Multiple sources of mine drainage including discharge from the abandoned Dinero mine tunnel and two gulches flow into a wetland, known herein as the Dinero wetland along the Lake Fork Creek corridor. The Dinero wetland is approximately 20 acres in extent. The Dinero wetland is being considered as a location for passive treatment of the mine drainage flowing through it. As such, study objectives are to understand: (1) variations in pH, specific conductance, and temperature in surface water in the wetland; (2) metal loading into and out of the wetland; (3) the configuration of surface drainage features; (4) the configuration of subsurface conductive features; and (4) depth to bedrock in the wetland. These data will be used to help understand whether the wetland is currently and naturally treating the mine drainage flowing through it and will help pinpoint locations needing additional investigations to help inform potential passive treatment scenarios. Three self-potential (SP) surveys were completed around the Dinero Mine on Mount Massive, near Leadville, Colorado between August 21–25, 2023, and July 16–18, 2024. The first survey began in August 2023 and was completed in July 2024 in a wetland on the northeast flank of Mount Massive. This survey consisted of two-dimensional (2D) SP mapping done to identify preferential groundwater-flow paths between the Dinero Mine tunnel and Lake Fork Creek. The second survey was completed in August 2023 in the Lake Fork Creek stream. This survey consisted of SP data collection along a profile that began a few tens of meters downstream from Turquoise Lake dam and ended approximately 450 meters downstream to estimate locations where groundwater from the wetland discharged into the creek. The third survey was also completed in August 2023 on the Dinero Mine tailings pile at higher elevation on Mount Massive. This survey consisted of 2D SP mapping on the tailings-pile surface to estimate the location of the vertical shaft into the Dinero Mine that was buried beneath the surface.