Zmiany składu chemicznego wód podziemnych w węglanowych utworach triasu opolskiego na podstawie badań wybranych źródeł

Results of research of six large karstic springs with a discharge rate of 10-100 l/s obtainedfrom a series of 12 measurements in 2021-2022 are the basis for a comparison of the chemical composition in the past and present. The studied springs drain Triassic limestones and dolomites in the southern part of Major Groundwater Basin No. 333 in the Opole region. After 40 years, there is a significant decrease in discharge rates in five out of all selected springs, and frequent dying out of outflows in three cases. A significant increase in the content of nitrogen compounds, espe¬cially nitrates, has been measured. Statistical factor analysis allowed distinguishing two groups of factors responsible for changes in the main ions in groundwater. Restoring high groundwater quality is an urgent task for the administration of this region, which requires a comprehensive approach.