This link was on the website which I listed in my first post.
Also, there's a good article on page 5 of the pdf located on the following website which I created for the anti-beltway group (CINQ) when it was fighting possible compromise by the City of Golden: http://www.homeingolden.com. Page down to page 5 after the PDF opens on your screen.
Full disclosure: I'm on the board of that anti-beltway group and remain a vigilant and outspoken opponent (unlike my fellow Realtors) of the toll road and beltway proposals.
I used to work at a nuclear power plant, so I wouldn't take this subject lightly, and I know that it's not common to disclose that a neighborhood is built on a superfund site, but I haven't read anything that siad Five Parks was built on one.
If you have more info, I'd be very intersted in seeing it, because I believe people should know the whole truth, even though most would buy a home in a 'cool' neighborhood anyway.