PROPOSED ROYAL JOHN MINE TAILINGS REPOSITORY: GROUNDWATER AND CAVE ASSESSMENT

The Royal John Mine was first developed in the 1800s on the Gila National Forest. The mine is located at approximately 8,000 feet (2,400 meters) in elevation adjacent to the headwaters of the Mimbres River in the Mimbres Mountains of southwest New Mexico. It advanced into a group of mines developed by a succession of owners mainly for zinc, silver, and lead through 1969. In the center of this mining area sits Royal John Cave, a hypogene cave in Pennsylvanian limestone which consists of 1,000 feet (305 meters) of mapped passage including a large lake room and a natural spring entrance. Archaeological artifacts related to the mine as well as the Mogollon people were found in and surrounding the cave. Local cavers enjoy visiting the cave, however the easiest access is through a mining adit which intersects the cave. The Royal John mine adits are all on U.S. Forest Service land, however there is an adjacent patented mining claim which contains many mining artifacts and buildings, as well as the spring and natural entrance to Royal John cave.

Over two acres (.8 hectares) of mine tailings are located along the main drainage, Cold Creek, and more tailings and waste rock are located near the adits around the area resulting in high values for lead in the surrounding water and soils. In the 1990s, efforts by the U.S. Environmental Protection Agency worked to stabilize tailings and prevent leaching in Cold Creek through reconstruction of a drainage channel, creation of sediment control, and addition of vegetation. These efforts were unsuccessful. In 2013 a fire swept across the area, resulting in higher streamflow during the monsoon period. These high flows eroded the reclamation efforts, exposing tailings in the stream. In 2017 the Forest Service is working to create a repository for the waste rock and tailings, and two proposed sites have been located, one in the West Cut area. The main purpose of this portion of the project was to discuss groundwater issues surrounding the repository, as well as issues relating to cave management of Royal John Cave.