While silver minerals are very inconspicuous at best and no longer found in outcrop or in the mine dumps, sandstone stained by green and blue copper carbonates is fairly common. Doubtless it was this much more visible sign of mineralization that led prospector John Kemple to assay several samples and to discover not only copper but also significant silver in these rocks.
Between 1996 and 2000, the State of Utah spent considerable effort at reclaiming the mining district, an important goal given the nearby residential development and hundreds of open mine shafts and tunnels.
Ironically, the district's historical status and other constraints made normal reclamation goals impractical. While reclamation efforts usually strive to make the mining disturbance disappear, at Silver Reef the goal was to preserve the mining disturbance while keeping the reclamation invisible.
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In 1996 and 1997, the Utah Division of Oil, Gas and Mining, Abandoned Mine Reclamation Program (UAMRP) identified Silver Reef as a priority for reclamation due to its growing residential development. The program sealed 465 mine openings at Silver Reef, and in 2000 completed reclamation of the East Reef area.
The projects broke new ground in interdisciplinary teamwork as biologists, engineers, historians, and the construction contractor worked together to solve complex technical and legal issues. The Silver Reef mining district is a “rural historic landscape” eligible for the National Register of Historic Places.
It is also home to the state’s third-largest Corynorhinus townsendii (Townsend’s big-eared bat) maternity colonies, a species of bat considered imperiled in the state. The district is sandwiched between two subdivisions whose residents regularly explore the area.
Finally, mine openings are numerous, closely spaced, and have a variety of configurations, which made precise site identification and mapping mandatory. Ironically, the historical status and other constraints at Silver Reef forced the UAMRP to toss normal reclamation convention on its head.
While reclamation efforts usually strive to make the mining disturbance disappear, at Silver Reef the goal was to preserve the mining disturbance while keeping the reclamation invisible.
The majority of mines were closed by backfilling, mostly by hand to minimize the effects of heavy equipment on the landscape.
Significant care was taken to preserve the appearance of nearby dumps, and in many cases, the fill was recessed slightly below grade to eliminate the fall hazard but maintain the appearance of the opening and collar features.
Because of both cultural and biological concerns, the projects made extensive use of steel gates and grates, including the 42 by 47 foot, grate over the ASARCO shaft. The ASARCO shaft was dug in 1929 by the American Smelting and Refining Company. The shaft is 540 feet deep shaft and connects to the old Savage Mine at Buckeye Reef and to the Leeds Mine at White Reef. ASARCO drained the old mines and re-evaluated the district’s potential, but dropped the option in the early 1930s.
Grates allow bats to come and go and they maintain ventilation in the mines. Grates are visually unobtrusive, can be fitted around historic elements of an opening, and do not require raiding the dump for materials.