IMPACT OF MINING SOLID WASTE IN ALBANIA AND RECOMMENDATION TO DECREASE POLLUTION IN SURROUNDING AREAS. 1

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1 IMPACT OF MINING SOLID WASTE IN ALBANIA AND RECOMMENDATION TO DECREASE POLLUTION IN SURROUNDING AREAS. 1 Demi Genc 2, Goskolli Edmond, Shushku Bardh 3 and Girolamo Belardi Abstract: The activity of mines has left big quantities of solid waste distributed all over the territory of Albania, but mainly close to the mines and mineral processing plants. The main stock piles and tailings dams of mining solid waste of Albania are located close to the rivers that are flowing to Adriatic Sea. However main mines and mineral processing plants are not in operation, the impact of their solid waste deposited for a long time continue to be some times visible and mostly harmful for human beings, animals and plants in surrounding environment. The most imperative damages are from solid wastes of copper mines. The water, sediments and land surround these objects content heavy metals, usually copper, zinc and nickel over permitted levels. It was determined the location in the map of Albania and was measured the quantity of these solid wastes for every mine, as well as was analysed their chemical composition. The effect of solid wastes in the environment depends on the location where they are deposited, and their chemical composition. As a consequence of reaction of composed minerals in mining solid waste the water is polluted especially that is close to copper mining waste stock piles. A study was carried out in order to analyse the ways for remediation and rehabilitation of mining solid waste aiming to decrease the pollution under the levels determined by the EC norms. Coal mining waste In Albania, many different mines were used for extraction and enrichment of coal. However, today most of them are closed, with certain minor exceptions. During the mines lifetimes, coal enrichment and its usage have produced approximately 14.5 million ton of solid wastes, which are deposited around the mines where they came from. (Goskollı E.) These wastes have about 3% coal, 2% sulphur, and 95% clays, mergele and alevrolite. The latter do not expose any environmental risks, and can be used as a primary component for building bricks. Over these solid wastes there is almost normal vegetation. (Demi 2000) 1 Paper was presented at Mining and the Environment Conference, Sudbury, Ontario, Canada October 19-27, Demi Genc, Assistant Professor of Mineral Processing, National Agency of Natural Resources (AKBN), Director of Mineral Promotion, Tirana, Albania, DEMISDEA@albmail.com Goskolli Edmond, Assistant Professor of Mining, National Agency of Natural Resources (AKBN), Director of Mining Department, Tirana, Albania 3 Shushku Bardh, Mining Engineer, National Agency of Natural Resources (AKBN), expert in Mining Monitoring Directory, Tirana, Albania

2 The solid wastes have formed small hill-like structures, which are un-systematically distributed around the mines. Very rarely, some of the solid wastes are self-burnt, and upon heat they release a smelly smoke. Creeks that run through solid coal wastes are not drinkable, but they have resulted to be useful in watering agricultural vegetation. In the Albanian map are determined the locations of the largest solid waste congregations. Forestation of mineral solid wastes and coal factories is strongly recommended. Chromium mining waste Chromium is one of the most important minerals in Albania. In addition, Albania is the third-richest country with chromium in the world; because of this, chromium reserves have been used with high intensity. As a result, considerable large amounts of solid wastes have been formed. During 2004, all solid chromium wastes near their respective mines were inspected to determine exact location, quantities, and chemical composition of wastes. From this monitoring procedure, it resulted that there are 18 million ton of solid chromium wastes that are located around their respective mines. From mineralogical analysis done with samples taken from these wastes, it resulted that they are made up of 3-4% of olivine, rhombus pyroxene and chromium minerals. Therefore, they are not environmentally dangerous. Nevertheless, natural vegetation above them is not possible. Their surface layers are affected from atmospheric agents, which continuously change and serpentinize the solids and form iron hydroxide surfaces.(goskollı E.) Table 1: Chromium mines in Katjel Surface ground Compounds Layer (mg/kg) Leaching tests of solid wastes with acetic acid (mg/l) Leaching tests of solid wastes analytical, (%) Chromium (VI) <4 Arsenic 5 <0.01 Cadmium 2 <0.005 Copper 16 < Chromium Iron Lead 7 < Mercury <1 <0.005 Nickel Zinc Cobalt Manganese Magnesium 0.92 P2O K2O Na ph 9.9

