Reclaiming the Sierra 2012 included a full day of technical tours on Friday, May 4.
Read more details on the following tours below:
- Malakoff Diggins/Humbug Creek Assessment
- Nevada City Brownfields/Tribute Trail
- Spenceville Mine Remediation/Yuba Gold Fields/Hallwood Gravel Operation
- Grass Valley/Empire Mine
Malakoff Diggins/Humbug Creek Assessment
Malakoff Diggins, only 20 miles from Nevada City, is the site of the world’s largest hydraulic mine, now a California State Historic Park. Litigation against the mine in 1879 resulted in the historic “Sawyer Decision” and the country’s first environmental law. Malakoff Diggins is a spectacular site to visit, with its one- by two-mile pit, carved by water cannons, the historic town of North Bloomfield, and tunnels (one 7,847 feet through bedrock) engineered to drain the diggings.
This all day tour featured a tour of the Diggins with stops at a vista point, the town of North Bloomfield, the pit floor, and Hiller tunnel. The tour included walking up to a total of three miles, so bring water and sturdy shoes.
The Sierra Fund and State Parks are currently partnering to assess the ongoing impacts of the mine as it drains into the South Yuba Watershed, in order to create a management plan that will protect water quality while preserving the park’s enormous cultural significance. This tour included details on this multi-year project, and potential management strategies at the site.
This tour appeals to environmental science and cultural resource experts, as well as interested public and other disciplines as it provides a stunning example of the scale of impact of abandoned mines in the state.
Schedule & Speakers:
Participants met at the Miners Foundry at 8:45 am and board a bus that will depart at 9:00 am sharp. Participants toured the town site, then walked to the mine pit overlook, discharge point Hiller Tunnel, and pit pond. Along this route, Carrie Monohan and Rick Humphreys discussed the history of the mine operation and the current impacts it has on the watershed. Tour leaders discussed The Sierra Fund and California State Parks’ current assessment work that will result in a management plan for the watershed. Dave Brown of California State University Chico spoke about the graduate and undergraduate level research focused on this site. Peter Graves discussed the current assessment project on BLM land at the convergence of Humbug Creek and the South Yuba River. The bus returned to the Miners Foundry by 4:30 pm.
Nevada City Brownfields/Tribute Trail
Nevada City was the “Queen of the Northern Mines” and features several excellent examples of ongoing mining impacts on human health, native peoples, and community development projects. This was a walking tour of 4 miles.
Schedule & Speakers:
The Tour was led by Jason Muir of local environmental consulting firm Holdrege & Kull. The tour proceeded out of town along the recently completed Deer Creek Tribute Trail, a community project that involved several local organizations and agencies, which The Sierra Fund served as fiscal sponsor. Along this route:
- Kyle Leach, a consultant working with The Sierra Fund and other local groups, discussed the former mine sites in Nevada City that received funding from the EPA Brownfields Program for assessment and cleanup.
- Eric Jorgensen of the Greater Champion Neighborhood Association talked about the community’s vision for a trail and obstacles encountered building a trail through areas that were previously mined.
- Shelly Covert of the Nevada City Rancheria discussed the impact of Gold Rush mining activities on the native peoples of the area, and their current efforts to restore native culture and ecology.
- Sherri Norris of California Indian Environmental Alliance points out the human health impacts of toxins left from the Gold Rush, particularly on native peoples, as well as the importance of fish consumption awareness among local sustenance fishers and native peoples.
After lunch Jason Muir gave an overview of the BLM preliminary site investigation at that site, also known as Stocking Flat, and BLM trail portions. Jacob Fleck of USGS discussed the current research on mercury fate and transport at the Stocking Flat site. The tour concludes at the Chinese Tribute bridge at 2:00 pm.
Spenceville Mine Remediation/Yuba Gold Fields/Hallwood Gravel
The Spenceville Copper Mine, located within the Spenceville Wildlife Refuge 20 miles from Nevada City, was reclaimed by the California Geological Survey, working with California Department of Fish and Game, the Regional Water Quality Control Board, and UC Davis. The project earned the Governor’s Environmental Leadership Award. This tour included a stop at the mine site, and details on how toxic mine waste and acid mine drainage were addressed and methods used to remediate the site.
This all day tour continued another 15 miles to the Yuba Gold Fields, a 10 square mile gravel wasteland on both sides of the Lower Yuba River where hydraulic mining debris from Malakoff Diggins and other 19th century mines in the Yuba watershed was deposited. Hydraulic mining used more mercury than any other kind of historic mining method, so a great deal of mercury is also likely present along with the hydraulic mining debris.
This area has been repeatedly re-mined for gravel and gold over the last 75 years, and is currently the site of several gravel operations. The tour discussed the history and current use of this area, as well as the potential for cleaning up mercury as part of a routine gravel mining operation.
The final stop on the tour was Teichert Materials’ Hallwood Plant, which currently mines gravel and sand from the Gold Fields near Marysville. Participants learned about the history of this site, the current gravel operation, and award-winning reclamation completed.
Schedule & Speakers:
The first stop was the Spenceville Wildlife Refuge owned by the CA Department of Fish and Game in western Nevada County where an abandoned copper mine was recently remediated. Stephen Reynolds, CEG, CHG with the California Geological Survey, who led this remediation activity, discussed the problems encountered at the site and the process of the remediation. Ralph Hitchcock with the Friends of Spenceville added details about their organization’s experience working with this remediation effort. After lunch, participants boarded the bus to travel to the Yuba Gold Fields, an area where millions of cubic yards of debris from upstream hydraulic mines were deposited in the 19th century. Gary Reedy of the South Yuba River Citizens League discussed opportunities for restoration of this area, and his organization’s efforts. The final stop on the tour will be the Hallwood Plant, a Teichert Materials gravel operation in the Gold Fields. John Lane of Teichert Materials led a tour of this plant.
Grass Valley/Empire Mine
Grass Valley, only four miles from Nevada City, was home to some of the most productive gold mines in California. Today, there are 3,600 former mine features within the city limits alone. In particular, the Empire Mine (now a popular State Historic Park) was the richest hard-rock mine in the State of California producing 5.8 million ounces of gold in its operating history of 106 years (1850-1956).
This all day tour featured ongoing and completed mine restoration projects in Grass Valley, the human health hazard assessment of naturally occurring arsenic in this area, and a visit to the excellently preserved mine yard and grounds at Empire Mine State Historic Park.
Schedule & Speakers:
At 9:45 am, tour participants met in the parking lot of the Empire Mine Visitors Center/Main Entrance. Participants then walked 0.25 miles to the Magenta Drain Passive Treatment System settling ponds on Empire Street. William Agster of Golder & Associates and Dan Millsap of California State Parks described the mine drainage problem and solution that the Passive Treatment System offers. Ralph Silberstein of CLAIM-GV discussd mine impacts in and around Grass Valley and the work of local organizations to protect and restore the watershed. Participants then returned to the main entrance of the Park where a box lunch was provided. A representative of the Empire Mine Park Association gave the group a private tour of the mine yard and entrance to the underground workings. Finally, participants took a short walk to a series of hard rock waste rock piles on the Empire property and hear a discussion led by Charlie Alpers of USGS and Valerie Mitchell and Perry Myers of Dept. of Toxic Substances Control about arsenic exposure problems at the park, remediation efforts, and the ongoing study of arsenic bioavailability using samples from the park.
Sixteen to One Mine
Unfortunately the Sixteen to One Mine Tour was cancelled.