Modern-day gold mining

There’s still gold in them thar rivers, and adventurers still cherish dreams of wealth. These days, though, sifting for gold is more a form of recreation than a business, and the tin pans have mostly been replaced by motorized machines called suction dredges. And the competing claims aren’t over who has prospecting rights, but whether this form of mechanized gold hunting is causing irreparable harm to rivers in Northern California and the fish that swim in them.

In 2011, Gov. Jerry Brown signed legislation that imposed a moratorium on the practice until 2016, by which time the state Department of Fish and Game was to adopt regulations that eliminated the potential for significant environmental damage and that set permit fees high enough to cover the state’s costs. The regulations adopted last month fall sadly short on both fronts.

Even in the early days, panning for gold wasn’t an environmentally clean venture. Gold hunters often used mercury to make it easier to separate out the precious metal. Since then, river flow has entombed the toxic mercury under silt and stone.

Enter the modern suction dredge, which vacuums sand, gravel and stones from the river bottom, then sends it all through a floating sluice where the gold, heavier than the rest of the material, sinks and is trapped, while the remainder is returned to the river. In the process, the dredge unearths the mercury and releases it into the water. In addition, dredging often fills the spaces between river rocks with silt and sand. Those spaces help oxygenate the water and provide habitat for insects that salmon and other fish eat. Dredging also clouds the water with sediment.

Both theU.S. Environmental Protection Agencyand the State Water Resources Control Board expressed serious misgivings about the new regulations and suggested that an ongoing moratorium was the policy best supported by science. The rules reduce the number of permits from the previous 3,000-plus a year to 1,500, but they don’t resolve the most serious environmental problems. And the proposed permit fees fall short of covering the real costs.

The Karuk tribe, which lives along the Klamath and other affected rivers, sued this week, along with environmental and sport-fishing groups, to overturn the regulations. In their report, Fish and Game officials concede that the new rules will allow “significant and unavoidable environmental impacts” that are “not acceptable” but say their authority to do better is limited by law. That assertion is debatable, but in any case, the courts should reject these less-than-golden regulations that fail to meet the requirements of the state law.