The mining method uses a gas- or diesel-powered vacuum hose that sucks gravel and sand from the river's bottom, then unloads the material into a sluice box where gold particles can settle.
”The rest of the gravel and potentially toxic sediment is simply dumped back into the river,” the release stated. “Depending upon size, location and density of these machines, they can turn a clear running mountain stream or river segment into a murky watercourse unfit for swimming.”
At the same time, opponents say, the dredging disturbs spawning gravels, killing the salmon eggs and immature lamprey that live in the gravel.
”In a system like the Klamath where salmon can be stressed due to poor water quality, having a dredge running in the middle of the stream affects the fishes ability to reach their spawning grounds,” Karuk Tribe lead fisheries biologist Toz Soto said. “There is a lot of mercury settled on the bottom of these rivers from gold smelting operations from the 1800s. Dredging reintroduces mercury to the stream creating a toxic hazard for fish and people.”
The hope is the governor will agree with the temporary moratorium on suction dredge mining that the state Legislature included in the 2008-09 budget. In the meantime, the state Department of Fish and Game is overhauling statewide regulation of in-stream mining, according to the tribe.
”We need the governor to take a stand with Native People and the 2.2 million anglers in California -- not 3,000 recreational gold miners,” Karuk Tribal member Leaf Hillman said.