By John Myers

Minnesota pollution regulators on Wednesday said mercury falling on Minnesota lakes must be cut at least 93 percent before all fish are safe to eat for everyone -- but they stopped short of proposing regulations to help meet that goal.

Instead, the state will wait to see if proposed federal regulations help cut overall mercury emissions before taking action.

The Minnesota Pollution Control Agency mercury plan released Wednesday says fish won't be safe statewide until mercury levels are cut 93 percent from 1990 levels.

That means the sources of thousands of pounds ofhuman-caused mercury pollution have to be shut off or fixed so they no longer spew mercury into the environment.

"This is the first effort to quantify the problem and lay out what we think needs to be done to solve it. It shows where we need to go," said Marvin Hora, manager of the water-assessment section for the Pollution Control Agency. "Now, as we move forward, we can decide how we want to get there and when. But that will take a lot more time to develop."

Scientists have determined where most of the mercury falling in Minnesota comes from. But solving the problem is especially difficult because much of that mercury comes from hundreds, even thousands, of miles away.

Of the mercury that falls here, about 30 percent comes from natural sources such as volcanoes, the agency estimates.

The other 70 percent comes from human-caused sources, most outside the state's borders. State scientists say that cutting only the 10 percent of human-caused mercury that's produced in Minnesota will do little to solve the environmental and public health problems of contaminated fish.

"We could close down every power plant in Minnesota and every mining operation, and it wouldn't make the fish safe to eat," Hora said. "The goal is to cut all sources, state, regional and global, by 93 percent to help solve the problem."

Hora and industry officials say its more prudent to wait for the U.S. Environmental Protection Agency to act on Bush administration mercury-reduction proposals expected in March or April.

"Minnesota can't solve the problem on its own," Hora said.

But environmental groups say Minnesota is shirking its duty to clean up as an example to other states and even other nations. They cite Minnesota's groundbreaking acid-rain legislation in the 1970s that required power plants to reduce sulfur emissions long before federal laws were enacted.

Wisconsin has taken a different tact, not waiting for federal action. In July, Wisconsin regulators enacted tough mercury-reduction regulations, demanding that electric utilities cut mercury emissions in the state by 40 percent by 2010 and 80 percent by 2015.

"Minnesota really can't expect everyone else to clean up their act until we clean up our own," said Michelle Rosier, Minnesota clean air representative for the Sierra Club. "We give the PCA credit for going at a statewide approach to reducing mercury across the state and not just for (problem) lakes. But there really isn't anything substantial in here that will get any reduction."

Rosier said waiting for federal regulations, expected to require a reduction of about 70 percent by 2018, isn't enough for a state that needs clean water and edible fish for its residents and tourists.

"That's way too long to wait to get mercury out of our fish," she said.

The Pollution Control Agency says that in 1990, Minnesota's share of the mercury that falls here was 11,271 pounds. That needs to be cut to 785 pounds annually before mercury levels in fish will drop to levels considered safe, Hora said.

That "safe" level of mercury is based on Northland lakes, which are more sensitive than other lakes in the state. While about the same amount of mercury falls statewide, fish in northern Minnesota lakes have an average of 50 percent more mercury in their tissue than those in southern lakes do.

Some of that reduction in Minnesota-produced mercury has been reached. Laws prohibit mercury in new products, such as batteries, light bulbs and switches -- and mercury from dental offices has been reduced. The result is that mercury released from Minnesota into the environment has been cut by 68 percent over the past 14 years.

But nearly all of that has been from reducing mercury in products. Emissions from Minnesota taconite plants and coal-burning power plants actually increased from 1990 to 2000.

If the state's goal is to be reached, mercury emissions from those plants must be cut by about 82 percent. Industry officials say that's impossible under current technology, at least for existing plants.

"It's a case where the technology is going to have to catch up. It isn't there yet," said Mike Cashin, corporate environmental engineer for Duluth-based Minnesota Power. "And even if we could fix our (share of mercury) right now, the bigger problem is the large amount of naturally produced mercury that's contributing to the problem."

Cashin noted that 70 percent of the human-caused mercury falling in Minnesota may be from Asia -- much of that from China, where an exploding economy has spurred the need for dozens of new coal-fired power plants.

"More of the mercury that (falls in) Minnesota comes from China than from Minnesota," Cashin said.

Gary Glass of Duluth, a longtime mercury researcher, questioned the theory that only 10 percent of Minnesota's mercury comes from within the state. In a six-year study, paid for by the Minnesota Legislature and EPA, Glass studied mercury levels in precipitation at six sites in the region.

"We found indications that local sources (of mercury) contributed to higher levels of mercury in rainfall," Glass said. "That would indicate that reducing levels locally could have a larger impact."