Report on the occurrence of the acidulous waters below the final slope of the ČSA open-pit (Most Basin)

Abstract

Three springs of acidulous water were found in the area of the deep lignite mining, which began in 2014 in the ČSA open-pit (Albrechtice near Most cadastre). One spring (JZ 163) flowed directly from the casing of the exploratory well, cut slightly above the adit floor. Two other sources (CH1 and CH2) were springs directly in the coal seam. The springs represent Na-HCO3 (JZ 163), Na-HCO33-SO4 (CH1) and Na-Ca-SO4-HCO3 (CH2) hydrochemical type of waters. Their total mineralization varied between 2.3 to 2.8 g/L and the temperature was of up to 29.1 °C. In all cases, the springs were accompanied by massive CO2 outflows. The described occurrence belongs to the northern belt of the acidulous waters underneath the Krušné hory Mts. (Erzgebirge Mts.), linking the important localities of carbonated waters in Klášterec nad Ohří and Bílina located along the Eger Rift. The mine was closed on 27 April 2020 and the site is no longer accessible.