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Rico Argentine Mine

Site Contact:
Paul Peronard
On-Scene Coordinator


Site Location:
Rico, CO 81332

The Rico Argentine Mine Site includes the historical water treatment settling ponds and associated waste, and it includes historic mine working associated with the St. Louis Tunnel. The Site is adjacent to the Dolores River and extends into Telescope Mountain and its related mine workings. The St. Louis Tunnel Adit and settling ponds are located on the eastern edge of Dolores County approximately ½ mile north of the town of Rico. The settling ponds area is on the eastern bank of the Dolores River and occupies about 80 acres along the flood plain. The adit discharge is approximately 1.5 to 3 cfs (or 600 to 1300 gpm) seasonally. The settling ponds contain metals precipitate sludge that has remained onsite since water treatment operations stopped around 1996. Currently, of the 19 original settling ponds, only 10 are actively receiving water discharged from the adit. High concentrations of metals and acidic water are present in the upper workings that drain to the St. Louis Tunnel discharging to the Dolores River.

For additional information, visit the Pollution/Situation Report (Pol/Sitreps) section.