An environmental group is suing the state over an environmental report that could pave the way for an increase in sand mining in San Francisco Bay, saying the study fails to take into consideration the ?erosion at Ocean Beach.
Last month, the California State Lands Commission approved the environmental review for two sand mining permits in San Francisco and Suisan bays. Two companies — Hanson Aggregates Marine and Jerico Products — are seeking a 17.4 percent increase in the amount of sand they can remove over a 10-year lease on the state-owned land.
San Francisco Baykeeper, an environmental advocacy group, filed a lawsuit Nov. 16, arguing that the environmental review did not adequately evaluate the impact of Bay sand depletion on coastal erosion.
People have removed sand from the Bay for more than 100 years to clear harbors and channels and, more recently, obtain construction material. It was assumed that the sand replenished itself.
But scientific studies now show that only 15 percent of the sand mined for construction material is replenished. That decrease partially stems from the reduction in sediment from Gold Rush-era hydraulic mining in the Sierra Nevada mountains. Dams and flood control measures also have reduced the water and sediment flow through the delta and into the Bay.
Patrick Barnard, a coastal geologist for the U.S. Geological Society, said the decrease in sediment replenishment is one of the causes of erosion at the southern portion of Ocean Beach, which is threatening valuable city infrastructure, including Great Highway and a water treatment plant worth hundreds of millions of dollars.
Ian Wren, a staff scientist at Baykeeper, said the lawsuit is asking for the state to ensure that the environmental review reflects the impacts to Ocean Beach.
“We are not saying that sand mining should be done away with altogether,” Wren said.
Lands Commission Executive Director Curtis Fossum said the environmental review was done over the course of many years and was thoroughly vetted by staff. He said the review was limited to the specific part of the Bay where the sand mining would occur.
“We stand by the commission’s actions,” he said of the lawsuit, which he had not seen Wednesday.
In response to a question about what new research suggests about the impact of Bay sediment depletion, Fossum said, “People can come up with new information at any minute.” He said his agency has to balance conflicting expert opinion and recommend what is best for the state.
Peter Baye, an independent coastal ecology consultant, has recommended that mining be decreased to the rate of sand replenishment. That would result in a drastic reduction in the amount of sand removed, not the increase the two companies are seeking.
Alternatives to mining bay sand include mining it from local land-based sources or shipping or trucking such material in from glacial deposits, mostly in British Columbia. Both, however, could increase greenhouse gas emissions.
Spokesmen from both sand mining companies recently told the San Francisco Bay Conservation and Development Commission that sand mining from the Bay is less ?expensive and more ecological.
The mining permits will require approval from several federal, state and local agencies.