Çeltikçi kömür sahası pasa kayaçlarının kayaç-su tepkimelerine bağlı çevresel etkilerinin araştırılması, Ankara - Türkiye

The purpose of this research is to investigate the water-rock interactions related acid rock drainage potential, leachate chemistry and related processes under test conditions using potential waste rock samples (Bostantepe I, Lower Çavuşlar II and Upper Çavuşlar III) of Çeltikçi formation coal deposit and to predict the drainage leachate chemistry under atmospheric given pile conditions. Mineralogic, static (acid base accounting, net acid generation) test, short-term leach test and long-term kinetic test data are collected for the investigation. The samples include silicate, oxide and hydroxide types of minerals in addition to clay, carbonate, sulphate and sulphide minerals. The ARD potentials of test samples are in the order of I>II>III and do not have acid rock drainage potential in short and long terms. Low-high metal release could occur according to the short term and kinetic leach tests. Relatively high concentrations of As, Mo and SO4 are detected. Hydrogeochemical modeling results based on prefeasibility pile assumptions and no remediation implementations suggest that pile leachates could be in acidic character under closed CO2 equilibrium conditions and in basic character in equilibrium with atmospheric CO2 conditions. The maximum environmental quality limits of Al, As, Fe, Pb, V in all simulated leachates and Cd/Cr/Zn parameters in some simulated leachates for the closed CO2 equilibrium conditions and As, Si, V in all simulated leachates and Cd/Pb/Zn parameters in some simulated leachates for the atmospheric CO2 conditions are exceeded. Gradual conditions between the closed CO2 and the open to atmospheric CO2 cases would probably be developed under the field conditions. Sensitivity analyses indicate that concentrations show in general slight tendency to decrease when the infiltration amount increase, the number of rainy days decrease and the SI criteria decrease. Keywords: Çeltikçi coal field, Acid rock drainage, static, kinetic, leach tests