Last week, I put up a post explaining that BP will be increasing their dumping of toxic waste into the Great Lakes.

Congress overwhelmingly approved a resolution condemning BP’s dumping — a resolution sponsored by Rahm Emanuel, a powerful Democratic Congressman.

Now, thanks to some fine investigative reporting by the Chicago Tribune, we find out that BP has been dumping mercury as well, and will continue to do so:

Federal records analyzed by the Tribune show BP puts 2 pounds of mercury into the lake every year from its sprawling plant 3 miles southeast of Chicago in Whiting, Ind. That amount is small compared with the mercury that falls into the water from air pollution, but mercury builds up in the environment and is so toxic that even tiny drops can threaten fish and people.

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A little-noticed exemption in BP’s controversial new state water permit gives the oil company until 2012 to meet strict federal limits on mercury discharges.

There’s a whole toxic stew that gets discharged into the lakes; and why not, it’s free.

The refinery is the top industrial source of lead, nickel and ammonia pollution directly released into the lake, according to the EPA’s Toxics Release Inventory. It also is one of only two industrial polluters on the lake that dump acetonitrile, a chemical that metabolizes in the environment to cyanide.

But it turns out that coal-fired plants are by far the worst offenders; in fact, the mercury discharged by BP may even come from the lake water they use, which still doesn’t get them off the hook, because they could still clean it up:

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A recent federal study estimated that 880 pounds of the metal drop into Lake Michigan every year, mostly from the smokestacks of coal-fired power plants along and near the shore.

Mercury discharged directly into the lake by BP’s refinery is a mere fraction of that amount. But a growing chorus of critics, including Mayor Richard Daley, Gov. Rod Blagojevich and members of Congress, argue that BP’s new state permit sets a bad precedent that threatens to reverse more than three decades of slow but steady progress cleaning up the lake.

BP’s profit last year was $22 billion. Surely they can spend the money to clean up their mess. But what about the coal-fired plants? As we’ve been reading at Grist, coal is bad. The Great Lakes are good. So, we’ve got oil refineries and coal plants that are (1) frying the atmosphere, (2) going to cause chaos when oil and even coal start to run out; and back to where the environmental movement started, (3) destroying what’s left of our ecosystems, including fresh water.

I know what’s coming: “Your gasoline/electricity prices are rising because those environmentalists won’t let us expand refineries/coal plants.” This is why it is imperative to continue the good works on solar/wind energy, cogeneration, more efficient cars, and public transportation, so that the counterargument can be the following: Prices are rising because (1) cheap oil is running out, (2) rising prices for metals are making power plant construction more expensive, 3) there are much better alternatives.