California Indian tribes and environmental groups are preparing for a showdown with the state Department of Fish and Game and recreational miners who use suction dredging operations to find gold.
The Nevada City-based group Sierra Fund is supporting the Karuk tribe on the Klamath River and in urging Fish and Game to stop issuing suction dredging permits until more scientific study can determine the health impacts of dredging on fish and the people who eat them.
Every year, the state issues 3,500 suction dredging permits.
In the Sierra Nevada, mercury left from mining operations 150 years ago remains in a number of reservoirs and rivers. Health advisories have been issued for a number of popular fishing spots in Nevada County, including Lake Englebright, Camp Far West Reservoir, Combie Reservoir and Rollins Reservoir, according to the California Office of Environmental Health Hazard Assessment.
Suction dredging operations are a regular sight in the Yuba River along Highway 49 in Sierra County.
Suction dredging uses a vacuum hose to suck gravel and sand from the riverbed in the search of gold. The activity can stir up Gold Rush-era mercury from the sediment and may increase the occurrence of methylmercury, a form of the heavy metal that can lodge in the fatty tissue of fish when consumed, said Mike Thornton of the Sierra Fund.
"It's incredibly toxic and works its way up the food chain. If (people) eat enough of it over time, it leads to serious health impacts," Thornton said.
In 2008, the group warned of the dangers of releasing mercury into the environment in the report "Mining's Toxic Legacy." Organizers now are urging people to send letters in support of SB 670, a bill introduced by state Sen. Pat Wiggins placing a moratorium on suction dredging until a full scientific review is complete.
Last year, the Bureau of Land Management halted suction dredging along a section of the South Yuba River while scientists study the liquid mercury found in the sediment below Humbug Creek.
On Combie Reservoir, the Nevada Irrigation District is conducting a pilot program to remove mercury trapped in the sediment behind the dam.
Fish and Game officials are studying the impacts of suction dredging, but an environmental report won't be complete until at least 2010, said spokesperson Jordan Traverso.
"There's not enough science to back us putting emergency rule-making in place to stop it," Traverso said.
Nevertheless, the state enforced severe fishing restrictions for salmon last year because of a "collapse" of the fishery and early indications by federal regulators show that a similar low return of spawning Chinook salmon is expected again this fall.
"If we're going to have fishing restrictions, we should have mining restrictions," said Craig Tucker of the Karuk Tribe. "We don't understand why the government is going to bat for 3,000 gold miners."
The Karuk tribe lives on the Klamath River near Happy Camp and fishes for salmon.
Suction dredging can disrupt the salmon beds, or "reds," where salmon deposit their eggs. It also harms the habitat of Pacific lamprey eels, which tribal members like to eat barbecued, Tucker said.
In February, the tribe filed a lawsuit against Fish and Game claiming that taxpayers' dollars are subsidizing the mining program that does not support itself from permit revenue alone.
Traverso says that could be said of many of the agency's programs that have been supported more by general fund revenue than fees in recent years.
While the battle between recreational miners and the Karuk tribe is nothing new, the fight has heated up in recent months with a steady firing of petitions and lawsuits from both sides.
In December, the Karuk tribe filed a petition urging the state to halt dredging, a move that spurred The New 49ers, a recreational mining club also based in Happy Camp, to file a petition that argued the tribe was responsible for "widespread and wanton" killing of salmon by using dip nets. Fish and Game denied both petitions.
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