The research in question analyzes the impact of mining wastewater on the quality of surface water of brown coal mines. Through careful statistical and chemical analysis, key parameters in surface water were investigated before and after the discharge of wastewater into surface water. The results indicate statistically significant variations, especially highlighting nitrates, nitrites, and sulfates. Identified periods of deviation provide the basis for the precise application of preventive and corrective measures. The results of the research are important not only for the mining industry but also for the preservation of ecosystems in the vicinity of brown coal mines. Targeted guidance of water treatment according to identified parameters provides practical guidelines for increasing treatment efficiency, with long-term positive effects on water quality and biodiversity preservation. The research contributes to a comprehensive understanding of the impact of mining activities on surface waters, providing scientifically based data for informed decision-making of mining operations and the preservation of aquatic ecosystems.