70-year mercury cleanup plan OK'd for S.F. Bay

Getting rid of enough mercury to make San Francisco Bay's fish safe to eat may take 70 years, under a plan adopted this week by state officials.

The cleanup plan focuses on some sources of the toxin -- old mines, businesses, sewage treatment plants and city streets -- and sets limits on how much mercury should be allowed to flow into the bay. The limits are based on how much the metal builds up in fish.

Residents who rely on contaminated bay fish for a part of their regular diet can suffer neurological damage, tremors, anxiety and memory problems. The danger of mercury poisoning is particularly high for fetuses and young children.

The plan, a decade in the making and closely scrutinized by environmental groups, was passed Tuesday by the State Water Resources Control Board and needs approval from the U.S. Environmental Protection Agency. The EPA has declared its support of the plan.

The cleanup timetable is so long -- 70 years -- because there is so much mercury-laden sediment in the bay, said Bruce Wolfe, executive officer of the San Francisco Bay Regional Water Quality Control Board, which signed off on the plan last year.

"Obviously, we can't go through and dredge the whole bay," Wolfe said. "The goal is to protect human health and at the same time protect wildlife."

The mercury in the water works its way up to the fish, and then to the birds where it can affect their reproduction, he said.

"We're going straight to the fish -- the receptor -- and setting the limit in fish tissue," Wolfe said.

There are hundreds of sources of mercury. About 1,200 kilograms per year -- or about 2,645 pounds -- reach the bay. Under the cleanup plan, the pollution needs to be whacked to about 700 kilograms per year, or about 1,540 pounds.

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