I was reading a while back that here in North America fire departments are not keen on using foam on fires like this as they once did due to environmental concerns.
This is due to reports by different Natural Resource departments of large fish kills down stream of storm sewer outfalls when the foam was washed down during the post fire cleanup.
Apparently the resulting soap film prevents oxygen from entering the water for the fish to breathe.
Does anybody know if the newer plants that use foam suppression systems have some sort of containment system to filter out the soap before the runoff goes offsite.
Just after posting this I came back to add this link from the BBC dated July 6/07 advising of the hazards to the public of fire foam floating down the Thames River
http://news.bbc.co.uk/2/hi/uk_news/england/oxfordshire/6278010.stm
