United States Forest Service Abandoned Mine Land Inventory Project
The Colorado Geological Survey completed an inventory of environmental degradation associated with abandoned and inactive mines on National Forest System lands in Colorado during the years 1991 through 1999. In the course of the inventory, areas with natural acid rock drainage were also noted. Approximately 18,000 abandoned mine-related features were inventoried, including about 900 features that are considered significant enough environmental problems to warrant further investigation. Water quality data, such as pH and conductivity were gathered at all features where water was present, such as draining adits, seepage at the toe of dumps and tailings, and standing water in shafts. Water samples were taken where field tests indicated low pH and/or high conductivity, including several areas with natural acid rock drainage. Samples were analyzed for dissolved and total metals, and for selected anions. All mine locations and data collected by the field geologists were entered on field forms and, subsequently, into a computer database and GIS format.
With the information provided by the inventory, the Forest Service, in cooperation with other agencies, has been able to prioritize abandoned mines for reclamation. In most cases, cleanup is approached on a watershed basis. Mines in priority watersheds were selected for reclamation first. Watershed studies and mine cleanup are taking place or have been completed in the upper Animas River, Willow Creek (tributary to the upper Rio Grande), Chalk Creek (tributary to the upper Arkansas River), the upper Snake River, the Uncompahgre River, the Alamosa River, and additional Colorado watersheds.
During the inventory, evidence of natural water quality degradation was found in areas where little or no evidence of mining activity exists. These areas include the upper Alamosa River, the Middle Fork of Mineral Creek, Peekaboo Gulch, Handcart Gulch, and elsewhere. Water from natural sources has been found to exceed Colorado water quality standards significantly for several metals in these areas and must be considered in reclamation decisions and remedial activities.
Downloadable Data (Below) Overview:
The USFS AMLI Project can be accessed using .kml files and Google earth or through a File Geodatabase with ArcGIS. To use the .kml files simply download the Mine Sample, Water, and Photo .kml files along with the either the Environmental Hazard or Physical Hazard Area, Opening, and Pile .kml files and open all six .kml files in Google earth. The basic structure of the data is as follows:
Mine Area.kml - Contains information about location, topology and general characteristics of the mining area.
Mine Opening.kml - Contains information about the condition, access deterrents, water drainages, dimensions as well as other features of the mine opening. Openings are assigned an ID number ranging from 100-199 in each mining area.
Mine Pile.kml - Contains information about the condition, access deterrents, water drainages, dimensions as well as other features of the each mine areas mine dumps or tailing piles. Piles are assigned an ID number ranging from 200-299 in each mining area.
Mine Water.kml - Contains information about the water samples conducted in the field within the mining area. This includes the pH, conductivity, discharge rate, biological effects of water contamination, ect. Water are assigned an ID ranging from 300-399 in each mining area.
Mine Water Sample.kml - information about all water samples taken for laboratory analysis. These records have the same ID as their corresponding Mine Water features.
Photos.kml - these are the photos taken of the various features within each mining area. The photos are labeled with the primary feature they depict (as they may depict multiple features).