Hydrogeological aspects of coal exploitation in Pelagonia basin (Macedonia)

Leţišta uglja „Suvodol“, „Brod-Gneotino“ su u eksploataciji, a leţište uglja „Ţivojno“ je u fazi pripremi. Nalaze se u krajnjem jugoistočnom i juţnom delu Pelagonijske kotline. Sva tri leţišta stvorena su u neogenim sedimentima u jezerskim uslovima sedimentacije u zoni kontakta sa prekambrijumskim kristalastim stenama. Kod sva tri leţišta ugalja se javljaju više slojeva različite debljine, u okviru kojih se nalaze klastični sedimenti (gline, peskovi i dr.). U podini ugljenog basena nalaze se kristalaste stene prekambrijumske starosti. Teren u okolini leţišta uglja karakteriše se umereno kontinentalnom klimom, sa izuzetno niskim količinama padavina, toplim i sušnim letima i dosta hladnim zimama. Hidrografska mreţa je slabo razvijena, a glavni vodotok je CrnaReka koja predstavlja sliv svih vodotoka neposredne i šire okoline terena. Obod terena čine visoke planine (Selečka, Baba, Nidţe i Ilinske planine), sa nadmorskom visinom vrhova i preko 2000 metara. U hidrogeološkom pogledu dominira zbijeni tip izdani formiran u peskovitim sedimentima koji se nalaze ispod, izmeĎu i iznad ugljenih slojeva, gde predstavljaju tzv. podinske, meĎuslojne i krovinske izdani. Po hemijskom sastavu podzemne vode u neogenom kompleksu su preteţno hidrokarbonatne klase natrijumske, kalcijumske ili magnezijumske grupe. U pojedinim delovima basena sreću se tipične mineralne ugljokisele vode sa visokim sadrţajima gasa CO2. U formiranju rudničkih voda u postojećim rudarskim radovima, dominantan uticaj imaju podzemne vode iz izdani u peskovitim neogenim naslagama i atmosferske vode koje se direktno izlučuju u nebranjena područja površinskih kopova. Odvodnjavanje rudnika uglja vrši se kombinovano, pomoću obodnih kanala za prihvatanje površinskih voda koje se slivaju sa padinama, kanala za prihvatanje vode po etaţama kopova i drenaţnim bunarima kojima se zahvataju podzemne vode pre doticaja u rudarske radove. Eksploatacija uglja zajedno sa odvodnjavanjem rudarskih radova u značajnoj meri utiče na ţivotnu sredinu. rudnicima u značajnoj meri je uticala na ţivotnu sredinu. Negativan iii uticaj pomenutih aktivnosti ogleda se u degradaciju prirodnog reljefa i hidrografske mreţe, kontaminaciji vode, vazduha i zemljišta, izmeni reţima podzemnih i površinskih voda, kao i izmeni flore i faune...Coal deposits of “Suvodol”, “Brod-Gneotiono” is being exploited, while the coal deposit “Zivojno“is in a preparatory phase. It is situated in the further south-eastern and southern part of Pelagonija valley. The three coal deposits are made in Neogene sediments in lake terms of sedimentation, the zone of contact with Precambrian crystal rocks. In these three coal deposits, the coal is found in many layers with different depth in the bay where clastic sediments are found (clay, sands, etc.)In thesubstratum coal basins are found crystal rocks of Precambrian age. The terrain in the surrounding coal deposits is characterized with moderate continental climate with extremely low quantities of precipitation, warm and dry summers and quite cold winters. The hydrographic network is poorly developed and the major flow is River CrnaReca which is a basin of all flows in the immediate and wider surrounding terrains. Circumferential terrains make high mountains (Selečka, Baba, Nidţe i Ilinsk mountains) with a peak's alltitute of over 2000 meters). In hydrogeological point of view an aquifer is formed in sand sediments which are situated under, between and above coal layers which compose the so called substratum (beneath),interlayer and substratumaquifers. Ground water in Neogene complex is largely hydro-carbonate class of sodium, calcium and magnesium group in their chemical composition. In some parts of the basin, typical mineral coal acidic water with high content of CO2 gas could be found. A dominant influence in the formation of mining water in existing mining works have ground waters from aquifers in sandy Neogen sediments and precipitation water which is directly excreted fromopen areas of surface pits. Drainage of coal mines is combined, with circumferential channels for acquisition of surface water which flows from the slopes, the channels for acquisition of water in layer’s pits and drainage wells which get hold ofground water before its flow in mining works. Coal exploitation as well as the coal drainage works has quite an influence on the environment. Coal mines have rather an influence on the environment. The mentioned v activities have a negative influence on degradation of the natural relief and hydro geographic network, contaminated water, air and land, change of regimes and surface water as well as modifications in the flora and fauna..