Describes the history, geology, and environmental setting of selected mines near Ophir in San Miguel County. Includes: forward, abbreviations and symbols, introduction, site location, previous investigation, geologic setting, historical overview, North Chapman Gulch mine, drill hole Chapman Gulch, Chapman Gulch mine, Carbonero area, New Dominion mine, Carbonero tailings, Carribeau mine, natural sources of metal, migration pathways, summary and conclusions, references, and appendix. Digital PDF download. OF-02-13D
From the authors notes:
During the summer of 1996 the Colorado Geological Survey (CGS) inventoried mines in the Ophir (Iron Springs) mining district in the Howard Fork of the San Miguel River drainage basin as part of a Statewide inventory of abandoned mines on or affecting U.S. Forest Service administered lands in Colorado. In 2000 the U.S. Forest Service requested more detailed information regarding selected inventoried mine features, the Carribeau Mine, and the Carbonero tailings. The Carribeau Mine and Carbonero tailings were not included in the 1996 inventory because U.S. Forest Service Primary Base Series (PBS) maps suggested that these sites were on private land. However, a survey in 2000 showed that the draining adit at the Carribeau was on National Forest System (NFS) land. Although not surveyed, a small portion of the Carbonero tailings pile probably extends onto NFS land, too.
In addition to the Carribeau Mine and Carbonero tailings, selected mine features in the North Chapman Gulch (254/4194-1), Chapman Gulch (253/4194-1), Drill Hole-Chapman Gulch (253/4194-3), Carbonero Area (252/4194-1), and New Dominion (251/4193-1) inventory areas are described. CGS assigned Environmental Degradation Ratings (EDRs) of 3 (potentially significant) or worse to some of the mine features in those inventory areas. The following report describes sites beginning upstream in Chapman Gulch and progressing downstream to the Carribeau Mine.