rising copper levels in ash from incinerator Palo Alto Issues, posted by Walter_E_Wallis, a resident of the Midtown neighborhood, on Jun 14, 2007 at 8:18 pm
"Other people, including Palo Altan Jeff Hoel, postulate a link between San Francisco Public Utilities Commission's addition of chloramine to its water supply in 2004"
I gotta agree with Jeff. Almost any change in water makeup can disturb the corrosion pattern.