By Christopher Peltz
For the Silverton Standard
With more than 130 years of mining activity in San Juan County, there are hundreds of mine shafts, waste rock piles, and mill tailings.
The combined effect of all these sites, along with the highly acidic rock in the region has created some significant negative impacts on the local river systems and hillsides.
The biggest impacts to the local environment relate to the erosion of the highly mineralized waste rock and mill tailings and the chemical pollution in the streams that this leads to. Over the years, many studies have been conducted, and many techniques have been tried to reduce the sources of this pollution and effects of it, all with mixed results and often with very high cost.
Mountain Studies Institute (MSI), along with collaborators from the Forest Service and Bureau of Land Management are trying a new tactic to restore some of the many abandoned mine sites to a condition which would allow natural processes to slow the erosion and potentially keep the chemical pollution out of the rivers.
The restoration technique they are employing is a novel method, where the application of a black carbon-based soil amendment called Biochar, is applied to waste rock piles and mine soils. The special properties of Biochar, could potentially make it a cost effective alternative to some of the more intensive efforts now used to clean up mine sites.
Currently MSI is receiving its Biochar from a company in Golden — Biochar Engineering (www.biocharengineering.com) but the hope is that soon the Forest Service will be able to produce Biochar locally from dead or thinned logs.
MSI scientist Chris Peltz along with MSI staff and summer interns have been running experiments at mine sites all around Silverton this past summer to determine the best methods for using Biochar and under what circumstances the highest return on effort would yield. Preliminary results suggest that the Biochar has a positive effect on both reducing soil compaction and water retention capacity.
The experiments will run for another year and include soil chemistry analysis and container trials to see if the Biochar has a significant impact on the potential for native grass varieties to grow.
For those interested in hearing more about these experiments or who are interested in learning more about some of the science projects MSI is engaged in, there is a Climate Conference being hosted by MSI early next month (Oct. 6-9) and at this conference there will be a tour of one of the Biochar mine sites.
For more information please contact Chris Peltz firstname.lastname@example.org