The Indiana Department of Environmental Management (IDEM) has found a way to reduce the number of Indiana water bodies impaired by mercury-laden fish. Unfortunately, it has nothing to do with removing the mercury.
Instead of addressing the problem of mercury from coal-fired power plant emissions, IDEM has grabbed an opportunity offered by the U.S. Environmental Protection Agency (E.P.A.) to change the way it determines what rivers and lakes have such high levels of mercury that the department would have to find a way to clean them up.
Up to now IDEM has listed any water where it found a single fish with mercury levels that exceed the E.P.A. standard. However, the agency allows states to average the amount of mercury contamination in all the fish taken from a sampling site, based on a formula of what types of fish most people catch and eat. Since mercury tends to accumulate in fish at the top of the food chain, like walleye and trout, adding pan fish like bluegills in the calculation lowers the average.
As a result, instead of the 348 mercury-impaired waters currently on the Indiana list, IDEM will inform the E.P.A. that there are only 104. We still have as much mercury and mercury-tainted fish in our waters, but now we have fewer that IDEM needs to worry about.
By itself, the new method is valid, since most people do eat a variety of fish. Indeed, the fish consumption advisories that the state Department of Health issues for many of the waters in our state inform people to eat more of the species lower on the food chain rather than those that are likely to have higher mercury levels. These advisories remain in effect.
Mercury is especially dangerous for young children and women who may become pregnant because it can harm the development of the nervous system, so they should be more cautious about eating fish than the general population. IDEM’s approach doesn’t take that into account.
The E.P.A. wants states to adopt the new fish-tissue mercury concentration into their water quality standards. IDEM isn’t proposing to do that. If it did, it would have to consider putting mercury limits into water discharge permits, which might cause a problem for power plants and coal mines.
The agency would also like to see more states working to clean up waters that have lots of mercury in them. IDEM says that it plans to begin that work, but don’t hold your breath. If it wanted to reduce mercury, it could have begun long ago. We know that power plant emissions are the main source of mercury in our waters. Most of the water bodies that have so many mercury-contaminated fish that they remain on the impaired waters list are in the southern part of the state, downwind from the concentration of power plants in southwestern Indiana.
We don’t need individual clean-up plans for all of these waters. We need a state policy to reduce power-plant emissions. That’s not something we’re likely to see from IDEM. It has resisted the E.P.A.’s request to add other metal-impaired waters to our list because doing so might lead to stricter permits for coal mines.
IDEM is more interested in protecting the coal industry than in protecting people’s health. Its new mercury-impairment policy is further evidence of that.