
Inside a toxic hellhole - timr
http://www.sfgate.com/cgi-bin/article.cgi?f=/c/a/2010/08/29/MNB11F0DKL.DTL&type=green
======
hga
Strange: except for exposing the pyrite to the environment, this is an
entirely natural process....

See
[http://en.wikipedia.org/wiki/Pyrite#Weathering_and_release_o...](http://en.wikipedia.org/wiki/Pyrite#Weathering_and_release_of_sulfate)
and further links from that for more details.

