The EPA began working to reduce it: Read here.

It has been greatly reduced since the 70’s in the US. Europe did even better. Here is the wikipedia.

It’s better than it was, but still a problem. NY and a few other states are suing some of the midwest utilities to try to improve it further.

Nothing has happened to it. It’s still a problem. But there are other more popular environmental boogy men that politicians are currently pushing these days.

It got washed away.

Did it dissolve itself?

Laws were enacted to force heavy polluters, particularly electrical power generation plants burning coal or oil, to put scrubbers in their stacks to remove most of the pollution and fly-ash going up the stack. It’s a pretty decent success story, but one that too many Americans have forgotten The new right wants to get rid of the EPA and go back to pollution as usual. They seem to have forgotten that large swaths of forests and grasslands were dying off in the 70s, and that we actually had rivers catching on fire.

Acid rain does dissolve limestone, and as the acidic runoff gets into the waterwys, lakes and seas, it damages marine life as well. Acids escaping from volcanoes can definitely eat up limestone if there is sufficient dampness in the environment, but this is a naturla process that the Earth easily absorbs and compensates for. Human activity is a much larger concern.

Thanks for the input, insight, and links everybody. @ETpro it’s something I like to bring up every once in a while but an article about a sinkhole in China got me started up on this topic. I thought it would be an odd theoretical break-point in industrial activity; where production could reach a point in which the cost of environmental protection is precipitated (npi!) by the cost of collateral destruction from industrial activity. That is to say, acid rain will have to be curbed by the industrial complex because the industrial complex would see it as being in their best interest.