes of the Kaputjugh Mountain at an elevation of 3650 m above sea 2.2. Sample Collection and Analysis. Water and sediment level located in the west-southern part of Armenia. Te total samples were collected at 8 sampling sites of the Voghji River basin in the period 2014–2016 (see Figure 1, Table 1). length of the River is 82 km (in Armenia 52 km) and the 2 2 Te sampling sites were selected with the aim of covering catchment basin area is 2337 km (in Armenia 1240.47 km ). the whole stream from its source to its confuence with two Te largest tributaries are Geghi and Norashenik. On its way, mining areas. Te sampling sites were categorized in two the stream is fed by groundwater, rain, and melting snow and groups: sampling sites 1, 5, and 7 are located in the source has perennial fow throughout the year. Mean annual water of rivers, which have the minimal anthropogenic infuence discharges of the Voghji, Norashenik, and Geghi Rivers are 3 representing the background state of the river basin; sampling estimated to be 334.3, 69.7, and 135.3 million m or 10.6, 2.21, 3 sites 2, 4, and 6 bear the infuence of mining activity and and 4.29 m /s, respectively [24]. untreated wastewater of the cities. Te Voghji River passes through the two mining districts. Water samples were collected on a monthly basis. Te One of them is Zangezur copper-molybdenum combine frequencyofsamplinginthesourcesofVoghji(WS-1),Geghi (ZCMC) which is located in the upstream of the Voghji (WS-7), and Artsvanik (WS-5) Rivers was less compared to Journal of Chemistry 3 N Sediment sampling points River water sampling points Cities Rivers Armenia state border (km) Voghji river basin 0 2 4 8 12 16 Reservoir Figure 1: Map of the study area and location of sampling points: (mining area 1) ZCMC; (mining area 2) KPM; (WS) water sampling sites; (SS) sediment sampling sites; red arrows indicate pollution sources.