With the membership at more than 2,500 members, group founder Jason McCarty has promoted members to administrators—so they can help him follow and moderate the discussion about whether Fridley’s could be due to environmental causes.
Group members continue to share anecdotes about friends, family and neighbors who contracted cancer after living in the city.
Here’s a rundown on recent developments and topics of discussion within the group:
- A group member posted a link to a 1991 report on the Prairie du Chien Aquifer in Fridley. “TCE contamination was found in this aquifer,” the member wrote. “Not a light read, but could have very useful information, especially when considering vapor intrusion.” (Editor's note: I've uploaded the full report but it's not very legible, so I'm working on posting it in portions that you can read better.)
- Group founder Jason McCarty uploaded to YouTube a video from an October 23, 1989, Fridley City Council meeting discussing the chemical TCE and posted a link to the group’s discussion board. Jim Bauer, a citizen featured in the video, shared it with McCarty. (See the video above.)
- Daniel Steltz, an environmental chemist, has been answering group members’ questions about TCE and other contaminants. Here are his latest comments:
First, having considered various stages of the municipal water delivery system as well as any in home water holding tanks in conjunction with the concentrations of TCE being discussed and the documented contamination sites, I would say that it is reasonable to conclude that any TCE contamination that was present at any given time would have been uniformly distributed in the water supply. Thus any intake would have occurred at the documented level of contamination through drinking waters or through water vapors during a shower, but not in larger concentrated "doses" due to settling in reservoirs.
To further explain volatility, this simply means that a specific substance is difficult to contain in liquid form and that it "spits out" molecules into the gaseous phase at a rapid rate. Basically it means that though TCE condenses into a liquid, it prefers to be a gas. This does not have any factor in the molecules actual reactivity with other substances. It is safe to say that in the conditions present, TCE would have remained as TCE and would not have reacted with any other molecules or atoms. In order to rust a metal, a molecule has to be what is called an oxidizing agent. It has to be able to strip electrons away from the metal, and is commonly done by bonding to an oxygen atom.
With regards to your inquiry about 1,1,1-Tricholoroethane, it is actually a very different molecule than TCE. It is manufactured from the 1,1-Dichloroethylene which is perhaps a bit more similar structurally to Trichloroethylene, but still very different physically. This difference is because of a plane of symmetry that can be drawn down the center of the molecule in addition to the difference in what is called electron density between the Hydrogen and Chlorine, Chlorine having the higher of the two. This combination of symmetry and electron densities creates what is called a polar molecule, in which most of the electrons can be found residing in one end of the molecule over the other. With TCE, the electron densities are relatively uniform throughout the molecule.