DAILY CHANGES TO THE EFFICIENCY OF THE WINGFIELD PINES PASSIVE ACID MINE DRAINAGE TREATMENT SYSTEM

Acid mine drainage (AMD) is a common problem in southwestern Pennsylvania due to regional abundance of abandoned coal mines. As water passes through abandoned mines, metals such as iron leach out and contaminate the water. Wingfield Pines is a passive treatment site for AMD located in Upper Saint Clair, Pennsylvania. The site consists of five settling ponds and a wetland that flows into Chartiers Creek. The contaminated water passes through each of the ponds and precipitates out metals. The goal of this project is to investigate changes to the efficiency of pond one in response to sunlight and temperature variation seen during a daily cycle. Dissolved Fe, Al, Cu, and Mn concentrations were measured at the entrance and exit points of pond one in the morning and again in the evening. Conductivity, pH, temperature, and sunlight intensity were also collected at these locations at the same times. Concentrations in dissolved Mn, Fe, and Al showed a minor decrease at the entrance from morning to evening though showed a more noticeable increase at the exit across the same time frame. Concentrations in Cu demonstrated the opposite trend. Overall, pond one demonstrated dissolved Mn, Cu, Fe, and Al concentration decreases by 33% (1.2 mg/L to 0.8 mg/L), 61% (0.87 mg/L to 0.34 mg/L), 89% (11.788 mg/L to 1.242 mg/L), and 100% (0.083 mg/L to not detectable) respectively from the entrance to the exit in the morning. In the evening, dissolved Mn increased by 33% (0.9 mg/L to 1.2 mg/L) and Cu, Fe, Al concentrations decreased by 82% (0.95 mg/L to 0.17 mg/L), 86% (11.644 mg/L to 1.642 mg/L), and 36% (0.039 mg/L to 0.025 mg/L) respectively from the entrance to the exit in the evening. This suggests pond one is less efficient in decreasing dissolved Mn, Fe, and Al concentrations in the evening than in the morning. Concentrations in Cu followed the opposite trend. These changes in efficiency are likely due to a response in sunlight intensity and temperature changes related to bacterial influence.