Small Scale Dredging
Small scale dredge mining is often done with the operation of a suction dredge to mine for gold at the bottom of a streambed. Suction dredging can be likened to using an underwater vacuum cleaner – to suck up material from a river or stream bottom. The machine runs the material through a separation system, usually a sluice box, to recover the valuable materials. The remaining sediment and gravels end up back in the river.
Small scale dredge mining has the advantage of removing mercury from the river systems. This mercury was left from historic hydraulic mining practices in the Sierra Nevada Mountains that occurred from about 1853 to 1884. At that time, mercury was used to amalgamate and recover gold, and a significant amount of the mercury used by miners at the time (about 1/10th), ended up in lost in the process and deposited in the rivers.
Certain special interest groups are attempting to ban dredging in California under the premise that recreational dredge mining stirs up mercury and negatively impacts fisheries and the Environment. This could not be farther from the truth. Small scale dredge miners remove no only mercury, but garbage, lead shot (sinkers from fishermen), lead bullets (from hunters), and other materials from the rivers and ultimately improve their condition for fish, macroinvertabrates, and other aquatic animals.
The Sierrans for Responsible Resource Development (the "Sierrans") believe that small scale dredging can be done responsibly and is one of the few ways to potentially clean up historic mercury left from hydraulic mining in the mid 1800's. Small scale mining, including gold panning, and sluicing should continue to be allowed and promoted in California for small scale miners and should be encouraged as a recreational and tourism attraction for the State.