Pall Corp acquired Gelman Sciences Inc. in 1997.
Here are the company-supplied plume maps for 1998 and 2009 as positioned on Google Earth:
The amount of 1,4-dioxane left to spread as of 2009 is even more dramatic in 3D:
According to the 11/15/2010 Notice of Tentative Agreement on Proposed Modifications to Remedial Obiectives for Gelman Site,
Pall is now proposing to let most of this dioxane go unremediated:..
... including all of the dioxane in this 2800 ppb Well Prohibition Zone box:
... and now, all of the dioxane in or heading to the expanded Evergreen area Prohibition Zone
(some of which may be heading to Barton Pond) that previously was to be cleaned up to 3 or 85 ppb:
There's a lot more dioxane at the core than the 3D maps based on the Pall/Gelman iso-concentration maps depict.
This image adds the actual dixoane ppb readings as bars at each sampling location: