Chemical Composition of the Extremely Alkaline Water within 'Gorka' Pit Lake (Chrzanow Region, South Poland)

摘要

Industrial pit lake "Gorka" was formed in inactive Jurassic limestone quarry after cessation of the open-pit dewatering. Main problem for water environment quality in this area is connected with 500.000 m~3 volume, extremely alkaline leachate gathered in flooded quarry. Average pH of the leachate from Gorka pit lake is between 11,5 and 13,4 with high concentration of sodium (2-6 g/L) and some microelements (Al, As, Cr, Mo, P and V). The water gathered within pit lake has a rare hydrochemical type Na-CO_3 or Na-CO_3-OH, with predominance of the sodium, bicarbonate and hydroxyl ions. The chemical composition of the extremely alkaline leachate was formed as a result of the groundwater contact with the industrial red-mud wastes containing about 5-10 percent of sodium carbonate.