This 216-page report and 8-page executive summary are the result of the first phase of The Sierra Fund’s Malakoff Diggins Project, more than five years of collaborative science-based data collection, research, and analysis at Malakoff Diggins State Historic Park (MDSHP), part of the California State Parks system.
Click here to view the full report.
Click here to view the 8-page executive summary.
Key partners in this project, in addition to State Parks, include CSU Chico Geological & Environmental Sciences Department, Sonoma State University Archeology Department, California Department of Conservation/Abandoned Mine Lands Program (DOC/AMLP), Sierra Nevada Conservancy, and the South Yuba River Citizens League.
The report outlines an assessment of the various physical and chemical characteristics of this legacy hydraulic mining park, including the pit or “diggins”; tunnels and shafts from the old mining operation; and the discharge from these features into downstream watersheds. The assessment portion of this Report used a variety of methods to learn about the nature of the pit itself as well as the Humbug Creek (into which the “diggins” discharge) including:
- Historical research into mine operations prior to state acquisition (roughly 1850s – 1960s)
- Sampling of soil and water and testing by EPA-certified laboratories
- Continuous stage and turbidity recording to calculate annual loads
- Event-based storm sampling for total suspended sediment and mercury
- Physical surveys of the pit and surrounding area using GIS
This report presents management recommendations about how to mitigate the physical and chemical hazards assessed by this project. This includes a provisional review of potential impacts under CEQA to identify studies needed to potentially permit the scenario of management recommendations outlined in the document.