Just a couple of my thoughts from a chemistry point of view...
The mint produced both formulations of pennies in 1982 so I don't know where they get this "don't use pre 1982 pennies" from. You would have to have access to a microbalance sensitive to at least 0.1 gram to tell the difference between the densities of the two types.
Berkeley Pit: Those birds did indeed die from ingesting strong acidic water (sulfuric acid, like battery acid). When they closed the mine in the 1980s I became involved in research to remediate the toxic metals in the water and this involved characterization of the water samples. There was indeed a lot of copper in the water, many grams per liter as I recall. But the acid would have killed the birds almost instantly.
City water: Many cities alkalize their water to prevent corrosion in pipes, their special interest being to prevent lead poisoning in children living in older homes. But it should reduce copper corrosion also. If you have well water you can always have it analyzed, it will cost you though.
My mantra is to keep metal objects out of water features. It is so much easier to
not do something than to do something and
then worry about it.
My 2 cents worth (one each 1982
)