3 The analysis of the running waters that go through the solid wastes show that they do not contain any harmful or dangerous compounds. They are actually used for drinking and for watering plants. The Chromium Processing Factory in Bulqiza works by recycling solid wastes that have been deposited near it during its 25-year long activity. There are around 2.5 million ton solid wastes near it, which are composed of Cr2O3 (about 13%). After the recycling process of the wastes, the chromium concentrate became 44% of Cr2O3. (Demı G.) Surface samples from the ground and from solid chromium wastes were taken from one of the mines in Katjel. The results of the analysis of both samples are shown in the table below (Myftıu G.): As shown in Table 1, the total concentrations of nickel and chromium of the ground surface are relatively considerable. Leaching tests with acetic acid done on samples of the sterile rock show a considerable leaching of chromium and nickel. Ferro-Nickel mining waste Before the 1990 s, many mines were used for processing of Ferro-nickel materials. These mines have completely stopped their activities since then. From monitoring these sites, it is shown that there is about 4 million ton solid wastes near these exmines. The solid wastes are located around the mines, in an un-systematically pattern.( Goskollı E.) Mineralized objects of ore are positioned in between ultra-basic rocks and carbonic deposits of Upper Kreta. As a result, sterile wastes are made up of ultra-basic and lime rocks. They also have small amounts of ferro-nickel minerals. Samples of solid waste stocks were taken for analysis from the Ferro-Nickel Mine in Prrenjas. The results of the analysis are shown in the table below (Myftıu G.): Table 2: Ferro-Nickel Mine in Prrenjas Compounds Leaching tests of sterile wastes with acetic acid, Leaching tests of ore wastes with acetic acid, Tests of sterile wastes, analytical % (mg/l) (mg/l) Arsenic <0.01 <0.01 Cadmium <0.005 <0.005 Cooper <0.01 < Chromium <0.02 < Iron <0.1 < Lead <0.05 < Mercury <0.005 <0.005 Nickel Zinc < Cobalt Manganese Magnesium 0.90 P2O K2O Na ph 8.3

4 Sterile waste stocks can become dangerous to the health and security of the local communities. Some dangers include the breakdown of sterile-waste dams, erosions landslides, and contaminated running waters in the surrounding environment. The leaching tests which were done on the taken samples show a considerable leaching potential for nickel, chromium, zinc. A number of projects will be undertaken in order to minimize the erosion of stocks without vegetation, to minimize the negative impact of the surrounding view of the environment, and to minimize the effects that sterile stocks may have on health and security of local communities. Copper mining waste Copper mining solid waste are more aggressive than those from other mines, because they contain sulphur minerals. Stream and rain waters that run through such sterile contain SO4 - ions, therefore they are acidic and harmful to the environment where they pass and are transferred. Additionally, they contain heavy metals such as copper and zinc. More often than not, these heavy metals are in larger amounts than permitted. Atmospheric agents affect these large quantities of sterile. These distributions enlarge the dangerous potential sterile have on the surrounding environments and on living organisms around the effected area. In 1989, there were 20 copper mines working, 6 copper mineral processing plants, 2 copper melting factories, and 1 refinery and wire/cable factory. Currently, there is only one working copper mine and one copper-zinc mineral processing plant.(sweco Company). As a result of this activity, considerably large amounts of solid sterile have been accumulated from copper mineral processing plants. By monitoring during 2004, it resulted that the total amount of copper sterile accumulated from mines is 19 million ton, and from mineral processing plants 6.4 million ton. Analyses were done to identify various effects that sterile copper wastes might have on soil. It was shown that the sterile near mines and factories have a high potential to change the quality of soil due to the high concentration of heavy metals such as copper and zinc. It was also shown that they affect the quality of running surface streams that pass near them.(goskollı E.) This project was done from April 1998 until end of In the project was made possible by the work of the personnel of the Mining and Processing Technology Institute of Tirana in collaboration with SWECO, a Swedish company with large experience in this field. The object of monitoring was to determine the actual debris accumulated in the environment. During monitoring, none of the mines and factories were working, excluding the time between April 98 until April 99 when the mine and factory s yield was low. The monitoring activity includes: Water samples in rivers and in waste waters from mines, mineral processing plants and metallurgy in Rubik; Approximate measurements of incoming water where samples were taken; Sediment samples in interesting sites in river beds; Analyses of water samples. Measurements of incoming waters are made in samples sites, also. Samples were analyzed primarily for ph, conductivity, alkalinity, metals and in some occasions for nutrients. After the first monitoring rounds, it was recommended that the analyses of Cu, Zn, and ph were enough. Additionally, it was recommended the observation of dams and measurements of incoming water quantities. Samples were analyzed for ph, conductivity, and for concentration of copper and zinc metals during Some of the results show very high concentrations: Cu > 45 µg/l and Zn> 300 µg/l. In

5 some other cases the Swedish Agency considers the levels to be high and harmful for the protection of the environment Cu 9-45µg/l and Zn µg/l. Based on these analyses, it was possible to calculate the total amounts of copper and zinc that has come out from mines discharge, as well as the quantity that is transported through streams and rivers in the Adriatic Sea. These results are shown below (Sweco Company): Table 3: Mines discharge Copper (ton/year) Zinc (ton/year) Mines Qaf Lak Spaci, Total Sta :2* -- April January April Sept April Sept May October April January April Sept The concentration of copper and zinc in the river systems shows a continuous decrease from the first monitoring until the end of This decrease occurs due to the closing of all activities in mines and mineral processing plants in June Nevertheless, in 2003 there is an increase in concentration. This increase is thought to have occurred due to rainfalls, which have been much more this year than in former years and the sampling time has been just after heavy rainfalls. Heavy rainfalls might be abrasive to dams, producing considerable amounts of sterile that were transported into the rivers. The increase might also be due to the filter layer of soil, which is between the dams and the river, becoming saturated.(goskollı E.) Increasing quantities of metals shown in sample #28, demonstrate that large deposits of metal sediments have accrued in the lower part of the river system. Metal transportation also might increase significantly due to the large incoming water flow during heavy rainfalls. Solid wastes and the analyses of leaching processes were focused in the stocks of mines sterile, in mineral processing plants dams, and in the deposits of solid wastes in metallurgy and refinery. The laboratorial analyses confirmed that the melting factory in Rubik was highly contaminated with copper and other metals such as lead, chromium, zinc, and arsenic. The concentration of copper around the production site was above 10,000 mg/kg in each soil sample. It was also very high around the entire factory s site. Copper concentration in Repsi Factory was between 280mg/kg and 3700mg/kg. In comparison, the international levels for copper concentrations in industrial sites are between mg/kg.(Sweco) Metal concentration was relatively lower in the higher portions of dams. This shows that atmospheric agents have washed out heavy metals from dams surfaces, and have forced their solutions into the river s directions.

6 Recommendations for regulation. Mineral Processing Plants The main environmental risks from the three mineral processing PLANTS in Reps, Fush-Arrez, and Rreshen, are dependent of their dams sterile. If the factories are not working, their surroundings become polluted, but without affecting the environment in a large degree. The locations of these factories, away from river systems, give a chance to natural processes to degrade and neutralize acidic solutions that come from factories. Repsi s factory is the most environmentally dangerous one due to its size and due to the locations of its dams in relation to the river system. A long term protection of the environment can be secured if dams would be covered up. This will slow down oxidation and will minimize leaching processes. The only method that could be used for most of the dams is to conceal them. The covering material should be dense and have high water capacity in order to prevent diffusion of oxygen. The material could be natural, such as clays, clay sediment, turbe (gravel) or agricultural soil. In addition, it is important to secure dams in case of natural disasters, like major flooding, gusty winds, etc. The recommendations to regulate dams are focused mostly in their stabilization, minimization of underground running waters, and prevention of soil erosions. (Goskollı E.) The surfaces around purification factories should be cleaned up by taking away ore leftovers and concentrates, and accruing all wastes in one site, that is compliant to the surroundings. Finally, concealment of dams will minimize exposure to erosion and atmospheric factors. Melting factory in Rubik Studies show that the location is extremely polluted. Regulation of the environment should be focused into preventing contact of people with the polluted materials, and also in preventing further contamination of the soil. When the factory closes, the surroundings should be cleaned up, by moving most of the soil around the producing zone. A larger stock should be built to include all concentrates and wastes that have accrued, in a specified zone that will be safe. The polluted material should be stocked into a safe zone with other stock wastes, which has been especially projected. Shortly, this technique is objected to create a water impenetrable layer, an interrupting pond that will accumulate eventual running waters in the peripheries, and a fixed waterair layer over the waste stock. Incoming underground water flow and hill-running waters should be stopped from going through this zone. (Sweco Company) Conclusions and recommendations Based on past monitoring, it results that pollution comes from mines and copper processing factories wastes. This pollution is above the permitted levels and is dangerous to the surrounding environment, the monitored sites that are adjacent to the Adriatic Sea and for all living organisms around the area. From the results, considerable quantities of heavy metals are continuously being dumped in the Adriatic Sea every year. It is recommended to decrease pollution and bring it to at least the permitted levels, so that: Monitoring of pollution that comes from mines and copper processing factories continues. Projects for regulation and rehabilitation of stocks of mines and processing factories are undertaken.

7 References Demi G., Boci S., 2000 Study: Inventory of solid waste in mines and dressing plants of Albania, p Goskolli E., Demi G., Shushku B., 2004 Project: Mineral Processing plants dams and main stock piles of the mines, p Sweco Company&MPTI, 1999 The Project: Fani River Environmental Rehabilitation Programme. Myftıu G., D Appolonıa Comapany, Update of Natıonal Envıronmental Actıon Plan, Immedıate Measures